1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2011, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Checks; use Checks;
28 with Debug; use Debug;
29 with Elists; use Elists;
30 with Einfo; use Einfo;
31 with Errout; use Errout;
32 with Eval_Fat; use Eval_Fat;
33 with Exp_Ch3; use Exp_Ch3;
34 with Exp_Ch9; use Exp_Ch9;
35 with Exp_Disp; use Exp_Disp;
36 with Exp_Dist; use Exp_Dist;
37 with Exp_Tss; use Exp_Tss;
38 with Exp_Util; use Exp_Util;
39 with Fname; use Fname;
40 with Freeze; use Freeze;
41 with Itypes; use Itypes;
42 with Layout; use Layout;
44 with Lib.Xref; use Lib.Xref;
45 with Namet; use Namet;
46 with Nmake; use Nmake;
48 with Restrict; use Restrict;
49 with Rident; use Rident;
50 with Rtsfind; use Rtsfind;
52 with Sem_Aux; use Sem_Aux;
53 with Sem_Case; use Sem_Case;
54 with Sem_Cat; use Sem_Cat;
55 with Sem_Ch6; use Sem_Ch6;
56 with Sem_Ch7; use Sem_Ch7;
57 with Sem_Ch8; use Sem_Ch8;
58 with Sem_Ch13; use Sem_Ch13;
59 with Sem_Dim; use Sem_Dim;
60 with Sem_Disp; use Sem_Disp;
61 with Sem_Dist; use Sem_Dist;
62 with Sem_Elim; use Sem_Elim;
63 with Sem_Eval; use Sem_Eval;
64 with Sem_Mech; use Sem_Mech;
65 with Sem_Prag; use Sem_Prag;
66 with Sem_Res; use Sem_Res;
67 with Sem_Smem; use Sem_Smem;
68 with Sem_Type; use Sem_Type;
69 with Sem_Util; use Sem_Util;
70 with Sem_Warn; use Sem_Warn;
71 with Stand; use Stand;
72 with Sinfo; use Sinfo;
73 with Sinput; use Sinput;
74 with Snames; use Snames;
75 with Targparm; use Targparm;
76 with Tbuild; use Tbuild;
77 with Ttypes; use Ttypes;
78 with Uintp; use Uintp;
79 with Urealp; use Urealp;
81 package body Sem_Ch3 is
83 -----------------------
84 -- Local Subprograms --
85 -----------------------
87 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
88 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
89 -- abstract interface types implemented by a record type or a derived
92 procedure Build_Derived_Type
94 Parent_Type : Entity_Id;
95 Derived_Type : Entity_Id;
96 Is_Completion : Boolean;
97 Derive_Subps : Boolean := True);
98 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
99 -- the N_Full_Type_Declaration node containing the derived type definition.
100 -- Parent_Type is the entity for the parent type in the derived type
101 -- definition and Derived_Type the actual derived type. Is_Completion must
102 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
103 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
104 -- completion of a private type declaration. If Is_Completion is set to
105 -- True, N is the completion of a private type declaration and Derived_Type
106 -- is different from the defining identifier inside N (i.e. Derived_Type /=
107 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
108 -- subprograms should be derived. The only case where this parameter is
109 -- False is when Build_Derived_Type is recursively called to process an
110 -- implicit derived full type for a type derived from a private type (in
111 -- that case the subprograms must only be derived for the private view of
114 -- ??? These flags need a bit of re-examination and re-documentation:
115 -- ??? are they both necessary (both seem related to the recursion)?
117 procedure Build_Derived_Access_Type
119 Parent_Type : Entity_Id;
120 Derived_Type : Entity_Id);
121 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
122 -- create an implicit base if the parent type is constrained or if the
123 -- subtype indication has a constraint.
125 procedure Build_Derived_Array_Type
127 Parent_Type : Entity_Id;
128 Derived_Type : Entity_Id);
129 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
130 -- create an implicit base if the parent type is constrained or if the
131 -- subtype indication has a constraint.
133 procedure Build_Derived_Concurrent_Type
135 Parent_Type : Entity_Id;
136 Derived_Type : Entity_Id);
137 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
138 -- protected type, inherit entries and protected subprograms, check
139 -- legality of discriminant constraints if any.
141 procedure Build_Derived_Enumeration_Type
143 Parent_Type : Entity_Id;
144 Derived_Type : Entity_Id);
145 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
146 -- type, we must create a new list of literals. Types derived from
147 -- Character and [Wide_]Wide_Character are special-cased.
149 procedure Build_Derived_Numeric_Type
151 Parent_Type : Entity_Id;
152 Derived_Type : Entity_Id);
153 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
154 -- an anonymous base type, and propagate constraint to subtype if needed.
156 procedure Build_Derived_Private_Type
158 Parent_Type : Entity_Id;
159 Derived_Type : Entity_Id;
160 Is_Completion : Boolean;
161 Derive_Subps : Boolean := True);
162 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
163 -- because the parent may or may not have a completion, and the derivation
164 -- may itself be a completion.
166 procedure Build_Derived_Record_Type
168 Parent_Type : Entity_Id;
169 Derived_Type : Entity_Id;
170 Derive_Subps : Boolean := True);
171 -- Subsidiary procedure for Build_Derived_Type and
172 -- Analyze_Private_Extension_Declaration used for tagged and untagged
173 -- record types. All parameters are as in Build_Derived_Type except that
174 -- N, in addition to being an N_Full_Type_Declaration node, can also be an
175 -- N_Private_Extension_Declaration node. See the definition of this routine
176 -- for much more info. Derive_Subps indicates whether subprograms should
177 -- be derived from the parent type. The only case where Derive_Subps is
178 -- False is for an implicit derived full type for a type derived from a
179 -- private type (see Build_Derived_Type).
181 procedure Build_Discriminal (Discrim : Entity_Id);
182 -- Create the discriminal corresponding to discriminant Discrim, that is
183 -- the parameter corresponding to Discrim to be used in initialization
184 -- procedures for the type where Discrim is a discriminant. Discriminals
185 -- are not used during semantic analysis, and are not fully defined
186 -- entities until expansion. Thus they are not given a scope until
187 -- initialization procedures are built.
189 function Build_Discriminant_Constraints
192 Derived_Def : Boolean := False) return Elist_Id;
193 -- Validate discriminant constraints and return the list of the constraints
194 -- in order of discriminant declarations, where T is the discriminated
195 -- unconstrained type. Def is the N_Subtype_Indication node where the
196 -- discriminants constraints for T are specified. Derived_Def is True
197 -- when building the discriminant constraints in a derived type definition
198 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
199 -- type and Def is the constraint "(xxx)" on T and this routine sets the
200 -- Corresponding_Discriminant field of the discriminants in the derived
201 -- type D to point to the corresponding discriminants in the parent type T.
203 procedure Build_Discriminated_Subtype
207 Related_Nod : Node_Id;
208 For_Access : Boolean := False);
209 -- Subsidiary procedure to Constrain_Discriminated_Type and to
210 -- Process_Incomplete_Dependents. Given
212 -- T (a possibly discriminated base type)
213 -- Def_Id (a very partially built subtype for T),
215 -- the call completes Def_Id to be the appropriate E_*_Subtype.
217 -- The Elist is the list of discriminant constraints if any (it is set
218 -- to No_Elist if T is not a discriminated type, and to an empty list if
219 -- T has discriminants but there are no discriminant constraints). The
220 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
221 -- The For_Access says whether or not this subtype is really constraining
222 -- an access type. That is its sole purpose is the designated type of an
223 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
224 -- is built to avoid freezing T when the access subtype is frozen.
226 function Build_Scalar_Bound
229 Der_T : Entity_Id) return Node_Id;
230 -- The bounds of a derived scalar type are conversions of the bounds of
231 -- the parent type. Optimize the representation if the bounds are literals.
232 -- Needs a more complete spec--what are the parameters exactly, and what
233 -- exactly is the returned value, and how is Bound affected???
235 procedure Build_Underlying_Full_View
239 -- If the completion of a private type is itself derived from a private
240 -- type, or if the full view of a private subtype is itself private, the
241 -- back-end has no way to compute the actual size of this type. We build
242 -- an internal subtype declaration of the proper parent type to convey
243 -- this information. This extra mechanism is needed because a full
244 -- view cannot itself have a full view (it would get clobbered during
247 procedure Check_Access_Discriminant_Requires_Limited
250 -- Check the restriction that the type to which an access discriminant
251 -- belongs must be a concurrent type or a descendant of a type with
252 -- the reserved word 'limited' in its declaration.
254 procedure Check_Anonymous_Access_Components
258 Comp_List : Node_Id);
259 -- Ada 2005 AI-382: an access component in a record definition can refer to
260 -- the enclosing record, in which case it denotes the type itself, and not
261 -- the current instance of the type. We create an anonymous access type for
262 -- the component, and flag it as an access to a component, so accessibility
263 -- checks are properly performed on it. The declaration of the access type
264 -- is placed ahead of that of the record to prevent order-of-elaboration
265 -- circularity issues in Gigi. We create an incomplete type for the record
266 -- declaration, which is the designated type of the anonymous access.
268 procedure Check_Delta_Expression (E : Node_Id);
269 -- Check that the expression represented by E is suitable for use as a
270 -- delta expression, i.e. it is of real type and is static.
272 procedure Check_Digits_Expression (E : Node_Id);
273 -- Check that the expression represented by E is suitable for use as a
274 -- digits expression, i.e. it is of integer type, positive and static.
276 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
277 -- Validate the initialization of an object declaration. T is the required
278 -- type, and Exp is the initialization expression.
280 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
281 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
283 procedure Check_Or_Process_Discriminants
286 Prev : Entity_Id := Empty);
287 -- If N is the full declaration of the completion T of an incomplete or
288 -- private type, check its discriminants (which are already known to be
289 -- conformant with those of the partial view, see Find_Type_Name),
290 -- otherwise process them. Prev is the entity of the partial declaration,
293 procedure Check_Real_Bound (Bound : Node_Id);
294 -- Check given bound for being of real type and static. If not, post an
295 -- appropriate message, and rewrite the bound with the real literal zero.
297 procedure Constant_Redeclaration
301 -- Various checks on legality of full declaration of deferred constant.
302 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
303 -- node. The caller has not yet set any attributes of this entity.
305 function Contain_Interface
307 Ifaces : Elist_Id) return Boolean;
308 -- Ada 2005: Determine whether Iface is present in the list Ifaces
310 procedure Convert_Scalar_Bounds
312 Parent_Type : Entity_Id;
313 Derived_Type : Entity_Id;
315 -- For derived scalar types, convert the bounds in the type definition to
316 -- the derived type, and complete their analysis. Given a constraint of the
317 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
318 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
319 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
320 -- subtype are conversions of those bounds to the derived_type, so that
321 -- their typing is consistent.
323 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
324 -- Copies attributes from array base type T2 to array base type T1. Copies
325 -- only attributes that apply to base types, but not subtypes.
327 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
328 -- Copies attributes from array subtype T2 to array subtype T1. Copies
329 -- attributes that apply to both subtypes and base types.
331 procedure Create_Constrained_Components
335 Constraints : Elist_Id);
336 -- Build the list of entities for a constrained discriminated record
337 -- subtype. If a component depends on a discriminant, replace its subtype
338 -- using the discriminant values in the discriminant constraint. Subt
339 -- is the defining identifier for the subtype whose list of constrained
340 -- entities we will create. Decl_Node is the type declaration node where
341 -- we will attach all the itypes created. Typ is the base discriminated
342 -- type for the subtype Subt. Constraints is the list of discriminant
343 -- constraints for Typ.
345 function Constrain_Component_Type
347 Constrained_Typ : Entity_Id;
348 Related_Node : Node_Id;
350 Constraints : Elist_Id) return Entity_Id;
351 -- Given a discriminated base type Typ, a list of discriminant constraint
352 -- Constraints for Typ and a component of Typ, with type Compon_Type,
353 -- create and return the type corresponding to Compon_type where all
354 -- discriminant references are replaced with the corresponding constraint.
355 -- If no discriminant references occur in Compon_Typ then return it as is.
356 -- Constrained_Typ is the final constrained subtype to which the
357 -- constrained Compon_Type belongs. Related_Node is the node where we will
358 -- attach all the itypes created.
360 -- Above description is confused, what is Compon_Type???
362 procedure Constrain_Access
363 (Def_Id : in out Entity_Id;
365 Related_Nod : Node_Id);
366 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
367 -- an anonymous type created for a subtype indication. In that case it is
368 -- created in the procedure and attached to Related_Nod.
370 procedure Constrain_Array
371 (Def_Id : in out Entity_Id;
373 Related_Nod : Node_Id;
374 Related_Id : Entity_Id;
376 -- Apply a list of index constraints to an unconstrained array type. The
377 -- first parameter is the entity for the resulting subtype. A value of
378 -- Empty for Def_Id indicates that an implicit type must be created, but
379 -- creation is delayed (and must be done by this procedure) because other
380 -- subsidiary implicit types must be created first (which is why Def_Id
381 -- is an in/out parameter). The second parameter is a subtype indication
382 -- node for the constrained array to be created (e.g. something of the
383 -- form string (1 .. 10)). Related_Nod gives the place where this type
384 -- has to be inserted in the tree. The Related_Id and Suffix parameters
385 -- are used to build the associated Implicit type name.
387 procedure Constrain_Concurrent
388 (Def_Id : in out Entity_Id;
390 Related_Nod : Node_Id;
391 Related_Id : Entity_Id;
393 -- Apply list of discriminant constraints to an unconstrained concurrent
396 -- SI is the N_Subtype_Indication node containing the constraint and
397 -- the unconstrained type to constrain.
399 -- Def_Id is the entity for the resulting constrained subtype. A value
400 -- of Empty for Def_Id indicates that an implicit type must be created,
401 -- but creation is delayed (and must be done by this procedure) because
402 -- other subsidiary implicit types must be created first (which is why
403 -- Def_Id is an in/out parameter).
405 -- Related_Nod gives the place where this type has to be inserted
408 -- The last two arguments are used to create its external name if needed.
410 function Constrain_Corresponding_Record
411 (Prot_Subt : Entity_Id;
412 Corr_Rec : Entity_Id;
413 Related_Nod : Node_Id;
414 Related_Id : Entity_Id) return Entity_Id;
415 -- When constraining a protected type or task type with discriminants,
416 -- constrain the corresponding record with the same discriminant values.
418 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
419 -- Constrain a decimal fixed point type with a digits constraint and/or a
420 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
422 procedure Constrain_Discriminated_Type
425 Related_Nod : Node_Id;
426 For_Access : Boolean := False);
427 -- Process discriminant constraints of composite type. Verify that values
428 -- have been provided for all discriminants, that the original type is
429 -- unconstrained, and that the types of the supplied expressions match
430 -- the discriminant types. The first three parameters are like in routine
431 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
434 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
435 -- Constrain an enumeration type with a range constraint. This is identical
436 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
438 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
439 -- Constrain a floating point type with either a digits constraint
440 -- and/or a range constraint, building a E_Floating_Point_Subtype.
442 procedure Constrain_Index
445 Related_Nod : Node_Id;
446 Related_Id : Entity_Id;
449 -- Process an index constraint S in a constrained array declaration. The
450 -- constraint can be a subtype name, or a range with or without an explicit
451 -- subtype mark. The index is the corresponding index of the unconstrained
452 -- array. The Related_Id and Suffix parameters are used to build the
453 -- associated Implicit type name.
455 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
456 -- Build subtype of a signed or modular integer type
458 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
459 -- Constrain an ordinary fixed point type with a range constraint, and
460 -- build an E_Ordinary_Fixed_Point_Subtype entity.
462 procedure Copy_And_Swap (Priv, Full : Entity_Id);
463 -- Copy the Priv entity into the entity of its full declaration then swap
464 -- the two entities in such a manner that the former private type is now
465 -- seen as a full type.
467 procedure Decimal_Fixed_Point_Type_Declaration
470 -- Create a new decimal fixed point type, and apply the constraint to
471 -- obtain a subtype of this new type.
473 procedure Complete_Private_Subtype
476 Full_Base : Entity_Id;
477 Related_Nod : Node_Id);
478 -- Complete the implicit full view of a private subtype by setting the
479 -- appropriate semantic fields. If the full view of the parent is a record
480 -- type, build constrained components of subtype.
482 procedure Derive_Progenitor_Subprograms
483 (Parent_Type : Entity_Id;
484 Tagged_Type : Entity_Id);
485 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
486 -- operations of progenitors of Tagged_Type, and replace the subsidiary
487 -- subtypes with Tagged_Type, to build the specs of the inherited interface
488 -- primitives. The derived primitives are aliased to those of the
489 -- interface. This routine takes care also of transferring to the full view
490 -- subprograms associated with the partial view of Tagged_Type that cover
491 -- interface primitives.
493 procedure Derived_Standard_Character
495 Parent_Type : Entity_Id;
496 Derived_Type : Entity_Id);
497 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
498 -- derivations from types Standard.Character and Standard.Wide_Character.
500 procedure Derived_Type_Declaration
503 Is_Completion : Boolean);
504 -- Process a derived type declaration. Build_Derived_Type is invoked
505 -- to process the actual derived type definition. Parameters N and
506 -- Is_Completion have the same meaning as in Build_Derived_Type.
507 -- T is the N_Defining_Identifier for the entity defined in the
508 -- N_Full_Type_Declaration node N, that is T is the derived type.
510 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
511 -- Insert each literal in symbol table, as an overloadable identifier. Each
512 -- enumeration type is mapped into a sequence of integers, and each literal
513 -- is defined as a constant with integer value. If any of the literals are
514 -- character literals, the type is a character type, which means that
515 -- strings are legal aggregates for arrays of components of the type.
517 function Expand_To_Stored_Constraint
519 Constraint : Elist_Id) return Elist_Id;
520 -- Given a constraint (i.e. a list of expressions) on the discriminants of
521 -- Typ, expand it into a constraint on the stored discriminants and return
522 -- the new list of expressions constraining the stored discriminants.
524 function Find_Type_Of_Object
526 Related_Nod : Node_Id) return Entity_Id;
527 -- Get type entity for object referenced by Obj_Def, attaching the
528 -- implicit types generated to Related_Nod
530 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
531 -- Create a new float and apply the constraint to obtain subtype of it
533 function Has_Range_Constraint (N : Node_Id) return Boolean;
534 -- Given an N_Subtype_Indication node N, return True if a range constraint
535 -- is present, either directly, or as part of a digits or delta constraint.
536 -- In addition, a digits constraint in the decimal case returns True, since
537 -- it establishes a default range if no explicit range is present.
539 function Inherit_Components
541 Parent_Base : Entity_Id;
542 Derived_Base : Entity_Id;
544 Inherit_Discr : Boolean;
545 Discs : Elist_Id) return Elist_Id;
546 -- Called from Build_Derived_Record_Type to inherit the components of
547 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
548 -- For more information on derived types and component inheritance please
549 -- consult the comment above the body of Build_Derived_Record_Type.
551 -- N is the original derived type declaration
553 -- Is_Tagged is set if we are dealing with tagged types
555 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
556 -- Parent_Base, otherwise no discriminants are inherited.
558 -- Discs gives the list of constraints that apply to Parent_Base in the
559 -- derived type declaration. If Discs is set to No_Elist, then we have
560 -- the following situation:
562 -- type Parent (D1..Dn : ..) is [tagged] record ...;
563 -- type Derived is new Parent [with ...];
565 -- which gets treated as
567 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
569 -- For untagged types the returned value is an association list. The list
570 -- starts from the association (Parent_Base => Derived_Base), and then it
571 -- contains a sequence of the associations of the form
573 -- (Old_Component => New_Component),
575 -- where Old_Component is the Entity_Id of a component in Parent_Base and
576 -- New_Component is the Entity_Id of the corresponding component in
577 -- Derived_Base. For untagged records, this association list is needed when
578 -- copying the record declaration for the derived base. In the tagged case
579 -- the value returned is irrelevant.
581 function Is_Valid_Constraint_Kind
583 Constraint_Kind : Node_Kind) return Boolean;
584 -- Returns True if it is legal to apply the given kind of constraint to the
585 -- given kind of type (index constraint to an array type, for example).
587 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
588 -- Create new modular type. Verify that modulus is in bounds
590 procedure New_Concatenation_Op (Typ : Entity_Id);
591 -- Create an abbreviated declaration for an operator in order to
592 -- materialize concatenation on array types.
594 procedure Ordinary_Fixed_Point_Type_Declaration
597 -- Create a new ordinary fixed point type, and apply the constraint to
598 -- obtain subtype of it.
600 procedure Prepare_Private_Subtype_Completion
602 Related_Nod : Node_Id);
603 -- Id is a subtype of some private type. Creates the full declaration
604 -- associated with Id whenever possible, i.e. when the full declaration
605 -- of the base type is already known. Records each subtype into
606 -- Private_Dependents of the base type.
608 procedure Process_Incomplete_Dependents
612 -- Process all entities that depend on an incomplete type. There include
613 -- subtypes, subprogram types that mention the incomplete type in their
614 -- profiles, and subprogram with access parameters that designate the
617 -- Inc_T is the defining identifier of an incomplete type declaration, its
618 -- Ekind is E_Incomplete_Type.
620 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
622 -- Full_T is N's defining identifier.
624 -- Subtypes of incomplete types with discriminants are completed when the
625 -- parent type is. This is simpler than private subtypes, because they can
626 -- only appear in the same scope, and there is no need to exchange views.
627 -- Similarly, access_to_subprogram types may have a parameter or a return
628 -- type that is an incomplete type, and that must be replaced with the
631 -- If the full type is tagged, subprogram with access parameters that
632 -- designated the incomplete may be primitive operations of the full type,
633 -- and have to be processed accordingly.
635 procedure Process_Real_Range_Specification (Def : Node_Id);
636 -- Given the type definition for a real type, this procedure processes and
637 -- checks the real range specification of this type definition if one is
638 -- present. If errors are found, error messages are posted, and the
639 -- Real_Range_Specification of Def is reset to Empty.
641 procedure Record_Type_Declaration
645 -- Process a record type declaration (for both untagged and tagged
646 -- records). Parameters T and N are exactly like in procedure
647 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
648 -- for this routine. If this is the completion of an incomplete type
649 -- declaration, Prev is the entity of the incomplete declaration, used for
650 -- cross-referencing. Otherwise Prev = T.
652 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
653 -- This routine is used to process the actual record type definition (both
654 -- for untagged and tagged records). Def is a record type definition node.
655 -- This procedure analyzes the components in this record type definition.
656 -- Prev_T is the entity for the enclosing record type. It is provided so
657 -- that its Has_Task flag can be set if any of the component have Has_Task
658 -- set. If the declaration is the completion of an incomplete type
659 -- declaration, Prev_T is the original incomplete type, whose full view is
662 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
663 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
664 -- build a copy of the declaration tree of the parent, and we create
665 -- independently the list of components for the derived type. Semantic
666 -- information uses the component entities, but record representation
667 -- clauses are validated on the declaration tree. This procedure replaces
668 -- discriminants and components in the declaration with those that have
669 -- been created by Inherit_Components.
671 procedure Set_Fixed_Range
676 -- Build a range node with the given bounds and set it as the Scalar_Range
677 -- of the given fixed-point type entity. Loc is the source location used
678 -- for the constructed range. See body for further details.
680 procedure Set_Scalar_Range_For_Subtype
684 -- This routine is used to set the scalar range field for a subtype given
685 -- Def_Id, the entity for the subtype, and R, the range expression for the
686 -- scalar range. Subt provides the parent subtype to be used to analyze,
687 -- resolve, and check the given range.
689 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
690 -- Create a new signed integer entity, and apply the constraint to obtain
691 -- the required first named subtype of this type.
693 procedure Set_Stored_Constraint_From_Discriminant_Constraint
695 -- E is some record type. This routine computes E's Stored_Constraint
696 -- from its Discriminant_Constraint.
698 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
699 -- Check that an entity in a list of progenitors is an interface,
700 -- emit error otherwise.
702 -----------------------
703 -- Access_Definition --
704 -----------------------
706 function Access_Definition
707 (Related_Nod : Node_Id;
708 N : Node_Id) return Entity_Id
710 Anon_Type : Entity_Id;
711 Anon_Scope : Entity_Id;
712 Desig_Type : Entity_Id;
713 Enclosing_Prot_Type : Entity_Id := Empty;
716 Check_SPARK_Restriction ("access type is not allowed", N);
718 if Is_Entry (Current_Scope)
719 and then Is_Task_Type (Etype (Scope (Current_Scope)))
721 Error_Msg_N ("task entries cannot have access parameters", N);
725 -- Ada 2005: for an object declaration the corresponding anonymous
726 -- type is declared in the current scope.
728 -- If the access definition is the return type of another access to
729 -- function, scope is the current one, because it is the one of the
730 -- current type declaration, except for the pathological case below.
732 if Nkind_In (Related_Nod, N_Object_Declaration,
733 N_Access_Function_Definition)
735 Anon_Scope := Current_Scope;
737 -- A pathological case: function returning access functions that
738 -- return access functions, etc. Each anonymous access type created
739 -- is in the enclosing scope of the outermost function.
746 while Nkind_In (Par, N_Access_Function_Definition,
752 if Nkind (Par) = N_Function_Specification then
753 Anon_Scope := Scope (Defining_Entity (Par));
757 -- For the anonymous function result case, retrieve the scope of the
758 -- function specification's associated entity rather than using the
759 -- current scope. The current scope will be the function itself if the
760 -- formal part is currently being analyzed, but will be the parent scope
761 -- in the case of a parameterless function, and we always want to use
762 -- the function's parent scope. Finally, if the function is a child
763 -- unit, we must traverse the tree to retrieve the proper entity.
765 elsif Nkind (Related_Nod) = N_Function_Specification
766 and then Nkind (Parent (N)) /= N_Parameter_Specification
768 -- If the current scope is a protected type, the anonymous access
769 -- is associated with one of the protected operations, and must
770 -- be available in the scope that encloses the protected declaration.
771 -- Otherwise the type is in the scope enclosing the subprogram.
773 -- If the function has formals, The return type of a subprogram
774 -- declaration is analyzed in the scope of the subprogram (see
775 -- Process_Formals) and thus the protected type, if present, is
776 -- the scope of the current function scope.
778 if Ekind (Current_Scope) = E_Protected_Type then
779 Enclosing_Prot_Type := Current_Scope;
781 elsif Ekind (Current_Scope) = E_Function
782 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
784 Enclosing_Prot_Type := Scope (Current_Scope);
787 if Present (Enclosing_Prot_Type) then
788 Anon_Scope := Scope (Enclosing_Prot_Type);
791 Anon_Scope := Scope (Defining_Entity (Related_Nod));
794 -- For an access type definition, if the current scope is a child
795 -- unit it is the scope of the type.
797 elsif Is_Compilation_Unit (Current_Scope) then
798 Anon_Scope := Current_Scope;
800 -- For access formals, access components, and access discriminants, the
801 -- scope is that of the enclosing declaration,
804 Anon_Scope := Scope (Current_Scope);
809 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
812 and then Ada_Version >= Ada_2005
814 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
817 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
818 -- the corresponding semantic routine
820 if Present (Access_To_Subprogram_Definition (N)) then
822 -- Compiler runtime units are compiled in Ada 2005 mode when building
823 -- the runtime library but must also be compilable in Ada 95 mode
824 -- (when bootstrapping the compiler).
826 Check_Compiler_Unit (N);
828 Access_Subprogram_Declaration
829 (T_Name => Anon_Type,
830 T_Def => Access_To_Subprogram_Definition (N));
832 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
834 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
837 (Anon_Type, E_Anonymous_Access_Subprogram_Type);
840 Set_Can_Use_Internal_Rep
841 (Anon_Type, not Always_Compatible_Rep_On_Target);
843 -- If the anonymous access is associated with a protected operation,
844 -- create a reference to it after the enclosing protected definition
845 -- because the itype will be used in the subsequent bodies.
847 if Ekind (Current_Scope) = E_Protected_Type then
848 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
854 Find_Type (Subtype_Mark (N));
855 Desig_Type := Entity (Subtype_Mark (N));
857 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
858 Set_Etype (Anon_Type, Anon_Type);
860 -- Make sure the anonymous access type has size and alignment fields
861 -- set, as required by gigi. This is necessary in the case of the
862 -- Task_Body_Procedure.
864 if not Has_Private_Component (Desig_Type) then
865 Layout_Type (Anon_Type);
868 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
869 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
870 -- the null value is allowed. In Ada 95 the null value is never allowed.
872 if Ada_Version >= Ada_2005 then
873 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
875 Set_Can_Never_Be_Null (Anon_Type, True);
878 -- The anonymous access type is as public as the discriminated type or
879 -- subprogram that defines it. It is imported (for back-end purposes)
880 -- if the designated type is.
882 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
884 -- Ada 2005 (AI-231): Propagate the access-constant attribute
886 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
888 -- The context is either a subprogram declaration, object declaration,
889 -- or an access discriminant, in a private or a full type declaration.
890 -- In the case of a subprogram, if the designated type is incomplete,
891 -- the operation will be a primitive operation of the full type, to be
892 -- updated subsequently. If the type is imported through a limited_with
893 -- clause, the subprogram is not a primitive operation of the type
894 -- (which is declared elsewhere in some other scope).
896 if Ekind (Desig_Type) = E_Incomplete_Type
897 and then not From_With_Type (Desig_Type)
898 and then Is_Overloadable (Current_Scope)
900 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
901 Set_Has_Delayed_Freeze (Current_Scope);
904 -- Ada 2005: if the designated type is an interface that may contain
905 -- tasks, create a Master entity for the declaration. This must be done
906 -- before expansion of the full declaration, because the declaration may
907 -- include an expression that is an allocator, whose expansion needs the
908 -- proper Master for the created tasks.
910 if Nkind (Related_Nod) = N_Object_Declaration
911 and then Expander_Active
913 if Is_Interface (Desig_Type)
914 and then Is_Limited_Record (Desig_Type)
916 Build_Class_Wide_Master (Anon_Type);
918 -- Similarly, if the type is an anonymous access that designates
919 -- tasks, create a master entity for it in the current context.
921 elsif Has_Task (Desig_Type)
922 and then Comes_From_Source (Related_Nod)
924 Build_Master_Entity (Defining_Identifier (Related_Nod));
925 Build_Master_Renaming (Anon_Type);
929 -- For a private component of a protected type, it is imperative that
930 -- the back-end elaborate the type immediately after the protected
931 -- declaration, because this type will be used in the declarations
932 -- created for the component within each protected body, so we must
933 -- create an itype reference for it now.
935 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
936 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
938 -- Similarly, if the access definition is the return result of a
939 -- function, create an itype reference for it because it will be used
940 -- within the function body. For a regular function that is not a
941 -- compilation unit, insert reference after the declaration. For a
942 -- protected operation, insert it after the enclosing protected type
943 -- declaration. In either case, do not create a reference for a type
944 -- obtained through a limited_with clause, because this would introduce
945 -- semantic dependencies.
947 -- Similarly, do not create a reference if the designated type is a
948 -- generic formal, because no use of it will reach the backend.
950 elsif Nkind (Related_Nod) = N_Function_Specification
951 and then not From_With_Type (Desig_Type)
952 and then not Is_Generic_Type (Desig_Type)
954 if Present (Enclosing_Prot_Type) then
955 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
957 elsif Is_List_Member (Parent (Related_Nod))
958 and then Nkind (Parent (N)) /= N_Parameter_Specification
960 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
963 -- Finally, create an itype reference for an object declaration of an
964 -- anonymous access type. This is strictly necessary only for deferred
965 -- constants, but in any case will avoid out-of-scope problems in the
968 elsif Nkind (Related_Nod) = N_Object_Declaration then
969 Build_Itype_Reference (Anon_Type, Related_Nod);
973 end Access_Definition;
975 -----------------------------------
976 -- Access_Subprogram_Declaration --
977 -----------------------------------
979 procedure Access_Subprogram_Declaration
984 procedure Check_For_Premature_Usage (Def : Node_Id);
985 -- Check that type T_Name is not used, directly or recursively, as a
986 -- parameter or a return type in Def. Def is either a subtype, an
987 -- access_definition, or an access_to_subprogram_definition.
989 -------------------------------
990 -- Check_For_Premature_Usage --
991 -------------------------------
993 procedure Check_For_Premature_Usage (Def : Node_Id) is
997 -- Check for a subtype mark
999 if Nkind (Def) in N_Has_Etype then
1000 if Etype (Def) = T_Name then
1002 ("type& cannot be used before end of its declaration", Def);
1005 -- If this is not a subtype, then this is an access_definition
1007 elsif Nkind (Def) = N_Access_Definition then
1008 if Present (Access_To_Subprogram_Definition (Def)) then
1009 Check_For_Premature_Usage
1010 (Access_To_Subprogram_Definition (Def));
1012 Check_For_Premature_Usage (Subtype_Mark (Def));
1015 -- The only cases left are N_Access_Function_Definition and
1016 -- N_Access_Procedure_Definition.
1019 if Present (Parameter_Specifications (Def)) then
1020 Param := First (Parameter_Specifications (Def));
1021 while Present (Param) loop
1022 Check_For_Premature_Usage (Parameter_Type (Param));
1023 Param := Next (Param);
1027 if Nkind (Def) = N_Access_Function_Definition then
1028 Check_For_Premature_Usage (Result_Definition (Def));
1031 end Check_For_Premature_Usage;
1035 Formals : constant List_Id := Parameter_Specifications (T_Def);
1038 Desig_Type : constant Entity_Id :=
1039 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1041 -- Start of processing for Access_Subprogram_Declaration
1044 Check_SPARK_Restriction ("access type is not allowed", T_Def);
1046 -- Associate the Itype node with the inner full-type declaration or
1047 -- subprogram spec or entry body. This is required to handle nested
1048 -- anonymous declarations. For example:
1051 -- (X : access procedure
1052 -- (Y : access procedure
1055 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1056 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1057 N_Private_Type_Declaration,
1058 N_Private_Extension_Declaration,
1059 N_Procedure_Specification,
1060 N_Function_Specification,
1064 Nkind_In (D_Ityp, N_Object_Declaration,
1065 N_Object_Renaming_Declaration,
1066 N_Formal_Object_Declaration,
1067 N_Formal_Type_Declaration,
1068 N_Task_Type_Declaration,
1069 N_Protected_Type_Declaration))
1071 D_Ityp := Parent (D_Ityp);
1072 pragma Assert (D_Ityp /= Empty);
1075 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1077 if Nkind_In (D_Ityp, N_Procedure_Specification,
1078 N_Function_Specification)
1080 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1082 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1083 N_Object_Declaration,
1084 N_Object_Renaming_Declaration,
1085 N_Formal_Type_Declaration)
1087 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1090 if Nkind (T_Def) = N_Access_Function_Definition then
1091 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1093 Acc : constant Node_Id := Result_Definition (T_Def);
1096 if Present (Access_To_Subprogram_Definition (Acc))
1098 Protected_Present (Access_To_Subprogram_Definition (Acc))
1102 Replace_Anonymous_Access_To_Protected_Subprogram
1108 Access_Definition (T_Def, Result_Definition (T_Def)));
1113 Analyze (Result_Definition (T_Def));
1116 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1119 -- If a null exclusion is imposed on the result type, then
1120 -- create a null-excluding itype (an access subtype) and use
1121 -- it as the function's Etype.
1123 if Is_Access_Type (Typ)
1124 and then Null_Exclusion_In_Return_Present (T_Def)
1126 Set_Etype (Desig_Type,
1127 Create_Null_Excluding_Itype
1129 Related_Nod => T_Def,
1130 Scope_Id => Current_Scope));
1133 if From_With_Type (Typ) then
1135 -- AI05-151: Incomplete types are allowed in all basic
1136 -- declarations, including access to subprograms.
1138 if Ada_Version >= Ada_2012 then
1143 ("illegal use of incomplete type&",
1144 Result_Definition (T_Def), Typ);
1147 elsif Ekind (Current_Scope) = E_Package
1148 and then In_Private_Part (Current_Scope)
1150 if Ekind (Typ) = E_Incomplete_Type then
1151 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1153 elsif Is_Class_Wide_Type (Typ)
1154 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1157 (Desig_Type, Private_Dependents (Etype (Typ)));
1161 Set_Etype (Desig_Type, Typ);
1166 if not (Is_Type (Etype (Desig_Type))) then
1168 ("expect type in function specification",
1169 Result_Definition (T_Def));
1173 Set_Etype (Desig_Type, Standard_Void_Type);
1176 if Present (Formals) then
1177 Push_Scope (Desig_Type);
1179 -- A bit of a kludge here. These kludges will be removed when Itypes
1180 -- have proper parent pointers to their declarations???
1182 -- Kludge 1) Link defining_identifier of formals. Required by
1183 -- First_Formal to provide its functionality.
1189 F := First (Formals);
1191 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1192 -- when it is part of an unconstrained type and subtype expansion
1193 -- is disabled. To avoid back-end problems with shared profiles,
1194 -- use previous subprogram type as the designated type.
1197 and then Present (Scope (Defining_Identifier (F)))
1199 Set_Etype (T_Name, T_Name);
1200 Init_Size_Align (T_Name);
1201 Set_Directly_Designated_Type (T_Name,
1202 Scope (Defining_Identifier (F)));
1206 while Present (F) loop
1207 if No (Parent (Defining_Identifier (F))) then
1208 Set_Parent (Defining_Identifier (F), F);
1215 Process_Formals (Formals, Parent (T_Def));
1217 -- Kludge 2) End_Scope requires that the parent pointer be set to
1218 -- something reasonable, but Itypes don't have parent pointers. So
1219 -- we set it and then unset it ???
1221 Set_Parent (Desig_Type, T_Name);
1223 Set_Parent (Desig_Type, Empty);
1226 -- Check for premature usage of the type being defined
1228 Check_For_Premature_Usage (T_Def);
1230 -- The return type and/or any parameter type may be incomplete. Mark
1231 -- the subprogram_type as depending on the incomplete type, so that
1232 -- it can be updated when the full type declaration is seen. This
1233 -- only applies to incomplete types declared in some enclosing scope,
1234 -- not to limited views from other packages.
1236 if Present (Formals) then
1237 Formal := First_Formal (Desig_Type);
1238 while Present (Formal) loop
1239 if Ekind (Formal) /= E_In_Parameter
1240 and then Nkind (T_Def) = N_Access_Function_Definition
1242 Error_Msg_N ("functions can only have IN parameters", Formal);
1245 if Ekind (Etype (Formal)) = E_Incomplete_Type
1246 and then In_Open_Scopes (Scope (Etype (Formal)))
1248 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1249 Set_Has_Delayed_Freeze (Desig_Type);
1252 Next_Formal (Formal);
1256 -- If the return type is incomplete, this is legal as long as the
1257 -- type is declared in the current scope and will be completed in
1258 -- it (rather than being part of limited view).
1260 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1261 and then not Has_Delayed_Freeze (Desig_Type)
1262 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1264 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1265 Set_Has_Delayed_Freeze (Desig_Type);
1268 Check_Delayed_Subprogram (Desig_Type);
1270 if Protected_Present (T_Def) then
1271 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1272 Set_Convention (Desig_Type, Convention_Protected);
1274 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1277 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1279 Set_Etype (T_Name, T_Name);
1280 Init_Size_Align (T_Name);
1281 Set_Directly_Designated_Type (T_Name, Desig_Type);
1283 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1285 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1287 Check_Restriction (No_Access_Subprograms, T_Def);
1288 end Access_Subprogram_Declaration;
1290 ----------------------------
1291 -- Access_Type_Declaration --
1292 ----------------------------
1294 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1295 P : constant Node_Id := Parent (Def);
1296 S : constant Node_Id := Subtype_Indication (Def);
1298 Full_Desig : Entity_Id;
1301 Check_SPARK_Restriction ("access type is not allowed", Def);
1303 -- Check for permissible use of incomplete type
1305 if Nkind (S) /= N_Subtype_Indication then
1308 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1309 Set_Directly_Designated_Type (T, Entity (S));
1311 Set_Directly_Designated_Type (T,
1312 Process_Subtype (S, P, T, 'P'));
1316 Set_Directly_Designated_Type (T,
1317 Process_Subtype (S, P, T, 'P'));
1320 if All_Present (Def) or Constant_Present (Def) then
1321 Set_Ekind (T, E_General_Access_Type);
1323 Set_Ekind (T, E_Access_Type);
1326 Full_Desig := Designated_Type (T);
1328 if Base_Type (Full_Desig) = T then
1329 Error_Msg_N ("access type cannot designate itself", S);
1331 -- In Ada 2005, the type may have a limited view through some unit
1332 -- in its own context, allowing the following circularity that cannot
1333 -- be detected earlier
1335 elsif Is_Class_Wide_Type (Full_Desig)
1336 and then Etype (Full_Desig) = T
1339 ("access type cannot designate its own classwide type", S);
1341 -- Clean up indication of tagged status to prevent cascaded errors
1343 Set_Is_Tagged_Type (T, False);
1348 -- If the type has appeared already in a with_type clause, it is
1349 -- frozen and the pointer size is already set. Else, initialize.
1351 if not From_With_Type (T) then
1352 Init_Size_Align (T);
1355 -- Note that Has_Task is always false, since the access type itself
1356 -- is not a task type. See Einfo for more description on this point.
1357 -- Exactly the same consideration applies to Has_Controlled_Component.
1359 Set_Has_Task (T, False);
1360 Set_Has_Controlled_Component (T, False);
1362 -- Initialize field Finalization_Master explicitly to Empty, to avoid
1363 -- problems where an incomplete view of this entity has been previously
1364 -- established by a limited with and an overlaid version of this field
1365 -- (Stored_Constraint) was initialized for the incomplete view.
1367 -- This reset is performed in most cases except where the access type
1368 -- has been created for the purposes of allocating or deallocating a
1369 -- build-in-place object. Such access types have explicitly set pools
1370 -- and finalization masters.
1372 if No (Associated_Storage_Pool (T)) then
1373 Set_Finalization_Master (T, Empty);
1376 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1379 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1380 Set_Is_Access_Constant (T, Constant_Present (Def));
1381 end Access_Type_Declaration;
1383 ----------------------------------
1384 -- Add_Interface_Tag_Components --
1385 ----------------------------------
1387 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1388 Loc : constant Source_Ptr := Sloc (N);
1392 procedure Add_Tag (Iface : Entity_Id);
1393 -- Add tag for one of the progenitor interfaces
1399 procedure Add_Tag (Iface : Entity_Id) is
1406 pragma Assert (Is_Tagged_Type (Iface)
1407 and then Is_Interface (Iface));
1409 -- This is a reasonable place to propagate predicates
1411 if Has_Predicates (Iface) then
1412 Set_Has_Predicates (Typ);
1416 Make_Component_Definition (Loc,
1417 Aliased_Present => True,
1418 Subtype_Indication =>
1419 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1421 Tag := Make_Temporary (Loc, 'V');
1424 Make_Component_Declaration (Loc,
1425 Defining_Identifier => Tag,
1426 Component_Definition => Def);
1428 Analyze_Component_Declaration (Decl);
1430 Set_Analyzed (Decl);
1431 Set_Ekind (Tag, E_Component);
1433 Set_Is_Aliased (Tag);
1434 Set_Related_Type (Tag, Iface);
1435 Init_Component_Location (Tag);
1437 pragma Assert (Is_Frozen (Iface));
1439 Set_DT_Entry_Count (Tag,
1440 DT_Entry_Count (First_Entity (Iface)));
1442 if No (Last_Tag) then
1445 Insert_After (Last_Tag, Decl);
1450 -- If the ancestor has discriminants we need to give special support
1451 -- to store the offset_to_top value of the secondary dispatch tables.
1452 -- For this purpose we add a supplementary component just after the
1453 -- field that contains the tag associated with each secondary DT.
1455 if Typ /= Etype (Typ)
1456 and then Has_Discriminants (Etype (Typ))
1459 Make_Component_Definition (Loc,
1460 Subtype_Indication =>
1461 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1463 Offset := Make_Temporary (Loc, 'V');
1466 Make_Component_Declaration (Loc,
1467 Defining_Identifier => Offset,
1468 Component_Definition => Def);
1470 Analyze_Component_Declaration (Decl);
1472 Set_Analyzed (Decl);
1473 Set_Ekind (Offset, E_Component);
1474 Set_Is_Aliased (Offset);
1475 Set_Related_Type (Offset, Iface);
1476 Init_Component_Location (Offset);
1477 Insert_After (Last_Tag, Decl);
1488 -- Start of processing for Add_Interface_Tag_Components
1491 if not RTE_Available (RE_Interface_Tag) then
1493 ("(Ada 2005) interface types not supported by this run-time!",
1498 if Ekind (Typ) /= E_Record_Type
1499 or else (Is_Concurrent_Record_Type (Typ)
1500 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1501 or else (not Is_Concurrent_Record_Type (Typ)
1502 and then No (Interfaces (Typ))
1503 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1508 -- Find the current last tag
1510 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1511 Ext := Record_Extension_Part (Type_Definition (N));
1513 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1514 Ext := Type_Definition (N);
1519 if not (Present (Component_List (Ext))) then
1520 Set_Null_Present (Ext, False);
1522 Set_Component_List (Ext,
1523 Make_Component_List (Loc,
1524 Component_Items => L,
1525 Null_Present => False));
1527 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1528 L := Component_Items
1530 (Record_Extension_Part
1531 (Type_Definition (N))));
1533 L := Component_Items
1535 (Type_Definition (N)));
1538 -- Find the last tag component
1541 while Present (Comp) loop
1542 if Nkind (Comp) = N_Component_Declaration
1543 and then Is_Tag (Defining_Identifier (Comp))
1552 -- At this point L references the list of components and Last_Tag
1553 -- references the current last tag (if any). Now we add the tag
1554 -- corresponding with all the interfaces that are not implemented
1557 if Present (Interfaces (Typ)) then
1558 Elmt := First_Elmt (Interfaces (Typ));
1559 while Present (Elmt) loop
1560 Add_Tag (Node (Elmt));
1564 end Add_Interface_Tag_Components;
1566 -------------------------------------
1567 -- Add_Internal_Interface_Entities --
1568 -------------------------------------
1570 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1573 Iface_Elmt : Elmt_Id;
1574 Iface_Prim : Entity_Id;
1575 Ifaces_List : Elist_Id;
1576 New_Subp : Entity_Id := Empty;
1578 Restore_Scope : Boolean := False;
1581 pragma Assert (Ada_Version >= Ada_2005
1582 and then Is_Record_Type (Tagged_Type)
1583 and then Is_Tagged_Type (Tagged_Type)
1584 and then Has_Interfaces (Tagged_Type)
1585 and then not Is_Interface (Tagged_Type));
1587 -- Ensure that the internal entities are added to the scope of the type
1589 if Scope (Tagged_Type) /= Current_Scope then
1590 Push_Scope (Scope (Tagged_Type));
1591 Restore_Scope := True;
1594 Collect_Interfaces (Tagged_Type, Ifaces_List);
1596 Iface_Elmt := First_Elmt (Ifaces_List);
1597 while Present (Iface_Elmt) loop
1598 Iface := Node (Iface_Elmt);
1600 -- Originally we excluded here from this processing interfaces that
1601 -- are parents of Tagged_Type because their primitives are located
1602 -- in the primary dispatch table (and hence no auxiliary internal
1603 -- entities are required to handle secondary dispatch tables in such
1604 -- case). However, these auxiliary entities are also required to
1605 -- handle derivations of interfaces in formals of generics (see
1606 -- Derive_Subprograms).
1608 Elmt := First_Elmt (Primitive_Operations (Iface));
1609 while Present (Elmt) loop
1610 Iface_Prim := Node (Elmt);
1612 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1614 Find_Primitive_Covering_Interface
1615 (Tagged_Type => Tagged_Type,
1616 Iface_Prim => Iface_Prim);
1618 if No (Prim) and then Serious_Errors_Detected > 0 then
1622 pragma Assert (Present (Prim));
1624 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1625 -- differs from the name of the interface primitive then it is
1626 -- a private primitive inherited from a parent type. In such
1627 -- case, given that Tagged_Type covers the interface, the
1628 -- inherited private primitive becomes visible. For such
1629 -- purpose we add a new entity that renames the inherited
1630 -- private primitive.
1632 if Chars (Prim) /= Chars (Iface_Prim) then
1633 pragma Assert (Has_Suffix (Prim, 'P'));
1635 (New_Subp => New_Subp,
1636 Parent_Subp => Iface_Prim,
1637 Derived_Type => Tagged_Type,
1638 Parent_Type => Iface);
1639 Set_Alias (New_Subp, Prim);
1640 Set_Is_Abstract_Subprogram
1641 (New_Subp, Is_Abstract_Subprogram (Prim));
1645 (New_Subp => New_Subp,
1646 Parent_Subp => Iface_Prim,
1647 Derived_Type => Tagged_Type,
1648 Parent_Type => Iface);
1650 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1651 -- associated with interface types. These entities are
1652 -- only registered in the list of primitives of its
1653 -- corresponding tagged type because they are only used
1654 -- to fill the contents of the secondary dispatch tables.
1655 -- Therefore they are removed from the homonym chains.
1657 Set_Is_Hidden (New_Subp);
1658 Set_Is_Internal (New_Subp);
1659 Set_Alias (New_Subp, Prim);
1660 Set_Is_Abstract_Subprogram
1661 (New_Subp, Is_Abstract_Subprogram (Prim));
1662 Set_Interface_Alias (New_Subp, Iface_Prim);
1664 -- Internal entities associated with interface types are
1665 -- only registered in the list of primitives of the tagged
1666 -- type. They are only used to fill the contents of the
1667 -- secondary dispatch tables. Therefore they are not needed
1668 -- in the homonym chains.
1670 Remove_Homonym (New_Subp);
1672 -- Hidden entities associated with interfaces must have set
1673 -- the Has_Delay_Freeze attribute to ensure that, in case of
1674 -- locally defined tagged types (or compiling with static
1675 -- dispatch tables generation disabled) the corresponding
1676 -- entry of the secondary dispatch table is filled when
1677 -- such an entity is frozen.
1679 Set_Has_Delayed_Freeze (New_Subp);
1686 Next_Elmt (Iface_Elmt);
1689 if Restore_Scope then
1692 end Add_Internal_Interface_Entities;
1694 -----------------------------------
1695 -- Analyze_Component_Declaration --
1696 -----------------------------------
1698 procedure Analyze_Component_Declaration (N : Node_Id) is
1699 Id : constant Entity_Id := Defining_Identifier (N);
1700 E : constant Node_Id := Expression (N);
1701 Typ : constant Node_Id :=
1702 Subtype_Indication (Component_Definition (N));
1706 function Contains_POC (Constr : Node_Id) return Boolean;
1707 -- Determines whether a constraint uses the discriminant of a record
1708 -- type thus becoming a per-object constraint (POC).
1710 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1711 -- Typ is the type of the current component, check whether this type is
1712 -- a limited type. Used to validate declaration against that of
1713 -- enclosing record.
1719 function Contains_POC (Constr : Node_Id) return Boolean is
1721 -- Prevent cascaded errors
1723 if Error_Posted (Constr) then
1727 case Nkind (Constr) is
1728 when N_Attribute_Reference =>
1730 Attribute_Name (Constr) = Name_Access
1731 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1733 when N_Discriminant_Association =>
1734 return Denotes_Discriminant (Expression (Constr));
1736 when N_Identifier =>
1737 return Denotes_Discriminant (Constr);
1739 when N_Index_Or_Discriminant_Constraint =>
1744 IDC := First (Constraints (Constr));
1745 while Present (IDC) loop
1747 -- One per-object constraint is sufficient
1749 if Contains_POC (IDC) then
1760 return Denotes_Discriminant (Low_Bound (Constr))
1762 Denotes_Discriminant (High_Bound (Constr));
1764 when N_Range_Constraint =>
1765 return Denotes_Discriminant (Range_Expression (Constr));
1773 ----------------------
1774 -- Is_Known_Limited --
1775 ----------------------
1777 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1778 P : constant Entity_Id := Etype (Typ);
1779 R : constant Entity_Id := Root_Type (Typ);
1782 if Is_Limited_Record (Typ) then
1785 -- If the root type is limited (and not a limited interface)
1786 -- so is the current type
1788 elsif Is_Limited_Record (R)
1790 (not Is_Interface (R)
1791 or else not Is_Limited_Interface (R))
1795 -- Else the type may have a limited interface progenitor, but a
1796 -- limited record parent.
1799 and then Is_Limited_Record (P)
1806 end Is_Known_Limited;
1808 -- Start of processing for Analyze_Component_Declaration
1811 Generate_Definition (Id);
1814 if Present (Typ) then
1815 T := Find_Type_Of_Object
1816 (Subtype_Indication (Component_Definition (N)), N);
1818 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1819 Check_SPARK_Restriction ("subtype mark required", Typ);
1822 -- Ada 2005 (AI-230): Access Definition case
1825 pragma Assert (Present
1826 (Access_Definition (Component_Definition (N))));
1828 T := Access_Definition
1830 N => Access_Definition (Component_Definition (N)));
1831 Set_Is_Local_Anonymous_Access (T);
1833 -- Ada 2005 (AI-254)
1835 if Present (Access_To_Subprogram_Definition
1836 (Access_Definition (Component_Definition (N))))
1837 and then Protected_Present (Access_To_Subprogram_Definition
1839 (Component_Definition (N))))
1841 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1845 -- If the subtype is a constrained subtype of the enclosing record,
1846 -- (which must have a partial view) the back-end does not properly
1847 -- handle the recursion. Rewrite the component declaration with an
1848 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1849 -- the tree directly because side effects have already been removed from
1850 -- discriminant constraints.
1852 if Ekind (T) = E_Access_Subtype
1853 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1854 and then Comes_From_Source (T)
1855 and then Nkind (Parent (T)) = N_Subtype_Declaration
1856 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1859 (Subtype_Indication (Component_Definition (N)),
1860 New_Copy_Tree (Subtype_Indication (Parent (T))));
1861 T := Find_Type_Of_Object
1862 (Subtype_Indication (Component_Definition (N)), N);
1865 -- If the component declaration includes a default expression, then we
1866 -- check that the component is not of a limited type (RM 3.7(5)),
1867 -- and do the special preanalysis of the expression (see section on
1868 -- "Handling of Default and Per-Object Expressions" in the spec of
1872 Check_SPARK_Restriction ("default expression is not allowed", E);
1873 Preanalyze_Spec_Expression (E, T);
1874 Check_Initialization (T, E);
1876 if Ada_Version >= Ada_2005
1877 and then Ekind (T) = E_Anonymous_Access_Type
1878 and then Etype (E) /= Any_Type
1880 -- Check RM 3.9.2(9): "if the expected type for an expression is
1881 -- an anonymous access-to-specific tagged type, then the object
1882 -- designated by the expression shall not be dynamically tagged
1883 -- unless it is a controlling operand in a call on a dispatching
1886 if Is_Tagged_Type (Directly_Designated_Type (T))
1888 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1890 Ekind (Directly_Designated_Type (Etype (E))) =
1894 ("access to specific tagged type required (RM 3.9.2(9))", E);
1897 -- (Ada 2005: AI-230): Accessibility check for anonymous
1900 if Type_Access_Level (Etype (E)) >
1901 Deepest_Type_Access_Level (T)
1904 ("expression has deeper access level than component " &
1905 "(RM 3.10.2 (12.2))", E);
1908 -- The initialization expression is a reference to an access
1909 -- discriminant. The type of the discriminant is always deeper
1910 -- than any access type.
1912 if Ekind (Etype (E)) = E_Anonymous_Access_Type
1913 and then Is_Entity_Name (E)
1914 and then Ekind (Entity (E)) = E_In_Parameter
1915 and then Present (Discriminal_Link (Entity (E)))
1918 ("discriminant has deeper accessibility level than target",
1924 -- The parent type may be a private view with unknown discriminants,
1925 -- and thus unconstrained. Regular components must be constrained.
1927 if Is_Indefinite_Subtype (T) and then Chars (Id) /= Name_uParent then
1928 if Is_Class_Wide_Type (T) then
1930 ("class-wide subtype with unknown discriminants" &
1931 " in component declaration",
1932 Subtype_Indication (Component_Definition (N)));
1935 ("unconstrained subtype in component declaration",
1936 Subtype_Indication (Component_Definition (N)));
1939 -- Components cannot be abstract, except for the special case of
1940 -- the _Parent field (case of extending an abstract tagged type)
1942 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
1943 Error_Msg_N ("type of a component cannot be abstract", N);
1947 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
1949 -- The component declaration may have a per-object constraint, set
1950 -- the appropriate flag in the defining identifier of the subtype.
1952 if Present (Subtype_Indication (Component_Definition (N))) then
1954 Sindic : constant Node_Id :=
1955 Subtype_Indication (Component_Definition (N));
1957 if Nkind (Sindic) = N_Subtype_Indication
1958 and then Present (Constraint (Sindic))
1959 and then Contains_POC (Constraint (Sindic))
1961 Set_Has_Per_Object_Constraint (Id);
1966 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
1967 -- out some static checks.
1969 if Ada_Version >= Ada_2005
1970 and then Can_Never_Be_Null (T)
1972 Null_Exclusion_Static_Checks (N);
1975 -- If this component is private (or depends on a private type), flag the
1976 -- record type to indicate that some operations are not available.
1978 P := Private_Component (T);
1982 -- Check for circular definitions
1984 if P = Any_Type then
1985 Set_Etype (Id, Any_Type);
1987 -- There is a gap in the visibility of operations only if the
1988 -- component type is not defined in the scope of the record type.
1990 elsif Scope (P) = Scope (Current_Scope) then
1993 elsif Is_Limited_Type (P) then
1994 Set_Is_Limited_Composite (Current_Scope);
1997 Set_Is_Private_Composite (Current_Scope);
2002 and then Is_Limited_Type (T)
2003 and then Chars (Id) /= Name_uParent
2004 and then Is_Tagged_Type (Current_Scope)
2006 if Is_Derived_Type (Current_Scope)
2007 and then not Is_Known_Limited (Current_Scope)
2010 ("extension of nonlimited type cannot have limited components",
2013 if Is_Interface (Root_Type (Current_Scope)) then
2015 ("\limitedness is not inherited from limited interface", N);
2016 Error_Msg_N ("\add LIMITED to type indication", N);
2019 Explain_Limited_Type (T, N);
2020 Set_Etype (Id, Any_Type);
2021 Set_Is_Limited_Composite (Current_Scope, False);
2023 elsif not Is_Derived_Type (Current_Scope)
2024 and then not Is_Limited_Record (Current_Scope)
2025 and then not Is_Concurrent_Type (Current_Scope)
2028 ("nonlimited tagged type cannot have limited components", N);
2029 Explain_Limited_Type (T, N);
2030 Set_Etype (Id, Any_Type);
2031 Set_Is_Limited_Composite (Current_Scope, False);
2035 Set_Original_Record_Component (Id, Id);
2037 if Has_Aspects (N) then
2038 Analyze_Aspect_Specifications (N, Id);
2041 Analyze_Dimension (N);
2042 end Analyze_Component_Declaration;
2044 --------------------------
2045 -- Analyze_Declarations --
2046 --------------------------
2048 procedure Analyze_Declarations (L : List_Id) is
2050 Freeze_From : Entity_Id := Empty;
2051 Next_Node : Node_Id;
2054 -- Adjust D not to include implicit label declarations, since these
2055 -- have strange Sloc values that result in elaboration check problems.
2056 -- (They have the sloc of the label as found in the source, and that
2057 -- is ahead of the current declarative part).
2063 procedure Adjust_D is
2065 while Present (Prev (D))
2066 and then Nkind (D) = N_Implicit_Label_Declaration
2072 -- Start of processing for Analyze_Declarations
2075 if Restriction_Check_Required (SPARK) then
2076 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2080 while Present (D) loop
2082 -- Package spec cannot contain a package declaration in SPARK
2084 if Nkind (D) = N_Package_Declaration
2085 and then Nkind (Parent (L)) = N_Package_Specification
2087 Check_SPARK_Restriction
2088 ("package specification cannot contain a package declaration",
2092 -- Complete analysis of declaration
2095 Next_Node := Next (D);
2097 if No (Freeze_From) then
2098 Freeze_From := First_Entity (Current_Scope);
2101 -- At the end of a declarative part, freeze remaining entities
2102 -- declared in it. The end of the visible declarations of package
2103 -- specification is not the end of a declarative part if private
2104 -- declarations are present. The end of a package declaration is a
2105 -- freezing point only if it a library package. A task definition or
2106 -- protected type definition is not a freeze point either. Finally,
2107 -- we do not freeze entities in generic scopes, because there is no
2108 -- code generated for them and freeze nodes will be generated for
2111 -- The end of a package instantiation is not a freeze point, but
2112 -- for now we make it one, because the generic body is inserted
2113 -- (currently) immediately after. Generic instantiations will not
2114 -- be a freeze point once delayed freezing of bodies is implemented.
2115 -- (This is needed in any case for early instantiations ???).
2117 if No (Next_Node) then
2118 if Nkind_In (Parent (L), N_Component_List,
2120 N_Protected_Definition)
2124 elsif Nkind (Parent (L)) /= N_Package_Specification then
2125 if Nkind (Parent (L)) = N_Package_Body then
2126 Freeze_From := First_Entity (Current_Scope);
2130 Freeze_All (Freeze_From, D);
2131 Freeze_From := Last_Entity (Current_Scope);
2133 elsif Scope (Current_Scope) /= Standard_Standard
2134 and then not Is_Child_Unit (Current_Scope)
2135 and then No (Generic_Parent (Parent (L)))
2139 elsif L /= Visible_Declarations (Parent (L))
2140 or else No (Private_Declarations (Parent (L)))
2141 or else Is_Empty_List (Private_Declarations (Parent (L)))
2144 Freeze_All (Freeze_From, D);
2145 Freeze_From := Last_Entity (Current_Scope);
2148 -- If next node is a body then freeze all types before the body.
2149 -- An exception occurs for some expander-generated bodies. If these
2150 -- are generated at places where in general language rules would not
2151 -- allow a freeze point, then we assume that the expander has
2152 -- explicitly checked that all required types are properly frozen,
2153 -- and we do not cause general freezing here. This special circuit
2154 -- is used when the encountered body is marked as having already
2157 -- In all other cases (bodies that come from source, and expander
2158 -- generated bodies that have not been analyzed yet), freeze all
2159 -- types now. Note that in the latter case, the expander must take
2160 -- care to attach the bodies at a proper place in the tree so as to
2161 -- not cause unwanted freezing at that point.
2163 elsif not Analyzed (Next_Node)
2164 and then (Nkind_In (Next_Node, N_Subprogram_Body,
2170 Nkind (Next_Node) in N_Body_Stub)
2173 Freeze_All (Freeze_From, D);
2174 Freeze_From := Last_Entity (Current_Scope);
2180 -- One more thing to do, we need to scan the declarations to check
2181 -- for any precondition/postcondition pragmas (Pre/Post aspects have
2182 -- by this stage been converted into corresponding pragmas). It is
2183 -- at this point that we analyze the expressions in such pragmas,
2184 -- to implement the delayed visibility requirement.
2194 while Present (Decl) loop
2195 if Nkind (Original_Node (Decl)) = N_Subprogram_Declaration then
2196 Spec := Specification (Original_Node (Decl));
2197 Sent := Defining_Unit_Name (Spec);
2199 Prag := Spec_PPC_List (Contract (Sent));
2200 while Present (Prag) loop
2201 Analyze_PPC_In_Decl_Part (Prag, Sent);
2202 Prag := Next_Pragma (Prag);
2205 Check_Subprogram_Contract (Sent);
2207 Prag := Spec_TC_List (Contract (Sent));
2208 while Present (Prag) loop
2209 Analyze_TC_In_Decl_Part (Prag, Sent);
2210 Prag := Next_Pragma (Prag);
2217 end Analyze_Declarations;
2219 -----------------------------------
2220 -- Analyze_Full_Type_Declaration --
2221 -----------------------------------
2223 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2224 Def : constant Node_Id := Type_Definition (N);
2225 Def_Id : constant Entity_Id := Defining_Identifier (N);
2229 Is_Remote : constant Boolean :=
2230 (Is_Remote_Types (Current_Scope)
2231 or else Is_Remote_Call_Interface (Current_Scope))
2232 and then not (In_Private_Part (Current_Scope)
2233 or else In_Package_Body (Current_Scope));
2235 procedure Check_Ops_From_Incomplete_Type;
2236 -- If there is a tagged incomplete partial view of the type, traverse
2237 -- the primitives of the incomplete view and change the type of any
2238 -- controlling formals and result to indicate the full view. The
2239 -- primitives will be added to the full type's primitive operations
2240 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2241 -- is called from Process_Incomplete_Dependents).
2243 ------------------------------------
2244 -- Check_Ops_From_Incomplete_Type --
2245 ------------------------------------
2247 procedure Check_Ops_From_Incomplete_Type is
2254 and then Ekind (Prev) = E_Incomplete_Type
2255 and then Is_Tagged_Type (Prev)
2256 and then Is_Tagged_Type (T)
2258 Elmt := First_Elmt (Primitive_Operations (Prev));
2259 while Present (Elmt) loop
2262 Formal := First_Formal (Op);
2263 while Present (Formal) loop
2264 if Etype (Formal) = Prev then
2265 Set_Etype (Formal, T);
2268 Next_Formal (Formal);
2271 if Etype (Op) = Prev then
2278 end Check_Ops_From_Incomplete_Type;
2280 -- Start of processing for Analyze_Full_Type_Declaration
2283 Prev := Find_Type_Name (N);
2285 -- The full view, if present, now points to the current type
2287 -- Ada 2005 (AI-50217): If the type was previously decorated when
2288 -- imported through a LIMITED WITH clause, it appears as incomplete
2289 -- but has no full view.
2291 if Ekind (Prev) = E_Incomplete_Type
2292 and then Present (Full_View (Prev))
2294 T := Full_View (Prev);
2299 Set_Is_Pure (T, Is_Pure (Current_Scope));
2301 -- We set the flag Is_First_Subtype here. It is needed to set the
2302 -- corresponding flag for the Implicit class-wide-type created
2303 -- during tagged types processing.
2305 Set_Is_First_Subtype (T, True);
2307 -- Only composite types other than array types are allowed to have
2312 -- For derived types, the rule will be checked once we've figured
2313 -- out the parent type.
2315 when N_Derived_Type_Definition =>
2318 -- For record types, discriminants are allowed, unless we are in
2321 when N_Record_Definition =>
2322 if Present (Discriminant_Specifications (N)) then
2323 Check_SPARK_Restriction
2324 ("discriminant type is not allowed",
2326 (First (Discriminant_Specifications (N))));
2330 if Present (Discriminant_Specifications (N)) then
2332 ("elementary or array type cannot have discriminants",
2334 (First (Discriminant_Specifications (N))));
2338 -- Elaborate the type definition according to kind, and generate
2339 -- subsidiary (implicit) subtypes where needed. We skip this if it was
2340 -- already done (this happens during the reanalysis that follows a call
2341 -- to the high level optimizer).
2343 if not Analyzed (T) then
2348 when N_Access_To_Subprogram_Definition =>
2349 Access_Subprogram_Declaration (T, Def);
2351 -- If this is a remote access to subprogram, we must create the
2352 -- equivalent fat pointer type, and related subprograms.
2355 Process_Remote_AST_Declaration (N);
2358 -- Validate categorization rule against access type declaration
2359 -- usually a violation in Pure unit, Shared_Passive unit.
2361 Validate_Access_Type_Declaration (T, N);
2363 when N_Access_To_Object_Definition =>
2364 Access_Type_Declaration (T, Def);
2366 -- Validate categorization rule against access type declaration
2367 -- usually a violation in Pure unit, Shared_Passive unit.
2369 Validate_Access_Type_Declaration (T, N);
2371 -- If we are in a Remote_Call_Interface package and define a
2372 -- RACW, then calling stubs and specific stream attributes
2376 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
2378 Add_RACW_Features (Def_Id);
2381 -- Set no strict aliasing flag if config pragma seen
2383 if Opt.No_Strict_Aliasing then
2384 Set_No_Strict_Aliasing (Base_Type (Def_Id));
2387 when N_Array_Type_Definition =>
2388 Array_Type_Declaration (T, Def);
2390 when N_Derived_Type_Definition =>
2391 Derived_Type_Declaration (T, N, T /= Def_Id);
2393 when N_Enumeration_Type_Definition =>
2394 Enumeration_Type_Declaration (T, Def);
2396 when N_Floating_Point_Definition =>
2397 Floating_Point_Type_Declaration (T, Def);
2399 when N_Decimal_Fixed_Point_Definition =>
2400 Decimal_Fixed_Point_Type_Declaration (T, Def);
2402 when N_Ordinary_Fixed_Point_Definition =>
2403 Ordinary_Fixed_Point_Type_Declaration (T, Def);
2405 when N_Signed_Integer_Type_Definition =>
2406 Signed_Integer_Type_Declaration (T, Def);
2408 when N_Modular_Type_Definition =>
2409 Modular_Type_Declaration (T, Def);
2411 when N_Record_Definition =>
2412 Record_Type_Declaration (T, N, Prev);
2414 -- If declaration has a parse error, nothing to elaborate.
2420 raise Program_Error;
2425 if Etype (T) = Any_Type then
2429 -- Controlled type is not allowed in SPARK
2431 if Is_Visibly_Controlled (T) then
2432 Check_SPARK_Restriction ("controlled type is not allowed", N);
2435 -- Some common processing for all types
2437 Set_Depends_On_Private (T, Has_Private_Component (T));
2438 Check_Ops_From_Incomplete_Type;
2440 -- Both the declared entity, and its anonymous base type if one
2441 -- was created, need freeze nodes allocated.
2444 B : constant Entity_Id := Base_Type (T);
2447 -- In the case where the base type differs from the first subtype, we
2448 -- pre-allocate a freeze node, and set the proper link to the first
2449 -- subtype. Freeze_Entity will use this preallocated freeze node when
2450 -- it freezes the entity.
2452 -- This does not apply if the base type is a generic type, whose
2453 -- declaration is independent of the current derived definition.
2455 if B /= T and then not Is_Generic_Type (B) then
2456 Ensure_Freeze_Node (B);
2457 Set_First_Subtype_Link (Freeze_Node (B), T);
2460 -- A type that is imported through a limited_with clause cannot
2461 -- generate any code, and thus need not be frozen. However, an access
2462 -- type with an imported designated type needs a finalization list,
2463 -- which may be referenced in some other package that has non-limited
2464 -- visibility on the designated type. Thus we must create the
2465 -- finalization list at the point the access type is frozen, to
2466 -- prevent unsatisfied references at link time.
2468 if not From_With_Type (T) or else Is_Access_Type (T) then
2469 Set_Has_Delayed_Freeze (T);
2473 -- Case where T is the full declaration of some private type which has
2474 -- been swapped in Defining_Identifier (N).
2476 if T /= Def_Id and then Is_Private_Type (Def_Id) then
2477 Process_Full_View (N, T, Def_Id);
2479 -- Record the reference. The form of this is a little strange, since
2480 -- the full declaration has been swapped in. So the first parameter
2481 -- here represents the entity to which a reference is made which is
2482 -- the "real" entity, i.e. the one swapped in, and the second
2483 -- parameter provides the reference location.
2485 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
2486 -- since we don't want a complaint about the full type being an
2487 -- unwanted reference to the private type
2490 B : constant Boolean := Has_Pragma_Unreferenced (T);
2492 Set_Has_Pragma_Unreferenced (T, False);
2493 Generate_Reference (T, T, 'c');
2494 Set_Has_Pragma_Unreferenced (T, B);
2497 Set_Completion_Referenced (Def_Id);
2499 -- For completion of incomplete type, process incomplete dependents
2500 -- and always mark the full type as referenced (it is the incomplete
2501 -- type that we get for any real reference).
2503 elsif Ekind (Prev) = E_Incomplete_Type then
2504 Process_Incomplete_Dependents (N, T, Prev);
2505 Generate_Reference (Prev, Def_Id, 'c');
2506 Set_Completion_Referenced (Def_Id);
2508 -- If not private type or incomplete type completion, this is a real
2509 -- definition of a new entity, so record it.
2512 Generate_Definition (Def_Id);
2515 if Chars (Scope (Def_Id)) = Name_System
2516 and then Chars (Def_Id) = Name_Address
2517 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
2519 Set_Is_Descendent_Of_Address (Def_Id);
2520 Set_Is_Descendent_Of_Address (Base_Type (Def_Id));
2521 Set_Is_Descendent_Of_Address (Prev);
2524 Set_Optimize_Alignment_Flags (Def_Id);
2525 Check_Eliminated (Def_Id);
2527 -- If the declaration is a completion and aspects are present, apply
2528 -- them to the entity for the type which is currently the partial
2529 -- view, but which is the one that will be frozen.
2531 if Has_Aspects (N) then
2532 if Prev /= Def_Id then
2533 Analyze_Aspect_Specifications (N, Prev);
2535 Analyze_Aspect_Specifications (N, Def_Id);
2538 end Analyze_Full_Type_Declaration;
2540 ----------------------------------
2541 -- Analyze_Incomplete_Type_Decl --
2542 ----------------------------------
2544 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
2545 F : constant Boolean := Is_Pure (Current_Scope);
2549 Check_SPARK_Restriction ("incomplete type is not allowed", N);
2551 Generate_Definition (Defining_Identifier (N));
2553 -- Process an incomplete declaration. The identifier must not have been
2554 -- declared already in the scope. However, an incomplete declaration may
2555 -- appear in the private part of a package, for a private type that has
2556 -- already been declared.
2558 -- In this case, the discriminants (if any) must match
2560 T := Find_Type_Name (N);
2562 Set_Ekind (T, E_Incomplete_Type);
2563 Init_Size_Align (T);
2564 Set_Is_First_Subtype (T, True);
2567 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
2568 -- incomplete types.
2570 if Tagged_Present (N) then
2571 Set_Is_Tagged_Type (T);
2572 Make_Class_Wide_Type (T);
2573 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2578 Set_Stored_Constraint (T, No_Elist);
2580 if Present (Discriminant_Specifications (N)) then
2581 Process_Discriminants (N);
2586 -- If the type has discriminants, non-trivial subtypes may be
2587 -- declared before the full view of the type. The full views of those
2588 -- subtypes will be built after the full view of the type.
2590 Set_Private_Dependents (T, New_Elmt_List);
2592 end Analyze_Incomplete_Type_Decl;
2594 -----------------------------------
2595 -- Analyze_Interface_Declaration --
2596 -----------------------------------
2598 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
2599 CW : constant Entity_Id := Class_Wide_Type (T);
2602 Set_Is_Tagged_Type (T);
2604 Set_Is_Limited_Record (T, Limited_Present (Def)
2605 or else Task_Present (Def)
2606 or else Protected_Present (Def)
2607 or else Synchronized_Present (Def));
2609 -- Type is abstract if full declaration carries keyword, or if previous
2610 -- partial view did.
2612 Set_Is_Abstract_Type (T);
2613 Set_Is_Interface (T);
2615 -- Type is a limited interface if it includes the keyword limited, task,
2616 -- protected, or synchronized.
2618 Set_Is_Limited_Interface
2619 (T, Limited_Present (Def)
2620 or else Protected_Present (Def)
2621 or else Synchronized_Present (Def)
2622 or else Task_Present (Def));
2624 Set_Interfaces (T, New_Elmt_List);
2625 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2627 -- Complete the decoration of the class-wide entity if it was already
2628 -- built (i.e. during the creation of the limited view)
2630 if Present (CW) then
2631 Set_Is_Interface (CW);
2632 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
2635 -- Check runtime support for synchronized interfaces
2637 if VM_Target = No_VM
2638 and then (Is_Task_Interface (T)
2639 or else Is_Protected_Interface (T)
2640 or else Is_Synchronized_Interface (T))
2641 and then not RTE_Available (RE_Select_Specific_Data)
2643 Error_Msg_CRT ("synchronized interfaces", T);
2645 end Analyze_Interface_Declaration;
2647 -----------------------------
2648 -- Analyze_Itype_Reference --
2649 -----------------------------
2651 -- Nothing to do. This node is placed in the tree only for the benefit of
2652 -- back end processing, and has no effect on the semantic processing.
2654 procedure Analyze_Itype_Reference (N : Node_Id) is
2656 pragma Assert (Is_Itype (Itype (N)));
2658 end Analyze_Itype_Reference;
2660 --------------------------------
2661 -- Analyze_Number_Declaration --
2662 --------------------------------
2664 procedure Analyze_Number_Declaration (N : Node_Id) is
2665 Id : constant Entity_Id := Defining_Identifier (N);
2666 E : constant Node_Id := Expression (N);
2668 Index : Interp_Index;
2672 Generate_Definition (Id);
2675 -- This is an optimization of a common case of an integer literal
2677 if Nkind (E) = N_Integer_Literal then
2678 Set_Is_Static_Expression (E, True);
2679 Set_Etype (E, Universal_Integer);
2681 Set_Etype (Id, Universal_Integer);
2682 Set_Ekind (Id, E_Named_Integer);
2683 Set_Is_Frozen (Id, True);
2687 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2689 -- Process expression, replacing error by integer zero, to avoid
2690 -- cascaded errors or aborts further along in the processing
2692 -- Replace Error by integer zero, which seems least likely to cause
2696 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
2697 Set_Error_Posted (E);
2702 -- Verify that the expression is static and numeric. If
2703 -- the expression is overloaded, we apply the preference
2704 -- rule that favors root numeric types.
2706 if not Is_Overloaded (E) then
2712 Get_First_Interp (E, Index, It);
2713 while Present (It.Typ) loop
2714 if (Is_Integer_Type (It.Typ)
2715 or else Is_Real_Type (It.Typ))
2716 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
2718 if T = Any_Type then
2721 elsif It.Typ = Universal_Real
2722 or else It.Typ = Universal_Integer
2724 -- Choose universal interpretation over any other
2731 Get_Next_Interp (Index, It);
2735 if Is_Integer_Type (T) then
2737 Set_Etype (Id, Universal_Integer);
2738 Set_Ekind (Id, E_Named_Integer);
2740 elsif Is_Real_Type (T) then
2742 -- Because the real value is converted to universal_real, this is a
2743 -- legal context for a universal fixed expression.
2745 if T = Universal_Fixed then
2747 Loc : constant Source_Ptr := Sloc (N);
2748 Conv : constant Node_Id := Make_Type_Conversion (Loc,
2750 New_Occurrence_Of (Universal_Real, Loc),
2751 Expression => Relocate_Node (E));
2758 elsif T = Any_Fixed then
2759 Error_Msg_N ("illegal context for mixed mode operation", E);
2761 -- Expression is of the form : universal_fixed * integer. Try to
2762 -- resolve as universal_real.
2764 T := Universal_Real;
2769 Set_Etype (Id, Universal_Real);
2770 Set_Ekind (Id, E_Named_Real);
2773 Wrong_Type (E, Any_Numeric);
2777 Set_Ekind (Id, E_Constant);
2778 Set_Never_Set_In_Source (Id, True);
2779 Set_Is_True_Constant (Id, True);
2783 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
2784 Set_Etype (E, Etype (Id));
2787 if not Is_OK_Static_Expression (E) then
2788 Flag_Non_Static_Expr
2789 ("non-static expression used in number declaration!", E);
2790 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
2791 Set_Etype (E, Any_Type);
2793 end Analyze_Number_Declaration;
2795 --------------------------------
2796 -- Analyze_Object_Declaration --
2797 --------------------------------
2799 procedure Analyze_Object_Declaration (N : Node_Id) is
2800 Loc : constant Source_Ptr := Sloc (N);
2801 Id : constant Entity_Id := Defining_Identifier (N);
2805 E : Node_Id := Expression (N);
2806 -- E is set to Expression (N) throughout this routine. When
2807 -- Expression (N) is modified, E is changed accordingly.
2809 Prev_Entity : Entity_Id := Empty;
2811 function Count_Tasks (T : Entity_Id) return Uint;
2812 -- This function is called when a non-generic library level object of a
2813 -- task type is declared. Its function is to count the static number of
2814 -- tasks declared within the type (it is only called if Has_Tasks is set
2815 -- for T). As a side effect, if an array of tasks with non-static bounds
2816 -- or a variant record type is encountered, Check_Restrictions is called
2817 -- indicating the count is unknown.
2823 function Count_Tasks (T : Entity_Id) return Uint is
2829 if Is_Task_Type (T) then
2832 elsif Is_Record_Type (T) then
2833 if Has_Discriminants (T) then
2834 Check_Restriction (Max_Tasks, N);
2839 C := First_Component (T);
2840 while Present (C) loop
2841 V := V + Count_Tasks (Etype (C));
2848 elsif Is_Array_Type (T) then
2849 X := First_Index (T);
2850 V := Count_Tasks (Component_Type (T));
2851 while Present (X) loop
2854 if not Is_Static_Subtype (C) then
2855 Check_Restriction (Max_Tasks, N);
2858 V := V * (UI_Max (Uint_0,
2859 Expr_Value (Type_High_Bound (C)) -
2860 Expr_Value (Type_Low_Bound (C)) + Uint_1));
2873 -- Start of processing for Analyze_Object_Declaration
2876 -- There are three kinds of implicit types generated by an
2877 -- object declaration:
2879 -- 1. Those generated by the original Object Definition
2881 -- 2. Those generated by the Expression
2883 -- 3. Those used to constrain the Object Definition with the
2884 -- expression constraints when the definition is unconstrained.
2886 -- They must be generated in this order to avoid order of elaboration
2887 -- issues. Thus the first step (after entering the name) is to analyze
2888 -- the object definition.
2890 if Constant_Present (N) then
2891 Prev_Entity := Current_Entity_In_Scope (Id);
2893 if Present (Prev_Entity)
2896 -- If the homograph is an implicit subprogram, it is overridden
2897 -- by the current declaration.
2899 ((Is_Overloadable (Prev_Entity)
2900 and then Is_Inherited_Operation (Prev_Entity))
2902 -- The current object is a discriminal generated for an entry
2903 -- family index. Even though the index is a constant, in this
2904 -- particular context there is no true constant redeclaration.
2905 -- Enter_Name will handle the visibility.
2908 (Is_Discriminal (Id)
2909 and then Ekind (Discriminal_Link (Id)) =
2910 E_Entry_Index_Parameter)
2912 -- The current object is the renaming for a generic declared
2913 -- within the instance.
2916 (Ekind (Prev_Entity) = E_Package
2917 and then Nkind (Parent (Prev_Entity)) =
2918 N_Package_Renaming_Declaration
2919 and then not Comes_From_Source (Prev_Entity)
2920 and then Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
2922 Prev_Entity := Empty;
2926 if Present (Prev_Entity) then
2927 Constant_Redeclaration (Id, N, T);
2929 Generate_Reference (Prev_Entity, Id, 'c');
2930 Set_Completion_Referenced (Id);
2932 if Error_Posted (N) then
2934 -- Type mismatch or illegal redeclaration, Do not analyze
2935 -- expression to avoid cascaded errors.
2937 T := Find_Type_Of_Object (Object_Definition (N), N);
2939 Set_Ekind (Id, E_Variable);
2943 -- In the normal case, enter identifier at the start to catch premature
2944 -- usage in the initialization expression.
2947 Generate_Definition (Id);
2950 Mark_Coextensions (N, Object_Definition (N));
2952 T := Find_Type_Of_Object (Object_Definition (N), N);
2954 if Nkind (Object_Definition (N)) = N_Access_Definition
2956 (Access_To_Subprogram_Definition (Object_Definition (N)))
2957 and then Protected_Present
2958 (Access_To_Subprogram_Definition (Object_Definition (N)))
2960 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2963 if Error_Posted (Id) then
2965 Set_Ekind (Id, E_Variable);
2970 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2971 -- out some static checks
2973 if Ada_Version >= Ada_2005
2974 and then Can_Never_Be_Null (T)
2976 -- In case of aggregates we must also take care of the correct
2977 -- initialization of nested aggregates bug this is done at the
2978 -- point of the analysis of the aggregate (see sem_aggr.adb)
2980 if Present (Expression (N))
2981 and then Nkind (Expression (N)) = N_Aggregate
2987 Save_Typ : constant Entity_Id := Etype (Id);
2989 Set_Etype (Id, T); -- Temp. decoration for static checks
2990 Null_Exclusion_Static_Checks (N);
2991 Set_Etype (Id, Save_Typ);
2996 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2998 -- If deferred constant, make sure context is appropriate. We detect
2999 -- a deferred constant as a constant declaration with no expression.
3000 -- A deferred constant can appear in a package body if its completion
3001 -- is by means of an interface pragma.
3003 if Constant_Present (N)
3006 -- A deferred constant may appear in the declarative part of the
3007 -- following constructs:
3011 -- extended return statements
3014 -- subprogram bodies
3017 -- When declared inside a package spec, a deferred constant must be
3018 -- completed by a full constant declaration or pragma Import. In all
3019 -- other cases, the only proper completion is pragma Import. Extended
3020 -- return statements are flagged as invalid contexts because they do
3021 -- not have a declarative part and so cannot accommodate the pragma.
3023 if Ekind (Current_Scope) = E_Return_Statement then
3025 ("invalid context for deferred constant declaration (RM 7.4)",
3028 ("\declaration requires an initialization expression",
3030 Set_Constant_Present (N, False);
3032 -- In Ada 83, deferred constant must be of private type
3034 elsif not Is_Private_Type (T) then
3035 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
3037 ("(Ada 83) deferred constant must be private type", N);
3041 -- If not a deferred constant, then object declaration freezes its type
3044 Check_Fully_Declared (T, N);
3045 Freeze_Before (N, T);
3048 -- If the object was created by a constrained array definition, then
3049 -- set the link in both the anonymous base type and anonymous subtype
3050 -- that are built to represent the array type to point to the object.
3052 if Nkind (Object_Definition (Declaration_Node (Id))) =
3053 N_Constrained_Array_Definition
3055 Set_Related_Array_Object (T, Id);
3056 Set_Related_Array_Object (Base_Type (T), Id);
3059 -- Special checks for protected objects not at library level
3061 if Is_Protected_Type (T)
3062 and then not Is_Library_Level_Entity (Id)
3064 Check_Restriction (No_Local_Protected_Objects, Id);
3066 -- Protected objects with interrupt handlers must be at library level
3068 -- Ada 2005: this test is not needed (and the corresponding clause
3069 -- in the RM is removed) because accessibility checks are sufficient
3070 -- to make handlers not at the library level illegal.
3072 if Has_Interrupt_Handler (T)
3073 and then Ada_Version < Ada_2005
3076 ("interrupt object can only be declared at library level", Id);
3080 -- The actual subtype of the object is the nominal subtype, unless
3081 -- the nominal one is unconstrained and obtained from the expression.
3085 -- These checks should be performed before the initialization expression
3086 -- is considered, so that the Object_Definition node is still the same
3087 -- as in source code.
3089 -- In SPARK, the nominal subtype shall be given by a subtype mark and
3090 -- shall not be unconstrained. (The only exception to this is the
3091 -- admission of declarations of constants of type String.)
3094 Nkind_In (Object_Definition (N), N_Identifier, N_Expanded_Name)
3096 Check_SPARK_Restriction
3097 ("subtype mark required", Object_Definition (N));
3099 elsif Is_Array_Type (T)
3100 and then not Is_Constrained (T)
3101 and then T /= Standard_String
3103 Check_SPARK_Restriction
3104 ("subtype mark of constrained type expected",
3105 Object_Definition (N));
3108 -- There are no aliased objects in SPARK
3110 if Aliased_Present (N) then
3111 Check_SPARK_Restriction ("aliased object is not allowed", N);
3114 -- Process initialization expression if present and not in error
3116 if Present (E) and then E /= Error then
3118 -- Generate an error in case of CPP class-wide object initialization.
3119 -- Required because otherwise the expansion of the class-wide
3120 -- assignment would try to use 'size to initialize the object
3121 -- (primitive that is not available in CPP tagged types).
3123 if Is_Class_Wide_Type (Act_T)
3125 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3127 (Present (Full_View (Root_Type (Etype (Act_T))))
3129 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3132 ("predefined assignment not available for 'C'P'P tagged types",
3136 Mark_Coextensions (N, E);
3139 -- In case of errors detected in the analysis of the expression,
3140 -- decorate it with the expected type to avoid cascaded errors
3142 if No (Etype (E)) then
3146 -- If an initialization expression is present, then we set the
3147 -- Is_True_Constant flag. It will be reset if this is a variable
3148 -- and it is indeed modified.
3150 Set_Is_True_Constant (Id, True);
3152 -- If we are analyzing a constant declaration, set its completion
3153 -- flag after analyzing and resolving the expression.
3155 if Constant_Present (N) then
3156 Set_Has_Completion (Id);
3159 -- Set type and resolve (type may be overridden later on)
3164 -- If E is null and has been replaced by an N_Raise_Constraint_Error
3165 -- node (which was marked already-analyzed), we need to set the type
3166 -- to something other than Any_Access in order to keep gigi happy.
3168 if Etype (E) = Any_Access then
3172 -- If the object is an access to variable, the initialization
3173 -- expression cannot be an access to constant.
3175 if Is_Access_Type (T)
3176 and then not Is_Access_Constant (T)
3177 and then Is_Access_Type (Etype (E))
3178 and then Is_Access_Constant (Etype (E))
3181 ("access to variable cannot be initialized "
3182 & "with an access-to-constant expression", E);
3185 if not Assignment_OK (N) then
3186 Check_Initialization (T, E);
3189 Check_Unset_Reference (E);
3191 -- If this is a variable, then set current value. If this is a
3192 -- declared constant of a scalar type with a static expression,
3193 -- indicate that it is always valid.
3195 if not Constant_Present (N) then
3196 if Compile_Time_Known_Value (E) then
3197 Set_Current_Value (Id, E);
3200 elsif Is_Scalar_Type (T)
3201 and then Is_OK_Static_Expression (E)
3203 Set_Is_Known_Valid (Id);
3206 -- Deal with setting of null flags
3208 if Is_Access_Type (T) then
3209 if Known_Non_Null (E) then
3210 Set_Is_Known_Non_Null (Id, True);
3211 elsif Known_Null (E)
3212 and then not Can_Never_Be_Null (Id)
3214 Set_Is_Known_Null (Id, True);
3218 -- Check incorrect use of dynamically tagged expressions.
3220 if Is_Tagged_Type (T) then
3221 Check_Dynamically_Tagged_Expression
3227 Apply_Scalar_Range_Check (E, T);
3228 Apply_Static_Length_Check (E, T);
3230 if Nkind (Original_Node (N)) = N_Object_Declaration
3231 and then Comes_From_Source (Original_Node (N))
3233 -- Only call test if needed
3235 and then Restriction_Check_Required (SPARK)
3236 and then not Is_SPARK_Initialization_Expr (E)
3238 Check_SPARK_Restriction
3239 ("initialization expression is not appropriate", E);
3243 -- If the No_Streams restriction is set, check that the type of the
3244 -- object is not, and does not contain, any subtype derived from
3245 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
3246 -- Has_Stream just for efficiency reasons. There is no point in
3247 -- spending time on a Has_Stream check if the restriction is not set.
3249 if Restriction_Check_Required (No_Streams) then
3250 if Has_Stream (T) then
3251 Check_Restriction (No_Streams, N);
3255 -- Deal with predicate check before we start to do major rewriting.
3256 -- it is OK to initialize and then check the initialized value, since
3257 -- the object goes out of scope if we get a predicate failure. Note
3258 -- that we do this in the analyzer and not the expander because the
3259 -- analyzer does some substantial rewriting in some cases.
3261 -- We need a predicate check if the type has predicates, and if either
3262 -- there is an initializing expression, or for default initialization
3263 -- when we have at least one case of an explicit default initial value.
3265 if not Suppress_Assignment_Checks (N)
3266 and then Present (Predicate_Function (T))
3270 Is_Partially_Initialized_Type (T, Include_Implicit => False))
3273 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
3276 -- Case of unconstrained type
3278 if Is_Indefinite_Subtype (T) then
3280 -- In SPARK, a declaration of unconstrained type is allowed
3281 -- only for constants of type string.
3283 if Is_String_Type (T) and then not Constant_Present (N) then
3284 Check_SPARK_Restriction
3285 ("declaration of object of unconstrained type not allowed",
3289 -- Nothing to do in deferred constant case
3291 if Constant_Present (N) and then No (E) then
3294 -- Case of no initialization present
3297 if No_Initialization (N) then
3300 elsif Is_Class_Wide_Type (T) then
3302 ("initialization required in class-wide declaration ", N);
3306 ("unconstrained subtype not allowed (need initialization)",
3307 Object_Definition (N));
3309 if Is_Record_Type (T) and then Has_Discriminants (T) then
3311 ("\provide initial value or explicit discriminant values",
3312 Object_Definition (N));
3315 ("\or give default discriminant values for type&",
3316 Object_Definition (N), T);
3318 elsif Is_Array_Type (T) then
3320 ("\provide initial value or explicit array bounds",
3321 Object_Definition (N));
3325 -- Case of initialization present but in error. Set initial
3326 -- expression as absent (but do not make above complaints)
3328 elsif E = Error then
3329 Set_Expression (N, Empty);
3332 -- Case of initialization present
3335 -- Check restrictions in Ada 83
3337 if not Constant_Present (N) then
3339 -- Unconstrained variables not allowed in Ada 83 mode
3341 if Ada_Version = Ada_83
3342 and then Comes_From_Source (Object_Definition (N))
3345 ("(Ada 83) unconstrained variable not allowed",
3346 Object_Definition (N));
3350 -- Now we constrain the variable from the initializing expression
3352 -- If the expression is an aggregate, it has been expanded into
3353 -- individual assignments. Retrieve the actual type from the
3354 -- expanded construct.
3356 if Is_Array_Type (T)
3357 and then No_Initialization (N)
3358 and then Nkind (Original_Node (E)) = N_Aggregate
3362 -- In case of class-wide interface object declarations we delay
3363 -- the generation of the equivalent record type declarations until
3364 -- its expansion because there are cases in they are not required.
3366 elsif Is_Interface (T) then
3370 Expand_Subtype_From_Expr (N, T, Object_Definition (N), E);
3371 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
3374 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
3376 if Aliased_Present (N) then
3377 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3380 Freeze_Before (N, Act_T);
3381 Freeze_Before (N, T);
3384 elsif Is_Array_Type (T)
3385 and then No_Initialization (N)
3386 and then Nkind (Original_Node (E)) = N_Aggregate
3388 if not Is_Entity_Name (Object_Definition (N)) then
3390 Check_Compile_Time_Size (Act_T);
3392 if Aliased_Present (N) then
3393 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3397 -- When the given object definition and the aggregate are specified
3398 -- independently, and their lengths might differ do a length check.
3399 -- This cannot happen if the aggregate is of the form (others =>...)
3401 if not Is_Constrained (T) then
3404 elsif Nkind (E) = N_Raise_Constraint_Error then
3406 -- Aggregate is statically illegal. Place back in declaration
3408 Set_Expression (N, E);
3409 Set_No_Initialization (N, False);
3411 elsif T = Etype (E) then
3414 elsif Nkind (E) = N_Aggregate
3415 and then Present (Component_Associations (E))
3416 and then Present (Choices (First (Component_Associations (E))))
3417 and then Nkind (First
3418 (Choices (First (Component_Associations (E))))) = N_Others_Choice
3423 Apply_Length_Check (E, T);
3426 -- If the type is limited unconstrained with defaulted discriminants and
3427 -- there is no expression, then the object is constrained by the
3428 -- defaults, so it is worthwhile building the corresponding subtype.
3430 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
3431 and then not Is_Constrained (T)
3432 and then Has_Discriminants (T)
3435 Act_T := Build_Default_Subtype (T, N);
3437 -- Ada 2005: a limited object may be initialized by means of an
3438 -- aggregate. If the type has default discriminants it has an
3439 -- unconstrained nominal type, Its actual subtype will be obtained
3440 -- from the aggregate, and not from the default discriminants.
3445 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
3447 elsif Present (Underlying_Type (T))
3448 and then not Is_Constrained (Underlying_Type (T))
3449 and then Has_Discriminants (Underlying_Type (T))
3450 and then Nkind (E) = N_Function_Call
3451 and then Constant_Present (N)
3453 -- The back-end has problems with constants of a discriminated type
3454 -- with defaults, if the initial value is a function call. We
3455 -- generate an intermediate temporary for the result of the call.
3456 -- It is unclear why this should make it acceptable to gcc. ???
3458 Remove_Side_Effects (E);
3460 -- If this is a constant declaration of an unconstrained type and
3461 -- the initialization is an aggregate, we can use the subtype of the
3462 -- aggregate for the declared entity because it is immutable.
3464 elsif not Is_Constrained (T)
3465 and then Has_Discriminants (T)
3466 and then Constant_Present (N)
3467 and then not Has_Unchecked_Union (T)
3468 and then Nkind (E) = N_Aggregate
3473 -- Check No_Wide_Characters restriction
3475 Check_Wide_Character_Restriction (T, Object_Definition (N));
3477 -- Indicate this is not set in source. Certainly true for constants, and
3478 -- true for variables so far (will be reset for a variable if and when
3479 -- we encounter a modification in the source).
3481 Set_Never_Set_In_Source (Id, True);
3483 -- Now establish the proper kind and type of the object
3485 if Constant_Present (N) then
3486 Set_Ekind (Id, E_Constant);
3487 Set_Is_True_Constant (Id, True);
3490 Set_Ekind (Id, E_Variable);
3492 -- A variable is set as shared passive if it appears in a shared
3493 -- passive package, and is at the outer level. This is not done for
3494 -- entities generated during expansion, because those are always
3495 -- manipulated locally.
3497 if Is_Shared_Passive (Current_Scope)
3498 and then Is_Library_Level_Entity (Id)
3499 and then Comes_From_Source (Id)
3501 Set_Is_Shared_Passive (Id);
3502 Check_Shared_Var (Id, T, N);
3505 -- Set Has_Initial_Value if initializing expression present. Note
3506 -- that if there is no initializing expression, we leave the state
3507 -- of this flag unchanged (usually it will be False, but notably in
3508 -- the case of exception choice variables, it will already be true).
3511 Set_Has_Initial_Value (Id, True);
3515 -- Initialize alignment and size and capture alignment setting
3517 Init_Alignment (Id);
3519 Set_Optimize_Alignment_Flags (Id);
3521 -- Deal with aliased case
3523 if Aliased_Present (N) then
3524 Set_Is_Aliased (Id);
3526 -- If the object is aliased and the type is unconstrained with
3527 -- defaulted discriminants and there is no expression, then the
3528 -- object is constrained by the defaults, so it is worthwhile
3529 -- building the corresponding subtype.
3531 -- Ada 2005 (AI-363): If the aliased object is discriminated and
3532 -- unconstrained, then only establish an actual subtype if the
3533 -- nominal subtype is indefinite. In definite cases the object is
3534 -- unconstrained in Ada 2005.
3537 and then Is_Record_Type (T)
3538 and then not Is_Constrained (T)
3539 and then Has_Discriminants (T)
3540 and then (Ada_Version < Ada_2005 or else Is_Indefinite_Subtype (T))
3542 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
3546 -- Now we can set the type of the object
3548 Set_Etype (Id, Act_T);
3550 -- Deal with controlled types
3552 if Has_Controlled_Component (Etype (Id))
3553 or else Is_Controlled (Etype (Id))
3555 if not Is_Library_Level_Entity (Id) then
3556 Check_Restriction (No_Nested_Finalization, N);
3558 Validate_Controlled_Object (Id);
3561 -- Generate a warning when an initialization causes an obvious ABE
3562 -- violation. If the init expression is a simple aggregate there
3563 -- shouldn't be any initialize/adjust call generated. This will be
3564 -- true as soon as aggregates are built in place when possible.
3566 -- ??? at the moment we do not generate warnings for temporaries
3567 -- created for those aggregates although Program_Error might be
3568 -- generated if compiled with -gnato.
3570 if Is_Controlled (Etype (Id))
3571 and then Comes_From_Source (Id)
3574 BT : constant Entity_Id := Base_Type (Etype (Id));
3576 Implicit_Call : Entity_Id;
3577 pragma Warnings (Off, Implicit_Call);
3578 -- ??? what is this for (never referenced!)
3580 function Is_Aggr (N : Node_Id) return Boolean;
3581 -- Check that N is an aggregate
3587 function Is_Aggr (N : Node_Id) return Boolean is
3589 case Nkind (Original_Node (N)) is
3590 when N_Aggregate | N_Extension_Aggregate =>
3593 when N_Qualified_Expression |
3595 N_Unchecked_Type_Conversion =>
3596 return Is_Aggr (Expression (Original_Node (N)));
3604 -- If no underlying type, we already are in an error situation.
3605 -- Do not try to add a warning since we do not have access to
3608 if No (Underlying_Type (BT)) then
3609 Implicit_Call := Empty;
3611 -- A generic type does not have usable primitive operators.
3612 -- Initialization calls are built for instances.
3614 elsif Is_Generic_Type (BT) then
3615 Implicit_Call := Empty;
3617 -- If the init expression is not an aggregate, an adjust call
3618 -- will be generated
3620 elsif Present (E) and then not Is_Aggr (E) then
3621 Implicit_Call := Find_Prim_Op (BT, Name_Adjust);
3623 -- If no init expression and we are not in the deferred
3624 -- constant case, an Initialize call will be generated
3626 elsif No (E) and then not Constant_Present (N) then
3627 Implicit_Call := Find_Prim_Op (BT, Name_Initialize);
3630 Implicit_Call := Empty;
3636 if Has_Task (Etype (Id)) then
3637 Check_Restriction (No_Tasking, N);
3639 -- Deal with counting max tasks
3641 -- Nothing to do if inside a generic
3643 if Inside_A_Generic then
3646 -- If library level entity, then count tasks
3648 elsif Is_Library_Level_Entity (Id) then
3649 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
3651 -- If not library level entity, then indicate we don't know max
3652 -- tasks and also check task hierarchy restriction and blocking
3653 -- operation (since starting a task is definitely blocking!)
3656 Check_Restriction (Max_Tasks, N);
3657 Check_Restriction (No_Task_Hierarchy, N);
3658 Check_Potentially_Blocking_Operation (N);
3661 -- A rather specialized test. If we see two tasks being declared
3662 -- of the same type in the same object declaration, and the task
3663 -- has an entry with an address clause, we know that program error
3664 -- will be raised at run time since we can't have two tasks with
3665 -- entries at the same address.
3667 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
3672 E := First_Entity (Etype (Id));
3673 while Present (E) loop
3674 if Ekind (E) = E_Entry
3675 and then Present (Get_Attribute_Definition_Clause
3676 (E, Attribute_Address))
3679 ("?more than one task with same entry address", N);
3681 ("\?Program_Error will be raised at run time", N);
3683 Make_Raise_Program_Error (Loc,
3684 Reason => PE_Duplicated_Entry_Address));
3694 -- Some simple constant-propagation: if the expression is a constant
3695 -- string initialized with a literal, share the literal. This avoids
3699 and then Is_Entity_Name (E)
3700 and then Ekind (Entity (E)) = E_Constant
3701 and then Base_Type (Etype (E)) = Standard_String
3704 Val : constant Node_Id := Constant_Value (Entity (E));
3707 and then Nkind (Val) = N_String_Literal
3709 Rewrite (E, New_Copy (Val));
3714 -- Another optimization: if the nominal subtype is unconstrained and
3715 -- the expression is a function call that returns an unconstrained
3716 -- type, rewrite the declaration as a renaming of the result of the
3717 -- call. The exceptions below are cases where the copy is expected,
3718 -- either by the back end (Aliased case) or by the semantics, as for
3719 -- initializing controlled types or copying tags for classwide types.
3722 and then Nkind (E) = N_Explicit_Dereference
3723 and then Nkind (Original_Node (E)) = N_Function_Call
3724 and then not Is_Library_Level_Entity (Id)
3725 and then not Is_Constrained (Underlying_Type (T))
3726 and then not Is_Aliased (Id)
3727 and then not Is_Class_Wide_Type (T)
3728 and then not Is_Controlled (T)
3729 and then not Has_Controlled_Component (Base_Type (T))
3730 and then Expander_Active
3733 Make_Object_Renaming_Declaration (Loc,
3734 Defining_Identifier => Id,
3735 Access_Definition => Empty,
3736 Subtype_Mark => New_Occurrence_Of
3737 (Base_Type (Etype (Id)), Loc),
3740 Set_Renamed_Object (Id, E);
3742 -- Force generation of debugging information for the constant and for
3743 -- the renamed function call.
3745 Set_Debug_Info_Needed (Id);
3746 Set_Debug_Info_Needed (Entity (Prefix (E)));
3749 if Present (Prev_Entity)
3750 and then Is_Frozen (Prev_Entity)
3751 and then not Error_Posted (Id)
3753 Error_Msg_N ("full constant declaration appears too late", N);
3756 Check_Eliminated (Id);
3758 -- Deal with setting In_Private_Part flag if in private part
3760 if Ekind (Scope (Id)) = E_Package
3761 and then In_Private_Part (Scope (Id))
3763 Set_In_Private_Part (Id);
3766 -- Check for violation of No_Local_Timing_Events
3768 if Restriction_Check_Required (No_Local_Timing_Events)
3769 and then not Is_Library_Level_Entity (Id)
3770 and then Is_RTE (Etype (Id), RE_Timing_Event)
3772 Check_Restriction (No_Local_Timing_Events, N);
3776 if Has_Aspects (N) then
3777 Analyze_Aspect_Specifications (N, Id);
3780 Analyze_Dimension (N);
3781 end Analyze_Object_Declaration;
3783 ---------------------------
3784 -- Analyze_Others_Choice --
3785 ---------------------------
3787 -- Nothing to do for the others choice node itself, the semantic analysis
3788 -- of the others choice will occur as part of the processing of the parent
3790 procedure Analyze_Others_Choice (N : Node_Id) is
3791 pragma Warnings (Off, N);
3794 end Analyze_Others_Choice;
3796 -------------------------------------------
3797 -- Analyze_Private_Extension_Declaration --
3798 -------------------------------------------
3800 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
3801 T : constant Entity_Id := Defining_Identifier (N);
3802 Indic : constant Node_Id := Subtype_Indication (N);
3803 Parent_Type : Entity_Id;
3804 Parent_Base : Entity_Id;
3807 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
3809 if Is_Non_Empty_List (Interface_List (N)) then
3815 Intf := First (Interface_List (N));
3816 while Present (Intf) loop
3817 T := Find_Type_Of_Subtype_Indic (Intf);
3819 Diagnose_Interface (Intf, T);
3825 Generate_Definition (T);
3827 -- For other than Ada 2012, just enter the name in the current scope
3829 if Ada_Version < Ada_2012 then
3832 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
3833 -- case of private type that completes an incomplete type.
3840 Prev := Find_Type_Name (N);
3842 pragma Assert (Prev = T
3843 or else (Ekind (Prev) = E_Incomplete_Type
3844 and then Present (Full_View (Prev))
3845 and then Full_View (Prev) = T));
3849 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
3850 Parent_Base := Base_Type (Parent_Type);
3852 if Parent_Type = Any_Type
3853 or else Etype (Parent_Type) = Any_Type
3855 Set_Ekind (T, Ekind (Parent_Type));
3856 Set_Etype (T, Any_Type);
3859 elsif not Is_Tagged_Type (Parent_Type) then
3861 ("parent of type extension must be a tagged type ", Indic);
3864 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
3865 Error_Msg_N ("premature derivation of incomplete type", Indic);
3868 elsif Is_Concurrent_Type (Parent_Type) then
3870 ("parent type of a private extension cannot be "
3871 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
3873 Set_Etype (T, Any_Type);
3874 Set_Ekind (T, E_Limited_Private_Type);
3875 Set_Private_Dependents (T, New_Elmt_List);
3876 Set_Error_Posted (T);
3880 -- Perhaps the parent type should be changed to the class-wide type's
3881 -- specific type in this case to prevent cascading errors ???
3883 if Is_Class_Wide_Type (Parent_Type) then
3885 ("parent of type extension must not be a class-wide type", Indic);
3889 if (not Is_Package_Or_Generic_Package (Current_Scope)
3890 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
3891 or else In_Private_Part (Current_Scope)
3894 Error_Msg_N ("invalid context for private extension", N);
3897 -- Set common attributes
3899 Set_Is_Pure (T, Is_Pure (Current_Scope));
3900 Set_Scope (T, Current_Scope);
3901 Set_Ekind (T, E_Record_Type_With_Private);
3902 Init_Size_Align (T);
3904 Set_Etype (T, Parent_Base);
3905 Set_Has_Task (T, Has_Task (Parent_Base));
3907 Set_Convention (T, Convention (Parent_Type));
3908 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
3909 Set_Is_First_Subtype (T);
3910 Make_Class_Wide_Type (T);
3912 if Unknown_Discriminants_Present (N) then
3913 Set_Discriminant_Constraint (T, No_Elist);
3916 Build_Derived_Record_Type (N, Parent_Type, T);
3918 -- Propagate inherited invariant information. The new type has
3919 -- invariants, if the parent type has inheritable invariants,
3920 -- and these invariants can in turn be inherited.
3922 if Has_Inheritable_Invariants (Parent_Type) then
3923 Set_Has_Inheritable_Invariants (T);
3924 Set_Has_Invariants (T);
3927 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
3928 -- synchronized formal derived type.
3930 if Ada_Version >= Ada_2005
3931 and then Synchronized_Present (N)
3933 Set_Is_Limited_Record (T);
3935 -- Formal derived type case
3937 if Is_Generic_Type (T) then
3939 -- The parent must be a tagged limited type or a synchronized
3942 if (not Is_Tagged_Type (Parent_Type)
3943 or else not Is_Limited_Type (Parent_Type))
3945 (not Is_Interface (Parent_Type)
3946 or else not Is_Synchronized_Interface (Parent_Type))
3948 Error_Msg_NE ("parent type of & must be tagged limited " &
3949 "or synchronized", N, T);
3952 -- The progenitors (if any) must be limited or synchronized
3955 if Present (Interfaces (T)) then
3958 Iface_Elmt : Elmt_Id;
3961 Iface_Elmt := First_Elmt (Interfaces (T));
3962 while Present (Iface_Elmt) loop
3963 Iface := Node (Iface_Elmt);
3965 if not Is_Limited_Interface (Iface)
3966 and then not Is_Synchronized_Interface (Iface)
3968 Error_Msg_NE ("progenitor & must be limited " &
3969 "or synchronized", N, Iface);
3972 Next_Elmt (Iface_Elmt);
3977 -- Regular derived extension, the parent must be a limited or
3978 -- synchronized interface.
3981 if not Is_Interface (Parent_Type)
3982 or else (not Is_Limited_Interface (Parent_Type)
3984 not Is_Synchronized_Interface (Parent_Type))
3987 ("parent type of & must be limited interface", N, T);
3991 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
3992 -- extension with a synchronized parent must be explicitly declared
3993 -- synchronized, because the full view will be a synchronized type.
3994 -- This must be checked before the check for limited types below,
3995 -- to ensure that types declared limited are not allowed to extend
3996 -- synchronized interfaces.
3998 elsif Is_Interface (Parent_Type)
3999 and then Is_Synchronized_Interface (Parent_Type)
4000 and then not Synchronized_Present (N)
4003 ("private extension of& must be explicitly synchronized",
4006 elsif Limited_Present (N) then
4007 Set_Is_Limited_Record (T);
4009 if not Is_Limited_Type (Parent_Type)
4011 (not Is_Interface (Parent_Type)
4012 or else not Is_Limited_Interface (Parent_Type))
4014 Error_Msg_NE ("parent type& of limited extension must be limited",
4020 if Has_Aspects (N) then
4021 Analyze_Aspect_Specifications (N, T);
4023 end Analyze_Private_Extension_Declaration;
4025 ---------------------------------
4026 -- Analyze_Subtype_Declaration --
4027 ---------------------------------
4029 procedure Analyze_Subtype_Declaration
4031 Skip : Boolean := False)
4033 Id : constant Entity_Id := Defining_Identifier (N);
4035 R_Checks : Check_Result;
4038 Generate_Definition (Id);
4039 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4040 Init_Size_Align (Id);
4042 -- The following guard condition on Enter_Name is to handle cases where
4043 -- the defining identifier has already been entered into the scope but
4044 -- the declaration as a whole needs to be analyzed.
4046 -- This case in particular happens for derived enumeration types. The
4047 -- derived enumeration type is processed as an inserted enumeration type
4048 -- declaration followed by a rewritten subtype declaration. The defining
4049 -- identifier, however, is entered into the name scope very early in the
4050 -- processing of the original type declaration and therefore needs to be
4051 -- avoided here, when the created subtype declaration is analyzed. (See
4052 -- Build_Derived_Types)
4054 -- This also happens when the full view of a private type is derived
4055 -- type with constraints. In this case the entity has been introduced
4056 -- in the private declaration.
4059 or else (Present (Etype (Id))
4060 and then (Is_Private_Type (Etype (Id))
4061 or else Is_Task_Type (Etype (Id))
4062 or else Is_Rewrite_Substitution (N)))
4070 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4072 -- Class-wide equivalent types of records with unknown discriminants
4073 -- involve the generation of an itype which serves as the private view
4074 -- of a constrained record subtype. In such cases the base type of the
4075 -- current subtype we are processing is the private itype. Use the full
4076 -- of the private itype when decorating various attributes.
4079 and then Is_Private_Type (T)
4080 and then Present (Full_View (T))
4085 -- Inherit common attributes
4087 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4088 Set_Is_Volatile (Id, Is_Volatile (T));
4089 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4090 Set_Is_Atomic (Id, Is_Atomic (T));
4091 Set_Is_Ada_2005_Only (Id, Is_Ada_2005_Only (T));
4092 Set_Is_Ada_2012_Only (Id, Is_Ada_2012_Only (T));
4093 Set_Convention (Id, Convention (T));
4095 -- If ancestor has predicates then so does the subtype, and in addition
4096 -- we must delay the freeze to properly arrange predicate inheritance.
4098 -- The Ancestor_Type test is a big kludge, there seem to be cases in
4099 -- which T = ID, so the above tests and assignments do nothing???
4101 if Has_Predicates (T)
4102 or else (Present (Ancestor_Subtype (T))
4103 and then Has_Predicates (Ancestor_Subtype (T)))
4105 Set_Has_Predicates (Id);
4106 Set_Has_Delayed_Freeze (Id);
4109 -- Subtype of Boolean cannot have a constraint in SPARK
4111 if Is_Boolean_Type (T)
4112 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4114 Check_SPARK_Restriction
4115 ("subtype of Boolean cannot have constraint", N);
4118 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4120 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4126 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4127 One_Cstr := First (Constraints (Cstr));
4128 while Present (One_Cstr) loop
4130 -- Index or discriminant constraint in SPARK must be a
4134 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4136 Check_SPARK_Restriction
4137 ("subtype mark required", One_Cstr);
4139 -- String subtype must have a lower bound of 1 in SPARK.
4140 -- Note that we do not need to test for the non-static case
4141 -- here, since that was already taken care of in
4142 -- Process_Range_Expr_In_Decl.
4144 elsif Base_Type (T) = Standard_String then
4145 Get_Index_Bounds (One_Cstr, Low, High);
4147 if Is_OK_Static_Expression (Low)
4148 and then Expr_Value (Low) /= 1
4150 Check_SPARK_Restriction
4151 ("String subtype must have lower bound of 1", N);
4161 -- In the case where there is no constraint given in the subtype
4162 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4163 -- semantic attributes must be established here.
4165 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
4166 Set_Etype (Id, Base_Type (T));
4168 -- Subtype of unconstrained array without constraint is not allowed
4171 if Is_Array_Type (T)
4172 and then not Is_Constrained (T)
4174 Check_SPARK_Restriction
4175 ("subtype of unconstrained array must have constraint", N);
4180 Set_Ekind (Id, E_Array_Subtype);
4181 Copy_Array_Subtype_Attributes (Id, T);
4183 when Decimal_Fixed_Point_Kind =>
4184 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
4185 Set_Digits_Value (Id, Digits_Value (T));
4186 Set_Delta_Value (Id, Delta_Value (T));
4187 Set_Scale_Value (Id, Scale_Value (T));
4188 Set_Small_Value (Id, Small_Value (T));
4189 Set_Scalar_Range (Id, Scalar_Range (T));
4190 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
4191 Set_Is_Constrained (Id, Is_Constrained (T));
4192 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4193 Set_RM_Size (Id, RM_Size (T));
4195 when Enumeration_Kind =>
4196 Set_Ekind (Id, E_Enumeration_Subtype);
4197 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4198 Set_Scalar_Range (Id, Scalar_Range (T));
4199 Set_Is_Character_Type (Id, Is_Character_Type (T));
4200 Set_Is_Constrained (Id, Is_Constrained (T));
4201 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4202 Set_RM_Size (Id, RM_Size (T));
4204 when Ordinary_Fixed_Point_Kind =>
4205 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4206 Set_Scalar_Range (Id, Scalar_Range (T));
4207 Set_Small_Value (Id, Small_Value (T));
4208 Set_Delta_Value (Id, Delta_Value (T));
4209 Set_Is_Constrained (Id, Is_Constrained (T));
4210 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4211 Set_RM_Size (Id, RM_Size (T));
4214 Set_Ekind (Id, E_Floating_Point_Subtype);
4215 Set_Scalar_Range (Id, Scalar_Range (T));
4216 Set_Digits_Value (Id, Digits_Value (T));
4217 Set_Is_Constrained (Id, Is_Constrained (T));
4219 when Signed_Integer_Kind =>
4220 Set_Ekind (Id, E_Signed_Integer_Subtype);
4221 Set_Scalar_Range (Id, Scalar_Range (T));
4222 Set_Is_Constrained (Id, Is_Constrained (T));
4223 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4224 Set_RM_Size (Id, RM_Size (T));
4226 when Modular_Integer_Kind =>
4227 Set_Ekind (Id, E_Modular_Integer_Subtype);
4228 Set_Scalar_Range (Id, Scalar_Range (T));
4229 Set_Is_Constrained (Id, Is_Constrained (T));
4230 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4231 Set_RM_Size (Id, RM_Size (T));
4233 when Class_Wide_Kind =>
4234 Set_Ekind (Id, E_Class_Wide_Subtype);
4235 Set_First_Entity (Id, First_Entity (T));
4236 Set_Last_Entity (Id, Last_Entity (T));
4237 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4238 Set_Cloned_Subtype (Id, T);
4239 Set_Is_Tagged_Type (Id, True);
4240 Set_Has_Unknown_Discriminants
4243 if Ekind (T) = E_Class_Wide_Subtype then
4244 Set_Equivalent_Type (Id, Equivalent_Type (T));
4247 when E_Record_Type | E_Record_Subtype =>
4248 Set_Ekind (Id, E_Record_Subtype);
4250 if Ekind (T) = E_Record_Subtype
4251 and then Present (Cloned_Subtype (T))
4253 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
4255 Set_Cloned_Subtype (Id, T);
4258 Set_First_Entity (Id, First_Entity (T));
4259 Set_Last_Entity (Id, Last_Entity (T));
4260 Set_Has_Discriminants (Id, Has_Discriminants (T));
4261 Set_Is_Constrained (Id, Is_Constrained (T));
4262 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4263 Set_Has_Implicit_Dereference
4264 (Id, Has_Implicit_Dereference (T));
4265 Set_Has_Unknown_Discriminants
4266 (Id, Has_Unknown_Discriminants (T));
4268 if Has_Discriminants (T) then
4269 Set_Discriminant_Constraint
4270 (Id, Discriminant_Constraint (T));
4271 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4273 elsif Has_Unknown_Discriminants (Id) then
4274 Set_Discriminant_Constraint (Id, No_Elist);
4277 if Is_Tagged_Type (T) then
4278 Set_Is_Tagged_Type (Id);
4279 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4280 Set_Direct_Primitive_Operations
4281 (Id, Direct_Primitive_Operations (T));
4282 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4284 if Is_Interface (T) then
4285 Set_Is_Interface (Id);
4286 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
4290 when Private_Kind =>
4291 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4292 Set_Has_Discriminants (Id, Has_Discriminants (T));
4293 Set_Is_Constrained (Id, Is_Constrained (T));
4294 Set_First_Entity (Id, First_Entity (T));
4295 Set_Last_Entity (Id, Last_Entity (T));
4296 Set_Private_Dependents (Id, New_Elmt_List);
4297 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4298 Set_Has_Implicit_Dereference
4299 (Id, Has_Implicit_Dereference (T));
4300 Set_Has_Unknown_Discriminants
4301 (Id, Has_Unknown_Discriminants (T));
4302 Set_Known_To_Have_Preelab_Init
4303 (Id, Known_To_Have_Preelab_Init (T));
4305 if Is_Tagged_Type (T) then
4306 Set_Is_Tagged_Type (Id);
4307 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4308 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4309 Set_Direct_Primitive_Operations (Id,
4310 Direct_Primitive_Operations (T));
4313 -- In general the attributes of the subtype of a private type
4314 -- are the attributes of the partial view of parent. However,
4315 -- the full view may be a discriminated type, and the subtype
4316 -- must share the discriminant constraint to generate correct
4317 -- calls to initialization procedures.
4319 if Has_Discriminants (T) then
4320 Set_Discriminant_Constraint
4321 (Id, Discriminant_Constraint (T));
4322 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4324 elsif Present (Full_View (T))
4325 and then Has_Discriminants (Full_View (T))
4327 Set_Discriminant_Constraint
4328 (Id, Discriminant_Constraint (Full_View (T)));
4329 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4331 -- This would seem semantically correct, but apparently
4332 -- confuses the back-end. To be explained and checked with
4333 -- current version ???
4335 -- Set_Has_Discriminants (Id);
4338 Prepare_Private_Subtype_Completion (Id, N);
4341 Set_Ekind (Id, E_Access_Subtype);
4342 Set_Is_Constrained (Id, Is_Constrained (T));
4343 Set_Is_Access_Constant
4344 (Id, Is_Access_Constant (T));
4345 Set_Directly_Designated_Type
4346 (Id, Designated_Type (T));
4347 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
4349 -- A Pure library_item must not contain the declaration of a
4350 -- named access type, except within a subprogram, generic
4351 -- subprogram, task unit, or protected unit, or if it has
4352 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
4354 if Comes_From_Source (Id)
4355 and then In_Pure_Unit
4356 and then not In_Subprogram_Task_Protected_Unit
4357 and then not No_Pool_Assigned (Id)
4360 ("named access types not allowed in pure unit", N);
4363 when Concurrent_Kind =>
4364 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4365 Set_Corresponding_Record_Type (Id,
4366 Corresponding_Record_Type (T));
4367 Set_First_Entity (Id, First_Entity (T));
4368 Set_First_Private_Entity (Id, First_Private_Entity (T));
4369 Set_Has_Discriminants (Id, Has_Discriminants (T));
4370 Set_Is_Constrained (Id, Is_Constrained (T));
4371 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4372 Set_Last_Entity (Id, Last_Entity (T));
4374 if Has_Discriminants (T) then
4375 Set_Discriminant_Constraint (Id,
4376 Discriminant_Constraint (T));
4377 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4380 when E_Incomplete_Type =>
4381 if Ada_Version >= Ada_2005 then
4382 Set_Ekind (Id, E_Incomplete_Subtype);
4384 -- Ada 2005 (AI-412): Decorate an incomplete subtype
4385 -- of an incomplete type visible through a limited
4388 if From_With_Type (T)
4389 and then Present (Non_Limited_View (T))
4391 Set_From_With_Type (Id);
4392 Set_Non_Limited_View (Id, Non_Limited_View (T));
4394 -- Ada 2005 (AI-412): Add the regular incomplete subtype
4395 -- to the private dependents of the original incomplete
4396 -- type for future transformation.
4399 Append_Elmt (Id, Private_Dependents (T));
4402 -- If the subtype name denotes an incomplete type an error
4403 -- was already reported by Process_Subtype.
4406 Set_Etype (Id, Any_Type);
4410 raise Program_Error;
4414 if Etype (Id) = Any_Type then
4418 -- Some common processing on all types
4420 Set_Size_Info (Id, T);
4421 Set_First_Rep_Item (Id, First_Rep_Item (T));
4425 Set_Is_Immediately_Visible (Id, True);
4426 Set_Depends_On_Private (Id, Has_Private_Component (T));
4427 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
4429 if Is_Interface (T) then
4430 Set_Is_Interface (Id);
4433 if Present (Generic_Parent_Type (N))
4436 (Parent (Generic_Parent_Type (N))) /= N_Formal_Type_Declaration
4438 (Formal_Type_Definition (Parent (Generic_Parent_Type (N))))
4439 /= N_Formal_Private_Type_Definition)
4441 if Is_Tagged_Type (Id) then
4443 -- If this is a generic actual subtype for a synchronized type,
4444 -- the primitive operations are those of the corresponding record
4445 -- for which there is a separate subtype declaration.
4447 if Is_Concurrent_Type (Id) then
4449 elsif Is_Class_Wide_Type (Id) then
4450 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
4452 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
4455 elsif Scope (Etype (Id)) /= Standard_Standard then
4456 Derive_Subprograms (Generic_Parent_Type (N), Id);
4460 if Is_Private_Type (T)
4461 and then Present (Full_View (T))
4463 Conditional_Delay (Id, Full_View (T));
4465 -- The subtypes of components or subcomponents of protected types
4466 -- do not need freeze nodes, which would otherwise appear in the
4467 -- wrong scope (before the freeze node for the protected type). The
4468 -- proper subtypes are those of the subcomponents of the corresponding
4471 elsif Ekind (Scope (Id)) /= E_Protected_Type
4472 and then Present (Scope (Scope (Id))) -- error defense!
4473 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
4475 Conditional_Delay (Id, T);
4478 -- Check that Constraint_Error is raised for a scalar subtype indication
4479 -- when the lower or upper bound of a non-null range lies outside the
4480 -- range of the type mark.
4482 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4483 if Is_Scalar_Type (Etype (Id))
4484 and then Scalar_Range (Id) /=
4485 Scalar_Range (Etype (Subtype_Mark
4486 (Subtype_Indication (N))))
4490 Etype (Subtype_Mark (Subtype_Indication (N))));
4492 -- In the array case, check compatibility for each index
4494 elsif Is_Array_Type (Etype (Id))
4495 and then Present (First_Index (Id))
4497 -- This really should be a subprogram that finds the indications
4501 Subt_Index : Node_Id := First_Index (Id);
4502 Target_Index : Node_Id :=
4504 (Subtype_Mark (Subtype_Indication (N))));
4505 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
4508 while Present (Subt_Index) loop
4509 if ((Nkind (Subt_Index) = N_Identifier
4510 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
4511 or else Nkind (Subt_Index) = N_Subtype_Indication)
4513 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
4516 Target_Typ : constant Entity_Id :=
4517 Etype (Target_Index);
4521 (Scalar_Range (Etype (Subt_Index)),
4524 Defining_Identifier (N));
4526 -- Reset Has_Dynamic_Range_Check on the subtype to
4527 -- prevent elision of the index check due to a dynamic
4528 -- check generated for a preceding index (needed since
4529 -- Insert_Range_Checks tries to avoid generating
4530 -- redundant checks on a given declaration).
4532 Set_Has_Dynamic_Range_Check (N, False);
4538 Sloc (Defining_Identifier (N)));
4540 -- Record whether this index involved a dynamic check
4543 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
4547 Next_Index (Subt_Index);
4548 Next_Index (Target_Index);
4551 -- Finally, mark whether the subtype involves dynamic checks
4553 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
4558 -- Make sure that generic actual types are properly frozen. The subtype
4559 -- is marked as a generic actual type when the enclosing instance is
4560 -- analyzed, so here we identify the subtype from the tree structure.
4563 and then Is_Generic_Actual_Type (Id)
4564 and then In_Instance
4565 and then not Comes_From_Source (N)
4566 and then Nkind (Subtype_Indication (N)) /= N_Subtype_Indication
4567 and then Is_Frozen (T)
4569 Freeze_Before (N, Id);
4572 Set_Optimize_Alignment_Flags (Id);
4573 Check_Eliminated (Id);
4576 if Has_Aspects (N) then
4577 Analyze_Aspect_Specifications (N, Id);
4580 Analyze_Dimension (N);
4581 end Analyze_Subtype_Declaration;
4583 --------------------------------
4584 -- Analyze_Subtype_Indication --
4585 --------------------------------
4587 procedure Analyze_Subtype_Indication (N : Node_Id) is
4588 T : constant Entity_Id := Subtype_Mark (N);
4589 R : constant Node_Id := Range_Expression (Constraint (N));
4596 Set_Etype (N, Etype (R));
4597 Resolve (R, Entity (T));
4599 Set_Error_Posted (R);
4600 Set_Error_Posted (T);
4602 end Analyze_Subtype_Indication;
4604 --------------------------
4605 -- Analyze_Variant_Part --
4606 --------------------------
4608 procedure Analyze_Variant_Part (N : Node_Id) is
4610 procedure Non_Static_Choice_Error (Choice : Node_Id);
4611 -- Error routine invoked by the generic instantiation below when the
4612 -- variant part has a non static choice.
4614 procedure Process_Declarations (Variant : Node_Id);
4615 -- Analyzes all the declarations associated with a Variant. Needed by
4616 -- the generic instantiation below.
4618 package Variant_Choices_Processing is new
4619 Generic_Choices_Processing
4620 (Get_Alternatives => Variants,
4621 Get_Choices => Discrete_Choices,
4622 Process_Empty_Choice => No_OP,
4623 Process_Non_Static_Choice => Non_Static_Choice_Error,
4624 Process_Associated_Node => Process_Declarations);
4625 use Variant_Choices_Processing;
4626 -- Instantiation of the generic choice processing package
4628 -----------------------------
4629 -- Non_Static_Choice_Error --
4630 -----------------------------
4632 procedure Non_Static_Choice_Error (Choice : Node_Id) is
4634 Flag_Non_Static_Expr
4635 ("choice given in variant part is not static!", Choice);
4636 end Non_Static_Choice_Error;
4638 --------------------------
4639 -- Process_Declarations --
4640 --------------------------
4642 procedure Process_Declarations (Variant : Node_Id) is
4644 if not Null_Present (Component_List (Variant)) then
4645 Analyze_Declarations (Component_Items (Component_List (Variant)));
4647 if Present (Variant_Part (Component_List (Variant))) then
4648 Analyze (Variant_Part (Component_List (Variant)));
4651 end Process_Declarations;
4655 Discr_Name : Node_Id;
4656 Discr_Type : Entity_Id;
4658 Dont_Care : Boolean;
4659 Others_Present : Boolean := False;
4661 pragma Warnings (Off, Dont_Care);
4662 pragma Warnings (Off, Others_Present);
4663 -- We don't care about the assigned values of any of these
4665 -- Start of processing for Analyze_Variant_Part
4668 Discr_Name := Name (N);
4669 Analyze (Discr_Name);
4671 -- If Discr_Name bad, get out (prevent cascaded errors)
4673 if Etype (Discr_Name) = Any_Type then
4677 -- Check invalid discriminant in variant part
4679 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
4680 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
4683 Discr_Type := Etype (Entity (Discr_Name));
4685 if not Is_Discrete_Type (Discr_Type) then
4687 ("discriminant in a variant part must be of a discrete type",
4692 -- Call the instantiated Analyze_Choices which does the rest of the work
4694 Analyze_Choices (N, Discr_Type, Dont_Care, Others_Present);
4695 end Analyze_Variant_Part;
4697 ----------------------------
4698 -- Array_Type_Declaration --
4699 ----------------------------
4701 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
4702 Component_Def : constant Node_Id := Component_Definition (Def);
4703 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
4704 Element_Type : Entity_Id;
4705 Implicit_Base : Entity_Id;
4707 Related_Id : Entity_Id := Empty;
4709 P : constant Node_Id := Parent (Def);
4713 if Nkind (Def) = N_Constrained_Array_Definition then
4714 Index := First (Discrete_Subtype_Definitions (Def));
4716 Index := First (Subtype_Marks (Def));
4719 -- Find proper names for the implicit types which may be public. In case
4720 -- of anonymous arrays we use the name of the first object of that type
4724 Related_Id := Defining_Identifier (P);
4730 while Present (Index) loop
4733 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
4734 Check_SPARK_Restriction ("subtype mark required", Index);
4737 -- Add a subtype declaration for each index of private array type
4738 -- declaration whose etype is also private. For example:
4741 -- type Index is private;
4743 -- type Table is array (Index) of ...
4746 -- This is currently required by the expander for the internally
4747 -- generated equality subprogram of records with variant parts in
4748 -- which the etype of some component is such private type.
4750 if Ekind (Current_Scope) = E_Package
4751 and then In_Private_Part (Current_Scope)
4752 and then Has_Private_Declaration (Etype (Index))
4755 Loc : constant Source_Ptr := Sloc (Def);
4760 New_E := Make_Temporary (Loc, 'T');
4761 Set_Is_Internal (New_E);
4764 Make_Subtype_Declaration (Loc,
4765 Defining_Identifier => New_E,
4766 Subtype_Indication =>
4767 New_Occurrence_Of (Etype (Index), Loc));
4769 Insert_Before (Parent (Def), Decl);
4771 Set_Etype (Index, New_E);
4773 -- If the index is a range the Entity attribute is not
4774 -- available. Example:
4777 -- type T is private;
4779 -- type T is new Natural;
4780 -- Table : array (T(1) .. T(10)) of Boolean;
4783 if Nkind (Index) /= N_Range then
4784 Set_Entity (Index, New_E);
4789 Make_Index (Index, P, Related_Id, Nb_Index);
4791 -- Check error of subtype with predicate for index type
4793 Bad_Predicated_Subtype_Use
4794 ("subtype& has predicate, not allowed as index subtype",
4795 Index, Etype (Index));
4797 -- Move to next index
4800 Nb_Index := Nb_Index + 1;
4803 -- Process subtype indication if one is present
4805 if Present (Component_Typ) then
4806 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
4808 Set_Etype (Component_Typ, Element_Type);
4810 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
4811 Check_SPARK_Restriction ("subtype mark required", Component_Typ);
4814 -- Ada 2005 (AI-230): Access Definition case
4816 else pragma Assert (Present (Access_Definition (Component_Def)));
4818 -- Indicate that the anonymous access type is created by the
4819 -- array type declaration.
4821 Element_Type := Access_Definition
4823 N => Access_Definition (Component_Def));
4824 Set_Is_Local_Anonymous_Access (Element_Type);
4826 -- Propagate the parent. This field is needed if we have to generate
4827 -- the master_id associated with an anonymous access to task type
4828 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
4830 Set_Parent (Element_Type, Parent (T));
4832 -- Ada 2005 (AI-230): In case of components that are anonymous access
4833 -- types the level of accessibility depends on the enclosing type
4836 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
4838 -- Ada 2005 (AI-254)
4841 CD : constant Node_Id :=
4842 Access_To_Subprogram_Definition
4843 (Access_Definition (Component_Def));
4845 if Present (CD) and then Protected_Present (CD) then
4847 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
4852 -- Constrained array case
4855 T := Create_Itype (E_Void, P, Related_Id, 'T');
4858 if Nkind (Def) = N_Constrained_Array_Definition then
4860 -- Establish Implicit_Base as unconstrained base type
4862 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
4864 Set_Etype (Implicit_Base, Implicit_Base);
4865 Set_Scope (Implicit_Base, Current_Scope);
4866 Set_Has_Delayed_Freeze (Implicit_Base);
4868 -- The constrained array type is a subtype of the unconstrained one
4870 Set_Ekind (T, E_Array_Subtype);
4871 Init_Size_Align (T);
4872 Set_Etype (T, Implicit_Base);
4873 Set_Scope (T, Current_Scope);
4874 Set_Is_Constrained (T, True);
4875 Set_First_Index (T, First (Discrete_Subtype_Definitions (Def)));
4876 Set_Has_Delayed_Freeze (T);
4878 -- Complete setup of implicit base type
4880 Set_First_Index (Implicit_Base, First_Index (T));
4881 Set_Component_Type (Implicit_Base, Element_Type);
4882 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
4883 Set_Component_Size (Implicit_Base, Uint_0);
4884 Set_Packed_Array_Type (Implicit_Base, Empty);
4885 Set_Has_Controlled_Component
4886 (Implicit_Base, Has_Controlled_Component
4888 or else Is_Controlled
4890 Set_Finalize_Storage_Only
4891 (Implicit_Base, Finalize_Storage_Only
4894 -- Unconstrained array case
4897 Set_Ekind (T, E_Array_Type);
4898 Init_Size_Align (T);
4900 Set_Scope (T, Current_Scope);
4901 Set_Component_Size (T, Uint_0);
4902 Set_Is_Constrained (T, False);
4903 Set_First_Index (T, First (Subtype_Marks (Def)));
4904 Set_Has_Delayed_Freeze (T, True);
4905 Set_Has_Task (T, Has_Task (Element_Type));
4906 Set_Has_Controlled_Component (T, Has_Controlled_Component
4909 Is_Controlled (Element_Type));
4910 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
4914 -- Common attributes for both cases
4916 Set_Component_Type (Base_Type (T), Element_Type);
4917 Set_Packed_Array_Type (T, Empty);
4919 if Aliased_Present (Component_Definition (Def)) then
4920 Check_SPARK_Restriction
4921 ("aliased is not allowed", Component_Definition (Def));
4922 Set_Has_Aliased_Components (Etype (T));
4925 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
4926 -- array type to ensure that objects of this type are initialized.
4928 if Ada_Version >= Ada_2005
4929 and then Can_Never_Be_Null (Element_Type)
4931 Set_Can_Never_Be_Null (T);
4933 if Null_Exclusion_Present (Component_Definition (Def))
4935 -- No need to check itypes because in their case this check was
4936 -- done at their point of creation
4938 and then not Is_Itype (Element_Type)
4941 ("`NOT NULL` not allowed (null already excluded)",
4942 Subtype_Indication (Component_Definition (Def)));
4946 Priv := Private_Component (Element_Type);
4948 if Present (Priv) then
4950 -- Check for circular definitions
4952 if Priv = Any_Type then
4953 Set_Component_Type (Etype (T), Any_Type);
4955 -- There is a gap in the visibility of operations on the composite
4956 -- type only if the component type is defined in a different scope.
4958 elsif Scope (Priv) = Current_Scope then
4961 elsif Is_Limited_Type (Priv) then
4962 Set_Is_Limited_Composite (Etype (T));
4963 Set_Is_Limited_Composite (T);
4965 Set_Is_Private_Composite (Etype (T));
4966 Set_Is_Private_Composite (T);
4970 -- A syntax error in the declaration itself may lead to an empty index
4971 -- list, in which case do a minimal patch.
4973 if No (First_Index (T)) then
4974 Error_Msg_N ("missing index definition in array type declaration", T);
4977 Indexes : constant List_Id :=
4978 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
4980 Set_Discrete_Subtype_Definitions (Def, Indexes);
4981 Set_First_Index (T, First (Indexes));
4986 -- Create a concatenation operator for the new type. Internal array
4987 -- types created for packed entities do not need such, they are
4988 -- compatible with the user-defined type.
4990 if Number_Dimensions (T) = 1
4991 and then not Is_Packed_Array_Type (T)
4993 New_Concatenation_Op (T);
4996 -- In the case of an unconstrained array the parser has already verified
4997 -- that all the indexes are unconstrained but we still need to make sure
4998 -- that the element type is constrained.
5000 if Is_Indefinite_Subtype (Element_Type) then
5002 ("unconstrained element type in array declaration",
5003 Subtype_Indication (Component_Def));
5005 elsif Is_Abstract_Type (Element_Type) then
5007 ("the type of a component cannot be abstract",
5008 Subtype_Indication (Component_Def));
5010 end Array_Type_Declaration;
5012 ------------------------------------------------------
5013 -- Replace_Anonymous_Access_To_Protected_Subprogram --
5014 ------------------------------------------------------
5016 function Replace_Anonymous_Access_To_Protected_Subprogram
5017 (N : Node_Id) return Entity_Id
5019 Loc : constant Source_Ptr := Sloc (N);
5021 Curr_Scope : constant Scope_Stack_Entry :=
5022 Scope_Stack.Table (Scope_Stack.Last);
5024 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
5031 Set_Is_Internal (Anon);
5034 when N_Component_Declaration |
5035 N_Unconstrained_Array_Definition |
5036 N_Constrained_Array_Definition =>
5037 Comp := Component_Definition (N);
5038 Acc := Access_Definition (Comp);
5040 when N_Discriminant_Specification =>
5041 Comp := Discriminant_Type (N);
5044 when N_Parameter_Specification =>
5045 Comp := Parameter_Type (N);
5048 when N_Access_Function_Definition =>
5049 Comp := Result_Definition (N);
5052 when N_Object_Declaration =>
5053 Comp := Object_Definition (N);
5056 when N_Function_Specification =>
5057 Comp := Result_Definition (N);
5061 raise Program_Error;
5064 Decl := Make_Full_Type_Declaration (Loc,
5065 Defining_Identifier => Anon,
5067 Copy_Separate_Tree (Access_To_Subprogram_Definition (Acc)));
5069 Mark_Rewrite_Insertion (Decl);
5071 -- Insert the new declaration in the nearest enclosing scope. If the
5072 -- node is a body and N is its return type, the declaration belongs in
5073 -- the enclosing scope.
5077 if Nkind (P) = N_Subprogram_Body
5078 and then Nkind (N) = N_Function_Specification
5083 while Present (P) and then not Has_Declarations (P) loop
5087 pragma Assert (Present (P));
5089 if Nkind (P) = N_Package_Specification then
5090 Prepend (Decl, Visible_Declarations (P));
5092 Prepend (Decl, Declarations (P));
5095 -- Replace the anonymous type with an occurrence of the new declaration.
5096 -- In all cases the rewritten node does not have the null-exclusion
5097 -- attribute because (if present) it was already inherited by the
5098 -- anonymous entity (Anon). Thus, in case of components we do not
5099 -- inherit this attribute.
5101 if Nkind (N) = N_Parameter_Specification then
5102 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5103 Set_Etype (Defining_Identifier (N), Anon);
5104 Set_Null_Exclusion_Present (N, False);
5106 elsif Nkind (N) = N_Object_Declaration then
5107 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5108 Set_Etype (Defining_Identifier (N), Anon);
5110 elsif Nkind (N) = N_Access_Function_Definition then
5111 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5113 elsif Nkind (N) = N_Function_Specification then
5114 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5115 Set_Etype (Defining_Unit_Name (N), Anon);
5119 Make_Component_Definition (Loc,
5120 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
5123 Mark_Rewrite_Insertion (Comp);
5125 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition) then
5129 -- Temporarily remove the current scope (record or subprogram) from
5130 -- the stack to add the new declarations to the enclosing scope.
5132 Scope_Stack.Decrement_Last;
5134 Set_Is_Itype (Anon);
5135 Scope_Stack.Append (Curr_Scope);
5138 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
5139 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
5141 end Replace_Anonymous_Access_To_Protected_Subprogram;
5143 -------------------------------
5144 -- Build_Derived_Access_Type --
5145 -------------------------------
5147 procedure Build_Derived_Access_Type
5149 Parent_Type : Entity_Id;
5150 Derived_Type : Entity_Id)
5152 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
5154 Desig_Type : Entity_Id;
5156 Discr_Con_Elist : Elist_Id;
5157 Discr_Con_El : Elmt_Id;
5161 -- Set the designated type so it is available in case this is an access
5162 -- to a self-referential type, e.g. a standard list type with a next
5163 -- pointer. Will be reset after subtype is built.
5165 Set_Directly_Designated_Type
5166 (Derived_Type, Designated_Type (Parent_Type));
5168 Subt := Process_Subtype (S, N);
5170 if Nkind (S) /= N_Subtype_Indication
5171 and then Subt /= Base_Type (Subt)
5173 Set_Ekind (Derived_Type, E_Access_Subtype);
5176 if Ekind (Derived_Type) = E_Access_Subtype then
5178 Pbase : constant Entity_Id := Base_Type (Parent_Type);
5179 Ibase : constant Entity_Id :=
5180 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
5181 Svg_Chars : constant Name_Id := Chars (Ibase);
5182 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
5185 Copy_Node (Pbase, Ibase);
5187 Set_Chars (Ibase, Svg_Chars);
5188 Set_Next_Entity (Ibase, Svg_Next_E);
5189 Set_Sloc (Ibase, Sloc (Derived_Type));
5190 Set_Scope (Ibase, Scope (Derived_Type));
5191 Set_Freeze_Node (Ibase, Empty);
5192 Set_Is_Frozen (Ibase, False);
5193 Set_Comes_From_Source (Ibase, False);
5194 Set_Is_First_Subtype (Ibase, False);
5196 Set_Etype (Ibase, Pbase);
5197 Set_Etype (Derived_Type, Ibase);
5201 Set_Directly_Designated_Type
5202 (Derived_Type, Designated_Type (Subt));
5204 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
5205 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
5206 Set_Size_Info (Derived_Type, Parent_Type);
5207 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
5208 Set_Depends_On_Private (Derived_Type,
5209 Has_Private_Component (Derived_Type));
5210 Conditional_Delay (Derived_Type, Subt);
5212 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
5213 -- that it is not redundant.
5215 if Null_Exclusion_Present (Type_Definition (N)) then
5216 Set_Can_Never_Be_Null (Derived_Type);
5218 if Can_Never_Be_Null (Parent_Type)
5222 ("`NOT NULL` not allowed (& already excludes null)",
5226 elsif Can_Never_Be_Null (Parent_Type) then
5227 Set_Can_Never_Be_Null (Derived_Type);
5230 -- Note: we do not copy the Storage_Size_Variable, since we always go to
5231 -- the root type for this information.
5233 -- Apply range checks to discriminants for derived record case
5234 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
5236 Desig_Type := Designated_Type (Derived_Type);
5237 if Is_Composite_Type (Desig_Type)
5238 and then (not Is_Array_Type (Desig_Type))
5239 and then Has_Discriminants (Desig_Type)
5240 and then Base_Type (Desig_Type) /= Desig_Type
5242 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
5243 Discr_Con_El := First_Elmt (Discr_Con_Elist);
5245 Discr := First_Discriminant (Base_Type (Desig_Type));
5246 while Present (Discr_Con_El) loop
5247 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
5248 Next_Elmt (Discr_Con_El);
5249 Next_Discriminant (Discr);
5252 end Build_Derived_Access_Type;
5254 ------------------------------
5255 -- Build_Derived_Array_Type --
5256 ------------------------------
5258 procedure Build_Derived_Array_Type
5260 Parent_Type : Entity_Id;
5261 Derived_Type : Entity_Id)
5263 Loc : constant Source_Ptr := Sloc (N);
5264 Tdef : constant Node_Id := Type_Definition (N);
5265 Indic : constant Node_Id := Subtype_Indication (Tdef);
5266 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5267 Implicit_Base : Entity_Id;
5268 New_Indic : Node_Id;
5270 procedure Make_Implicit_Base;
5271 -- If the parent subtype is constrained, the derived type is a subtype
5272 -- of an implicit base type derived from the parent base.
5274 ------------------------
5275 -- Make_Implicit_Base --
5276 ------------------------
5278 procedure Make_Implicit_Base is
5281 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5283 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5284 Set_Etype (Implicit_Base, Parent_Base);
5286 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
5287 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
5289 Set_Has_Delayed_Freeze (Implicit_Base, True);
5290 end Make_Implicit_Base;
5292 -- Start of processing for Build_Derived_Array_Type
5295 if not Is_Constrained (Parent_Type) then
5296 if Nkind (Indic) /= N_Subtype_Indication then
5297 Set_Ekind (Derived_Type, E_Array_Type);
5299 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5300 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
5302 Set_Has_Delayed_Freeze (Derived_Type, True);
5306 Set_Etype (Derived_Type, Implicit_Base);
5309 Make_Subtype_Declaration (Loc,
5310 Defining_Identifier => Derived_Type,
5311 Subtype_Indication =>
5312 Make_Subtype_Indication (Loc,
5313 Subtype_Mark => New_Reference_To (Implicit_Base, Loc),
5314 Constraint => Constraint (Indic)));
5316 Rewrite (N, New_Indic);
5321 if Nkind (Indic) /= N_Subtype_Indication then
5324 Set_Ekind (Derived_Type, Ekind (Parent_Type));
5325 Set_Etype (Derived_Type, Implicit_Base);
5326 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5329 Error_Msg_N ("illegal constraint on constrained type", Indic);
5333 -- If parent type is not a derived type itself, and is declared in
5334 -- closed scope (e.g. a subprogram), then we must explicitly introduce
5335 -- the new type's concatenation operator since Derive_Subprograms
5336 -- will not inherit the parent's operator. If the parent type is
5337 -- unconstrained, the operator is of the unconstrained base type.
5339 if Number_Dimensions (Parent_Type) = 1
5340 and then not Is_Limited_Type (Parent_Type)
5341 and then not Is_Derived_Type (Parent_Type)
5342 and then not Is_Package_Or_Generic_Package
5343 (Scope (Base_Type (Parent_Type)))
5345 if not Is_Constrained (Parent_Type)
5346 and then Is_Constrained (Derived_Type)
5348 New_Concatenation_Op (Implicit_Base);
5350 New_Concatenation_Op (Derived_Type);
5353 end Build_Derived_Array_Type;
5355 -----------------------------------
5356 -- Build_Derived_Concurrent_Type --
5357 -----------------------------------
5359 procedure Build_Derived_Concurrent_Type
5361 Parent_Type : Entity_Id;
5362 Derived_Type : Entity_Id)
5364 Loc : constant Source_Ptr := Sloc (N);
5366 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
5367 Corr_Decl : Node_Id;
5368 Corr_Decl_Needed : Boolean;
5369 -- If the derived type has fewer discriminants than its parent, the
5370 -- corresponding record is also a derived type, in order to account for
5371 -- the bound discriminants. We create a full type declaration for it in
5374 Constraint_Present : constant Boolean :=
5375 Nkind (Subtype_Indication (Type_Definition (N))) =
5376 N_Subtype_Indication;
5378 D_Constraint : Node_Id;
5379 New_Constraint : Elist_Id;
5380 Old_Disc : Entity_Id;
5381 New_Disc : Entity_Id;
5385 Set_Stored_Constraint (Derived_Type, No_Elist);
5386 Corr_Decl_Needed := False;
5389 if Present (Discriminant_Specifications (N))
5390 and then Constraint_Present
5392 Old_Disc := First_Discriminant (Parent_Type);
5393 New_Disc := First (Discriminant_Specifications (N));
5394 while Present (New_Disc) and then Present (Old_Disc) loop
5395 Next_Discriminant (Old_Disc);
5400 if Present (Old_Disc) and then Expander_Active then
5402 -- The new type has fewer discriminants, so we need to create a new
5403 -- corresponding record, which is derived from the corresponding
5404 -- record of the parent, and has a stored constraint that captures
5405 -- the values of the discriminant constraints. The corresponding
5406 -- record is needed only if expander is active and code generation is
5409 -- The type declaration for the derived corresponding record has the
5410 -- same discriminant part and constraints as the current declaration.
5411 -- Copy the unanalyzed tree to build declaration.
5413 Corr_Decl_Needed := True;
5414 New_N := Copy_Separate_Tree (N);
5417 Make_Full_Type_Declaration (Loc,
5418 Defining_Identifier => Corr_Record,
5419 Discriminant_Specifications =>
5420 Discriminant_Specifications (New_N),
5422 Make_Derived_Type_Definition (Loc,
5423 Subtype_Indication =>
5424 Make_Subtype_Indication (Loc,
5427 (Corresponding_Record_Type (Parent_Type), Loc),
5430 (Subtype_Indication (Type_Definition (New_N))))));
5433 -- Copy Storage_Size and Relative_Deadline variables if task case
5435 if Is_Task_Type (Parent_Type) then
5436 Set_Storage_Size_Variable (Derived_Type,
5437 Storage_Size_Variable (Parent_Type));
5438 Set_Relative_Deadline_Variable (Derived_Type,
5439 Relative_Deadline_Variable (Parent_Type));
5442 if Present (Discriminant_Specifications (N)) then
5443 Push_Scope (Derived_Type);
5444 Check_Or_Process_Discriminants (N, Derived_Type);
5446 if Constraint_Present then
5448 Expand_To_Stored_Constraint
5450 Build_Discriminant_Constraints
5452 Subtype_Indication (Type_Definition (N)), True));
5457 elsif Constraint_Present then
5459 -- Build constrained subtype and derive from it
5462 Loc : constant Source_Ptr := Sloc (N);
5463 Anon : constant Entity_Id :=
5464 Make_Defining_Identifier (Loc,
5465 Chars => New_External_Name (Chars (Derived_Type), 'T'));
5470 Make_Subtype_Declaration (Loc,
5471 Defining_Identifier => Anon,
5472 Subtype_Indication =>
5473 Subtype_Indication (Type_Definition (N)));
5474 Insert_Before (N, Decl);
5477 Rewrite (Subtype_Indication (Type_Definition (N)),
5478 New_Occurrence_Of (Anon, Loc));
5479 Set_Analyzed (Derived_Type, False);
5485 -- By default, operations and private data are inherited from parent.
5486 -- However, in the presence of bound discriminants, a new corresponding
5487 -- record will be created, see below.
5489 Set_Has_Discriminants
5490 (Derived_Type, Has_Discriminants (Parent_Type));
5491 Set_Corresponding_Record_Type
5492 (Derived_Type, Corresponding_Record_Type (Parent_Type));
5494 -- Is_Constrained is set according the parent subtype, but is set to
5495 -- False if the derived type is declared with new discriminants.
5499 (Is_Constrained (Parent_Type) or else Constraint_Present)
5500 and then not Present (Discriminant_Specifications (N)));
5502 if Constraint_Present then
5503 if not Has_Discriminants (Parent_Type) then
5504 Error_Msg_N ("untagged parent must have discriminants", N);
5506 elsif Present (Discriminant_Specifications (N)) then
5508 -- Verify that new discriminants are used to constrain old ones
5513 (Constraint (Subtype_Indication (Type_Definition (N)))));
5515 Old_Disc := First_Discriminant (Parent_Type);
5517 while Present (D_Constraint) loop
5518 if Nkind (D_Constraint) /= N_Discriminant_Association then
5520 -- Positional constraint. If it is a reference to a new
5521 -- discriminant, it constrains the corresponding old one.
5523 if Nkind (D_Constraint) = N_Identifier then
5524 New_Disc := First_Discriminant (Derived_Type);
5525 while Present (New_Disc) loop
5526 exit when Chars (New_Disc) = Chars (D_Constraint);
5527 Next_Discriminant (New_Disc);
5530 if Present (New_Disc) then
5531 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
5535 Next_Discriminant (Old_Disc);
5537 -- if this is a named constraint, search by name for the old
5538 -- discriminants constrained by the new one.
5540 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
5542 -- Find new discriminant with that name
5544 New_Disc := First_Discriminant (Derived_Type);
5545 while Present (New_Disc) loop
5547 Chars (New_Disc) = Chars (Expression (D_Constraint));
5548 Next_Discriminant (New_Disc);
5551 if Present (New_Disc) then
5553 -- Verify that new discriminant renames some discriminant
5554 -- of the parent type, and associate the new discriminant
5555 -- with one or more old ones that it renames.
5561 Selector := First (Selector_Names (D_Constraint));
5562 while Present (Selector) loop
5563 Old_Disc := First_Discriminant (Parent_Type);
5564 while Present (Old_Disc) loop
5565 exit when Chars (Old_Disc) = Chars (Selector);
5566 Next_Discriminant (Old_Disc);
5569 if Present (Old_Disc) then
5570 Set_Corresponding_Discriminant
5571 (New_Disc, Old_Disc);
5580 Next (D_Constraint);
5583 New_Disc := First_Discriminant (Derived_Type);
5584 while Present (New_Disc) loop
5585 if No (Corresponding_Discriminant (New_Disc)) then
5587 ("new discriminant& must constrain old one", N, New_Disc);
5590 Subtypes_Statically_Compatible
5592 Etype (Corresponding_Discriminant (New_Disc)))
5595 ("& not statically compatible with parent discriminant",
5599 Next_Discriminant (New_Disc);
5603 elsif Present (Discriminant_Specifications (N)) then
5605 ("missing discriminant constraint in untagged derivation", N);
5608 -- The entity chain of the derived type includes the new discriminants
5609 -- but shares operations with the parent.
5611 if Present (Discriminant_Specifications (N)) then
5612 Old_Disc := First_Discriminant (Parent_Type);
5613 while Present (Old_Disc) loop
5614 if No (Next_Entity (Old_Disc))
5615 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
5618 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
5622 Next_Discriminant (Old_Disc);
5626 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
5627 if Has_Discriminants (Parent_Type) then
5628 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5629 Set_Discriminant_Constraint (
5630 Derived_Type, Discriminant_Constraint (Parent_Type));
5634 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
5636 Set_Has_Completion (Derived_Type);
5638 if Corr_Decl_Needed then
5639 Set_Stored_Constraint (Derived_Type, New_Constraint);
5640 Insert_After (N, Corr_Decl);
5641 Analyze (Corr_Decl);
5642 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
5644 end Build_Derived_Concurrent_Type;
5646 ------------------------------------
5647 -- Build_Derived_Enumeration_Type --
5648 ------------------------------------
5650 procedure Build_Derived_Enumeration_Type
5652 Parent_Type : Entity_Id;
5653 Derived_Type : Entity_Id)
5655 Loc : constant Source_Ptr := Sloc (N);
5656 Def : constant Node_Id := Type_Definition (N);
5657 Indic : constant Node_Id := Subtype_Indication (Def);
5658 Implicit_Base : Entity_Id;
5659 Literal : Entity_Id;
5660 New_Lit : Entity_Id;
5661 Literals_List : List_Id;
5662 Type_Decl : Node_Id;
5664 Rang_Expr : Node_Id;
5667 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
5668 -- not have explicit literals lists we need to process types derived
5669 -- from them specially. This is handled by Derived_Standard_Character.
5670 -- If the parent type is a generic type, there are no literals either,
5671 -- and we construct the same skeletal representation as for the generic
5674 if Is_Standard_Character_Type (Parent_Type) then
5675 Derived_Standard_Character (N, Parent_Type, Derived_Type);
5677 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
5683 if Nkind (Indic) /= N_Subtype_Indication then
5685 Make_Attribute_Reference (Loc,
5686 Attribute_Name => Name_First,
5687 Prefix => New_Reference_To (Derived_Type, Loc));
5688 Set_Etype (Lo, Derived_Type);
5691 Make_Attribute_Reference (Loc,
5692 Attribute_Name => Name_Last,
5693 Prefix => New_Reference_To (Derived_Type, Loc));
5694 Set_Etype (Hi, Derived_Type);
5696 Set_Scalar_Range (Derived_Type,
5702 -- Analyze subtype indication and verify compatibility
5703 -- with parent type.
5705 if Base_Type (Process_Subtype (Indic, N)) /=
5706 Base_Type (Parent_Type)
5709 ("illegal constraint for formal discrete type", N);
5715 -- If a constraint is present, analyze the bounds to catch
5716 -- premature usage of the derived literals.
5718 if Nkind (Indic) = N_Subtype_Indication
5719 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
5721 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
5722 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
5725 -- Introduce an implicit base type for the derived type even if there
5726 -- is no constraint attached to it, since this seems closer to the
5727 -- Ada semantics. Build a full type declaration tree for the derived
5728 -- type using the implicit base type as the defining identifier. The
5729 -- build a subtype declaration tree which applies the constraint (if
5730 -- any) have it replace the derived type declaration.
5732 Literal := First_Literal (Parent_Type);
5733 Literals_List := New_List;
5734 while Present (Literal)
5735 and then Ekind (Literal) = E_Enumeration_Literal
5737 -- Literals of the derived type have the same representation as
5738 -- those of the parent type, but this representation can be
5739 -- overridden by an explicit representation clause. Indicate
5740 -- that there is no explicit representation given yet. These
5741 -- derived literals are implicit operations of the new type,
5742 -- and can be overridden by explicit ones.
5744 if Nkind (Literal) = N_Defining_Character_Literal then
5746 Make_Defining_Character_Literal (Loc, Chars (Literal));
5748 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
5751 Set_Ekind (New_Lit, E_Enumeration_Literal);
5752 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
5753 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
5754 Set_Enumeration_Rep_Expr (New_Lit, Empty);
5755 Set_Alias (New_Lit, Literal);
5756 Set_Is_Known_Valid (New_Lit, True);
5758 Append (New_Lit, Literals_List);
5759 Next_Literal (Literal);
5763 Make_Defining_Identifier (Sloc (Derived_Type),
5764 Chars => New_External_Name (Chars (Derived_Type), 'B'));
5766 -- Indicate the proper nature of the derived type. This must be done
5767 -- before analysis of the literals, to recognize cases when a literal
5768 -- may be hidden by a previous explicit function definition (cf.
5771 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
5772 Set_Etype (Derived_Type, Implicit_Base);
5775 Make_Full_Type_Declaration (Loc,
5776 Defining_Identifier => Implicit_Base,
5777 Discriminant_Specifications => No_List,
5779 Make_Enumeration_Type_Definition (Loc, Literals_List));
5781 Mark_Rewrite_Insertion (Type_Decl);
5782 Insert_Before (N, Type_Decl);
5783 Analyze (Type_Decl);
5785 -- After the implicit base is analyzed its Etype needs to be changed
5786 -- to reflect the fact that it is derived from the parent type which
5787 -- was ignored during analysis. We also set the size at this point.
5789 Set_Etype (Implicit_Base, Parent_Type);
5791 Set_Size_Info (Implicit_Base, Parent_Type);
5792 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
5793 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
5795 -- Copy other flags from parent type
5797 Set_Has_Non_Standard_Rep
5798 (Implicit_Base, Has_Non_Standard_Rep
5800 Set_Has_Pragma_Ordered
5801 (Implicit_Base, Has_Pragma_Ordered
5803 Set_Has_Delayed_Freeze (Implicit_Base);
5805 -- Process the subtype indication including a validation check on the
5806 -- constraint, if any. If a constraint is given, its bounds must be
5807 -- implicitly converted to the new type.
5809 if Nkind (Indic) = N_Subtype_Indication then
5811 R : constant Node_Id :=
5812 Range_Expression (Constraint (Indic));
5815 if Nkind (R) = N_Range then
5816 Hi := Build_Scalar_Bound
5817 (High_Bound (R), Parent_Type, Implicit_Base);
5818 Lo := Build_Scalar_Bound
5819 (Low_Bound (R), Parent_Type, Implicit_Base);
5822 -- Constraint is a Range attribute. Replace with explicit
5823 -- mention of the bounds of the prefix, which must be a
5826 Analyze (Prefix (R));
5828 Convert_To (Implicit_Base,
5829 Make_Attribute_Reference (Loc,
5830 Attribute_Name => Name_Last,
5832 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
5835 Convert_To (Implicit_Base,
5836 Make_Attribute_Reference (Loc,
5837 Attribute_Name => Name_First,
5839 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
5846 (Type_High_Bound (Parent_Type),
5847 Parent_Type, Implicit_Base);
5850 (Type_Low_Bound (Parent_Type),
5851 Parent_Type, Implicit_Base);
5859 -- If we constructed a default range for the case where no range
5860 -- was given, then the expressions in the range must not freeze
5861 -- since they do not correspond to expressions in the source.
5863 if Nkind (Indic) /= N_Subtype_Indication then
5864 Set_Must_Not_Freeze (Lo);
5865 Set_Must_Not_Freeze (Hi);
5866 Set_Must_Not_Freeze (Rang_Expr);
5870 Make_Subtype_Declaration (Loc,
5871 Defining_Identifier => Derived_Type,
5872 Subtype_Indication =>
5873 Make_Subtype_Indication (Loc,
5874 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
5876 Make_Range_Constraint (Loc,
5877 Range_Expression => Rang_Expr))));
5881 -- If pragma Discard_Names applies on the first subtype of the parent
5882 -- type, then it must be applied on this subtype as well.
5884 if Einfo.Discard_Names (First_Subtype (Parent_Type)) then
5885 Set_Discard_Names (Derived_Type);
5888 -- Apply a range check. Since this range expression doesn't have an
5889 -- Etype, we have to specifically pass the Source_Typ parameter. Is
5892 if Nkind (Indic) = N_Subtype_Indication then
5893 Apply_Range_Check (Range_Expression (Constraint (Indic)),
5895 Source_Typ => Entity (Subtype_Mark (Indic)));
5898 end Build_Derived_Enumeration_Type;
5900 --------------------------------
5901 -- Build_Derived_Numeric_Type --
5902 --------------------------------
5904 procedure Build_Derived_Numeric_Type
5906 Parent_Type : Entity_Id;
5907 Derived_Type : Entity_Id)
5909 Loc : constant Source_Ptr := Sloc (N);
5910 Tdef : constant Node_Id := Type_Definition (N);
5911 Indic : constant Node_Id := Subtype_Indication (Tdef);
5912 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5913 No_Constraint : constant Boolean := Nkind (Indic) /=
5914 N_Subtype_Indication;
5915 Implicit_Base : Entity_Id;
5921 -- Process the subtype indication including a validation check on
5922 -- the constraint if any.
5924 Discard_Node (Process_Subtype (Indic, N));
5926 -- Introduce an implicit base type for the derived type even if there
5927 -- is no constraint attached to it, since this seems closer to the Ada
5931 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5933 Set_Etype (Implicit_Base, Parent_Base);
5934 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5935 Set_Size_Info (Implicit_Base, Parent_Base);
5936 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
5937 Set_Parent (Implicit_Base, Parent (Derived_Type));
5938 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
5940 -- Set RM Size for discrete type or decimal fixed-point type
5941 -- Ordinary fixed-point is excluded, why???
5943 if Is_Discrete_Type (Parent_Base)
5944 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
5946 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
5949 Set_Has_Delayed_Freeze (Implicit_Base);
5951 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
5952 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
5954 Set_Scalar_Range (Implicit_Base,
5959 if Has_Infinities (Parent_Base) then
5960 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
5963 -- The Derived_Type, which is the entity of the declaration, is a
5964 -- subtype of the implicit base. Its Ekind is a subtype, even in the
5965 -- absence of an explicit constraint.
5967 Set_Etype (Derived_Type, Implicit_Base);
5969 -- If we did not have a constraint, then the Ekind is set from the
5970 -- parent type (otherwise Process_Subtype has set the bounds)
5972 if No_Constraint then
5973 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
5976 -- If we did not have a range constraint, then set the range from the
5977 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
5980 or else not Has_Range_Constraint (Indic)
5982 Set_Scalar_Range (Derived_Type,
5984 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
5985 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
5986 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5988 if Has_Infinities (Parent_Type) then
5989 Set_Includes_Infinities (Scalar_Range (Derived_Type));
5992 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
5995 Set_Is_Descendent_Of_Address (Derived_Type,
5996 Is_Descendent_Of_Address (Parent_Type));
5997 Set_Is_Descendent_Of_Address (Implicit_Base,
5998 Is_Descendent_Of_Address (Parent_Type));
6000 -- Set remaining type-specific fields, depending on numeric type
6002 if Is_Modular_Integer_Type (Parent_Type) then
6003 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
6005 Set_Non_Binary_Modulus
6006 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
6009 (Implicit_Base, Is_Known_Valid (Parent_Base));
6011 elsif Is_Floating_Point_Type (Parent_Type) then
6013 -- Digits of base type is always copied from the digits value of
6014 -- the parent base type, but the digits of the derived type will
6015 -- already have been set if there was a constraint present.
6017 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6018 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
6020 if No_Constraint then
6021 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
6024 elsif Is_Fixed_Point_Type (Parent_Type) then
6026 -- Small of base type and derived type are always copied from the
6027 -- parent base type, since smalls never change. The delta of the
6028 -- base type is also copied from the parent base type. However the
6029 -- delta of the derived type will have been set already if a
6030 -- constraint was present.
6032 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
6033 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
6034 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
6036 if No_Constraint then
6037 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
6040 -- The scale and machine radix in the decimal case are always
6041 -- copied from the parent base type.
6043 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
6044 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
6045 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
6047 Set_Machine_Radix_10
6048 (Derived_Type, Machine_Radix_10 (Parent_Base));
6049 Set_Machine_Radix_10
6050 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6052 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6054 if No_Constraint then
6055 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6058 -- the analysis of the subtype_indication sets the
6059 -- digits value of the derived type.
6066 -- The type of the bounds is that of the parent type, and they
6067 -- must be converted to the derived type.
6069 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
6071 -- The implicit_base should be frozen when the derived type is frozen,
6072 -- but note that it is used in the conversions of the bounds. For fixed
6073 -- types we delay the determination of the bounds until the proper
6074 -- freezing point. For other numeric types this is rejected by GCC, for
6075 -- reasons that are currently unclear (???), so we choose to freeze the
6076 -- implicit base now. In the case of integers and floating point types
6077 -- this is harmless because subsequent representation clauses cannot
6078 -- affect anything, but it is still baffling that we cannot use the
6079 -- same mechanism for all derived numeric types.
6081 -- There is a further complication: actually *some* representation
6082 -- clauses can affect the implicit base type. Namely, attribute
6083 -- definition clauses for stream-oriented attributes need to set the
6084 -- corresponding TSS entries on the base type, and this normally cannot
6085 -- be done after the base type is frozen, so the circuitry in
6086 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility and
6087 -- not use Set_TSS in this case.
6089 if Is_Fixed_Point_Type (Parent_Type) then
6090 Conditional_Delay (Implicit_Base, Parent_Type);
6092 Freeze_Before (N, Implicit_Base);
6094 end Build_Derived_Numeric_Type;
6096 --------------------------------
6097 -- Build_Derived_Private_Type --
6098 --------------------------------
6100 procedure Build_Derived_Private_Type
6102 Parent_Type : Entity_Id;
6103 Derived_Type : Entity_Id;
6104 Is_Completion : Boolean;
6105 Derive_Subps : Boolean := True)
6107 Loc : constant Source_Ptr := Sloc (N);
6108 Der_Base : Entity_Id;
6110 Full_Decl : Node_Id := Empty;
6111 Full_Der : Entity_Id;
6113 Last_Discr : Entity_Id;
6114 Par_Scope : constant Entity_Id := Scope (Base_Type (Parent_Type));
6115 Swapped : Boolean := False;
6117 procedure Copy_And_Build;
6118 -- Copy derived type declaration, replace parent with its full view,
6119 -- and analyze new declaration.
6121 --------------------
6122 -- Copy_And_Build --
6123 --------------------
6125 procedure Copy_And_Build is
6129 if Ekind (Parent_Type) in Record_Kind
6131 (Ekind (Parent_Type) in Enumeration_Kind
6132 and then not Is_Standard_Character_Type (Parent_Type)
6133 and then not Is_Generic_Type (Root_Type (Parent_Type)))
6135 Full_N := New_Copy_Tree (N);
6136 Insert_After (N, Full_N);
6137 Build_Derived_Type (
6138 Full_N, Parent_Type, Full_Der, True, Derive_Subps => False);
6141 Build_Derived_Type (
6142 N, Parent_Type, Full_Der, True, Derive_Subps => False);
6146 -- Start of processing for Build_Derived_Private_Type
6149 if Is_Tagged_Type (Parent_Type) then
6150 Full_P := Full_View (Parent_Type);
6152 -- A type extension of a type with unknown discriminants is an
6153 -- indefinite type that the back-end cannot handle directly.
6154 -- We treat it as a private type, and build a completion that is
6155 -- derived from the full view of the parent, and hopefully has
6156 -- known discriminants.
6158 -- If the full view of the parent type has an underlying record view,
6159 -- use it to generate the underlying record view of this derived type
6160 -- (required for chains of derivations with unknown discriminants).
6162 -- Minor optimization: we avoid the generation of useless underlying
6163 -- record view entities if the private type declaration has unknown
6164 -- discriminants but its corresponding full view has no
6167 if Has_Unknown_Discriminants (Parent_Type)
6168 and then Present (Full_P)
6169 and then (Has_Discriminants (Full_P)
6170 or else Present (Underlying_Record_View (Full_P)))
6171 and then not In_Open_Scopes (Par_Scope)
6172 and then Expander_Active
6175 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
6176 New_Ext : constant Node_Id :=
6178 (Record_Extension_Part (Type_Definition (N)));
6182 Build_Derived_Record_Type
6183 (N, Parent_Type, Derived_Type, Derive_Subps);
6185 -- Build anonymous completion, as a derivation from the full
6186 -- view of the parent. This is not a completion in the usual
6187 -- sense, because the current type is not private.
6190 Make_Full_Type_Declaration (Loc,
6191 Defining_Identifier => Full_Der,
6193 Make_Derived_Type_Definition (Loc,
6194 Subtype_Indication =>
6196 (Subtype_Indication (Type_Definition (N))),
6197 Record_Extension_Part => New_Ext));
6199 -- If the parent type has an underlying record view, use it
6200 -- here to build the new underlying record view.
6202 if Present (Underlying_Record_View (Full_P)) then
6204 (Nkind (Subtype_Indication (Type_Definition (Decl)))
6206 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
6207 Underlying_Record_View (Full_P));
6210 Install_Private_Declarations (Par_Scope);
6211 Install_Visible_Declarations (Par_Scope);
6212 Insert_Before (N, Decl);
6214 -- Mark entity as an underlying record view before analysis,
6215 -- to avoid generating the list of its primitive operations
6216 -- (which is not really required for this entity) and thus
6217 -- prevent spurious errors associated with missing overriding
6218 -- of abstract primitives (overridden only for Derived_Type).
6220 Set_Ekind (Full_Der, E_Record_Type);
6221 Set_Is_Underlying_Record_View (Full_Der);
6225 pragma Assert (Has_Discriminants (Full_Der)
6226 and then not Has_Unknown_Discriminants (Full_Der));
6228 Uninstall_Declarations (Par_Scope);
6230 -- Freeze the underlying record view, to prevent generation of
6231 -- useless dispatching information, which is simply shared with
6232 -- the real derived type.
6234 Set_Is_Frozen (Full_Der);
6236 -- Set up links between real entity and underlying record view
6238 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
6239 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
6242 -- If discriminants are known, build derived record
6245 Build_Derived_Record_Type
6246 (N, Parent_Type, Derived_Type, Derive_Subps);
6251 elsif Has_Discriminants (Parent_Type) then
6252 if Present (Full_View (Parent_Type)) then
6253 if not Is_Completion then
6255 -- Copy declaration for subsequent analysis, to provide a
6256 -- completion for what is a private declaration. Indicate that
6257 -- the full type is internally generated.
6259 Full_Decl := New_Copy_Tree (N);
6260 Full_Der := New_Copy (Derived_Type);
6261 Set_Comes_From_Source (Full_Decl, False);
6262 Set_Comes_From_Source (Full_Der, False);
6263 Set_Parent (Full_Der, Full_Decl);
6265 Insert_After (N, Full_Decl);
6268 -- If this is a completion, the full view being built is itself
6269 -- private. We build a subtype of the parent with the same
6270 -- constraints as this full view, to convey to the back end the
6271 -- constrained components and the size of this subtype. If the
6272 -- parent is constrained, its full view can serve as the
6273 -- underlying full view of the derived type.
6275 if No (Discriminant_Specifications (N)) then
6276 if Nkind (Subtype_Indication (Type_Definition (N))) =
6277 N_Subtype_Indication
6279 Build_Underlying_Full_View (N, Derived_Type, Parent_Type);
6281 elsif Is_Constrained (Full_View (Parent_Type)) then
6282 Set_Underlying_Full_View
6283 (Derived_Type, Full_View (Parent_Type));
6287 -- If there are new discriminants, the parent subtype is
6288 -- constrained by them, but it is not clear how to build
6289 -- the Underlying_Full_View in this case???
6296 -- Build partial view of derived type from partial view of parent
6298 Build_Derived_Record_Type
6299 (N, Parent_Type, Derived_Type, Derive_Subps);
6301 if Present (Full_View (Parent_Type)) and then not Is_Completion then
6302 if not In_Open_Scopes (Par_Scope)
6303 or else not In_Same_Source_Unit (N, Parent_Type)
6305 -- Swap partial and full views temporarily
6307 Install_Private_Declarations (Par_Scope);
6308 Install_Visible_Declarations (Par_Scope);
6312 -- Build full view of derived type from full view of parent which
6313 -- is now installed. Subprograms have been derived on the partial
6314 -- view, the completion does not derive them anew.
6316 if not Is_Tagged_Type (Parent_Type) then
6318 -- If the parent is itself derived from another private type,
6319 -- installing the private declarations has not affected its
6320 -- privacy status, so use its own full view explicitly.
6322 if Is_Private_Type (Parent_Type) then
6323 Build_Derived_Record_Type
6324 (Full_Decl, Full_View (Parent_Type), Full_Der, False);
6326 Build_Derived_Record_Type
6327 (Full_Decl, Parent_Type, Full_Der, False);
6331 -- If full view of parent is tagged, the completion inherits
6332 -- the proper primitive operations.
6334 Set_Defining_Identifier (Full_Decl, Full_Der);
6335 Build_Derived_Record_Type
6336 (Full_Decl, Parent_Type, Full_Der, Derive_Subps);
6339 -- The full declaration has been introduced into the tree and
6340 -- processed in the step above. It should not be analyzed again
6341 -- (when encountered later in the current list of declarations)
6342 -- to prevent spurious name conflicts. The full entity remains
6345 Set_Analyzed (Full_Decl);
6348 Uninstall_Declarations (Par_Scope);
6350 if In_Open_Scopes (Par_Scope) then
6351 Install_Visible_Declarations (Par_Scope);
6355 Der_Base := Base_Type (Derived_Type);
6356 Set_Full_View (Derived_Type, Full_Der);
6357 Set_Full_View (Der_Base, Base_Type (Full_Der));
6359 -- Copy the discriminant list from full view to the partial views
6360 -- (base type and its subtype). Gigi requires that the partial and
6361 -- full views have the same discriminants.
6363 -- Note that since the partial view is pointing to discriminants
6364 -- in the full view, their scope will be that of the full view.
6365 -- This might cause some front end problems and need adjustment???
6367 Discr := First_Discriminant (Base_Type (Full_Der));
6368 Set_First_Entity (Der_Base, Discr);
6371 Last_Discr := Discr;
6372 Next_Discriminant (Discr);
6373 exit when No (Discr);
6376 Set_Last_Entity (Der_Base, Last_Discr);
6378 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
6379 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
6380 Set_Stored_Constraint (Full_Der, Stored_Constraint (Derived_Type));
6383 -- If this is a completion, the derived type stays private and
6384 -- there is no need to create a further full view, except in the
6385 -- unusual case when the derivation is nested within a child unit,
6391 elsif Present (Full_View (Parent_Type))
6392 and then Has_Discriminants (Full_View (Parent_Type))
6394 if Has_Unknown_Discriminants (Parent_Type)
6395 and then Nkind (Subtype_Indication (Type_Definition (N))) =
6396 N_Subtype_Indication
6399 ("cannot constrain type with unknown discriminants",
6400 Subtype_Indication (Type_Definition (N)));
6404 -- If full view of parent is a record type, build full view as a
6405 -- derivation from the parent's full view. Partial view remains
6406 -- private. For code generation and linking, the full view must have
6407 -- the same public status as the partial one. This full view is only
6408 -- needed if the parent type is in an enclosing scope, so that the
6409 -- full view may actually become visible, e.g. in a child unit. This
6410 -- is both more efficient, and avoids order of freezing problems with
6411 -- the added entities.
6413 if not Is_Private_Type (Full_View (Parent_Type))
6414 and then (In_Open_Scopes (Scope (Parent_Type)))
6417 Make_Defining_Identifier
6418 (Sloc (Derived_Type), Chars (Derived_Type));
6419 Set_Is_Itype (Full_Der);
6420 Set_Has_Private_Declaration (Full_Der);
6421 Set_Has_Private_Declaration (Derived_Type);
6422 Set_Associated_Node_For_Itype (Full_Der, N);
6423 Set_Parent (Full_Der, Parent (Derived_Type));
6424 Set_Full_View (Derived_Type, Full_Der);
6425 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
6426 Full_P := Full_View (Parent_Type);
6427 Exchange_Declarations (Parent_Type);
6429 Exchange_Declarations (Full_P);
6432 Build_Derived_Record_Type
6433 (N, Full_View (Parent_Type), Derived_Type,
6434 Derive_Subps => False);
6437 -- In any case, the primitive operations are inherited from the
6438 -- parent type, not from the internal full view.
6440 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
6442 if Derive_Subps then
6443 Derive_Subprograms (Parent_Type, Derived_Type);
6447 -- Untagged type, No discriminants on either view
6449 if Nkind (Subtype_Indication (Type_Definition (N))) =
6450 N_Subtype_Indication
6453 ("illegal constraint on type without discriminants", N);
6456 if Present (Discriminant_Specifications (N))
6457 and then Present (Full_View (Parent_Type))
6458 and then not Is_Tagged_Type (Full_View (Parent_Type))
6460 Error_Msg_N ("cannot add discriminants to untagged type", N);
6463 Set_Stored_Constraint (Derived_Type, No_Elist);
6464 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6465 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
6466 Set_Has_Controlled_Component
6467 (Derived_Type, Has_Controlled_Component
6470 -- Direct controlled types do not inherit Finalize_Storage_Only flag
6472 if not Is_Controlled (Parent_Type) then
6473 Set_Finalize_Storage_Only
6474 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
6477 -- Construct the implicit full view by deriving from full view of the
6478 -- parent type. In order to get proper visibility, we install the
6479 -- parent scope and its declarations.
6481 -- ??? If the parent is untagged private and its completion is
6482 -- tagged, this mechanism will not work because we cannot derive from
6483 -- the tagged full view unless we have an extension.
6485 if Present (Full_View (Parent_Type))
6486 and then not Is_Tagged_Type (Full_View (Parent_Type))
6487 and then not Is_Completion
6490 Make_Defining_Identifier
6491 (Sloc (Derived_Type), Chars (Derived_Type));
6492 Set_Is_Itype (Full_Der);
6493 Set_Has_Private_Declaration (Full_Der);
6494 Set_Has_Private_Declaration (Derived_Type);
6495 Set_Associated_Node_For_Itype (Full_Der, N);
6496 Set_Parent (Full_Der, Parent (Derived_Type));
6497 Set_Full_View (Derived_Type, Full_Der);
6499 if not In_Open_Scopes (Par_Scope) then
6500 Install_Private_Declarations (Par_Scope);
6501 Install_Visible_Declarations (Par_Scope);
6503 Uninstall_Declarations (Par_Scope);
6505 -- If parent scope is open and in another unit, and parent has a
6506 -- completion, then the derivation is taking place in the visible
6507 -- part of a child unit. In that case retrieve the full view of
6508 -- the parent momentarily.
6510 elsif not In_Same_Source_Unit (N, Parent_Type) then
6511 Full_P := Full_View (Parent_Type);
6512 Exchange_Declarations (Parent_Type);
6514 Exchange_Declarations (Full_P);
6516 -- Otherwise it is a local derivation
6522 Set_Scope (Full_Der, Current_Scope);
6523 Set_Is_First_Subtype (Full_Der,
6524 Is_First_Subtype (Derived_Type));
6525 Set_Has_Size_Clause (Full_Der, False);
6526 Set_Has_Alignment_Clause (Full_Der, False);
6527 Set_Next_Entity (Full_Der, Empty);
6528 Set_Has_Delayed_Freeze (Full_Der);
6529 Set_Is_Frozen (Full_Der, False);
6530 Set_Freeze_Node (Full_Der, Empty);
6531 Set_Depends_On_Private (Full_Der,
6532 Has_Private_Component (Full_Der));
6533 Set_Public_Status (Full_Der);
6537 Set_Has_Unknown_Discriminants (Derived_Type,
6538 Has_Unknown_Discriminants (Parent_Type));
6540 if Is_Private_Type (Derived_Type) then
6541 Set_Private_Dependents (Derived_Type, New_Elmt_List);
6544 if Is_Private_Type (Parent_Type)
6545 and then Base_Type (Parent_Type) = Parent_Type
6546 and then In_Open_Scopes (Scope (Parent_Type))
6548 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
6550 if Is_Child_Unit (Scope (Current_Scope))
6551 and then Is_Completion
6552 and then In_Private_Part (Current_Scope)
6553 and then Scope (Parent_Type) /= Current_Scope
6555 -- This is the unusual case where a type completed by a private
6556 -- derivation occurs within a package nested in a child unit, and
6557 -- the parent is declared in an ancestor. In this case, the full
6558 -- view of the parent type will become visible in the body of
6559 -- the enclosing child, and only then will the current type be
6560 -- possibly non-private. We build a underlying full view that
6561 -- will be installed when the enclosing child body is compiled.
6564 Make_Defining_Identifier
6565 (Sloc (Derived_Type), Chars (Derived_Type));
6566 Set_Is_Itype (Full_Der);
6567 Build_Itype_Reference (Full_Der, N);
6569 -- The full view will be used to swap entities on entry/exit to
6570 -- the body, and must appear in the entity list for the package.
6572 Append_Entity (Full_Der, Scope (Derived_Type));
6573 Set_Has_Private_Declaration (Full_Der);
6574 Set_Has_Private_Declaration (Derived_Type);
6575 Set_Associated_Node_For_Itype (Full_Der, N);
6576 Set_Parent (Full_Der, Parent (Derived_Type));
6577 Full_P := Full_View (Parent_Type);
6578 Exchange_Declarations (Parent_Type);
6580 Exchange_Declarations (Full_P);
6581 Set_Underlying_Full_View (Derived_Type, Full_Der);
6584 end Build_Derived_Private_Type;
6586 -------------------------------
6587 -- Build_Derived_Record_Type --
6588 -------------------------------
6592 -- Ideally we would like to use the same model of type derivation for
6593 -- tagged and untagged record types. Unfortunately this is not quite
6594 -- possible because the semantics of representation clauses is different
6595 -- for tagged and untagged records under inheritance. Consider the
6598 -- type R (...) is [tagged] record ... end record;
6599 -- type T (...) is new R (...) [with ...];
6601 -- The representation clauses for T can specify a completely different
6602 -- record layout from R's. Hence the same component can be placed in two
6603 -- very different positions in objects of type T and R. If R and T are
6604 -- tagged types, representation clauses for T can only specify the layout
6605 -- of non inherited components, thus components that are common in R and T
6606 -- have the same position in objects of type R and T.
6608 -- This has two implications. The first is that the entire tree for R's
6609 -- declaration needs to be copied for T in the untagged case, so that T
6610 -- can be viewed as a record type of its own with its own representation
6611 -- clauses. The second implication is the way we handle discriminants.
6612 -- Specifically, in the untagged case we need a way to communicate to Gigi
6613 -- what are the real discriminants in the record, while for the semantics
6614 -- we need to consider those introduced by the user to rename the
6615 -- discriminants in the parent type. This is handled by introducing the
6616 -- notion of stored discriminants. See below for more.
6618 -- Fortunately the way regular components are inherited can be handled in
6619 -- the same way in tagged and untagged types.
6621 -- To complicate things a bit more the private view of a private extension
6622 -- cannot be handled in the same way as the full view (for one thing the
6623 -- semantic rules are somewhat different). We will explain what differs
6626 -- 2. DISCRIMINANTS UNDER INHERITANCE
6628 -- The semantic rules governing the discriminants of derived types are
6631 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
6632 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
6634 -- If parent type has discriminants, then the discriminants that are
6635 -- declared in the derived type are [3.4 (11)]:
6637 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
6640 -- o Otherwise, each discriminant of the parent type (implicitly declared
6641 -- in the same order with the same specifications). In this case, the
6642 -- discriminants are said to be "inherited", or if unknown in the parent
6643 -- are also unknown in the derived type.
6645 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
6647 -- o The parent subtype shall be constrained;
6649 -- o If the parent type is not a tagged type, then each discriminant of
6650 -- the derived type shall be used in the constraint defining a parent
6651 -- subtype. [Implementation note: This ensures that the new discriminant
6652 -- can share storage with an existing discriminant.]
6654 -- For the derived type each discriminant of the parent type is either
6655 -- inherited, constrained to equal some new discriminant of the derived
6656 -- type, or constrained to the value of an expression.
6658 -- When inherited or constrained to equal some new discriminant, the
6659 -- parent discriminant and the discriminant of the derived type are said
6662 -- If a discriminant of the parent type is constrained to a specific value
6663 -- in the derived type definition, then the discriminant is said to be
6664 -- "specified" by that derived type definition.
6666 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
6668 -- We have spoken about stored discriminants in point 1 (introduction)
6669 -- above. There are two sort of stored discriminants: implicit and
6670 -- explicit. As long as the derived type inherits the same discriminants as
6671 -- the root record type, stored discriminants are the same as regular
6672 -- discriminants, and are said to be implicit. However, if any discriminant
6673 -- in the root type was renamed in the derived type, then the derived
6674 -- type will contain explicit stored discriminants. Explicit stored
6675 -- discriminants are discriminants in addition to the semantically visible
6676 -- discriminants defined for the derived type. Stored discriminants are
6677 -- used by Gigi to figure out what are the physical discriminants in
6678 -- objects of the derived type (see precise definition in einfo.ads).
6679 -- As an example, consider the following:
6681 -- type R (D1, D2, D3 : Int) is record ... end record;
6682 -- type T1 is new R;
6683 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
6684 -- type T3 is new T2;
6685 -- type T4 (Y : Int) is new T3 (Y, 99);
6687 -- The following table summarizes the discriminants and stored
6688 -- discriminants in R and T1 through T4.
6690 -- Type Discrim Stored Discrim Comment
6691 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
6692 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
6693 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
6694 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
6695 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
6697 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
6698 -- find the corresponding discriminant in the parent type, while
6699 -- Original_Record_Component (abbreviated ORC below), the actual physical
6700 -- component that is renamed. Finally the field Is_Completely_Hidden
6701 -- (abbreviated ICH below) is set for all explicit stored discriminants
6702 -- (see einfo.ads for more info). For the above example this gives:
6704 -- Discrim CD ORC ICH
6705 -- ^^^^^^^ ^^ ^^^ ^^^
6706 -- D1 in R empty itself no
6707 -- D2 in R empty itself no
6708 -- D3 in R empty itself no
6710 -- D1 in T1 D1 in R itself no
6711 -- D2 in T1 D2 in R itself no
6712 -- D3 in T1 D3 in R itself no
6714 -- X1 in T2 D3 in T1 D3 in T2 no
6715 -- X2 in T2 D1 in T1 D1 in T2 no
6716 -- D1 in T2 empty itself yes
6717 -- D2 in T2 empty itself yes
6718 -- D3 in T2 empty itself yes
6720 -- X1 in T3 X1 in T2 D3 in T3 no
6721 -- X2 in T3 X2 in T2 D1 in T3 no
6722 -- D1 in T3 empty itself yes
6723 -- D2 in T3 empty itself yes
6724 -- D3 in T3 empty itself yes
6726 -- Y in T4 X1 in T3 D3 in T3 no
6727 -- D1 in T3 empty itself yes
6728 -- D2 in T3 empty itself yes
6729 -- D3 in T3 empty itself yes
6731 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
6733 -- Type derivation for tagged types is fairly straightforward. If no
6734 -- discriminants are specified by the derived type, these are inherited
6735 -- from the parent. No explicit stored discriminants are ever necessary.
6736 -- The only manipulation that is done to the tree is that of adding a
6737 -- _parent field with parent type and constrained to the same constraint
6738 -- specified for the parent in the derived type definition. For instance:
6740 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
6741 -- type T1 is new R with null record;
6742 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
6744 -- are changed into:
6746 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
6747 -- _parent : R (D1, D2, D3);
6750 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
6751 -- _parent : T1 (X2, 88, X1);
6754 -- The discriminants actually present in R, T1 and T2 as well as their CD,
6755 -- ORC and ICH fields are:
6757 -- Discrim CD ORC ICH
6758 -- ^^^^^^^ ^^ ^^^ ^^^
6759 -- D1 in R empty itself no
6760 -- D2 in R empty itself no
6761 -- D3 in R empty itself no
6763 -- D1 in T1 D1 in R D1 in R no
6764 -- D2 in T1 D2 in R D2 in R no
6765 -- D3 in T1 D3 in R D3 in R no
6767 -- X1 in T2 D3 in T1 D3 in R no
6768 -- X2 in T2 D1 in T1 D1 in R no
6770 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
6772 -- Regardless of whether we dealing with a tagged or untagged type
6773 -- we will transform all derived type declarations of the form
6775 -- type T is new R (...) [with ...];
6777 -- subtype S is R (...);
6778 -- type T is new S [with ...];
6780 -- type BT is new R [with ...];
6781 -- subtype T is BT (...);
6783 -- That is, the base derived type is constrained only if it has no
6784 -- discriminants. The reason for doing this is that GNAT's semantic model
6785 -- assumes that a base type with discriminants is unconstrained.
6787 -- Note that, strictly speaking, the above transformation is not always
6788 -- correct. Consider for instance the following excerpt from ACVC b34011a:
6790 -- procedure B34011A is
6791 -- type REC (D : integer := 0) is record
6796 -- type T6 is new Rec;
6797 -- function F return T6;
6802 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
6805 -- The definition of Q6.U is illegal. However transforming Q6.U into
6807 -- type BaseU is new T6;
6808 -- subtype U is BaseU (Q6.F.I)
6810 -- turns U into a legal subtype, which is incorrect. To avoid this problem
6811 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
6812 -- the transformation described above.
6814 -- There is another instance where the above transformation is incorrect.
6818 -- type Base (D : Integer) is tagged null record;
6819 -- procedure P (X : Base);
6821 -- type Der is new Base (2) with null record;
6822 -- procedure P (X : Der);
6825 -- Then the above transformation turns this into
6827 -- type Der_Base is new Base with null record;
6828 -- -- procedure P (X : Base) is implicitly inherited here
6829 -- -- as procedure P (X : Der_Base).
6831 -- subtype Der is Der_Base (2);
6832 -- procedure P (X : Der);
6833 -- -- The overriding of P (X : Der_Base) is illegal since we
6834 -- -- have a parameter conformance problem.
6836 -- To get around this problem, after having semantically processed Der_Base
6837 -- and the rewritten subtype declaration for Der, we copy Der_Base field
6838 -- Discriminant_Constraint from Der so that when parameter conformance is
6839 -- checked when P is overridden, no semantic errors are flagged.
6841 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
6843 -- Regardless of whether we are dealing with a tagged or untagged type
6844 -- we will transform all derived type declarations of the form
6846 -- type R (D1, .., Dn : ...) is [tagged] record ...;
6847 -- type T is new R [with ...];
6849 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
6851 -- The reason for such transformation is that it allows us to implement a
6852 -- very clean form of component inheritance as explained below.
6854 -- Note that this transformation is not achieved by direct tree rewriting
6855 -- and manipulation, but rather by redoing the semantic actions that the
6856 -- above transformation will entail. This is done directly in routine
6857 -- Inherit_Components.
6859 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
6861 -- In both tagged and untagged derived types, regular non discriminant
6862 -- components are inherited in the derived type from the parent type. In
6863 -- the absence of discriminants component, inheritance is straightforward
6864 -- as components can simply be copied from the parent.
6866 -- If the parent has discriminants, inheriting components constrained with
6867 -- these discriminants requires caution. Consider the following example:
6869 -- type R (D1, D2 : Positive) is [tagged] record
6870 -- S : String (D1 .. D2);
6873 -- type T1 is new R [with null record];
6874 -- type T2 (X : positive) is new R (1, X) [with null record];
6876 -- As explained in 6. above, T1 is rewritten as
6877 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
6878 -- which makes the treatment for T1 and T2 identical.
6880 -- What we want when inheriting S, is that references to D1 and D2 in R are
6881 -- replaced with references to their correct constraints, i.e. D1 and D2 in
6882 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
6883 -- with either discriminant references in the derived type or expressions.
6884 -- This replacement is achieved as follows: before inheriting R's
6885 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
6886 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
6887 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
6888 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
6889 -- by String (1 .. X).
6891 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
6893 -- We explain here the rules governing private type extensions relevant to
6894 -- type derivation. These rules are explained on the following example:
6896 -- type D [(...)] is new A [(...)] with private; <-- partial view
6897 -- type D [(...)] is new P [(...)] with null record; <-- full view
6899 -- Type A is called the ancestor subtype of the private extension.
6900 -- Type P is the parent type of the full view of the private extension. It
6901 -- must be A or a type derived from A.
6903 -- The rules concerning the discriminants of private type extensions are
6906 -- o If a private extension inherits known discriminants from the ancestor
6907 -- subtype, then the full view shall also inherit its discriminants from
6908 -- the ancestor subtype and the parent subtype of the full view shall be
6909 -- constrained if and only if the ancestor subtype is constrained.
6911 -- o If a partial view has unknown discriminants, then the full view may
6912 -- define a definite or an indefinite subtype, with or without
6915 -- o If a partial view has neither known nor unknown discriminants, then
6916 -- the full view shall define a definite subtype.
6918 -- o If the ancestor subtype of a private extension has constrained
6919 -- discriminants, then the parent subtype of the full view shall impose a
6920 -- statically matching constraint on those discriminants.
6922 -- This means that only the following forms of private extensions are
6925 -- type D is new A with private; <-- partial view
6926 -- type D is new P with null record; <-- full view
6928 -- If A has no discriminants than P has no discriminants, otherwise P must
6929 -- inherit A's discriminants.
6931 -- type D is new A (...) with private; <-- partial view
6932 -- type D is new P (:::) with null record; <-- full view
6934 -- P must inherit A's discriminants and (...) and (:::) must statically
6937 -- subtype A is R (...);
6938 -- type D is new A with private; <-- partial view
6939 -- type D is new P with null record; <-- full view
6941 -- P must have inherited R's discriminants and must be derived from A or
6942 -- any of its subtypes.
6944 -- type D (..) is new A with private; <-- partial view
6945 -- type D (..) is new P [(:::)] with null record; <-- full view
6947 -- No specific constraints on P's discriminants or constraint (:::).
6948 -- Note that A can be unconstrained, but the parent subtype P must either
6949 -- be constrained or (:::) must be present.
6951 -- type D (..) is new A [(...)] with private; <-- partial view
6952 -- type D (..) is new P [(:::)] with null record; <-- full view
6954 -- P's constraints on A's discriminants must statically match those
6955 -- imposed by (...).
6957 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
6959 -- The full view of a private extension is handled exactly as described
6960 -- above. The model chose for the private view of a private extension is
6961 -- the same for what concerns discriminants (i.e. they receive the same
6962 -- treatment as in the tagged case). However, the private view of the
6963 -- private extension always inherits the components of the parent base,
6964 -- without replacing any discriminant reference. Strictly speaking this is
6965 -- incorrect. However, Gigi never uses this view to generate code so this
6966 -- is a purely semantic issue. In theory, a set of transformations similar
6967 -- to those given in 5. and 6. above could be applied to private views of
6968 -- private extensions to have the same model of component inheritance as
6969 -- for non private extensions. However, this is not done because it would
6970 -- further complicate private type processing. Semantically speaking, this
6971 -- leaves us in an uncomfortable situation. As an example consider:
6974 -- type R (D : integer) is tagged record
6975 -- S : String (1 .. D);
6977 -- procedure P (X : R);
6978 -- type T is new R (1) with private;
6980 -- type T is new R (1) with null record;
6983 -- This is transformed into:
6986 -- type R (D : integer) is tagged record
6987 -- S : String (1 .. D);
6989 -- procedure P (X : R);
6990 -- type T is new R (1) with private;
6992 -- type BaseT is new R with null record;
6993 -- subtype T is BaseT (1);
6996 -- (strictly speaking the above is incorrect Ada)
6998 -- From the semantic standpoint the private view of private extension T
6999 -- should be flagged as constrained since one can clearly have
7003 -- in a unit withing Pack. However, when deriving subprograms for the
7004 -- private view of private extension T, T must be seen as unconstrained
7005 -- since T has discriminants (this is a constraint of the current
7006 -- subprogram derivation model). Thus, when processing the private view of
7007 -- a private extension such as T, we first mark T as unconstrained, we
7008 -- process it, we perform program derivation and just before returning from
7009 -- Build_Derived_Record_Type we mark T as constrained.
7011 -- ??? Are there are other uncomfortable cases that we will have to
7014 -- 10. RECORD_TYPE_WITH_PRIVATE complications
7016 -- Types that are derived from a visible record type and have a private
7017 -- extension present other peculiarities. They behave mostly like private
7018 -- types, but if they have primitive operations defined, these will not
7019 -- have the proper signatures for further inheritance, because other
7020 -- primitive operations will use the implicit base that we define for
7021 -- private derivations below. This affect subprogram inheritance (see
7022 -- Derive_Subprograms for details). We also derive the implicit base from
7023 -- the base type of the full view, so that the implicit base is a record
7024 -- type and not another private type, This avoids infinite loops.
7026 procedure Build_Derived_Record_Type
7028 Parent_Type : Entity_Id;
7029 Derived_Type : Entity_Id;
7030 Derive_Subps : Boolean := True)
7032 Discriminant_Specs : constant Boolean :=
7033 Present (Discriminant_Specifications (N));
7034 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
7035 Loc : constant Source_Ptr := Sloc (N);
7036 Private_Extension : constant Boolean :=
7037 Nkind (N) = N_Private_Extension_Declaration;
7038 Assoc_List : Elist_Id;
7039 Constraint_Present : Boolean;
7041 Discrim : Entity_Id;
7043 Inherit_Discrims : Boolean := False;
7044 Last_Discrim : Entity_Id;
7045 New_Base : Entity_Id;
7047 New_Discrs : Elist_Id;
7048 New_Indic : Node_Id;
7049 Parent_Base : Entity_Id;
7050 Save_Etype : Entity_Id;
7051 Save_Discr_Constr : Elist_Id;
7052 Save_Next_Entity : Entity_Id;
7055 Discs : Elist_Id := New_Elmt_List;
7056 -- An empty Discs list means that there were no constraints in the
7057 -- subtype indication or that there was an error processing it.
7060 if Ekind (Parent_Type) = E_Record_Type_With_Private
7061 and then Present (Full_View (Parent_Type))
7062 and then Has_Discriminants (Parent_Type)
7064 Parent_Base := Base_Type (Full_View (Parent_Type));
7066 Parent_Base := Base_Type (Parent_Type);
7069 -- AI05-0115 : if this is a derivation from a private type in some
7070 -- other scope that may lead to invisible components for the derived
7071 -- type, mark it accordingly.
7073 if Is_Private_Type (Parent_Type) then
7074 if Scope (Parent_Type) = Scope (Derived_Type) then
7077 elsif In_Open_Scopes (Scope (Parent_Type))
7078 and then In_Private_Part (Scope (Parent_Type))
7083 Set_Has_Private_Ancestor (Derived_Type);
7087 Set_Has_Private_Ancestor
7088 (Derived_Type, Has_Private_Ancestor (Parent_Type));
7091 -- Before we start the previously documented transformations, here is
7092 -- little fix for size and alignment of tagged types. Normally when we
7093 -- derive type D from type P, we copy the size and alignment of P as the
7094 -- default for D, and in the absence of explicit representation clauses
7095 -- for D, the size and alignment are indeed the same as the parent.
7097 -- But this is wrong for tagged types, since fields may be added, and
7098 -- the default size may need to be larger, and the default alignment may
7099 -- need to be larger.
7101 -- We therefore reset the size and alignment fields in the tagged case.
7102 -- Note that the size and alignment will in any case be at least as
7103 -- large as the parent type (since the derived type has a copy of the
7104 -- parent type in the _parent field)
7106 -- The type is also marked as being tagged here, which is needed when
7107 -- processing components with a self-referential anonymous access type
7108 -- in the call to Check_Anonymous_Access_Components below. Note that
7109 -- this flag is also set later on for completeness.
7112 Set_Is_Tagged_Type (Derived_Type);
7113 Init_Size_Align (Derived_Type);
7116 -- STEP 0a: figure out what kind of derived type declaration we have
7118 if Private_Extension then
7120 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
7123 Type_Def := Type_Definition (N);
7125 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7126 -- Parent_Base can be a private type or private extension. However,
7127 -- for tagged types with an extension the newly added fields are
7128 -- visible and hence the Derived_Type is always an E_Record_Type.
7129 -- (except that the parent may have its own private fields).
7130 -- For untagged types we preserve the Ekind of the Parent_Base.
7132 if Present (Record_Extension_Part (Type_Def)) then
7133 Set_Ekind (Derived_Type, E_Record_Type);
7135 -- Create internal access types for components with anonymous
7138 if Ada_Version >= Ada_2005 then
7139 Check_Anonymous_Access_Components
7140 (N, Derived_Type, Derived_Type,
7141 Component_List (Record_Extension_Part (Type_Def)));
7145 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7149 -- Indic can either be an N_Identifier if the subtype indication
7150 -- contains no constraint or an N_Subtype_Indication if the subtype
7151 -- indication has a constraint.
7153 Indic := Subtype_Indication (Type_Def);
7154 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
7156 -- Check that the type has visible discriminants. The type may be
7157 -- a private type with unknown discriminants whose full view has
7158 -- discriminants which are invisible.
7160 if Constraint_Present then
7161 if not Has_Discriminants (Parent_Base)
7163 (Has_Unknown_Discriminants (Parent_Base)
7164 and then Is_Private_Type (Parent_Base))
7167 ("invalid constraint: type has no discriminant",
7168 Constraint (Indic));
7170 Constraint_Present := False;
7171 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7173 elsif Is_Constrained (Parent_Type) then
7175 ("invalid constraint: parent type is already constrained",
7176 Constraint (Indic));
7178 Constraint_Present := False;
7179 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7183 -- STEP 0b: If needed, apply transformation given in point 5. above
7185 if not Private_Extension
7186 and then Has_Discriminants (Parent_Type)
7187 and then not Discriminant_Specs
7188 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
7190 -- First, we must analyze the constraint (see comment in point 5.)
7192 if Constraint_Present then
7193 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
7195 if Has_Discriminants (Derived_Type)
7196 and then Has_Private_Declaration (Derived_Type)
7197 and then Present (Discriminant_Constraint (Derived_Type))
7199 -- Verify that constraints of the full view statically match
7200 -- those given in the partial view.
7206 C1 := First_Elmt (New_Discrs);
7207 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
7208 while Present (C1) and then Present (C2) loop
7209 if Fully_Conformant_Expressions (Node (C1), Node (C2))
7211 (Is_OK_Static_Expression (Node (C1))
7213 Is_OK_Static_Expression (Node (C2))
7215 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
7221 "constraint not conformant to previous declaration",
7232 -- Insert and analyze the declaration for the unconstrained base type
7234 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
7237 Make_Full_Type_Declaration (Loc,
7238 Defining_Identifier => New_Base,
7240 Make_Derived_Type_Definition (Loc,
7241 Abstract_Present => Abstract_Present (Type_Def),
7242 Limited_Present => Limited_Present (Type_Def),
7243 Subtype_Indication =>
7244 New_Occurrence_Of (Parent_Base, Loc),
7245 Record_Extension_Part =>
7246 Relocate_Node (Record_Extension_Part (Type_Def)),
7247 Interface_List => Interface_List (Type_Def)));
7249 Set_Parent (New_Decl, Parent (N));
7250 Mark_Rewrite_Insertion (New_Decl);
7251 Insert_Before (N, New_Decl);
7253 -- In the extension case, make sure ancestor is frozen appropriately
7254 -- (see also non-discriminated case below).
7256 if Present (Record_Extension_Part (Type_Def))
7257 or else Is_Interface (Parent_Base)
7259 Freeze_Before (New_Decl, Parent_Type);
7262 -- Note that this call passes False for the Derive_Subps parameter
7263 -- because subprogram derivation is deferred until after creating
7264 -- the subtype (see below).
7267 (New_Decl, Parent_Base, New_Base,
7268 Is_Completion => True, Derive_Subps => False);
7270 -- ??? This needs re-examination to determine whether the
7271 -- above call can simply be replaced by a call to Analyze.
7273 Set_Analyzed (New_Decl);
7275 -- Insert and analyze the declaration for the constrained subtype
7277 if Constraint_Present then
7279 Make_Subtype_Indication (Loc,
7280 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
7281 Constraint => Relocate_Node (Constraint (Indic)));
7285 Constr_List : constant List_Id := New_List;
7290 C := First_Elmt (Discriminant_Constraint (Parent_Type));
7291 while Present (C) loop
7294 -- It is safe here to call New_Copy_Tree since
7295 -- Force_Evaluation was called on each constraint in
7296 -- Build_Discriminant_Constraints.
7298 Append (New_Copy_Tree (Expr), To => Constr_List);
7304 Make_Subtype_Indication (Loc,
7305 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
7307 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
7312 Make_Subtype_Declaration (Loc,
7313 Defining_Identifier => Derived_Type,
7314 Subtype_Indication => New_Indic));
7318 -- Derivation of subprograms must be delayed until the full subtype
7319 -- has been established, to ensure proper overriding of subprograms
7320 -- inherited by full types. If the derivations occurred as part of
7321 -- the call to Build_Derived_Type above, then the check for type
7322 -- conformance would fail because earlier primitive subprograms
7323 -- could still refer to the full type prior the change to the new
7324 -- subtype and hence would not match the new base type created here.
7325 -- Subprograms are not derived, however, when Derive_Subps is False
7326 -- (since otherwise there could be redundant derivations).
7328 if Derive_Subps then
7329 Derive_Subprograms (Parent_Type, Derived_Type);
7332 -- For tagged types the Discriminant_Constraint of the new base itype
7333 -- is inherited from the first subtype so that no subtype conformance
7334 -- problem arise when the first subtype overrides primitive
7335 -- operations inherited by the implicit base type.
7338 Set_Discriminant_Constraint
7339 (New_Base, Discriminant_Constraint (Derived_Type));
7345 -- If we get here Derived_Type will have no discriminants or it will be
7346 -- a discriminated unconstrained base type.
7348 -- STEP 1a: perform preliminary actions/checks for derived tagged types
7352 -- The parent type is frozen for non-private extensions (RM 13.14(7))
7353 -- The declaration of a specific descendant of an interface type
7354 -- freezes the interface type (RM 13.14).
7356 if not Private_Extension or else Is_Interface (Parent_Base) then
7357 Freeze_Before (N, Parent_Type);
7360 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
7361 -- cannot be declared at a deeper level than its parent type is
7362 -- removed. The check on derivation within a generic body is also
7363 -- relaxed, but there's a restriction that a derived tagged type
7364 -- cannot be declared in a generic body if it's derived directly
7365 -- or indirectly from a formal type of that generic.
7367 if Ada_Version >= Ada_2005 then
7368 if Present (Enclosing_Generic_Body (Derived_Type)) then
7370 Ancestor_Type : Entity_Id;
7373 -- Check to see if any ancestor of the derived type is a
7376 Ancestor_Type := Parent_Type;
7377 while not Is_Generic_Type (Ancestor_Type)
7378 and then Etype (Ancestor_Type) /= Ancestor_Type
7380 Ancestor_Type := Etype (Ancestor_Type);
7383 -- If the derived type does have a formal type as an
7384 -- ancestor, then it's an error if the derived type is
7385 -- declared within the body of the generic unit that
7386 -- declares the formal type in its generic formal part. It's
7387 -- sufficient to check whether the ancestor type is declared
7388 -- inside the same generic body as the derived type (such as
7389 -- within a nested generic spec), in which case the
7390 -- derivation is legal. If the formal type is declared
7391 -- outside of that generic body, then it's guaranteed that
7392 -- the derived type is declared within the generic body of
7393 -- the generic unit declaring the formal type.
7395 if Is_Generic_Type (Ancestor_Type)
7396 and then Enclosing_Generic_Body (Ancestor_Type) /=
7397 Enclosing_Generic_Body (Derived_Type)
7400 ("parent type of& must not be descendant of formal type"
7401 & " of an enclosing generic body",
7402 Indic, Derived_Type);
7407 elsif Type_Access_Level (Derived_Type) /=
7408 Type_Access_Level (Parent_Type)
7409 and then not Is_Generic_Type (Derived_Type)
7411 if Is_Controlled (Parent_Type) then
7413 ("controlled type must be declared at the library level",
7417 ("type extension at deeper accessibility level than parent",
7423 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
7427 and then GB /= Enclosing_Generic_Body (Parent_Base)
7430 ("parent type of& must not be outside generic body"
7432 Indic, Derived_Type);
7438 -- Ada 2005 (AI-251)
7440 if Ada_Version >= Ada_2005 and then Is_Tagged then
7442 -- "The declaration of a specific descendant of an interface type
7443 -- freezes the interface type" (RM 13.14).
7448 if Is_Non_Empty_List (Interface_List (Type_Def)) then
7449 Iface := First (Interface_List (Type_Def));
7450 while Present (Iface) loop
7451 Freeze_Before (N, Etype (Iface));
7458 -- STEP 1b : preliminary cleanup of the full view of private types
7460 -- If the type is already marked as having discriminants, then it's the
7461 -- completion of a private type or private extension and we need to
7462 -- retain the discriminants from the partial view if the current
7463 -- declaration has Discriminant_Specifications so that we can verify
7464 -- conformance. However, we must remove any existing components that
7465 -- were inherited from the parent (and attached in Copy_And_Swap)
7466 -- because the full type inherits all appropriate components anyway, and
7467 -- we do not want the partial view's components interfering.
7469 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
7470 Discrim := First_Discriminant (Derived_Type);
7472 Last_Discrim := Discrim;
7473 Next_Discriminant (Discrim);
7474 exit when No (Discrim);
7477 Set_Last_Entity (Derived_Type, Last_Discrim);
7479 -- In all other cases wipe out the list of inherited components (even
7480 -- inherited discriminants), it will be properly rebuilt here.
7483 Set_First_Entity (Derived_Type, Empty);
7484 Set_Last_Entity (Derived_Type, Empty);
7487 -- STEP 1c: Initialize some flags for the Derived_Type
7489 -- The following flags must be initialized here so that
7490 -- Process_Discriminants can check that discriminants of tagged types do
7491 -- not have a default initial value and that access discriminants are
7492 -- only specified for limited records. For completeness, these flags are
7493 -- also initialized along with all the other flags below.
7495 -- AI-419: Limitedness is not inherited from an interface parent, so to
7496 -- be limited in that case the type must be explicitly declared as
7497 -- limited. However, task and protected interfaces are always limited.
7499 if Limited_Present (Type_Def) then
7500 Set_Is_Limited_Record (Derived_Type);
7502 elsif Is_Limited_Record (Parent_Type)
7503 or else (Present (Full_View (Parent_Type))
7504 and then Is_Limited_Record (Full_View (Parent_Type)))
7506 if not Is_Interface (Parent_Type)
7507 or else Is_Synchronized_Interface (Parent_Type)
7508 or else Is_Protected_Interface (Parent_Type)
7509 or else Is_Task_Interface (Parent_Type)
7511 Set_Is_Limited_Record (Derived_Type);
7515 -- STEP 2a: process discriminants of derived type if any
7517 Push_Scope (Derived_Type);
7519 if Discriminant_Specs then
7520 Set_Has_Unknown_Discriminants (Derived_Type, False);
7522 -- The following call initializes fields Has_Discriminants and
7523 -- Discriminant_Constraint, unless we are processing the completion
7524 -- of a private type declaration.
7526 Check_Or_Process_Discriminants (N, Derived_Type);
7528 -- For untagged types, the constraint on the Parent_Type must be
7529 -- present and is used to rename the discriminants.
7531 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
7532 Error_Msg_N ("untagged parent must have discriminants", Indic);
7534 elsif not Is_Tagged and then not Constraint_Present then
7536 ("discriminant constraint needed for derived untagged records",
7539 -- Otherwise the parent subtype must be constrained unless we have a
7540 -- private extension.
7542 elsif not Constraint_Present
7543 and then not Private_Extension
7544 and then not Is_Constrained (Parent_Type)
7547 ("unconstrained type not allowed in this context", Indic);
7549 elsif Constraint_Present then
7550 -- The following call sets the field Corresponding_Discriminant
7551 -- for the discriminants in the Derived_Type.
7553 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
7555 -- For untagged types all new discriminants must rename
7556 -- discriminants in the parent. For private extensions new
7557 -- discriminants cannot rename old ones (implied by [7.3(13)]).
7559 Discrim := First_Discriminant (Derived_Type);
7560 while Present (Discrim) loop
7562 and then No (Corresponding_Discriminant (Discrim))
7565 ("new discriminants must constrain old ones", Discrim);
7567 elsif Private_Extension
7568 and then Present (Corresponding_Discriminant (Discrim))
7571 ("only static constraints allowed for parent"
7572 & " discriminants in the partial view", Indic);
7576 -- If a new discriminant is used in the constraint, then its
7577 -- subtype must be statically compatible with the parent
7578 -- discriminant's subtype (3.7(15)).
7580 if Present (Corresponding_Discriminant (Discrim))
7582 not Subtypes_Statically_Compatible
7584 Etype (Corresponding_Discriminant (Discrim)))
7587 ("subtype must be compatible with parent discriminant",
7591 Next_Discriminant (Discrim);
7594 -- Check whether the constraints of the full view statically
7595 -- match those imposed by the parent subtype [7.3(13)].
7597 if Present (Stored_Constraint (Derived_Type)) then
7602 C1 := First_Elmt (Discs);
7603 C2 := First_Elmt (Stored_Constraint (Derived_Type));
7604 while Present (C1) and then Present (C2) loop
7606 Fully_Conformant_Expressions (Node (C1), Node (C2))
7609 ("not conformant with previous declaration",
7620 -- STEP 2b: No new discriminants, inherit discriminants if any
7623 if Private_Extension then
7624 Set_Has_Unknown_Discriminants
7626 Has_Unknown_Discriminants (Parent_Type)
7627 or else Unknown_Discriminants_Present (N));
7629 -- The partial view of the parent may have unknown discriminants,
7630 -- but if the full view has discriminants and the parent type is
7631 -- in scope they must be inherited.
7633 elsif Has_Unknown_Discriminants (Parent_Type)
7635 (not Has_Discriminants (Parent_Type)
7636 or else not In_Open_Scopes (Scope (Parent_Type)))
7638 Set_Has_Unknown_Discriminants (Derived_Type);
7641 if not Has_Unknown_Discriminants (Derived_Type)
7642 and then not Has_Unknown_Discriminants (Parent_Base)
7643 and then Has_Discriminants (Parent_Type)
7645 Inherit_Discrims := True;
7646 Set_Has_Discriminants
7647 (Derived_Type, True);
7648 Set_Discriminant_Constraint
7649 (Derived_Type, Discriminant_Constraint (Parent_Base));
7652 -- The following test is true for private types (remember
7653 -- transformation 5. is not applied to those) and in an error
7656 if Constraint_Present then
7657 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
7660 -- For now mark a new derived type as constrained only if it has no
7661 -- discriminants. At the end of Build_Derived_Record_Type we properly
7662 -- set this flag in the case of private extensions. See comments in
7663 -- point 9. just before body of Build_Derived_Record_Type.
7667 not (Inherit_Discrims
7668 or else Has_Unknown_Discriminants (Derived_Type)));
7671 -- STEP 3: initialize fields of derived type
7673 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
7674 Set_Stored_Constraint (Derived_Type, No_Elist);
7676 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
7677 -- but cannot be interfaces
7679 if not Private_Extension
7680 and then Ekind (Derived_Type) /= E_Private_Type
7681 and then Ekind (Derived_Type) /= E_Limited_Private_Type
7683 if Interface_Present (Type_Def) then
7684 Analyze_Interface_Declaration (Derived_Type, Type_Def);
7687 Set_Interfaces (Derived_Type, No_Elist);
7690 -- Fields inherited from the Parent_Type
7693 (Derived_Type, Einfo.Discard_Names (Parent_Type));
7694 Set_Has_Specified_Layout
7695 (Derived_Type, Has_Specified_Layout (Parent_Type));
7696 Set_Is_Limited_Composite
7697 (Derived_Type, Is_Limited_Composite (Parent_Type));
7698 Set_Is_Private_Composite
7699 (Derived_Type, Is_Private_Composite (Parent_Type));
7701 -- Fields inherited from the Parent_Base
7703 Set_Has_Controlled_Component
7704 (Derived_Type, Has_Controlled_Component (Parent_Base));
7705 Set_Has_Non_Standard_Rep
7706 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7707 Set_Has_Primitive_Operations
7708 (Derived_Type, Has_Primitive_Operations (Parent_Base));
7710 -- Fields inherited from the Parent_Base in the non-private case
7712 if Ekind (Derived_Type) = E_Record_Type then
7713 Set_Has_Complex_Representation
7714 (Derived_Type, Has_Complex_Representation (Parent_Base));
7717 -- Fields inherited from the Parent_Base for record types
7719 if Is_Record_Type (Derived_Type) then
7721 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7722 -- Parent_Base can be a private type or private extension.
7724 if Present (Full_View (Parent_Base)) then
7725 Set_OK_To_Reorder_Components
7727 OK_To_Reorder_Components (Full_View (Parent_Base)));
7728 Set_Reverse_Bit_Order
7729 (Derived_Type, Reverse_Bit_Order (Full_View (Parent_Base)));
7731 Set_OK_To_Reorder_Components
7732 (Derived_Type, OK_To_Reorder_Components (Parent_Base));
7733 Set_Reverse_Bit_Order
7734 (Derived_Type, Reverse_Bit_Order (Parent_Base));
7738 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7740 if not Is_Controlled (Parent_Type) then
7741 Set_Finalize_Storage_Only
7742 (Derived_Type, Finalize_Storage_Only (Parent_Type));
7745 -- Set fields for private derived types
7747 if Is_Private_Type (Derived_Type) then
7748 Set_Depends_On_Private (Derived_Type, True);
7749 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7751 -- Inherit fields from non private record types. If this is the
7752 -- completion of a derivation from a private type, the parent itself
7753 -- is private, and the attributes come from its full view, which must
7757 if Is_Private_Type (Parent_Base)
7758 and then not Is_Record_Type (Parent_Base)
7760 Set_Component_Alignment
7761 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
7763 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
7765 Set_Component_Alignment
7766 (Derived_Type, Component_Alignment (Parent_Base));
7768 (Derived_Type, C_Pass_By_Copy (Parent_Base));
7772 -- Set fields for tagged types
7775 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
7777 -- All tagged types defined in Ada.Finalization are controlled
7779 if Chars (Scope (Derived_Type)) = Name_Finalization
7780 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
7781 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
7783 Set_Is_Controlled (Derived_Type);
7785 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
7788 -- Minor optimization: there is no need to generate the class-wide
7789 -- entity associated with an underlying record view.
7791 if not Is_Underlying_Record_View (Derived_Type) then
7792 Make_Class_Wide_Type (Derived_Type);
7795 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
7797 if Has_Discriminants (Derived_Type)
7798 and then Constraint_Present
7800 Set_Stored_Constraint
7801 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
7804 if Ada_Version >= Ada_2005 then
7806 Ifaces_List : Elist_Id;
7809 -- Checks rules 3.9.4 (13/2 and 14/2)
7811 if Comes_From_Source (Derived_Type)
7812 and then not Is_Private_Type (Derived_Type)
7813 and then Is_Interface (Parent_Type)
7814 and then not Is_Interface (Derived_Type)
7816 if Is_Task_Interface (Parent_Type) then
7818 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
7821 elsif Is_Protected_Interface (Parent_Type) then
7823 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
7828 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
7830 Check_Interfaces (N, Type_Def);
7832 -- Ada 2005 (AI-251): Collect the list of progenitors that are
7833 -- not already in the parents.
7837 Ifaces_List => Ifaces_List,
7838 Exclude_Parents => True);
7840 Set_Interfaces (Derived_Type, Ifaces_List);
7842 -- If the derived type is the anonymous type created for
7843 -- a declaration whose parent has a constraint, propagate
7844 -- the interface list to the source type. This must be done
7845 -- prior to the completion of the analysis of the source type
7846 -- because the components in the extension may contain current
7847 -- instances whose legality depends on some ancestor.
7849 if Is_Itype (Derived_Type) then
7851 Def : constant Node_Id :=
7852 Associated_Node_For_Itype (Derived_Type);
7855 and then Nkind (Def) = N_Full_Type_Declaration
7858 (Defining_Identifier (Def), Ifaces_List);
7866 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
7867 Set_Has_Non_Standard_Rep
7868 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7871 -- STEP 4: Inherit components from the parent base and constrain them.
7872 -- Apply the second transformation described in point 6. above.
7874 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
7875 or else not Has_Discriminants (Parent_Type)
7876 or else not Is_Constrained (Parent_Type)
7880 Constrs := Discriminant_Constraint (Parent_Type);
7885 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
7887 -- STEP 5a: Copy the parent record declaration for untagged types
7889 if not Is_Tagged then
7891 -- Discriminant_Constraint (Derived_Type) has been properly
7892 -- constructed. Save it and temporarily set it to Empty because we
7893 -- do not want the call to New_Copy_Tree below to mess this list.
7895 if Has_Discriminants (Derived_Type) then
7896 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
7897 Set_Discriminant_Constraint (Derived_Type, No_Elist);
7899 Save_Discr_Constr := No_Elist;
7902 -- Save the Etype field of Derived_Type. It is correctly set now,
7903 -- but the call to New_Copy tree may remap it to point to itself,
7904 -- which is not what we want. Ditto for the Next_Entity field.
7906 Save_Etype := Etype (Derived_Type);
7907 Save_Next_Entity := Next_Entity (Derived_Type);
7909 -- Assoc_List maps all stored discriminants in the Parent_Base to
7910 -- stored discriminants in the Derived_Type. It is fundamental that
7911 -- no types or itypes with discriminants other than the stored
7912 -- discriminants appear in the entities declared inside
7913 -- Derived_Type, since the back end cannot deal with it.
7917 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
7919 -- Restore the fields saved prior to the New_Copy_Tree call
7920 -- and compute the stored constraint.
7922 Set_Etype (Derived_Type, Save_Etype);
7923 Set_Next_Entity (Derived_Type, Save_Next_Entity);
7925 if Has_Discriminants (Derived_Type) then
7926 Set_Discriminant_Constraint
7927 (Derived_Type, Save_Discr_Constr);
7928 Set_Stored_Constraint
7929 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
7930 Replace_Components (Derived_Type, New_Decl);
7931 Set_Has_Implicit_Dereference
7932 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
7935 -- Insert the new derived type declaration
7937 Rewrite (N, New_Decl);
7939 -- STEP 5b: Complete the processing for record extensions in generics
7941 -- There is no completion for record extensions declared in the
7942 -- parameter part of a generic, so we need to complete processing for
7943 -- these generic record extensions here. The Record_Type_Definition call
7944 -- will change the Ekind of the components from E_Void to E_Component.
7946 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
7947 Record_Type_Definition (Empty, Derived_Type);
7949 -- STEP 5c: Process the record extension for non private tagged types
7951 elsif not Private_Extension then
7953 -- Add the _parent field in the derived type
7955 Expand_Record_Extension (Derived_Type, Type_Def);
7957 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
7958 -- implemented interfaces if we are in expansion mode
7961 and then Has_Interfaces (Derived_Type)
7963 Add_Interface_Tag_Components (N, Derived_Type);
7966 -- Analyze the record extension
7968 Record_Type_Definition
7969 (Record_Extension_Part (Type_Def), Derived_Type);
7974 -- Nothing else to do if there is an error in the derivation.
7975 -- An unusual case: the full view may be derived from a type in an
7976 -- instance, when the partial view was used illegally as an actual
7977 -- in that instance, leading to a circular definition.
7979 if Etype (Derived_Type) = Any_Type
7980 or else Etype (Parent_Type) = Derived_Type
7985 -- Set delayed freeze and then derive subprograms, we need to do
7986 -- this in this order so that derived subprograms inherit the
7987 -- derived freeze if necessary.
7989 Set_Has_Delayed_Freeze (Derived_Type);
7991 if Derive_Subps then
7992 Derive_Subprograms (Parent_Type, Derived_Type);
7995 -- If we have a private extension which defines a constrained derived
7996 -- type mark as constrained here after we have derived subprograms. See
7997 -- comment on point 9. just above the body of Build_Derived_Record_Type.
7999 if Private_Extension and then Inherit_Discrims then
8000 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
8001 Set_Is_Constrained (Derived_Type, True);
8002 Set_Discriminant_Constraint (Derived_Type, Discs);
8004 elsif Is_Constrained (Parent_Type) then
8006 (Derived_Type, True);
8007 Set_Discriminant_Constraint
8008 (Derived_Type, Discriminant_Constraint (Parent_Type));
8012 -- Update the class-wide type, which shares the now-completed entity
8013 -- list with its specific type. In case of underlying record views,
8014 -- we do not generate the corresponding class wide entity.
8017 and then not Is_Underlying_Record_View (Derived_Type)
8020 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
8022 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
8024 end Build_Derived_Record_Type;
8026 ------------------------
8027 -- Build_Derived_Type --
8028 ------------------------
8030 procedure Build_Derived_Type
8032 Parent_Type : Entity_Id;
8033 Derived_Type : Entity_Id;
8034 Is_Completion : Boolean;
8035 Derive_Subps : Boolean := True)
8037 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
8040 -- Set common attributes
8042 Set_Scope (Derived_Type, Current_Scope);
8044 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8045 Set_Etype (Derived_Type, Parent_Base);
8046 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
8048 Set_Size_Info (Derived_Type, Parent_Type);
8049 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
8050 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
8051 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
8053 -- If the parent type is a private subtype, the convention on the base
8054 -- type may be set in the private part, and not propagated to the
8055 -- subtype until later, so we obtain the convention from the base type.
8057 Set_Convention (Derived_Type, Convention (Parent_Base));
8059 -- Propagate invariant information. The new type has invariants if
8060 -- they are inherited from the parent type, and these invariants can
8061 -- be further inherited, so both flags are set.
8063 if Has_Inheritable_Invariants (Parent_Type) then
8064 Set_Has_Inheritable_Invariants (Derived_Type);
8065 Set_Has_Invariants (Derived_Type);
8068 -- We similarly inherit predicates
8070 if Has_Predicates (Parent_Type) then
8071 Set_Has_Predicates (Derived_Type);
8074 -- The derived type inherits the representation clauses of the parent.
8075 -- However, for a private type that is completed by a derivation, there
8076 -- may be operation attributes that have been specified already (stream
8077 -- attributes and External_Tag) and those must be provided. Finally,
8078 -- if the partial view is a private extension, the representation items
8079 -- of the parent have been inherited already, and should not be chained
8080 -- twice to the derived type.
8082 if Is_Tagged_Type (Parent_Type)
8083 and then Present (First_Rep_Item (Derived_Type))
8085 -- The existing items are either operational items or items inherited
8086 -- from a private extension declaration.
8090 -- Used to iterate over representation items of the derived type
8093 -- Last representation item of the (non-empty) representation
8094 -- item list of the derived type.
8096 Found : Boolean := False;
8099 Rep := First_Rep_Item (Derived_Type);
8101 while Present (Rep) loop
8102 if Rep = First_Rep_Item (Parent_Type) then
8107 Rep := Next_Rep_Item (Rep);
8109 if Present (Rep) then
8115 -- Here if we either encountered the parent type's first rep
8116 -- item on the derived type's rep item list (in which case
8117 -- Found is True, and we have nothing else to do), or if we
8118 -- reached the last rep item of the derived type, which is
8119 -- Last_Rep, in which case we further chain the parent type's
8120 -- rep items to those of the derived type.
8123 Set_Next_Rep_Item (Last_Rep, First_Rep_Item (Parent_Type));
8128 Set_First_Rep_Item (Derived_Type, First_Rep_Item (Parent_Type));
8131 case Ekind (Parent_Type) is
8132 when Numeric_Kind =>
8133 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
8136 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
8140 | Class_Wide_Kind =>
8141 Build_Derived_Record_Type
8142 (N, Parent_Type, Derived_Type, Derive_Subps);
8145 when Enumeration_Kind =>
8146 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
8149 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
8151 when Incomplete_Or_Private_Kind =>
8152 Build_Derived_Private_Type
8153 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
8155 -- For discriminated types, the derivation includes deriving
8156 -- primitive operations. For others it is done below.
8158 if Is_Tagged_Type (Parent_Type)
8159 or else Has_Discriminants (Parent_Type)
8160 or else (Present (Full_View (Parent_Type))
8161 and then Has_Discriminants (Full_View (Parent_Type)))
8166 when Concurrent_Kind =>
8167 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
8170 raise Program_Error;
8173 if Etype (Derived_Type) = Any_Type then
8177 -- Set delayed freeze and then derive subprograms, we need to do this
8178 -- in this order so that derived subprograms inherit the derived freeze
8181 Set_Has_Delayed_Freeze (Derived_Type);
8182 if Derive_Subps then
8183 Derive_Subprograms (Parent_Type, Derived_Type);
8186 Set_Has_Primitive_Operations
8187 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
8188 end Build_Derived_Type;
8190 -----------------------
8191 -- Build_Discriminal --
8192 -----------------------
8194 procedure Build_Discriminal (Discrim : Entity_Id) is
8195 D_Minal : Entity_Id;
8196 CR_Disc : Entity_Id;
8199 -- A discriminal has the same name as the discriminant
8201 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8203 Set_Ekind (D_Minal, E_In_Parameter);
8204 Set_Mechanism (D_Minal, Default_Mechanism);
8205 Set_Etype (D_Minal, Etype (Discrim));
8206 Set_Scope (D_Minal, Current_Scope);
8208 Set_Discriminal (Discrim, D_Minal);
8209 Set_Discriminal_Link (D_Minal, Discrim);
8211 -- For task types, build at once the discriminants of the corresponding
8212 -- record, which are needed if discriminants are used in entry defaults
8213 -- and in family bounds.
8215 if Is_Concurrent_Type (Current_Scope)
8216 or else Is_Limited_Type (Current_Scope)
8218 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8220 Set_Ekind (CR_Disc, E_In_Parameter);
8221 Set_Mechanism (CR_Disc, Default_Mechanism);
8222 Set_Etype (CR_Disc, Etype (Discrim));
8223 Set_Scope (CR_Disc, Current_Scope);
8224 Set_Discriminal_Link (CR_Disc, Discrim);
8225 Set_CR_Discriminant (Discrim, CR_Disc);
8227 end Build_Discriminal;
8229 ------------------------------------
8230 -- Build_Discriminant_Constraints --
8231 ------------------------------------
8233 function Build_Discriminant_Constraints
8236 Derived_Def : Boolean := False) return Elist_Id
8238 C : constant Node_Id := Constraint (Def);
8239 Nb_Discr : constant Nat := Number_Discriminants (T);
8241 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
8242 -- Saves the expression corresponding to a given discriminant in T
8244 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
8245 -- Return the Position number within array Discr_Expr of a discriminant
8246 -- D within the discriminant list of the discriminated type T.
8252 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
8256 Disc := First_Discriminant (T);
8257 for J in Discr_Expr'Range loop
8262 Next_Discriminant (Disc);
8265 -- Note: Since this function is called on discriminants that are
8266 -- known to belong to the discriminated type, falling through the
8267 -- loop with no match signals an internal compiler error.
8269 raise Program_Error;
8272 -- Declarations local to Build_Discriminant_Constraints
8276 Elist : constant Elist_Id := New_Elmt_List;
8284 Discrim_Present : Boolean := False;
8286 -- Start of processing for Build_Discriminant_Constraints
8289 -- The following loop will process positional associations only.
8290 -- For a positional association, the (single) discriminant is
8291 -- implicitly specified by position, in textual order (RM 3.7.2).
8293 Discr := First_Discriminant (T);
8294 Constr := First (Constraints (C));
8295 for D in Discr_Expr'Range loop
8296 exit when Nkind (Constr) = N_Discriminant_Association;
8299 Error_Msg_N ("too few discriminants given in constraint", C);
8300 return New_Elmt_List;
8302 elsif Nkind (Constr) = N_Range
8303 or else (Nkind (Constr) = N_Attribute_Reference
8305 Attribute_Name (Constr) = Name_Range)
8308 ("a range is not a valid discriminant constraint", Constr);
8309 Discr_Expr (D) := Error;
8312 Analyze_And_Resolve (Constr, Base_Type (Etype (Discr)));
8313 Discr_Expr (D) := Constr;
8316 Next_Discriminant (Discr);
8320 if No (Discr) and then Present (Constr) then
8321 Error_Msg_N ("too many discriminants given in constraint", Constr);
8322 return New_Elmt_List;
8325 -- Named associations can be given in any order, but if both positional
8326 -- and named associations are used in the same discriminant constraint,
8327 -- then positional associations must occur first, at their normal
8328 -- position. Hence once a named association is used, the rest of the
8329 -- discriminant constraint must use only named associations.
8331 while Present (Constr) loop
8333 -- Positional association forbidden after a named association
8335 if Nkind (Constr) /= N_Discriminant_Association then
8336 Error_Msg_N ("positional association follows named one", Constr);
8337 return New_Elmt_List;
8339 -- Otherwise it is a named association
8342 -- E records the type of the discriminants in the named
8343 -- association. All the discriminants specified in the same name
8344 -- association must have the same type.
8348 -- Search the list of discriminants in T to see if the simple name
8349 -- given in the constraint matches any of them.
8351 Id := First (Selector_Names (Constr));
8352 while Present (Id) loop
8355 -- If Original_Discriminant is present, we are processing a
8356 -- generic instantiation and this is an instance node. We need
8357 -- to find the name of the corresponding discriminant in the
8358 -- actual record type T and not the name of the discriminant in
8359 -- the generic formal. Example:
8362 -- type G (D : int) is private;
8364 -- subtype W is G (D => 1);
8366 -- type Rec (X : int) is record ... end record;
8367 -- package Q is new P (G => Rec);
8369 -- At the point of the instantiation, formal type G is Rec
8370 -- and therefore when reanalyzing "subtype W is G (D => 1);"
8371 -- which really looks like "subtype W is Rec (D => 1);" at
8372 -- the point of instantiation, we want to find the discriminant
8373 -- that corresponds to D in Rec, i.e. X.
8375 if Present (Original_Discriminant (Id))
8376 and then In_Instance
8378 Discr := Find_Corresponding_Discriminant (Id, T);
8382 Discr := First_Discriminant (T);
8383 while Present (Discr) loop
8384 if Chars (Discr) = Chars (Id) then
8389 Next_Discriminant (Discr);
8393 Error_Msg_N ("& does not match any discriminant", Id);
8394 return New_Elmt_List;
8396 -- If the parent type is a generic formal, preserve the
8397 -- name of the discriminant for subsequent instances.
8398 -- see comment at the beginning of this if statement.
8400 elsif Is_Generic_Type (Root_Type (T)) then
8401 Set_Original_Discriminant (Id, Discr);
8405 Position := Pos_Of_Discr (T, Discr);
8407 if Present (Discr_Expr (Position)) then
8408 Error_Msg_N ("duplicate constraint for discriminant&", Id);
8411 -- Each discriminant specified in the same named association
8412 -- must be associated with a separate copy of the
8413 -- corresponding expression.
8415 if Present (Next (Id)) then
8416 Expr := New_Copy_Tree (Expression (Constr));
8417 Set_Parent (Expr, Parent (Expression (Constr)));
8419 Expr := Expression (Constr);
8422 Discr_Expr (Position) := Expr;
8423 Analyze_And_Resolve (Expr, Base_Type (Etype (Discr)));
8426 -- A discriminant association with more than one discriminant
8427 -- name is only allowed if the named discriminants are all of
8428 -- the same type (RM 3.7.1(8)).
8431 E := Base_Type (Etype (Discr));
8433 elsif Base_Type (Etype (Discr)) /= E then
8435 ("all discriminants in an association " &
8436 "must have the same type", Id);
8446 -- A discriminant constraint must provide exactly one value for each
8447 -- discriminant of the type (RM 3.7.1(8)).
8449 for J in Discr_Expr'Range loop
8450 if No (Discr_Expr (J)) then
8451 Error_Msg_N ("too few discriminants given in constraint", C);
8452 return New_Elmt_List;
8456 -- Determine if there are discriminant expressions in the constraint
8458 for J in Discr_Expr'Range loop
8459 if Denotes_Discriminant
8460 (Discr_Expr (J), Check_Concurrent => True)
8462 Discrim_Present := True;
8466 -- Build an element list consisting of the expressions given in the
8467 -- discriminant constraint and apply the appropriate checks. The list
8468 -- is constructed after resolving any named discriminant associations
8469 -- and therefore the expressions appear in the textual order of the
8472 Discr := First_Discriminant (T);
8473 for J in Discr_Expr'Range loop
8474 if Discr_Expr (J) /= Error then
8475 Append_Elmt (Discr_Expr (J), Elist);
8477 -- If any of the discriminant constraints is given by a
8478 -- discriminant and we are in a derived type declaration we
8479 -- have a discriminant renaming. Establish link between new
8480 -- and old discriminant.
8482 if Denotes_Discriminant (Discr_Expr (J)) then
8484 Set_Corresponding_Discriminant
8485 (Entity (Discr_Expr (J)), Discr);
8488 -- Force the evaluation of non-discriminant expressions.
8489 -- If we have found a discriminant in the constraint 3.4(26)
8490 -- and 3.8(18) demand that no range checks are performed are
8491 -- after evaluation. If the constraint is for a component
8492 -- definition that has a per-object constraint, expressions are
8493 -- evaluated but not checked either. In all other cases perform
8497 if Discrim_Present then
8500 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
8502 Has_Per_Object_Constraint
8503 (Defining_Identifier (Parent (Parent (Def))))
8507 elsif Is_Access_Type (Etype (Discr)) then
8508 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
8511 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
8514 Force_Evaluation (Discr_Expr (J));
8517 -- Check that the designated type of an access discriminant's
8518 -- expression is not a class-wide type unless the discriminant's
8519 -- designated type is also class-wide.
8521 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
8522 and then not Is_Class_Wide_Type
8523 (Designated_Type (Etype (Discr)))
8524 and then Etype (Discr_Expr (J)) /= Any_Type
8525 and then Is_Class_Wide_Type
8526 (Designated_Type (Etype (Discr_Expr (J))))
8528 Wrong_Type (Discr_Expr (J), Etype (Discr));
8530 elsif Is_Access_Type (Etype (Discr))
8531 and then not Is_Access_Constant (Etype (Discr))
8532 and then Is_Access_Type (Etype (Discr_Expr (J)))
8533 and then Is_Access_Constant (Etype (Discr_Expr (J)))
8536 ("constraint for discriminant& must be access to variable",
8541 Next_Discriminant (Discr);
8545 end Build_Discriminant_Constraints;
8547 ---------------------------------
8548 -- Build_Discriminated_Subtype --
8549 ---------------------------------
8551 procedure Build_Discriminated_Subtype
8555 Related_Nod : Node_Id;
8556 For_Access : Boolean := False)
8558 Has_Discrs : constant Boolean := Has_Discriminants (T);
8559 Constrained : constant Boolean :=
8561 and then not Is_Empty_Elmt_List (Elist)
8562 and then not Is_Class_Wide_Type (T))
8563 or else Is_Constrained (T);
8566 if Ekind (T) = E_Record_Type then
8568 Set_Ekind (Def_Id, E_Private_Subtype);
8569 Set_Is_For_Access_Subtype (Def_Id, True);
8571 Set_Ekind (Def_Id, E_Record_Subtype);
8574 -- Inherit preelaboration flag from base, for types for which it
8575 -- may have been set: records, private types, protected types.
8577 Set_Known_To_Have_Preelab_Init
8578 (Def_Id, Known_To_Have_Preelab_Init (T));
8580 elsif Ekind (T) = E_Task_Type then
8581 Set_Ekind (Def_Id, E_Task_Subtype);
8583 elsif Ekind (T) = E_Protected_Type then
8584 Set_Ekind (Def_Id, E_Protected_Subtype);
8585 Set_Known_To_Have_Preelab_Init
8586 (Def_Id, Known_To_Have_Preelab_Init (T));
8588 elsif Is_Private_Type (T) then
8589 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
8590 Set_Known_To_Have_Preelab_Init
8591 (Def_Id, Known_To_Have_Preelab_Init (T));
8593 elsif Is_Class_Wide_Type (T) then
8594 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
8597 -- Incomplete type. Attach subtype to list of dependents, to be
8598 -- completed with full view of parent type, unless is it the
8599 -- designated subtype of a record component within an init_proc.
8600 -- This last case arises for a component of an access type whose
8601 -- designated type is incomplete (e.g. a Taft Amendment type).
8602 -- The designated subtype is within an inner scope, and needs no
8603 -- elaboration, because only the access type is needed in the
8604 -- initialization procedure.
8606 Set_Ekind (Def_Id, Ekind (T));
8608 if For_Access and then Within_Init_Proc then
8611 Append_Elmt (Def_Id, Private_Dependents (T));
8615 Set_Etype (Def_Id, T);
8616 Init_Size_Align (Def_Id);
8617 Set_Has_Discriminants (Def_Id, Has_Discrs);
8618 Set_Is_Constrained (Def_Id, Constrained);
8620 Set_First_Entity (Def_Id, First_Entity (T));
8621 Set_Last_Entity (Def_Id, Last_Entity (T));
8622 Set_Has_Implicit_Dereference
8623 (Def_Id, Has_Implicit_Dereference (T));
8625 -- If the subtype is the completion of a private declaration, there may
8626 -- have been representation clauses for the partial view, and they must
8627 -- be preserved. Build_Derived_Type chains the inherited clauses with
8628 -- the ones appearing on the extension. If this comes from a subtype
8629 -- declaration, all clauses are inherited.
8631 if No (First_Rep_Item (Def_Id)) then
8632 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
8635 if Is_Tagged_Type (T) then
8636 Set_Is_Tagged_Type (Def_Id);
8637 Make_Class_Wide_Type (Def_Id);
8640 Set_Stored_Constraint (Def_Id, No_Elist);
8643 Set_Discriminant_Constraint (Def_Id, Elist);
8644 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
8647 if Is_Tagged_Type (T) then
8649 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
8650 -- concurrent record type (which has the list of primitive
8653 if Ada_Version >= Ada_2005
8654 and then Is_Concurrent_Type (T)
8656 Set_Corresponding_Record_Type (Def_Id,
8657 Corresponding_Record_Type (T));
8659 Set_Direct_Primitive_Operations (Def_Id,
8660 Direct_Primitive_Operations (T));
8663 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
8666 -- Subtypes introduced by component declarations do not need to be
8667 -- marked as delayed, and do not get freeze nodes, because the semantics
8668 -- verifies that the parents of the subtypes are frozen before the
8669 -- enclosing record is frozen.
8671 if not Is_Type (Scope (Def_Id)) then
8672 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
8674 if Is_Private_Type (T)
8675 and then Present (Full_View (T))
8677 Conditional_Delay (Def_Id, Full_View (T));
8679 Conditional_Delay (Def_Id, T);
8683 if Is_Record_Type (T) then
8684 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
8687 and then not Is_Empty_Elmt_List (Elist)
8688 and then not For_Access
8690 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
8691 elsif not For_Access then
8692 Set_Cloned_Subtype (Def_Id, T);
8695 end Build_Discriminated_Subtype;
8697 ---------------------------
8698 -- Build_Itype_Reference --
8699 ---------------------------
8701 procedure Build_Itype_Reference
8705 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
8708 -- Itype references are only created for use by the back-end
8710 if Inside_A_Generic then
8713 Set_Itype (IR, Ityp);
8714 Insert_After (Nod, IR);
8716 end Build_Itype_Reference;
8718 ------------------------
8719 -- Build_Scalar_Bound --
8720 ------------------------
8722 function Build_Scalar_Bound
8725 Der_T : Entity_Id) return Node_Id
8727 New_Bound : Entity_Id;
8730 -- Note: not clear why this is needed, how can the original bound
8731 -- be unanalyzed at this point? and if it is, what business do we
8732 -- have messing around with it? and why is the base type of the
8733 -- parent type the right type for the resolution. It probably is
8734 -- not! It is OK for the new bound we are creating, but not for
8735 -- the old one??? Still if it never happens, no problem!
8737 Analyze_And_Resolve (Bound, Base_Type (Par_T));
8739 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
8740 New_Bound := New_Copy (Bound);
8741 Set_Etype (New_Bound, Der_T);
8742 Set_Analyzed (New_Bound);
8744 elsif Is_Entity_Name (Bound) then
8745 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
8747 -- The following is almost certainly wrong. What business do we have
8748 -- relocating a node (Bound) that is presumably still attached to
8749 -- the tree elsewhere???
8752 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
8755 Set_Etype (New_Bound, Der_T);
8757 end Build_Scalar_Bound;
8759 --------------------------------
8760 -- Build_Underlying_Full_View --
8761 --------------------------------
8763 procedure Build_Underlying_Full_View
8768 Loc : constant Source_Ptr := Sloc (N);
8769 Subt : constant Entity_Id :=
8770 Make_Defining_Identifier
8771 (Loc, New_External_Name (Chars (Typ), 'S'));
8778 procedure Set_Discriminant_Name (Id : Node_Id);
8779 -- If the derived type has discriminants, they may rename discriminants
8780 -- of the parent. When building the full view of the parent, we need to
8781 -- recover the names of the original discriminants if the constraint is
8782 -- given by named associations.
8784 ---------------------------
8785 -- Set_Discriminant_Name --
8786 ---------------------------
8788 procedure Set_Discriminant_Name (Id : Node_Id) is
8792 Set_Original_Discriminant (Id, Empty);
8794 if Has_Discriminants (Typ) then
8795 Disc := First_Discriminant (Typ);
8796 while Present (Disc) loop
8797 if Chars (Disc) = Chars (Id)
8798 and then Present (Corresponding_Discriminant (Disc))
8800 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
8802 Next_Discriminant (Disc);
8805 end Set_Discriminant_Name;
8807 -- Start of processing for Build_Underlying_Full_View
8810 if Nkind (N) = N_Full_Type_Declaration then
8811 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
8813 elsif Nkind (N) = N_Subtype_Declaration then
8814 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
8816 elsif Nkind (N) = N_Component_Declaration then
8819 (Constraint (Subtype_Indication (Component_Definition (N))));
8822 raise Program_Error;
8825 C := First (Constraints (Constr));
8826 while Present (C) loop
8827 if Nkind (C) = N_Discriminant_Association then
8828 Id := First (Selector_Names (C));
8829 while Present (Id) loop
8830 Set_Discriminant_Name (Id);
8839 Make_Subtype_Declaration (Loc,
8840 Defining_Identifier => Subt,
8841 Subtype_Indication =>
8842 Make_Subtype_Indication (Loc,
8843 Subtype_Mark => New_Reference_To (Par, Loc),
8844 Constraint => New_Copy_Tree (Constr)));
8846 -- If this is a component subtype for an outer itype, it is not
8847 -- a list member, so simply set the parent link for analysis: if
8848 -- the enclosing type does not need to be in a declarative list,
8849 -- neither do the components.
8851 if Is_List_Member (N)
8852 and then Nkind (N) /= N_Component_Declaration
8854 Insert_Before (N, Indic);
8856 Set_Parent (Indic, Parent (N));
8860 Set_Underlying_Full_View (Typ, Full_View (Subt));
8861 end Build_Underlying_Full_View;
8863 -------------------------------
8864 -- Check_Abstract_Overriding --
8865 -------------------------------
8867 procedure Check_Abstract_Overriding (T : Entity_Id) is
8868 Alias_Subp : Entity_Id;
8874 procedure Check_Pragma_Implemented (Subp : Entity_Id);
8875 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
8876 -- which has pragma Implemented already set. Check whether Subp's entity
8877 -- kind conforms to the implementation kind of the overridden routine.
8879 procedure Check_Pragma_Implemented
8881 Iface_Subp : Entity_Id);
8882 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
8883 -- Iface_Subp and both entities have pragma Implemented already set on
8884 -- them. Check whether the two implementation kinds are conforming.
8886 procedure Inherit_Pragma_Implemented
8888 Iface_Subp : Entity_Id);
8889 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
8890 -- subprogram Iface_Subp which has been marked by pragma Implemented.
8891 -- Propagate the implementation kind of Iface_Subp to Subp.
8893 ------------------------------
8894 -- Check_Pragma_Implemented --
8895 ------------------------------
8897 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
8898 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
8899 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
8900 Contr_Typ : Entity_Id;
8903 -- Subp must have an alias since it is a hidden entity used to link
8904 -- an interface subprogram to its overriding counterpart.
8906 pragma Assert (Present (Alias (Subp)));
8908 -- Extract the type of the controlling formal
8910 Contr_Typ := Etype (First_Formal (Alias (Subp)));
8912 if Is_Concurrent_Record_Type (Contr_Typ) then
8913 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
8916 -- An interface subprogram whose implementation kind is By_Entry must
8917 -- be implemented by an entry.
8919 if Impl_Kind = Name_By_Entry
8920 and then Ekind (Wrapped_Entity (Alias (Subp))) /= E_Entry
8922 Error_Msg_Node_2 := Iface_Alias;
8924 ("type & must implement abstract subprogram & with an entry",
8925 Alias (Subp), Contr_Typ);
8927 elsif Impl_Kind = Name_By_Protected_Procedure then
8929 -- An interface subprogram whose implementation kind is By_
8930 -- Protected_Procedure cannot be implemented by a primitive
8931 -- procedure of a task type.
8933 if Ekind (Contr_Typ) /= E_Protected_Type then
8934 Error_Msg_Node_2 := Contr_Typ;
8936 ("interface subprogram & cannot be implemented by a " &
8937 "primitive procedure of task type &", Alias (Subp),
8940 -- An interface subprogram whose implementation kind is By_
8941 -- Protected_Procedure must be implemented by a procedure.
8943 elsif Is_Primitive_Wrapper (Alias (Subp))
8944 and then Ekind (Wrapped_Entity (Alias (Subp))) /= E_Procedure
8946 Error_Msg_Node_2 := Iface_Alias;
8948 ("type & must implement abstract subprogram & with a " &
8949 "procedure", Alias (Subp), Contr_Typ);
8952 end Check_Pragma_Implemented;
8954 ------------------------------
8955 -- Check_Pragma_Implemented --
8956 ------------------------------
8958 procedure Check_Pragma_Implemented
8960 Iface_Subp : Entity_Id)
8962 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
8963 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
8966 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
8967 -- and overriding subprogram are different. In general this is an
8968 -- error except when the implementation kind of the overridden
8969 -- subprograms is By_Any.
8971 if Iface_Kind /= Subp_Kind
8972 and then Iface_Kind /= Name_By_Any
8974 if Iface_Kind = Name_By_Entry then
8976 ("incompatible implementation kind, overridden subprogram " &
8977 "is marked By_Entry", Subp);
8980 ("incompatible implementation kind, overridden subprogram " &
8981 "is marked By_Protected_Procedure", Subp);
8984 end Check_Pragma_Implemented;
8986 --------------------------------
8987 -- Inherit_Pragma_Implemented --
8988 --------------------------------
8990 procedure Inherit_Pragma_Implemented
8992 Iface_Subp : Entity_Id)
8994 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
8995 Loc : constant Source_Ptr := Sloc (Subp);
8996 Impl_Prag : Node_Id;
8999 -- Since the implementation kind is stored as a representation item
9000 -- rather than a flag, create a pragma node.
9004 Chars => Name_Implemented,
9005 Pragma_Argument_Associations => New_List (
9006 Make_Pragma_Argument_Association (Loc,
9008 New_Reference_To (Subp, Loc)),
9010 Make_Pragma_Argument_Association (Loc,
9011 Expression => Make_Identifier (Loc, Iface_Kind))));
9013 -- The pragma doesn't need to be analyzed because it is internally
9014 -- build. It is safe to directly register it as a rep item since we
9015 -- are only interested in the characters of the implementation kind.
9017 Record_Rep_Item (Subp, Impl_Prag);
9018 end Inherit_Pragma_Implemented;
9020 -- Start of processing for Check_Abstract_Overriding
9023 Op_List := Primitive_Operations (T);
9025 -- Loop to check primitive operations
9027 Elmt := First_Elmt (Op_List);
9028 while Present (Elmt) loop
9029 Subp := Node (Elmt);
9030 Alias_Subp := Alias (Subp);
9032 -- Inherited subprograms are identified by the fact that they do not
9033 -- come from source, and the associated source location is the
9034 -- location of the first subtype of the derived type.
9036 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
9037 -- subprograms that "require overriding".
9039 -- Special exception, do not complain about failure to override the
9040 -- stream routines _Input and _Output, as well as the primitive
9041 -- operations used in dispatching selects since we always provide
9042 -- automatic overridings for these subprograms.
9044 -- Also ignore this rule for convention CIL since .NET libraries
9045 -- do bizarre things with interfaces???
9047 -- The partial view of T may have been a private extension, for
9048 -- which inherited functions dispatching on result are abstract.
9049 -- If the full view is a null extension, there is no need for
9050 -- overriding in Ada 2005, but wrappers need to be built for them
9051 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
9053 if Is_Null_Extension (T)
9054 and then Has_Controlling_Result (Subp)
9055 and then Ada_Version >= Ada_2005
9056 and then Present (Alias_Subp)
9057 and then not Comes_From_Source (Subp)
9058 and then not Is_Abstract_Subprogram (Alias_Subp)
9059 and then not Is_Access_Type (Etype (Subp))
9063 -- Ada 2005 (AI-251): Internal entities of interfaces need no
9064 -- processing because this check is done with the aliased
9067 elsif Present (Interface_Alias (Subp)) then
9070 elsif (Is_Abstract_Subprogram (Subp)
9071 or else Requires_Overriding (Subp)
9073 (Has_Controlling_Result (Subp)
9074 and then Present (Alias_Subp)
9075 and then not Comes_From_Source (Subp)
9076 and then Sloc (Subp) = Sloc (First_Subtype (T))))
9077 and then not Is_TSS (Subp, TSS_Stream_Input)
9078 and then not Is_TSS (Subp, TSS_Stream_Output)
9079 and then not Is_Abstract_Type (T)
9080 and then Convention (T) /= Convention_CIL
9081 and then not Is_Predefined_Interface_Primitive (Subp)
9083 -- Ada 2005 (AI-251): Do not consider hidden entities associated
9084 -- with abstract interface types because the check will be done
9085 -- with the aliased entity (otherwise we generate a duplicated
9088 and then not Present (Interface_Alias (Subp))
9090 if Present (Alias_Subp) then
9092 -- Only perform the check for a derived subprogram when the
9093 -- type has an explicit record extension. This avoids incorrect
9094 -- flagging of abstract subprograms for the case of a type
9095 -- without an extension that is derived from a formal type
9096 -- with a tagged actual (can occur within a private part).
9098 -- Ada 2005 (AI-391): In the case of an inherited function with
9099 -- a controlling result of the type, the rule does not apply if
9100 -- the type is a null extension (unless the parent function
9101 -- itself is abstract, in which case the function must still be
9102 -- be overridden). The expander will generate an overriding
9103 -- wrapper function calling the parent subprogram (see
9104 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
9106 Type_Def := Type_Definition (Parent (T));
9108 if Nkind (Type_Def) = N_Derived_Type_Definition
9109 and then Present (Record_Extension_Part (Type_Def))
9111 (Ada_Version < Ada_2005
9112 or else not Is_Null_Extension (T)
9113 or else Ekind (Subp) = E_Procedure
9114 or else not Has_Controlling_Result (Subp)
9115 or else Is_Abstract_Subprogram (Alias_Subp)
9116 or else Requires_Overriding (Subp)
9117 or else Is_Access_Type (Etype (Subp)))
9119 -- Avoid reporting error in case of abstract predefined
9120 -- primitive inherited from interface type because the
9121 -- body of internally generated predefined primitives
9122 -- of tagged types are generated later by Freeze_Type
9124 if Is_Interface (Root_Type (T))
9125 and then Is_Abstract_Subprogram (Subp)
9126 and then Is_Predefined_Dispatching_Operation (Subp)
9127 and then not Comes_From_Source (Ultimate_Alias (Subp))
9133 ("type must be declared abstract or & overridden",
9136 -- Traverse the whole chain of aliased subprograms to
9137 -- complete the error notification. This is especially
9138 -- useful for traceability of the chain of entities when
9139 -- the subprogram corresponds with an interface
9140 -- subprogram (which may be defined in another package).
9142 if Present (Alias_Subp) then
9148 while Present (Alias (E)) loop
9150 -- Avoid reporting redundant errors on entities
9151 -- inherited from interfaces
9153 if Sloc (E) /= Sloc (T) then
9154 Error_Msg_Sloc := Sloc (E);
9156 ("\& has been inherited #", T, Subp);
9162 Error_Msg_Sloc := Sloc (E);
9164 -- AI05-0068: report if there is an overriding
9165 -- non-abstract subprogram that is invisible.
9168 and then not Is_Abstract_Subprogram (E)
9171 ("\& subprogram# is not visible",
9176 ("\& has been inherited from subprogram #",
9183 -- Ada 2005 (AI-345): Protected or task type implementing
9184 -- abstract interfaces.
9186 elsif Is_Concurrent_Record_Type (T)
9187 and then Present (Interfaces (T))
9189 -- The controlling formal of Subp must be of mode "out",
9190 -- "in out" or an access-to-variable to be overridden.
9192 if Ekind (First_Formal (Subp)) = E_In_Parameter
9193 and then Ekind (Subp) /= E_Function
9195 if not Is_Predefined_Dispatching_Operation (Subp)
9196 and then Is_Protected_Type
9197 (Corresponding_Concurrent_Type (T))
9199 Error_Msg_PT (T, Subp);
9202 -- Some other kind of overriding failure
9206 ("interface subprogram & must be overridden",
9209 -- Examine primitive operations of synchronized type,
9210 -- to find homonyms that have the wrong profile.
9217 First_Entity (Corresponding_Concurrent_Type (T));
9218 while Present (Prim) loop
9219 if Chars (Prim) = Chars (Subp) then
9221 ("profile is not type conformant with "
9222 & "prefixed view profile of "
9223 & "inherited operation&", Prim, Subp);
9233 Error_Msg_Node_2 := T;
9235 ("abstract subprogram& not allowed for type&", Subp);
9237 -- Also post unconditional warning on the type (unconditional
9238 -- so that if there are more than one of these cases, we get
9239 -- them all, and not just the first one).
9241 Error_Msg_Node_2 := Subp;
9242 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
9246 -- Ada 2012 (AI05-0030): Perform some checks related to pragma
9249 -- Subp is an expander-generated procedure which maps an interface
9250 -- alias to a protected wrapper. The interface alias is flagged by
9251 -- pragma Implemented. Ensure that Subp is a procedure when the
9252 -- implementation kind is By_Protected_Procedure or an entry when
9255 if Ada_Version >= Ada_2012
9256 and then Is_Hidden (Subp)
9257 and then Present (Interface_Alias (Subp))
9258 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
9260 Check_Pragma_Implemented (Subp);
9263 -- Subp is an interface primitive which overrides another interface
9264 -- primitive marked with pragma Implemented.
9266 if Ada_Version >= Ada_2012
9267 and then Present (Overridden_Operation (Subp))
9268 and then Has_Rep_Pragma
9269 (Overridden_Operation (Subp), Name_Implemented)
9271 -- If the overriding routine is also marked by Implemented, check
9272 -- that the two implementation kinds are conforming.
9274 if Has_Rep_Pragma (Subp, Name_Implemented) then
9275 Check_Pragma_Implemented
9277 Iface_Subp => Overridden_Operation (Subp));
9279 -- Otherwise the overriding routine inherits the implementation
9280 -- kind from the overridden subprogram.
9283 Inherit_Pragma_Implemented
9285 Iface_Subp => Overridden_Operation (Subp));
9291 end Check_Abstract_Overriding;
9293 ------------------------------------------------
9294 -- Check_Access_Discriminant_Requires_Limited --
9295 ------------------------------------------------
9297 procedure Check_Access_Discriminant_Requires_Limited
9302 -- A discriminant_specification for an access discriminant shall appear
9303 -- only in the declaration for a task or protected type, or for a type
9304 -- with the reserved word 'limited' in its definition or in one of its
9305 -- ancestors (RM 3.7(10)).
9307 -- AI-0063: The proper condition is that type must be immutably limited,
9308 -- or else be a partial view.
9310 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
9311 if Is_Immutably_Limited_Type (Current_Scope)
9313 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
9314 and then Limited_Present (Parent (Current_Scope)))
9320 ("access discriminants allowed only for limited types", Loc);
9323 end Check_Access_Discriminant_Requires_Limited;
9325 -----------------------------------
9326 -- Check_Aliased_Component_Types --
9327 -----------------------------------
9329 procedure Check_Aliased_Component_Types (T : Entity_Id) is
9333 -- ??? Also need to check components of record extensions, but not
9334 -- components of protected types (which are always limited).
9336 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
9337 -- types to be unconstrained. This is safe because it is illegal to
9338 -- create access subtypes to such types with explicit discriminant
9341 if not Is_Limited_Type (T) then
9342 if Ekind (T) = E_Record_Type then
9343 C := First_Component (T);
9344 while Present (C) loop
9346 and then Has_Discriminants (Etype (C))
9347 and then not Is_Constrained (Etype (C))
9348 and then not In_Instance_Body
9349 and then Ada_Version < Ada_2005
9352 ("aliased component must be constrained (RM 3.6(11))",
9359 elsif Ekind (T) = E_Array_Type then
9360 if Has_Aliased_Components (T)
9361 and then Has_Discriminants (Component_Type (T))
9362 and then not Is_Constrained (Component_Type (T))
9363 and then not In_Instance_Body
9364 and then Ada_Version < Ada_2005
9367 ("aliased component type must be constrained (RM 3.6(11))",
9372 end Check_Aliased_Component_Types;
9374 ----------------------
9375 -- Check_Completion --
9376 ----------------------
9378 procedure Check_Completion (Body_Id : Node_Id := Empty) is
9381 procedure Post_Error;
9382 -- Post error message for lack of completion for entity E
9388 procedure Post_Error is
9390 procedure Missing_Body;
9391 -- Output missing body message
9397 procedure Missing_Body is
9399 -- Spec is in same unit, so we can post on spec
9401 if In_Same_Source_Unit (Body_Id, E) then
9402 Error_Msg_N ("missing body for &", E);
9404 -- Spec is in a separate unit, so we have to post on the body
9407 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
9411 -- Start of processing for Post_Error
9414 if not Comes_From_Source (E) then
9416 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
9417 -- It may be an anonymous protected type created for a
9418 -- single variable. Post error on variable, if present.
9424 Var := First_Entity (Current_Scope);
9425 while Present (Var) loop
9426 exit when Etype (Var) = E
9427 and then Comes_From_Source (Var);
9432 if Present (Var) then
9439 -- If a generated entity has no completion, then either previous
9440 -- semantic errors have disabled the expansion phase, or else we had
9441 -- missing subunits, or else we are compiling without expansion,
9442 -- or else something is very wrong.
9444 if not Comes_From_Source (E) then
9446 (Serious_Errors_Detected > 0
9447 or else Configurable_Run_Time_Violations > 0
9448 or else Subunits_Missing
9449 or else not Expander_Active);
9452 -- Here for source entity
9455 -- Here if no body to post the error message, so we post the error
9456 -- on the declaration that has no completion. This is not really
9457 -- the right place to post it, think about this later ???
9459 if No (Body_Id) then
9462 ("missing full declaration for }", Parent (E), E);
9464 Error_Msg_NE ("missing body for &", Parent (E), E);
9467 -- Package body has no completion for a declaration that appears
9468 -- in the corresponding spec. Post error on the body, with a
9469 -- reference to the non-completed declaration.
9472 Error_Msg_Sloc := Sloc (E);
9475 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
9477 elsif Is_Overloadable (E)
9478 and then Current_Entity_In_Scope (E) /= E
9480 -- It may be that the completion is mistyped and appears as
9481 -- a distinct overloading of the entity.
9484 Candidate : constant Entity_Id :=
9485 Current_Entity_In_Scope (E);
9486 Decl : constant Node_Id :=
9487 Unit_Declaration_Node (Candidate);
9490 if Is_Overloadable (Candidate)
9491 and then Ekind (Candidate) = Ekind (E)
9492 and then Nkind (Decl) = N_Subprogram_Body
9493 and then Acts_As_Spec (Decl)
9495 Check_Type_Conformant (Candidate, E);
9509 -- Start of processing for Check_Completion
9512 E := First_Entity (Current_Scope);
9513 while Present (E) loop
9514 if Is_Intrinsic_Subprogram (E) then
9517 -- The following situation requires special handling: a child unit
9518 -- that appears in the context clause of the body of its parent:
9520 -- procedure Parent.Child (...);
9522 -- with Parent.Child;
9523 -- package body Parent is
9525 -- Here Parent.Child appears as a local entity, but should not be
9526 -- flagged as requiring completion, because it is a compilation
9529 -- Ignore missing completion for a subprogram that does not come from
9530 -- source (including the _Call primitive operation of RAS types,
9531 -- which has to have the flag Comes_From_Source for other purposes):
9532 -- we assume that the expander will provide the missing completion.
9533 -- In case of previous errors, other expansion actions that provide
9534 -- bodies for null procedures with not be invoked, so inhibit message
9537 -- Note that E_Operator is not in the list that follows, because
9538 -- this kind is reserved for predefined operators, that are
9539 -- intrinsic and do not need completion.
9541 elsif Ekind (E) = E_Function
9542 or else Ekind (E) = E_Procedure
9543 or else Ekind (E) = E_Generic_Function
9544 or else Ekind (E) = E_Generic_Procedure
9546 if Has_Completion (E) then
9549 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
9552 elsif Is_Subprogram (E)
9553 and then (not Comes_From_Source (E)
9554 or else Chars (E) = Name_uCall)
9559 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
9563 elsif Nkind (Parent (E)) = N_Procedure_Specification
9564 and then Null_Present (Parent (E))
9565 and then Serious_Errors_Detected > 0
9573 elsif Is_Entry (E) then
9574 if not Has_Completion (E) and then
9575 (Ekind (Scope (E)) = E_Protected_Object
9576 or else Ekind (Scope (E)) = E_Protected_Type)
9581 elsif Is_Package_Or_Generic_Package (E) then
9582 if Unit_Requires_Body (E) then
9583 if not Has_Completion (E)
9584 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
9590 elsif not Is_Child_Unit (E) then
9591 May_Need_Implicit_Body (E);
9594 -- A formal incomplete type (Ada 2012) does not require a completion;
9595 -- other incomplete type declarations do.
9597 elsif Ekind (E) = E_Incomplete_Type
9598 and then No (Underlying_Type (E))
9599 and then not Is_Generic_Type (E)
9603 elsif (Ekind (E) = E_Task_Type or else
9604 Ekind (E) = E_Protected_Type)
9605 and then not Has_Completion (E)
9609 -- A single task declared in the current scope is a constant, verify
9610 -- that the body of its anonymous type is in the same scope. If the
9611 -- task is defined elsewhere, this may be a renaming declaration for
9612 -- which no completion is needed.
9614 elsif Ekind (E) = E_Constant
9615 and then Ekind (Etype (E)) = E_Task_Type
9616 and then not Has_Completion (Etype (E))
9617 and then Scope (Etype (E)) = Current_Scope
9621 elsif Ekind (E) = E_Protected_Object
9622 and then not Has_Completion (Etype (E))
9626 elsif Ekind (E) = E_Record_Type then
9627 if Is_Tagged_Type (E) then
9628 Check_Abstract_Overriding (E);
9629 Check_Conventions (E);
9632 Check_Aliased_Component_Types (E);
9634 elsif Ekind (E) = E_Array_Type then
9635 Check_Aliased_Component_Types (E);
9641 end Check_Completion;
9643 ----------------------------
9644 -- Check_Delta_Expression --
9645 ----------------------------
9647 procedure Check_Delta_Expression (E : Node_Id) is
9649 if not (Is_Real_Type (Etype (E))) then
9650 Wrong_Type (E, Any_Real);
9652 elsif not Is_OK_Static_Expression (E) then
9653 Flag_Non_Static_Expr
9654 ("non-static expression used for delta value!", E);
9656 elsif not UR_Is_Positive (Expr_Value_R (E)) then
9657 Error_Msg_N ("delta expression must be positive", E);
9663 -- If any of above errors occurred, then replace the incorrect
9664 -- expression by the real 0.1, which should prevent further errors.
9667 Make_Real_Literal (Sloc (E), Ureal_Tenth));
9668 Analyze_And_Resolve (E, Standard_Float);
9669 end Check_Delta_Expression;
9671 -----------------------------
9672 -- Check_Digits_Expression --
9673 -----------------------------
9675 procedure Check_Digits_Expression (E : Node_Id) is
9677 if not (Is_Integer_Type (Etype (E))) then
9678 Wrong_Type (E, Any_Integer);
9680 elsif not Is_OK_Static_Expression (E) then
9681 Flag_Non_Static_Expr
9682 ("non-static expression used for digits value!", E);
9684 elsif Expr_Value (E) <= 0 then
9685 Error_Msg_N ("digits value must be greater than zero", E);
9691 -- If any of above errors occurred, then replace the incorrect
9692 -- expression by the integer 1, which should prevent further errors.
9694 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
9695 Analyze_And_Resolve (E, Standard_Integer);
9697 end Check_Digits_Expression;
9699 --------------------------
9700 -- Check_Initialization --
9701 --------------------------
9703 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
9705 if Is_Limited_Type (T)
9706 and then not In_Instance
9707 and then not In_Inlined_Body
9709 if not OK_For_Limited_Init (T, Exp) then
9711 -- In GNAT mode, this is just a warning, to allow it to be evilly
9712 -- turned off. Otherwise it is a real error.
9716 ("?cannot initialize entities of limited type!", Exp);
9718 elsif Ada_Version < Ada_2005 then
9720 -- The side effect removal machinery may generate illegal Ada
9721 -- code to avoid the usage of access types and 'reference in
9722 -- Alfa mode. Since this is legal code with respect to theorem
9723 -- proving, do not emit the error.
9726 and then Nkind (Exp) = N_Function_Call
9727 and then Nkind (Parent (Exp)) = N_Object_Declaration
9728 and then not Comes_From_Source
9729 (Defining_Identifier (Parent (Exp)))
9735 ("cannot initialize entities of limited type", Exp);
9736 Explain_Limited_Type (T, Exp);
9740 -- Specialize error message according to kind of illegal
9741 -- initial expression.
9743 if Nkind (Exp) = N_Type_Conversion
9744 and then Nkind (Expression (Exp)) = N_Function_Call
9747 ("illegal context for call"
9748 & " to function with limited result", Exp);
9752 ("initialization of limited object requires aggregate "
9753 & "or function call", Exp);
9758 end Check_Initialization;
9760 ----------------------
9761 -- Check_Interfaces --
9762 ----------------------
9764 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
9765 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
9768 Iface_Def : Node_Id;
9769 Iface_Typ : Entity_Id;
9770 Parent_Node : Node_Id;
9772 Is_Task : Boolean := False;
9773 -- Set True if parent type or any progenitor is a task interface
9775 Is_Protected : Boolean := False;
9776 -- Set True if parent type or any progenitor is a protected interface
9778 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
9779 -- Check that a progenitor is compatible with declaration.
9780 -- Error is posted on Error_Node.
9786 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
9787 Iface_Id : constant Entity_Id :=
9788 Defining_Identifier (Parent (Iface_Def));
9792 if Nkind (N) = N_Private_Extension_Declaration then
9795 Type_Def := Type_Definition (N);
9798 if Is_Task_Interface (Iface_Id) then
9801 elsif Is_Protected_Interface (Iface_Id) then
9802 Is_Protected := True;
9805 if Is_Synchronized_Interface (Iface_Id) then
9807 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
9808 -- extension derived from a synchronized interface must explicitly
9809 -- be declared synchronized, because the full view will be a
9810 -- synchronized type.
9812 if Nkind (N) = N_Private_Extension_Declaration then
9813 if not Synchronized_Present (N) then
9815 ("private extension of& must be explicitly synchronized",
9819 -- However, by 3.9.4(16/2), a full type that is a record extension
9820 -- is never allowed to derive from a synchronized interface (note
9821 -- that interfaces must be excluded from this check, because those
9822 -- are represented by derived type definitions in some cases).
9824 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9825 and then not Interface_Present (Type_Definition (N))
9827 Error_Msg_N ("record extension cannot derive from synchronized"
9828 & " interface", Error_Node);
9832 -- Check that the characteristics of the progenitor are compatible
9833 -- with the explicit qualifier in the declaration.
9834 -- The check only applies to qualifiers that come from source.
9835 -- Limited_Present also appears in the declaration of corresponding
9836 -- records, and the check does not apply to them.
9838 if Limited_Present (Type_Def)
9840 Is_Concurrent_Record_Type (Defining_Identifier (N))
9842 if Is_Limited_Interface (Parent_Type)
9843 and then not Is_Limited_Interface (Iface_Id)
9846 ("progenitor& must be limited interface",
9847 Error_Node, Iface_Id);
9850 (Task_Present (Iface_Def)
9851 or else Protected_Present (Iface_Def)
9852 or else Synchronized_Present (Iface_Def))
9853 and then Nkind (N) /= N_Private_Extension_Declaration
9854 and then not Error_Posted (N)
9857 ("progenitor& must be limited interface",
9858 Error_Node, Iface_Id);
9861 -- Protected interfaces can only inherit from limited, synchronized
9862 -- or protected interfaces.
9864 elsif Nkind (N) = N_Full_Type_Declaration
9865 and then Protected_Present (Type_Def)
9867 if Limited_Present (Iface_Def)
9868 or else Synchronized_Present (Iface_Def)
9869 or else Protected_Present (Iface_Def)
9873 elsif Task_Present (Iface_Def) then
9874 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9875 & " from task interface", Error_Node);
9878 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9879 & " from non-limited interface", Error_Node);
9882 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
9883 -- limited and synchronized.
9885 elsif Synchronized_Present (Type_Def) then
9886 if Limited_Present (Iface_Def)
9887 or else Synchronized_Present (Iface_Def)
9891 elsif Protected_Present (Iface_Def)
9892 and then Nkind (N) /= N_Private_Extension_Declaration
9894 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9895 & " from protected interface", Error_Node);
9897 elsif Task_Present (Iface_Def)
9898 and then Nkind (N) /= N_Private_Extension_Declaration
9900 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9901 & " from task interface", Error_Node);
9903 elsif not Is_Limited_Interface (Iface_Id) then
9904 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9905 & " from non-limited interface", Error_Node);
9908 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
9909 -- synchronized or task interfaces.
9911 elsif Nkind (N) = N_Full_Type_Declaration
9912 and then Task_Present (Type_Def)
9914 if Limited_Present (Iface_Def)
9915 or else Synchronized_Present (Iface_Def)
9916 or else Task_Present (Iface_Def)
9920 elsif Protected_Present (Iface_Def) then
9921 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9922 & " protected interface", Error_Node);
9925 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9926 & " non-limited interface", Error_Node);
9931 -- Start of processing for Check_Interfaces
9934 if Is_Interface (Parent_Type) then
9935 if Is_Task_Interface (Parent_Type) then
9938 elsif Is_Protected_Interface (Parent_Type) then
9939 Is_Protected := True;
9943 if Nkind (N) = N_Private_Extension_Declaration then
9945 -- Check that progenitors are compatible with declaration
9947 Iface := First (Interface_List (Def));
9948 while Present (Iface) loop
9949 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9951 Parent_Node := Parent (Base_Type (Iface_Typ));
9952 Iface_Def := Type_Definition (Parent_Node);
9954 if not Is_Interface (Iface_Typ) then
9955 Diagnose_Interface (Iface, Iface_Typ);
9958 Check_Ifaces (Iface_Def, Iface);
9964 if Is_Task and Is_Protected then
9966 ("type cannot derive from task and protected interface", N);
9972 -- Full type declaration of derived type.
9973 -- Check compatibility with parent if it is interface type
9975 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9976 and then Is_Interface (Parent_Type)
9978 Parent_Node := Parent (Parent_Type);
9980 -- More detailed checks for interface varieties
9983 (Iface_Def => Type_Definition (Parent_Node),
9984 Error_Node => Subtype_Indication (Type_Definition (N)));
9987 Iface := First (Interface_List (Def));
9988 while Present (Iface) loop
9989 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9991 Parent_Node := Parent (Base_Type (Iface_Typ));
9992 Iface_Def := Type_Definition (Parent_Node);
9994 if not Is_Interface (Iface_Typ) then
9995 Diagnose_Interface (Iface, Iface_Typ);
9998 -- "The declaration of a specific descendant of an interface
9999 -- type freezes the interface type" RM 13.14
10001 Freeze_Before (N, Iface_Typ);
10002 Check_Ifaces (Iface_Def, Error_Node => Iface);
10008 if Is_Task and Is_Protected then
10010 ("type cannot derive from task and protected interface", N);
10012 end Check_Interfaces;
10014 ------------------------------------
10015 -- Check_Or_Process_Discriminants --
10016 ------------------------------------
10018 -- If an incomplete or private type declaration was already given for the
10019 -- type, the discriminants may have already been processed if they were
10020 -- present on the incomplete declaration. In this case a full conformance
10021 -- check has been performed in Find_Type_Name, and we then recheck here
10022 -- some properties that can't be checked on the partial view alone.
10023 -- Otherwise we call Process_Discriminants.
10025 procedure Check_Or_Process_Discriminants
10028 Prev : Entity_Id := Empty)
10031 if Has_Discriminants (T) then
10033 -- Discriminants are already set on T if they were already present
10034 -- on the partial view. Make them visible to component declarations.
10038 -- Discriminant on T (full view) referencing expr on partial view
10040 Prev_D : Entity_Id;
10041 -- Entity of corresponding discriminant on partial view
10044 -- Discriminant specification for full view, expression is the
10045 -- syntactic copy on full view (which has been checked for
10046 -- conformance with partial view), only used here to post error
10050 D := First_Discriminant (T);
10051 New_D := First (Discriminant_Specifications (N));
10052 while Present (D) loop
10053 Prev_D := Current_Entity (D);
10054 Set_Current_Entity (D);
10055 Set_Is_Immediately_Visible (D);
10056 Set_Homonym (D, Prev_D);
10058 -- Handle the case where there is an untagged partial view and
10059 -- the full view is tagged: must disallow discriminants with
10060 -- defaults, unless compiling for Ada 2012, which allows a
10061 -- limited tagged type to have defaulted discriminants (see
10062 -- AI05-0214). However, suppress the error here if it was
10063 -- already reported on the default expression of the partial
10066 if Is_Tagged_Type (T)
10067 and then Present (Expression (Parent (D)))
10068 and then (not Is_Limited_Type (Current_Scope)
10069 or else Ada_Version < Ada_2012)
10070 and then not Error_Posted (Expression (Parent (D)))
10072 if Ada_Version >= Ada_2012 then
10074 ("discriminants of nonlimited tagged type cannot have"
10076 Expression (New_D));
10079 ("discriminants of tagged type cannot have defaults",
10080 Expression (New_D));
10084 -- Ada 2005 (AI-230): Access discriminant allowed in
10085 -- non-limited record types.
10087 if Ada_Version < Ada_2005 then
10089 -- This restriction gets applied to the full type here. It
10090 -- has already been applied earlier to the partial view.
10092 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
10095 Next_Discriminant (D);
10100 elsif Present (Discriminant_Specifications (N)) then
10101 Process_Discriminants (N, Prev);
10103 end Check_Or_Process_Discriminants;
10105 ----------------------
10106 -- Check_Real_Bound --
10107 ----------------------
10109 procedure Check_Real_Bound (Bound : Node_Id) is
10111 if not Is_Real_Type (Etype (Bound)) then
10113 ("bound in real type definition must be of real type", Bound);
10115 elsif not Is_OK_Static_Expression (Bound) then
10116 Flag_Non_Static_Expr
10117 ("non-static expression used for real type bound!", Bound);
10124 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
10126 Resolve (Bound, Standard_Float);
10127 end Check_Real_Bound;
10129 ------------------------------
10130 -- Complete_Private_Subtype --
10131 ------------------------------
10133 procedure Complete_Private_Subtype
10136 Full_Base : Entity_Id;
10137 Related_Nod : Node_Id)
10139 Save_Next_Entity : Entity_Id;
10140 Save_Homonym : Entity_Id;
10143 -- Set semantic attributes for (implicit) private subtype completion.
10144 -- If the full type has no discriminants, then it is a copy of the full
10145 -- view of the base. Otherwise, it is a subtype of the base with a
10146 -- possible discriminant constraint. Save and restore the original
10147 -- Next_Entity field of full to ensure that the calls to Copy_Node
10148 -- do not corrupt the entity chain.
10150 -- Note that the type of the full view is the same entity as the type of
10151 -- the partial view. In this fashion, the subtype has access to the
10152 -- correct view of the parent.
10154 Save_Next_Entity := Next_Entity (Full);
10155 Save_Homonym := Homonym (Priv);
10157 case Ekind (Full_Base) is
10158 when E_Record_Type |
10164 Copy_Node (Priv, Full);
10166 Set_Has_Discriminants (Full, Has_Discriminants (Full_Base));
10167 Set_First_Entity (Full, First_Entity (Full_Base));
10168 Set_Last_Entity (Full, Last_Entity (Full_Base));
10171 Copy_Node (Full_Base, Full);
10172 Set_Chars (Full, Chars (Priv));
10173 Conditional_Delay (Full, Priv);
10174 Set_Sloc (Full, Sloc (Priv));
10177 Set_Next_Entity (Full, Save_Next_Entity);
10178 Set_Homonym (Full, Save_Homonym);
10179 Set_Associated_Node_For_Itype (Full, Related_Nod);
10181 -- Set common attributes for all subtypes: kind, convention, etc.
10183 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
10184 Set_Convention (Full, Convention (Full_Base));
10186 -- The Etype of the full view is inconsistent. Gigi needs to see the
10187 -- structural full view, which is what the current scheme gives:
10188 -- the Etype of the full view is the etype of the full base. However,
10189 -- if the full base is a derived type, the full view then looks like
10190 -- a subtype of the parent, not a subtype of the full base. If instead
10193 -- Set_Etype (Full, Full_Base);
10195 -- then we get inconsistencies in the front-end (confusion between
10196 -- views). Several outstanding bugs are related to this ???
10198 Set_Is_First_Subtype (Full, False);
10199 Set_Scope (Full, Scope (Priv));
10200 Set_Size_Info (Full, Full_Base);
10201 Set_RM_Size (Full, RM_Size (Full_Base));
10202 Set_Is_Itype (Full);
10204 -- A subtype of a private-type-without-discriminants, whose full-view
10205 -- has discriminants with default expressions, is not constrained!
10207 if not Has_Discriminants (Priv) then
10208 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
10210 if Has_Discriminants (Full_Base) then
10211 Set_Discriminant_Constraint
10212 (Full, Discriminant_Constraint (Full_Base));
10214 -- The partial view may have been indefinite, the full view
10217 Set_Has_Unknown_Discriminants
10218 (Full, Has_Unknown_Discriminants (Full_Base));
10222 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
10223 Set_Depends_On_Private (Full, Has_Private_Component (Full));
10225 -- Freeze the private subtype entity if its parent is delayed, and not
10226 -- already frozen. We skip this processing if the type is an anonymous
10227 -- subtype of a record component, or is the corresponding record of a
10228 -- protected type, since ???
10230 if not Is_Type (Scope (Full)) then
10231 Set_Has_Delayed_Freeze (Full,
10232 Has_Delayed_Freeze (Full_Base)
10233 and then (not Is_Frozen (Full_Base)));
10236 Set_Freeze_Node (Full, Empty);
10237 Set_Is_Frozen (Full, False);
10238 Set_Full_View (Priv, Full);
10240 if Has_Discriminants (Full) then
10241 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
10242 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
10244 if Has_Unknown_Discriminants (Full) then
10245 Set_Discriminant_Constraint (Full, No_Elist);
10249 if Ekind (Full_Base) = E_Record_Type
10250 and then Has_Discriminants (Full_Base)
10251 and then Has_Discriminants (Priv) -- might not, if errors
10252 and then not Has_Unknown_Discriminants (Priv)
10253 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
10255 Create_Constrained_Components
10256 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
10258 -- If the full base is itself derived from private, build a congruent
10259 -- subtype of its underlying type, for use by the back end. For a
10260 -- constrained record component, the declaration cannot be placed on
10261 -- the component list, but it must nevertheless be built an analyzed, to
10262 -- supply enough information for Gigi to compute the size of component.
10264 elsif Ekind (Full_Base) in Private_Kind
10265 and then Is_Derived_Type (Full_Base)
10266 and then Has_Discriminants (Full_Base)
10267 and then (Ekind (Current_Scope) /= E_Record_Subtype)
10269 if not Is_Itype (Priv)
10271 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
10273 Build_Underlying_Full_View
10274 (Parent (Priv), Full, Etype (Full_Base));
10276 elsif Nkind (Related_Nod) = N_Component_Declaration then
10277 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
10280 elsif Is_Record_Type (Full_Base) then
10282 -- Show Full is simply a renaming of Full_Base
10284 Set_Cloned_Subtype (Full, Full_Base);
10287 -- It is unsafe to share to bounds of a scalar type, because the Itype
10288 -- is elaborated on demand, and if a bound is non-static then different
10289 -- orders of elaboration in different units will lead to different
10290 -- external symbols.
10292 if Is_Scalar_Type (Full_Base) then
10293 Set_Scalar_Range (Full,
10294 Make_Range (Sloc (Related_Nod),
10296 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
10298 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
10300 -- This completion inherits the bounds of the full parent, but if
10301 -- the parent is an unconstrained floating point type, so is the
10304 if Is_Floating_Point_Type (Full_Base) then
10305 Set_Includes_Infinities
10306 (Scalar_Range (Full), Has_Infinities (Full_Base));
10310 -- ??? It seems that a lot of fields are missing that should be copied
10311 -- from Full_Base to Full. Here are some that are introduced in a
10312 -- non-disruptive way but a cleanup is necessary.
10314 if Is_Tagged_Type (Full_Base) then
10315 Set_Is_Tagged_Type (Full);
10316 Set_Direct_Primitive_Operations (Full,
10317 Direct_Primitive_Operations (Full_Base));
10319 -- Inherit class_wide type of full_base in case the partial view was
10320 -- not tagged. Otherwise it has already been created when the private
10321 -- subtype was analyzed.
10323 if No (Class_Wide_Type (Full)) then
10324 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
10327 -- If this is a subtype of a protected or task type, constrain its
10328 -- corresponding record, unless this is a subtype without constraints,
10329 -- i.e. a simple renaming as with an actual subtype in an instance.
10331 elsif Is_Concurrent_Type (Full_Base) then
10332 if Has_Discriminants (Full)
10333 and then Present (Corresponding_Record_Type (Full_Base))
10335 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
10337 Set_Corresponding_Record_Type (Full,
10338 Constrain_Corresponding_Record
10339 (Full, Corresponding_Record_Type (Full_Base),
10340 Related_Nod, Full_Base));
10343 Set_Corresponding_Record_Type (Full,
10344 Corresponding_Record_Type (Full_Base));
10348 -- Link rep item chain, and also setting of Has_Predicates from private
10349 -- subtype to full subtype, since we will need these on the full subtype
10350 -- to create the predicate function. Note that the full subtype may
10351 -- already have rep items, inherited from the full view of the base
10352 -- type, so we must be sure not to overwrite these entries.
10357 Next_Item : Node_Id;
10360 Item := First_Rep_Item (Full);
10362 -- If no existing rep items on full type, we can just link directly
10363 -- to the list of items on the private type.
10366 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
10368 -- Otherwise, search to the end of items currently linked to the full
10369 -- subtype and append the private items to the end. However, if Priv
10370 -- and Full already have the same list of rep items, then the append
10371 -- is not done, as that would create a circularity.
10373 elsif Item /= First_Rep_Item (Priv) then
10377 Next_Item := Next_Rep_Item (Item);
10378 exit when No (Next_Item);
10381 -- If the private view has aspect specifications, the full view
10382 -- inherits them. Since these aspects may already have been
10383 -- attached to the full view during derivation, do not append
10384 -- them if already present.
10386 if Item = First_Rep_Item (Priv) then
10392 -- And link the private type items at the end of the chain
10395 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
10400 -- Make sure Has_Predicates is set on full type if it is set on the
10401 -- private type. Note that it may already be set on the full type and
10402 -- if so, we don't want to unset it.
10404 if Has_Predicates (Priv) then
10405 Set_Has_Predicates (Full);
10407 end Complete_Private_Subtype;
10409 ----------------------------
10410 -- Constant_Redeclaration --
10411 ----------------------------
10413 procedure Constant_Redeclaration
10418 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
10419 Obj_Def : constant Node_Id := Object_Definition (N);
10422 procedure Check_Possible_Deferred_Completion
10423 (Prev_Id : Entity_Id;
10424 Prev_Obj_Def : Node_Id;
10425 Curr_Obj_Def : Node_Id);
10426 -- Determine whether the two object definitions describe the partial
10427 -- and the full view of a constrained deferred constant. Generate
10428 -- a subtype for the full view and verify that it statically matches
10429 -- the subtype of the partial view.
10431 procedure Check_Recursive_Declaration (Typ : Entity_Id);
10432 -- If deferred constant is an access type initialized with an allocator,
10433 -- check whether there is an illegal recursion in the definition,
10434 -- through a default value of some record subcomponent. This is normally
10435 -- detected when generating init procs, but requires this additional
10436 -- mechanism when expansion is disabled.
10438 ----------------------------------------
10439 -- Check_Possible_Deferred_Completion --
10440 ----------------------------------------
10442 procedure Check_Possible_Deferred_Completion
10443 (Prev_Id : Entity_Id;
10444 Prev_Obj_Def : Node_Id;
10445 Curr_Obj_Def : Node_Id)
10448 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
10449 and then Present (Constraint (Prev_Obj_Def))
10450 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
10451 and then Present (Constraint (Curr_Obj_Def))
10454 Loc : constant Source_Ptr := Sloc (N);
10455 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
10456 Decl : constant Node_Id :=
10457 Make_Subtype_Declaration (Loc,
10458 Defining_Identifier => Def_Id,
10459 Subtype_Indication =>
10460 Relocate_Node (Curr_Obj_Def));
10463 Insert_Before_And_Analyze (N, Decl);
10464 Set_Etype (Id, Def_Id);
10466 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
10467 Error_Msg_Sloc := Sloc (Prev_Id);
10468 Error_Msg_N ("subtype does not statically match deferred " &
10469 "declaration#", N);
10473 end Check_Possible_Deferred_Completion;
10475 ---------------------------------
10476 -- Check_Recursive_Declaration --
10477 ---------------------------------
10479 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
10483 if Is_Record_Type (Typ) then
10484 Comp := First_Component (Typ);
10485 while Present (Comp) loop
10486 if Comes_From_Source (Comp) then
10487 if Present (Expression (Parent (Comp)))
10488 and then Is_Entity_Name (Expression (Parent (Comp)))
10489 and then Entity (Expression (Parent (Comp))) = Prev
10491 Error_Msg_Sloc := Sloc (Parent (Comp));
10493 ("illegal circularity with declaration for&#",
10497 elsif Is_Record_Type (Etype (Comp)) then
10498 Check_Recursive_Declaration (Etype (Comp));
10502 Next_Component (Comp);
10505 end Check_Recursive_Declaration;
10507 -- Start of processing for Constant_Redeclaration
10510 if Nkind (Parent (Prev)) = N_Object_Declaration then
10511 if Nkind (Object_Definition
10512 (Parent (Prev))) = N_Subtype_Indication
10514 -- Find type of new declaration. The constraints of the two
10515 -- views must match statically, but there is no point in
10516 -- creating an itype for the full view.
10518 if Nkind (Obj_Def) = N_Subtype_Indication then
10519 Find_Type (Subtype_Mark (Obj_Def));
10520 New_T := Entity (Subtype_Mark (Obj_Def));
10523 Find_Type (Obj_Def);
10524 New_T := Entity (Obj_Def);
10530 -- The full view may impose a constraint, even if the partial
10531 -- view does not, so construct the subtype.
10533 New_T := Find_Type_Of_Object (Obj_Def, N);
10538 -- Current declaration is illegal, diagnosed below in Enter_Name
10544 -- If previous full declaration or a renaming declaration exists, or if
10545 -- a homograph is present, let Enter_Name handle it, either with an
10546 -- error or with the removal of an overridden implicit subprogram.
10548 if Ekind (Prev) /= E_Constant
10549 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
10550 or else Present (Expression (Parent (Prev)))
10551 or else Present (Full_View (Prev))
10555 -- Verify that types of both declarations match, or else that both types
10556 -- are anonymous access types whose designated subtypes statically match
10557 -- (as allowed in Ada 2005 by AI-385).
10559 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
10561 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
10562 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
10563 or else Is_Access_Constant (Etype (New_T)) /=
10564 Is_Access_Constant (Etype (Prev))
10565 or else Can_Never_Be_Null (Etype (New_T)) /=
10566 Can_Never_Be_Null (Etype (Prev))
10567 or else Null_Exclusion_Present (Parent (Prev)) /=
10568 Null_Exclusion_Present (Parent (Id))
10569 or else not Subtypes_Statically_Match
10570 (Designated_Type (Etype (Prev)),
10571 Designated_Type (Etype (New_T))))
10573 Error_Msg_Sloc := Sloc (Prev);
10574 Error_Msg_N ("type does not match declaration#", N);
10575 Set_Full_View (Prev, Id);
10576 Set_Etype (Id, Any_Type);
10579 Null_Exclusion_Present (Parent (Prev))
10580 and then not Null_Exclusion_Present (N)
10582 Error_Msg_Sloc := Sloc (Prev);
10583 Error_Msg_N ("null-exclusion does not match declaration#", N);
10584 Set_Full_View (Prev, Id);
10585 Set_Etype (Id, Any_Type);
10587 -- If so, process the full constant declaration
10590 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
10591 -- the deferred declaration is constrained, then the subtype defined
10592 -- by the subtype_indication in the full declaration shall match it
10595 Check_Possible_Deferred_Completion
10597 Prev_Obj_Def => Object_Definition (Parent (Prev)),
10598 Curr_Obj_Def => Obj_Def);
10600 Set_Full_View (Prev, Id);
10601 Set_Is_Public (Id, Is_Public (Prev));
10602 Set_Is_Internal (Id);
10603 Append_Entity (Id, Current_Scope);
10605 -- Check ALIASED present if present before (RM 7.4(7))
10607 if Is_Aliased (Prev)
10608 and then not Aliased_Present (N)
10610 Error_Msg_Sloc := Sloc (Prev);
10611 Error_Msg_N ("ALIASED required (see declaration#)", N);
10614 -- Check that placement is in private part and that the incomplete
10615 -- declaration appeared in the visible part.
10617 if Ekind (Current_Scope) = E_Package
10618 and then not In_Private_Part (Current_Scope)
10620 Error_Msg_Sloc := Sloc (Prev);
10622 ("full constant for declaration#"
10623 & " must be in private part", N);
10625 elsif Ekind (Current_Scope) = E_Package
10627 List_Containing (Parent (Prev)) /=
10628 Visible_Declarations
10629 (Specification (Unit_Declaration_Node (Current_Scope)))
10632 ("deferred constant must be declared in visible part",
10636 if Is_Access_Type (T)
10637 and then Nkind (Expression (N)) = N_Allocator
10639 Check_Recursive_Declaration (Designated_Type (T));
10642 end Constant_Redeclaration;
10644 ----------------------
10645 -- Constrain_Access --
10646 ----------------------
10648 procedure Constrain_Access
10649 (Def_Id : in out Entity_Id;
10651 Related_Nod : Node_Id)
10653 T : constant Entity_Id := Entity (Subtype_Mark (S));
10654 Desig_Type : constant Entity_Id := Designated_Type (T);
10655 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
10656 Constraint_OK : Boolean := True;
10658 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean;
10659 -- Simple predicate to test for defaulted discriminants
10660 -- Shouldn't this be in sem_util???
10662 ---------------------------------
10663 -- Has_Defaulted_Discriminants --
10664 ---------------------------------
10666 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean is
10668 return Has_Discriminants (Typ)
10669 and then Present (First_Discriminant (Typ))
10671 (Discriminant_Default_Value (First_Discriminant (Typ)));
10672 end Has_Defaulted_Discriminants;
10674 -- Start of processing for Constrain_Access
10677 if Is_Array_Type (Desig_Type) then
10678 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
10680 elsif (Is_Record_Type (Desig_Type)
10681 or else Is_Incomplete_Or_Private_Type (Desig_Type))
10682 and then not Is_Constrained (Desig_Type)
10684 -- ??? The following code is a temporary kludge to ignore a
10685 -- discriminant constraint on access type if it is constraining
10686 -- the current record. Avoid creating the implicit subtype of the
10687 -- record we are currently compiling since right now, we cannot
10688 -- handle these. For now, just return the access type itself.
10690 if Desig_Type = Current_Scope
10691 and then No (Def_Id)
10693 Set_Ekind (Desig_Subtype, E_Record_Subtype);
10694 Def_Id := Entity (Subtype_Mark (S));
10696 -- This call added to ensure that the constraint is analyzed
10697 -- (needed for a B test). Note that we still return early from
10698 -- this procedure to avoid recursive processing. ???
10700 Constrain_Discriminated_Type
10701 (Desig_Subtype, S, Related_Nod, For_Access => True);
10705 -- Enforce rule that the constraint is illegal if there is an
10706 -- unconstrained view of the designated type. This means that the
10707 -- partial view (either a private type declaration or a derivation
10708 -- from a private type) has no discriminants. (Defect Report
10709 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
10711 -- Rule updated for Ada 2005: the private type is said to have
10712 -- a constrained partial view, given that objects of the type
10713 -- can be declared. Furthermore, the rule applies to all access
10714 -- types, unlike the rule concerning default discriminants (see
10717 if (Ekind (T) = E_General_Access_Type
10718 or else Ada_Version >= Ada_2005)
10719 and then Has_Private_Declaration (Desig_Type)
10720 and then In_Open_Scopes (Scope (Desig_Type))
10721 and then Has_Discriminants (Desig_Type)
10724 Pack : constant Node_Id :=
10725 Unit_Declaration_Node (Scope (Desig_Type));
10730 if Nkind (Pack) = N_Package_Declaration then
10731 Decls := Visible_Declarations (Specification (Pack));
10732 Decl := First (Decls);
10733 while Present (Decl) loop
10734 if (Nkind (Decl) = N_Private_Type_Declaration
10736 Chars (Defining_Identifier (Decl)) =
10737 Chars (Desig_Type))
10740 (Nkind (Decl) = N_Full_Type_Declaration
10742 Chars (Defining_Identifier (Decl)) =
10744 and then Is_Derived_Type (Desig_Type)
10746 Has_Private_Declaration (Etype (Desig_Type)))
10748 if No (Discriminant_Specifications (Decl)) then
10750 ("cannot constrain access type if designated " &
10751 "type has constrained partial view", S);
10763 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
10764 For_Access => True);
10766 elsif (Is_Task_Type (Desig_Type)
10767 or else Is_Protected_Type (Desig_Type))
10768 and then not Is_Constrained (Desig_Type)
10770 Constrain_Concurrent
10771 (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
10774 Error_Msg_N ("invalid constraint on access type", S);
10775 Desig_Subtype := Desig_Type; -- Ignore invalid constraint.
10776 Constraint_OK := False;
10779 if No (Def_Id) then
10780 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
10782 Set_Ekind (Def_Id, E_Access_Subtype);
10785 if Constraint_OK then
10786 Set_Etype (Def_Id, Base_Type (T));
10788 if Is_Private_Type (Desig_Type) then
10789 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
10792 Set_Etype (Def_Id, Any_Type);
10795 Set_Size_Info (Def_Id, T);
10796 Set_Is_Constrained (Def_Id, Constraint_OK);
10797 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
10798 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10799 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
10801 Conditional_Delay (Def_Id, T);
10803 -- AI-363 : Subtypes of general access types whose designated types have
10804 -- default discriminants are disallowed. In instances, the rule has to
10805 -- be checked against the actual, of which T is the subtype. In a
10806 -- generic body, the rule is checked assuming that the actual type has
10807 -- defaulted discriminants.
10809 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
10810 if Ekind (Base_Type (T)) = E_General_Access_Type
10811 and then Has_Defaulted_Discriminants (Desig_Type)
10813 if Ada_Version < Ada_2005 then
10815 ("access subtype of general access type would not " &
10816 "be allowed in Ada 2005?", S);
10819 ("access subtype of general access type not allowed", S);
10822 Error_Msg_N ("\discriminants have defaults", S);
10824 elsif Is_Access_Type (T)
10825 and then Is_Generic_Type (Desig_Type)
10826 and then Has_Discriminants (Desig_Type)
10827 and then In_Package_Body (Current_Scope)
10829 if Ada_Version < Ada_2005 then
10831 ("access subtype would not be allowed in generic body " &
10832 "in Ada 2005?", S);
10835 ("access subtype not allowed in generic body", S);
10839 ("\designated type is a discriminated formal", S);
10842 end Constrain_Access;
10844 ---------------------
10845 -- Constrain_Array --
10846 ---------------------
10848 procedure Constrain_Array
10849 (Def_Id : in out Entity_Id;
10851 Related_Nod : Node_Id;
10852 Related_Id : Entity_Id;
10853 Suffix : Character)
10855 C : constant Node_Id := Constraint (SI);
10856 Number_Of_Constraints : Nat := 0;
10859 Constraint_OK : Boolean := True;
10862 T := Entity (Subtype_Mark (SI));
10864 if Ekind (T) in Access_Kind then
10865 T := Designated_Type (T);
10868 -- If an index constraint follows a subtype mark in a subtype indication
10869 -- then the type or subtype denoted by the subtype mark must not already
10870 -- impose an index constraint. The subtype mark must denote either an
10871 -- unconstrained array type or an access type whose designated type
10872 -- is such an array type... (RM 3.6.1)
10874 if Is_Constrained (T) then
10875 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
10876 Constraint_OK := False;
10879 S := First (Constraints (C));
10880 while Present (S) loop
10881 Number_Of_Constraints := Number_Of_Constraints + 1;
10885 -- In either case, the index constraint must provide a discrete
10886 -- range for each index of the array type and the type of each
10887 -- discrete range must be the same as that of the corresponding
10888 -- index. (RM 3.6.1)
10890 if Number_Of_Constraints /= Number_Dimensions (T) then
10891 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
10892 Constraint_OK := False;
10895 S := First (Constraints (C));
10896 Index := First_Index (T);
10899 -- Apply constraints to each index type
10901 for J in 1 .. Number_Of_Constraints loop
10902 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
10910 if No (Def_Id) then
10912 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
10913 Set_Parent (Def_Id, Related_Nod);
10916 Set_Ekind (Def_Id, E_Array_Subtype);
10919 Set_Size_Info (Def_Id, (T));
10920 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10921 Set_Etype (Def_Id, Base_Type (T));
10923 if Constraint_OK then
10924 Set_First_Index (Def_Id, First (Constraints (C)));
10926 Set_First_Index (Def_Id, First_Index (T));
10929 Set_Is_Constrained (Def_Id, True);
10930 Set_Is_Aliased (Def_Id, Is_Aliased (T));
10931 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10933 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
10934 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
10936 -- A subtype does not inherit the packed_array_type of is parent. We
10937 -- need to initialize the attribute because if Def_Id is previously
10938 -- analyzed through a limited_with clause, it will have the attributes
10939 -- of an incomplete type, one of which is an Elist that overlaps the
10940 -- Packed_Array_Type field.
10942 Set_Packed_Array_Type (Def_Id, Empty);
10944 -- Build a freeze node if parent still needs one. Also make sure that
10945 -- the Depends_On_Private status is set because the subtype will need
10946 -- reprocessing at the time the base type does, and also we must set a
10947 -- conditional delay.
10949 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
10950 Conditional_Delay (Def_Id, T);
10951 end Constrain_Array;
10953 ------------------------------
10954 -- Constrain_Component_Type --
10955 ------------------------------
10957 function Constrain_Component_Type
10959 Constrained_Typ : Entity_Id;
10960 Related_Node : Node_Id;
10962 Constraints : Elist_Id) return Entity_Id
10964 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
10965 Compon_Type : constant Entity_Id := Etype (Comp);
10967 function Build_Constrained_Array_Type
10968 (Old_Type : Entity_Id) return Entity_Id;
10969 -- If Old_Type is an array type, one of whose indexes is constrained
10970 -- by a discriminant, build an Itype whose constraint replaces the
10971 -- discriminant with its value in the constraint.
10973 function Build_Constrained_Discriminated_Type
10974 (Old_Type : Entity_Id) return Entity_Id;
10975 -- Ditto for record components
10977 function Build_Constrained_Access_Type
10978 (Old_Type : Entity_Id) return Entity_Id;
10979 -- Ditto for access types. Makes use of previous two functions, to
10980 -- constrain designated type.
10982 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
10983 -- T is an array or discriminated type, C is a list of constraints
10984 -- that apply to T. This routine builds the constrained subtype.
10986 function Is_Discriminant (Expr : Node_Id) return Boolean;
10987 -- Returns True if Expr is a discriminant
10989 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
10990 -- Find the value of discriminant Discrim in Constraint
10992 -----------------------------------
10993 -- Build_Constrained_Access_Type --
10994 -----------------------------------
10996 function Build_Constrained_Access_Type
10997 (Old_Type : Entity_Id) return Entity_Id
10999 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
11001 Desig_Subtype : Entity_Id;
11005 -- if the original access type was not embedded in the enclosing
11006 -- type definition, there is no need to produce a new access
11007 -- subtype. In fact every access type with an explicit constraint
11008 -- generates an itype whose scope is the enclosing record.
11010 if not Is_Type (Scope (Old_Type)) then
11013 elsif Is_Array_Type (Desig_Type) then
11014 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
11016 elsif Has_Discriminants (Desig_Type) then
11018 -- This may be an access type to an enclosing record type for
11019 -- which we are constructing the constrained components. Return
11020 -- the enclosing record subtype. This is not always correct,
11021 -- but avoids infinite recursion. ???
11023 Desig_Subtype := Any_Type;
11025 for J in reverse 0 .. Scope_Stack.Last loop
11026 Scop := Scope_Stack.Table (J).Entity;
11029 and then Base_Type (Scop) = Base_Type (Desig_Type)
11031 Desig_Subtype := Scop;
11034 exit when not Is_Type (Scop);
11037 if Desig_Subtype = Any_Type then
11039 Build_Constrained_Discriminated_Type (Desig_Type);
11046 if Desig_Subtype /= Desig_Type then
11048 -- The Related_Node better be here or else we won't be able
11049 -- to attach new itypes to a node in the tree.
11051 pragma Assert (Present (Related_Node));
11053 Itype := Create_Itype (E_Access_Subtype, Related_Node);
11055 Set_Etype (Itype, Base_Type (Old_Type));
11056 Set_Size_Info (Itype, (Old_Type));
11057 Set_Directly_Designated_Type (Itype, Desig_Subtype);
11058 Set_Depends_On_Private (Itype, Has_Private_Component
11060 Set_Is_Access_Constant (Itype, Is_Access_Constant
11063 -- The new itype needs freezing when it depends on a not frozen
11064 -- type and the enclosing subtype needs freezing.
11066 if Has_Delayed_Freeze (Constrained_Typ)
11067 and then not Is_Frozen (Constrained_Typ)
11069 Conditional_Delay (Itype, Base_Type (Old_Type));
11077 end Build_Constrained_Access_Type;
11079 ----------------------------------
11080 -- Build_Constrained_Array_Type --
11081 ----------------------------------
11083 function Build_Constrained_Array_Type
11084 (Old_Type : Entity_Id) return Entity_Id
11088 Old_Index : Node_Id;
11089 Range_Node : Node_Id;
11090 Constr_List : List_Id;
11092 Need_To_Create_Itype : Boolean := False;
11095 Old_Index := First_Index (Old_Type);
11096 while Present (Old_Index) loop
11097 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
11099 if Is_Discriminant (Lo_Expr)
11100 or else Is_Discriminant (Hi_Expr)
11102 Need_To_Create_Itype := True;
11105 Next_Index (Old_Index);
11108 if Need_To_Create_Itype then
11109 Constr_List := New_List;
11111 Old_Index := First_Index (Old_Type);
11112 while Present (Old_Index) loop
11113 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
11115 if Is_Discriminant (Lo_Expr) then
11116 Lo_Expr := Get_Discr_Value (Lo_Expr);
11119 if Is_Discriminant (Hi_Expr) then
11120 Hi_Expr := Get_Discr_Value (Hi_Expr);
11125 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
11127 Append (Range_Node, To => Constr_List);
11129 Next_Index (Old_Index);
11132 return Build_Subtype (Old_Type, Constr_List);
11137 end Build_Constrained_Array_Type;
11139 ------------------------------------------
11140 -- Build_Constrained_Discriminated_Type --
11141 ------------------------------------------
11143 function Build_Constrained_Discriminated_Type
11144 (Old_Type : Entity_Id) return Entity_Id
11147 Constr_List : List_Id;
11148 Old_Constraint : Elmt_Id;
11150 Need_To_Create_Itype : Boolean := False;
11153 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
11154 while Present (Old_Constraint) loop
11155 Expr := Node (Old_Constraint);
11157 if Is_Discriminant (Expr) then
11158 Need_To_Create_Itype := True;
11161 Next_Elmt (Old_Constraint);
11164 if Need_To_Create_Itype then
11165 Constr_List := New_List;
11167 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
11168 while Present (Old_Constraint) loop
11169 Expr := Node (Old_Constraint);
11171 if Is_Discriminant (Expr) then
11172 Expr := Get_Discr_Value (Expr);
11175 Append (New_Copy_Tree (Expr), To => Constr_List);
11177 Next_Elmt (Old_Constraint);
11180 return Build_Subtype (Old_Type, Constr_List);
11185 end Build_Constrained_Discriminated_Type;
11187 -------------------
11188 -- Build_Subtype --
11189 -------------------
11191 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
11193 Subtyp_Decl : Node_Id;
11194 Def_Id : Entity_Id;
11195 Btyp : Entity_Id := Base_Type (T);
11198 -- The Related_Node better be here or else we won't be able to
11199 -- attach new itypes to a node in the tree.
11201 pragma Assert (Present (Related_Node));
11203 -- If the view of the component's type is incomplete or private
11204 -- with unknown discriminants, then the constraint must be applied
11205 -- to the full type.
11207 if Has_Unknown_Discriminants (Btyp)
11208 and then Present (Underlying_Type (Btyp))
11210 Btyp := Underlying_Type (Btyp);
11214 Make_Subtype_Indication (Loc,
11215 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
11216 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
11218 Def_Id := Create_Itype (Ekind (T), Related_Node);
11221 Make_Subtype_Declaration (Loc,
11222 Defining_Identifier => Def_Id,
11223 Subtype_Indication => Indic);
11225 Set_Parent (Subtyp_Decl, Parent (Related_Node));
11227 -- Itypes must be analyzed with checks off (see package Itypes)
11229 Analyze (Subtyp_Decl, Suppress => All_Checks);
11234 ---------------------
11235 -- Get_Discr_Value --
11236 ---------------------
11238 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
11243 -- The discriminant may be declared for the type, in which case we
11244 -- find it by iterating over the list of discriminants. If the
11245 -- discriminant is inherited from a parent type, it appears as the
11246 -- corresponding discriminant of the current type. This will be the
11247 -- case when constraining an inherited component whose constraint is
11248 -- given by a discriminant of the parent.
11250 D := First_Discriminant (Typ);
11251 E := First_Elmt (Constraints);
11253 while Present (D) loop
11254 if D = Entity (Discrim)
11255 or else D = CR_Discriminant (Entity (Discrim))
11256 or else Corresponding_Discriminant (D) = Entity (Discrim)
11261 Next_Discriminant (D);
11265 -- The Corresponding_Discriminant mechanism is incomplete, because
11266 -- the correspondence between new and old discriminants is not one
11267 -- to one: one new discriminant can constrain several old ones. In
11268 -- that case, scan sequentially the stored_constraint, the list of
11269 -- discriminants of the parents, and the constraints.
11270 -- Previous code checked for the present of the Stored_Constraint
11271 -- list for the derived type, but did not use it at all. Should it
11272 -- be present when the component is a discriminated task type?
11274 if Is_Derived_Type (Typ)
11275 and then Scope (Entity (Discrim)) = Etype (Typ)
11277 D := First_Discriminant (Etype (Typ));
11278 E := First_Elmt (Constraints);
11279 while Present (D) loop
11280 if D = Entity (Discrim) then
11284 Next_Discriminant (D);
11289 -- Something is wrong if we did not find the value
11291 raise Program_Error;
11292 end Get_Discr_Value;
11294 ---------------------
11295 -- Is_Discriminant --
11296 ---------------------
11298 function Is_Discriminant (Expr : Node_Id) return Boolean is
11299 Discrim_Scope : Entity_Id;
11302 if Denotes_Discriminant (Expr) then
11303 Discrim_Scope := Scope (Entity (Expr));
11305 -- Either we have a reference to one of Typ's discriminants,
11307 pragma Assert (Discrim_Scope = Typ
11309 -- or to the discriminants of the parent type, in the case
11310 -- of a derivation of a tagged type with variants.
11312 or else Discrim_Scope = Etype (Typ)
11313 or else Full_View (Discrim_Scope) = Etype (Typ)
11315 -- or same as above for the case where the discriminants
11316 -- were declared in Typ's private view.
11318 or else (Is_Private_Type (Discrim_Scope)
11319 and then Chars (Discrim_Scope) = Chars (Typ))
11321 -- or else we are deriving from the full view and the
11322 -- discriminant is declared in the private entity.
11324 or else (Is_Private_Type (Typ)
11325 and then Chars (Discrim_Scope) = Chars (Typ))
11327 -- Or we are constrained the corresponding record of a
11328 -- synchronized type that completes a private declaration.
11330 or else (Is_Concurrent_Record_Type (Typ)
11332 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
11334 -- or we have a class-wide type, in which case make sure the
11335 -- discriminant found belongs to the root type.
11337 or else (Is_Class_Wide_Type (Typ)
11338 and then Etype (Typ) = Discrim_Scope));
11343 -- In all other cases we have something wrong
11346 end Is_Discriminant;
11348 -- Start of processing for Constrain_Component_Type
11351 if Nkind (Parent (Comp)) = N_Component_Declaration
11352 and then Comes_From_Source (Parent (Comp))
11353 and then Comes_From_Source
11354 (Subtype_Indication (Component_Definition (Parent (Comp))))
11357 (Subtype_Indication (Component_Definition (Parent (Comp))))
11359 return Compon_Type;
11361 elsif Is_Array_Type (Compon_Type) then
11362 return Build_Constrained_Array_Type (Compon_Type);
11364 elsif Has_Discriminants (Compon_Type) then
11365 return Build_Constrained_Discriminated_Type (Compon_Type);
11367 elsif Is_Access_Type (Compon_Type) then
11368 return Build_Constrained_Access_Type (Compon_Type);
11371 return Compon_Type;
11373 end Constrain_Component_Type;
11375 --------------------------
11376 -- Constrain_Concurrent --
11377 --------------------------
11379 -- For concurrent types, the associated record value type carries the same
11380 -- discriminants, so when we constrain a concurrent type, we must constrain
11381 -- the corresponding record type as well.
11383 procedure Constrain_Concurrent
11384 (Def_Id : in out Entity_Id;
11386 Related_Nod : Node_Id;
11387 Related_Id : Entity_Id;
11388 Suffix : Character)
11390 -- Retrieve Base_Type to ensure getting to the concurrent type in the
11391 -- case of a private subtype (needed when only doing semantic analysis).
11393 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
11397 if Ekind (T_Ent) in Access_Kind then
11398 T_Ent := Designated_Type (T_Ent);
11401 T_Val := Corresponding_Record_Type (T_Ent);
11403 if Present (T_Val) then
11405 if No (Def_Id) then
11406 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
11409 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
11411 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
11412 Set_Corresponding_Record_Type (Def_Id,
11413 Constrain_Corresponding_Record
11414 (Def_Id, T_Val, Related_Nod, Related_Id));
11417 -- If there is no associated record, expansion is disabled and this
11418 -- is a generic context. Create a subtype in any case, so that
11419 -- semantic analysis can proceed.
11421 if No (Def_Id) then
11422 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
11425 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
11427 end Constrain_Concurrent;
11429 ------------------------------------
11430 -- Constrain_Corresponding_Record --
11431 ------------------------------------
11433 function Constrain_Corresponding_Record
11434 (Prot_Subt : Entity_Id;
11435 Corr_Rec : Entity_Id;
11436 Related_Nod : Node_Id;
11437 Related_Id : Entity_Id) return Entity_Id
11439 T_Sub : constant Entity_Id :=
11440 Create_Itype (E_Record_Subtype, Related_Nod, Related_Id, 'V');
11443 Set_Etype (T_Sub, Corr_Rec);
11444 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
11445 Set_Is_Constrained (T_Sub, True);
11446 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
11447 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
11449 -- As elsewhere, we do not want to create a freeze node for this itype
11450 -- if it is created for a constrained component of an enclosing record
11451 -- because references to outer discriminants will appear out of scope.
11453 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
11454 Conditional_Delay (T_Sub, Corr_Rec);
11456 Set_Is_Frozen (T_Sub);
11459 if Has_Discriminants (Prot_Subt) then -- False only if errors.
11460 Set_Discriminant_Constraint
11461 (T_Sub, Discriminant_Constraint (Prot_Subt));
11462 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
11463 Create_Constrained_Components
11464 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
11467 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
11470 end Constrain_Corresponding_Record;
11472 -----------------------
11473 -- Constrain_Decimal --
11474 -----------------------
11476 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
11477 T : constant Entity_Id := Entity (Subtype_Mark (S));
11478 C : constant Node_Id := Constraint (S);
11479 Loc : constant Source_Ptr := Sloc (C);
11480 Range_Expr : Node_Id;
11481 Digits_Expr : Node_Id;
11486 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
11488 if Nkind (C) = N_Range_Constraint then
11489 Range_Expr := Range_Expression (C);
11490 Digits_Val := Digits_Value (T);
11493 pragma Assert (Nkind (C) = N_Digits_Constraint);
11495 Check_SPARK_Restriction ("digits constraint is not allowed", S);
11497 Digits_Expr := Digits_Expression (C);
11498 Analyze_And_Resolve (Digits_Expr, Any_Integer);
11500 Check_Digits_Expression (Digits_Expr);
11501 Digits_Val := Expr_Value (Digits_Expr);
11503 if Digits_Val > Digits_Value (T) then
11505 ("digits expression is incompatible with subtype", C);
11506 Digits_Val := Digits_Value (T);
11509 if Present (Range_Constraint (C)) then
11510 Range_Expr := Range_Expression (Range_Constraint (C));
11512 Range_Expr := Empty;
11516 Set_Etype (Def_Id, Base_Type (T));
11517 Set_Size_Info (Def_Id, (T));
11518 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11519 Set_Delta_Value (Def_Id, Delta_Value (T));
11520 Set_Scale_Value (Def_Id, Scale_Value (T));
11521 Set_Small_Value (Def_Id, Small_Value (T));
11522 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
11523 Set_Digits_Value (Def_Id, Digits_Val);
11525 -- Manufacture range from given digits value if no range present
11527 if No (Range_Expr) then
11528 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
11532 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
11534 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
11537 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
11538 Set_Discrete_RM_Size (Def_Id);
11540 -- Unconditionally delay the freeze, since we cannot set size
11541 -- information in all cases correctly until the freeze point.
11543 Set_Has_Delayed_Freeze (Def_Id);
11544 end Constrain_Decimal;
11546 ----------------------------------
11547 -- Constrain_Discriminated_Type --
11548 ----------------------------------
11550 procedure Constrain_Discriminated_Type
11551 (Def_Id : Entity_Id;
11553 Related_Nod : Node_Id;
11554 For_Access : Boolean := False)
11556 E : constant Entity_Id := Entity (Subtype_Mark (S));
11559 Elist : Elist_Id := New_Elmt_List;
11561 procedure Fixup_Bad_Constraint;
11562 -- This is called after finding a bad constraint, and after having
11563 -- posted an appropriate error message. The mission is to leave the
11564 -- entity T in as reasonable state as possible!
11566 --------------------------
11567 -- Fixup_Bad_Constraint --
11568 --------------------------
11570 procedure Fixup_Bad_Constraint is
11572 -- Set a reasonable Ekind for the entity. For an incomplete type,
11573 -- we can't do much, but for other types, we can set the proper
11574 -- corresponding subtype kind.
11576 if Ekind (T) = E_Incomplete_Type then
11577 Set_Ekind (Def_Id, Ekind (T));
11579 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
11582 -- Set Etype to the known type, to reduce chances of cascaded errors
11584 Set_Etype (Def_Id, E);
11585 Set_Error_Posted (Def_Id);
11586 end Fixup_Bad_Constraint;
11588 -- Start of processing for Constrain_Discriminated_Type
11591 C := Constraint (S);
11593 -- A discriminant constraint is only allowed in a subtype indication,
11594 -- after a subtype mark. This subtype mark must denote either a type
11595 -- with discriminants, or an access type whose designated type is a
11596 -- type with discriminants. A discriminant constraint specifies the
11597 -- values of these discriminants (RM 3.7.2(5)).
11599 T := Base_Type (Entity (Subtype_Mark (S)));
11601 if Ekind (T) in Access_Kind then
11602 T := Designated_Type (T);
11605 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
11606 -- Avoid generating an error for access-to-incomplete subtypes.
11608 if Ada_Version >= Ada_2005
11609 and then Ekind (T) = E_Incomplete_Type
11610 and then Nkind (Parent (S)) = N_Subtype_Declaration
11611 and then not Is_Itype (Def_Id)
11613 -- A little sanity check, emit an error message if the type
11614 -- has discriminants to begin with. Type T may be a regular
11615 -- incomplete type or imported via a limited with clause.
11617 if Has_Discriminants (T)
11619 (From_With_Type (T)
11620 and then Present (Non_Limited_View (T))
11621 and then Nkind (Parent (Non_Limited_View (T))) =
11622 N_Full_Type_Declaration
11623 and then Present (Discriminant_Specifications
11624 (Parent (Non_Limited_View (T)))))
11627 ("(Ada 2005) incomplete subtype may not be constrained", C);
11629 Error_Msg_N ("invalid constraint: type has no discriminant", C);
11632 Fixup_Bad_Constraint;
11635 -- Check that the type has visible discriminants. The type may be
11636 -- a private type with unknown discriminants whose full view has
11637 -- discriminants which are invisible.
11639 elsif not Has_Discriminants (T)
11641 (Has_Unknown_Discriminants (T)
11642 and then Is_Private_Type (T))
11644 Error_Msg_N ("invalid constraint: type has no discriminant", C);
11645 Fixup_Bad_Constraint;
11648 elsif Is_Constrained (E)
11649 or else (Ekind (E) = E_Class_Wide_Subtype
11650 and then Present (Discriminant_Constraint (E)))
11652 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
11653 Fixup_Bad_Constraint;
11657 -- T may be an unconstrained subtype (e.g. a generic actual).
11658 -- Constraint applies to the base type.
11660 T := Base_Type (T);
11662 Elist := Build_Discriminant_Constraints (T, S);
11664 -- If the list returned was empty we had an error in building the
11665 -- discriminant constraint. We have also already signalled an error
11666 -- in the incomplete type case
11668 if Is_Empty_Elmt_List (Elist) then
11669 Fixup_Bad_Constraint;
11673 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
11674 end Constrain_Discriminated_Type;
11676 ---------------------------
11677 -- Constrain_Enumeration --
11678 ---------------------------
11680 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
11681 T : constant Entity_Id := Entity (Subtype_Mark (S));
11682 C : constant Node_Id := Constraint (S);
11685 Set_Ekind (Def_Id, E_Enumeration_Subtype);
11687 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
11689 Set_Etype (Def_Id, Base_Type (T));
11690 Set_Size_Info (Def_Id, (T));
11691 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11692 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
11694 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11696 Set_Discrete_RM_Size (Def_Id);
11697 end Constrain_Enumeration;
11699 ----------------------
11700 -- Constrain_Float --
11701 ----------------------
11703 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
11704 T : constant Entity_Id := Entity (Subtype_Mark (S));
11710 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
11712 Set_Etype (Def_Id, Base_Type (T));
11713 Set_Size_Info (Def_Id, (T));
11714 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11716 -- Process the constraint
11718 C := Constraint (S);
11720 -- Digits constraint present
11722 if Nkind (C) = N_Digits_Constraint then
11724 Check_SPARK_Restriction ("digits constraint is not allowed", S);
11725 Check_Restriction (No_Obsolescent_Features, C);
11727 if Warn_On_Obsolescent_Feature then
11729 ("subtype digits constraint is an " &
11730 "obsolescent feature (RM J.3(8))?", C);
11733 D := Digits_Expression (C);
11734 Analyze_And_Resolve (D, Any_Integer);
11735 Check_Digits_Expression (D);
11736 Set_Digits_Value (Def_Id, Expr_Value (D));
11738 -- Check that digits value is in range. Obviously we can do this
11739 -- at compile time, but it is strictly a runtime check, and of
11740 -- course there is an ACVC test that checks this!
11742 if Digits_Value (Def_Id) > Digits_Value (T) then
11743 Error_Msg_Uint_1 := Digits_Value (T);
11744 Error_Msg_N ("?digits value is too large, maximum is ^", D);
11746 Make_Raise_Constraint_Error (Sloc (D),
11747 Reason => CE_Range_Check_Failed);
11748 Insert_Action (Declaration_Node (Def_Id), Rais);
11751 C := Range_Constraint (C);
11753 -- No digits constraint present
11756 Set_Digits_Value (Def_Id, Digits_Value (T));
11759 -- Range constraint present
11761 if Nkind (C) = N_Range_Constraint then
11762 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11764 -- No range constraint present
11767 pragma Assert (No (C));
11768 Set_Scalar_Range (Def_Id, Scalar_Range (T));
11771 Set_Is_Constrained (Def_Id);
11772 end Constrain_Float;
11774 ---------------------
11775 -- Constrain_Index --
11776 ---------------------
11778 procedure Constrain_Index
11781 Related_Nod : Node_Id;
11782 Related_Id : Entity_Id;
11783 Suffix : Character;
11784 Suffix_Index : Nat)
11786 Def_Id : Entity_Id;
11787 R : Node_Id := Empty;
11788 T : constant Entity_Id := Etype (Index);
11791 if Nkind (S) = N_Range
11793 (Nkind (S) = N_Attribute_Reference
11794 and then Attribute_Name (S) = Name_Range)
11796 -- A Range attribute will be transformed into N_Range by Resolve
11802 Process_Range_Expr_In_Decl (R, T, Empty_List);
11804 if not Error_Posted (S)
11806 (Nkind (S) /= N_Range
11807 or else not Covers (T, (Etype (Low_Bound (S))))
11808 or else not Covers (T, (Etype (High_Bound (S)))))
11810 if Base_Type (T) /= Any_Type
11811 and then Etype (Low_Bound (S)) /= Any_Type
11812 and then Etype (High_Bound (S)) /= Any_Type
11814 Error_Msg_N ("range expected", S);
11818 elsif Nkind (S) = N_Subtype_Indication then
11820 -- The parser has verified that this is a discrete indication
11822 Resolve_Discrete_Subtype_Indication (S, T);
11823 R := Range_Expression (Constraint (S));
11825 -- Capture values of bounds and generate temporaries for them if
11826 -- needed, since checks may cause duplication of the expressions
11827 -- which must not be reevaluated.
11829 -- The forced evaluation removes side effects from expressions,
11830 -- which should occur also in Alfa mode. Otherwise, we end up with
11831 -- unexpected insertions of actions at places where this is not
11832 -- supposed to occur, e.g. on default parameters of a call.
11834 if Expander_Active then
11835 Force_Evaluation (Low_Bound (R));
11836 Force_Evaluation (High_Bound (R));
11839 elsif Nkind (S) = N_Discriminant_Association then
11841 -- Syntactically valid in subtype indication
11843 Error_Msg_N ("invalid index constraint", S);
11844 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11847 -- Subtype_Mark case, no anonymous subtypes to construct
11852 if Is_Entity_Name (S) then
11853 if not Is_Type (Entity (S)) then
11854 Error_Msg_N ("expect subtype mark for index constraint", S);
11856 elsif Base_Type (Entity (S)) /= Base_Type (T) then
11857 Wrong_Type (S, Base_Type (T));
11859 -- Check error of subtype with predicate in index constraint
11862 Bad_Predicated_Subtype_Use
11863 ("subtype& has predicate, not allowed in index constraint",
11870 Error_Msg_N ("invalid index constraint", S);
11871 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11877 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
11879 Set_Etype (Def_Id, Base_Type (T));
11881 if Is_Modular_Integer_Type (T) then
11882 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11884 elsif Is_Integer_Type (T) then
11885 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11888 Set_Ekind (Def_Id, E_Enumeration_Subtype);
11889 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
11890 Set_First_Literal (Def_Id, First_Literal (T));
11893 Set_Size_Info (Def_Id, (T));
11894 Set_RM_Size (Def_Id, RM_Size (T));
11895 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11897 Set_Scalar_Range (Def_Id, R);
11899 Set_Etype (S, Def_Id);
11900 Set_Discrete_RM_Size (Def_Id);
11901 end Constrain_Index;
11903 -----------------------
11904 -- Constrain_Integer --
11905 -----------------------
11907 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
11908 T : constant Entity_Id := Entity (Subtype_Mark (S));
11909 C : constant Node_Id := Constraint (S);
11912 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11914 if Is_Modular_Integer_Type (T) then
11915 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11917 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11920 Set_Etype (Def_Id, Base_Type (T));
11921 Set_Size_Info (Def_Id, (T));
11922 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11923 Set_Discrete_RM_Size (Def_Id);
11924 end Constrain_Integer;
11926 ------------------------------
11927 -- Constrain_Ordinary_Fixed --
11928 ------------------------------
11930 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
11931 T : constant Entity_Id := Entity (Subtype_Mark (S));
11937 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
11938 Set_Etype (Def_Id, Base_Type (T));
11939 Set_Size_Info (Def_Id, (T));
11940 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11941 Set_Small_Value (Def_Id, Small_Value (T));
11943 -- Process the constraint
11945 C := Constraint (S);
11947 -- Delta constraint present
11949 if Nkind (C) = N_Delta_Constraint then
11951 Check_SPARK_Restriction ("delta constraint is not allowed", S);
11952 Check_Restriction (No_Obsolescent_Features, C);
11954 if Warn_On_Obsolescent_Feature then
11956 ("subtype delta constraint is an " &
11957 "obsolescent feature (RM J.3(7))?");
11960 D := Delta_Expression (C);
11961 Analyze_And_Resolve (D, Any_Real);
11962 Check_Delta_Expression (D);
11963 Set_Delta_Value (Def_Id, Expr_Value_R (D));
11965 -- Check that delta value is in range. Obviously we can do this
11966 -- at compile time, but it is strictly a runtime check, and of
11967 -- course there is an ACVC test that checks this!
11969 if Delta_Value (Def_Id) < Delta_Value (T) then
11970 Error_Msg_N ("?delta value is too small", D);
11972 Make_Raise_Constraint_Error (Sloc (D),
11973 Reason => CE_Range_Check_Failed);
11974 Insert_Action (Declaration_Node (Def_Id), Rais);
11977 C := Range_Constraint (C);
11979 -- No delta constraint present
11982 Set_Delta_Value (Def_Id, Delta_Value (T));
11985 -- Range constraint present
11987 if Nkind (C) = N_Range_Constraint then
11988 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11990 -- No range constraint present
11993 pragma Assert (No (C));
11994 Set_Scalar_Range (Def_Id, Scalar_Range (T));
11998 Set_Discrete_RM_Size (Def_Id);
12000 -- Unconditionally delay the freeze, since we cannot set size
12001 -- information in all cases correctly until the freeze point.
12003 Set_Has_Delayed_Freeze (Def_Id);
12004 end Constrain_Ordinary_Fixed;
12006 -----------------------
12007 -- Contain_Interface --
12008 -----------------------
12010 function Contain_Interface
12011 (Iface : Entity_Id;
12012 Ifaces : Elist_Id) return Boolean
12014 Iface_Elmt : Elmt_Id;
12017 if Present (Ifaces) then
12018 Iface_Elmt := First_Elmt (Ifaces);
12019 while Present (Iface_Elmt) loop
12020 if Node (Iface_Elmt) = Iface then
12024 Next_Elmt (Iface_Elmt);
12029 end Contain_Interface;
12031 ---------------------------
12032 -- Convert_Scalar_Bounds --
12033 ---------------------------
12035 procedure Convert_Scalar_Bounds
12037 Parent_Type : Entity_Id;
12038 Derived_Type : Entity_Id;
12041 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
12048 -- Defend against previous errors
12050 if No (Scalar_Range (Derived_Type)) then
12054 Lo := Build_Scalar_Bound
12055 (Type_Low_Bound (Derived_Type),
12056 Parent_Type, Implicit_Base);
12058 Hi := Build_Scalar_Bound
12059 (Type_High_Bound (Derived_Type),
12060 Parent_Type, Implicit_Base);
12067 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
12069 Set_Parent (Rng, N);
12070 Set_Scalar_Range (Derived_Type, Rng);
12072 -- Analyze the bounds
12074 Analyze_And_Resolve (Lo, Implicit_Base);
12075 Analyze_And_Resolve (Hi, Implicit_Base);
12077 -- Analyze the range itself, except that we do not analyze it if
12078 -- the bounds are real literals, and we have a fixed-point type.
12079 -- The reason for this is that we delay setting the bounds in this
12080 -- case till we know the final Small and Size values (see circuit
12081 -- in Freeze.Freeze_Fixed_Point_Type for further details).
12083 if Is_Fixed_Point_Type (Parent_Type)
12084 and then Nkind (Lo) = N_Real_Literal
12085 and then Nkind (Hi) = N_Real_Literal
12089 -- Here we do the analysis of the range
12091 -- Note: we do this manually, since if we do a normal Analyze and
12092 -- Resolve call, there are problems with the conversions used for
12093 -- the derived type range.
12096 Set_Etype (Rng, Implicit_Base);
12097 Set_Analyzed (Rng, True);
12099 end Convert_Scalar_Bounds;
12101 -------------------
12102 -- Copy_And_Swap --
12103 -------------------
12105 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
12107 -- Initialize new full declaration entity by copying the pertinent
12108 -- fields of the corresponding private declaration entity.
12110 -- We temporarily set Ekind to a value appropriate for a type to
12111 -- avoid assert failures in Einfo from checking for setting type
12112 -- attributes on something that is not a type. Ekind (Priv) is an
12113 -- appropriate choice, since it allowed the attributes to be set
12114 -- in the first place. This Ekind value will be modified later.
12116 Set_Ekind (Full, Ekind (Priv));
12118 -- Also set Etype temporarily to Any_Type, again, in the absence
12119 -- of errors, it will be properly reset, and if there are errors,
12120 -- then we want a value of Any_Type to remain.
12122 Set_Etype (Full, Any_Type);
12124 -- Now start copying attributes
12126 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
12128 if Has_Discriminants (Full) then
12129 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
12130 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
12133 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
12134 Set_Homonym (Full, Homonym (Priv));
12135 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
12136 Set_Is_Public (Full, Is_Public (Priv));
12137 Set_Is_Pure (Full, Is_Pure (Priv));
12138 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
12139 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
12140 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
12141 Set_Has_Pragma_Unreferenced_Objects
12142 (Full, Has_Pragma_Unreferenced_Objects
12145 Conditional_Delay (Full, Priv);
12147 if Is_Tagged_Type (Full) then
12148 Set_Direct_Primitive_Operations (Full,
12149 Direct_Primitive_Operations (Priv));
12151 if Is_Base_Type (Priv) then
12152 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
12156 Set_Is_Volatile (Full, Is_Volatile (Priv));
12157 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
12158 Set_Scope (Full, Scope (Priv));
12159 Set_Next_Entity (Full, Next_Entity (Priv));
12160 Set_First_Entity (Full, First_Entity (Priv));
12161 Set_Last_Entity (Full, Last_Entity (Priv));
12163 -- If access types have been recorded for later handling, keep them in
12164 -- the full view so that they get handled when the full view freeze
12165 -- node is expanded.
12167 if Present (Freeze_Node (Priv))
12168 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
12170 Ensure_Freeze_Node (Full);
12171 Set_Access_Types_To_Process
12172 (Freeze_Node (Full),
12173 Access_Types_To_Process (Freeze_Node (Priv)));
12176 -- Swap the two entities. Now Private is the full type entity and Full
12177 -- is the private one. They will be swapped back at the end of the
12178 -- private part. This swapping ensures that the entity that is visible
12179 -- in the private part is the full declaration.
12181 Exchange_Entities (Priv, Full);
12182 Append_Entity (Full, Scope (Full));
12185 -------------------------------------
12186 -- Copy_Array_Base_Type_Attributes --
12187 -------------------------------------
12189 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
12191 Set_Component_Alignment (T1, Component_Alignment (T2));
12192 Set_Component_Type (T1, Component_Type (T2));
12193 Set_Component_Size (T1, Component_Size (T2));
12194 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
12195 Set_Finalize_Storage_Only (T1, Finalize_Storage_Only (T2));
12196 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
12197 Set_Has_Task (T1, Has_Task (T2));
12198 Set_Is_Packed (T1, Is_Packed (T2));
12199 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
12200 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
12201 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
12202 end Copy_Array_Base_Type_Attributes;
12204 -----------------------------------
12205 -- Copy_Array_Subtype_Attributes --
12206 -----------------------------------
12208 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
12210 Set_Size_Info (T1, T2);
12212 Set_First_Index (T1, First_Index (T2));
12213 Set_Is_Aliased (T1, Is_Aliased (T2));
12214 Set_Is_Atomic (T1, Is_Atomic (T2));
12215 Set_Is_Volatile (T1, Is_Volatile (T2));
12216 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
12217 Set_Is_Constrained (T1, Is_Constrained (T2));
12218 Set_Depends_On_Private (T1, Has_Private_Component (T2));
12219 Set_First_Rep_Item (T1, First_Rep_Item (T2));
12220 Set_Convention (T1, Convention (T2));
12221 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
12222 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
12223 Set_Packed_Array_Type (T1, Packed_Array_Type (T2));
12224 end Copy_Array_Subtype_Attributes;
12226 -----------------------------------
12227 -- Create_Constrained_Components --
12228 -----------------------------------
12230 procedure Create_Constrained_Components
12232 Decl_Node : Node_Id;
12234 Constraints : Elist_Id)
12236 Loc : constant Source_Ptr := Sloc (Subt);
12237 Comp_List : constant Elist_Id := New_Elmt_List;
12238 Parent_Type : constant Entity_Id := Etype (Typ);
12239 Assoc_List : constant List_Id := New_List;
12240 Discr_Val : Elmt_Id;
12244 Is_Static : Boolean := True;
12246 procedure Collect_Fixed_Components (Typ : Entity_Id);
12247 -- Collect parent type components that do not appear in a variant part
12249 procedure Create_All_Components;
12250 -- Iterate over Comp_List to create the components of the subtype
12252 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
12253 -- Creates a new component from Old_Compon, copying all the fields from
12254 -- it, including its Etype, inserts the new component in the Subt entity
12255 -- chain and returns the new component.
12257 function Is_Variant_Record (T : Entity_Id) return Boolean;
12258 -- If true, and discriminants are static, collect only components from
12259 -- variants selected by discriminant values.
12261 ------------------------------
12262 -- Collect_Fixed_Components --
12263 ------------------------------
12265 procedure Collect_Fixed_Components (Typ : Entity_Id) is
12267 -- Build association list for discriminants, and find components of the
12268 -- variant part selected by the values of the discriminants.
12270 Old_C := First_Discriminant (Typ);
12271 Discr_Val := First_Elmt (Constraints);
12272 while Present (Old_C) loop
12273 Append_To (Assoc_List,
12274 Make_Component_Association (Loc,
12275 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
12276 Expression => New_Copy (Node (Discr_Val))));
12278 Next_Elmt (Discr_Val);
12279 Next_Discriminant (Old_C);
12282 -- The tag and the possible parent component are unconditionally in
12285 if Is_Tagged_Type (Typ)
12286 or else Has_Controlled_Component (Typ)
12288 Old_C := First_Component (Typ);
12289 while Present (Old_C) loop
12290 if Chars ((Old_C)) = Name_uTag
12291 or else Chars ((Old_C)) = Name_uParent
12293 Append_Elmt (Old_C, Comp_List);
12296 Next_Component (Old_C);
12299 end Collect_Fixed_Components;
12301 ---------------------------
12302 -- Create_All_Components --
12303 ---------------------------
12305 procedure Create_All_Components is
12309 Comp := First_Elmt (Comp_List);
12310 while Present (Comp) loop
12311 Old_C := Node (Comp);
12312 New_C := Create_Component (Old_C);
12316 Constrain_Component_Type
12317 (Old_C, Subt, Decl_Node, Typ, Constraints));
12318 Set_Is_Public (New_C, Is_Public (Subt));
12322 end Create_All_Components;
12324 ----------------------
12325 -- Create_Component --
12326 ----------------------
12328 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
12329 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
12332 if Ekind (Old_Compon) = E_Discriminant
12333 and then Is_Completely_Hidden (Old_Compon)
12335 -- This is a shadow discriminant created for a discriminant of
12336 -- the parent type, which needs to be present in the subtype.
12337 -- Give the shadow discriminant an internal name that cannot
12338 -- conflict with that of visible components.
12340 Set_Chars (New_Compon, New_Internal_Name ('C'));
12343 -- Set the parent so we have a proper link for freezing etc. This is
12344 -- not a real parent pointer, since of course our parent does not own
12345 -- up to us and reference us, we are an illegitimate child of the
12346 -- original parent!
12348 Set_Parent (New_Compon, Parent (Old_Compon));
12350 -- If the old component's Esize was already determined and is a
12351 -- static value, then the new component simply inherits it. Otherwise
12352 -- the old component's size may require run-time determination, but
12353 -- the new component's size still might be statically determinable
12354 -- (if, for example it has a static constraint). In that case we want
12355 -- Layout_Type to recompute the component's size, so we reset its
12356 -- size and positional fields.
12358 if Frontend_Layout_On_Target
12359 and then not Known_Static_Esize (Old_Compon)
12361 Set_Esize (New_Compon, Uint_0);
12362 Init_Normalized_First_Bit (New_Compon);
12363 Init_Normalized_Position (New_Compon);
12364 Init_Normalized_Position_Max (New_Compon);
12367 -- We do not want this node marked as Comes_From_Source, since
12368 -- otherwise it would get first class status and a separate cross-
12369 -- reference line would be generated. Illegitimate children do not
12370 -- rate such recognition.
12372 Set_Comes_From_Source (New_Compon, False);
12374 -- But it is a real entity, and a birth certificate must be properly
12375 -- registered by entering it into the entity list.
12377 Enter_Name (New_Compon);
12380 end Create_Component;
12382 -----------------------
12383 -- Is_Variant_Record --
12384 -----------------------
12386 function Is_Variant_Record (T : Entity_Id) return Boolean is
12388 return Nkind (Parent (T)) = N_Full_Type_Declaration
12389 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
12390 and then Present (Component_List (Type_Definition (Parent (T))))
12393 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
12394 end Is_Variant_Record;
12396 -- Start of processing for Create_Constrained_Components
12399 pragma Assert (Subt /= Base_Type (Subt));
12400 pragma Assert (Typ = Base_Type (Typ));
12402 Set_First_Entity (Subt, Empty);
12403 Set_Last_Entity (Subt, Empty);
12405 -- Check whether constraint is fully static, in which case we can
12406 -- optimize the list of components.
12408 Discr_Val := First_Elmt (Constraints);
12409 while Present (Discr_Val) loop
12410 if not Is_OK_Static_Expression (Node (Discr_Val)) then
12411 Is_Static := False;
12415 Next_Elmt (Discr_Val);
12418 Set_Has_Static_Discriminants (Subt, Is_Static);
12422 -- Inherit the discriminants of the parent type
12424 Add_Discriminants : declare
12430 Old_C := First_Discriminant (Typ);
12432 while Present (Old_C) loop
12433 Num_Disc := Num_Disc + 1;
12434 New_C := Create_Component (Old_C);
12435 Set_Is_Public (New_C, Is_Public (Subt));
12436 Next_Discriminant (Old_C);
12439 -- For an untagged derived subtype, the number of discriminants may
12440 -- be smaller than the number of inherited discriminants, because
12441 -- several of them may be renamed by a single new discriminant or
12442 -- constrained. In this case, add the hidden discriminants back into
12443 -- the subtype, because they need to be present if the optimizer of
12444 -- the GCC 4.x back-end decides to break apart assignments between
12445 -- objects using the parent view into member-wise assignments.
12449 if Is_Derived_Type (Typ)
12450 and then not Is_Tagged_Type (Typ)
12452 Old_C := First_Stored_Discriminant (Typ);
12454 while Present (Old_C) loop
12455 Num_Gird := Num_Gird + 1;
12456 Next_Stored_Discriminant (Old_C);
12460 if Num_Gird > Num_Disc then
12462 -- Find out multiple uses of new discriminants, and add hidden
12463 -- components for the extra renamed discriminants. We recognize
12464 -- multiple uses through the Corresponding_Discriminant of a
12465 -- new discriminant: if it constrains several old discriminants,
12466 -- this field points to the last one in the parent type. The
12467 -- stored discriminants of the derived type have the same name
12468 -- as those of the parent.
12472 New_Discr : Entity_Id;
12473 Old_Discr : Entity_Id;
12476 Constr := First_Elmt (Stored_Constraint (Typ));
12477 Old_Discr := First_Stored_Discriminant (Typ);
12478 while Present (Constr) loop
12479 if Is_Entity_Name (Node (Constr))
12480 and then Ekind (Entity (Node (Constr))) = E_Discriminant
12482 New_Discr := Entity (Node (Constr));
12484 if Chars (Corresponding_Discriminant (New_Discr)) /=
12487 -- The new discriminant has been used to rename a
12488 -- subsequent old discriminant. Introduce a shadow
12489 -- component for the current old discriminant.
12491 New_C := Create_Component (Old_Discr);
12492 Set_Original_Record_Component (New_C, Old_Discr);
12496 -- The constraint has eliminated the old discriminant.
12497 -- Introduce a shadow component.
12499 New_C := Create_Component (Old_Discr);
12500 Set_Original_Record_Component (New_C, Old_Discr);
12503 Next_Elmt (Constr);
12504 Next_Stored_Discriminant (Old_Discr);
12508 end Add_Discriminants;
12511 and then Is_Variant_Record (Typ)
12513 Collect_Fixed_Components (Typ);
12515 Gather_Components (
12517 Component_List (Type_Definition (Parent (Typ))),
12518 Governed_By => Assoc_List,
12520 Report_Errors => Errors);
12521 pragma Assert (not Errors);
12523 Create_All_Components;
12525 -- If the subtype declaration is created for a tagged type derivation
12526 -- with constraints, we retrieve the record definition of the parent
12527 -- type to select the components of the proper variant.
12530 and then Is_Tagged_Type (Typ)
12531 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
12533 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
12534 and then Is_Variant_Record (Parent_Type)
12536 Collect_Fixed_Components (Typ);
12538 Gather_Components (
12540 Component_List (Type_Definition (Parent (Parent_Type))),
12541 Governed_By => Assoc_List,
12543 Report_Errors => Errors);
12544 pragma Assert (not Errors);
12546 -- If the tagged derivation has a type extension, collect all the
12547 -- new components therein.
12550 (Record_Extension_Part (Type_Definition (Parent (Typ))))
12552 Old_C := First_Component (Typ);
12553 while Present (Old_C) loop
12554 if Original_Record_Component (Old_C) = Old_C
12555 and then Chars (Old_C) /= Name_uTag
12556 and then Chars (Old_C) /= Name_uParent
12558 Append_Elmt (Old_C, Comp_List);
12561 Next_Component (Old_C);
12565 Create_All_Components;
12568 -- If discriminants are not static, or if this is a multi-level type
12569 -- extension, we have to include all components of the parent type.
12571 Old_C := First_Component (Typ);
12572 while Present (Old_C) loop
12573 New_C := Create_Component (Old_C);
12577 Constrain_Component_Type
12578 (Old_C, Subt, Decl_Node, Typ, Constraints));
12579 Set_Is_Public (New_C, Is_Public (Subt));
12581 Next_Component (Old_C);
12586 end Create_Constrained_Components;
12588 ------------------------------------------
12589 -- Decimal_Fixed_Point_Type_Declaration --
12590 ------------------------------------------
12592 procedure Decimal_Fixed_Point_Type_Declaration
12596 Loc : constant Source_Ptr := Sloc (Def);
12597 Digs_Expr : constant Node_Id := Digits_Expression (Def);
12598 Delta_Expr : constant Node_Id := Delta_Expression (Def);
12599 Implicit_Base : Entity_Id;
12606 Check_SPARK_Restriction
12607 ("decimal fixed point type is not allowed", Def);
12608 Check_Restriction (No_Fixed_Point, Def);
12610 -- Create implicit base type
12613 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
12614 Set_Etype (Implicit_Base, Implicit_Base);
12616 -- Analyze and process delta expression
12618 Analyze_And_Resolve (Delta_Expr, Universal_Real);
12620 Check_Delta_Expression (Delta_Expr);
12621 Delta_Val := Expr_Value_R (Delta_Expr);
12623 -- Check delta is power of 10, and determine scale value from it
12629 Scale_Val := Uint_0;
12632 if Val < Ureal_1 then
12633 while Val < Ureal_1 loop
12634 Val := Val * Ureal_10;
12635 Scale_Val := Scale_Val + 1;
12638 if Scale_Val > 18 then
12639 Error_Msg_N ("scale exceeds maximum value of 18", Def);
12640 Scale_Val := UI_From_Int (+18);
12644 while Val > Ureal_1 loop
12645 Val := Val / Ureal_10;
12646 Scale_Val := Scale_Val - 1;
12649 if Scale_Val < -18 then
12650 Error_Msg_N ("scale is less than minimum value of -18", Def);
12651 Scale_Val := UI_From_Int (-18);
12655 if Val /= Ureal_1 then
12656 Error_Msg_N ("delta expression must be a power of 10", Def);
12657 Delta_Val := Ureal_10 ** (-Scale_Val);
12661 -- Set delta, scale and small (small = delta for decimal type)
12663 Set_Delta_Value (Implicit_Base, Delta_Val);
12664 Set_Scale_Value (Implicit_Base, Scale_Val);
12665 Set_Small_Value (Implicit_Base, Delta_Val);
12667 -- Analyze and process digits expression
12669 Analyze_And_Resolve (Digs_Expr, Any_Integer);
12670 Check_Digits_Expression (Digs_Expr);
12671 Digs_Val := Expr_Value (Digs_Expr);
12673 if Digs_Val > 18 then
12674 Digs_Val := UI_From_Int (+18);
12675 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
12678 Set_Digits_Value (Implicit_Base, Digs_Val);
12679 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
12681 -- Set range of base type from digits value for now. This will be
12682 -- expanded to represent the true underlying base range by Freeze.
12684 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
12686 -- Note: We leave size as zero for now, size will be set at freeze
12687 -- time. We have to do this for ordinary fixed-point, because the size
12688 -- depends on the specified small, and we might as well do the same for
12689 -- decimal fixed-point.
12691 pragma Assert (Esize (Implicit_Base) = Uint_0);
12693 -- If there are bounds given in the declaration use them as the
12694 -- bounds of the first named subtype.
12696 if Present (Real_Range_Specification (Def)) then
12698 RRS : constant Node_Id := Real_Range_Specification (Def);
12699 Low : constant Node_Id := Low_Bound (RRS);
12700 High : constant Node_Id := High_Bound (RRS);
12705 Analyze_And_Resolve (Low, Any_Real);
12706 Analyze_And_Resolve (High, Any_Real);
12707 Check_Real_Bound (Low);
12708 Check_Real_Bound (High);
12709 Low_Val := Expr_Value_R (Low);
12710 High_Val := Expr_Value_R (High);
12712 if Low_Val < (-Bound_Val) then
12714 ("range low bound too small for digits value", Low);
12715 Low_Val := -Bound_Val;
12718 if High_Val > Bound_Val then
12720 ("range high bound too large for digits value", High);
12721 High_Val := Bound_Val;
12724 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
12727 -- If no explicit range, use range that corresponds to given
12728 -- digits value. This will end up as the final range for the
12732 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
12735 -- Complete entity for first subtype
12737 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
12738 Set_Etype (T, Implicit_Base);
12739 Set_Size_Info (T, Implicit_Base);
12740 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
12741 Set_Digits_Value (T, Digs_Val);
12742 Set_Delta_Value (T, Delta_Val);
12743 Set_Small_Value (T, Delta_Val);
12744 Set_Scale_Value (T, Scale_Val);
12745 Set_Is_Constrained (T);
12746 end Decimal_Fixed_Point_Type_Declaration;
12748 -----------------------------------
12749 -- Derive_Progenitor_Subprograms --
12750 -----------------------------------
12752 procedure Derive_Progenitor_Subprograms
12753 (Parent_Type : Entity_Id;
12754 Tagged_Type : Entity_Id)
12759 Iface_Elmt : Elmt_Id;
12760 Iface_Subp : Entity_Id;
12761 New_Subp : Entity_Id := Empty;
12762 Prim_Elmt : Elmt_Id;
12767 pragma Assert (Ada_Version >= Ada_2005
12768 and then Is_Record_Type (Tagged_Type)
12769 and then Is_Tagged_Type (Tagged_Type)
12770 and then Has_Interfaces (Tagged_Type));
12772 -- Step 1: Transfer to the full-view primitives associated with the
12773 -- partial-view that cover interface primitives. Conceptually this
12774 -- work should be done later by Process_Full_View; done here to
12775 -- simplify its implementation at later stages. It can be safely
12776 -- done here because interfaces must be visible in the partial and
12777 -- private view (RM 7.3(7.3/2)).
12779 -- Small optimization: This work is only required if the parent is
12780 -- abstract. If the tagged type is not abstract, it cannot have
12781 -- abstract primitives (the only entities in the list of primitives of
12782 -- non-abstract tagged types that can reference abstract primitives
12783 -- through its Alias attribute are the internal entities that have
12784 -- attribute Interface_Alias, and these entities are generated later
12785 -- by Add_Internal_Interface_Entities).
12787 if In_Private_Part (Current_Scope)
12788 and then Is_Abstract_Type (Parent_Type)
12790 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
12791 while Present (Elmt) loop
12792 Subp := Node (Elmt);
12794 -- At this stage it is not possible to have entities in the list
12795 -- of primitives that have attribute Interface_Alias
12797 pragma Assert (No (Interface_Alias (Subp)));
12799 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
12801 if Is_Interface (Typ) then
12802 E := Find_Primitive_Covering_Interface
12803 (Tagged_Type => Tagged_Type,
12804 Iface_Prim => Subp);
12807 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
12809 Replace_Elmt (Elmt, E);
12810 Remove_Homonym (Subp);
12818 -- Step 2: Add primitives of progenitors that are not implemented by
12819 -- parents of Tagged_Type
12821 if Present (Interfaces (Base_Type (Tagged_Type))) then
12822 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
12823 while Present (Iface_Elmt) loop
12824 Iface := Node (Iface_Elmt);
12826 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
12827 while Present (Prim_Elmt) loop
12828 Iface_Subp := Node (Prim_Elmt);
12830 -- Exclude derivation of predefined primitives except those
12831 -- that come from source, or are inherited from one that comes
12832 -- from source. Required to catch declarations of equality
12833 -- operators of interfaces. For example:
12835 -- type Iface is interface;
12836 -- function "=" (Left, Right : Iface) return Boolean;
12838 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
12839 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
12841 E := Find_Primitive_Covering_Interface
12842 (Tagged_Type => Tagged_Type,
12843 Iface_Prim => Iface_Subp);
12845 -- If not found we derive a new primitive leaving its alias
12846 -- attribute referencing the interface primitive
12850 (New_Subp, Iface_Subp, Tagged_Type, Iface);
12852 -- Ada 2012 (AI05-0197): If the covering primitive's name
12853 -- differs from the name of the interface primitive then it
12854 -- is a private primitive inherited from a parent type. In
12855 -- such case, given that Tagged_Type covers the interface,
12856 -- the inherited private primitive becomes visible. For such
12857 -- purpose we add a new entity that renames the inherited
12858 -- private primitive.
12860 elsif Chars (E) /= Chars (Iface_Subp) then
12861 pragma Assert (Has_Suffix (E, 'P'));
12863 (New_Subp, Iface_Subp, Tagged_Type, Iface);
12864 Set_Alias (New_Subp, E);
12865 Set_Is_Abstract_Subprogram (New_Subp,
12866 Is_Abstract_Subprogram (E));
12868 -- Propagate to the full view interface entities associated
12869 -- with the partial view
12871 elsif In_Private_Part (Current_Scope)
12872 and then Present (Alias (E))
12873 and then Alias (E) = Iface_Subp
12875 List_Containing (Parent (E)) /=
12876 Private_Declarations
12878 (Unit_Declaration_Node (Current_Scope)))
12880 Append_Elmt (E, Primitive_Operations (Tagged_Type));
12884 Next_Elmt (Prim_Elmt);
12887 Next_Elmt (Iface_Elmt);
12890 end Derive_Progenitor_Subprograms;
12892 -----------------------
12893 -- Derive_Subprogram --
12894 -----------------------
12896 procedure Derive_Subprogram
12897 (New_Subp : in out Entity_Id;
12898 Parent_Subp : Entity_Id;
12899 Derived_Type : Entity_Id;
12900 Parent_Type : Entity_Id;
12901 Actual_Subp : Entity_Id := Empty)
12903 Formal : Entity_Id;
12904 -- Formal parameter of parent primitive operation
12906 Formal_Of_Actual : Entity_Id;
12907 -- Formal parameter of actual operation, when the derivation is to
12908 -- create a renaming for a primitive operation of an actual in an
12911 New_Formal : Entity_Id;
12912 -- Formal of inherited operation
12914 Visible_Subp : Entity_Id := Parent_Subp;
12916 function Is_Private_Overriding return Boolean;
12917 -- If Subp is a private overriding of a visible operation, the inherited
12918 -- operation derives from the overridden op (even though its body is the
12919 -- overriding one) and the inherited operation is visible now. See
12920 -- sem_disp to see the full details of the handling of the overridden
12921 -- subprogram, which is removed from the list of primitive operations of
12922 -- the type. The overridden subprogram is saved locally in Visible_Subp,
12923 -- and used to diagnose abstract operations that need overriding in the
12926 procedure Replace_Type (Id, New_Id : Entity_Id);
12927 -- When the type is an anonymous access type, create a new access type
12928 -- designating the derived type.
12930 procedure Set_Derived_Name;
12931 -- This procedure sets the appropriate Chars name for New_Subp. This
12932 -- is normally just a copy of the parent name. An exception arises for
12933 -- type support subprograms, where the name is changed to reflect the
12934 -- name of the derived type, e.g. if type foo is derived from type bar,
12935 -- then a procedure barDA is derived with a name fooDA.
12937 ---------------------------
12938 -- Is_Private_Overriding --
12939 ---------------------------
12941 function Is_Private_Overriding return Boolean is
12945 -- If the parent is not a dispatching operation there is no
12946 -- need to investigate overridings
12948 if not Is_Dispatching_Operation (Parent_Subp) then
12952 -- The visible operation that is overridden is a homonym of the
12953 -- parent subprogram. We scan the homonym chain to find the one
12954 -- whose alias is the subprogram we are deriving.
12956 Prev := Current_Entity (Parent_Subp);
12957 while Present (Prev) loop
12958 if Ekind (Prev) = Ekind (Parent_Subp)
12959 and then Alias (Prev) = Parent_Subp
12960 and then Scope (Parent_Subp) = Scope (Prev)
12961 and then not Is_Hidden (Prev)
12963 Visible_Subp := Prev;
12967 Prev := Homonym (Prev);
12971 end Is_Private_Overriding;
12977 procedure Replace_Type (Id, New_Id : Entity_Id) is
12978 Acc_Type : Entity_Id;
12979 Par : constant Node_Id := Parent (Derived_Type);
12982 -- When the type is an anonymous access type, create a new access
12983 -- type designating the derived type. This itype must be elaborated
12984 -- at the point of the derivation, not on subsequent calls that may
12985 -- be out of the proper scope for Gigi, so we insert a reference to
12986 -- it after the derivation.
12988 if Ekind (Etype (Id)) = E_Anonymous_Access_Type then
12990 Desig_Typ : Entity_Id := Designated_Type (Etype (Id));
12993 if Ekind (Desig_Typ) = E_Record_Type_With_Private
12994 and then Present (Full_View (Desig_Typ))
12995 and then not Is_Private_Type (Parent_Type)
12997 Desig_Typ := Full_View (Desig_Typ);
13000 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
13002 -- Ada 2005 (AI-251): Handle also derivations of abstract
13003 -- interface primitives.
13005 or else (Is_Interface (Desig_Typ)
13006 and then not Is_Class_Wide_Type (Desig_Typ))
13008 Acc_Type := New_Copy (Etype (Id));
13009 Set_Etype (Acc_Type, Acc_Type);
13010 Set_Scope (Acc_Type, New_Subp);
13012 -- Compute size of anonymous access type
13014 if Is_Array_Type (Desig_Typ)
13015 and then not Is_Constrained (Desig_Typ)
13017 Init_Size (Acc_Type, 2 * System_Address_Size);
13019 Init_Size (Acc_Type, System_Address_Size);
13022 Init_Alignment (Acc_Type);
13023 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
13025 Set_Etype (New_Id, Acc_Type);
13026 Set_Scope (New_Id, New_Subp);
13028 -- Create a reference to it
13029 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
13032 Set_Etype (New_Id, Etype (Id));
13036 elsif Base_Type (Etype (Id)) = Base_Type (Parent_Type)
13038 (Ekind (Etype (Id)) = E_Record_Type_With_Private
13039 and then Present (Full_View (Etype (Id)))
13041 Base_Type (Full_View (Etype (Id))) = Base_Type (Parent_Type))
13043 -- Constraint checks on formals are generated during expansion,
13044 -- based on the signature of the original subprogram. The bounds
13045 -- of the derived type are not relevant, and thus we can use
13046 -- the base type for the formals. However, the return type may be
13047 -- used in a context that requires that the proper static bounds
13048 -- be used (a case statement, for example) and for those cases
13049 -- we must use the derived type (first subtype), not its base.
13051 -- If the derived_type_definition has no constraints, we know that
13052 -- the derived type has the same constraints as the first subtype
13053 -- of the parent, and we can also use it rather than its base,
13054 -- which can lead to more efficient code.
13056 if Etype (Id) = Parent_Type then
13057 if Is_Scalar_Type (Parent_Type)
13059 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
13061 Set_Etype (New_Id, Derived_Type);
13063 elsif Nkind (Par) = N_Full_Type_Declaration
13065 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
13068 (Subtype_Indication (Type_Definition (Par)))
13070 Set_Etype (New_Id, Derived_Type);
13073 Set_Etype (New_Id, Base_Type (Derived_Type));
13077 Set_Etype (New_Id, Base_Type (Derived_Type));
13081 Set_Etype (New_Id, Etype (Id));
13085 ----------------------
13086 -- Set_Derived_Name --
13087 ----------------------
13089 procedure Set_Derived_Name is
13090 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
13092 if Nm = TSS_Null then
13093 Set_Chars (New_Subp, Chars (Parent_Subp));
13095 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
13097 end Set_Derived_Name;
13099 -- Start of processing for Derive_Subprogram
13103 New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
13104 Set_Ekind (New_Subp, Ekind (Parent_Subp));
13105 Set_Contract (New_Subp, Make_Contract (Sloc (New_Subp)));
13107 -- Check whether the inherited subprogram is a private operation that
13108 -- should be inherited but not yet made visible. Such subprograms can
13109 -- become visible at a later point (e.g., the private part of a public
13110 -- child unit) via Declare_Inherited_Private_Subprograms. If the
13111 -- following predicate is true, then this is not such a private
13112 -- operation and the subprogram simply inherits the name of the parent
13113 -- subprogram. Note the special check for the names of controlled
13114 -- operations, which are currently exempted from being inherited with
13115 -- a hidden name because they must be findable for generation of
13116 -- implicit run-time calls.
13118 if not Is_Hidden (Parent_Subp)
13119 or else Is_Internal (Parent_Subp)
13120 or else Is_Private_Overriding
13121 or else Is_Internal_Name (Chars (Parent_Subp))
13122 or else Chars (Parent_Subp) = Name_Initialize
13123 or else Chars (Parent_Subp) = Name_Adjust
13124 or else Chars (Parent_Subp) = Name_Finalize
13128 -- An inherited dispatching equality will be overridden by an internally
13129 -- generated one, or by an explicit one, so preserve its name and thus
13130 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
13131 -- private operation it may become invisible if the full view has
13132 -- progenitors, and the dispatch table will be malformed.
13133 -- We check that the type is limited to handle the anomalous declaration
13134 -- of Limited_Controlled, which is derived from a non-limited type, and
13135 -- which is handled specially elsewhere as well.
13137 elsif Chars (Parent_Subp) = Name_Op_Eq
13138 and then Is_Dispatching_Operation (Parent_Subp)
13139 and then Etype (Parent_Subp) = Standard_Boolean
13140 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
13142 Etype (First_Formal (Parent_Subp)) =
13143 Etype (Next_Formal (First_Formal (Parent_Subp)))
13147 -- If parent is hidden, this can be a regular derivation if the
13148 -- parent is immediately visible in a non-instantiating context,
13149 -- or if we are in the private part of an instance. This test
13150 -- should still be refined ???
13152 -- The test for In_Instance_Not_Visible avoids inheriting the derived
13153 -- operation as a non-visible operation in cases where the parent
13154 -- subprogram might not be visible now, but was visible within the
13155 -- original generic, so it would be wrong to make the inherited
13156 -- subprogram non-visible now. (Not clear if this test is fully
13157 -- correct; are there any cases where we should declare the inherited
13158 -- operation as not visible to avoid it being overridden, e.g., when
13159 -- the parent type is a generic actual with private primitives ???)
13161 -- (they should be treated the same as other private inherited
13162 -- subprograms, but it's not clear how to do this cleanly). ???
13164 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
13165 and then Is_Immediately_Visible (Parent_Subp)
13166 and then not In_Instance)
13167 or else In_Instance_Not_Visible
13171 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
13172 -- overrides an interface primitive because interface primitives
13173 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
13175 elsif Ada_Version >= Ada_2005
13176 and then Is_Dispatching_Operation (Parent_Subp)
13177 and then Covers_Some_Interface (Parent_Subp)
13181 -- Otherwise, the type is inheriting a private operation, so enter
13182 -- it with a special name so it can't be overridden.
13185 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
13188 Set_Parent (New_Subp, Parent (Derived_Type));
13190 if Present (Actual_Subp) then
13191 Replace_Type (Actual_Subp, New_Subp);
13193 Replace_Type (Parent_Subp, New_Subp);
13196 Conditional_Delay (New_Subp, Parent_Subp);
13198 -- If we are creating a renaming for a primitive operation of an
13199 -- actual of a generic derived type, we must examine the signature
13200 -- of the actual primitive, not that of the generic formal, which for
13201 -- example may be an interface. However the name and initial value
13202 -- of the inherited operation are those of the formal primitive.
13204 Formal := First_Formal (Parent_Subp);
13206 if Present (Actual_Subp) then
13207 Formal_Of_Actual := First_Formal (Actual_Subp);
13209 Formal_Of_Actual := Empty;
13212 while Present (Formal) loop
13213 New_Formal := New_Copy (Formal);
13215 -- Normally we do not go copying parents, but in the case of
13216 -- formals, we need to link up to the declaration (which is the
13217 -- parameter specification), and it is fine to link up to the
13218 -- original formal's parameter specification in this case.
13220 Set_Parent (New_Formal, Parent (Formal));
13221 Append_Entity (New_Formal, New_Subp);
13223 if Present (Formal_Of_Actual) then
13224 Replace_Type (Formal_Of_Actual, New_Formal);
13225 Next_Formal (Formal_Of_Actual);
13227 Replace_Type (Formal, New_Formal);
13230 Next_Formal (Formal);
13233 -- If this derivation corresponds to a tagged generic actual, then
13234 -- primitive operations rename those of the actual. Otherwise the
13235 -- primitive operations rename those of the parent type, If the parent
13236 -- renames an intrinsic operator, so does the new subprogram. We except
13237 -- concatenation, which is always properly typed, and does not get
13238 -- expanded as other intrinsic operations.
13240 if No (Actual_Subp) then
13241 if Is_Intrinsic_Subprogram (Parent_Subp) then
13242 Set_Is_Intrinsic_Subprogram (New_Subp);
13244 if Present (Alias (Parent_Subp))
13245 and then Chars (Parent_Subp) /= Name_Op_Concat
13247 Set_Alias (New_Subp, Alias (Parent_Subp));
13249 Set_Alias (New_Subp, Parent_Subp);
13253 Set_Alias (New_Subp, Parent_Subp);
13257 Set_Alias (New_Subp, Actual_Subp);
13260 -- Derived subprograms of a tagged type must inherit the convention
13261 -- of the parent subprogram (a requirement of AI-117). Derived
13262 -- subprograms of untagged types simply get convention Ada by default.
13264 if Is_Tagged_Type (Derived_Type) then
13265 Set_Convention (New_Subp, Convention (Parent_Subp));
13268 -- Predefined controlled operations retain their name even if the parent
13269 -- is hidden (see above), but they are not primitive operations if the
13270 -- ancestor is not visible, for example if the parent is a private
13271 -- extension completed with a controlled extension. Note that a full
13272 -- type that is controlled can break privacy: the flag Is_Controlled is
13273 -- set on both views of the type.
13275 if Is_Controlled (Parent_Type)
13277 (Chars (Parent_Subp) = Name_Initialize
13278 or else Chars (Parent_Subp) = Name_Adjust
13279 or else Chars (Parent_Subp) = Name_Finalize)
13280 and then Is_Hidden (Parent_Subp)
13281 and then not Is_Visibly_Controlled (Parent_Type)
13283 Set_Is_Hidden (New_Subp);
13286 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
13287 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
13289 if Ekind (Parent_Subp) = E_Procedure then
13290 Set_Is_Valued_Procedure
13291 (New_Subp, Is_Valued_Procedure (Parent_Subp));
13293 Set_Has_Controlling_Result
13294 (New_Subp, Has_Controlling_Result (Parent_Subp));
13297 -- No_Return must be inherited properly. If this is overridden in the
13298 -- case of a dispatching operation, then a check is made in Sem_Disp
13299 -- that the overriding operation is also No_Return (no such check is
13300 -- required for the case of non-dispatching operation.
13302 Set_No_Return (New_Subp, No_Return (Parent_Subp));
13304 -- A derived function with a controlling result is abstract. If the
13305 -- Derived_Type is a nonabstract formal generic derived type, then
13306 -- inherited operations are not abstract: the required check is done at
13307 -- instantiation time. If the derivation is for a generic actual, the
13308 -- function is not abstract unless the actual is.
13310 if Is_Generic_Type (Derived_Type)
13311 and then not Is_Abstract_Type (Derived_Type)
13315 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
13316 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
13318 elsif Ada_Version >= Ada_2005
13319 and then (Is_Abstract_Subprogram (Alias (New_Subp))
13320 or else (Is_Tagged_Type (Derived_Type)
13321 and then Etype (New_Subp) = Derived_Type
13322 and then not Is_Null_Extension (Derived_Type))
13323 or else (Is_Tagged_Type (Derived_Type)
13324 and then Ekind (Etype (New_Subp)) =
13325 E_Anonymous_Access_Type
13326 and then Designated_Type (Etype (New_Subp)) =
13328 and then not Is_Null_Extension (Derived_Type)))
13329 and then No (Actual_Subp)
13331 if not Is_Tagged_Type (Derived_Type)
13332 or else Is_Abstract_Type (Derived_Type)
13333 or else Is_Abstract_Subprogram (Alias (New_Subp))
13335 Set_Is_Abstract_Subprogram (New_Subp);
13337 Set_Requires_Overriding (New_Subp);
13340 elsif Ada_Version < Ada_2005
13341 and then (Is_Abstract_Subprogram (Alias (New_Subp))
13342 or else (Is_Tagged_Type (Derived_Type)
13343 and then Etype (New_Subp) = Derived_Type
13344 and then No (Actual_Subp)))
13346 Set_Is_Abstract_Subprogram (New_Subp);
13348 -- AI05-0097 : an inherited operation that dispatches on result is
13349 -- abstract if the derived type is abstract, even if the parent type
13350 -- is concrete and the derived type is a null extension.
13352 elsif Has_Controlling_Result (Alias (New_Subp))
13353 and then Is_Abstract_Type (Etype (New_Subp))
13355 Set_Is_Abstract_Subprogram (New_Subp);
13357 -- Finally, if the parent type is abstract we must verify that all
13358 -- inherited operations are either non-abstract or overridden, or that
13359 -- the derived type itself is abstract (this check is performed at the
13360 -- end of a package declaration, in Check_Abstract_Overriding). A
13361 -- private overriding in the parent type will not be visible in the
13362 -- derivation if we are not in an inner package or in a child unit of
13363 -- the parent type, in which case the abstractness of the inherited
13364 -- operation is carried to the new subprogram.
13366 elsif Is_Abstract_Type (Parent_Type)
13367 and then not In_Open_Scopes (Scope (Parent_Type))
13368 and then Is_Private_Overriding
13369 and then Is_Abstract_Subprogram (Visible_Subp)
13371 if No (Actual_Subp) then
13372 Set_Alias (New_Subp, Visible_Subp);
13373 Set_Is_Abstract_Subprogram (New_Subp, True);
13376 -- If this is a derivation for an instance of a formal derived
13377 -- type, abstractness comes from the primitive operation of the
13378 -- actual, not from the operation inherited from the ancestor.
13380 Set_Is_Abstract_Subprogram
13381 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
13385 New_Overloaded_Entity (New_Subp, Derived_Type);
13387 -- Check for case of a derived subprogram for the instantiation of a
13388 -- formal derived tagged type, if so mark the subprogram as dispatching
13389 -- and inherit the dispatching attributes of the actual subprogram. The
13390 -- derived subprogram is effectively renaming of the actual subprogram,
13391 -- so it needs to have the same attributes as the actual.
13393 if Present (Actual_Subp)
13394 and then Is_Dispatching_Operation (Actual_Subp)
13396 Set_Is_Dispatching_Operation (New_Subp);
13398 if Present (DTC_Entity (Actual_Subp)) then
13399 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
13400 Set_DT_Position (New_Subp, DT_Position (Actual_Subp));
13404 -- Indicate that a derived subprogram does not require a body and that
13405 -- it does not require processing of default expressions.
13407 Set_Has_Completion (New_Subp);
13408 Set_Default_Expressions_Processed (New_Subp);
13410 if Ekind (New_Subp) = E_Function then
13411 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
13413 end Derive_Subprogram;
13415 ------------------------
13416 -- Derive_Subprograms --
13417 ------------------------
13419 procedure Derive_Subprograms
13420 (Parent_Type : Entity_Id;
13421 Derived_Type : Entity_Id;
13422 Generic_Actual : Entity_Id := Empty)
13424 Op_List : constant Elist_Id :=
13425 Collect_Primitive_Operations (Parent_Type);
13427 function Check_Derived_Type return Boolean;
13428 -- Check that all the entities derived from Parent_Type are found in
13429 -- the list of primitives of Derived_Type exactly in the same order.
13431 procedure Derive_Interface_Subprogram
13432 (New_Subp : in out Entity_Id;
13434 Actual_Subp : Entity_Id);
13435 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
13436 -- (which is an interface primitive). If Generic_Actual is present then
13437 -- Actual_Subp is the actual subprogram corresponding with the generic
13438 -- subprogram Subp.
13440 function Check_Derived_Type return Boolean is
13444 New_Subp : Entity_Id;
13449 -- Traverse list of entities in the current scope searching for
13450 -- an incomplete type whose full-view is derived type
13452 E := First_Entity (Scope (Derived_Type));
13454 and then E /= Derived_Type
13456 if Ekind (E) = E_Incomplete_Type
13457 and then Present (Full_View (E))
13458 and then Full_View (E) = Derived_Type
13460 -- Disable this test if Derived_Type completes an incomplete
13461 -- type because in such case more primitives can be added
13462 -- later to the list of primitives of Derived_Type by routine
13463 -- Process_Incomplete_Dependents
13468 E := Next_Entity (E);
13471 List := Collect_Primitive_Operations (Derived_Type);
13472 Elmt := First_Elmt (List);
13474 Op_Elmt := First_Elmt (Op_List);
13475 while Present (Op_Elmt) loop
13476 Subp := Node (Op_Elmt);
13477 New_Subp := Node (Elmt);
13479 -- At this early stage Derived_Type has no entities with attribute
13480 -- Interface_Alias. In addition, such primitives are always
13481 -- located at the end of the list of primitives of Parent_Type.
13482 -- Therefore, if found we can safely stop processing pending
13485 exit when Present (Interface_Alias (Subp));
13487 -- Handle hidden entities
13489 if not Is_Predefined_Dispatching_Operation (Subp)
13490 and then Is_Hidden (Subp)
13492 if Present (New_Subp)
13493 and then Primitive_Names_Match (Subp, New_Subp)
13499 if not Present (New_Subp)
13500 or else Ekind (Subp) /= Ekind (New_Subp)
13501 or else not Primitive_Names_Match (Subp, New_Subp)
13509 Next_Elmt (Op_Elmt);
13513 end Check_Derived_Type;
13515 ---------------------------------
13516 -- Derive_Interface_Subprogram --
13517 ---------------------------------
13519 procedure Derive_Interface_Subprogram
13520 (New_Subp : in out Entity_Id;
13522 Actual_Subp : Entity_Id)
13524 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
13525 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
13528 pragma Assert (Is_Interface (Iface_Type));
13531 (New_Subp => New_Subp,
13532 Parent_Subp => Iface_Subp,
13533 Derived_Type => Derived_Type,
13534 Parent_Type => Iface_Type,
13535 Actual_Subp => Actual_Subp);
13537 -- Given that this new interface entity corresponds with a primitive
13538 -- of the parent that was not overridden we must leave it associated
13539 -- with its parent primitive to ensure that it will share the same
13540 -- dispatch table slot when overridden.
13542 if No (Actual_Subp) then
13543 Set_Alias (New_Subp, Subp);
13545 -- For instantiations this is not needed since the previous call to
13546 -- Derive_Subprogram leaves the entity well decorated.
13549 pragma Assert (Alias (New_Subp) = Actual_Subp);
13552 end Derive_Interface_Subprogram;
13556 Alias_Subp : Entity_Id;
13557 Act_List : Elist_Id;
13558 Act_Elmt : Elmt_Id := No_Elmt;
13559 Act_Subp : Entity_Id := Empty;
13561 Need_Search : Boolean := False;
13562 New_Subp : Entity_Id := Empty;
13563 Parent_Base : Entity_Id;
13566 -- Start of processing for Derive_Subprograms
13569 if Ekind (Parent_Type) = E_Record_Type_With_Private
13570 and then Has_Discriminants (Parent_Type)
13571 and then Present (Full_View (Parent_Type))
13573 Parent_Base := Full_View (Parent_Type);
13575 Parent_Base := Parent_Type;
13578 if Present (Generic_Actual) then
13579 Act_List := Collect_Primitive_Operations (Generic_Actual);
13580 Act_Elmt := First_Elmt (Act_List);
13583 -- Derive primitives inherited from the parent. Note that if the generic
13584 -- actual is present, this is not really a type derivation, it is a
13585 -- completion within an instance.
13587 -- Case 1: Derived_Type does not implement interfaces
13589 if not Is_Tagged_Type (Derived_Type)
13590 or else (not Has_Interfaces (Derived_Type)
13591 and then not (Present (Generic_Actual)
13593 Has_Interfaces (Generic_Actual)))
13595 Elmt := First_Elmt (Op_List);
13596 while Present (Elmt) loop
13597 Subp := Node (Elmt);
13599 -- Literals are derived earlier in the process of building the
13600 -- derived type, and are skipped here.
13602 if Ekind (Subp) = E_Enumeration_Literal then
13605 -- The actual is a direct descendant and the common primitive
13606 -- operations appear in the same order.
13608 -- If the generic parent type is present, the derived type is an
13609 -- instance of a formal derived type, and within the instance its
13610 -- operations are those of the actual. We derive from the formal
13611 -- type but make the inherited operations aliases of the
13612 -- corresponding operations of the actual.
13615 pragma Assert (No (Node (Act_Elmt))
13616 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
13618 Type_Conformant (Subp, Node (Act_Elmt),
13619 Skip_Controlling_Formals => True)));
13622 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
13624 if Present (Act_Elmt) then
13625 Next_Elmt (Act_Elmt);
13632 -- Case 2: Derived_Type implements interfaces
13635 -- If the parent type has no predefined primitives we remove
13636 -- predefined primitives from the list of primitives of generic
13637 -- actual to simplify the complexity of this algorithm.
13639 if Present (Generic_Actual) then
13641 Has_Predefined_Primitives : Boolean := False;
13644 -- Check if the parent type has predefined primitives
13646 Elmt := First_Elmt (Op_List);
13647 while Present (Elmt) loop
13648 Subp := Node (Elmt);
13650 if Is_Predefined_Dispatching_Operation (Subp)
13651 and then not Comes_From_Source (Ultimate_Alias (Subp))
13653 Has_Predefined_Primitives := True;
13660 -- Remove predefined primitives of Generic_Actual. We must use
13661 -- an auxiliary list because in case of tagged types the value
13662 -- returned by Collect_Primitive_Operations is the value stored
13663 -- in its Primitive_Operations attribute (and we don't want to
13664 -- modify its current contents).
13666 if not Has_Predefined_Primitives then
13668 Aux_List : constant Elist_Id := New_Elmt_List;
13671 Elmt := First_Elmt (Act_List);
13672 while Present (Elmt) loop
13673 Subp := Node (Elmt);
13675 if not Is_Predefined_Dispatching_Operation (Subp)
13676 or else Comes_From_Source (Subp)
13678 Append_Elmt (Subp, Aux_List);
13684 Act_List := Aux_List;
13688 Act_Elmt := First_Elmt (Act_List);
13689 Act_Subp := Node (Act_Elmt);
13693 -- Stage 1: If the generic actual is not present we derive the
13694 -- primitives inherited from the parent type. If the generic parent
13695 -- type is present, the derived type is an instance of a formal
13696 -- derived type, and within the instance its operations are those of
13697 -- the actual. We derive from the formal type but make the inherited
13698 -- operations aliases of the corresponding operations of the actual.
13700 Elmt := First_Elmt (Op_List);
13701 while Present (Elmt) loop
13702 Subp := Node (Elmt);
13703 Alias_Subp := Ultimate_Alias (Subp);
13705 -- Do not derive internal entities of the parent that link
13706 -- interface primitives with their covering primitive. These
13707 -- entities will be added to this type when frozen.
13709 if Present (Interface_Alias (Subp)) then
13713 -- If the generic actual is present find the corresponding
13714 -- operation in the generic actual. If the parent type is a
13715 -- direct ancestor of the derived type then, even if it is an
13716 -- interface, the operations are inherited from the primary
13717 -- dispatch table and are in the proper order. If we detect here
13718 -- that primitives are not in the same order we traverse the list
13719 -- of primitive operations of the actual to find the one that
13720 -- implements the interface primitive.
13724 (Present (Generic_Actual)
13725 and then Present (Act_Subp)
13727 (Primitive_Names_Match (Subp, Act_Subp)
13729 Type_Conformant (Subp, Act_Subp,
13730 Skip_Controlling_Formals => True)))
13732 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
13733 Use_Full_View => True));
13735 -- Remember that we need searching for all pending primitives
13737 Need_Search := True;
13739 -- Handle entities associated with interface primitives
13741 if Present (Alias_Subp)
13742 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
13743 and then not Is_Predefined_Dispatching_Operation (Subp)
13745 -- Search for the primitive in the homonym chain
13748 Find_Primitive_Covering_Interface
13749 (Tagged_Type => Generic_Actual,
13750 Iface_Prim => Alias_Subp);
13752 -- Previous search may not locate primitives covering
13753 -- interfaces defined in generics units or instantiations.
13754 -- (it fails if the covering primitive has formals whose
13755 -- type is also defined in generics or instantiations).
13756 -- In such case we search in the list of primitives of the
13757 -- generic actual for the internal entity that links the
13758 -- interface primitive and the covering primitive.
13761 and then Is_Generic_Type (Parent_Type)
13763 -- This code has been designed to handle only generic
13764 -- formals that implement interfaces that are defined
13765 -- in a generic unit or instantiation. If this code is
13766 -- needed for other cases we must review it because
13767 -- (given that it relies on Original_Location to locate
13768 -- the primitive of Generic_Actual that covers the
13769 -- interface) it could leave linked through attribute
13770 -- Alias entities of unrelated instantiations).
13774 (Scope (Find_Dispatching_Type (Alias_Subp)))
13776 Instantiation_Depth
13777 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
13780 Iface_Prim_Loc : constant Source_Ptr :=
13781 Original_Location (Sloc (Alias_Subp));
13786 First_Elmt (Primitive_Operations (Generic_Actual));
13788 Search : while Present (Elmt) loop
13789 Prim := Node (Elmt);
13791 if Present (Interface_Alias (Prim))
13792 and then Original_Location
13793 (Sloc (Interface_Alias (Prim)))
13796 Act_Subp := Alias (Prim);
13805 pragma Assert (Present (Act_Subp)
13806 or else Is_Abstract_Type (Generic_Actual)
13807 or else Serious_Errors_Detected > 0);
13809 -- Handle predefined primitives plus the rest of user-defined
13813 Act_Elmt := First_Elmt (Act_List);
13814 while Present (Act_Elmt) loop
13815 Act_Subp := Node (Act_Elmt);
13817 exit when Primitive_Names_Match (Subp, Act_Subp)
13818 and then Type_Conformant
13820 Skip_Controlling_Formals => True)
13821 and then No (Interface_Alias (Act_Subp));
13823 Next_Elmt (Act_Elmt);
13826 if No (Act_Elmt) then
13832 -- Case 1: If the parent is a limited interface then it has the
13833 -- predefined primitives of synchronized interfaces. However, the
13834 -- actual type may be a non-limited type and hence it does not
13835 -- have such primitives.
13837 if Present (Generic_Actual)
13838 and then not Present (Act_Subp)
13839 and then Is_Limited_Interface (Parent_Base)
13840 and then Is_Predefined_Interface_Primitive (Subp)
13844 -- Case 2: Inherit entities associated with interfaces that were
13845 -- not covered by the parent type. We exclude here null interface
13846 -- primitives because they do not need special management.
13848 -- We also exclude interface operations that are renamings. If the
13849 -- subprogram is an explicit renaming of an interface primitive,
13850 -- it is a regular primitive operation, and the presence of its
13851 -- alias is not relevant: it has to be derived like any other
13854 elsif Present (Alias (Subp))
13855 and then Nkind (Unit_Declaration_Node (Subp)) /=
13856 N_Subprogram_Renaming_Declaration
13857 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
13859 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
13860 and then Null_Present (Parent (Alias_Subp)))
13862 -- If this is an abstract private type then we transfer the
13863 -- derivation of the interface primitive from the partial view
13864 -- to the full view. This is safe because all the interfaces
13865 -- must be visible in the partial view. Done to avoid adding
13866 -- a new interface derivation to the private part of the
13867 -- enclosing package; otherwise this new derivation would be
13868 -- decorated as hidden when the analysis of the enclosing
13869 -- package completes.
13871 if Is_Abstract_Type (Derived_Type)
13872 and then In_Private_Part (Current_Scope)
13873 and then Has_Private_Declaration (Derived_Type)
13876 Partial_View : Entity_Id;
13881 Partial_View := First_Entity (Current_Scope);
13883 exit when No (Partial_View)
13884 or else (Has_Private_Declaration (Partial_View)
13886 Full_View (Partial_View) = Derived_Type);
13888 Next_Entity (Partial_View);
13891 -- If the partial view was not found then the source code
13892 -- has errors and the derivation is not needed.
13894 if Present (Partial_View) then
13896 First_Elmt (Primitive_Operations (Partial_View));
13897 while Present (Elmt) loop
13898 Ent := Node (Elmt);
13900 if Present (Alias (Ent))
13901 and then Ultimate_Alias (Ent) = Alias (Subp)
13904 (Ent, Primitive_Operations (Derived_Type));
13911 -- If the interface primitive was not found in the
13912 -- partial view then this interface primitive was
13913 -- overridden. We add a derivation to activate in
13914 -- Derive_Progenitor_Subprograms the machinery to
13918 Derive_Interface_Subprogram
13919 (New_Subp => New_Subp,
13921 Actual_Subp => Act_Subp);
13926 Derive_Interface_Subprogram
13927 (New_Subp => New_Subp,
13929 Actual_Subp => Act_Subp);
13932 -- Case 3: Common derivation
13936 (New_Subp => New_Subp,
13937 Parent_Subp => Subp,
13938 Derived_Type => Derived_Type,
13939 Parent_Type => Parent_Base,
13940 Actual_Subp => Act_Subp);
13943 -- No need to update Act_Elm if we must search for the
13944 -- corresponding operation in the generic actual
13947 and then Present (Act_Elmt)
13949 Next_Elmt (Act_Elmt);
13950 Act_Subp := Node (Act_Elmt);
13957 -- Inherit additional operations from progenitors. If the derived
13958 -- type is a generic actual, there are not new primitive operations
13959 -- for the type because it has those of the actual, and therefore
13960 -- nothing needs to be done. The renamings generated above are not
13961 -- primitive operations, and their purpose is simply to make the
13962 -- proper operations visible within an instantiation.
13964 if No (Generic_Actual) then
13965 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
13969 -- Final check: Direct descendants must have their primitives in the
13970 -- same order. We exclude from this test untagged types and instances
13971 -- of formal derived types. We skip this test if we have already
13972 -- reported serious errors in the sources.
13974 pragma Assert (not Is_Tagged_Type (Derived_Type)
13975 or else Present (Generic_Actual)
13976 or else Serious_Errors_Detected > 0
13977 or else Check_Derived_Type);
13978 end Derive_Subprograms;
13980 --------------------------------
13981 -- Derived_Standard_Character --
13982 --------------------------------
13984 procedure Derived_Standard_Character
13986 Parent_Type : Entity_Id;
13987 Derived_Type : Entity_Id)
13989 Loc : constant Source_Ptr := Sloc (N);
13990 Def : constant Node_Id := Type_Definition (N);
13991 Indic : constant Node_Id := Subtype_Indication (Def);
13992 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
13993 Implicit_Base : constant Entity_Id :=
13995 (E_Enumeration_Type, N, Derived_Type, 'B');
14001 Discard_Node (Process_Subtype (Indic, N));
14003 Set_Etype (Implicit_Base, Parent_Base);
14004 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
14005 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
14007 Set_Is_Character_Type (Implicit_Base, True);
14008 Set_Has_Delayed_Freeze (Implicit_Base);
14010 -- The bounds of the implicit base are the bounds of the parent base.
14011 -- Note that their type is the parent base.
14013 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
14014 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
14016 Set_Scalar_Range (Implicit_Base,
14019 High_Bound => Hi));
14021 Conditional_Delay (Derived_Type, Parent_Type);
14023 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
14024 Set_Etype (Derived_Type, Implicit_Base);
14025 Set_Size_Info (Derived_Type, Parent_Type);
14027 if Unknown_RM_Size (Derived_Type) then
14028 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
14031 Set_Is_Character_Type (Derived_Type, True);
14033 if Nkind (Indic) /= N_Subtype_Indication then
14035 -- If no explicit constraint, the bounds are those
14036 -- of the parent type.
14038 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
14039 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
14040 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
14043 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
14045 -- Because the implicit base is used in the conversion of the bounds, we
14046 -- have to freeze it now. This is similar to what is done for numeric
14047 -- types, and it equally suspicious, but otherwise a non-static bound
14048 -- will have a reference to an unfrozen type, which is rejected by Gigi
14049 -- (???). This requires specific care for definition of stream
14050 -- attributes. For details, see comments at the end of
14051 -- Build_Derived_Numeric_Type.
14053 Freeze_Before (N, Implicit_Base);
14054 end Derived_Standard_Character;
14056 ------------------------------
14057 -- Derived_Type_Declaration --
14058 ------------------------------
14060 procedure Derived_Type_Declaration
14063 Is_Completion : Boolean)
14065 Parent_Type : Entity_Id;
14067 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
14068 -- Check whether the parent type is a generic formal, or derives
14069 -- directly or indirectly from one.
14071 ------------------------
14072 -- Comes_From_Generic --
14073 ------------------------
14075 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
14077 if Is_Generic_Type (Typ) then
14080 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
14083 elsif Is_Private_Type (Typ)
14084 and then Present (Full_View (Typ))
14085 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
14089 elsif Is_Generic_Actual_Type (Typ) then
14095 end Comes_From_Generic;
14099 Def : constant Node_Id := Type_Definition (N);
14100 Iface_Def : Node_Id;
14101 Indic : constant Node_Id := Subtype_Indication (Def);
14102 Extension : constant Node_Id := Record_Extension_Part (Def);
14103 Parent_Node : Node_Id;
14106 -- Start of processing for Derived_Type_Declaration
14109 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
14111 -- Ada 2005 (AI-251): In case of interface derivation check that the
14112 -- parent is also an interface.
14114 if Interface_Present (Def) then
14115 Check_SPARK_Restriction ("interface is not allowed", Def);
14117 if not Is_Interface (Parent_Type) then
14118 Diagnose_Interface (Indic, Parent_Type);
14121 Parent_Node := Parent (Base_Type (Parent_Type));
14122 Iface_Def := Type_Definition (Parent_Node);
14124 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
14125 -- other limited interfaces.
14127 if Limited_Present (Def) then
14128 if Limited_Present (Iface_Def) then
14131 elsif Protected_Present (Iface_Def) then
14133 ("descendant of& must be declared"
14134 & " as a protected interface",
14137 elsif Synchronized_Present (Iface_Def) then
14139 ("descendant of& must be declared"
14140 & " as a synchronized interface",
14143 elsif Task_Present (Iface_Def) then
14145 ("descendant of& must be declared as a task interface",
14150 ("(Ada 2005) limited interface cannot "
14151 & "inherit from non-limited interface", Indic);
14154 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
14155 -- from non-limited or limited interfaces.
14157 elsif not Protected_Present (Def)
14158 and then not Synchronized_Present (Def)
14159 and then not Task_Present (Def)
14161 if Limited_Present (Iface_Def) then
14164 elsif Protected_Present (Iface_Def) then
14166 ("descendant of& must be declared"
14167 & " as a protected interface",
14170 elsif Synchronized_Present (Iface_Def) then
14172 ("descendant of& must be declared"
14173 & " as a synchronized interface",
14176 elsif Task_Present (Iface_Def) then
14178 ("descendant of& must be declared as a task interface",
14187 if Is_Tagged_Type (Parent_Type)
14188 and then Is_Concurrent_Type (Parent_Type)
14189 and then not Is_Interface (Parent_Type)
14192 ("parent type of a record extension cannot be "
14193 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
14194 Set_Etype (T, Any_Type);
14198 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
14201 if Is_Tagged_Type (Parent_Type)
14202 and then Is_Non_Empty_List (Interface_List (Def))
14209 Intf := First (Interface_List (Def));
14210 while Present (Intf) loop
14211 T := Find_Type_Of_Subtype_Indic (Intf);
14213 if not Is_Interface (T) then
14214 Diagnose_Interface (Intf, T);
14216 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
14217 -- a limited type from having a nonlimited progenitor.
14219 elsif (Limited_Present (Def)
14220 or else (not Is_Interface (Parent_Type)
14221 and then Is_Limited_Type (Parent_Type)))
14222 and then not Is_Limited_Interface (T)
14225 ("progenitor interface& of limited type must be limited",
14234 if Parent_Type = Any_Type
14235 or else Etype (Parent_Type) = Any_Type
14236 or else (Is_Class_Wide_Type (Parent_Type)
14237 and then Etype (Parent_Type) = T)
14239 -- If Parent_Type is undefined or illegal, make new type into a
14240 -- subtype of Any_Type, and set a few attributes to prevent cascaded
14241 -- errors. If this is a self-definition, emit error now.
14244 or else T = Etype (Parent_Type)
14246 Error_Msg_N ("type cannot be used in its own definition", Indic);
14249 Set_Ekind (T, Ekind (Parent_Type));
14250 Set_Etype (T, Any_Type);
14251 Set_Scalar_Range (T, Scalar_Range (Any_Type));
14253 if Is_Tagged_Type (T)
14254 and then Is_Record_Type (T)
14256 Set_Direct_Primitive_Operations (T, New_Elmt_List);
14262 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
14263 -- an interface is special because the list of interfaces in the full
14264 -- view can be given in any order. For example:
14266 -- type A is interface;
14267 -- type B is interface and A;
14268 -- type D is new B with private;
14270 -- type D is new A and B with null record; -- 1 --
14272 -- In this case we perform the following transformation of -1-:
14274 -- type D is new B and A with null record;
14276 -- If the parent of the full-view covers the parent of the partial-view
14277 -- we have two possible cases:
14279 -- 1) They have the same parent
14280 -- 2) The parent of the full-view implements some further interfaces
14282 -- In both cases we do not need to perform the transformation. In the
14283 -- first case the source program is correct and the transformation is
14284 -- not needed; in the second case the source program does not fulfill
14285 -- the no-hidden interfaces rule (AI-396) and the error will be reported
14288 -- This transformation not only simplifies the rest of the analysis of
14289 -- this type declaration but also simplifies the correct generation of
14290 -- the object layout to the expander.
14292 if In_Private_Part (Current_Scope)
14293 and then Is_Interface (Parent_Type)
14297 Partial_View : Entity_Id;
14298 Partial_View_Parent : Entity_Id;
14299 New_Iface : Node_Id;
14302 -- Look for the associated private type declaration
14304 Partial_View := First_Entity (Current_Scope);
14306 exit when No (Partial_View)
14307 or else (Has_Private_Declaration (Partial_View)
14308 and then Full_View (Partial_View) = T);
14310 Next_Entity (Partial_View);
14313 -- If the partial view was not found then the source code has
14314 -- errors and the transformation is not needed.
14316 if Present (Partial_View) then
14317 Partial_View_Parent := Etype (Partial_View);
14319 -- If the parent of the full-view covers the parent of the
14320 -- partial-view we have nothing else to do.
14322 if Interface_Present_In_Ancestor
14323 (Parent_Type, Partial_View_Parent)
14327 -- Traverse the list of interfaces of the full-view to look
14328 -- for the parent of the partial-view and perform the tree
14332 Iface := First (Interface_List (Def));
14333 while Present (Iface) loop
14334 if Etype (Iface) = Etype (Partial_View) then
14335 Rewrite (Subtype_Indication (Def),
14336 New_Copy (Subtype_Indication
14337 (Parent (Partial_View))));
14340 Make_Identifier (Sloc (N), Chars (Parent_Type));
14341 Append (New_Iface, Interface_List (Def));
14343 -- Analyze the transformed code
14345 Derived_Type_Declaration (T, N, Is_Completion);
14356 -- Only composite types other than array types are allowed to have
14357 -- discriminants. In SPARK, no types are allowed to have discriminants.
14359 if Present (Discriminant_Specifications (N)) then
14360 if (Is_Elementary_Type (Parent_Type)
14361 or else Is_Array_Type (Parent_Type))
14362 and then not Error_Posted (N)
14365 ("elementary or array type cannot have discriminants",
14366 Defining_Identifier (First (Discriminant_Specifications (N))));
14367 Set_Has_Discriminants (T, False);
14369 Check_SPARK_Restriction ("discriminant type is not allowed", N);
14373 -- In Ada 83, a derived type defined in a package specification cannot
14374 -- be used for further derivation until the end of its visible part.
14375 -- Note that derivation in the private part of the package is allowed.
14377 if Ada_Version = Ada_83
14378 and then Is_Derived_Type (Parent_Type)
14379 and then In_Visible_Part (Scope (Parent_Type))
14381 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
14383 ("(Ada 83): premature use of type for derivation", Indic);
14387 -- Check for early use of incomplete or private type
14389 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
14390 Error_Msg_N ("premature derivation of incomplete type", Indic);
14393 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
14394 and then not Comes_From_Generic (Parent_Type))
14395 or else Has_Private_Component (Parent_Type)
14397 -- The ancestor type of a formal type can be incomplete, in which
14398 -- case only the operations of the partial view are available in the
14399 -- generic. Subsequent checks may be required when the full view is
14400 -- analyzed to verify that a derivation from a tagged type has an
14403 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
14406 elsif No (Underlying_Type (Parent_Type))
14407 or else Has_Private_Component (Parent_Type)
14410 ("premature derivation of derived or private type", Indic);
14412 -- Flag the type itself as being in error, this prevents some
14413 -- nasty problems with subsequent uses of the malformed type.
14415 Set_Error_Posted (T);
14417 -- Check that within the immediate scope of an untagged partial
14418 -- view it's illegal to derive from the partial view if the
14419 -- full view is tagged. (7.3(7))
14421 -- We verify that the Parent_Type is a partial view by checking
14422 -- that it is not a Full_Type_Declaration (i.e. a private type or
14423 -- private extension declaration), to distinguish a partial view
14424 -- from a derivation from a private type which also appears as
14425 -- E_Private_Type. If the parent base type is not declared in an
14426 -- enclosing scope there is no need to check.
14428 elsif Present (Full_View (Parent_Type))
14429 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
14430 and then not Is_Tagged_Type (Parent_Type)
14431 and then Is_Tagged_Type (Full_View (Parent_Type))
14432 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
14435 ("premature derivation from type with tagged full view",
14440 -- Check that form of derivation is appropriate
14442 Taggd := Is_Tagged_Type (Parent_Type);
14444 -- Perhaps the parent type should be changed to the class-wide type's
14445 -- specific type in this case to prevent cascading errors ???
14447 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
14448 Error_Msg_N ("parent type must not be a class-wide type", Indic);
14452 if Present (Extension) and then not Taggd then
14454 ("type derived from untagged type cannot have extension", Indic);
14456 elsif No (Extension) and then Taggd then
14458 -- If this declaration is within a private part (or body) of a
14459 -- generic instantiation then the derivation is allowed (the parent
14460 -- type can only appear tagged in this case if it's a generic actual
14461 -- type, since it would otherwise have been rejected in the analysis
14462 -- of the generic template).
14464 if not Is_Generic_Actual_Type (Parent_Type)
14465 or else In_Visible_Part (Scope (Parent_Type))
14467 if Is_Class_Wide_Type (Parent_Type) then
14469 ("parent type must not be a class-wide type", Indic);
14471 -- Use specific type to prevent cascaded errors.
14473 Parent_Type := Etype (Parent_Type);
14477 ("type derived from tagged type must have extension", Indic);
14482 -- AI-443: Synchronized formal derived types require a private
14483 -- extension. There is no point in checking the ancestor type or
14484 -- the progenitors since the construct is wrong to begin with.
14486 if Ada_Version >= Ada_2005
14487 and then Is_Generic_Type (T)
14488 and then Present (Original_Node (N))
14491 Decl : constant Node_Id := Original_Node (N);
14494 if Nkind (Decl) = N_Formal_Type_Declaration
14495 and then Nkind (Formal_Type_Definition (Decl)) =
14496 N_Formal_Derived_Type_Definition
14497 and then Synchronized_Present (Formal_Type_Definition (Decl))
14498 and then No (Extension)
14500 -- Avoid emitting a duplicate error message
14502 and then not Error_Posted (Indic)
14505 ("synchronized derived type must have extension", N);
14510 if Null_Exclusion_Present (Def)
14511 and then not Is_Access_Type (Parent_Type)
14513 Error_Msg_N ("null exclusion can only apply to an access type", N);
14516 -- Avoid deriving parent primitives of underlying record views
14518 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
14519 Derive_Subps => not Is_Underlying_Record_View (T));
14521 -- AI-419: The parent type of an explicitly limited derived type must
14522 -- be a limited type or a limited interface.
14524 if Limited_Present (Def) then
14525 Set_Is_Limited_Record (T);
14527 if Is_Interface (T) then
14528 Set_Is_Limited_Interface (T);
14531 if not Is_Limited_Type (Parent_Type)
14533 (not Is_Interface (Parent_Type)
14534 or else not Is_Limited_Interface (Parent_Type))
14536 -- AI05-0096: a derivation in the private part of an instance is
14537 -- legal if the generic formal is untagged limited, and the actual
14540 if Is_Generic_Actual_Type (Parent_Type)
14541 and then In_Private_Part (Current_Scope)
14544 (Generic_Parent_Type (Parent (Parent_Type)))
14550 ("parent type& of limited type must be limited",
14556 -- In SPARK, there are no derived type definitions other than type
14557 -- extensions of tagged record types.
14559 if No (Extension) then
14560 Check_SPARK_Restriction ("derived type is not allowed", N);
14562 end Derived_Type_Declaration;
14564 ------------------------
14565 -- Diagnose_Interface --
14566 ------------------------
14568 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
14570 if not Is_Interface (E)
14571 and then E /= Any_Type
14573 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
14575 end Diagnose_Interface;
14577 ----------------------------------
14578 -- Enumeration_Type_Declaration --
14579 ----------------------------------
14581 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
14588 -- Create identifier node representing lower bound
14590 B_Node := New_Node (N_Identifier, Sloc (Def));
14591 L := First (Literals (Def));
14592 Set_Chars (B_Node, Chars (L));
14593 Set_Entity (B_Node, L);
14594 Set_Etype (B_Node, T);
14595 Set_Is_Static_Expression (B_Node, True);
14597 R_Node := New_Node (N_Range, Sloc (Def));
14598 Set_Low_Bound (R_Node, B_Node);
14600 Set_Ekind (T, E_Enumeration_Type);
14601 Set_First_Literal (T, L);
14603 Set_Is_Constrained (T);
14607 -- Loop through literals of enumeration type setting pos and rep values
14608 -- except that if the Ekind is already set, then it means the literal
14609 -- was already constructed (case of a derived type declaration and we
14610 -- should not disturb the Pos and Rep values.
14612 while Present (L) loop
14613 if Ekind (L) /= E_Enumeration_Literal then
14614 Set_Ekind (L, E_Enumeration_Literal);
14615 Set_Enumeration_Pos (L, Ev);
14616 Set_Enumeration_Rep (L, Ev);
14617 Set_Is_Known_Valid (L, True);
14621 New_Overloaded_Entity (L);
14622 Generate_Definition (L);
14623 Set_Convention (L, Convention_Intrinsic);
14625 -- Case of character literal
14627 if Nkind (L) = N_Defining_Character_Literal then
14628 Set_Is_Character_Type (T, True);
14630 -- Check violation of No_Wide_Characters
14632 if Restriction_Check_Required (No_Wide_Characters) then
14633 Get_Name_String (Chars (L));
14635 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
14636 Check_Restriction (No_Wide_Characters, L);
14645 -- Now create a node representing upper bound
14647 B_Node := New_Node (N_Identifier, Sloc (Def));
14648 Set_Chars (B_Node, Chars (Last (Literals (Def))));
14649 Set_Entity (B_Node, Last (Literals (Def)));
14650 Set_Etype (B_Node, T);
14651 Set_Is_Static_Expression (B_Node, True);
14653 Set_High_Bound (R_Node, B_Node);
14655 -- Initialize various fields of the type. Some of this information
14656 -- may be overwritten later through rep.clauses.
14658 Set_Scalar_Range (T, R_Node);
14659 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
14660 Set_Enum_Esize (T);
14661 Set_Enum_Pos_To_Rep (T, Empty);
14663 -- Set Discard_Names if configuration pragma set, or if there is
14664 -- a parameterless pragma in the current declarative region
14666 if Global_Discard_Names
14667 or else Discard_Names (Scope (T))
14669 Set_Discard_Names (T);
14672 -- Process end label if there is one
14674 if Present (Def) then
14675 Process_End_Label (Def, 'e', T);
14677 end Enumeration_Type_Declaration;
14679 ---------------------------------
14680 -- Expand_To_Stored_Constraint --
14681 ---------------------------------
14683 function Expand_To_Stored_Constraint
14685 Constraint : Elist_Id) return Elist_Id
14687 Explicitly_Discriminated_Type : Entity_Id;
14688 Expansion : Elist_Id;
14689 Discriminant : Entity_Id;
14691 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
14692 -- Find the nearest type that actually specifies discriminants
14694 ---------------------------------
14695 -- Type_With_Explicit_Discrims --
14696 ---------------------------------
14698 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
14699 Typ : constant E := Base_Type (Id);
14702 if Ekind (Typ) in Incomplete_Or_Private_Kind then
14703 if Present (Full_View (Typ)) then
14704 return Type_With_Explicit_Discrims (Full_View (Typ));
14708 if Has_Discriminants (Typ) then
14713 if Etype (Typ) = Typ then
14715 elsif Has_Discriminants (Typ) then
14718 return Type_With_Explicit_Discrims (Etype (Typ));
14721 end Type_With_Explicit_Discrims;
14723 -- Start of processing for Expand_To_Stored_Constraint
14727 or else Is_Empty_Elmt_List (Constraint)
14732 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
14734 if No (Explicitly_Discriminated_Type) then
14738 Expansion := New_Elmt_List;
14741 First_Stored_Discriminant (Explicitly_Discriminated_Type);
14742 while Present (Discriminant) loop
14744 Get_Discriminant_Value (
14745 Discriminant, Explicitly_Discriminated_Type, Constraint),
14747 Next_Stored_Discriminant (Discriminant);
14751 end Expand_To_Stored_Constraint;
14753 ---------------------------
14754 -- Find_Hidden_Interface --
14755 ---------------------------
14757 function Find_Hidden_Interface
14759 Dest : Elist_Id) return Entity_Id
14762 Iface_Elmt : Elmt_Id;
14765 if Present (Src) and then Present (Dest) then
14766 Iface_Elmt := First_Elmt (Src);
14767 while Present (Iface_Elmt) loop
14768 Iface := Node (Iface_Elmt);
14770 if Is_Interface (Iface)
14771 and then not Contain_Interface (Iface, Dest)
14776 Next_Elmt (Iface_Elmt);
14781 end Find_Hidden_Interface;
14783 --------------------
14784 -- Find_Type_Name --
14785 --------------------
14787 function Find_Type_Name (N : Node_Id) return Entity_Id is
14788 Id : constant Entity_Id := Defining_Identifier (N);
14790 New_Id : Entity_Id;
14791 Prev_Par : Node_Id;
14793 procedure Tag_Mismatch;
14794 -- Diagnose a tagged partial view whose full view is untagged.
14795 -- We post the message on the full view, with a reference to
14796 -- the previous partial view. The partial view can be private
14797 -- or incomplete, and these are handled in a different manner,
14798 -- so we determine the position of the error message from the
14799 -- respective slocs of both.
14805 procedure Tag_Mismatch is
14807 if Sloc (Prev) < Sloc (Id) then
14808 if Ada_Version >= Ada_2012
14809 and then Nkind (N) = N_Private_Type_Declaration
14812 ("declaration of private } must be a tagged type ", Id, Prev);
14815 ("full declaration of } must be a tagged type ", Id, Prev);
14818 if Ada_Version >= Ada_2012
14819 and then Nkind (N) = N_Private_Type_Declaration
14822 ("declaration of private } must be a tagged type ", Prev, Id);
14825 ("full declaration of } must be a tagged type ", Prev, Id);
14830 -- Start of processing for Find_Type_Name
14833 -- Find incomplete declaration, if one was given
14835 Prev := Current_Entity_In_Scope (Id);
14837 -- New type declaration
14843 -- Previous declaration exists
14846 Prev_Par := Parent (Prev);
14848 -- Error if not incomplete/private case except if previous
14849 -- declaration is implicit, etc. Enter_Name will emit error if
14852 if not Is_Incomplete_Or_Private_Type (Prev) then
14856 -- Check invalid completion of private or incomplete type
14858 elsif not Nkind_In (N, N_Full_Type_Declaration,
14859 N_Task_Type_Declaration,
14860 N_Protected_Type_Declaration)
14862 (Ada_Version < Ada_2012
14863 or else not Is_Incomplete_Type (Prev)
14864 or else not Nkind_In (N, N_Private_Type_Declaration,
14865 N_Private_Extension_Declaration))
14867 -- Completion must be a full type declarations (RM 7.3(4))
14869 Error_Msg_Sloc := Sloc (Prev);
14870 Error_Msg_NE ("invalid completion of }", Id, Prev);
14872 -- Set scope of Id to avoid cascaded errors. Entity is never
14873 -- examined again, except when saving globals in generics.
14875 Set_Scope (Id, Current_Scope);
14878 -- If this is a repeated incomplete declaration, no further
14879 -- checks are possible.
14881 if Nkind (N) = N_Incomplete_Type_Declaration then
14885 -- Case of full declaration of incomplete type
14887 elsif Ekind (Prev) = E_Incomplete_Type
14888 and then (Ada_Version < Ada_2012
14889 or else No (Full_View (Prev))
14890 or else not Is_Private_Type (Full_View (Prev)))
14893 -- Indicate that the incomplete declaration has a matching full
14894 -- declaration. The defining occurrence of the incomplete
14895 -- declaration remains the visible one, and the procedure
14896 -- Get_Full_View dereferences it whenever the type is used.
14898 if Present (Full_View (Prev)) then
14899 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
14902 Set_Full_View (Prev, Id);
14903 Append_Entity (Id, Current_Scope);
14904 Set_Is_Public (Id, Is_Public (Prev));
14905 Set_Is_Internal (Id);
14908 -- If the incomplete view is tagged, a class_wide type has been
14909 -- created already. Use it for the private type as well, in order
14910 -- to prevent multiple incompatible class-wide types that may be
14911 -- created for self-referential anonymous access components.
14913 if Is_Tagged_Type (Prev)
14914 and then Present (Class_Wide_Type (Prev))
14916 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
14917 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
14918 Set_Etype (Class_Wide_Type (Id), Id);
14921 -- Case of full declaration of private type
14924 -- If the private type was a completion of an incomplete type then
14925 -- update Prev to reference the private type
14927 if Ada_Version >= Ada_2012
14928 and then Ekind (Prev) = E_Incomplete_Type
14929 and then Present (Full_View (Prev))
14930 and then Is_Private_Type (Full_View (Prev))
14932 Prev := Full_View (Prev);
14933 Prev_Par := Parent (Prev);
14936 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
14937 if Etype (Prev) /= Prev then
14939 -- Prev is a private subtype or a derived type, and needs
14942 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
14945 elsif Ekind (Prev) = E_Private_Type
14946 and then Nkind_In (N, N_Task_Type_Declaration,
14947 N_Protected_Type_Declaration)
14950 ("completion of nonlimited type cannot be limited", N);
14952 elsif Ekind (Prev) = E_Record_Type_With_Private
14953 and then Nkind_In (N, N_Task_Type_Declaration,
14954 N_Protected_Type_Declaration)
14956 if not Is_Limited_Record (Prev) then
14958 ("completion of nonlimited type cannot be limited", N);
14960 elsif No (Interface_List (N)) then
14962 ("completion of tagged private type must be tagged",
14966 elsif Nkind (N) = N_Full_Type_Declaration
14968 Nkind (Type_Definition (N)) = N_Record_Definition
14969 and then Interface_Present (Type_Definition (N))
14972 ("completion of private type cannot be an interface", N);
14975 -- Ada 2005 (AI-251): Private extension declaration of a task
14976 -- type or a protected type. This case arises when covering
14977 -- interface types.
14979 elsif Nkind_In (N, N_Task_Type_Declaration,
14980 N_Protected_Type_Declaration)
14984 elsif Nkind (N) /= N_Full_Type_Declaration
14985 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
14988 ("full view of private extension must be an extension", N);
14990 elsif not (Abstract_Present (Parent (Prev)))
14991 and then Abstract_Present (Type_Definition (N))
14994 ("full view of non-abstract extension cannot be abstract", N);
14997 if not In_Private_Part (Current_Scope) then
14999 ("declaration of full view must appear in private part", N);
15002 Copy_And_Swap (Prev, Id);
15003 Set_Has_Private_Declaration (Prev);
15004 Set_Has_Private_Declaration (Id);
15006 -- Preserve aspect and iterator flags that may have been set on
15007 -- the partial view.
15009 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
15010 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
15012 -- If no error, propagate freeze_node from private to full view.
15013 -- It may have been generated for an early operational item.
15015 if Present (Freeze_Node (Id))
15016 and then Serious_Errors_Detected = 0
15017 and then No (Full_View (Id))
15019 Set_Freeze_Node (Prev, Freeze_Node (Id));
15020 Set_Freeze_Node (Id, Empty);
15021 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
15024 Set_Full_View (Id, Prev);
15028 -- Verify that full declaration conforms to partial one
15030 if Is_Incomplete_Or_Private_Type (Prev)
15031 and then Present (Discriminant_Specifications (Prev_Par))
15033 if Present (Discriminant_Specifications (N)) then
15034 if Ekind (Prev) = E_Incomplete_Type then
15035 Check_Discriminant_Conformance (N, Prev, Prev);
15037 Check_Discriminant_Conformance (N, Prev, Id);
15042 ("missing discriminants in full type declaration", N);
15044 -- To avoid cascaded errors on subsequent use, share the
15045 -- discriminants of the partial view.
15047 Set_Discriminant_Specifications (N,
15048 Discriminant_Specifications (Prev_Par));
15052 -- A prior untagged partial view can have an associated class-wide
15053 -- type due to use of the class attribute, and in this case the full
15054 -- type must also be tagged. This Ada 95 usage is deprecated in favor
15055 -- of incomplete tagged declarations, but we check for it.
15058 and then (Is_Tagged_Type (Prev)
15059 or else Present (Class_Wide_Type (Prev)))
15061 -- Ada 2012 (AI05-0162): A private type may be the completion of
15062 -- an incomplete type
15064 if Ada_Version >= Ada_2012
15065 and then Is_Incomplete_Type (Prev)
15066 and then Nkind_In (N, N_Private_Type_Declaration,
15067 N_Private_Extension_Declaration)
15069 -- No need to check private extensions since they are tagged
15071 if Nkind (N) = N_Private_Type_Declaration
15072 and then not Tagged_Present (N)
15077 -- The full declaration is either a tagged type (including
15078 -- a synchronized type that implements interfaces) or a
15079 -- type extension, otherwise this is an error.
15081 elsif Nkind_In (N, N_Task_Type_Declaration,
15082 N_Protected_Type_Declaration)
15084 if No (Interface_List (N))
15085 and then not Error_Posted (N)
15090 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
15092 -- Indicate that the previous declaration (tagged incomplete
15093 -- or private declaration) requires the same on the full one.
15095 if not Tagged_Present (Type_Definition (N)) then
15097 Set_Is_Tagged_Type (Id);
15100 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
15101 if No (Record_Extension_Part (Type_Definition (N))) then
15103 ("full declaration of } must be a record extension",
15106 -- Set some attributes to produce a usable full view
15108 Set_Is_Tagged_Type (Id);
15117 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
15118 and then Present (Premature_Use (Parent (Prev)))
15120 Error_Msg_Sloc := Sloc (N);
15122 ("\full declaration #", Premature_Use (Parent (Prev)));
15127 end Find_Type_Name;
15129 -------------------------
15130 -- Find_Type_Of_Object --
15131 -------------------------
15133 function Find_Type_Of_Object
15134 (Obj_Def : Node_Id;
15135 Related_Nod : Node_Id) return Entity_Id
15137 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
15138 P : Node_Id := Parent (Obj_Def);
15143 -- If the parent is a component_definition node we climb to the
15144 -- component_declaration node
15146 if Nkind (P) = N_Component_Definition then
15150 -- Case of an anonymous array subtype
15152 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
15153 N_Unconstrained_Array_Definition)
15156 Array_Type_Declaration (T, Obj_Def);
15158 -- Create an explicit subtype whenever possible
15160 elsif Nkind (P) /= N_Component_Declaration
15161 and then Def_Kind = N_Subtype_Indication
15163 -- Base name of subtype on object name, which will be unique in
15164 -- the current scope.
15166 -- If this is a duplicate declaration, return base type, to avoid
15167 -- generating duplicate anonymous types.
15169 if Error_Posted (P) then
15170 Analyze (Subtype_Mark (Obj_Def));
15171 return Entity (Subtype_Mark (Obj_Def));
15176 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
15178 T := Make_Defining_Identifier (Sloc (P), Nam);
15180 Insert_Action (Obj_Def,
15181 Make_Subtype_Declaration (Sloc (P),
15182 Defining_Identifier => T,
15183 Subtype_Indication => Relocate_Node (Obj_Def)));
15185 -- This subtype may need freezing, and this will not be done
15186 -- automatically if the object declaration is not in declarative
15187 -- part. Since this is an object declaration, the type cannot always
15188 -- be frozen here. Deferred constants do not freeze their type
15189 -- (which often enough will be private).
15191 if Nkind (P) = N_Object_Declaration
15192 and then Constant_Present (P)
15193 and then No (Expression (P))
15197 Insert_Actions (Obj_Def, Freeze_Entity (T, P));
15200 -- Ada 2005 AI-406: the object definition in an object declaration
15201 -- can be an access definition.
15203 elsif Def_Kind = N_Access_Definition then
15204 T := Access_Definition (Related_Nod, Obj_Def);
15206 Set_Is_Local_Anonymous_Access
15208 V => (Ada_Version < Ada_2012)
15209 or else (Nkind (P) /= N_Object_Declaration)
15210 or else Is_Library_Level_Entity (Defining_Identifier (P)));
15212 -- Otherwise, the object definition is just a subtype_mark
15215 T := Process_Subtype (Obj_Def, Related_Nod);
15217 -- If expansion is disabled an object definition that is an aggregate
15218 -- will not get expanded and may lead to scoping problems in the back
15219 -- end, if the object is referenced in an inner scope. In that case
15220 -- create an itype reference for the object definition now. This
15221 -- may be redundant in some cases, but harmless.
15224 and then Nkind (Related_Nod) = N_Object_Declaration
15227 Build_Itype_Reference (T, Related_Nod);
15232 end Find_Type_Of_Object;
15234 --------------------------------
15235 -- Find_Type_Of_Subtype_Indic --
15236 --------------------------------
15238 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
15242 -- Case of subtype mark with a constraint
15244 if Nkind (S) = N_Subtype_Indication then
15245 Find_Type (Subtype_Mark (S));
15246 Typ := Entity (Subtype_Mark (S));
15249 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
15252 ("incorrect constraint for this kind of type", Constraint (S));
15253 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
15256 -- Otherwise we have a subtype mark without a constraint
15258 elsif Error_Posted (S) then
15259 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
15267 -- Check No_Wide_Characters restriction
15269 Check_Wide_Character_Restriction (Typ, S);
15272 end Find_Type_Of_Subtype_Indic;
15274 -------------------------------------
15275 -- Floating_Point_Type_Declaration --
15276 -------------------------------------
15278 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
15279 Digs : constant Node_Id := Digits_Expression (Def);
15280 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
15282 Base_Typ : Entity_Id;
15283 Implicit_Base : Entity_Id;
15286 function Can_Derive_From (E : Entity_Id) return Boolean;
15287 -- Find if given digits value, and possibly a specified range, allows
15288 -- derivation from specified type
15290 function Find_Base_Type return Entity_Id;
15291 -- Find a predefined base type that Def can derive from, or generate
15292 -- an error and substitute Long_Long_Float if none exists.
15294 ---------------------
15295 -- Can_Derive_From --
15296 ---------------------
15298 function Can_Derive_From (E : Entity_Id) return Boolean is
15299 Spec : constant Entity_Id := Real_Range_Specification (Def);
15302 if Digs_Val > Digits_Value (E) then
15306 if Present (Spec) then
15307 if Expr_Value_R (Type_Low_Bound (E)) >
15308 Expr_Value_R (Low_Bound (Spec))
15313 if Expr_Value_R (Type_High_Bound (E)) <
15314 Expr_Value_R (High_Bound (Spec))
15321 end Can_Derive_From;
15323 --------------------
15324 -- Find_Base_Type --
15325 --------------------
15327 function Find_Base_Type return Entity_Id is
15328 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
15331 -- Iterate over the predefined types in order, returning the first
15332 -- one that Def can derive from.
15334 while Present (Choice) loop
15335 if Can_Derive_From (Node (Choice)) then
15336 return Node (Choice);
15339 Next_Elmt (Choice);
15342 -- If we can't derive from any existing type, use Long_Long_Float
15343 -- and give appropriate message explaining the problem.
15345 if Digs_Val > Max_Digs_Val then
15346 -- It might be the case that there is a type with the requested
15347 -- range, just not the combination of digits and range.
15350 ("no predefined type has requested range and precision",
15351 Real_Range_Specification (Def));
15355 ("range too large for any predefined type",
15356 Real_Range_Specification (Def));
15359 return Standard_Long_Long_Float;
15360 end Find_Base_Type;
15362 -- Start of processing for Floating_Point_Type_Declaration
15365 Check_Restriction (No_Floating_Point, Def);
15367 -- Create an implicit base type
15370 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
15372 -- Analyze and verify digits value
15374 Analyze_And_Resolve (Digs, Any_Integer);
15375 Check_Digits_Expression (Digs);
15376 Digs_Val := Expr_Value (Digs);
15378 -- Process possible range spec and find correct type to derive from
15380 Process_Real_Range_Specification (Def);
15382 -- Check that requested number of digits is not too high.
15384 if Digs_Val > Max_Digs_Val then
15385 -- The check for Max_Base_Digits may be somewhat expensive, as it
15386 -- requires reading System, so only do it when necessary.
15389 Max_Base_Digits : constant Uint :=
15392 (Parent (RTE (RE_Max_Base_Digits))));
15395 if Digs_Val > Max_Base_Digits then
15396 Error_Msg_Uint_1 := Max_Base_Digits;
15397 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
15399 elsif No (Real_Range_Specification (Def)) then
15400 Error_Msg_Uint_1 := Max_Digs_Val;
15401 Error_Msg_N ("types with more than ^ digits need range spec "
15402 & "(RM 3.5.7(6))", Digs);
15407 -- Find a suitable type to derive from or complain and use a substitute
15409 Base_Typ := Find_Base_Type;
15411 -- If there are bounds given in the declaration use them as the bounds
15412 -- of the type, otherwise use the bounds of the predefined base type
15413 -- that was chosen based on the Digits value.
15415 if Present (Real_Range_Specification (Def)) then
15416 Set_Scalar_Range (T, Real_Range_Specification (Def));
15417 Set_Is_Constrained (T);
15419 -- The bounds of this range must be converted to machine numbers
15420 -- in accordance with RM 4.9(38).
15422 Bound := Type_Low_Bound (T);
15424 if Nkind (Bound) = N_Real_Literal then
15426 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
15427 Set_Is_Machine_Number (Bound);
15430 Bound := Type_High_Bound (T);
15432 if Nkind (Bound) = N_Real_Literal then
15434 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
15435 Set_Is_Machine_Number (Bound);
15439 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
15442 -- Complete definition of implicit base and declared first subtype
15444 Set_Etype (Implicit_Base, Base_Typ);
15446 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
15447 Set_Size_Info (Implicit_Base, (Base_Typ));
15448 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
15449 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
15450 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
15451 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
15453 Set_Ekind (T, E_Floating_Point_Subtype);
15454 Set_Etype (T, Implicit_Base);
15456 Set_Size_Info (T, (Implicit_Base));
15457 Set_RM_Size (T, RM_Size (Implicit_Base));
15458 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
15459 Set_Digits_Value (T, Digs_Val);
15460 end Floating_Point_Type_Declaration;
15462 ----------------------------
15463 -- Get_Discriminant_Value --
15464 ----------------------------
15466 -- This is the situation:
15468 -- There is a non-derived type
15470 -- type T0 (Dx, Dy, Dz...)
15472 -- There are zero or more levels of derivation, with each derivation
15473 -- either purely inheriting the discriminants, or defining its own.
15475 -- type Ti is new Ti-1
15477 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
15479 -- subtype Ti is ...
15481 -- The subtype issue is avoided by the use of Original_Record_Component,
15482 -- and the fact that derived subtypes also derive the constraints.
15484 -- This chain leads back from
15486 -- Typ_For_Constraint
15488 -- Typ_For_Constraint has discriminants, and the value for each
15489 -- discriminant is given by its corresponding Elmt of Constraints.
15491 -- Discriminant is some discriminant in this hierarchy
15493 -- We need to return its value
15495 -- We do this by recursively searching each level, and looking for
15496 -- Discriminant. Once we get to the bottom, we start backing up
15497 -- returning the value for it which may in turn be a discriminant
15498 -- further up, so on the backup we continue the substitution.
15500 function Get_Discriminant_Value
15501 (Discriminant : Entity_Id;
15502 Typ_For_Constraint : Entity_Id;
15503 Constraint : Elist_Id) return Node_Id
15505 function Search_Derivation_Levels
15507 Discrim_Values : Elist_Id;
15508 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
15509 -- This is the routine that performs the recursive search of levels
15510 -- as described above.
15512 ------------------------------
15513 -- Search_Derivation_Levels --
15514 ------------------------------
15516 function Search_Derivation_Levels
15518 Discrim_Values : Elist_Id;
15519 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
15523 Result : Node_Or_Entity_Id;
15524 Result_Entity : Node_Id;
15527 -- If inappropriate type, return Error, this happens only in
15528 -- cascaded error situations, and we want to avoid a blow up.
15530 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
15534 -- Look deeper if possible. Use Stored_Constraints only for
15535 -- untagged types. For tagged types use the given constraint.
15536 -- This asymmetry needs explanation???
15538 if not Stored_Discrim_Values
15539 and then Present (Stored_Constraint (Ti))
15540 and then not Is_Tagged_Type (Ti)
15543 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
15546 Td : constant Entity_Id := Etype (Ti);
15550 Result := Discriminant;
15553 if Present (Stored_Constraint (Ti)) then
15555 Search_Derivation_Levels
15556 (Td, Stored_Constraint (Ti), True);
15559 Search_Derivation_Levels
15560 (Td, Discrim_Values, Stored_Discrim_Values);
15566 -- Extra underlying places to search, if not found above. For
15567 -- concurrent types, the relevant discriminant appears in the
15568 -- corresponding record. For a type derived from a private type
15569 -- without discriminant, the full view inherits the discriminants
15570 -- of the full view of the parent.
15572 if Result = Discriminant then
15573 if Is_Concurrent_Type (Ti)
15574 and then Present (Corresponding_Record_Type (Ti))
15577 Search_Derivation_Levels (
15578 Corresponding_Record_Type (Ti),
15580 Stored_Discrim_Values);
15582 elsif Is_Private_Type (Ti)
15583 and then not Has_Discriminants (Ti)
15584 and then Present (Full_View (Ti))
15585 and then Etype (Full_View (Ti)) /= Ti
15588 Search_Derivation_Levels (
15591 Stored_Discrim_Values);
15595 -- If Result is not a (reference to a) discriminant, return it,
15596 -- otherwise set Result_Entity to the discriminant.
15598 if Nkind (Result) = N_Defining_Identifier then
15599 pragma Assert (Result = Discriminant);
15600 Result_Entity := Result;
15603 if not Denotes_Discriminant (Result) then
15607 Result_Entity := Entity (Result);
15610 -- See if this level of derivation actually has discriminants
15611 -- because tagged derivations can add them, hence the lower
15612 -- levels need not have any.
15614 if not Has_Discriminants (Ti) then
15618 -- Scan Ti's discriminants for Result_Entity,
15619 -- and return its corresponding value, if any.
15621 Result_Entity := Original_Record_Component (Result_Entity);
15623 Assoc := First_Elmt (Discrim_Values);
15625 if Stored_Discrim_Values then
15626 Disc := First_Stored_Discriminant (Ti);
15628 Disc := First_Discriminant (Ti);
15631 while Present (Disc) loop
15632 pragma Assert (Present (Assoc));
15634 if Original_Record_Component (Disc) = Result_Entity then
15635 return Node (Assoc);
15640 if Stored_Discrim_Values then
15641 Next_Stored_Discriminant (Disc);
15643 Next_Discriminant (Disc);
15647 -- Could not find it
15650 end Search_Derivation_Levels;
15654 Result : Node_Or_Entity_Id;
15656 -- Start of processing for Get_Discriminant_Value
15659 -- ??? This routine is a gigantic mess and will be deleted. For the
15660 -- time being just test for the trivial case before calling recurse.
15662 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
15668 D := First_Discriminant (Typ_For_Constraint);
15669 E := First_Elmt (Constraint);
15670 while Present (D) loop
15671 if Chars (D) = Chars (Discriminant) then
15675 Next_Discriminant (D);
15681 Result := Search_Derivation_Levels
15682 (Typ_For_Constraint, Constraint, False);
15684 -- ??? hack to disappear when this routine is gone
15686 if Nkind (Result) = N_Defining_Identifier then
15692 D := First_Discriminant (Typ_For_Constraint);
15693 E := First_Elmt (Constraint);
15694 while Present (D) loop
15695 if Corresponding_Discriminant (D) = Discriminant then
15699 Next_Discriminant (D);
15705 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
15707 end Get_Discriminant_Value;
15709 --------------------------
15710 -- Has_Range_Constraint --
15711 --------------------------
15713 function Has_Range_Constraint (N : Node_Id) return Boolean is
15714 C : constant Node_Id := Constraint (N);
15717 if Nkind (C) = N_Range_Constraint then
15720 elsif Nkind (C) = N_Digits_Constraint then
15722 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
15724 Present (Range_Constraint (C));
15726 elsif Nkind (C) = N_Delta_Constraint then
15727 return Present (Range_Constraint (C));
15732 end Has_Range_Constraint;
15734 ------------------------
15735 -- Inherit_Components --
15736 ------------------------
15738 function Inherit_Components
15740 Parent_Base : Entity_Id;
15741 Derived_Base : Entity_Id;
15742 Is_Tagged : Boolean;
15743 Inherit_Discr : Boolean;
15744 Discs : Elist_Id) return Elist_Id
15746 Assoc_List : constant Elist_Id := New_Elmt_List;
15748 procedure Inherit_Component
15749 (Old_C : Entity_Id;
15750 Plain_Discrim : Boolean := False;
15751 Stored_Discrim : Boolean := False);
15752 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
15753 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
15754 -- True, Old_C is a stored discriminant. If they are both false then
15755 -- Old_C is a regular component.
15757 -----------------------
15758 -- Inherit_Component --
15759 -----------------------
15761 procedure Inherit_Component
15762 (Old_C : Entity_Id;
15763 Plain_Discrim : Boolean := False;
15764 Stored_Discrim : Boolean := False)
15766 procedure Set_Anonymous_Type (Id : Entity_Id);
15767 -- Id denotes the entity of an access discriminant or anonymous
15768 -- access component. Set the type of Id to either the same type of
15769 -- Old_C or create a new one depending on whether the parent and
15770 -- the child types are in the same scope.
15772 ------------------------
15773 -- Set_Anonymous_Type --
15774 ------------------------
15776 procedure Set_Anonymous_Type (Id : Entity_Id) is
15777 Old_Typ : constant Entity_Id := Etype (Old_C);
15780 if Scope (Parent_Base) = Scope (Derived_Base) then
15781 Set_Etype (Id, Old_Typ);
15783 -- The parent and the derived type are in two different scopes.
15784 -- Reuse the type of the original discriminant / component by
15785 -- copying it in order to preserve all attributes.
15789 Typ : constant Entity_Id := New_Copy (Old_Typ);
15792 Set_Etype (Id, Typ);
15794 -- Since we do not generate component declarations for
15795 -- inherited components, associate the itype with the
15798 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
15799 Set_Scope (Typ, Derived_Base);
15802 end Set_Anonymous_Type;
15804 -- Local variables and constants
15806 New_C : constant Entity_Id := New_Copy (Old_C);
15808 Corr_Discrim : Entity_Id;
15809 Discrim : Entity_Id;
15811 -- Start of processing for Inherit_Component
15814 pragma Assert (not Is_Tagged or else not Stored_Discrim);
15816 Set_Parent (New_C, Parent (Old_C));
15818 -- Regular discriminants and components must be inserted in the scope
15819 -- of the Derived_Base. Do it here.
15821 if not Stored_Discrim then
15822 Enter_Name (New_C);
15825 -- For tagged types the Original_Record_Component must point to
15826 -- whatever this field was pointing to in the parent type. This has
15827 -- already been achieved by the call to New_Copy above.
15829 if not Is_Tagged then
15830 Set_Original_Record_Component (New_C, New_C);
15833 -- Set the proper type of an access discriminant
15835 if Ekind (New_C) = E_Discriminant
15836 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
15838 Set_Anonymous_Type (New_C);
15841 -- If we have inherited a component then see if its Etype contains
15842 -- references to Parent_Base discriminants. In this case, replace
15843 -- these references with the constraints given in Discs. We do not
15844 -- do this for the partial view of private types because this is
15845 -- not needed (only the components of the full view will be used
15846 -- for code generation) and cause problem. We also avoid this
15847 -- transformation in some error situations.
15849 if Ekind (New_C) = E_Component then
15851 -- Set the proper type of an anonymous access component
15853 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
15854 Set_Anonymous_Type (New_C);
15856 elsif (Is_Private_Type (Derived_Base)
15857 and then not Is_Generic_Type (Derived_Base))
15858 or else (Is_Empty_Elmt_List (Discs)
15859 and then not Expander_Active)
15861 Set_Etype (New_C, Etype (Old_C));
15864 -- The current component introduces a circularity of the
15867 -- limited with Pack_2;
15868 -- package Pack_1 is
15869 -- type T_1 is tagged record
15870 -- Comp : access Pack_2.T_2;
15876 -- package Pack_2 is
15877 -- type T_2 is new Pack_1.T_1 with ...;
15882 Constrain_Component_Type
15883 (Old_C, Derived_Base, N, Parent_Base, Discs));
15887 -- In derived tagged types it is illegal to reference a non
15888 -- discriminant component in the parent type. To catch this, mark
15889 -- these components with an Ekind of E_Void. This will be reset in
15890 -- Record_Type_Definition after processing the record extension of
15891 -- the derived type.
15893 -- If the declaration is a private extension, there is no further
15894 -- record extension to process, and the components retain their
15895 -- current kind, because they are visible at this point.
15897 if Is_Tagged and then Ekind (New_C) = E_Component
15898 and then Nkind (N) /= N_Private_Extension_Declaration
15900 Set_Ekind (New_C, E_Void);
15903 if Plain_Discrim then
15904 Set_Corresponding_Discriminant (New_C, Old_C);
15905 Build_Discriminal (New_C);
15907 -- If we are explicitly inheriting a stored discriminant it will be
15908 -- completely hidden.
15910 elsif Stored_Discrim then
15911 Set_Corresponding_Discriminant (New_C, Empty);
15912 Set_Discriminal (New_C, Empty);
15913 Set_Is_Completely_Hidden (New_C);
15915 -- Set the Original_Record_Component of each discriminant in the
15916 -- derived base to point to the corresponding stored that we just
15919 Discrim := First_Discriminant (Derived_Base);
15920 while Present (Discrim) loop
15921 Corr_Discrim := Corresponding_Discriminant (Discrim);
15923 -- Corr_Discrim could be missing in an error situation
15925 if Present (Corr_Discrim)
15926 and then Original_Record_Component (Corr_Discrim) = Old_C
15928 Set_Original_Record_Component (Discrim, New_C);
15931 Next_Discriminant (Discrim);
15934 Append_Entity (New_C, Derived_Base);
15937 if not Is_Tagged then
15938 Append_Elmt (Old_C, Assoc_List);
15939 Append_Elmt (New_C, Assoc_List);
15941 end Inherit_Component;
15943 -- Variables local to Inherit_Component
15945 Loc : constant Source_Ptr := Sloc (N);
15947 Parent_Discrim : Entity_Id;
15948 Stored_Discrim : Entity_Id;
15950 Component : Entity_Id;
15952 -- Start of processing for Inherit_Components
15955 if not Is_Tagged then
15956 Append_Elmt (Parent_Base, Assoc_List);
15957 Append_Elmt (Derived_Base, Assoc_List);
15960 -- Inherit parent discriminants if needed
15962 if Inherit_Discr then
15963 Parent_Discrim := First_Discriminant (Parent_Base);
15964 while Present (Parent_Discrim) loop
15965 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
15966 Next_Discriminant (Parent_Discrim);
15970 -- Create explicit stored discrims for untagged types when necessary
15972 if not Has_Unknown_Discriminants (Derived_Base)
15973 and then Has_Discriminants (Parent_Base)
15974 and then not Is_Tagged
15977 or else First_Discriminant (Parent_Base) /=
15978 First_Stored_Discriminant (Parent_Base))
15980 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
15981 while Present (Stored_Discrim) loop
15982 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
15983 Next_Stored_Discriminant (Stored_Discrim);
15987 -- See if we can apply the second transformation for derived types, as
15988 -- explained in point 6. in the comments above Build_Derived_Record_Type
15989 -- This is achieved by appending Derived_Base discriminants into Discs,
15990 -- which has the side effect of returning a non empty Discs list to the
15991 -- caller of Inherit_Components, which is what we want. This must be
15992 -- done for private derived types if there are explicit stored
15993 -- discriminants, to ensure that we can retrieve the values of the
15994 -- constraints provided in the ancestors.
15997 and then Is_Empty_Elmt_List (Discs)
15998 and then Present (First_Discriminant (Derived_Base))
16000 (not Is_Private_Type (Derived_Base)
16001 or else Is_Completely_Hidden
16002 (First_Stored_Discriminant (Derived_Base))
16003 or else Is_Generic_Type (Derived_Base))
16005 D := First_Discriminant (Derived_Base);
16006 while Present (D) loop
16007 Append_Elmt (New_Reference_To (D, Loc), Discs);
16008 Next_Discriminant (D);
16012 -- Finally, inherit non-discriminant components unless they are not
16013 -- visible because defined or inherited from the full view of the
16014 -- parent. Don't inherit the _parent field of the parent type.
16016 Component := First_Entity (Parent_Base);
16017 while Present (Component) loop
16019 -- Ada 2005 (AI-251): Do not inherit components associated with
16020 -- secondary tags of the parent.
16022 if Ekind (Component) = E_Component
16023 and then Present (Related_Type (Component))
16027 elsif Ekind (Component) /= E_Component
16028 or else Chars (Component) = Name_uParent
16032 -- If the derived type is within the parent type's declarative
16033 -- region, then the components can still be inherited even though
16034 -- they aren't visible at this point. This can occur for cases
16035 -- such as within public child units where the components must
16036 -- become visible upon entering the child unit's private part.
16038 elsif not Is_Visible_Component (Component)
16039 and then not In_Open_Scopes (Scope (Parent_Base))
16043 elsif Ekind_In (Derived_Base, E_Private_Type,
16044 E_Limited_Private_Type)
16049 Inherit_Component (Component);
16052 Next_Entity (Component);
16055 -- For tagged derived types, inherited discriminants cannot be used in
16056 -- component declarations of the record extension part. To achieve this
16057 -- we mark the inherited discriminants as not visible.
16059 if Is_Tagged and then Inherit_Discr then
16060 D := First_Discriminant (Derived_Base);
16061 while Present (D) loop
16062 Set_Is_Immediately_Visible (D, False);
16063 Next_Discriminant (D);
16068 end Inherit_Components;
16070 -----------------------
16071 -- Is_Constant_Bound --
16072 -----------------------
16074 function Is_Constant_Bound (Exp : Node_Id) return Boolean is
16076 if Compile_Time_Known_Value (Exp) then
16079 elsif Is_Entity_Name (Exp)
16080 and then Present (Entity (Exp))
16082 return Is_Constant_Object (Entity (Exp))
16083 or else Ekind (Entity (Exp)) = E_Enumeration_Literal;
16085 elsif Nkind (Exp) in N_Binary_Op then
16086 return Is_Constant_Bound (Left_Opnd (Exp))
16087 and then Is_Constant_Bound (Right_Opnd (Exp))
16088 and then Scope (Entity (Exp)) = Standard_Standard;
16093 end Is_Constant_Bound;
16095 -----------------------
16096 -- Is_Null_Extension --
16097 -----------------------
16099 function Is_Null_Extension (T : Entity_Id) return Boolean is
16100 Type_Decl : constant Node_Id := Parent (Base_Type (T));
16101 Comp_List : Node_Id;
16105 if Nkind (Type_Decl) /= N_Full_Type_Declaration
16106 or else not Is_Tagged_Type (T)
16107 or else Nkind (Type_Definition (Type_Decl)) /=
16108 N_Derived_Type_Definition
16109 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
16115 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
16117 if Present (Discriminant_Specifications (Type_Decl)) then
16120 elsif Present (Comp_List)
16121 and then Is_Non_Empty_List (Component_Items (Comp_List))
16123 Comp := First (Component_Items (Comp_List));
16125 -- Only user-defined components are relevant. The component list
16126 -- may also contain a parent component and internal components
16127 -- corresponding to secondary tags, but these do not determine
16128 -- whether this is a null extension.
16130 while Present (Comp) loop
16131 if Comes_From_Source (Comp) then
16142 end Is_Null_Extension;
16144 ------------------------------
16145 -- Is_Valid_Constraint_Kind --
16146 ------------------------------
16148 function Is_Valid_Constraint_Kind
16149 (T_Kind : Type_Kind;
16150 Constraint_Kind : Node_Kind) return Boolean
16154 when Enumeration_Kind |
16156 return Constraint_Kind = N_Range_Constraint;
16158 when Decimal_Fixed_Point_Kind =>
16159 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
16160 N_Range_Constraint);
16162 when Ordinary_Fixed_Point_Kind =>
16163 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
16164 N_Range_Constraint);
16167 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
16168 N_Range_Constraint);
16175 E_Incomplete_Type |
16178 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
16181 return True; -- Error will be detected later
16183 end Is_Valid_Constraint_Kind;
16185 --------------------------
16186 -- Is_Visible_Component --
16187 --------------------------
16189 function Is_Visible_Component (C : Entity_Id) return Boolean is
16190 Original_Comp : Entity_Id := Empty;
16191 Original_Scope : Entity_Id;
16192 Type_Scope : Entity_Id;
16194 function Is_Local_Type (Typ : Entity_Id) return Boolean;
16195 -- Check whether parent type of inherited component is declared locally,
16196 -- possibly within a nested package or instance. The current scope is
16197 -- the derived record itself.
16199 -------------------
16200 -- Is_Local_Type --
16201 -------------------
16203 function Is_Local_Type (Typ : Entity_Id) return Boolean is
16207 Scop := Scope (Typ);
16208 while Present (Scop)
16209 and then Scop /= Standard_Standard
16211 if Scop = Scope (Current_Scope) then
16215 Scop := Scope (Scop);
16221 -- Start of processing for Is_Visible_Component
16224 if Ekind_In (C, E_Component, E_Discriminant) then
16225 Original_Comp := Original_Record_Component (C);
16228 if No (Original_Comp) then
16230 -- Premature usage, or previous error
16235 Original_Scope := Scope (Original_Comp);
16236 Type_Scope := Scope (Base_Type (Scope (C)));
16239 -- This test only concerns tagged types
16241 if not Is_Tagged_Type (Original_Scope) then
16244 -- If it is _Parent or _Tag, there is no visibility issue
16246 elsif not Comes_From_Source (Original_Comp) then
16249 -- Discriminants are always visible
16251 elsif Ekind (Original_Comp) = E_Discriminant
16252 and then not Has_Unknown_Discriminants (Original_Scope)
16256 -- If we are in the body of an instantiation, the component is visible
16257 -- if the parent type is non-private, or in an enclosing scope. The
16258 -- scope stack is not present when analyzing an instance body, so we
16259 -- must inspect the chain of scopes explicitly.
16261 elsif In_Instance_Body then
16262 if not Is_Private_Type (Scope (C)) then
16270 S := Current_Scope;
16272 and then S /= Standard_Standard
16274 if S = Type_Scope then
16285 -- If the component has been declared in an ancestor which is currently
16286 -- a private type, then it is not visible. The same applies if the
16287 -- component's containing type is not in an open scope and the original
16288 -- component's enclosing type is a visible full view of a private type
16289 -- (which can occur in cases where an attempt is being made to reference
16290 -- a component in a sibling package that is inherited from a visible
16291 -- component of a type in an ancestor package; the component in the
16292 -- sibling package should not be visible even though the component it
16293 -- inherited from is visible). This does not apply however in the case
16294 -- where the scope of the type is a private child unit, or when the
16295 -- parent comes from a local package in which the ancestor is currently
16296 -- visible. The latter suppression of visibility is needed for cases
16297 -- that are tested in B730006.
16299 elsif Is_Private_Type (Original_Scope)
16301 (not Is_Private_Descendant (Type_Scope)
16302 and then not In_Open_Scopes (Type_Scope)
16303 and then Has_Private_Declaration (Original_Scope))
16305 -- If the type derives from an entity in a formal package, there
16306 -- are no additional visible components.
16308 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
16309 N_Formal_Package_Declaration
16313 -- if we are not in the private part of the current package, there
16314 -- are no additional visible components.
16316 elsif Ekind (Scope (Current_Scope)) = E_Package
16317 and then not In_Private_Part (Scope (Current_Scope))
16322 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
16323 and then In_Open_Scopes (Scope (Original_Scope))
16324 and then Is_Local_Type (Type_Scope);
16327 -- There is another weird way in which a component may be invisible
16328 -- when the private and the full view are not derived from the same
16329 -- ancestor. Here is an example :
16331 -- type A1 is tagged record F1 : integer; end record;
16332 -- type A2 is new A1 with record F2 : integer; end record;
16333 -- type T is new A1 with private;
16335 -- type T is new A2 with null record;
16337 -- In this case, the full view of T inherits F1 and F2 but the private
16338 -- view inherits only F1
16342 Ancestor : Entity_Id := Scope (C);
16346 if Ancestor = Original_Scope then
16348 elsif Ancestor = Etype (Ancestor) then
16352 Ancestor := Etype (Ancestor);
16356 end Is_Visible_Component;
16358 --------------------------
16359 -- Make_Class_Wide_Type --
16360 --------------------------
16362 procedure Make_Class_Wide_Type (T : Entity_Id) is
16363 CW_Type : Entity_Id;
16365 Next_E : Entity_Id;
16368 if Present (Class_Wide_Type (T)) then
16370 -- The class-wide type is a partially decorated entity created for a
16371 -- unanalyzed tagged type referenced through a limited with clause.
16372 -- When the tagged type is analyzed, its class-wide type needs to be
16373 -- redecorated. Note that we reuse the entity created by Decorate_
16374 -- Tagged_Type in order to preserve all links.
16376 if Materialize_Entity (Class_Wide_Type (T)) then
16377 CW_Type := Class_Wide_Type (T);
16378 Set_Materialize_Entity (CW_Type, False);
16380 -- The class wide type can have been defined by the partial view, in
16381 -- which case everything is already done.
16387 -- Default case, we need to create a new class-wide type
16391 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
16394 -- Inherit root type characteristics
16396 CW_Name := Chars (CW_Type);
16397 Next_E := Next_Entity (CW_Type);
16398 Copy_Node (T, CW_Type);
16399 Set_Comes_From_Source (CW_Type, False);
16400 Set_Chars (CW_Type, CW_Name);
16401 Set_Parent (CW_Type, Parent (T));
16402 Set_Next_Entity (CW_Type, Next_E);
16404 -- Ensure we have a new freeze node for the class-wide type. The partial
16405 -- view may have freeze action of its own, requiring a proper freeze
16406 -- node, and the same freeze node cannot be shared between the two
16409 Set_Has_Delayed_Freeze (CW_Type);
16410 Set_Freeze_Node (CW_Type, Empty);
16412 -- Customize the class-wide type: It has no prim. op., it cannot be
16413 -- abstract and its Etype points back to the specific root type.
16415 Set_Ekind (CW_Type, E_Class_Wide_Type);
16416 Set_Is_Tagged_Type (CW_Type, True);
16417 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
16418 Set_Is_Abstract_Type (CW_Type, False);
16419 Set_Is_Constrained (CW_Type, False);
16420 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
16422 if Ekind (T) = E_Class_Wide_Subtype then
16423 Set_Etype (CW_Type, Etype (Base_Type (T)));
16425 Set_Etype (CW_Type, T);
16428 -- If this is the class_wide type of a constrained subtype, it does
16429 -- not have discriminants.
16431 Set_Has_Discriminants (CW_Type,
16432 Has_Discriminants (T) and then not Is_Constrained (T));
16434 Set_Has_Unknown_Discriminants (CW_Type, True);
16435 Set_Class_Wide_Type (T, CW_Type);
16436 Set_Equivalent_Type (CW_Type, Empty);
16438 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
16440 Set_Class_Wide_Type (CW_Type, CW_Type);
16441 end Make_Class_Wide_Type;
16447 procedure Make_Index
16449 Related_Nod : Node_Id;
16450 Related_Id : Entity_Id := Empty;
16451 Suffix_Index : Nat := 1;
16452 In_Iter_Schm : Boolean := False)
16456 Def_Id : Entity_Id := Empty;
16457 Found : Boolean := False;
16460 -- For a discrete range used in a constrained array definition and
16461 -- defined by a range, an implicit conversion to the predefined type
16462 -- INTEGER is assumed if each bound is either a numeric literal, a named
16463 -- number, or an attribute, and the type of both bounds (prior to the
16464 -- implicit conversion) is the type universal_integer. Otherwise, both
16465 -- bounds must be of the same discrete type, other than universal
16466 -- integer; this type must be determinable independently of the
16467 -- context, but using the fact that the type must be discrete and that
16468 -- both bounds must have the same type.
16470 -- Character literals also have a universal type in the absence of
16471 -- of additional context, and are resolved to Standard_Character.
16473 if Nkind (I) = N_Range then
16475 -- The index is given by a range constraint. The bounds are known
16476 -- to be of a consistent type.
16478 if not Is_Overloaded (I) then
16481 -- For universal bounds, choose the specific predefined type
16483 if T = Universal_Integer then
16484 T := Standard_Integer;
16486 elsif T = Any_Character then
16487 Ambiguous_Character (Low_Bound (I));
16489 T := Standard_Character;
16492 -- The node may be overloaded because some user-defined operators
16493 -- are available, but if a universal interpretation exists it is
16494 -- also the selected one.
16496 elsif Universal_Interpretation (I) = Universal_Integer then
16497 T := Standard_Integer;
16503 Ind : Interp_Index;
16507 Get_First_Interp (I, Ind, It);
16508 while Present (It.Typ) loop
16509 if Is_Discrete_Type (It.Typ) then
16512 and then not Covers (It.Typ, T)
16513 and then not Covers (T, It.Typ)
16515 Error_Msg_N ("ambiguous bounds in discrete range", I);
16523 Get_Next_Interp (Ind, It);
16526 if T = Any_Type then
16527 Error_Msg_N ("discrete type required for range", I);
16528 Set_Etype (I, Any_Type);
16531 elsif T = Universal_Integer then
16532 T := Standard_Integer;
16537 if not Is_Discrete_Type (T) then
16538 Error_Msg_N ("discrete type required for range", I);
16539 Set_Etype (I, Any_Type);
16543 if Nkind (Low_Bound (I)) = N_Attribute_Reference
16544 and then Attribute_Name (Low_Bound (I)) = Name_First
16545 and then Is_Entity_Name (Prefix (Low_Bound (I)))
16546 and then Is_Type (Entity (Prefix (Low_Bound (I))))
16547 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (I))))
16549 -- The type of the index will be the type of the prefix, as long
16550 -- as the upper bound is 'Last of the same type.
16552 Def_Id := Entity (Prefix (Low_Bound (I)));
16554 if Nkind (High_Bound (I)) /= N_Attribute_Reference
16555 or else Attribute_Name (High_Bound (I)) /= Name_Last
16556 or else not Is_Entity_Name (Prefix (High_Bound (I)))
16557 or else Entity (Prefix (High_Bound (I))) /= Def_Id
16564 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
16566 elsif Nkind (I) = N_Subtype_Indication then
16568 -- The index is given by a subtype with a range constraint
16570 T := Base_Type (Entity (Subtype_Mark (I)));
16572 if not Is_Discrete_Type (T) then
16573 Error_Msg_N ("discrete type required for range", I);
16574 Set_Etype (I, Any_Type);
16578 R := Range_Expression (Constraint (I));
16581 Process_Range_Expr_In_Decl
16582 (R, Entity (Subtype_Mark (I)), In_Iter_Schm => In_Iter_Schm);
16584 elsif Nkind (I) = N_Attribute_Reference then
16586 -- The parser guarantees that the attribute is a RANGE attribute
16588 -- If the node denotes the range of a type mark, that is also the
16589 -- resulting type, and we do no need to create an Itype for it.
16591 if Is_Entity_Name (Prefix (I))
16592 and then Comes_From_Source (I)
16593 and then Is_Type (Entity (Prefix (I)))
16594 and then Is_Discrete_Type (Entity (Prefix (I)))
16596 Def_Id := Entity (Prefix (I));
16599 Analyze_And_Resolve (I);
16603 -- If none of the above, must be a subtype. We convert this to a
16604 -- range attribute reference because in the case of declared first
16605 -- named subtypes, the types in the range reference can be different
16606 -- from the type of the entity. A range attribute normalizes the
16607 -- reference and obtains the correct types for the bounds.
16609 -- This transformation is in the nature of an expansion, is only
16610 -- done if expansion is active. In particular, it is not done on
16611 -- formal generic types, because we need to retain the name of the
16612 -- original index for instantiation purposes.
16615 if not Is_Entity_Name (I) or else not Is_Type (Entity (I)) then
16616 Error_Msg_N ("invalid subtype mark in discrete range ", I);
16617 Set_Etype (I, Any_Integer);
16621 -- The type mark may be that of an incomplete type. It is only
16622 -- now that we can get the full view, previous analysis does
16623 -- not look specifically for a type mark.
16625 Set_Entity (I, Get_Full_View (Entity (I)));
16626 Set_Etype (I, Entity (I));
16627 Def_Id := Entity (I);
16629 if not Is_Discrete_Type (Def_Id) then
16630 Error_Msg_N ("discrete type required for index", I);
16631 Set_Etype (I, Any_Type);
16636 if Expander_Active then
16638 Make_Attribute_Reference (Sloc (I),
16639 Attribute_Name => Name_Range,
16640 Prefix => Relocate_Node (I)));
16642 -- The original was a subtype mark that does not freeze. This
16643 -- means that the rewritten version must not freeze either.
16645 Set_Must_Not_Freeze (I);
16646 Set_Must_Not_Freeze (Prefix (I));
16648 -- Is order critical??? if so, document why, if not
16649 -- use Analyze_And_Resolve
16651 Analyze_And_Resolve (I);
16655 -- If expander is inactive, type is legal, nothing else to construct
16662 if not Is_Discrete_Type (T) then
16663 Error_Msg_N ("discrete type required for range", I);
16664 Set_Etype (I, Any_Type);
16667 elsif T = Any_Type then
16668 Set_Etype (I, Any_Type);
16672 -- We will now create the appropriate Itype to describe the range, but
16673 -- first a check. If we originally had a subtype, then we just label
16674 -- the range with this subtype. Not only is there no need to construct
16675 -- a new subtype, but it is wrong to do so for two reasons:
16677 -- 1. A legality concern, if we have a subtype, it must not freeze,
16678 -- and the Itype would cause freezing incorrectly
16680 -- 2. An efficiency concern, if we created an Itype, it would not be
16681 -- recognized as the same type for the purposes of eliminating
16682 -- checks in some circumstances.
16684 -- We signal this case by setting the subtype entity in Def_Id
16686 if No (Def_Id) then
16688 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
16689 Set_Etype (Def_Id, Base_Type (T));
16691 if Is_Signed_Integer_Type (T) then
16692 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
16694 elsif Is_Modular_Integer_Type (T) then
16695 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
16698 Set_Ekind (Def_Id, E_Enumeration_Subtype);
16699 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
16700 Set_First_Literal (Def_Id, First_Literal (T));
16703 Set_Size_Info (Def_Id, (T));
16704 Set_RM_Size (Def_Id, RM_Size (T));
16705 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
16707 Set_Scalar_Range (Def_Id, R);
16708 Conditional_Delay (Def_Id, T);
16710 -- In the subtype indication case, if the immediate parent of the
16711 -- new subtype is non-static, then the subtype we create is non-
16712 -- static, even if its bounds are static.
16714 if Nkind (I) = N_Subtype_Indication
16715 and then not Is_Static_Subtype (Entity (Subtype_Mark (I)))
16717 Set_Is_Non_Static_Subtype (Def_Id);
16721 -- Final step is to label the index with this constructed type
16723 Set_Etype (I, Def_Id);
16726 ------------------------------
16727 -- Modular_Type_Declaration --
16728 ------------------------------
16730 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16731 Mod_Expr : constant Node_Id := Expression (Def);
16734 procedure Set_Modular_Size (Bits : Int);
16735 -- Sets RM_Size to Bits, and Esize to normal word size above this
16737 ----------------------
16738 -- Set_Modular_Size --
16739 ----------------------
16741 procedure Set_Modular_Size (Bits : Int) is
16743 Set_RM_Size (T, UI_From_Int (Bits));
16748 elsif Bits <= 16 then
16749 Init_Esize (T, 16);
16751 elsif Bits <= 32 then
16752 Init_Esize (T, 32);
16755 Init_Esize (T, System_Max_Binary_Modulus_Power);
16758 if not Non_Binary_Modulus (T)
16759 and then Esize (T) = RM_Size (T)
16761 Set_Is_Known_Valid (T);
16763 end Set_Modular_Size;
16765 -- Start of processing for Modular_Type_Declaration
16768 Analyze_And_Resolve (Mod_Expr, Any_Integer);
16770 Set_Ekind (T, E_Modular_Integer_Type);
16771 Init_Alignment (T);
16772 Set_Is_Constrained (T);
16774 if not Is_OK_Static_Expression (Mod_Expr) then
16775 Flag_Non_Static_Expr
16776 ("non-static expression used for modular type bound!", Mod_Expr);
16777 M_Val := 2 ** System_Max_Binary_Modulus_Power;
16779 M_Val := Expr_Value (Mod_Expr);
16783 Error_Msg_N ("modulus value must be positive", Mod_Expr);
16784 M_Val := 2 ** System_Max_Binary_Modulus_Power;
16787 Set_Modulus (T, M_Val);
16789 -- Create bounds for the modular type based on the modulus given in
16790 -- the type declaration and then analyze and resolve those bounds.
16792 Set_Scalar_Range (T,
16793 Make_Range (Sloc (Mod_Expr),
16794 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
16795 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
16797 -- Properly analyze the literals for the range. We do this manually
16798 -- because we can't go calling Resolve, since we are resolving these
16799 -- bounds with the type, and this type is certainly not complete yet!
16801 Set_Etype (Low_Bound (Scalar_Range (T)), T);
16802 Set_Etype (High_Bound (Scalar_Range (T)), T);
16803 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
16804 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
16806 -- Loop through powers of two to find number of bits required
16808 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
16812 if M_Val = 2 ** Bits then
16813 Set_Modular_Size (Bits);
16818 elsif M_Val < 2 ** Bits then
16819 Check_SPARK_Restriction ("modulus should be a power of 2", T);
16820 Set_Non_Binary_Modulus (T);
16822 if Bits > System_Max_Nonbinary_Modulus_Power then
16823 Error_Msg_Uint_1 :=
16824 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
16826 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
16827 Set_Modular_Size (System_Max_Binary_Modulus_Power);
16831 -- In the non-binary case, set size as per RM 13.3(55)
16833 Set_Modular_Size (Bits);
16840 -- If we fall through, then the size exceed System.Max_Binary_Modulus
16841 -- so we just signal an error and set the maximum size.
16843 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
16844 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
16846 Set_Modular_Size (System_Max_Binary_Modulus_Power);
16847 Init_Alignment (T);
16849 end Modular_Type_Declaration;
16851 --------------------------
16852 -- New_Concatenation_Op --
16853 --------------------------
16855 procedure New_Concatenation_Op (Typ : Entity_Id) is
16856 Loc : constant Source_Ptr := Sloc (Typ);
16859 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
16860 -- Create abbreviated declaration for the formal of a predefined
16861 -- Operator 'Op' of type 'Typ'
16863 --------------------
16864 -- Make_Op_Formal --
16865 --------------------
16867 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
16868 Formal : Entity_Id;
16870 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
16871 Set_Etype (Formal, Typ);
16872 Set_Mechanism (Formal, Default_Mechanism);
16874 end Make_Op_Formal;
16876 -- Start of processing for New_Concatenation_Op
16879 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
16881 Set_Ekind (Op, E_Operator);
16882 Set_Scope (Op, Current_Scope);
16883 Set_Etype (Op, Typ);
16884 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
16885 Set_Is_Immediately_Visible (Op);
16886 Set_Is_Intrinsic_Subprogram (Op);
16887 Set_Has_Completion (Op);
16888 Append_Entity (Op, Current_Scope);
16890 Set_Name_Entity_Id (Name_Op_Concat, Op);
16892 Append_Entity (Make_Op_Formal (Typ, Op), Op);
16893 Append_Entity (Make_Op_Formal (Typ, Op), Op);
16894 end New_Concatenation_Op;
16896 -------------------------
16897 -- OK_For_Limited_Init --
16898 -------------------------
16900 -- ???Check all calls of this, and compare the conditions under which it's
16903 function OK_For_Limited_Init
16905 Exp : Node_Id) return Boolean
16908 return Is_CPP_Constructor_Call (Exp)
16909 or else (Ada_Version >= Ada_2005
16910 and then not Debug_Flag_Dot_L
16911 and then OK_For_Limited_Init_In_05 (Typ, Exp));
16912 end OK_For_Limited_Init;
16914 -------------------------------
16915 -- OK_For_Limited_Init_In_05 --
16916 -------------------------------
16918 function OK_For_Limited_Init_In_05
16920 Exp : Node_Id) return Boolean
16923 -- An object of a limited interface type can be initialized with any
16924 -- expression of a nonlimited descendant type.
16926 if Is_Class_Wide_Type (Typ)
16927 and then Is_Limited_Interface (Typ)
16928 and then not Is_Limited_Type (Etype (Exp))
16933 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
16934 -- case of limited aggregates (including extension aggregates), and
16935 -- function calls. The function call may have been given in prefixed
16936 -- notation, in which case the original node is an indexed component.
16937 -- If the function is parameterless, the original node was an explicit
16938 -- dereference. The function may also be parameterless, in which case
16939 -- the source node is just an identifier.
16941 case Nkind (Original_Node (Exp)) is
16942 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
16945 when N_Identifier =>
16946 return Present (Entity (Original_Node (Exp)))
16947 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
16949 when N_Qualified_Expression =>
16951 OK_For_Limited_Init_In_05
16952 (Typ, Expression (Original_Node (Exp)));
16954 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
16955 -- with a function call, the expander has rewritten the call into an
16956 -- N_Type_Conversion node to force displacement of the pointer to
16957 -- reference the component containing the secondary dispatch table.
16958 -- Otherwise a type conversion is not a legal context.
16959 -- A return statement for a build-in-place function returning a
16960 -- synchronized type also introduces an unchecked conversion.
16962 when N_Type_Conversion |
16963 N_Unchecked_Type_Conversion =>
16964 return not Comes_From_Source (Exp)
16966 OK_For_Limited_Init_In_05
16967 (Typ, Expression (Original_Node (Exp)));
16969 when N_Indexed_Component |
16970 N_Selected_Component |
16971 N_Explicit_Dereference =>
16972 return Nkind (Exp) = N_Function_Call;
16974 -- A use of 'Input is a function call, hence allowed. Normally the
16975 -- attribute will be changed to a call, but the attribute by itself
16976 -- can occur with -gnatc.
16978 when N_Attribute_Reference =>
16979 return Attribute_Name (Original_Node (Exp)) = Name_Input;
16981 -- For a conditional expression, all dependent expressions must be
16982 -- legal constructs.
16984 when N_Conditional_Expression =>
16986 Then_Expr : constant Node_Id :=
16987 Next (First (Expressions (Original_Node (Exp))));
16988 Else_Expr : constant Node_Id := Next (Then_Expr);
16990 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
16991 and then OK_For_Limited_Init_In_05 (Typ, Else_Expr);
16994 when N_Case_Expression =>
16999 Alt := First (Alternatives (Original_Node (Exp)));
17000 while Present (Alt) loop
17001 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
17014 end OK_For_Limited_Init_In_05;
17016 -------------------------------------------
17017 -- Ordinary_Fixed_Point_Type_Declaration --
17018 -------------------------------------------
17020 procedure Ordinary_Fixed_Point_Type_Declaration
17024 Loc : constant Source_Ptr := Sloc (Def);
17025 Delta_Expr : constant Node_Id := Delta_Expression (Def);
17026 RRS : constant Node_Id := Real_Range_Specification (Def);
17027 Implicit_Base : Entity_Id;
17034 Check_Restriction (No_Fixed_Point, Def);
17036 -- Create implicit base type
17039 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
17040 Set_Etype (Implicit_Base, Implicit_Base);
17042 -- Analyze and process delta expression
17044 Analyze_And_Resolve (Delta_Expr, Any_Real);
17046 Check_Delta_Expression (Delta_Expr);
17047 Delta_Val := Expr_Value_R (Delta_Expr);
17049 Set_Delta_Value (Implicit_Base, Delta_Val);
17051 -- Compute default small from given delta, which is the largest power
17052 -- of two that does not exceed the given delta value.
17062 if Delta_Val < Ureal_1 then
17063 while Delta_Val < Tmp loop
17064 Tmp := Tmp / Ureal_2;
17065 Scale := Scale + 1;
17070 Tmp := Tmp * Ureal_2;
17071 exit when Tmp > Delta_Val;
17072 Scale := Scale - 1;
17076 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
17079 Set_Small_Value (Implicit_Base, Small_Val);
17081 -- If no range was given, set a dummy range
17083 if RRS <= Empty_Or_Error then
17084 Low_Val := -Small_Val;
17085 High_Val := Small_Val;
17087 -- Otherwise analyze and process given range
17091 Low : constant Node_Id := Low_Bound (RRS);
17092 High : constant Node_Id := High_Bound (RRS);
17095 Analyze_And_Resolve (Low, Any_Real);
17096 Analyze_And_Resolve (High, Any_Real);
17097 Check_Real_Bound (Low);
17098 Check_Real_Bound (High);
17100 -- Obtain and set the range
17102 Low_Val := Expr_Value_R (Low);
17103 High_Val := Expr_Value_R (High);
17105 if Low_Val > High_Val then
17106 Error_Msg_NE ("?fixed point type& has null range", Def, T);
17111 -- The range for both the implicit base and the declared first subtype
17112 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
17113 -- set a temporary range in place. Note that the bounds of the base
17114 -- type will be widened to be symmetrical and to fill the available
17115 -- bits when the type is frozen.
17117 -- We could do this with all discrete types, and probably should, but
17118 -- we absolutely have to do it for fixed-point, since the end-points
17119 -- of the range and the size are determined by the small value, which
17120 -- could be reset before the freeze point.
17122 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
17123 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
17125 -- Complete definition of first subtype
17127 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
17128 Set_Etype (T, Implicit_Base);
17129 Init_Size_Align (T);
17130 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
17131 Set_Small_Value (T, Small_Val);
17132 Set_Delta_Value (T, Delta_Val);
17133 Set_Is_Constrained (T);
17135 end Ordinary_Fixed_Point_Type_Declaration;
17137 ----------------------------------------
17138 -- Prepare_Private_Subtype_Completion --
17139 ----------------------------------------
17141 procedure Prepare_Private_Subtype_Completion
17143 Related_Nod : Node_Id)
17145 Id_B : constant Entity_Id := Base_Type (Id);
17146 Full_B : constant Entity_Id := Full_View (Id_B);
17150 if Present (Full_B) then
17152 -- The Base_Type is already completed, we can complete the subtype
17153 -- now. We have to create a new entity with the same name, Thus we
17154 -- can't use Create_Itype.
17156 -- This is messy, should be fixed ???
17158 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
17159 Set_Is_Itype (Full);
17160 Set_Associated_Node_For_Itype (Full, Related_Nod);
17161 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
17164 -- The parent subtype may be private, but the base might not, in some
17165 -- nested instances. In that case, the subtype does not need to be
17166 -- exchanged. It would still be nice to make private subtypes and their
17167 -- bases consistent at all times ???
17169 if Is_Private_Type (Id_B) then
17170 Append_Elmt (Id, Private_Dependents (Id_B));
17173 end Prepare_Private_Subtype_Completion;
17175 ---------------------------
17176 -- Process_Discriminants --
17177 ---------------------------
17179 procedure Process_Discriminants
17181 Prev : Entity_Id := Empty)
17183 Elist : constant Elist_Id := New_Elmt_List;
17186 Discr_Number : Uint;
17187 Discr_Type : Entity_Id;
17188 Default_Present : Boolean := False;
17189 Default_Not_Present : Boolean := False;
17192 -- A composite type other than an array type can have discriminants.
17193 -- On entry, the current scope is the composite type.
17195 -- The discriminants are initially entered into the scope of the type
17196 -- via Enter_Name with the default Ekind of E_Void to prevent premature
17197 -- use, as explained at the end of this procedure.
17199 Discr := First (Discriminant_Specifications (N));
17200 while Present (Discr) loop
17201 Enter_Name (Defining_Identifier (Discr));
17203 -- For navigation purposes we add a reference to the discriminant
17204 -- in the entity for the type. If the current declaration is a
17205 -- completion, place references on the partial view. Otherwise the
17206 -- type is the current scope.
17208 if Present (Prev) then
17210 -- The references go on the partial view, if present. If the
17211 -- partial view has discriminants, the references have been
17212 -- generated already.
17214 if not Has_Discriminants (Prev) then
17215 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
17219 (Current_Scope, Defining_Identifier (Discr), 'd');
17222 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
17223 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
17225 -- Ada 2005 (AI-254)
17227 if Present (Access_To_Subprogram_Definition
17228 (Discriminant_Type (Discr)))
17229 and then Protected_Present (Access_To_Subprogram_Definition
17230 (Discriminant_Type (Discr)))
17233 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
17237 Find_Type (Discriminant_Type (Discr));
17238 Discr_Type := Etype (Discriminant_Type (Discr));
17240 if Error_Posted (Discriminant_Type (Discr)) then
17241 Discr_Type := Any_Type;
17245 if Is_Access_Type (Discr_Type) then
17247 -- Ada 2005 (AI-230): Access discriminant allowed in non-limited
17250 if Ada_Version < Ada_2005 then
17251 Check_Access_Discriminant_Requires_Limited
17252 (Discr, Discriminant_Type (Discr));
17255 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
17257 ("(Ada 83) access discriminant not allowed", Discr);
17260 elsif not Is_Discrete_Type (Discr_Type) then
17261 Error_Msg_N ("discriminants must have a discrete or access type",
17262 Discriminant_Type (Discr));
17265 Set_Etype (Defining_Identifier (Discr), Discr_Type);
17267 -- If a discriminant specification includes the assignment compound
17268 -- delimiter followed by an expression, the expression is the default
17269 -- expression of the discriminant; the default expression must be of
17270 -- the type of the discriminant. (RM 3.7.1) Since this expression is
17271 -- a default expression, we do the special preanalysis, since this
17272 -- expression does not freeze (see "Handling of Default and Per-
17273 -- Object Expressions" in spec of package Sem).
17275 if Present (Expression (Discr)) then
17276 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
17278 if Nkind (N) = N_Formal_Type_Declaration then
17280 ("discriminant defaults not allowed for formal type",
17281 Expression (Discr));
17283 -- Flag an error for a tagged type with defaulted discriminants,
17284 -- excluding limited tagged types when compiling for Ada 2012
17285 -- (see AI05-0214).
17287 elsif Is_Tagged_Type (Current_Scope)
17288 and then (not Is_Limited_Type (Current_Scope)
17289 or else Ada_Version < Ada_2012)
17290 and then Comes_From_Source (N)
17292 -- Note: see similar test in Check_Or_Process_Discriminants, to
17293 -- handle the (illegal) case of the completion of an untagged
17294 -- view with discriminants with defaults by a tagged full view.
17295 -- We skip the check if Discr does not come from source, to
17296 -- account for the case of an untagged derived type providing
17297 -- defaults for a renamed discriminant from a private untagged
17298 -- ancestor with a tagged full view (ACATS B460006).
17300 if Ada_Version >= Ada_2012 then
17302 ("discriminants of nonlimited tagged type cannot have"
17304 Expression (Discr));
17307 ("discriminants of tagged type cannot have defaults",
17308 Expression (Discr));
17312 Default_Present := True;
17313 Append_Elmt (Expression (Discr), Elist);
17315 -- Tag the defining identifiers for the discriminants with
17316 -- their corresponding default expressions from the tree.
17318 Set_Discriminant_Default_Value
17319 (Defining_Identifier (Discr), Expression (Discr));
17323 Default_Not_Present := True;
17326 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
17327 -- Discr_Type but with the null-exclusion attribute
17329 if Ada_Version >= Ada_2005 then
17331 -- Ada 2005 (AI-231): Static checks
17333 if Can_Never_Be_Null (Discr_Type) then
17334 Null_Exclusion_Static_Checks (Discr);
17336 elsif Is_Access_Type (Discr_Type)
17337 and then Null_Exclusion_Present (Discr)
17339 -- No need to check itypes because in their case this check
17340 -- was done at their point of creation
17342 and then not Is_Itype (Discr_Type)
17344 if Can_Never_Be_Null (Discr_Type) then
17346 ("`NOT NULL` not allowed (& already excludes null)",
17351 Set_Etype (Defining_Identifier (Discr),
17352 Create_Null_Excluding_Itype
17354 Related_Nod => Discr));
17356 -- Check for improper null exclusion if the type is otherwise
17357 -- legal for a discriminant.
17359 elsif Null_Exclusion_Present (Discr)
17360 and then Is_Discrete_Type (Discr_Type)
17363 ("null exclusion can only apply to an access type", Discr);
17366 -- Ada 2005 (AI-402): access discriminants of nonlimited types
17367 -- can't have defaults. Synchronized types, or types that are
17368 -- explicitly limited are fine, but special tests apply to derived
17369 -- types in generics: in a generic body we have to assume the
17370 -- worst, and therefore defaults are not allowed if the parent is
17371 -- a generic formal private type (see ACATS B370001).
17373 if Is_Access_Type (Discr_Type) and then Default_Present then
17374 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
17375 or else Is_Limited_Record (Current_Scope)
17376 or else Is_Concurrent_Type (Current_Scope)
17377 or else Is_Concurrent_Record_Type (Current_Scope)
17378 or else Ekind (Current_Scope) = E_Limited_Private_Type
17380 if not Is_Derived_Type (Current_Scope)
17381 or else not Is_Generic_Type (Etype (Current_Scope))
17382 or else not In_Package_Body (Scope (Etype (Current_Scope)))
17383 or else Limited_Present
17384 (Type_Definition (Parent (Current_Scope)))
17389 Error_Msg_N ("access discriminants of nonlimited types",
17390 Expression (Discr));
17391 Error_Msg_N ("\cannot have defaults", Expression (Discr));
17394 elsif Present (Expression (Discr)) then
17396 ("(Ada 2005) access discriminants of nonlimited types",
17397 Expression (Discr));
17398 Error_Msg_N ("\cannot have defaults", Expression (Discr));
17406 -- An element list consisting of the default expressions of the
17407 -- discriminants is constructed in the above loop and used to set
17408 -- the Discriminant_Constraint attribute for the type. If an object
17409 -- is declared of this (record or task) type without any explicit
17410 -- discriminant constraint given, this element list will form the
17411 -- actual parameters for the corresponding initialization procedure
17414 Set_Discriminant_Constraint (Current_Scope, Elist);
17415 Set_Stored_Constraint (Current_Scope, No_Elist);
17417 -- Default expressions must be provided either for all or for none
17418 -- of the discriminants of a discriminant part. (RM 3.7.1)
17420 if Default_Present and then Default_Not_Present then
17422 ("incomplete specification of defaults for discriminants", N);
17425 -- The use of the name of a discriminant is not allowed in default
17426 -- expressions of a discriminant part if the specification of the
17427 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
17429 -- To detect this, the discriminant names are entered initially with an
17430 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
17431 -- attempt to use a void entity (for example in an expression that is
17432 -- type-checked) produces the error message: premature usage. Now after
17433 -- completing the semantic analysis of the discriminant part, we can set
17434 -- the Ekind of all the discriminants appropriately.
17436 Discr := First (Discriminant_Specifications (N));
17437 Discr_Number := Uint_1;
17438 while Present (Discr) loop
17439 Id := Defining_Identifier (Discr);
17440 Set_Ekind (Id, E_Discriminant);
17441 Init_Component_Location (Id);
17443 Set_Discriminant_Number (Id, Discr_Number);
17445 -- Make sure this is always set, even in illegal programs
17447 Set_Corresponding_Discriminant (Id, Empty);
17449 -- Initialize the Original_Record_Component to the entity itself.
17450 -- Inherit_Components will propagate the right value to
17451 -- discriminants in derived record types.
17453 Set_Original_Record_Component (Id, Id);
17455 -- Create the discriminal for the discriminant
17457 Build_Discriminal (Id);
17460 Discr_Number := Discr_Number + 1;
17463 Set_Has_Discriminants (Current_Scope);
17464 end Process_Discriminants;
17466 -----------------------
17467 -- Process_Full_View --
17468 -----------------------
17470 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
17471 Priv_Parent : Entity_Id;
17472 Full_Parent : Entity_Id;
17473 Full_Indic : Node_Id;
17475 procedure Collect_Implemented_Interfaces
17477 Ifaces : Elist_Id);
17478 -- Ada 2005: Gather all the interfaces that Typ directly or
17479 -- inherently implements. Duplicate entries are not added to
17480 -- the list Ifaces.
17482 ------------------------------------
17483 -- Collect_Implemented_Interfaces --
17484 ------------------------------------
17486 procedure Collect_Implemented_Interfaces
17491 Iface_Elmt : Elmt_Id;
17494 -- Abstract interfaces are only associated with tagged record types
17496 if not Is_Tagged_Type (Typ)
17497 or else not Is_Record_Type (Typ)
17502 -- Recursively climb to the ancestors
17504 if Etype (Typ) /= Typ
17506 -- Protect the frontend against wrong cyclic declarations like:
17508 -- type B is new A with private;
17509 -- type C is new A with private;
17511 -- type B is new C with null record;
17512 -- type C is new B with null record;
17514 and then Etype (Typ) /= Priv_T
17515 and then Etype (Typ) /= Full_T
17517 -- Keep separate the management of private type declarations
17519 if Ekind (Typ) = E_Record_Type_With_Private then
17521 -- Handle the following erroneous case:
17522 -- type Private_Type is tagged private;
17524 -- type Private_Type is new Type_Implementing_Iface;
17526 if Present (Full_View (Typ))
17527 and then Etype (Typ) /= Full_View (Typ)
17529 if Is_Interface (Etype (Typ)) then
17530 Append_Unique_Elmt (Etype (Typ), Ifaces);
17533 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
17536 -- Non-private types
17539 if Is_Interface (Etype (Typ)) then
17540 Append_Unique_Elmt (Etype (Typ), Ifaces);
17543 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
17547 -- Handle entities in the list of abstract interfaces
17549 if Present (Interfaces (Typ)) then
17550 Iface_Elmt := First_Elmt (Interfaces (Typ));
17551 while Present (Iface_Elmt) loop
17552 Iface := Node (Iface_Elmt);
17554 pragma Assert (Is_Interface (Iface));
17556 if not Contain_Interface (Iface, Ifaces) then
17557 Append_Elmt (Iface, Ifaces);
17558 Collect_Implemented_Interfaces (Iface, Ifaces);
17561 Next_Elmt (Iface_Elmt);
17564 end Collect_Implemented_Interfaces;
17566 -- Start of processing for Process_Full_View
17569 -- First some sanity checks that must be done after semantic
17570 -- decoration of the full view and thus cannot be placed with other
17571 -- similar checks in Find_Type_Name
17573 if not Is_Limited_Type (Priv_T)
17574 and then (Is_Limited_Type (Full_T)
17575 or else Is_Limited_Composite (Full_T))
17577 if In_Instance then
17581 ("completion of nonlimited type cannot be limited", Full_T);
17582 Explain_Limited_Type (Full_T, Full_T);
17585 elsif Is_Abstract_Type (Full_T)
17586 and then not Is_Abstract_Type (Priv_T)
17589 ("completion of nonabstract type cannot be abstract", Full_T);
17591 elsif Is_Tagged_Type (Priv_T)
17592 and then Is_Limited_Type (Priv_T)
17593 and then not Is_Limited_Type (Full_T)
17595 -- If pragma CPP_Class was applied to the private declaration
17596 -- propagate the limitedness to the full-view
17598 if Is_CPP_Class (Priv_T) then
17599 Set_Is_Limited_Record (Full_T);
17601 -- GNAT allow its own definition of Limited_Controlled to disobey
17602 -- this rule in order in ease the implementation. This test is safe
17603 -- because Root_Controlled is defined in a child of System that
17604 -- normal programs are not supposed to use.
17606 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
17607 Set_Is_Limited_Composite (Full_T);
17610 ("completion of limited tagged type must be limited", Full_T);
17613 elsif Is_Generic_Type (Priv_T) then
17614 Error_Msg_N ("generic type cannot have a completion", Full_T);
17617 -- Check that ancestor interfaces of private and full views are
17618 -- consistent. We omit this check for synchronized types because
17619 -- they are performed on the corresponding record type when frozen.
17621 if Ada_Version >= Ada_2005
17622 and then Is_Tagged_Type (Priv_T)
17623 and then Is_Tagged_Type (Full_T)
17624 and then not Is_Concurrent_Type (Full_T)
17628 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
17629 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
17632 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
17633 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
17635 -- Ada 2005 (AI-251): The partial view shall be a descendant of
17636 -- an interface type if and only if the full type is descendant
17637 -- of the interface type (AARM 7.3 (7.3/2)).
17639 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
17641 if Present (Iface) then
17643 ("interface & not implemented by full type " &
17644 "(RM-2005 7.3 (7.3/2))", Priv_T, Iface);
17647 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
17649 if Present (Iface) then
17651 ("interface & not implemented by partial view " &
17652 "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
17657 if Is_Tagged_Type (Priv_T)
17658 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
17659 and then Is_Derived_Type (Full_T)
17661 Priv_Parent := Etype (Priv_T);
17663 -- The full view of a private extension may have been transformed
17664 -- into an unconstrained derived type declaration and a subtype
17665 -- declaration (see build_derived_record_type for details).
17667 if Nkind (N) = N_Subtype_Declaration then
17668 Full_Indic := Subtype_Indication (N);
17669 Full_Parent := Etype (Base_Type (Full_T));
17671 Full_Indic := Subtype_Indication (Type_Definition (N));
17672 Full_Parent := Etype (Full_T);
17675 -- Check that the parent type of the full type is a descendant of
17676 -- the ancestor subtype given in the private extension. If either
17677 -- entity has an Etype equal to Any_Type then we had some previous
17678 -- error situation [7.3(8)].
17680 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
17683 -- Ada 2005 (AI-251): Interfaces in the full-typ can be given in
17684 -- any order. Therefore we don't have to check that its parent must
17685 -- be a descendant of the parent of the private type declaration.
17687 elsif Is_Interface (Priv_Parent)
17688 and then Is_Interface (Full_Parent)
17692 -- Ada 2005 (AI-251): If the parent of the private type declaration
17693 -- is an interface there is no need to check that it is an ancestor
17694 -- of the associated full type declaration. The required tests for
17695 -- this case are performed by Build_Derived_Record_Type.
17697 elsif not Is_Interface (Base_Type (Priv_Parent))
17698 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
17701 ("parent of full type must descend from parent"
17702 & " of private extension", Full_Indic);
17704 -- First check a formal restriction, and then proceed with checking
17705 -- Ada rules. Since the formal restriction is not a serious error, we
17706 -- don't prevent further error detection for this check, hence the
17711 -- In formal mode, when completing a private extension the type
17712 -- named in the private part must be exactly the same as that
17713 -- named in the visible part.
17715 if Priv_Parent /= Full_Parent then
17716 Error_Msg_Name_1 := Chars (Priv_Parent);
17717 Check_SPARK_Restriction ("% expected", Full_Indic);
17720 -- Check the rules of 7.3(10): if the private extension inherits
17721 -- known discriminants, then the full type must also inherit those
17722 -- discriminants from the same (ancestor) type, and the parent
17723 -- subtype of the full type must be constrained if and only if
17724 -- the ancestor subtype of the private extension is constrained.
17726 if No (Discriminant_Specifications (Parent (Priv_T)))
17727 and then not Has_Unknown_Discriminants (Priv_T)
17728 and then Has_Discriminants (Base_Type (Priv_Parent))
17731 Priv_Indic : constant Node_Id :=
17732 Subtype_Indication (Parent (Priv_T));
17734 Priv_Constr : constant Boolean :=
17735 Is_Constrained (Priv_Parent)
17737 Nkind (Priv_Indic) = N_Subtype_Indication
17739 Is_Constrained (Entity (Priv_Indic));
17741 Full_Constr : constant Boolean :=
17742 Is_Constrained (Full_Parent)
17744 Nkind (Full_Indic) = N_Subtype_Indication
17746 Is_Constrained (Entity (Full_Indic));
17748 Priv_Discr : Entity_Id;
17749 Full_Discr : Entity_Id;
17752 Priv_Discr := First_Discriminant (Priv_Parent);
17753 Full_Discr := First_Discriminant (Full_Parent);
17754 while Present (Priv_Discr) and then Present (Full_Discr) loop
17755 if Original_Record_Component (Priv_Discr) =
17756 Original_Record_Component (Full_Discr)
17758 Corresponding_Discriminant (Priv_Discr) =
17759 Corresponding_Discriminant (Full_Discr)
17766 Next_Discriminant (Priv_Discr);
17767 Next_Discriminant (Full_Discr);
17770 if Present (Priv_Discr) or else Present (Full_Discr) then
17772 ("full view must inherit discriminants of the parent"
17773 & " type used in the private extension", Full_Indic);
17775 elsif Priv_Constr and then not Full_Constr then
17777 ("parent subtype of full type must be constrained",
17780 elsif Full_Constr and then not Priv_Constr then
17782 ("parent subtype of full type must be unconstrained",
17787 -- Check the rules of 7.3(12): if a partial view has neither
17788 -- known or unknown discriminants, then the full type
17789 -- declaration shall define a definite subtype.
17791 elsif not Has_Unknown_Discriminants (Priv_T)
17792 and then not Has_Discriminants (Priv_T)
17793 and then not Is_Constrained (Full_T)
17796 ("full view must define a constrained type if partial view"
17797 & " has no discriminants", Full_T);
17800 -- ??????? Do we implement the following properly ?????
17801 -- If the ancestor subtype of a private extension has constrained
17802 -- discriminants, then the parent subtype of the full view shall
17803 -- impose a statically matching constraint on those discriminants
17808 -- For untagged types, verify that a type without discriminants
17809 -- is not completed with an unconstrained type.
17811 if not Is_Indefinite_Subtype (Priv_T)
17812 and then Is_Indefinite_Subtype (Full_T)
17814 Error_Msg_N ("full view of type must be definite subtype", Full_T);
17818 -- AI-419: verify that the use of "limited" is consistent
17821 Orig_Decl : constant Node_Id := Original_Node (N);
17824 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
17825 and then not Limited_Present (Parent (Priv_T))
17826 and then not Synchronized_Present (Parent (Priv_T))
17827 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
17829 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
17830 and then Limited_Present (Type_Definition (Orig_Decl))
17833 ("full view of non-limited extension cannot be limited", N);
17837 -- Ada 2005 (AI-443): A synchronized private extension must be
17838 -- completed by a task or protected type.
17840 if Ada_Version >= Ada_2005
17841 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
17842 and then Synchronized_Present (Parent (Priv_T))
17843 and then not Is_Concurrent_Type (Full_T)
17845 Error_Msg_N ("full view of synchronized extension must " &
17846 "be synchronized type", N);
17849 -- Ada 2005 AI-363: if the full view has discriminants with
17850 -- defaults, it is illegal to declare constrained access subtypes
17851 -- whose designated type is the current type. This allows objects
17852 -- of the type that are declared in the heap to be unconstrained.
17854 if not Has_Unknown_Discriminants (Priv_T)
17855 and then not Has_Discriminants (Priv_T)
17856 and then Has_Discriminants (Full_T)
17858 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
17860 Set_Has_Constrained_Partial_View (Full_T);
17861 Set_Has_Constrained_Partial_View (Priv_T);
17864 -- Create a full declaration for all its subtypes recorded in
17865 -- Private_Dependents and swap them similarly to the base type. These
17866 -- are subtypes that have been define before the full declaration of
17867 -- the private type. We also swap the entry in Private_Dependents list
17868 -- so we can properly restore the private view on exit from the scope.
17871 Priv_Elmt : Elmt_Id;
17876 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
17877 while Present (Priv_Elmt) loop
17878 Priv := Node (Priv_Elmt);
17880 if Ekind_In (Priv, E_Private_Subtype,
17881 E_Limited_Private_Subtype,
17882 E_Record_Subtype_With_Private)
17884 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
17885 Set_Is_Itype (Full);
17886 Set_Parent (Full, Parent (Priv));
17887 Set_Associated_Node_For_Itype (Full, N);
17889 -- Now we need to complete the private subtype, but since the
17890 -- base type has already been swapped, we must also swap the
17891 -- subtypes (and thus, reverse the arguments in the call to
17892 -- Complete_Private_Subtype).
17894 Copy_And_Swap (Priv, Full);
17895 Complete_Private_Subtype (Full, Priv, Full_T, N);
17896 Replace_Elmt (Priv_Elmt, Full);
17899 Next_Elmt (Priv_Elmt);
17903 -- If the private view was tagged, copy the new primitive operations
17904 -- from the private view to the full view.
17906 if Is_Tagged_Type (Full_T) then
17908 Disp_Typ : Entity_Id;
17909 Full_List : Elist_Id;
17911 Prim_Elmt : Elmt_Id;
17912 Priv_List : Elist_Id;
17916 L : Elist_Id) return Boolean;
17917 -- Determine whether list L contains element E
17925 L : Elist_Id) return Boolean
17927 List_Elmt : Elmt_Id;
17930 List_Elmt := First_Elmt (L);
17931 while Present (List_Elmt) loop
17932 if Node (List_Elmt) = E then
17936 Next_Elmt (List_Elmt);
17942 -- Start of processing
17945 if Is_Tagged_Type (Priv_T) then
17946 Priv_List := Primitive_Operations (Priv_T);
17947 Prim_Elmt := First_Elmt (Priv_List);
17949 -- In the case of a concurrent type completing a private tagged
17950 -- type, primitives may have been declared in between the two
17951 -- views. These subprograms need to be wrapped the same way
17952 -- entries and protected procedures are handled because they
17953 -- cannot be directly shared by the two views.
17955 if Is_Concurrent_Type (Full_T) then
17957 Conc_Typ : constant Entity_Id :=
17958 Corresponding_Record_Type (Full_T);
17959 Curr_Nod : Node_Id := Parent (Conc_Typ);
17960 Wrap_Spec : Node_Id;
17963 while Present (Prim_Elmt) loop
17964 Prim := Node (Prim_Elmt);
17966 if Comes_From_Source (Prim)
17967 and then not Is_Abstract_Subprogram (Prim)
17970 Make_Subprogram_Declaration (Sloc (Prim),
17974 Obj_Typ => Conc_Typ,
17976 Parameter_Specifications (
17979 Insert_After (Curr_Nod, Wrap_Spec);
17980 Curr_Nod := Wrap_Spec;
17982 Analyze (Wrap_Spec);
17985 Next_Elmt (Prim_Elmt);
17991 -- For non-concurrent types, transfer explicit primitives, but
17992 -- omit those inherited from the parent of the private view
17993 -- since they will be re-inherited later on.
17996 Full_List := Primitive_Operations (Full_T);
17998 while Present (Prim_Elmt) loop
17999 Prim := Node (Prim_Elmt);
18001 if Comes_From_Source (Prim)
18002 and then not Contains (Prim, Full_List)
18004 Append_Elmt (Prim, Full_List);
18007 Next_Elmt (Prim_Elmt);
18011 -- Untagged private view
18014 Full_List := Primitive_Operations (Full_T);
18016 -- In this case the partial view is untagged, so here we locate
18017 -- all of the earlier primitives that need to be treated as
18018 -- dispatching (those that appear between the two views). Note
18019 -- that these additional operations must all be new operations
18020 -- (any earlier operations that override inherited operations
18021 -- of the full view will already have been inserted in the
18022 -- primitives list, marked by Check_Operation_From_Private_View
18023 -- as dispatching. Note that implicit "/=" operators are
18024 -- excluded from being added to the primitives list since they
18025 -- shouldn't be treated as dispatching (tagged "/=" is handled
18028 Prim := Next_Entity (Full_T);
18029 while Present (Prim) and then Prim /= Priv_T loop
18030 if Ekind_In (Prim, E_Procedure, E_Function) then
18031 Disp_Typ := Find_Dispatching_Type (Prim);
18033 if Disp_Typ = Full_T
18034 and then (Chars (Prim) /= Name_Op_Ne
18035 or else Comes_From_Source (Prim))
18037 Check_Controlling_Formals (Full_T, Prim);
18039 if not Is_Dispatching_Operation (Prim) then
18040 Append_Elmt (Prim, Full_List);
18041 Set_Is_Dispatching_Operation (Prim, True);
18042 Set_DT_Position (Prim, No_Uint);
18045 elsif Is_Dispatching_Operation (Prim)
18046 and then Disp_Typ /= Full_T
18049 -- Verify that it is not otherwise controlled by a
18050 -- formal or a return value of type T.
18052 Check_Controlling_Formals (Disp_Typ, Prim);
18056 Next_Entity (Prim);
18060 -- For the tagged case, the two views can share the same primitive
18061 -- operations list and the same class-wide type. Update attributes
18062 -- of the class-wide type which depend on the full declaration.
18064 if Is_Tagged_Type (Priv_T) then
18065 Set_Direct_Primitive_Operations (Priv_T, Full_List);
18066 Set_Class_Wide_Type
18067 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
18069 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
18074 -- Ada 2005 AI 161: Check preelaboratable initialization consistency
18076 if Known_To_Have_Preelab_Init (Priv_T) then
18078 -- Case where there is a pragma Preelaborable_Initialization. We
18079 -- always allow this in predefined units, which is a bit of a kludge,
18080 -- but it means we don't have to struggle to meet the requirements in
18081 -- the RM for having Preelaborable Initialization. Otherwise we
18082 -- require that the type meets the RM rules. But we can't check that
18083 -- yet, because of the rule about overriding Initialize, so we simply
18084 -- set a flag that will be checked at freeze time.
18086 if not In_Predefined_Unit (Full_T) then
18087 Set_Must_Have_Preelab_Init (Full_T);
18091 -- If pragma CPP_Class was applied to the private type declaration,
18092 -- propagate it now to the full type declaration.
18094 if Is_CPP_Class (Priv_T) then
18095 Set_Is_CPP_Class (Full_T);
18096 Set_Convention (Full_T, Convention_CPP);
18099 -- If the private view has user specified stream attributes, then so has
18102 -- Why the test, how could these flags be already set in Full_T ???
18104 if Has_Specified_Stream_Read (Priv_T) then
18105 Set_Has_Specified_Stream_Read (Full_T);
18108 if Has_Specified_Stream_Write (Priv_T) then
18109 Set_Has_Specified_Stream_Write (Full_T);
18112 if Has_Specified_Stream_Input (Priv_T) then
18113 Set_Has_Specified_Stream_Input (Full_T);
18116 if Has_Specified_Stream_Output (Priv_T) then
18117 Set_Has_Specified_Stream_Output (Full_T);
18120 -- Propagate invariants to full type
18122 if Has_Invariants (Priv_T) then
18123 Set_Has_Invariants (Full_T);
18124 Set_Invariant_Procedure (Full_T, Invariant_Procedure (Priv_T));
18127 if Has_Inheritable_Invariants (Priv_T) then
18128 Set_Has_Inheritable_Invariants (Full_T);
18131 -- Propagate predicates to full type
18133 if Has_Predicates (Priv_T) then
18134 Set_Predicate_Function (Priv_T, Predicate_Function (Full_T));
18135 Set_Has_Predicates (Priv_T);
18137 end Process_Full_View;
18139 -----------------------------------
18140 -- Process_Incomplete_Dependents --
18141 -----------------------------------
18143 procedure Process_Incomplete_Dependents
18145 Full_T : Entity_Id;
18148 Inc_Elmt : Elmt_Id;
18149 Priv_Dep : Entity_Id;
18150 New_Subt : Entity_Id;
18152 Disc_Constraint : Elist_Id;
18155 if No (Private_Dependents (Inc_T)) then
18159 -- Itypes that may be generated by the completion of an incomplete
18160 -- subtype are not used by the back-end and not attached to the tree.
18161 -- They are created only for constraint-checking purposes.
18163 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
18164 while Present (Inc_Elmt) loop
18165 Priv_Dep := Node (Inc_Elmt);
18167 if Ekind (Priv_Dep) = E_Subprogram_Type then
18169 -- An Access_To_Subprogram type may have a return type or a
18170 -- parameter type that is incomplete. Replace with the full view.
18172 if Etype (Priv_Dep) = Inc_T then
18173 Set_Etype (Priv_Dep, Full_T);
18177 Formal : Entity_Id;
18180 Formal := First_Formal (Priv_Dep);
18181 while Present (Formal) loop
18182 if Etype (Formal) = Inc_T then
18183 Set_Etype (Formal, Full_T);
18186 Next_Formal (Formal);
18190 elsif Is_Overloadable (Priv_Dep) then
18192 -- If a subprogram in the incomplete dependents list is primitive
18193 -- for a tagged full type then mark it as a dispatching operation,
18194 -- check whether it overrides an inherited subprogram, and check
18195 -- restrictions on its controlling formals. Note that a protected
18196 -- operation is never dispatching: only its wrapper operation
18197 -- (which has convention Ada) is.
18199 if Is_Tagged_Type (Full_T)
18200 and then Is_Primitive (Priv_Dep)
18201 and then Convention (Priv_Dep) /= Convention_Protected
18203 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
18204 Set_Is_Dispatching_Operation (Priv_Dep);
18205 Check_Controlling_Formals (Full_T, Priv_Dep);
18208 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
18210 -- Can happen during processing of a body before the completion
18211 -- of a TA type. Ignore, because spec is also on dependent list.
18215 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
18216 -- corresponding subtype of the full view.
18218 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
18219 Set_Subtype_Indication
18220 (Parent (Priv_Dep), New_Reference_To (Full_T, Sloc (Priv_Dep)));
18221 Set_Etype (Priv_Dep, Full_T);
18222 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
18223 Set_Analyzed (Parent (Priv_Dep), False);
18225 -- Reanalyze the declaration, suppressing the call to
18226 -- Enter_Name to avoid duplicate names.
18228 Analyze_Subtype_Declaration
18229 (N => Parent (Priv_Dep),
18232 -- Dependent is a subtype
18235 -- We build a new subtype indication using the full view of the
18236 -- incomplete parent. The discriminant constraints have been
18237 -- elaborated already at the point of the subtype declaration.
18239 New_Subt := Create_Itype (E_Void, N);
18241 if Has_Discriminants (Full_T) then
18242 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
18244 Disc_Constraint := No_Elist;
18247 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
18248 Set_Full_View (Priv_Dep, New_Subt);
18251 Next_Elmt (Inc_Elmt);
18253 end Process_Incomplete_Dependents;
18255 --------------------------------
18256 -- Process_Range_Expr_In_Decl --
18257 --------------------------------
18259 procedure Process_Range_Expr_In_Decl
18262 Check_List : List_Id := Empty_List;
18263 R_Check_Off : Boolean := False;
18264 In_Iter_Schm : Boolean := False)
18267 R_Checks : Check_Result;
18268 Insert_Node : Node_Id;
18269 Def_Id : Entity_Id;
18272 Analyze_And_Resolve (R, Base_Type (T));
18274 if Nkind (R) = N_Range then
18276 -- In SPARK, all ranges should be static, with the exception of the
18277 -- discrete type definition of a loop parameter specification.
18279 if not In_Iter_Schm
18280 and then not Is_Static_Range (R)
18282 Check_SPARK_Restriction ("range should be static", R);
18285 Lo := Low_Bound (R);
18286 Hi := High_Bound (R);
18288 -- We need to ensure validity of the bounds here, because if we
18289 -- go ahead and do the expansion, then the expanded code will get
18290 -- analyzed with range checks suppressed and we miss the check.
18292 Validity_Check_Range (R);
18294 -- If there were errors in the declaration, try and patch up some
18295 -- common mistakes in the bounds. The cases handled are literals
18296 -- which are Integer where the expected type is Real and vice versa.
18297 -- These corrections allow the compilation process to proceed further
18298 -- along since some basic assumptions of the format of the bounds
18301 if Etype (R) = Any_Type then
18303 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
18305 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
18307 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
18309 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
18311 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
18313 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
18315 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
18317 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
18324 -- If the bounds of the range have been mistakenly given as string
18325 -- literals (perhaps in place of character literals), then an error
18326 -- has already been reported, but we rewrite the string literal as a
18327 -- bound of the range's type to avoid blowups in later processing
18328 -- that looks at static values.
18330 if Nkind (Lo) = N_String_Literal then
18332 Make_Attribute_Reference (Sloc (Lo),
18333 Attribute_Name => Name_First,
18334 Prefix => New_Reference_To (T, Sloc (Lo))));
18335 Analyze_And_Resolve (Lo);
18338 if Nkind (Hi) = N_String_Literal then
18340 Make_Attribute_Reference (Sloc (Hi),
18341 Attribute_Name => Name_First,
18342 Prefix => New_Reference_To (T, Sloc (Hi))));
18343 Analyze_And_Resolve (Hi);
18346 -- If bounds aren't scalar at this point then exit, avoiding
18347 -- problems with further processing of the range in this procedure.
18349 if not Is_Scalar_Type (Etype (Lo)) then
18353 -- Resolve (actually Sem_Eval) has checked that the bounds are in
18354 -- then range of the base type. Here we check whether the bounds
18355 -- are in the range of the subtype itself. Note that if the bounds
18356 -- represent the null range the Constraint_Error exception should
18359 -- ??? The following code should be cleaned up as follows
18361 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
18362 -- is done in the call to Range_Check (R, T); below
18364 -- 2. The use of R_Check_Off should be investigated and possibly
18365 -- removed, this would clean up things a bit.
18367 if Is_Null_Range (Lo, Hi) then
18371 -- Capture values of bounds and generate temporaries for them
18372 -- if needed, before applying checks, since checks may cause
18373 -- duplication of the expression without forcing evaluation.
18375 -- The forced evaluation removes side effects from expressions,
18376 -- which should occur also in Alfa mode. Otherwise, we end up with
18377 -- unexpected insertions of actions at places where this is not
18378 -- supposed to occur, e.g. on default parameters of a call.
18380 if Expander_Active then
18381 Force_Evaluation (Lo);
18382 Force_Evaluation (Hi);
18385 -- We use a flag here instead of suppressing checks on the
18386 -- type because the type we check against isn't necessarily
18387 -- the place where we put the check.
18389 if not R_Check_Off then
18390 R_Checks := Get_Range_Checks (R, T);
18392 -- Look up tree to find an appropriate insertion point. We
18393 -- can't just use insert_actions because later processing
18394 -- depends on the insertion node. Prior to Ada 2012 the
18395 -- insertion point could only be a declaration or a loop, but
18396 -- quantified expressions can appear within any context in an
18397 -- expression, and the insertion point can be any statement,
18398 -- pragma, or declaration.
18400 Insert_Node := Parent (R);
18401 while Present (Insert_Node) loop
18403 Nkind (Insert_Node) in N_Declaration
18406 (Insert_Node, N_Component_Declaration,
18407 N_Loop_Parameter_Specification,
18408 N_Function_Specification,
18409 N_Procedure_Specification);
18411 exit when Nkind (Insert_Node) in N_Later_Decl_Item
18412 or else Nkind (Insert_Node) in
18413 N_Statement_Other_Than_Procedure_Call
18414 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
18417 Insert_Node := Parent (Insert_Node);
18420 -- Why would Type_Decl not be present??? Without this test,
18421 -- short regression tests fail.
18423 if Present (Insert_Node) then
18425 -- Case of loop statement. Verify that the range is part
18426 -- of the subtype indication of the iteration scheme.
18428 if Nkind (Insert_Node) = N_Loop_Statement then
18433 Indic := Parent (R);
18434 while Present (Indic)
18435 and then Nkind (Indic) /= N_Subtype_Indication
18437 Indic := Parent (Indic);
18440 if Present (Indic) then
18441 Def_Id := Etype (Subtype_Mark (Indic));
18443 Insert_Range_Checks
18447 Sloc (Insert_Node),
18449 Do_Before => True);
18453 -- Insertion before a declaration. If the declaration
18454 -- includes discriminants, the list of applicable checks
18455 -- is given by the caller.
18457 elsif Nkind (Insert_Node) in N_Declaration then
18458 Def_Id := Defining_Identifier (Insert_Node);
18460 if (Ekind (Def_Id) = E_Record_Type
18461 and then Depends_On_Discriminant (R))
18463 (Ekind (Def_Id) = E_Protected_Type
18464 and then Has_Discriminants (Def_Id))
18466 Append_Range_Checks
18468 Check_List, Def_Id, Sloc (Insert_Node), R);
18471 Insert_Range_Checks
18473 Insert_Node, Def_Id, Sloc (Insert_Node), R);
18477 -- Insertion before a statement. Range appears in the
18478 -- context of a quantified expression. Insertion will
18479 -- take place when expression is expanded.
18488 -- Case of other than an explicit N_Range node
18490 -- The forced evaluation removes side effects from expressions, which
18491 -- should occur also in Alfa mode. Otherwise, we end up with unexpected
18492 -- insertions of actions at places where this is not supposed to occur,
18493 -- e.g. on default parameters of a call.
18495 elsif Expander_Active then
18496 Get_Index_Bounds (R, Lo, Hi);
18497 Force_Evaluation (Lo);
18498 Force_Evaluation (Hi);
18500 end Process_Range_Expr_In_Decl;
18502 --------------------------------------
18503 -- Process_Real_Range_Specification --
18504 --------------------------------------
18506 procedure Process_Real_Range_Specification (Def : Node_Id) is
18507 Spec : constant Node_Id := Real_Range_Specification (Def);
18510 Err : Boolean := False;
18512 procedure Analyze_Bound (N : Node_Id);
18513 -- Analyze and check one bound
18515 -------------------
18516 -- Analyze_Bound --
18517 -------------------
18519 procedure Analyze_Bound (N : Node_Id) is
18521 Analyze_And_Resolve (N, Any_Real);
18523 if not Is_OK_Static_Expression (N) then
18524 Flag_Non_Static_Expr
18525 ("bound in real type definition is not static!", N);
18530 -- Start of processing for Process_Real_Range_Specification
18533 if Present (Spec) then
18534 Lo := Low_Bound (Spec);
18535 Hi := High_Bound (Spec);
18536 Analyze_Bound (Lo);
18537 Analyze_Bound (Hi);
18539 -- If error, clear away junk range specification
18542 Set_Real_Range_Specification (Def, Empty);
18545 end Process_Real_Range_Specification;
18547 ---------------------
18548 -- Process_Subtype --
18549 ---------------------
18551 function Process_Subtype
18553 Related_Nod : Node_Id;
18554 Related_Id : Entity_Id := Empty;
18555 Suffix : Character := ' ') return Entity_Id
18558 Def_Id : Entity_Id;
18559 Error_Node : Node_Id;
18560 Full_View_Id : Entity_Id;
18561 Subtype_Mark_Id : Entity_Id;
18563 May_Have_Null_Exclusion : Boolean;
18565 procedure Check_Incomplete (T : Entity_Id);
18566 -- Called to verify that an incomplete type is not used prematurely
18568 ----------------------
18569 -- Check_Incomplete --
18570 ----------------------
18572 procedure Check_Incomplete (T : Entity_Id) is
18574 -- Ada 2005 (AI-412): Incomplete subtypes are legal
18576 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
18578 not (Ada_Version >= Ada_2005
18580 (Nkind (Parent (T)) = N_Subtype_Declaration
18582 (Nkind (Parent (T)) = N_Subtype_Indication
18583 and then Nkind (Parent (Parent (T))) =
18584 N_Subtype_Declaration)))
18586 Error_Msg_N ("invalid use of type before its full declaration", T);
18588 end Check_Incomplete;
18590 -- Start of processing for Process_Subtype
18593 -- Case of no constraints present
18595 if Nkind (S) /= N_Subtype_Indication then
18597 Check_Incomplete (S);
18600 -- Ada 2005 (AI-231): Static check
18602 if Ada_Version >= Ada_2005
18603 and then Present (P)
18604 and then Null_Exclusion_Present (P)
18605 and then Nkind (P) /= N_Access_To_Object_Definition
18606 and then not Is_Access_Type (Entity (S))
18608 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
18611 -- The following is ugly, can't we have a range or even a flag???
18613 May_Have_Null_Exclusion :=
18614 Nkind_In (P, N_Access_Definition,
18615 N_Access_Function_Definition,
18616 N_Access_Procedure_Definition,
18617 N_Access_To_Object_Definition,
18619 N_Component_Definition)
18621 Nkind_In (P, N_Derived_Type_Definition,
18622 N_Discriminant_Specification,
18623 N_Formal_Object_Declaration,
18624 N_Object_Declaration,
18625 N_Object_Renaming_Declaration,
18626 N_Parameter_Specification,
18627 N_Subtype_Declaration);
18629 -- Create an Itype that is a duplicate of Entity (S) but with the
18630 -- null-exclusion attribute.
18632 if May_Have_Null_Exclusion
18633 and then Is_Access_Type (Entity (S))
18634 and then Null_Exclusion_Present (P)
18636 -- No need to check the case of an access to object definition.
18637 -- It is correct to define double not-null pointers.
18640 -- type Not_Null_Int_Ptr is not null access Integer;
18641 -- type Acc is not null access Not_Null_Int_Ptr;
18643 and then Nkind (P) /= N_Access_To_Object_Definition
18645 if Can_Never_Be_Null (Entity (S)) then
18646 case Nkind (Related_Nod) is
18647 when N_Full_Type_Declaration =>
18648 if Nkind (Type_Definition (Related_Nod))
18649 in N_Array_Type_Definition
18653 (Component_Definition
18654 (Type_Definition (Related_Nod)));
18657 Subtype_Indication (Type_Definition (Related_Nod));
18660 when N_Subtype_Declaration =>
18661 Error_Node := Subtype_Indication (Related_Nod);
18663 when N_Object_Declaration =>
18664 Error_Node := Object_Definition (Related_Nod);
18666 when N_Component_Declaration =>
18668 Subtype_Indication (Component_Definition (Related_Nod));
18670 when N_Allocator =>
18671 Error_Node := Expression (Related_Nod);
18674 pragma Assert (False);
18675 Error_Node := Related_Nod;
18679 ("`NOT NULL` not allowed (& already excludes null)",
18685 Create_Null_Excluding_Itype
18687 Related_Nod => P));
18688 Set_Entity (S, Etype (S));
18693 -- Case of constraint present, so that we have an N_Subtype_Indication
18694 -- node (this node is created only if constraints are present).
18697 Find_Type (Subtype_Mark (S));
18699 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
18701 (Nkind (Parent (S)) = N_Subtype_Declaration
18702 and then Is_Itype (Defining_Identifier (Parent (S))))
18704 Check_Incomplete (Subtype_Mark (S));
18708 Subtype_Mark_Id := Entity (Subtype_Mark (S));
18710 -- Explicit subtype declaration case
18712 if Nkind (P) = N_Subtype_Declaration then
18713 Def_Id := Defining_Identifier (P);
18715 -- Explicit derived type definition case
18717 elsif Nkind (P) = N_Derived_Type_Definition then
18718 Def_Id := Defining_Identifier (Parent (P));
18720 -- Implicit case, the Def_Id must be created as an implicit type.
18721 -- The one exception arises in the case of concurrent types, array
18722 -- and access types, where other subsidiary implicit types may be
18723 -- created and must appear before the main implicit type. In these
18724 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
18725 -- has not yet been called to create Def_Id.
18728 if Is_Array_Type (Subtype_Mark_Id)
18729 or else Is_Concurrent_Type (Subtype_Mark_Id)
18730 or else Is_Access_Type (Subtype_Mark_Id)
18734 -- For the other cases, we create a new unattached Itype,
18735 -- and set the indication to ensure it gets attached later.
18739 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
18743 -- If the kind of constraint is invalid for this kind of type,
18744 -- then give an error, and then pretend no constraint was given.
18746 if not Is_Valid_Constraint_Kind
18747 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
18750 ("incorrect constraint for this kind of type", Constraint (S));
18752 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
18754 -- Set Ekind of orphan itype, to prevent cascaded errors
18756 if Present (Def_Id) then
18757 Set_Ekind (Def_Id, Ekind (Any_Type));
18760 -- Make recursive call, having got rid of the bogus constraint
18762 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
18765 -- Remaining processing depends on type. Select on Base_Type kind to
18766 -- ensure getting to the concrete type kind in the case of a private
18767 -- subtype (needed when only doing semantic analysis).
18769 case Ekind (Base_Type (Subtype_Mark_Id)) is
18770 when Access_Kind =>
18771 Constrain_Access (Def_Id, S, Related_Nod);
18774 and then Is_Itype (Designated_Type (Def_Id))
18775 and then Nkind (Related_Nod) = N_Subtype_Declaration
18776 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
18778 Build_Itype_Reference
18779 (Designated_Type (Def_Id), Related_Nod);
18783 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
18785 when Decimal_Fixed_Point_Kind =>
18786 Constrain_Decimal (Def_Id, S);
18788 when Enumeration_Kind =>
18789 Constrain_Enumeration (Def_Id, S);
18791 when Ordinary_Fixed_Point_Kind =>
18792 Constrain_Ordinary_Fixed (Def_Id, S);
18795 Constrain_Float (Def_Id, S);
18797 when Integer_Kind =>
18798 Constrain_Integer (Def_Id, S);
18800 when E_Record_Type |
18803 E_Incomplete_Type =>
18804 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
18806 if Ekind (Def_Id) = E_Incomplete_Type then
18807 Set_Private_Dependents (Def_Id, New_Elmt_List);
18810 when Private_Kind =>
18811 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
18812 Set_Private_Dependents (Def_Id, New_Elmt_List);
18814 -- In case of an invalid constraint prevent further processing
18815 -- since the type constructed is missing expected fields.
18817 if Etype (Def_Id) = Any_Type then
18821 -- If the full view is that of a task with discriminants,
18822 -- we must constrain both the concurrent type and its
18823 -- corresponding record type. Otherwise we will just propagate
18824 -- the constraint to the full view, if available.
18826 if Present (Full_View (Subtype_Mark_Id))
18827 and then Has_Discriminants (Subtype_Mark_Id)
18828 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
18831 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
18833 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
18834 Constrain_Concurrent (Full_View_Id, S,
18835 Related_Nod, Related_Id, Suffix);
18836 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
18837 Set_Full_View (Def_Id, Full_View_Id);
18839 -- Introduce an explicit reference to the private subtype,
18840 -- to prevent scope anomalies in gigi if first use appears
18841 -- in a nested context, e.g. a later function body.
18842 -- Should this be generated in other contexts than a full
18843 -- type declaration?
18845 if Is_Itype (Def_Id)
18847 Nkind (Parent (P)) = N_Full_Type_Declaration
18849 Build_Itype_Reference (Def_Id, Parent (P));
18853 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
18856 when Concurrent_Kind =>
18857 Constrain_Concurrent (Def_Id, S,
18858 Related_Nod, Related_Id, Suffix);
18861 Error_Msg_N ("invalid subtype mark in subtype indication", S);
18864 -- Size and Convention are always inherited from the base type
18866 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
18867 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
18871 end Process_Subtype;
18873 ---------------------------------------
18874 -- Check_Anonymous_Access_Components --
18875 ---------------------------------------
18877 procedure Check_Anonymous_Access_Components
18878 (Typ_Decl : Node_Id;
18881 Comp_List : Node_Id)
18883 Loc : constant Source_Ptr := Sloc (Typ_Decl);
18884 Anon_Access : Entity_Id;
18887 Comp_Def : Node_Id;
18889 Type_Def : Node_Id;
18891 procedure Build_Incomplete_Type_Declaration;
18892 -- If the record type contains components that include an access to the
18893 -- current record, then create an incomplete type declaration for the
18894 -- record, to be used as the designated type of the anonymous access.
18895 -- This is done only once, and only if there is no previous partial
18896 -- view of the type.
18898 function Designates_T (Subt : Node_Id) return Boolean;
18899 -- Check whether a node designates the enclosing record type, or 'Class
18902 function Mentions_T (Acc_Def : Node_Id) return Boolean;
18903 -- Check whether an access definition includes a reference to
18904 -- the enclosing record type. The reference can be a subtype mark
18905 -- in the access definition itself, a 'Class attribute reference, or
18906 -- recursively a reference appearing in a parameter specification
18907 -- or result definition of an access_to_subprogram definition.
18909 --------------------------------------
18910 -- Build_Incomplete_Type_Declaration --
18911 --------------------------------------
18913 procedure Build_Incomplete_Type_Declaration is
18918 -- Is_Tagged indicates whether the type is tagged. It is tagged if
18919 -- it's "is new ... with record" or else "is tagged record ...".
18921 Is_Tagged : constant Boolean :=
18922 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
18925 (Record_Extension_Part (Type_Definition (Typ_Decl))))
18927 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
18928 and then Tagged_Present (Type_Definition (Typ_Decl)));
18931 -- If there is a previous partial view, no need to create a new one
18932 -- If the partial view, given by Prev, is incomplete, If Prev is
18933 -- a private declaration, full declaration is flagged accordingly.
18935 if Prev /= Typ then
18937 Make_Class_Wide_Type (Prev);
18938 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
18939 Set_Etype (Class_Wide_Type (Typ), Typ);
18944 elsif Has_Private_Declaration (Typ) then
18946 -- If we refer to T'Class inside T, and T is the completion of a
18947 -- private type, then we need to make sure the class-wide type
18951 Make_Class_Wide_Type (Typ);
18956 -- If there was a previous anonymous access type, the incomplete
18957 -- type declaration will have been created already.
18959 elsif Present (Current_Entity (Typ))
18960 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
18961 and then Full_View (Current_Entity (Typ)) = Typ
18964 and then Comes_From_Source (Current_Entity (Typ))
18965 and then not Is_Tagged_Type (Current_Entity (Typ))
18967 Make_Class_Wide_Type (Typ);
18969 ("incomplete view of tagged type should be declared tagged?",
18970 Parent (Current_Entity (Typ)));
18975 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
18976 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
18978 -- Type has already been inserted into the current scope. Remove
18979 -- it, and add incomplete declaration for type, so that subsequent
18980 -- anonymous access types can use it. The entity is unchained from
18981 -- the homonym list and from immediate visibility. After analysis,
18982 -- the entity in the incomplete declaration becomes immediately
18983 -- visible in the record declaration that follows.
18985 H := Current_Entity (Typ);
18988 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
18991 and then Homonym (H) /= Typ
18993 H := Homonym (Typ);
18996 Set_Homonym (H, Homonym (Typ));
18999 Insert_Before (Typ_Decl, Decl);
19001 Set_Full_View (Inc_T, Typ);
19005 -- Create a common class-wide type for both views, and set the
19006 -- Etype of the class-wide type to the full view.
19008 Make_Class_Wide_Type (Inc_T);
19009 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
19010 Set_Etype (Class_Wide_Type (Typ), Typ);
19013 end Build_Incomplete_Type_Declaration;
19019 function Designates_T (Subt : Node_Id) return Boolean is
19020 Type_Id : constant Name_Id := Chars (Typ);
19022 function Names_T (Nam : Node_Id) return Boolean;
19023 -- The record type has not been introduced in the current scope
19024 -- yet, so we must examine the name of the type itself, either
19025 -- an identifier T, or an expanded name of the form P.T, where
19026 -- P denotes the current scope.
19032 function Names_T (Nam : Node_Id) return Boolean is
19034 if Nkind (Nam) = N_Identifier then
19035 return Chars (Nam) = Type_Id;
19037 elsif Nkind (Nam) = N_Selected_Component then
19038 if Chars (Selector_Name (Nam)) = Type_Id then
19039 if Nkind (Prefix (Nam)) = N_Identifier then
19040 return Chars (Prefix (Nam)) = Chars (Current_Scope);
19042 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
19043 return Chars (Selector_Name (Prefix (Nam))) =
19044 Chars (Current_Scope);
19058 -- Start of processing for Designates_T
19061 if Nkind (Subt) = N_Identifier then
19062 return Chars (Subt) = Type_Id;
19064 -- Reference can be through an expanded name which has not been
19065 -- analyzed yet, and which designates enclosing scopes.
19067 elsif Nkind (Subt) = N_Selected_Component then
19068 if Names_T (Subt) then
19071 -- Otherwise it must denote an entity that is already visible.
19072 -- The access definition may name a subtype of the enclosing
19073 -- type, if there is a previous incomplete declaration for it.
19076 Find_Selected_Component (Subt);
19078 Is_Entity_Name (Subt)
19079 and then Scope (Entity (Subt)) = Current_Scope
19081 (Chars (Base_Type (Entity (Subt))) = Type_Id
19083 (Is_Class_Wide_Type (Entity (Subt))
19085 Chars (Etype (Base_Type (Entity (Subt)))) =
19089 -- A reference to the current type may appear as the prefix of
19090 -- a 'Class attribute.
19092 elsif Nkind (Subt) = N_Attribute_Reference
19093 and then Attribute_Name (Subt) = Name_Class
19095 return Names_T (Prefix (Subt));
19106 function Mentions_T (Acc_Def : Node_Id) return Boolean is
19107 Param_Spec : Node_Id;
19109 Acc_Subprg : constant Node_Id :=
19110 Access_To_Subprogram_Definition (Acc_Def);
19113 if No (Acc_Subprg) then
19114 return Designates_T (Subtype_Mark (Acc_Def));
19117 -- Component is an access_to_subprogram: examine its formals,
19118 -- and result definition in the case of an access_to_function.
19120 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
19121 while Present (Param_Spec) loop
19122 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
19123 and then Mentions_T (Parameter_Type (Param_Spec))
19127 elsif Designates_T (Parameter_Type (Param_Spec)) then
19134 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
19135 if Nkind (Result_Definition (Acc_Subprg)) =
19136 N_Access_Definition
19138 return Mentions_T (Result_Definition (Acc_Subprg));
19140 return Designates_T (Result_Definition (Acc_Subprg));
19147 -- Start of processing for Check_Anonymous_Access_Components
19150 if No (Comp_List) then
19154 Comp := First (Component_Items (Comp_List));
19155 while Present (Comp) loop
19156 if Nkind (Comp) = N_Component_Declaration
19158 (Access_Definition (Component_Definition (Comp)))
19160 Mentions_T (Access_Definition (Component_Definition (Comp)))
19162 Comp_Def := Component_Definition (Comp);
19164 Access_To_Subprogram_Definition
19165 (Access_Definition (Comp_Def));
19167 Build_Incomplete_Type_Declaration;
19168 Anon_Access := Make_Temporary (Loc, 'S');
19170 -- Create a declaration for the anonymous access type: either
19171 -- an access_to_object or an access_to_subprogram.
19173 if Present (Acc_Def) then
19174 if Nkind (Acc_Def) = N_Access_Function_Definition then
19176 Make_Access_Function_Definition (Loc,
19177 Parameter_Specifications =>
19178 Parameter_Specifications (Acc_Def),
19179 Result_Definition => Result_Definition (Acc_Def));
19182 Make_Access_Procedure_Definition (Loc,
19183 Parameter_Specifications =>
19184 Parameter_Specifications (Acc_Def));
19189 Make_Access_To_Object_Definition (Loc,
19190 Subtype_Indication =>
19193 (Access_Definition (Comp_Def))));
19195 Set_Constant_Present
19196 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
19198 (Type_Def, All_Present (Access_Definition (Comp_Def)));
19201 Set_Null_Exclusion_Present
19203 Null_Exclusion_Present (Access_Definition (Comp_Def)));
19206 Make_Full_Type_Declaration (Loc,
19207 Defining_Identifier => Anon_Access,
19208 Type_Definition => Type_Def);
19210 Insert_Before (Typ_Decl, Decl);
19213 -- If an access to subprogram, create the extra formals
19215 if Present (Acc_Def) then
19216 Create_Extra_Formals (Designated_Type (Anon_Access));
19218 -- If an access to object, preserve entity of designated type,
19219 -- for ASIS use, before rewriting the component definition.
19226 Desig := Entity (Subtype_Indication (Type_Def));
19228 -- If the access definition is to the current record,
19229 -- the visible entity at this point is an incomplete
19230 -- type. Retrieve the full view to simplify ASIS queries
19232 if Ekind (Desig) = E_Incomplete_Type then
19233 Desig := Full_View (Desig);
19237 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
19242 Make_Component_Definition (Loc,
19243 Subtype_Indication =>
19244 New_Occurrence_Of (Anon_Access, Loc)));
19246 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
19247 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
19249 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
19252 Set_Is_Local_Anonymous_Access (Anon_Access);
19258 if Present (Variant_Part (Comp_List)) then
19262 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
19263 while Present (V) loop
19264 Check_Anonymous_Access_Components
19265 (Typ_Decl, Typ, Prev, Component_List (V));
19266 Next_Non_Pragma (V);
19270 end Check_Anonymous_Access_Components;
19272 --------------------------------
19273 -- Preanalyze_Spec_Expression --
19274 --------------------------------
19276 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
19277 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
19279 In_Spec_Expression := True;
19280 Preanalyze_And_Resolve (N, T);
19281 In_Spec_Expression := Save_In_Spec_Expression;
19282 end Preanalyze_Spec_Expression;
19284 -----------------------------
19285 -- Record_Type_Declaration --
19286 -----------------------------
19288 procedure Record_Type_Declaration
19293 Def : constant Node_Id := Type_Definition (N);
19294 Is_Tagged : Boolean;
19295 Tag_Comp : Entity_Id;
19298 -- These flags must be initialized before calling Process_Discriminants
19299 -- because this routine makes use of them.
19301 Set_Ekind (T, E_Record_Type);
19303 Init_Size_Align (T);
19304 Set_Interfaces (T, No_Elist);
19305 Set_Stored_Constraint (T, No_Elist);
19309 if Ada_Version < Ada_2005
19310 or else not Interface_Present (Def)
19312 if Limited_Present (Def) then
19313 Check_SPARK_Restriction ("limited is not allowed", N);
19316 if Abstract_Present (Def) then
19317 Check_SPARK_Restriction ("abstract is not allowed", N);
19320 -- The flag Is_Tagged_Type might have already been set by
19321 -- Find_Type_Name if it detected an error for declaration T. This
19322 -- arises in the case of private tagged types where the full view
19323 -- omits the word tagged.
19326 Tagged_Present (Def)
19327 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
19329 Set_Is_Tagged_Type (T, Is_Tagged);
19330 Set_Is_Limited_Record (T, Limited_Present (Def));
19332 -- Type is abstract if full declaration carries keyword, or if
19333 -- previous partial view did.
19335 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
19336 or else Abstract_Present (Def));
19339 Check_SPARK_Restriction ("interface is not allowed", N);
19342 Analyze_Interface_Declaration (T, Def);
19344 if Present (Discriminant_Specifications (N)) then
19346 ("interface types cannot have discriminants",
19347 Defining_Identifier
19348 (First (Discriminant_Specifications (N))));
19352 -- First pass: if there are self-referential access components,
19353 -- create the required anonymous access type declarations, and if
19354 -- need be an incomplete type declaration for T itself.
19356 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
19358 if Ada_Version >= Ada_2005
19359 and then Present (Interface_List (Def))
19361 Check_Interfaces (N, Def);
19364 Ifaces_List : Elist_Id;
19367 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
19368 -- already in the parents.
19372 Ifaces_List => Ifaces_List,
19373 Exclude_Parents => True);
19375 Set_Interfaces (T, Ifaces_List);
19379 -- Records constitute a scope for the component declarations within.
19380 -- The scope is created prior to the processing of these declarations.
19381 -- Discriminants are processed first, so that they are visible when
19382 -- processing the other components. The Ekind of the record type itself
19383 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
19385 -- Enter record scope
19389 -- If an incomplete or private type declaration was already given for
19390 -- the type, then this scope already exists, and the discriminants have
19391 -- been declared within. We must verify that the full declaration
19392 -- matches the incomplete one.
19394 Check_Or_Process_Discriminants (N, T, Prev);
19396 Set_Is_Constrained (T, not Has_Discriminants (T));
19397 Set_Has_Delayed_Freeze (T, True);
19399 -- For tagged types add a manually analyzed component corresponding
19400 -- to the component _tag, the corresponding piece of tree will be
19401 -- expanded as part of the freezing actions if it is not a CPP_Class.
19405 -- Do not add the tag unless we are in expansion mode
19407 if Expander_Active then
19408 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
19409 Enter_Name (Tag_Comp);
19411 Set_Ekind (Tag_Comp, E_Component);
19412 Set_Is_Tag (Tag_Comp);
19413 Set_Is_Aliased (Tag_Comp);
19414 Set_Etype (Tag_Comp, RTE (RE_Tag));
19415 Set_DT_Entry_Count (Tag_Comp, No_Uint);
19416 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
19417 Init_Component_Location (Tag_Comp);
19419 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
19420 -- implemented interfaces.
19422 if Has_Interfaces (T) then
19423 Add_Interface_Tag_Components (N, T);
19427 Make_Class_Wide_Type (T);
19428 Set_Direct_Primitive_Operations (T, New_Elmt_List);
19431 -- We must suppress range checks when processing record components in
19432 -- the presence of discriminants, since we don't want spurious checks to
19433 -- be generated during their analysis, but Suppress_Range_Checks flags
19434 -- must be reset the after processing the record definition.
19436 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
19437 -- couldn't we just use the normal range check suppression method here.
19438 -- That would seem cleaner ???
19440 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
19441 Set_Kill_Range_Checks (T, True);
19442 Record_Type_Definition (Def, Prev);
19443 Set_Kill_Range_Checks (T, False);
19445 Record_Type_Definition (Def, Prev);
19448 -- Exit from record scope
19452 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
19453 -- the implemented interfaces and associate them an aliased entity.
19456 and then not Is_Empty_List (Interface_List (Def))
19458 Derive_Progenitor_Subprograms (T, T);
19460 end Record_Type_Declaration;
19462 ----------------------------
19463 -- Record_Type_Definition --
19464 ----------------------------
19466 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
19467 Component : Entity_Id;
19468 Ctrl_Components : Boolean := False;
19469 Final_Storage_Only : Boolean;
19473 if Ekind (Prev_T) = E_Incomplete_Type then
19474 T := Full_View (Prev_T);
19479 -- In SPARK, tagged types and type extensions may only be declared in
19480 -- the specification of library unit packages.
19482 if Present (Def) and then Is_Tagged_Type (T) then
19488 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
19489 Typ := Parent (Def);
19492 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
19493 Typ := Parent (Parent (Def));
19496 Ctxt := Parent (Typ);
19498 if Nkind (Ctxt) = N_Package_Body
19499 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
19501 Check_SPARK_Restriction
19502 ("type should be defined in package specification", Typ);
19504 elsif Nkind (Ctxt) /= N_Package_Specification
19505 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
19507 Check_SPARK_Restriction
19508 ("type should be defined in library unit package", Typ);
19513 Final_Storage_Only := not Is_Controlled (T);
19515 -- Ada 2005: check whether an explicit Limited is present in a derived
19516 -- type declaration.
19518 if Nkind (Parent (Def)) = N_Derived_Type_Definition
19519 and then Limited_Present (Parent (Def))
19521 Set_Is_Limited_Record (T);
19524 -- If the component list of a record type is defined by the reserved
19525 -- word null and there is no discriminant part, then the record type has
19526 -- no components and all records of the type are null records (RM 3.7)
19527 -- This procedure is also called to process the extension part of a
19528 -- record extension, in which case the current scope may have inherited
19532 or else No (Component_List (Def))
19533 or else Null_Present (Component_List (Def))
19535 if not Is_Tagged_Type (T) then
19536 Check_SPARK_Restriction ("non-tagged record cannot be null", Def);
19540 Analyze_Declarations (Component_Items (Component_List (Def)));
19542 if Present (Variant_Part (Component_List (Def))) then
19543 Check_SPARK_Restriction ("variant part is not allowed", Def);
19544 Analyze (Variant_Part (Component_List (Def)));
19548 -- After completing the semantic analysis of the record definition,
19549 -- record components, both new and inherited, are accessible. Set their
19550 -- kind accordingly. Exclude malformed itypes from illegal declarations,
19551 -- whose Ekind may be void.
19553 Component := First_Entity (Current_Scope);
19554 while Present (Component) loop
19555 if Ekind (Component) = E_Void
19556 and then not Is_Itype (Component)
19558 Set_Ekind (Component, E_Component);
19559 Init_Component_Location (Component);
19562 if Has_Task (Etype (Component)) then
19566 if Ekind (Component) /= E_Component then
19569 -- Do not set Has_Controlled_Component on a class-wide equivalent
19570 -- type. See Make_CW_Equivalent_Type.
19572 elsif not Is_Class_Wide_Equivalent_Type (T)
19573 and then (Has_Controlled_Component (Etype (Component))
19574 or else (Chars (Component) /= Name_uParent
19575 and then Is_Controlled (Etype (Component))))
19577 Set_Has_Controlled_Component (T, True);
19578 Final_Storage_Only :=
19580 and then Finalize_Storage_Only (Etype (Component));
19581 Ctrl_Components := True;
19584 Next_Entity (Component);
19587 -- A Type is Finalize_Storage_Only only if all its controlled components
19590 if Ctrl_Components then
19591 Set_Finalize_Storage_Only (T, Final_Storage_Only);
19594 -- Place reference to end record on the proper entity, which may
19595 -- be a partial view.
19597 if Present (Def) then
19598 Process_End_Label (Def, 'e', Prev_T);
19600 end Record_Type_Definition;
19602 ------------------------
19603 -- Replace_Components --
19604 ------------------------
19606 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
19607 function Process (N : Node_Id) return Traverse_Result;
19613 function Process (N : Node_Id) return Traverse_Result is
19617 if Nkind (N) = N_Discriminant_Specification then
19618 Comp := First_Discriminant (Typ);
19619 while Present (Comp) loop
19620 if Chars (Comp) = Chars (Defining_Identifier (N)) then
19621 Set_Defining_Identifier (N, Comp);
19625 Next_Discriminant (Comp);
19628 elsif Nkind (N) = N_Component_Declaration then
19629 Comp := First_Component (Typ);
19630 while Present (Comp) loop
19631 if Chars (Comp) = Chars (Defining_Identifier (N)) then
19632 Set_Defining_Identifier (N, Comp);
19636 Next_Component (Comp);
19643 procedure Replace is new Traverse_Proc (Process);
19645 -- Start of processing for Replace_Components
19649 end Replace_Components;
19651 -------------------------------
19652 -- Set_Completion_Referenced --
19653 -------------------------------
19655 procedure Set_Completion_Referenced (E : Entity_Id) is
19657 -- If in main unit, mark entity that is a completion as referenced,
19658 -- warnings go on the partial view when needed.
19660 if In_Extended_Main_Source_Unit (E) then
19661 Set_Referenced (E);
19663 end Set_Completion_Referenced;
19665 ---------------------
19666 -- Set_Fixed_Range --
19667 ---------------------
19669 -- The range for fixed-point types is complicated by the fact that we
19670 -- do not know the exact end points at the time of the declaration. This
19671 -- is true for three reasons:
19673 -- A size clause may affect the fudging of the end-points.
19674 -- A small clause may affect the values of the end-points.
19675 -- We try to include the end-points if it does not affect the size.
19677 -- This means that the actual end-points must be established at the
19678 -- point when the type is frozen. Meanwhile, we first narrow the range
19679 -- as permitted (so that it will fit if necessary in a small specified
19680 -- size), and then build a range subtree with these narrowed bounds.
19681 -- Set_Fixed_Range constructs the range from real literal values, and
19682 -- sets the range as the Scalar_Range of the given fixed-point type entity.
19684 -- The parent of this range is set to point to the entity so that it is
19685 -- properly hooked into the tree (unlike normal Scalar_Range entries for
19686 -- other scalar types, which are just pointers to the range in the
19687 -- original tree, this would otherwise be an orphan).
19689 -- The tree is left unanalyzed. When the type is frozen, the processing
19690 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
19691 -- analyzed, and uses this as an indication that it should complete
19692 -- work on the range (it will know the final small and size values).
19694 procedure Set_Fixed_Range
19700 S : constant Node_Id :=
19702 Low_Bound => Make_Real_Literal (Loc, Lo),
19703 High_Bound => Make_Real_Literal (Loc, Hi));
19705 Set_Scalar_Range (E, S);
19708 -- Before the freeze point, the bounds of a fixed point are universal
19709 -- and carry the corresponding type.
19711 Set_Etype (Low_Bound (S), Universal_Real);
19712 Set_Etype (High_Bound (S), Universal_Real);
19713 end Set_Fixed_Range;
19715 ----------------------------------
19716 -- Set_Scalar_Range_For_Subtype --
19717 ----------------------------------
19719 procedure Set_Scalar_Range_For_Subtype
19720 (Def_Id : Entity_Id;
19724 Kind : constant Entity_Kind := Ekind (Def_Id);
19727 -- Defend against previous error
19729 if Nkind (R) = N_Error then
19733 Set_Scalar_Range (Def_Id, R);
19735 -- We need to link the range into the tree before resolving it so
19736 -- that types that are referenced, including importantly the subtype
19737 -- itself, are properly frozen (Freeze_Expression requires that the
19738 -- expression be properly linked into the tree). Of course if it is
19739 -- already linked in, then we do not disturb the current link.
19741 if No (Parent (R)) then
19742 Set_Parent (R, Def_Id);
19745 -- Reset the kind of the subtype during analysis of the range, to
19746 -- catch possible premature use in the bounds themselves.
19748 Set_Ekind (Def_Id, E_Void);
19749 Process_Range_Expr_In_Decl (R, Subt);
19750 Set_Ekind (Def_Id, Kind);
19751 end Set_Scalar_Range_For_Subtype;
19753 --------------------------------------------------------
19754 -- Set_Stored_Constraint_From_Discriminant_Constraint --
19755 --------------------------------------------------------
19757 procedure Set_Stored_Constraint_From_Discriminant_Constraint
19761 -- Make sure set if encountered during Expand_To_Stored_Constraint
19763 Set_Stored_Constraint (E, No_Elist);
19765 -- Give it the right value
19767 if Is_Constrained (E) and then Has_Discriminants (E) then
19768 Set_Stored_Constraint (E,
19769 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
19771 end Set_Stored_Constraint_From_Discriminant_Constraint;
19773 -------------------------------------
19774 -- Signed_Integer_Type_Declaration --
19775 -------------------------------------
19777 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
19778 Implicit_Base : Entity_Id;
19779 Base_Typ : Entity_Id;
19782 Errs : Boolean := False;
19786 function Can_Derive_From (E : Entity_Id) return Boolean;
19787 -- Determine whether given bounds allow derivation from specified type
19789 procedure Check_Bound (Expr : Node_Id);
19790 -- Check bound to make sure it is integral and static. If not, post
19791 -- appropriate error message and set Errs flag
19793 ---------------------
19794 -- Can_Derive_From --
19795 ---------------------
19797 -- Note we check both bounds against both end values, to deal with
19798 -- strange types like ones with a range of 0 .. -12341234.
19800 function Can_Derive_From (E : Entity_Id) return Boolean is
19801 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
19802 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
19804 return Lo <= Lo_Val and then Lo_Val <= Hi
19806 Lo <= Hi_Val and then Hi_Val <= Hi;
19807 end Can_Derive_From;
19813 procedure Check_Bound (Expr : Node_Id) is
19815 -- If a range constraint is used as an integer type definition, each
19816 -- bound of the range must be defined by a static expression of some
19817 -- integer type, but the two bounds need not have the same integer
19818 -- type (Negative bounds are allowed.) (RM 3.5.4)
19820 if not Is_Integer_Type (Etype (Expr)) then
19822 ("integer type definition bounds must be of integer type", Expr);
19825 elsif not Is_OK_Static_Expression (Expr) then
19826 Flag_Non_Static_Expr
19827 ("non-static expression used for integer type bound!", Expr);
19830 -- The bounds are folded into literals, and we set their type to be
19831 -- universal, to avoid typing difficulties: we cannot set the type
19832 -- of the literal to the new type, because this would be a forward
19833 -- reference for the back end, and if the original type is user-
19834 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
19837 if Is_Entity_Name (Expr) then
19838 Fold_Uint (Expr, Expr_Value (Expr), True);
19841 Set_Etype (Expr, Universal_Integer);
19845 -- Start of processing for Signed_Integer_Type_Declaration
19848 -- Create an anonymous base type
19851 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
19853 -- Analyze and check the bounds, they can be of any integer type
19855 Lo := Low_Bound (Def);
19856 Hi := High_Bound (Def);
19858 -- Arbitrarily use Integer as the type if either bound had an error
19860 if Hi = Error or else Lo = Error then
19861 Base_Typ := Any_Integer;
19862 Set_Error_Posted (T, True);
19864 -- Here both bounds are OK expressions
19867 Analyze_And_Resolve (Lo, Any_Integer);
19868 Analyze_And_Resolve (Hi, Any_Integer);
19874 Hi := Type_High_Bound (Standard_Long_Long_Integer);
19875 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
19878 -- Find type to derive from
19880 Lo_Val := Expr_Value (Lo);
19881 Hi_Val := Expr_Value (Hi);
19883 if Can_Derive_From (Standard_Short_Short_Integer) then
19884 Base_Typ := Base_Type (Standard_Short_Short_Integer);
19886 elsif Can_Derive_From (Standard_Short_Integer) then
19887 Base_Typ := Base_Type (Standard_Short_Integer);
19889 elsif Can_Derive_From (Standard_Integer) then
19890 Base_Typ := Base_Type (Standard_Integer);
19892 elsif Can_Derive_From (Standard_Long_Integer) then
19893 Base_Typ := Base_Type (Standard_Long_Integer);
19895 elsif Can_Derive_From (Standard_Long_Long_Integer) then
19896 Base_Typ := Base_Type (Standard_Long_Long_Integer);
19899 Base_Typ := Base_Type (Standard_Long_Long_Integer);
19900 Error_Msg_N ("integer type definition bounds out of range", Def);
19901 Hi := Type_High_Bound (Standard_Long_Long_Integer);
19902 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
19906 -- Complete both implicit base and declared first subtype entities
19908 Set_Etype (Implicit_Base, Base_Typ);
19909 Set_Size_Info (Implicit_Base, (Base_Typ));
19910 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
19911 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
19913 Set_Ekind (T, E_Signed_Integer_Subtype);
19914 Set_Etype (T, Implicit_Base);
19916 -- In formal verification mode, restrict the base type's range to the
19917 -- minimum allowed by RM 3.5.4, namely the smallest symmetric range
19918 -- around zero with a possible extra negative value that contains the
19919 -- subtype range. Keep Size, RM_Size and First_Rep_Item info, which
19920 -- should not be relied upon in formal verification.
19922 if Strict_Alfa_Mode then
19926 Dloc : constant Source_Ptr := Sloc (Def);
19932 -- If the subtype range is empty, the smallest base type range
19933 -- is the symmetric range around zero containing Lo_Val and
19936 if UI_Gt (Lo_Val, Hi_Val) then
19937 Sym_Hi_Val := UI_Max (UI_Abs (Lo_Val), UI_Abs (Hi_Val));
19938 Sym_Lo_Val := UI_Negate (Sym_Hi_Val);
19940 -- Otherwise, if the subtype range is not empty and Hi_Val has
19941 -- the largest absolute value, Hi_Val is non negative and the
19942 -- smallest base type range is the symmetric range around zero
19943 -- containing Hi_Val.
19945 elsif UI_Le (UI_Abs (Lo_Val), UI_Abs (Hi_Val)) then
19946 Sym_Hi_Val := Hi_Val;
19947 Sym_Lo_Val := UI_Negate (Hi_Val);
19949 -- Otherwise, the subtype range is not empty, Lo_Val has the
19950 -- strictly largest absolute value, Lo_Val is negative and the
19951 -- smallest base type range is the symmetric range around zero
19952 -- with an extra negative value Lo_Val.
19955 Sym_Lo_Val := Lo_Val;
19956 Sym_Hi_Val := UI_Sub (UI_Negate (Lo_Val), Uint_1);
19959 Lbound := Make_Integer_Literal (Dloc, Sym_Lo_Val);
19960 Ubound := Make_Integer_Literal (Dloc, Sym_Hi_Val);
19961 Set_Is_Static_Expression (Lbound);
19962 Set_Is_Static_Expression (Ubound);
19963 Analyze_And_Resolve (Lbound, Any_Integer);
19964 Analyze_And_Resolve (Ubound, Any_Integer);
19966 Bounds := Make_Range (Dloc, Lbound, Ubound);
19967 Set_Etype (Bounds, Base_Typ);
19969 Set_Scalar_Range (Implicit_Base, Bounds);
19973 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
19976 Set_Size_Info (T, (Implicit_Base));
19977 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
19978 Set_Scalar_Range (T, Def);
19979 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
19980 Set_Is_Constrained (T);
19981 end Signed_Integer_Type_Declaration;