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_Disp; use Sem_Disp;
60 with Sem_Dist; use Sem_Dist;
61 with Sem_Elim; use Sem_Elim;
62 with Sem_Eval; use Sem_Eval;
63 with Sem_Mech; use Sem_Mech;
64 with Sem_Prag; use Sem_Prag;
65 with Sem_Res; use Sem_Res;
66 with Sem_Smem; use Sem_Smem;
67 with Sem_Type; use Sem_Type;
68 with Sem_Util; use Sem_Util;
69 with Sem_Warn; use Sem_Warn;
70 with Stand; use Stand;
71 with Sinfo; use Sinfo;
72 with Sinput; use Sinput;
73 with Snames; use Snames;
74 with Targparm; use Targparm;
75 with Tbuild; use Tbuild;
76 with Ttypes; use Ttypes;
77 with Uintp; use Uintp;
78 with Urealp; use Urealp;
80 package body Sem_Ch3 is
82 -----------------------
83 -- Local Subprograms --
84 -----------------------
86 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
87 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
88 -- abstract interface types implemented by a record type or a derived
91 procedure Build_Derived_Type
93 Parent_Type : Entity_Id;
94 Derived_Type : Entity_Id;
95 Is_Completion : Boolean;
96 Derive_Subps : Boolean := True);
97 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
98 -- the N_Full_Type_Declaration node containing the derived type definition.
99 -- Parent_Type is the entity for the parent type in the derived type
100 -- definition and Derived_Type the actual derived type. Is_Completion must
101 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
102 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
103 -- completion of a private type declaration. If Is_Completion is set to
104 -- True, N is the completion of a private type declaration and Derived_Type
105 -- is different from the defining identifier inside N (i.e. Derived_Type /=
106 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
107 -- subprograms should be derived. The only case where this parameter is
108 -- False is when Build_Derived_Type is recursively called to process an
109 -- implicit derived full type for a type derived from a private type (in
110 -- that case the subprograms must only be derived for the private view of
113 -- ??? These flags need a bit of re-examination and re-documentation:
114 -- ??? are they both necessary (both seem related to the recursion)?
116 procedure Build_Derived_Access_Type
118 Parent_Type : Entity_Id;
119 Derived_Type : Entity_Id);
120 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
121 -- create an implicit base if the parent type is constrained or if the
122 -- subtype indication has a constraint.
124 procedure Build_Derived_Array_Type
126 Parent_Type : Entity_Id;
127 Derived_Type : Entity_Id);
128 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
129 -- create an implicit base if the parent type is constrained or if the
130 -- subtype indication has a constraint.
132 procedure Build_Derived_Concurrent_Type
134 Parent_Type : Entity_Id;
135 Derived_Type : Entity_Id);
136 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
137 -- protected type, inherit entries and protected subprograms, check
138 -- legality of discriminant constraints if any.
140 procedure Build_Derived_Enumeration_Type
142 Parent_Type : Entity_Id;
143 Derived_Type : Entity_Id);
144 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
145 -- type, we must create a new list of literals. Types derived from
146 -- Character and [Wide_]Wide_Character are special-cased.
148 procedure Build_Derived_Numeric_Type
150 Parent_Type : Entity_Id;
151 Derived_Type : Entity_Id);
152 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
153 -- an anonymous base type, and propagate constraint to subtype if needed.
155 procedure Build_Derived_Private_Type
157 Parent_Type : Entity_Id;
158 Derived_Type : Entity_Id;
159 Is_Completion : Boolean;
160 Derive_Subps : Boolean := True);
161 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
162 -- because the parent may or may not have a completion, and the derivation
163 -- may itself be a completion.
165 procedure Build_Derived_Record_Type
167 Parent_Type : Entity_Id;
168 Derived_Type : Entity_Id;
169 Derive_Subps : Boolean := True);
170 -- Subsidiary procedure for Build_Derived_Type and
171 -- Analyze_Private_Extension_Declaration used for tagged and untagged
172 -- record types. All parameters are as in Build_Derived_Type except that
173 -- N, in addition to being an N_Full_Type_Declaration node, can also be an
174 -- N_Private_Extension_Declaration node. See the definition of this routine
175 -- for much more info. Derive_Subps indicates whether subprograms should
176 -- be derived from the parent type. The only case where Derive_Subps is
177 -- False is for an implicit derived full type for a type derived from a
178 -- private type (see Build_Derived_Type).
180 procedure Build_Discriminal (Discrim : Entity_Id);
181 -- Create the discriminal corresponding to discriminant Discrim, that is
182 -- the parameter corresponding to Discrim to be used in initialization
183 -- procedures for the type where Discrim is a discriminant. Discriminals
184 -- are not used during semantic analysis, and are not fully defined
185 -- entities until expansion. Thus they are not given a scope until
186 -- initialization procedures are built.
188 function Build_Discriminant_Constraints
191 Derived_Def : Boolean := False) return Elist_Id;
192 -- Validate discriminant constraints and return the list of the constraints
193 -- in order of discriminant declarations, where T is the discriminated
194 -- unconstrained type. Def is the N_Subtype_Indication node where the
195 -- discriminants constraints for T are specified. Derived_Def is True
196 -- when building the discriminant constraints in a derived type definition
197 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
198 -- type and Def is the constraint "(xxx)" on T and this routine sets the
199 -- Corresponding_Discriminant field of the discriminants in the derived
200 -- type D to point to the corresponding discriminants in the parent type T.
202 procedure Build_Discriminated_Subtype
206 Related_Nod : Node_Id;
207 For_Access : Boolean := False);
208 -- Subsidiary procedure to Constrain_Discriminated_Type and to
209 -- Process_Incomplete_Dependents. Given
211 -- T (a possibly discriminated base type)
212 -- Def_Id (a very partially built subtype for T),
214 -- the call completes Def_Id to be the appropriate E_*_Subtype.
216 -- The Elist is the list of discriminant constraints if any (it is set
217 -- to No_Elist if T is not a discriminated type, and to an empty list if
218 -- T has discriminants but there are no discriminant constraints). The
219 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
220 -- The For_Access says whether or not this subtype is really constraining
221 -- an access type. That is its sole purpose is the designated type of an
222 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
223 -- is built to avoid freezing T when the access subtype is frozen.
225 function Build_Scalar_Bound
228 Der_T : Entity_Id) return Node_Id;
229 -- The bounds of a derived scalar type are conversions of the bounds of
230 -- the parent type. Optimize the representation if the bounds are literals.
231 -- Needs a more complete spec--what are the parameters exactly, and what
232 -- exactly is the returned value, and how is Bound affected???
234 procedure Build_Underlying_Full_View
238 -- If the completion of a private type is itself derived from a private
239 -- type, or if the full view of a private subtype is itself private, the
240 -- back-end has no way to compute the actual size of this type. We build
241 -- an internal subtype declaration of the proper parent type to convey
242 -- this information. This extra mechanism is needed because a full
243 -- view cannot itself have a full view (it would get clobbered during
246 procedure Check_Access_Discriminant_Requires_Limited
249 -- Check the restriction that the type to which an access discriminant
250 -- belongs must be a concurrent type or a descendant of a type with
251 -- the reserved word 'limited' in its declaration.
253 procedure Check_Anonymous_Access_Components
257 Comp_List : Node_Id);
258 -- Ada 2005 AI-382: an access component in a record definition can refer to
259 -- the enclosing record, in which case it denotes the type itself, and not
260 -- the current instance of the type. We create an anonymous access type for
261 -- the component, and flag it as an access to a component, so accessibility
262 -- checks are properly performed on it. The declaration of the access type
263 -- is placed ahead of that of the record to prevent order-of-elaboration
264 -- circularity issues in Gigi. We create an incomplete type for the record
265 -- declaration, which is the designated type of the anonymous access.
267 procedure Check_Delta_Expression (E : Node_Id);
268 -- Check that the expression represented by E is suitable for use as a
269 -- delta expression, i.e. it is of real type and is static.
271 procedure Check_Digits_Expression (E : Node_Id);
272 -- Check that the expression represented by E is suitable for use as a
273 -- digits expression, i.e. it is of integer type, positive and static.
275 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
276 -- Validate the initialization of an object declaration. T is the required
277 -- type, and Exp is the initialization expression.
279 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
280 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
282 procedure Check_Or_Process_Discriminants
285 Prev : Entity_Id := Empty);
286 -- If N is the full declaration of the completion T of an incomplete or
287 -- private type, check its discriminants (which are already known to be
288 -- conformant with those of the partial view, see Find_Type_Name),
289 -- otherwise process them. Prev is the entity of the partial declaration,
292 procedure Check_Real_Bound (Bound : Node_Id);
293 -- Check given bound for being of real type and static. If not, post an
294 -- appropriate message, and rewrite the bound with the real literal zero.
296 procedure Constant_Redeclaration
300 -- Various checks on legality of full declaration of deferred constant.
301 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
302 -- node. The caller has not yet set any attributes of this entity.
304 function Contain_Interface
306 Ifaces : Elist_Id) return Boolean;
307 -- Ada 2005: Determine whether Iface is present in the list Ifaces
309 procedure Convert_Scalar_Bounds
311 Parent_Type : Entity_Id;
312 Derived_Type : Entity_Id;
314 -- For derived scalar types, convert the bounds in the type definition to
315 -- the derived type, and complete their analysis. Given a constraint of the
316 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
317 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
318 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
319 -- subtype are conversions of those bounds to the derived_type, so that
320 -- their typing is consistent.
322 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
323 -- Copies attributes from array base type T2 to array base type T1. Copies
324 -- only attributes that apply to base types, but not subtypes.
326 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
327 -- Copies attributes from array subtype T2 to array subtype T1. Copies
328 -- attributes that apply to both subtypes and base types.
330 procedure Create_Constrained_Components
334 Constraints : Elist_Id);
335 -- Build the list of entities for a constrained discriminated record
336 -- subtype. If a component depends on a discriminant, replace its subtype
337 -- using the discriminant values in the discriminant constraint. Subt
338 -- is the defining identifier for the subtype whose list of constrained
339 -- entities we will create. Decl_Node is the type declaration node where
340 -- we will attach all the itypes created. Typ is the base discriminated
341 -- type for the subtype Subt. Constraints is the list of discriminant
342 -- constraints for Typ.
344 function Constrain_Component_Type
346 Constrained_Typ : Entity_Id;
347 Related_Node : Node_Id;
349 Constraints : Elist_Id) return Entity_Id;
350 -- Given a discriminated base type Typ, a list of discriminant constraint
351 -- Constraints for Typ and a component of Typ, with type Compon_Type,
352 -- create and return the type corresponding to Compon_type where all
353 -- discriminant references are replaced with the corresponding constraint.
354 -- If no discriminant references occur in Compon_Typ then return it as is.
355 -- Constrained_Typ is the final constrained subtype to which the
356 -- constrained Compon_Type belongs. Related_Node is the node where we will
357 -- attach all the itypes created.
359 -- Above description is confused, what is Compon_Type???
361 procedure Constrain_Access
362 (Def_Id : in out Entity_Id;
364 Related_Nod : Node_Id);
365 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
366 -- an anonymous type created for a subtype indication. In that case it is
367 -- created in the procedure and attached to Related_Nod.
369 procedure Constrain_Array
370 (Def_Id : in out Entity_Id;
372 Related_Nod : Node_Id;
373 Related_Id : Entity_Id;
375 -- Apply a list of index constraints to an unconstrained array type. The
376 -- first parameter is the entity for the resulting subtype. A value of
377 -- Empty for Def_Id indicates that an implicit type must be created, but
378 -- creation is delayed (and must be done by this procedure) because other
379 -- subsidiary implicit types must be created first (which is why Def_Id
380 -- is an in/out parameter). The second parameter is a subtype indication
381 -- node for the constrained array to be created (e.g. something of the
382 -- form string (1 .. 10)). Related_Nod gives the place where this type
383 -- has to be inserted in the tree. The Related_Id and Suffix parameters
384 -- are used to build the associated Implicit type name.
386 procedure Constrain_Concurrent
387 (Def_Id : in out Entity_Id;
389 Related_Nod : Node_Id;
390 Related_Id : Entity_Id;
392 -- Apply list of discriminant constraints to an unconstrained concurrent
395 -- SI is the N_Subtype_Indication node containing the constraint and
396 -- the unconstrained type to constrain.
398 -- Def_Id is the entity for the resulting constrained subtype. A value
399 -- of Empty for Def_Id indicates that an implicit type must be created,
400 -- but creation is delayed (and must be done by this procedure) because
401 -- other subsidiary implicit types must be created first (which is why
402 -- Def_Id is an in/out parameter).
404 -- Related_Nod gives the place where this type has to be inserted
407 -- The last two arguments are used to create its external name if needed.
409 function Constrain_Corresponding_Record
410 (Prot_Subt : Entity_Id;
411 Corr_Rec : Entity_Id;
412 Related_Nod : Node_Id;
413 Related_Id : Entity_Id) return Entity_Id;
414 -- When constraining a protected type or task type with discriminants,
415 -- constrain the corresponding record with the same discriminant values.
417 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
418 -- Constrain a decimal fixed point type with a digits constraint and/or a
419 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
421 procedure Constrain_Discriminated_Type
424 Related_Nod : Node_Id;
425 For_Access : Boolean := False);
426 -- Process discriminant constraints of composite type. Verify that values
427 -- have been provided for all discriminants, that the original type is
428 -- unconstrained, and that the types of the supplied expressions match
429 -- the discriminant types. The first three parameters are like in routine
430 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
433 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
434 -- Constrain an enumeration type with a range constraint. This is identical
435 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
437 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
438 -- Constrain a floating point type with either a digits constraint
439 -- and/or a range constraint, building a E_Floating_Point_Subtype.
441 procedure Constrain_Index
444 Related_Nod : Node_Id;
445 Related_Id : Entity_Id;
448 -- Process an index constraint S in a constrained array declaration. The
449 -- constraint can be a subtype name, or a range with or without an explicit
450 -- subtype mark. The index is the corresponding index of the unconstrained
451 -- array. The Related_Id and Suffix parameters are used to build the
452 -- associated Implicit type name.
454 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
455 -- Build subtype of a signed or modular integer type
457 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
458 -- Constrain an ordinary fixed point type with a range constraint, and
459 -- build an E_Ordinary_Fixed_Point_Subtype entity.
461 procedure Copy_And_Swap (Priv, Full : Entity_Id);
462 -- Copy the Priv entity into the entity of its full declaration then swap
463 -- the two entities in such a manner that the former private type is now
464 -- seen as a full type.
466 procedure Decimal_Fixed_Point_Type_Declaration
469 -- Create a new decimal fixed point type, and apply the constraint to
470 -- obtain a subtype of this new type.
472 procedure Complete_Private_Subtype
475 Full_Base : Entity_Id;
476 Related_Nod : Node_Id);
477 -- Complete the implicit full view of a private subtype by setting the
478 -- appropriate semantic fields. If the full view of the parent is a record
479 -- type, build constrained components of subtype.
481 procedure Derive_Progenitor_Subprograms
482 (Parent_Type : Entity_Id;
483 Tagged_Type : Entity_Id);
484 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
485 -- operations of progenitors of Tagged_Type, and replace the subsidiary
486 -- subtypes with Tagged_Type, to build the specs of the inherited interface
487 -- primitives. The derived primitives are aliased to those of the
488 -- interface. This routine takes care also of transferring to the full view
489 -- subprograms associated with the partial view of Tagged_Type that cover
490 -- interface primitives.
492 procedure Derived_Standard_Character
494 Parent_Type : Entity_Id;
495 Derived_Type : Entity_Id);
496 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
497 -- derivations from types Standard.Character and Standard.Wide_Character.
499 procedure Derived_Type_Declaration
502 Is_Completion : Boolean);
503 -- Process a derived type declaration. Build_Derived_Type is invoked
504 -- to process the actual derived type definition. Parameters N and
505 -- Is_Completion have the same meaning as in Build_Derived_Type.
506 -- T is the N_Defining_Identifier for the entity defined in the
507 -- N_Full_Type_Declaration node N, that is T is the derived type.
509 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
510 -- Insert each literal in symbol table, as an overloadable identifier. Each
511 -- enumeration type is mapped into a sequence of integers, and each literal
512 -- is defined as a constant with integer value. If any of the literals are
513 -- character literals, the type is a character type, which means that
514 -- strings are legal aggregates for arrays of components of the type.
516 function Expand_To_Stored_Constraint
518 Constraint : Elist_Id) return Elist_Id;
519 -- Given a constraint (i.e. a list of expressions) on the discriminants of
520 -- Typ, expand it into a constraint on the stored discriminants and return
521 -- the new list of expressions constraining the stored discriminants.
523 function Find_Type_Of_Object
525 Related_Nod : Node_Id) return Entity_Id;
526 -- Get type entity for object referenced by Obj_Def, attaching the
527 -- implicit types generated to Related_Nod
529 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
530 -- Create a new float and apply the constraint to obtain subtype of it
532 function Has_Range_Constraint (N : Node_Id) return Boolean;
533 -- Given an N_Subtype_Indication node N, return True if a range constraint
534 -- is present, either directly, or as part of a digits or delta constraint.
535 -- In addition, a digits constraint in the decimal case returns True, since
536 -- it establishes a default range if no explicit range is present.
538 function Inherit_Components
540 Parent_Base : Entity_Id;
541 Derived_Base : Entity_Id;
543 Inherit_Discr : Boolean;
544 Discs : Elist_Id) return Elist_Id;
545 -- Called from Build_Derived_Record_Type to inherit the components of
546 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
547 -- For more information on derived types and component inheritance please
548 -- consult the comment above the body of Build_Derived_Record_Type.
550 -- N is the original derived type declaration
552 -- Is_Tagged is set if we are dealing with tagged types
554 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
555 -- Parent_Base, otherwise no discriminants are inherited.
557 -- Discs gives the list of constraints that apply to Parent_Base in the
558 -- derived type declaration. If Discs is set to No_Elist, then we have
559 -- the following situation:
561 -- type Parent (D1..Dn : ..) is [tagged] record ...;
562 -- type Derived is new Parent [with ...];
564 -- which gets treated as
566 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
568 -- For untagged types the returned value is an association list. The list
569 -- starts from the association (Parent_Base => Derived_Base), and then it
570 -- contains a sequence of the associations of the form
572 -- (Old_Component => New_Component),
574 -- where Old_Component is the Entity_Id of a component in Parent_Base and
575 -- New_Component is the Entity_Id of the corresponding component in
576 -- Derived_Base. For untagged records, this association list is needed when
577 -- copying the record declaration for the derived base. In the tagged case
578 -- the value returned is irrelevant.
580 function Is_Valid_Constraint_Kind
582 Constraint_Kind : Node_Kind) return Boolean;
583 -- Returns True if it is legal to apply the given kind of constraint to the
584 -- given kind of type (index constraint to an array type, for example).
586 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
587 -- Create new modular type. Verify that modulus is in bounds
589 procedure New_Concatenation_Op (Typ : Entity_Id);
590 -- Create an abbreviated declaration for an operator in order to
591 -- materialize concatenation on array types.
593 procedure Ordinary_Fixed_Point_Type_Declaration
596 -- Create a new ordinary fixed point type, and apply the constraint to
597 -- obtain subtype of it.
599 procedure Prepare_Private_Subtype_Completion
601 Related_Nod : Node_Id);
602 -- Id is a subtype of some private type. Creates the full declaration
603 -- associated with Id whenever possible, i.e. when the full declaration
604 -- of the base type is already known. Records each subtype into
605 -- Private_Dependents of the base type.
607 procedure Process_Incomplete_Dependents
611 -- Process all entities that depend on an incomplete type. There include
612 -- subtypes, subprogram types that mention the incomplete type in their
613 -- profiles, and subprogram with access parameters that designate the
616 -- Inc_T is the defining identifier of an incomplete type declaration, its
617 -- Ekind is E_Incomplete_Type.
619 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
621 -- Full_T is N's defining identifier.
623 -- Subtypes of incomplete types with discriminants are completed when the
624 -- parent type is. This is simpler than private subtypes, because they can
625 -- only appear in the same scope, and there is no need to exchange views.
626 -- Similarly, access_to_subprogram types may have a parameter or a return
627 -- type that is an incomplete type, and that must be replaced with the
630 -- If the full type is tagged, subprogram with access parameters that
631 -- designated the incomplete may be primitive operations of the full type,
632 -- and have to be processed accordingly.
634 procedure Process_Real_Range_Specification (Def : Node_Id);
635 -- Given the type definition for a real type, this procedure processes and
636 -- checks the real range specification of this type definition if one is
637 -- present. If errors are found, error messages are posted, and the
638 -- Real_Range_Specification of Def is reset to Empty.
640 procedure Record_Type_Declaration
644 -- Process a record type declaration (for both untagged and tagged
645 -- records). Parameters T and N are exactly like in procedure
646 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
647 -- for this routine. If this is the completion of an incomplete type
648 -- declaration, Prev is the entity of the incomplete declaration, used for
649 -- cross-referencing. Otherwise Prev = T.
651 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
652 -- This routine is used to process the actual record type definition (both
653 -- for untagged and tagged records). Def is a record type definition node.
654 -- This procedure analyzes the components in this record type definition.
655 -- Prev_T is the entity for the enclosing record type. It is provided so
656 -- that its Has_Task flag can be set if any of the component have Has_Task
657 -- set. If the declaration is the completion of an incomplete type
658 -- declaration, Prev_T is the original incomplete type, whose full view is
661 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
662 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
663 -- build a copy of the declaration tree of the parent, and we create
664 -- independently the list of components for the derived type. Semantic
665 -- information uses the component entities, but record representation
666 -- clauses are validated on the declaration tree. This procedure replaces
667 -- discriminants and components in the declaration with those that have
668 -- been created by Inherit_Components.
670 procedure Set_Fixed_Range
675 -- Build a range node with the given bounds and set it as the Scalar_Range
676 -- of the given fixed-point type entity. Loc is the source location used
677 -- for the constructed range. See body for further details.
679 procedure Set_Scalar_Range_For_Subtype
683 -- This routine is used to set the scalar range field for a subtype given
684 -- Def_Id, the entity for the subtype, and R, the range expression for the
685 -- scalar range. Subt provides the parent subtype to be used to analyze,
686 -- resolve, and check the given range.
688 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
689 -- Create a new signed integer entity, and apply the constraint to obtain
690 -- the required first named subtype of this type.
692 procedure Set_Stored_Constraint_From_Discriminant_Constraint
694 -- E is some record type. This routine computes E's Stored_Constraint
695 -- from its Discriminant_Constraint.
697 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
698 -- Check that an entity in a list of progenitors is an interface,
699 -- emit error otherwise.
701 -----------------------
702 -- Access_Definition --
703 -----------------------
705 function Access_Definition
706 (Related_Nod : Node_Id;
707 N : Node_Id) return Entity_Id
709 Anon_Type : Entity_Id;
710 Anon_Scope : Entity_Id;
711 Desig_Type : Entity_Id;
712 Enclosing_Prot_Type : Entity_Id := Empty;
715 Check_SPARK_Restriction ("access type is not allowed", N);
717 if Is_Entry (Current_Scope)
718 and then Is_Task_Type (Etype (Scope (Current_Scope)))
720 Error_Msg_N ("task entries cannot have access parameters", N);
724 -- Ada 2005: for an object declaration the corresponding anonymous
725 -- type is declared in the current scope.
727 -- If the access definition is the return type of another access to
728 -- function, scope is the current one, because it is the one of the
729 -- current type declaration, except for the pathological case below.
731 if Nkind_In (Related_Nod, N_Object_Declaration,
732 N_Access_Function_Definition)
734 Anon_Scope := Current_Scope;
736 -- A pathological case: function returning access functions that
737 -- return access functions, etc. Each anonymous access type created
738 -- is in the enclosing scope of the outermost function.
745 while Nkind_In (Par, N_Access_Function_Definition,
751 if Nkind (Par) = N_Function_Specification then
752 Anon_Scope := Scope (Defining_Entity (Par));
756 -- For the anonymous function result case, retrieve the scope of the
757 -- function specification's associated entity rather than using the
758 -- current scope. The current scope will be the function itself if the
759 -- formal part is currently being analyzed, but will be the parent scope
760 -- in the case of a parameterless function, and we always want to use
761 -- the function's parent scope. Finally, if the function is a child
762 -- unit, we must traverse the tree to retrieve the proper entity.
764 elsif Nkind (Related_Nod) = N_Function_Specification
765 and then Nkind (Parent (N)) /= N_Parameter_Specification
767 -- If the current scope is a protected type, the anonymous access
768 -- is associated with one of the protected operations, and must
769 -- be available in the scope that encloses the protected declaration.
770 -- Otherwise the type is in the scope enclosing the subprogram.
772 -- If the function has formals, The return type of a subprogram
773 -- declaration is analyzed in the scope of the subprogram (see
774 -- Process_Formals) and thus the protected type, if present, is
775 -- the scope of the current function scope.
777 if Ekind (Current_Scope) = E_Protected_Type then
778 Enclosing_Prot_Type := Current_Scope;
780 elsif Ekind (Current_Scope) = E_Function
781 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
783 Enclosing_Prot_Type := Scope (Current_Scope);
786 if Present (Enclosing_Prot_Type) then
787 Anon_Scope := Scope (Enclosing_Prot_Type);
790 Anon_Scope := Scope (Defining_Entity (Related_Nod));
793 -- For an access type definition, if the current scope is a child
794 -- unit it is the scope of the type.
796 elsif Is_Compilation_Unit (Current_Scope) then
797 Anon_Scope := Current_Scope;
799 -- For access formals, access components, and access discriminants, the
800 -- scope is that of the enclosing declaration,
803 Anon_Scope := Scope (Current_Scope);
808 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
811 and then Ada_Version >= Ada_2005
813 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
816 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
817 -- the corresponding semantic routine
819 if Present (Access_To_Subprogram_Definition (N)) then
821 -- Compiler runtime units are compiled in Ada 2005 mode when building
822 -- the runtime library but must also be compilable in Ada 95 mode
823 -- (when bootstrapping the compiler).
825 Check_Compiler_Unit (N);
827 Access_Subprogram_Declaration
828 (T_Name => Anon_Type,
829 T_Def => Access_To_Subprogram_Definition (N));
831 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
833 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
836 (Anon_Type, E_Anonymous_Access_Subprogram_Type);
839 Set_Can_Use_Internal_Rep
840 (Anon_Type, not Always_Compatible_Rep_On_Target);
842 -- If the anonymous access is associated with a protected operation,
843 -- create a reference to it after the enclosing protected definition
844 -- because the itype will be used in the subsequent bodies.
846 if Ekind (Current_Scope) = E_Protected_Type then
847 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
853 Find_Type (Subtype_Mark (N));
854 Desig_Type := Entity (Subtype_Mark (N));
856 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
857 Set_Etype (Anon_Type, Anon_Type);
859 -- Make sure the anonymous access type has size and alignment fields
860 -- set, as required by gigi. This is necessary in the case of the
861 -- Task_Body_Procedure.
863 if not Has_Private_Component (Desig_Type) then
864 Layout_Type (Anon_Type);
867 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
868 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
869 -- the null value is allowed. In Ada 95 the null value is never allowed.
871 if Ada_Version >= Ada_2005 then
872 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
874 Set_Can_Never_Be_Null (Anon_Type, True);
877 -- The anonymous access type is as public as the discriminated type or
878 -- subprogram that defines it. It is imported (for back-end purposes)
879 -- if the designated type is.
881 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
883 -- Ada 2005 (AI-231): Propagate the access-constant attribute
885 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
887 -- The context is either a subprogram declaration, object declaration,
888 -- or an access discriminant, in a private or a full type declaration.
889 -- In the case of a subprogram, if the designated type is incomplete,
890 -- the operation will be a primitive operation of the full type, to be
891 -- updated subsequently. If the type is imported through a limited_with
892 -- clause, the subprogram is not a primitive operation of the type
893 -- (which is declared elsewhere in some other scope).
895 if Ekind (Desig_Type) = E_Incomplete_Type
896 and then not From_With_Type (Desig_Type)
897 and then Is_Overloadable (Current_Scope)
899 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
900 Set_Has_Delayed_Freeze (Current_Scope);
903 -- Ada 2005: if the designated type is an interface that may contain
904 -- tasks, create a Master entity for the declaration. This must be done
905 -- before expansion of the full declaration, because the declaration may
906 -- include an expression that is an allocator, whose expansion needs the
907 -- proper Master for the created tasks.
909 if Nkind (Related_Nod) = N_Object_Declaration
910 and then Expander_Active
912 if Is_Interface (Desig_Type)
913 and then Is_Limited_Record (Desig_Type)
915 Build_Class_Wide_Master (Anon_Type);
917 -- Similarly, if the type is an anonymous access that designates
918 -- tasks, create a master entity for it in the current context.
920 elsif Has_Task (Desig_Type)
921 and then Comes_From_Source (Related_Nod)
923 Build_Master_Entity (Defining_Identifier (Related_Nod));
924 Build_Master_Renaming (Anon_Type);
928 -- For a private component of a protected type, it is imperative that
929 -- the back-end elaborate the type immediately after the protected
930 -- declaration, because this type will be used in the declarations
931 -- created for the component within each protected body, so we must
932 -- create an itype reference for it now.
934 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
935 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
937 -- Similarly, if the access definition is the return result of a
938 -- function, create an itype reference for it because it will be used
939 -- within the function body. For a regular function that is not a
940 -- compilation unit, insert reference after the declaration. For a
941 -- protected operation, insert it after the enclosing protected type
942 -- declaration. In either case, do not create a reference for a type
943 -- obtained through a limited_with clause, because this would introduce
944 -- semantic dependencies.
946 -- Similarly, do not create a reference if the designated type is a
947 -- generic formal, because no use of it will reach the backend.
949 elsif Nkind (Related_Nod) = N_Function_Specification
950 and then not From_With_Type (Desig_Type)
951 and then not Is_Generic_Type (Desig_Type)
953 if Present (Enclosing_Prot_Type) then
954 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
956 elsif Is_List_Member (Parent (Related_Nod))
957 and then Nkind (Parent (N)) /= N_Parameter_Specification
959 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
962 -- Finally, create an itype reference for an object declaration of an
963 -- anonymous access type. This is strictly necessary only for deferred
964 -- constants, but in any case will avoid out-of-scope problems in the
967 elsif Nkind (Related_Nod) = N_Object_Declaration then
968 Build_Itype_Reference (Anon_Type, Related_Nod);
972 end Access_Definition;
974 -----------------------------------
975 -- Access_Subprogram_Declaration --
976 -----------------------------------
978 procedure Access_Subprogram_Declaration
983 procedure Check_For_Premature_Usage (Def : Node_Id);
984 -- Check that type T_Name is not used, directly or recursively, as a
985 -- parameter or a return type in Def. Def is either a subtype, an
986 -- access_definition, or an access_to_subprogram_definition.
988 -------------------------------
989 -- Check_For_Premature_Usage --
990 -------------------------------
992 procedure Check_For_Premature_Usage (Def : Node_Id) is
996 -- Check for a subtype mark
998 if Nkind (Def) in N_Has_Etype then
999 if Etype (Def) = T_Name then
1001 ("type& cannot be used before end of its declaration", Def);
1004 -- If this is not a subtype, then this is an access_definition
1006 elsif Nkind (Def) = N_Access_Definition then
1007 if Present (Access_To_Subprogram_Definition (Def)) then
1008 Check_For_Premature_Usage
1009 (Access_To_Subprogram_Definition (Def));
1011 Check_For_Premature_Usage (Subtype_Mark (Def));
1014 -- The only cases left are N_Access_Function_Definition and
1015 -- N_Access_Procedure_Definition.
1018 if Present (Parameter_Specifications (Def)) then
1019 Param := First (Parameter_Specifications (Def));
1020 while Present (Param) loop
1021 Check_For_Premature_Usage (Parameter_Type (Param));
1022 Param := Next (Param);
1026 if Nkind (Def) = N_Access_Function_Definition then
1027 Check_For_Premature_Usage (Result_Definition (Def));
1030 end Check_For_Premature_Usage;
1034 Formals : constant List_Id := Parameter_Specifications (T_Def);
1037 Desig_Type : constant Entity_Id :=
1038 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1040 -- Start of processing for Access_Subprogram_Declaration
1043 Check_SPARK_Restriction ("access type is not allowed", T_Def);
1045 -- Associate the Itype node with the inner full-type declaration or
1046 -- subprogram spec or entry body. This is required to handle nested
1047 -- anonymous declarations. For example:
1050 -- (X : access procedure
1051 -- (Y : access procedure
1054 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1055 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1056 N_Private_Type_Declaration,
1057 N_Private_Extension_Declaration,
1058 N_Procedure_Specification,
1059 N_Function_Specification,
1063 Nkind_In (D_Ityp, N_Object_Declaration,
1064 N_Object_Renaming_Declaration,
1065 N_Formal_Object_Declaration,
1066 N_Formal_Type_Declaration,
1067 N_Task_Type_Declaration,
1068 N_Protected_Type_Declaration))
1070 D_Ityp := Parent (D_Ityp);
1071 pragma Assert (D_Ityp /= Empty);
1074 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1076 if Nkind_In (D_Ityp, N_Procedure_Specification,
1077 N_Function_Specification)
1079 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1081 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1082 N_Object_Declaration,
1083 N_Object_Renaming_Declaration,
1084 N_Formal_Type_Declaration)
1086 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1089 if Nkind (T_Def) = N_Access_Function_Definition then
1090 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1092 Acc : constant Node_Id := Result_Definition (T_Def);
1095 if Present (Access_To_Subprogram_Definition (Acc))
1097 Protected_Present (Access_To_Subprogram_Definition (Acc))
1101 Replace_Anonymous_Access_To_Protected_Subprogram
1107 Access_Definition (T_Def, Result_Definition (T_Def)));
1112 Analyze (Result_Definition (T_Def));
1115 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1118 -- If a null exclusion is imposed on the result type, then
1119 -- create a null-excluding itype (an access subtype) and use
1120 -- it as the function's Etype.
1122 if Is_Access_Type (Typ)
1123 and then Null_Exclusion_In_Return_Present (T_Def)
1125 Set_Etype (Desig_Type,
1126 Create_Null_Excluding_Itype
1128 Related_Nod => T_Def,
1129 Scope_Id => Current_Scope));
1132 if From_With_Type (Typ) then
1134 -- AI05-151: Incomplete types are allowed in all basic
1135 -- declarations, including access to subprograms.
1137 if Ada_Version >= Ada_2012 then
1142 ("illegal use of incomplete type&",
1143 Result_Definition (T_Def), Typ);
1146 elsif Ekind (Current_Scope) = E_Package
1147 and then In_Private_Part (Current_Scope)
1149 if Ekind (Typ) = E_Incomplete_Type then
1150 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1152 elsif Is_Class_Wide_Type (Typ)
1153 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1156 (Desig_Type, Private_Dependents (Etype (Typ)));
1160 Set_Etype (Desig_Type, Typ);
1165 if not (Is_Type (Etype (Desig_Type))) then
1167 ("expect type in function specification",
1168 Result_Definition (T_Def));
1172 Set_Etype (Desig_Type, Standard_Void_Type);
1175 if Present (Formals) then
1176 Push_Scope (Desig_Type);
1178 -- A bit of a kludge here. These kludges will be removed when Itypes
1179 -- have proper parent pointers to their declarations???
1181 -- Kludge 1) Link defining_identifier of formals. Required by
1182 -- First_Formal to provide its functionality.
1188 F := First (Formals);
1190 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1191 -- when it is part of an unconstrained type and subtype expansion
1192 -- is disabled. To avoid back-end problems with shared profiles,
1193 -- use previous subprogram type as the designated type.
1196 and then Present (Scope (Defining_Identifier (F)))
1198 Set_Etype (T_Name, T_Name);
1199 Init_Size_Align (T_Name);
1200 Set_Directly_Designated_Type (T_Name,
1201 Scope (Defining_Identifier (F)));
1205 while Present (F) loop
1206 if No (Parent (Defining_Identifier (F))) then
1207 Set_Parent (Defining_Identifier (F), F);
1214 Process_Formals (Formals, Parent (T_Def));
1216 -- Kludge 2) End_Scope requires that the parent pointer be set to
1217 -- something reasonable, but Itypes don't have parent pointers. So
1218 -- we set it and then unset it ???
1220 Set_Parent (Desig_Type, T_Name);
1222 Set_Parent (Desig_Type, Empty);
1225 -- Check for premature usage of the type being defined
1227 Check_For_Premature_Usage (T_Def);
1229 -- The return type and/or any parameter type may be incomplete. Mark
1230 -- the subprogram_type as depending on the incomplete type, so that
1231 -- it can be updated when the full type declaration is seen. This
1232 -- only applies to incomplete types declared in some enclosing scope,
1233 -- not to limited views from other packages.
1235 if Present (Formals) then
1236 Formal := First_Formal (Desig_Type);
1237 while Present (Formal) loop
1238 if Ekind (Formal) /= E_In_Parameter
1239 and then Nkind (T_Def) = N_Access_Function_Definition
1241 Error_Msg_N ("functions can only have IN parameters", Formal);
1244 if Ekind (Etype (Formal)) = E_Incomplete_Type
1245 and then In_Open_Scopes (Scope (Etype (Formal)))
1247 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1248 Set_Has_Delayed_Freeze (Desig_Type);
1251 Next_Formal (Formal);
1255 -- If the return type is incomplete, this is legal as long as the
1256 -- type is declared in the current scope and will be completed in
1257 -- it (rather than being part of limited view).
1259 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1260 and then not Has_Delayed_Freeze (Desig_Type)
1261 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1263 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1264 Set_Has_Delayed_Freeze (Desig_Type);
1267 Check_Delayed_Subprogram (Desig_Type);
1269 if Protected_Present (T_Def) then
1270 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1271 Set_Convention (Desig_Type, Convention_Protected);
1273 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1276 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1278 Set_Etype (T_Name, T_Name);
1279 Init_Size_Align (T_Name);
1280 Set_Directly_Designated_Type (T_Name, Desig_Type);
1282 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1284 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1286 Check_Restriction (No_Access_Subprograms, T_Def);
1287 end Access_Subprogram_Declaration;
1289 ----------------------------
1290 -- Access_Type_Declaration --
1291 ----------------------------
1293 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1294 P : constant Node_Id := Parent (Def);
1295 S : constant Node_Id := Subtype_Indication (Def);
1297 Full_Desig : Entity_Id;
1300 Check_SPARK_Restriction ("access type is not allowed", Def);
1302 -- Check for permissible use of incomplete type
1304 if Nkind (S) /= N_Subtype_Indication then
1307 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1308 Set_Directly_Designated_Type (T, Entity (S));
1310 Set_Directly_Designated_Type (T,
1311 Process_Subtype (S, P, T, 'P'));
1315 Set_Directly_Designated_Type (T,
1316 Process_Subtype (S, P, T, 'P'));
1319 if All_Present (Def) or Constant_Present (Def) then
1320 Set_Ekind (T, E_General_Access_Type);
1322 Set_Ekind (T, E_Access_Type);
1325 Full_Desig := Designated_Type (T);
1327 if Base_Type (Full_Desig) = T then
1328 Error_Msg_N ("access type cannot designate itself", S);
1330 -- In Ada 2005, the type may have a limited view through some unit
1331 -- in its own context, allowing the following circularity that cannot
1332 -- be detected earlier
1334 elsif Is_Class_Wide_Type (Full_Desig)
1335 and then Etype (Full_Desig) = T
1338 ("access type cannot designate its own classwide type", S);
1340 -- Clean up indication of tagged status to prevent cascaded errors
1342 Set_Is_Tagged_Type (T, False);
1347 -- If the type has appeared already in a with_type clause, it is
1348 -- frozen and the pointer size is already set. Else, initialize.
1350 if not From_With_Type (T) then
1351 Init_Size_Align (T);
1354 -- Note that Has_Task is always false, since the access type itself
1355 -- is not a task type. See Einfo for more description on this point.
1356 -- Exactly the same consideration applies to Has_Controlled_Component.
1358 Set_Has_Task (T, False);
1359 Set_Has_Controlled_Component (T, False);
1361 -- Initialize field Finalization_Master explicitly to Empty, to avoid
1362 -- problems where an incomplete view of this entity has been previously
1363 -- established by a limited with and an overlaid version of this field
1364 -- (Stored_Constraint) was initialized for the incomplete view.
1366 -- This reset is performed in most cases except where the access type
1367 -- has been created for the purposes of allocating or deallocating a
1368 -- build-in-place object. Such access types have explicitly set pools
1369 -- and finalization masters.
1371 if No (Associated_Storage_Pool (T)) then
1372 Set_Finalization_Master (T, Empty);
1375 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1378 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1379 Set_Is_Access_Constant (T, Constant_Present (Def));
1380 end Access_Type_Declaration;
1382 ----------------------------------
1383 -- Add_Interface_Tag_Components --
1384 ----------------------------------
1386 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1387 Loc : constant Source_Ptr := Sloc (N);
1391 procedure Add_Tag (Iface : Entity_Id);
1392 -- Add tag for one of the progenitor interfaces
1398 procedure Add_Tag (Iface : Entity_Id) is
1405 pragma Assert (Is_Tagged_Type (Iface)
1406 and then Is_Interface (Iface));
1408 -- This is a reasonable place to propagate predicates
1410 if Has_Predicates (Iface) then
1411 Set_Has_Predicates (Typ);
1415 Make_Component_Definition (Loc,
1416 Aliased_Present => True,
1417 Subtype_Indication =>
1418 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1420 Tag := Make_Temporary (Loc, 'V');
1423 Make_Component_Declaration (Loc,
1424 Defining_Identifier => Tag,
1425 Component_Definition => Def);
1427 Analyze_Component_Declaration (Decl);
1429 Set_Analyzed (Decl);
1430 Set_Ekind (Tag, E_Component);
1432 Set_Is_Aliased (Tag);
1433 Set_Related_Type (Tag, Iface);
1434 Init_Component_Location (Tag);
1436 pragma Assert (Is_Frozen (Iface));
1438 Set_DT_Entry_Count (Tag,
1439 DT_Entry_Count (First_Entity (Iface)));
1441 if No (Last_Tag) then
1444 Insert_After (Last_Tag, Decl);
1449 -- If the ancestor has discriminants we need to give special support
1450 -- to store the offset_to_top value of the secondary dispatch tables.
1451 -- For this purpose we add a supplementary component just after the
1452 -- field that contains the tag associated with each secondary DT.
1454 if Typ /= Etype (Typ)
1455 and then Has_Discriminants (Etype (Typ))
1458 Make_Component_Definition (Loc,
1459 Subtype_Indication =>
1460 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1462 Offset := Make_Temporary (Loc, 'V');
1465 Make_Component_Declaration (Loc,
1466 Defining_Identifier => Offset,
1467 Component_Definition => Def);
1469 Analyze_Component_Declaration (Decl);
1471 Set_Analyzed (Decl);
1472 Set_Ekind (Offset, E_Component);
1473 Set_Is_Aliased (Offset);
1474 Set_Related_Type (Offset, Iface);
1475 Init_Component_Location (Offset);
1476 Insert_After (Last_Tag, Decl);
1487 -- Start of processing for Add_Interface_Tag_Components
1490 if not RTE_Available (RE_Interface_Tag) then
1492 ("(Ada 2005) interface types not supported by this run-time!",
1497 if Ekind (Typ) /= E_Record_Type
1498 or else (Is_Concurrent_Record_Type (Typ)
1499 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1500 or else (not Is_Concurrent_Record_Type (Typ)
1501 and then No (Interfaces (Typ))
1502 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1507 -- Find the current last tag
1509 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1510 Ext := Record_Extension_Part (Type_Definition (N));
1512 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1513 Ext := Type_Definition (N);
1518 if not (Present (Component_List (Ext))) then
1519 Set_Null_Present (Ext, False);
1521 Set_Component_List (Ext,
1522 Make_Component_List (Loc,
1523 Component_Items => L,
1524 Null_Present => False));
1526 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1527 L := Component_Items
1529 (Record_Extension_Part
1530 (Type_Definition (N))));
1532 L := Component_Items
1534 (Type_Definition (N)));
1537 -- Find the last tag component
1540 while Present (Comp) loop
1541 if Nkind (Comp) = N_Component_Declaration
1542 and then Is_Tag (Defining_Identifier (Comp))
1551 -- At this point L references the list of components and Last_Tag
1552 -- references the current last tag (if any). Now we add the tag
1553 -- corresponding with all the interfaces that are not implemented
1556 if Present (Interfaces (Typ)) then
1557 Elmt := First_Elmt (Interfaces (Typ));
1558 while Present (Elmt) loop
1559 Add_Tag (Node (Elmt));
1563 end Add_Interface_Tag_Components;
1565 -------------------------------------
1566 -- Add_Internal_Interface_Entities --
1567 -------------------------------------
1569 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1572 Iface_Elmt : Elmt_Id;
1573 Iface_Prim : Entity_Id;
1574 Ifaces_List : Elist_Id;
1575 New_Subp : Entity_Id := Empty;
1577 Restore_Scope : Boolean := False;
1580 pragma Assert (Ada_Version >= Ada_2005
1581 and then Is_Record_Type (Tagged_Type)
1582 and then Is_Tagged_Type (Tagged_Type)
1583 and then Has_Interfaces (Tagged_Type)
1584 and then not Is_Interface (Tagged_Type));
1586 -- Ensure that the internal entities are added to the scope of the type
1588 if Scope (Tagged_Type) /= Current_Scope then
1589 Push_Scope (Scope (Tagged_Type));
1590 Restore_Scope := True;
1593 Collect_Interfaces (Tagged_Type, Ifaces_List);
1595 Iface_Elmt := First_Elmt (Ifaces_List);
1596 while Present (Iface_Elmt) loop
1597 Iface := Node (Iface_Elmt);
1599 -- Originally we excluded here from this processing interfaces that
1600 -- are parents of Tagged_Type because their primitives are located
1601 -- in the primary dispatch table (and hence no auxiliary internal
1602 -- entities are required to handle secondary dispatch tables in such
1603 -- case). However, these auxiliary entities are also required to
1604 -- handle derivations of interfaces in formals of generics (see
1605 -- Derive_Subprograms).
1607 Elmt := First_Elmt (Primitive_Operations (Iface));
1608 while Present (Elmt) loop
1609 Iface_Prim := Node (Elmt);
1611 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1613 Find_Primitive_Covering_Interface
1614 (Tagged_Type => Tagged_Type,
1615 Iface_Prim => Iface_Prim);
1617 if No (Prim) and then Serious_Errors_Detected > 0 then
1621 pragma Assert (Present (Prim));
1623 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1624 -- differs from the name of the interface primitive then it is
1625 -- a private primitive inherited from a parent type. In such
1626 -- case, given that Tagged_Type covers the interface, the
1627 -- inherited private primitive becomes visible. For such
1628 -- purpose we add a new entity that renames the inherited
1629 -- private primitive.
1631 if Chars (Prim) /= Chars (Iface_Prim) then
1632 pragma Assert (Has_Suffix (Prim, 'P'));
1634 (New_Subp => New_Subp,
1635 Parent_Subp => Iface_Prim,
1636 Derived_Type => Tagged_Type,
1637 Parent_Type => Iface);
1638 Set_Alias (New_Subp, Prim);
1639 Set_Is_Abstract_Subprogram
1640 (New_Subp, Is_Abstract_Subprogram (Prim));
1644 (New_Subp => New_Subp,
1645 Parent_Subp => Iface_Prim,
1646 Derived_Type => Tagged_Type,
1647 Parent_Type => Iface);
1649 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1650 -- associated with interface types. These entities are
1651 -- only registered in the list of primitives of its
1652 -- corresponding tagged type because they are only used
1653 -- to fill the contents of the secondary dispatch tables.
1654 -- Therefore they are removed from the homonym chains.
1656 Set_Is_Hidden (New_Subp);
1657 Set_Is_Internal (New_Subp);
1658 Set_Alias (New_Subp, Prim);
1659 Set_Is_Abstract_Subprogram
1660 (New_Subp, Is_Abstract_Subprogram (Prim));
1661 Set_Interface_Alias (New_Subp, Iface_Prim);
1663 -- Internal entities associated with interface types are
1664 -- only registered in the list of primitives of the tagged
1665 -- type. They are only used to fill the contents of the
1666 -- secondary dispatch tables. Therefore they are not needed
1667 -- in the homonym chains.
1669 Remove_Homonym (New_Subp);
1671 -- Hidden entities associated with interfaces must have set
1672 -- the Has_Delay_Freeze attribute to ensure that, in case of
1673 -- locally defined tagged types (or compiling with static
1674 -- dispatch tables generation disabled) the corresponding
1675 -- entry of the secondary dispatch table is filled when
1676 -- such an entity is frozen.
1678 Set_Has_Delayed_Freeze (New_Subp);
1685 Next_Elmt (Iface_Elmt);
1688 if Restore_Scope then
1691 end Add_Internal_Interface_Entities;
1693 -----------------------------------
1694 -- Analyze_Component_Declaration --
1695 -----------------------------------
1697 procedure Analyze_Component_Declaration (N : Node_Id) is
1698 Id : constant Entity_Id := Defining_Identifier (N);
1699 E : constant Node_Id := Expression (N);
1700 Typ : constant Node_Id :=
1701 Subtype_Indication (Component_Definition (N));
1705 function Contains_POC (Constr : Node_Id) return Boolean;
1706 -- Determines whether a constraint uses the discriminant of a record
1707 -- type thus becoming a per-object constraint (POC).
1709 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1710 -- Typ is the type of the current component, check whether this type is
1711 -- a limited type. Used to validate declaration against that of
1712 -- enclosing record.
1718 function Contains_POC (Constr : Node_Id) return Boolean is
1720 -- Prevent cascaded errors
1722 if Error_Posted (Constr) then
1726 case Nkind (Constr) is
1727 when N_Attribute_Reference =>
1729 Attribute_Name (Constr) = Name_Access
1730 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1732 when N_Discriminant_Association =>
1733 return Denotes_Discriminant (Expression (Constr));
1735 when N_Identifier =>
1736 return Denotes_Discriminant (Constr);
1738 when N_Index_Or_Discriminant_Constraint =>
1743 IDC := First (Constraints (Constr));
1744 while Present (IDC) loop
1746 -- One per-object constraint is sufficient
1748 if Contains_POC (IDC) then
1759 return Denotes_Discriminant (Low_Bound (Constr))
1761 Denotes_Discriminant (High_Bound (Constr));
1763 when N_Range_Constraint =>
1764 return Denotes_Discriminant (Range_Expression (Constr));
1772 ----------------------
1773 -- Is_Known_Limited --
1774 ----------------------
1776 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1777 P : constant Entity_Id := Etype (Typ);
1778 R : constant Entity_Id := Root_Type (Typ);
1781 if Is_Limited_Record (Typ) then
1784 -- If the root type is limited (and not a limited interface)
1785 -- so is the current type
1787 elsif Is_Limited_Record (R)
1789 (not Is_Interface (R)
1790 or else not Is_Limited_Interface (R))
1794 -- Else the type may have a limited interface progenitor, but a
1795 -- limited record parent.
1798 and then Is_Limited_Record (P)
1805 end Is_Known_Limited;
1807 -- Start of processing for Analyze_Component_Declaration
1810 Generate_Definition (Id);
1813 if Present (Typ) then
1814 T := Find_Type_Of_Object
1815 (Subtype_Indication (Component_Definition (N)), N);
1817 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1818 Check_SPARK_Restriction ("subtype mark required", Typ);
1821 -- Ada 2005 (AI-230): Access Definition case
1824 pragma Assert (Present
1825 (Access_Definition (Component_Definition (N))));
1827 T := Access_Definition
1829 N => Access_Definition (Component_Definition (N)));
1830 Set_Is_Local_Anonymous_Access (T);
1832 -- Ada 2005 (AI-254)
1834 if Present (Access_To_Subprogram_Definition
1835 (Access_Definition (Component_Definition (N))))
1836 and then Protected_Present (Access_To_Subprogram_Definition
1838 (Component_Definition (N))))
1840 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1844 -- If the subtype is a constrained subtype of the enclosing record,
1845 -- (which must have a partial view) the back-end does not properly
1846 -- handle the recursion. Rewrite the component declaration with an
1847 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1848 -- the tree directly because side effects have already been removed from
1849 -- discriminant constraints.
1851 if Ekind (T) = E_Access_Subtype
1852 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1853 and then Comes_From_Source (T)
1854 and then Nkind (Parent (T)) = N_Subtype_Declaration
1855 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1858 (Subtype_Indication (Component_Definition (N)),
1859 New_Copy_Tree (Subtype_Indication (Parent (T))));
1860 T := Find_Type_Of_Object
1861 (Subtype_Indication (Component_Definition (N)), N);
1864 -- If the component declaration includes a default expression, then we
1865 -- check that the component is not of a limited type (RM 3.7(5)),
1866 -- and do the special preanalysis of the expression (see section on
1867 -- "Handling of Default and Per-Object Expressions" in the spec of
1871 Check_SPARK_Restriction ("default expression is not allowed", E);
1872 Preanalyze_Spec_Expression (E, T);
1873 Check_Initialization (T, E);
1875 if Ada_Version >= Ada_2005
1876 and then Ekind (T) = E_Anonymous_Access_Type
1877 and then Etype (E) /= Any_Type
1879 -- Check RM 3.9.2(9): "if the expected type for an expression is
1880 -- an anonymous access-to-specific tagged type, then the object
1881 -- designated by the expression shall not be dynamically tagged
1882 -- unless it is a controlling operand in a call on a dispatching
1885 if Is_Tagged_Type (Directly_Designated_Type (T))
1887 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1889 Ekind (Directly_Designated_Type (Etype (E))) =
1893 ("access to specific tagged type required (RM 3.9.2(9))", E);
1896 -- (Ada 2005: AI-230): Accessibility check for anonymous
1899 if Type_Access_Level (Etype (E)) >
1900 Deepest_Type_Access_Level (T)
1903 ("expression has deeper access level than component " &
1904 "(RM 3.10.2 (12.2))", E);
1907 -- The initialization expression is a reference to an access
1908 -- discriminant. The type of the discriminant is always deeper
1909 -- than any access type.
1911 if Ekind (Etype (E)) = E_Anonymous_Access_Type
1912 and then Is_Entity_Name (E)
1913 and then Ekind (Entity (E)) = E_In_Parameter
1914 and then Present (Discriminal_Link (Entity (E)))
1917 ("discriminant has deeper accessibility level than target",
1923 -- The parent type may be a private view with unknown discriminants,
1924 -- and thus unconstrained. Regular components must be constrained.
1926 if Is_Indefinite_Subtype (T) and then Chars (Id) /= Name_uParent then
1927 if Is_Class_Wide_Type (T) then
1929 ("class-wide subtype with unknown discriminants" &
1930 " in component declaration",
1931 Subtype_Indication (Component_Definition (N)));
1934 ("unconstrained subtype in component declaration",
1935 Subtype_Indication (Component_Definition (N)));
1938 -- Components cannot be abstract, except for the special case of
1939 -- the _Parent field (case of extending an abstract tagged type)
1941 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
1942 Error_Msg_N ("type of a component cannot be abstract", N);
1946 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
1948 -- The component declaration may have a per-object constraint, set
1949 -- the appropriate flag in the defining identifier of the subtype.
1951 if Present (Subtype_Indication (Component_Definition (N))) then
1953 Sindic : constant Node_Id :=
1954 Subtype_Indication (Component_Definition (N));
1956 if Nkind (Sindic) = N_Subtype_Indication
1957 and then Present (Constraint (Sindic))
1958 and then Contains_POC (Constraint (Sindic))
1960 Set_Has_Per_Object_Constraint (Id);
1965 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
1966 -- out some static checks.
1968 if Ada_Version >= Ada_2005
1969 and then Can_Never_Be_Null (T)
1971 Null_Exclusion_Static_Checks (N);
1974 -- If this component is private (or depends on a private type), flag the
1975 -- record type to indicate that some operations are not available.
1977 P := Private_Component (T);
1981 -- Check for circular definitions
1983 if P = Any_Type then
1984 Set_Etype (Id, Any_Type);
1986 -- There is a gap in the visibility of operations only if the
1987 -- component type is not defined in the scope of the record type.
1989 elsif Scope (P) = Scope (Current_Scope) then
1992 elsif Is_Limited_Type (P) then
1993 Set_Is_Limited_Composite (Current_Scope);
1996 Set_Is_Private_Composite (Current_Scope);
2001 and then Is_Limited_Type (T)
2002 and then Chars (Id) /= Name_uParent
2003 and then Is_Tagged_Type (Current_Scope)
2005 if Is_Derived_Type (Current_Scope)
2006 and then not Is_Known_Limited (Current_Scope)
2009 ("extension of nonlimited type cannot have limited components",
2012 if Is_Interface (Root_Type (Current_Scope)) then
2014 ("\limitedness is not inherited from limited interface", N);
2015 Error_Msg_N ("\add LIMITED to type indication", N);
2018 Explain_Limited_Type (T, N);
2019 Set_Etype (Id, Any_Type);
2020 Set_Is_Limited_Composite (Current_Scope, False);
2022 elsif not Is_Derived_Type (Current_Scope)
2023 and then not Is_Limited_Record (Current_Scope)
2024 and then not Is_Concurrent_Type (Current_Scope)
2027 ("nonlimited tagged type cannot have limited components", N);
2028 Explain_Limited_Type (T, N);
2029 Set_Etype (Id, Any_Type);
2030 Set_Is_Limited_Composite (Current_Scope, False);
2034 Set_Original_Record_Component (Id, Id);
2036 if Has_Aspects (N) then
2037 Analyze_Aspect_Specifications (N, Id);
2039 end Analyze_Component_Declaration;
2041 --------------------------
2042 -- Analyze_Declarations --
2043 --------------------------
2045 procedure Analyze_Declarations (L : List_Id) is
2047 Freeze_From : Entity_Id := Empty;
2048 Next_Node : Node_Id;
2051 -- Adjust D not to include implicit label declarations, since these
2052 -- have strange Sloc values that result in elaboration check problems.
2053 -- (They have the sloc of the label as found in the source, and that
2054 -- is ahead of the current declarative part).
2060 procedure Adjust_D is
2062 while Present (Prev (D))
2063 and then Nkind (D) = N_Implicit_Label_Declaration
2069 -- Start of processing for Analyze_Declarations
2072 if Restriction_Check_Required (SPARK) then
2073 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2077 while Present (D) loop
2079 -- Package spec cannot contain a package declaration in SPARK
2081 if Nkind (D) = N_Package_Declaration
2082 and then Nkind (Parent (L)) = N_Package_Specification
2084 Check_SPARK_Restriction
2085 ("package specification cannot contain a package declaration",
2089 -- Complete analysis of declaration
2092 Next_Node := Next (D);
2094 if No (Freeze_From) then
2095 Freeze_From := First_Entity (Current_Scope);
2098 -- At the end of a declarative part, freeze remaining entities
2099 -- declared in it. The end of the visible declarations of package
2100 -- specification is not the end of a declarative part if private
2101 -- declarations are present. The end of a package declaration is a
2102 -- freezing point only if it a library package. A task definition or
2103 -- protected type definition is not a freeze point either. Finally,
2104 -- we do not freeze entities in generic scopes, because there is no
2105 -- code generated for them and freeze nodes will be generated for
2108 -- The end of a package instantiation is not a freeze point, but
2109 -- for now we make it one, because the generic body is inserted
2110 -- (currently) immediately after. Generic instantiations will not
2111 -- be a freeze point once delayed freezing of bodies is implemented.
2112 -- (This is needed in any case for early instantiations ???).
2114 if No (Next_Node) then
2115 if Nkind_In (Parent (L), N_Component_List,
2117 N_Protected_Definition)
2121 elsif Nkind (Parent (L)) /= N_Package_Specification then
2122 if Nkind (Parent (L)) = N_Package_Body then
2123 Freeze_From := First_Entity (Current_Scope);
2127 Freeze_All (Freeze_From, D);
2128 Freeze_From := Last_Entity (Current_Scope);
2130 elsif Scope (Current_Scope) /= Standard_Standard
2131 and then not Is_Child_Unit (Current_Scope)
2132 and then No (Generic_Parent (Parent (L)))
2136 elsif L /= Visible_Declarations (Parent (L))
2137 or else No (Private_Declarations (Parent (L)))
2138 or else Is_Empty_List (Private_Declarations (Parent (L)))
2141 Freeze_All (Freeze_From, D);
2142 Freeze_From := Last_Entity (Current_Scope);
2145 -- If next node is a body then freeze all types before the body.
2146 -- An exception occurs for some expander-generated bodies. If these
2147 -- are generated at places where in general language rules would not
2148 -- allow a freeze point, then we assume that the expander has
2149 -- explicitly checked that all required types are properly frozen,
2150 -- and we do not cause general freezing here. This special circuit
2151 -- is used when the encountered body is marked as having already
2154 -- In all other cases (bodies that come from source, and expander
2155 -- generated bodies that have not been analyzed yet), freeze all
2156 -- types now. Note that in the latter case, the expander must take
2157 -- care to attach the bodies at a proper place in the tree so as to
2158 -- not cause unwanted freezing at that point.
2160 elsif not Analyzed (Next_Node)
2161 and then (Nkind_In (Next_Node, N_Subprogram_Body,
2167 Nkind (Next_Node) in N_Body_Stub)
2170 Freeze_All (Freeze_From, D);
2171 Freeze_From := Last_Entity (Current_Scope);
2177 -- One more thing to do, we need to scan the declarations to check
2178 -- for any precondition/postcondition pragmas (Pre/Post aspects have
2179 -- by this stage been converted into corresponding pragmas). It is
2180 -- at this point that we analyze the expressions in such pragmas,
2181 -- to implement the delayed visibility requirement.
2191 while Present (Decl) loop
2192 if Nkind (Original_Node (Decl)) = N_Subprogram_Declaration then
2193 Spec := Specification (Original_Node (Decl));
2194 Sent := Defining_Unit_Name (Spec);
2196 Prag := Spec_PPC_List (Contract (Sent));
2197 while Present (Prag) loop
2198 Analyze_PPC_In_Decl_Part (Prag, Sent);
2199 Prag := Next_Pragma (Prag);
2202 Check_Subprogram_Contract (Sent);
2204 Prag := Spec_TC_List (Contract (Sent));
2205 while Present (Prag) loop
2206 Analyze_TC_In_Decl_Part (Prag, Sent);
2207 Prag := Next_Pragma (Prag);
2214 end Analyze_Declarations;
2216 -----------------------------------
2217 -- Analyze_Full_Type_Declaration --
2218 -----------------------------------
2220 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2221 Def : constant Node_Id := Type_Definition (N);
2222 Def_Id : constant Entity_Id := Defining_Identifier (N);
2226 Is_Remote : constant Boolean :=
2227 (Is_Remote_Types (Current_Scope)
2228 or else Is_Remote_Call_Interface (Current_Scope))
2229 and then not (In_Private_Part (Current_Scope)
2230 or else In_Package_Body (Current_Scope));
2232 procedure Check_Ops_From_Incomplete_Type;
2233 -- If there is a tagged incomplete partial view of the type, traverse
2234 -- the primitives of the incomplete view and change the type of any
2235 -- controlling formals and result to indicate the full view. The
2236 -- primitives will be added to the full type's primitive operations
2237 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2238 -- is called from Process_Incomplete_Dependents).
2240 ------------------------------------
2241 -- Check_Ops_From_Incomplete_Type --
2242 ------------------------------------
2244 procedure Check_Ops_From_Incomplete_Type is
2251 and then Ekind (Prev) = E_Incomplete_Type
2252 and then Is_Tagged_Type (Prev)
2253 and then Is_Tagged_Type (T)
2255 Elmt := First_Elmt (Primitive_Operations (Prev));
2256 while Present (Elmt) loop
2259 Formal := First_Formal (Op);
2260 while Present (Formal) loop
2261 if Etype (Formal) = Prev then
2262 Set_Etype (Formal, T);
2265 Next_Formal (Formal);
2268 if Etype (Op) = Prev then
2275 end Check_Ops_From_Incomplete_Type;
2277 -- Start of processing for Analyze_Full_Type_Declaration
2280 Prev := Find_Type_Name (N);
2282 -- The full view, if present, now points to the current type
2284 -- Ada 2005 (AI-50217): If the type was previously decorated when
2285 -- imported through a LIMITED WITH clause, it appears as incomplete
2286 -- but has no full view.
2288 if Ekind (Prev) = E_Incomplete_Type
2289 and then Present (Full_View (Prev))
2291 T := Full_View (Prev);
2296 Set_Is_Pure (T, Is_Pure (Current_Scope));
2298 -- We set the flag Is_First_Subtype here. It is needed to set the
2299 -- corresponding flag for the Implicit class-wide-type created
2300 -- during tagged types processing.
2302 Set_Is_First_Subtype (T, True);
2304 -- Only composite types other than array types are allowed to have
2309 -- For derived types, the rule will be checked once we've figured
2310 -- out the parent type.
2312 when N_Derived_Type_Definition =>
2315 -- For record types, discriminants are allowed, unless we are in
2318 when N_Record_Definition =>
2319 if Present (Discriminant_Specifications (N)) then
2320 Check_SPARK_Restriction
2321 ("discriminant type is not allowed",
2323 (First (Discriminant_Specifications (N))));
2327 if Present (Discriminant_Specifications (N)) then
2329 ("elementary or array type cannot have discriminants",
2331 (First (Discriminant_Specifications (N))));
2335 -- Elaborate the type definition according to kind, and generate
2336 -- subsidiary (implicit) subtypes where needed. We skip this if it was
2337 -- already done (this happens during the reanalysis that follows a call
2338 -- to the high level optimizer).
2340 if not Analyzed (T) then
2345 when N_Access_To_Subprogram_Definition =>
2346 Access_Subprogram_Declaration (T, Def);
2348 -- If this is a remote access to subprogram, we must create the
2349 -- equivalent fat pointer type, and related subprograms.
2352 Process_Remote_AST_Declaration (N);
2355 -- Validate categorization rule against access type declaration
2356 -- usually a violation in Pure unit, Shared_Passive unit.
2358 Validate_Access_Type_Declaration (T, N);
2360 when N_Access_To_Object_Definition =>
2361 Access_Type_Declaration (T, Def);
2363 -- Validate categorization rule against access type declaration
2364 -- usually a violation in Pure unit, Shared_Passive unit.
2366 Validate_Access_Type_Declaration (T, N);
2368 -- If we are in a Remote_Call_Interface package and define a
2369 -- RACW, then calling stubs and specific stream attributes
2373 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
2375 Add_RACW_Features (Def_Id);
2378 -- Set no strict aliasing flag if config pragma seen
2380 if Opt.No_Strict_Aliasing then
2381 Set_No_Strict_Aliasing (Base_Type (Def_Id));
2384 when N_Array_Type_Definition =>
2385 Array_Type_Declaration (T, Def);
2387 when N_Derived_Type_Definition =>
2388 Derived_Type_Declaration (T, N, T /= Def_Id);
2390 when N_Enumeration_Type_Definition =>
2391 Enumeration_Type_Declaration (T, Def);
2393 when N_Floating_Point_Definition =>
2394 Floating_Point_Type_Declaration (T, Def);
2396 when N_Decimal_Fixed_Point_Definition =>
2397 Decimal_Fixed_Point_Type_Declaration (T, Def);
2399 when N_Ordinary_Fixed_Point_Definition =>
2400 Ordinary_Fixed_Point_Type_Declaration (T, Def);
2402 when N_Signed_Integer_Type_Definition =>
2403 Signed_Integer_Type_Declaration (T, Def);
2405 when N_Modular_Type_Definition =>
2406 Modular_Type_Declaration (T, Def);
2408 when N_Record_Definition =>
2409 Record_Type_Declaration (T, N, Prev);
2411 -- If declaration has a parse error, nothing to elaborate.
2417 raise Program_Error;
2422 if Etype (T) = Any_Type then
2426 -- Controlled type is not allowed in SPARK
2428 if Is_Visibly_Controlled (T) then
2429 Check_SPARK_Restriction ("controlled type is not allowed", N);
2432 -- Some common processing for all types
2434 Set_Depends_On_Private (T, Has_Private_Component (T));
2435 Check_Ops_From_Incomplete_Type;
2437 -- Both the declared entity, and its anonymous base type if one
2438 -- was created, need freeze nodes allocated.
2441 B : constant Entity_Id := Base_Type (T);
2444 -- In the case where the base type differs from the first subtype, we
2445 -- pre-allocate a freeze node, and set the proper link to the first
2446 -- subtype. Freeze_Entity will use this preallocated freeze node when
2447 -- it freezes the entity.
2449 -- This does not apply if the base type is a generic type, whose
2450 -- declaration is independent of the current derived definition.
2452 if B /= T and then not Is_Generic_Type (B) then
2453 Ensure_Freeze_Node (B);
2454 Set_First_Subtype_Link (Freeze_Node (B), T);
2457 -- A type that is imported through a limited_with clause cannot
2458 -- generate any code, and thus need not be frozen. However, an access
2459 -- type with an imported designated type needs a finalization list,
2460 -- which may be referenced in some other package that has non-limited
2461 -- visibility on the designated type. Thus we must create the
2462 -- finalization list at the point the access type is frozen, to
2463 -- prevent unsatisfied references at link time.
2465 if not From_With_Type (T) or else Is_Access_Type (T) then
2466 Set_Has_Delayed_Freeze (T);
2470 -- Case where T is the full declaration of some private type which has
2471 -- been swapped in Defining_Identifier (N).
2473 if T /= Def_Id and then Is_Private_Type (Def_Id) then
2474 Process_Full_View (N, T, Def_Id);
2476 -- Record the reference. The form of this is a little strange, since
2477 -- the full declaration has been swapped in. So the first parameter
2478 -- here represents the entity to which a reference is made which is
2479 -- the "real" entity, i.e. the one swapped in, and the second
2480 -- parameter provides the reference location.
2482 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
2483 -- since we don't want a complaint about the full type being an
2484 -- unwanted reference to the private type
2487 B : constant Boolean := Has_Pragma_Unreferenced (T);
2489 Set_Has_Pragma_Unreferenced (T, False);
2490 Generate_Reference (T, T, 'c');
2491 Set_Has_Pragma_Unreferenced (T, B);
2494 Set_Completion_Referenced (Def_Id);
2496 -- For completion of incomplete type, process incomplete dependents
2497 -- and always mark the full type as referenced (it is the incomplete
2498 -- type that we get for any real reference).
2500 elsif Ekind (Prev) = E_Incomplete_Type then
2501 Process_Incomplete_Dependents (N, T, Prev);
2502 Generate_Reference (Prev, Def_Id, 'c');
2503 Set_Completion_Referenced (Def_Id);
2505 -- If not private type or incomplete type completion, this is a real
2506 -- definition of a new entity, so record it.
2509 Generate_Definition (Def_Id);
2512 if Chars (Scope (Def_Id)) = Name_System
2513 and then Chars (Def_Id) = Name_Address
2514 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
2516 Set_Is_Descendent_Of_Address (Def_Id);
2517 Set_Is_Descendent_Of_Address (Base_Type (Def_Id));
2518 Set_Is_Descendent_Of_Address (Prev);
2521 Set_Optimize_Alignment_Flags (Def_Id);
2522 Check_Eliminated (Def_Id);
2524 -- If the declaration is a completion and aspects are present, apply
2525 -- them to the entity for the type which is currently the partial
2526 -- view, but which is the one that will be frozen.
2528 if Has_Aspects (N) then
2529 if Prev /= Def_Id then
2530 Analyze_Aspect_Specifications (N, Prev);
2532 Analyze_Aspect_Specifications (N, Def_Id);
2535 end Analyze_Full_Type_Declaration;
2537 ----------------------------------
2538 -- Analyze_Incomplete_Type_Decl --
2539 ----------------------------------
2541 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
2542 F : constant Boolean := Is_Pure (Current_Scope);
2546 Check_SPARK_Restriction ("incomplete type is not allowed", N);
2548 Generate_Definition (Defining_Identifier (N));
2550 -- Process an incomplete declaration. The identifier must not have been
2551 -- declared already in the scope. However, an incomplete declaration may
2552 -- appear in the private part of a package, for a private type that has
2553 -- already been declared.
2555 -- In this case, the discriminants (if any) must match
2557 T := Find_Type_Name (N);
2559 Set_Ekind (T, E_Incomplete_Type);
2560 Init_Size_Align (T);
2561 Set_Is_First_Subtype (T, True);
2564 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
2565 -- incomplete types.
2567 if Tagged_Present (N) then
2568 Set_Is_Tagged_Type (T);
2569 Make_Class_Wide_Type (T);
2570 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2575 Set_Stored_Constraint (T, No_Elist);
2577 if Present (Discriminant_Specifications (N)) then
2578 Process_Discriminants (N);
2583 -- If the type has discriminants, non-trivial subtypes may be
2584 -- declared before the full view of the type. The full views of those
2585 -- subtypes will be built after the full view of the type.
2587 Set_Private_Dependents (T, New_Elmt_List);
2589 end Analyze_Incomplete_Type_Decl;
2591 -----------------------------------
2592 -- Analyze_Interface_Declaration --
2593 -----------------------------------
2595 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
2596 CW : constant Entity_Id := Class_Wide_Type (T);
2599 Set_Is_Tagged_Type (T);
2601 Set_Is_Limited_Record (T, Limited_Present (Def)
2602 or else Task_Present (Def)
2603 or else Protected_Present (Def)
2604 or else Synchronized_Present (Def));
2606 -- Type is abstract if full declaration carries keyword, or if previous
2607 -- partial view did.
2609 Set_Is_Abstract_Type (T);
2610 Set_Is_Interface (T);
2612 -- Type is a limited interface if it includes the keyword limited, task,
2613 -- protected, or synchronized.
2615 Set_Is_Limited_Interface
2616 (T, Limited_Present (Def)
2617 or else Protected_Present (Def)
2618 or else Synchronized_Present (Def)
2619 or else Task_Present (Def));
2621 Set_Interfaces (T, New_Elmt_List);
2622 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2624 -- Complete the decoration of the class-wide entity if it was already
2625 -- built (i.e. during the creation of the limited view)
2627 if Present (CW) then
2628 Set_Is_Interface (CW);
2629 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
2632 -- Check runtime support for synchronized interfaces
2634 if VM_Target = No_VM
2635 and then (Is_Task_Interface (T)
2636 or else Is_Protected_Interface (T)
2637 or else Is_Synchronized_Interface (T))
2638 and then not RTE_Available (RE_Select_Specific_Data)
2640 Error_Msg_CRT ("synchronized interfaces", T);
2642 end Analyze_Interface_Declaration;
2644 -----------------------------
2645 -- Analyze_Itype_Reference --
2646 -----------------------------
2648 -- Nothing to do. This node is placed in the tree only for the benefit of
2649 -- back end processing, and has no effect on the semantic processing.
2651 procedure Analyze_Itype_Reference (N : Node_Id) is
2653 pragma Assert (Is_Itype (Itype (N)));
2655 end Analyze_Itype_Reference;
2657 --------------------------------
2658 -- Analyze_Number_Declaration --
2659 --------------------------------
2661 procedure Analyze_Number_Declaration (N : Node_Id) is
2662 Id : constant Entity_Id := Defining_Identifier (N);
2663 E : constant Node_Id := Expression (N);
2665 Index : Interp_Index;
2669 Generate_Definition (Id);
2672 -- This is an optimization of a common case of an integer literal
2674 if Nkind (E) = N_Integer_Literal then
2675 Set_Is_Static_Expression (E, True);
2676 Set_Etype (E, Universal_Integer);
2678 Set_Etype (Id, Universal_Integer);
2679 Set_Ekind (Id, E_Named_Integer);
2680 Set_Is_Frozen (Id, True);
2684 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2686 -- Process expression, replacing error by integer zero, to avoid
2687 -- cascaded errors or aborts further along in the processing
2689 -- Replace Error by integer zero, which seems least likely to cause
2693 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
2694 Set_Error_Posted (E);
2699 -- Verify that the expression is static and numeric. If
2700 -- the expression is overloaded, we apply the preference
2701 -- rule that favors root numeric types.
2703 if not Is_Overloaded (E) then
2709 Get_First_Interp (E, Index, It);
2710 while Present (It.Typ) loop
2711 if (Is_Integer_Type (It.Typ)
2712 or else Is_Real_Type (It.Typ))
2713 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
2715 if T = Any_Type then
2718 elsif It.Typ = Universal_Real
2719 or else It.Typ = Universal_Integer
2721 -- Choose universal interpretation over any other
2728 Get_Next_Interp (Index, It);
2732 if Is_Integer_Type (T) then
2734 Set_Etype (Id, Universal_Integer);
2735 Set_Ekind (Id, E_Named_Integer);
2737 elsif Is_Real_Type (T) then
2739 -- Because the real value is converted to universal_real, this is a
2740 -- legal context for a universal fixed expression.
2742 if T = Universal_Fixed then
2744 Loc : constant Source_Ptr := Sloc (N);
2745 Conv : constant Node_Id := Make_Type_Conversion (Loc,
2747 New_Occurrence_Of (Universal_Real, Loc),
2748 Expression => Relocate_Node (E));
2755 elsif T = Any_Fixed then
2756 Error_Msg_N ("illegal context for mixed mode operation", E);
2758 -- Expression is of the form : universal_fixed * integer. Try to
2759 -- resolve as universal_real.
2761 T := Universal_Real;
2766 Set_Etype (Id, Universal_Real);
2767 Set_Ekind (Id, E_Named_Real);
2770 Wrong_Type (E, Any_Numeric);
2774 Set_Ekind (Id, E_Constant);
2775 Set_Never_Set_In_Source (Id, True);
2776 Set_Is_True_Constant (Id, True);
2780 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
2781 Set_Etype (E, Etype (Id));
2784 if not Is_OK_Static_Expression (E) then
2785 Flag_Non_Static_Expr
2786 ("non-static expression used in number declaration!", E);
2787 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
2788 Set_Etype (E, Any_Type);
2790 end Analyze_Number_Declaration;
2792 --------------------------------
2793 -- Analyze_Object_Declaration --
2794 --------------------------------
2796 procedure Analyze_Object_Declaration (N : Node_Id) is
2797 Loc : constant Source_Ptr := Sloc (N);
2798 Id : constant Entity_Id := Defining_Identifier (N);
2802 E : Node_Id := Expression (N);
2803 -- E is set to Expression (N) throughout this routine. When
2804 -- Expression (N) is modified, E is changed accordingly.
2806 Prev_Entity : Entity_Id := Empty;
2808 function Count_Tasks (T : Entity_Id) return Uint;
2809 -- This function is called when a non-generic library level object of a
2810 -- task type is declared. Its function is to count the static number of
2811 -- tasks declared within the type (it is only called if Has_Tasks is set
2812 -- for T). As a side effect, if an array of tasks with non-static bounds
2813 -- or a variant record type is encountered, Check_Restrictions is called
2814 -- indicating the count is unknown.
2820 function Count_Tasks (T : Entity_Id) return Uint is
2826 if Is_Task_Type (T) then
2829 elsif Is_Record_Type (T) then
2830 if Has_Discriminants (T) then
2831 Check_Restriction (Max_Tasks, N);
2836 C := First_Component (T);
2837 while Present (C) loop
2838 V := V + Count_Tasks (Etype (C));
2845 elsif Is_Array_Type (T) then
2846 X := First_Index (T);
2847 V := Count_Tasks (Component_Type (T));
2848 while Present (X) loop
2851 if not Is_Static_Subtype (C) then
2852 Check_Restriction (Max_Tasks, N);
2855 V := V * (UI_Max (Uint_0,
2856 Expr_Value (Type_High_Bound (C)) -
2857 Expr_Value (Type_Low_Bound (C)) + Uint_1));
2870 -- Start of processing for Analyze_Object_Declaration
2873 -- There are three kinds of implicit types generated by an
2874 -- object declaration:
2876 -- 1. Those generated by the original Object Definition
2878 -- 2. Those generated by the Expression
2880 -- 3. Those used to constrain the Object Definition with the
2881 -- expression constraints when the definition is unconstrained.
2883 -- They must be generated in this order to avoid order of elaboration
2884 -- issues. Thus the first step (after entering the name) is to analyze
2885 -- the object definition.
2887 if Constant_Present (N) then
2888 Prev_Entity := Current_Entity_In_Scope (Id);
2890 if Present (Prev_Entity)
2893 -- If the homograph is an implicit subprogram, it is overridden
2894 -- by the current declaration.
2896 ((Is_Overloadable (Prev_Entity)
2897 and then Is_Inherited_Operation (Prev_Entity))
2899 -- The current object is a discriminal generated for an entry
2900 -- family index. Even though the index is a constant, in this
2901 -- particular context there is no true constant redeclaration.
2902 -- Enter_Name will handle the visibility.
2905 (Is_Discriminal (Id)
2906 and then Ekind (Discriminal_Link (Id)) =
2907 E_Entry_Index_Parameter)
2909 -- The current object is the renaming for a generic declared
2910 -- within the instance.
2913 (Ekind (Prev_Entity) = E_Package
2914 and then Nkind (Parent (Prev_Entity)) =
2915 N_Package_Renaming_Declaration
2916 and then not Comes_From_Source (Prev_Entity)
2917 and then Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
2919 Prev_Entity := Empty;
2923 if Present (Prev_Entity) then
2924 Constant_Redeclaration (Id, N, T);
2926 Generate_Reference (Prev_Entity, Id, 'c');
2927 Set_Completion_Referenced (Id);
2929 if Error_Posted (N) then
2931 -- Type mismatch or illegal redeclaration, Do not analyze
2932 -- expression to avoid cascaded errors.
2934 T := Find_Type_Of_Object (Object_Definition (N), N);
2936 Set_Ekind (Id, E_Variable);
2940 -- In the normal case, enter identifier at the start to catch premature
2941 -- usage in the initialization expression.
2944 Generate_Definition (Id);
2947 Mark_Coextensions (N, Object_Definition (N));
2949 T := Find_Type_Of_Object (Object_Definition (N), N);
2951 if Nkind (Object_Definition (N)) = N_Access_Definition
2953 (Access_To_Subprogram_Definition (Object_Definition (N)))
2954 and then Protected_Present
2955 (Access_To_Subprogram_Definition (Object_Definition (N)))
2957 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2960 if Error_Posted (Id) then
2962 Set_Ekind (Id, E_Variable);
2967 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2968 -- out some static checks
2970 if Ada_Version >= Ada_2005
2971 and then Can_Never_Be_Null (T)
2973 -- In case of aggregates we must also take care of the correct
2974 -- initialization of nested aggregates bug this is done at the
2975 -- point of the analysis of the aggregate (see sem_aggr.adb)
2977 if Present (Expression (N))
2978 and then Nkind (Expression (N)) = N_Aggregate
2984 Save_Typ : constant Entity_Id := Etype (Id);
2986 Set_Etype (Id, T); -- Temp. decoration for static checks
2987 Null_Exclusion_Static_Checks (N);
2988 Set_Etype (Id, Save_Typ);
2993 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2995 -- If deferred constant, make sure context is appropriate. We detect
2996 -- a deferred constant as a constant declaration with no expression.
2997 -- A deferred constant can appear in a package body if its completion
2998 -- is by means of an interface pragma.
3000 if Constant_Present (N)
3003 -- A deferred constant may appear in the declarative part of the
3004 -- following constructs:
3008 -- extended return statements
3011 -- subprogram bodies
3014 -- When declared inside a package spec, a deferred constant must be
3015 -- completed by a full constant declaration or pragma Import. In all
3016 -- other cases, the only proper completion is pragma Import. Extended
3017 -- return statements are flagged as invalid contexts because they do
3018 -- not have a declarative part and so cannot accommodate the pragma.
3020 if Ekind (Current_Scope) = E_Return_Statement then
3022 ("invalid context for deferred constant declaration (RM 7.4)",
3025 ("\declaration requires an initialization expression",
3027 Set_Constant_Present (N, False);
3029 -- In Ada 83, deferred constant must be of private type
3031 elsif not Is_Private_Type (T) then
3032 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
3034 ("(Ada 83) deferred constant must be private type", N);
3038 -- If not a deferred constant, then object declaration freezes its type
3041 Check_Fully_Declared (T, N);
3042 Freeze_Before (N, T);
3045 -- If the object was created by a constrained array definition, then
3046 -- set the link in both the anonymous base type and anonymous subtype
3047 -- that are built to represent the array type to point to the object.
3049 if Nkind (Object_Definition (Declaration_Node (Id))) =
3050 N_Constrained_Array_Definition
3052 Set_Related_Array_Object (T, Id);
3053 Set_Related_Array_Object (Base_Type (T), Id);
3056 -- Special checks for protected objects not at library level
3058 if Is_Protected_Type (T)
3059 and then not Is_Library_Level_Entity (Id)
3061 Check_Restriction (No_Local_Protected_Objects, Id);
3063 -- Protected objects with interrupt handlers must be at library level
3065 -- Ada 2005: this test is not needed (and the corresponding clause
3066 -- in the RM is removed) because accessibility checks are sufficient
3067 -- to make handlers not at the library level illegal.
3069 if Has_Interrupt_Handler (T)
3070 and then Ada_Version < Ada_2005
3073 ("interrupt object can only be declared at library level", Id);
3077 -- The actual subtype of the object is the nominal subtype, unless
3078 -- the nominal one is unconstrained and obtained from the expression.
3082 -- These checks should be performed before the initialization expression
3083 -- is considered, so that the Object_Definition node is still the same
3084 -- as in source code.
3086 -- In SPARK, the nominal subtype shall be given by a subtype mark and
3087 -- shall not be unconstrained. (The only exception to this is the
3088 -- admission of declarations of constants of type String.)
3091 Nkind_In (Object_Definition (N), N_Identifier, N_Expanded_Name)
3093 Check_SPARK_Restriction
3094 ("subtype mark required", Object_Definition (N));
3096 elsif Is_Array_Type (T)
3097 and then not Is_Constrained (T)
3098 and then T /= Standard_String
3100 Check_SPARK_Restriction
3101 ("subtype mark of constrained type expected",
3102 Object_Definition (N));
3105 -- There are no aliased objects in SPARK
3107 if Aliased_Present (N) then
3108 Check_SPARK_Restriction ("aliased object is not allowed", N);
3111 -- Process initialization expression if present and not in error
3113 if Present (E) and then E /= Error then
3115 -- Generate an error in case of CPP class-wide object initialization.
3116 -- Required because otherwise the expansion of the class-wide
3117 -- assignment would try to use 'size to initialize the object
3118 -- (primitive that is not available in CPP tagged types).
3120 if Is_Class_Wide_Type (Act_T)
3122 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3124 (Present (Full_View (Root_Type (Etype (Act_T))))
3126 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3129 ("predefined assignment not available for 'C'P'P tagged types",
3133 Mark_Coextensions (N, E);
3136 -- In case of errors detected in the analysis of the expression,
3137 -- decorate it with the expected type to avoid cascaded errors
3139 if No (Etype (E)) then
3143 -- If an initialization expression is present, then we set the
3144 -- Is_True_Constant flag. It will be reset if this is a variable
3145 -- and it is indeed modified.
3147 Set_Is_True_Constant (Id, True);
3149 -- If we are analyzing a constant declaration, set its completion
3150 -- flag after analyzing and resolving the expression.
3152 if Constant_Present (N) then
3153 Set_Has_Completion (Id);
3156 -- Set type and resolve (type may be overridden later on)
3161 -- If E is null and has been replaced by an N_Raise_Constraint_Error
3162 -- node (which was marked already-analyzed), we need to set the type
3163 -- to something other than Any_Access in order to keep gigi happy.
3165 if Etype (E) = Any_Access then
3169 -- If the object is an access to variable, the initialization
3170 -- expression cannot be an access to constant.
3172 if Is_Access_Type (T)
3173 and then not Is_Access_Constant (T)
3174 and then Is_Access_Type (Etype (E))
3175 and then Is_Access_Constant (Etype (E))
3178 ("access to variable cannot be initialized "
3179 & "with an access-to-constant expression", E);
3182 if not Assignment_OK (N) then
3183 Check_Initialization (T, E);
3186 Check_Unset_Reference (E);
3188 -- If this is a variable, then set current value. If this is a
3189 -- declared constant of a scalar type with a static expression,
3190 -- indicate that it is always valid.
3192 if not Constant_Present (N) then
3193 if Compile_Time_Known_Value (E) then
3194 Set_Current_Value (Id, E);
3197 elsif Is_Scalar_Type (T)
3198 and then Is_OK_Static_Expression (E)
3200 Set_Is_Known_Valid (Id);
3203 -- Deal with setting of null flags
3205 if Is_Access_Type (T) then
3206 if Known_Non_Null (E) then
3207 Set_Is_Known_Non_Null (Id, True);
3208 elsif Known_Null (E)
3209 and then not Can_Never_Be_Null (Id)
3211 Set_Is_Known_Null (Id, True);
3215 -- Check incorrect use of dynamically tagged expressions.
3217 if Is_Tagged_Type (T) then
3218 Check_Dynamically_Tagged_Expression
3224 Apply_Scalar_Range_Check (E, T);
3225 Apply_Static_Length_Check (E, T);
3227 if Nkind (Original_Node (N)) = N_Object_Declaration
3228 and then Comes_From_Source (Original_Node (N))
3230 -- Only call test if needed
3232 and then Restriction_Check_Required (SPARK)
3233 and then not Is_SPARK_Initialization_Expr (E)
3235 Check_SPARK_Restriction
3236 ("initialization expression is not appropriate", E);
3240 -- If the No_Streams restriction is set, check that the type of the
3241 -- object is not, and does not contain, any subtype derived from
3242 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
3243 -- Has_Stream just for efficiency reasons. There is no point in
3244 -- spending time on a Has_Stream check if the restriction is not set.
3246 if Restriction_Check_Required (No_Streams) then
3247 if Has_Stream (T) then
3248 Check_Restriction (No_Streams, N);
3252 -- Deal with predicate check before we start to do major rewriting.
3253 -- it is OK to initialize and then check the initialized value, since
3254 -- the object goes out of scope if we get a predicate failure. Note
3255 -- that we do this in the analyzer and not the expander because the
3256 -- analyzer does some substantial rewriting in some cases.
3258 -- We need a predicate check if the type has predicates, and if either
3259 -- there is an initializing expression, or for default initialization
3260 -- when we have at least one case of an explicit default initial value.
3262 if not Suppress_Assignment_Checks (N)
3263 and then Present (Predicate_Function (T))
3267 Is_Partially_Initialized_Type (T, Include_Implicit => False))
3270 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
3273 -- Case of unconstrained type
3275 if Is_Indefinite_Subtype (T) then
3277 -- In SPARK, a declaration of unconstrained type is allowed
3278 -- only for constants of type string.
3280 if Is_String_Type (T) and then not Constant_Present (N) then
3281 Check_SPARK_Restriction
3282 ("declaration of object of unconstrained type not allowed",
3286 -- Nothing to do in deferred constant case
3288 if Constant_Present (N) and then No (E) then
3291 -- Case of no initialization present
3294 if No_Initialization (N) then
3297 elsif Is_Class_Wide_Type (T) then
3299 ("initialization required in class-wide declaration ", N);
3303 ("unconstrained subtype not allowed (need initialization)",
3304 Object_Definition (N));
3306 if Is_Record_Type (T) and then Has_Discriminants (T) then
3308 ("\provide initial value or explicit discriminant values",
3309 Object_Definition (N));
3312 ("\or give default discriminant values for type&",
3313 Object_Definition (N), T);
3315 elsif Is_Array_Type (T) then
3317 ("\provide initial value or explicit array bounds",
3318 Object_Definition (N));
3322 -- Case of initialization present but in error. Set initial
3323 -- expression as absent (but do not make above complaints)
3325 elsif E = Error then
3326 Set_Expression (N, Empty);
3329 -- Case of initialization present
3332 -- Check restrictions in Ada 83
3334 if not Constant_Present (N) then
3336 -- Unconstrained variables not allowed in Ada 83 mode
3338 if Ada_Version = Ada_83
3339 and then Comes_From_Source (Object_Definition (N))
3342 ("(Ada 83) unconstrained variable not allowed",
3343 Object_Definition (N));
3347 -- Now we constrain the variable from the initializing expression
3349 -- If the expression is an aggregate, it has been expanded into
3350 -- individual assignments. Retrieve the actual type from the
3351 -- expanded construct.
3353 if Is_Array_Type (T)
3354 and then No_Initialization (N)
3355 and then Nkind (Original_Node (E)) = N_Aggregate
3359 -- In case of class-wide interface object declarations we delay
3360 -- the generation of the equivalent record type declarations until
3361 -- its expansion because there are cases in they are not required.
3363 elsif Is_Interface (T) then
3367 Expand_Subtype_From_Expr (N, T, Object_Definition (N), E);
3368 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
3371 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
3373 if Aliased_Present (N) then
3374 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3377 Freeze_Before (N, Act_T);
3378 Freeze_Before (N, T);
3381 elsif Is_Array_Type (T)
3382 and then No_Initialization (N)
3383 and then Nkind (Original_Node (E)) = N_Aggregate
3385 if not Is_Entity_Name (Object_Definition (N)) then
3387 Check_Compile_Time_Size (Act_T);
3389 if Aliased_Present (N) then
3390 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3394 -- When the given object definition and the aggregate are specified
3395 -- independently, and their lengths might differ do a length check.
3396 -- This cannot happen if the aggregate is of the form (others =>...)
3398 if not Is_Constrained (T) then
3401 elsif Nkind (E) = N_Raise_Constraint_Error then
3403 -- Aggregate is statically illegal. Place back in declaration
3405 Set_Expression (N, E);
3406 Set_No_Initialization (N, False);
3408 elsif T = Etype (E) then
3411 elsif Nkind (E) = N_Aggregate
3412 and then Present (Component_Associations (E))
3413 and then Present (Choices (First (Component_Associations (E))))
3414 and then Nkind (First
3415 (Choices (First (Component_Associations (E))))) = N_Others_Choice
3420 Apply_Length_Check (E, T);
3423 -- If the type is limited unconstrained with defaulted discriminants and
3424 -- there is no expression, then the object is constrained by the
3425 -- defaults, so it is worthwhile building the corresponding subtype.
3427 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
3428 and then not Is_Constrained (T)
3429 and then Has_Discriminants (T)
3432 Act_T := Build_Default_Subtype (T, N);
3434 -- Ada 2005: a limited object may be initialized by means of an
3435 -- aggregate. If the type has default discriminants it has an
3436 -- unconstrained nominal type, Its actual subtype will be obtained
3437 -- from the aggregate, and not from the default discriminants.
3442 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
3444 elsif Present (Underlying_Type (T))
3445 and then not Is_Constrained (Underlying_Type (T))
3446 and then Has_Discriminants (Underlying_Type (T))
3447 and then Nkind (E) = N_Function_Call
3448 and then Constant_Present (N)
3450 -- The back-end has problems with constants of a discriminated type
3451 -- with defaults, if the initial value is a function call. We
3452 -- generate an intermediate temporary for the result of the call.
3453 -- It is unclear why this should make it acceptable to gcc. ???
3455 Remove_Side_Effects (E);
3457 -- If this is a constant declaration of an unconstrained type and
3458 -- the initialization is an aggregate, we can use the subtype of the
3459 -- aggregate for the declared entity because it is immutable.
3461 elsif not Is_Constrained (T)
3462 and then Has_Discriminants (T)
3463 and then Constant_Present (N)
3464 and then not Has_Unchecked_Union (T)
3465 and then Nkind (E) = N_Aggregate
3470 -- Check No_Wide_Characters restriction
3472 Check_Wide_Character_Restriction (T, Object_Definition (N));
3474 -- Indicate this is not set in source. Certainly true for constants, and
3475 -- true for variables so far (will be reset for a variable if and when
3476 -- we encounter a modification in the source).
3478 Set_Never_Set_In_Source (Id, True);
3480 -- Now establish the proper kind and type of the object
3482 if Constant_Present (N) then
3483 Set_Ekind (Id, E_Constant);
3484 Set_Is_True_Constant (Id, True);
3487 Set_Ekind (Id, E_Variable);
3489 -- A variable is set as shared passive if it appears in a shared
3490 -- passive package, and is at the outer level. This is not done for
3491 -- entities generated during expansion, because those are always
3492 -- manipulated locally.
3494 if Is_Shared_Passive (Current_Scope)
3495 and then Is_Library_Level_Entity (Id)
3496 and then Comes_From_Source (Id)
3498 Set_Is_Shared_Passive (Id);
3499 Check_Shared_Var (Id, T, N);
3502 -- Set Has_Initial_Value if initializing expression present. Note
3503 -- that if there is no initializing expression, we leave the state
3504 -- of this flag unchanged (usually it will be False, but notably in
3505 -- the case of exception choice variables, it will already be true).
3508 Set_Has_Initial_Value (Id, True);
3512 -- Initialize alignment and size and capture alignment setting
3514 Init_Alignment (Id);
3516 Set_Optimize_Alignment_Flags (Id);
3518 -- Deal with aliased case
3520 if Aliased_Present (N) then
3521 Set_Is_Aliased (Id);
3523 -- If the object is aliased and the type is unconstrained with
3524 -- defaulted discriminants and there is no expression, then the
3525 -- object is constrained by the defaults, so it is worthwhile
3526 -- building the corresponding subtype.
3528 -- Ada 2005 (AI-363): If the aliased object is discriminated and
3529 -- unconstrained, then only establish an actual subtype if the
3530 -- nominal subtype is indefinite. In definite cases the object is
3531 -- unconstrained in Ada 2005.
3534 and then Is_Record_Type (T)
3535 and then not Is_Constrained (T)
3536 and then Has_Discriminants (T)
3537 and then (Ada_Version < Ada_2005 or else Is_Indefinite_Subtype (T))
3539 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
3543 -- Now we can set the type of the object
3545 Set_Etype (Id, Act_T);
3547 -- Deal with controlled types
3549 if Has_Controlled_Component (Etype (Id))
3550 or else Is_Controlled (Etype (Id))
3552 if not Is_Library_Level_Entity (Id) then
3553 Check_Restriction (No_Nested_Finalization, N);
3555 Validate_Controlled_Object (Id);
3558 -- Generate a warning when an initialization causes an obvious ABE
3559 -- violation. If the init expression is a simple aggregate there
3560 -- shouldn't be any initialize/adjust call generated. This will be
3561 -- true as soon as aggregates are built in place when possible.
3563 -- ??? at the moment we do not generate warnings for temporaries
3564 -- created for those aggregates although Program_Error might be
3565 -- generated if compiled with -gnato.
3567 if Is_Controlled (Etype (Id))
3568 and then Comes_From_Source (Id)
3571 BT : constant Entity_Id := Base_Type (Etype (Id));
3573 Implicit_Call : Entity_Id;
3574 pragma Warnings (Off, Implicit_Call);
3575 -- ??? what is this for (never referenced!)
3577 function Is_Aggr (N : Node_Id) return Boolean;
3578 -- Check that N is an aggregate
3584 function Is_Aggr (N : Node_Id) return Boolean is
3586 case Nkind (Original_Node (N)) is
3587 when N_Aggregate | N_Extension_Aggregate =>
3590 when N_Qualified_Expression |
3592 N_Unchecked_Type_Conversion =>
3593 return Is_Aggr (Expression (Original_Node (N)));
3601 -- If no underlying type, we already are in an error situation.
3602 -- Do not try to add a warning since we do not have access to
3605 if No (Underlying_Type (BT)) then
3606 Implicit_Call := Empty;
3608 -- A generic type does not have usable primitive operators.
3609 -- Initialization calls are built for instances.
3611 elsif Is_Generic_Type (BT) then
3612 Implicit_Call := Empty;
3614 -- If the init expression is not an aggregate, an adjust call
3615 -- will be generated
3617 elsif Present (E) and then not Is_Aggr (E) then
3618 Implicit_Call := Find_Prim_Op (BT, Name_Adjust);
3620 -- If no init expression and we are not in the deferred
3621 -- constant case, an Initialize call will be generated
3623 elsif No (E) and then not Constant_Present (N) then
3624 Implicit_Call := Find_Prim_Op (BT, Name_Initialize);
3627 Implicit_Call := Empty;
3633 if Has_Task (Etype (Id)) then
3634 Check_Restriction (No_Tasking, N);
3636 -- Deal with counting max tasks
3638 -- Nothing to do if inside a generic
3640 if Inside_A_Generic then
3643 -- If library level entity, then count tasks
3645 elsif Is_Library_Level_Entity (Id) then
3646 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
3648 -- If not library level entity, then indicate we don't know max
3649 -- tasks and also check task hierarchy restriction and blocking
3650 -- operation (since starting a task is definitely blocking!)
3653 Check_Restriction (Max_Tasks, N);
3654 Check_Restriction (No_Task_Hierarchy, N);
3655 Check_Potentially_Blocking_Operation (N);
3658 -- A rather specialized test. If we see two tasks being declared
3659 -- of the same type in the same object declaration, and the task
3660 -- has an entry with an address clause, we know that program error
3661 -- will be raised at run time since we can't have two tasks with
3662 -- entries at the same address.
3664 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
3669 E := First_Entity (Etype (Id));
3670 while Present (E) loop
3671 if Ekind (E) = E_Entry
3672 and then Present (Get_Attribute_Definition_Clause
3673 (E, Attribute_Address))
3676 ("?more than one task with same entry address", N);
3678 ("\?Program_Error will be raised at run time", N);
3680 Make_Raise_Program_Error (Loc,
3681 Reason => PE_Duplicated_Entry_Address));
3691 -- Some simple constant-propagation: if the expression is a constant
3692 -- string initialized with a literal, share the literal. This avoids
3696 and then Is_Entity_Name (E)
3697 and then Ekind (Entity (E)) = E_Constant
3698 and then Base_Type (Etype (E)) = Standard_String
3701 Val : constant Node_Id := Constant_Value (Entity (E));
3704 and then Nkind (Val) = N_String_Literal
3706 Rewrite (E, New_Copy (Val));
3711 -- Another optimization: if the nominal subtype is unconstrained and
3712 -- the expression is a function call that returns an unconstrained
3713 -- type, rewrite the declaration as a renaming of the result of the
3714 -- call. The exceptions below are cases where the copy is expected,
3715 -- either by the back end (Aliased case) or by the semantics, as for
3716 -- initializing controlled types or copying tags for classwide types.
3719 and then Nkind (E) = N_Explicit_Dereference
3720 and then Nkind (Original_Node (E)) = N_Function_Call
3721 and then not Is_Library_Level_Entity (Id)
3722 and then not Is_Constrained (Underlying_Type (T))
3723 and then not Is_Aliased (Id)
3724 and then not Is_Class_Wide_Type (T)
3725 and then not Is_Controlled (T)
3726 and then not Has_Controlled_Component (Base_Type (T))
3727 and then Expander_Active
3730 Make_Object_Renaming_Declaration (Loc,
3731 Defining_Identifier => Id,
3732 Access_Definition => Empty,
3733 Subtype_Mark => New_Occurrence_Of
3734 (Base_Type (Etype (Id)), Loc),
3737 Set_Renamed_Object (Id, E);
3739 -- Force generation of debugging information for the constant and for
3740 -- the renamed function call.
3742 Set_Debug_Info_Needed (Id);
3743 Set_Debug_Info_Needed (Entity (Prefix (E)));
3746 if Present (Prev_Entity)
3747 and then Is_Frozen (Prev_Entity)
3748 and then not Error_Posted (Id)
3750 Error_Msg_N ("full constant declaration appears too late", N);
3753 Check_Eliminated (Id);
3755 -- Deal with setting In_Private_Part flag if in private part
3757 if Ekind (Scope (Id)) = E_Package
3758 and then In_Private_Part (Scope (Id))
3760 Set_In_Private_Part (Id);
3763 -- Check for violation of No_Local_Timing_Events
3765 if Restriction_Check_Required (No_Local_Timing_Events)
3766 and then not Is_Library_Level_Entity (Id)
3767 and then Is_RTE (Etype (Id), RE_Timing_Event)
3769 Check_Restriction (No_Local_Timing_Events, N);
3773 if Has_Aspects (N) then
3774 Analyze_Aspect_Specifications (N, Id);
3776 end Analyze_Object_Declaration;
3778 ---------------------------
3779 -- Analyze_Others_Choice --
3780 ---------------------------
3782 -- Nothing to do for the others choice node itself, the semantic analysis
3783 -- of the others choice will occur as part of the processing of the parent
3785 procedure Analyze_Others_Choice (N : Node_Id) is
3786 pragma Warnings (Off, N);
3789 end Analyze_Others_Choice;
3791 -------------------------------------------
3792 -- Analyze_Private_Extension_Declaration --
3793 -------------------------------------------
3795 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
3796 T : constant Entity_Id := Defining_Identifier (N);
3797 Indic : constant Node_Id := Subtype_Indication (N);
3798 Parent_Type : Entity_Id;
3799 Parent_Base : Entity_Id;
3802 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
3804 if Is_Non_Empty_List (Interface_List (N)) then
3810 Intf := First (Interface_List (N));
3811 while Present (Intf) loop
3812 T := Find_Type_Of_Subtype_Indic (Intf);
3814 Diagnose_Interface (Intf, T);
3820 Generate_Definition (T);
3822 -- For other than Ada 2012, just enter the name in the current scope
3824 if Ada_Version < Ada_2012 then
3827 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
3828 -- case of private type that completes an incomplete type.
3835 Prev := Find_Type_Name (N);
3837 pragma Assert (Prev = T
3838 or else (Ekind (Prev) = E_Incomplete_Type
3839 and then Present (Full_View (Prev))
3840 and then Full_View (Prev) = T));
3844 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
3845 Parent_Base := Base_Type (Parent_Type);
3847 if Parent_Type = Any_Type
3848 or else Etype (Parent_Type) = Any_Type
3850 Set_Ekind (T, Ekind (Parent_Type));
3851 Set_Etype (T, Any_Type);
3854 elsif not Is_Tagged_Type (Parent_Type) then
3856 ("parent of type extension must be a tagged type ", Indic);
3859 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
3860 Error_Msg_N ("premature derivation of incomplete type", Indic);
3863 elsif Is_Concurrent_Type (Parent_Type) then
3865 ("parent type of a private extension cannot be "
3866 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
3868 Set_Etype (T, Any_Type);
3869 Set_Ekind (T, E_Limited_Private_Type);
3870 Set_Private_Dependents (T, New_Elmt_List);
3871 Set_Error_Posted (T);
3875 -- Perhaps the parent type should be changed to the class-wide type's
3876 -- specific type in this case to prevent cascading errors ???
3878 if Is_Class_Wide_Type (Parent_Type) then
3880 ("parent of type extension must not be a class-wide type", Indic);
3884 if (not Is_Package_Or_Generic_Package (Current_Scope)
3885 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
3886 or else In_Private_Part (Current_Scope)
3889 Error_Msg_N ("invalid context for private extension", N);
3892 -- Set common attributes
3894 Set_Is_Pure (T, Is_Pure (Current_Scope));
3895 Set_Scope (T, Current_Scope);
3896 Set_Ekind (T, E_Record_Type_With_Private);
3897 Init_Size_Align (T);
3899 Set_Etype (T, Parent_Base);
3900 Set_Has_Task (T, Has_Task (Parent_Base));
3902 Set_Convention (T, Convention (Parent_Type));
3903 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
3904 Set_Is_First_Subtype (T);
3905 Make_Class_Wide_Type (T);
3907 if Unknown_Discriminants_Present (N) then
3908 Set_Discriminant_Constraint (T, No_Elist);
3911 Build_Derived_Record_Type (N, Parent_Type, T);
3913 -- Propagate inherited invariant information. The new type has
3914 -- invariants, if the parent type has inheritable invariants,
3915 -- and these invariants can in turn be inherited.
3917 if Has_Inheritable_Invariants (Parent_Type) then
3918 Set_Has_Inheritable_Invariants (T);
3919 Set_Has_Invariants (T);
3922 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
3923 -- synchronized formal derived type.
3925 if Ada_Version >= Ada_2005
3926 and then Synchronized_Present (N)
3928 Set_Is_Limited_Record (T);
3930 -- Formal derived type case
3932 if Is_Generic_Type (T) then
3934 -- The parent must be a tagged limited type or a synchronized
3937 if (not Is_Tagged_Type (Parent_Type)
3938 or else not Is_Limited_Type (Parent_Type))
3940 (not Is_Interface (Parent_Type)
3941 or else not Is_Synchronized_Interface (Parent_Type))
3943 Error_Msg_NE ("parent type of & must be tagged limited " &
3944 "or synchronized", N, T);
3947 -- The progenitors (if any) must be limited or synchronized
3950 if Present (Interfaces (T)) then
3953 Iface_Elmt : Elmt_Id;
3956 Iface_Elmt := First_Elmt (Interfaces (T));
3957 while Present (Iface_Elmt) loop
3958 Iface := Node (Iface_Elmt);
3960 if not Is_Limited_Interface (Iface)
3961 and then not Is_Synchronized_Interface (Iface)
3963 Error_Msg_NE ("progenitor & must be limited " &
3964 "or synchronized", N, Iface);
3967 Next_Elmt (Iface_Elmt);
3972 -- Regular derived extension, the parent must be a limited or
3973 -- synchronized interface.
3976 if not Is_Interface (Parent_Type)
3977 or else (not Is_Limited_Interface (Parent_Type)
3979 not Is_Synchronized_Interface (Parent_Type))
3982 ("parent type of & must be limited interface", N, T);
3986 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
3987 -- extension with a synchronized parent must be explicitly declared
3988 -- synchronized, because the full view will be a synchronized type.
3989 -- This must be checked before the check for limited types below,
3990 -- to ensure that types declared limited are not allowed to extend
3991 -- synchronized interfaces.
3993 elsif Is_Interface (Parent_Type)
3994 and then Is_Synchronized_Interface (Parent_Type)
3995 and then not Synchronized_Present (N)
3998 ("private extension of& must be explicitly synchronized",
4001 elsif Limited_Present (N) then
4002 Set_Is_Limited_Record (T);
4004 if not Is_Limited_Type (Parent_Type)
4006 (not Is_Interface (Parent_Type)
4007 or else not Is_Limited_Interface (Parent_Type))
4009 Error_Msg_NE ("parent type& of limited extension must be limited",
4015 if Has_Aspects (N) then
4016 Analyze_Aspect_Specifications (N, T);
4018 end Analyze_Private_Extension_Declaration;
4020 ---------------------------------
4021 -- Analyze_Subtype_Declaration --
4022 ---------------------------------
4024 procedure Analyze_Subtype_Declaration
4026 Skip : Boolean := False)
4028 Id : constant Entity_Id := Defining_Identifier (N);
4030 R_Checks : Check_Result;
4033 Generate_Definition (Id);
4034 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4035 Init_Size_Align (Id);
4037 -- The following guard condition on Enter_Name is to handle cases where
4038 -- the defining identifier has already been entered into the scope but
4039 -- the declaration as a whole needs to be analyzed.
4041 -- This case in particular happens for derived enumeration types. The
4042 -- derived enumeration type is processed as an inserted enumeration type
4043 -- declaration followed by a rewritten subtype declaration. The defining
4044 -- identifier, however, is entered into the name scope very early in the
4045 -- processing of the original type declaration and therefore needs to be
4046 -- avoided here, when the created subtype declaration is analyzed. (See
4047 -- Build_Derived_Types)
4049 -- This also happens when the full view of a private type is derived
4050 -- type with constraints. In this case the entity has been introduced
4051 -- in the private declaration.
4054 or else (Present (Etype (Id))
4055 and then (Is_Private_Type (Etype (Id))
4056 or else Is_Task_Type (Etype (Id))
4057 or else Is_Rewrite_Substitution (N)))
4065 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4067 -- Class-wide equivalent types of records with unknown discriminants
4068 -- involve the generation of an itype which serves as the private view
4069 -- of a constrained record subtype. In such cases the base type of the
4070 -- current subtype we are processing is the private itype. Use the full
4071 -- of the private itype when decorating various attributes.
4074 and then Is_Private_Type (T)
4075 and then Present (Full_View (T))
4080 -- Inherit common attributes
4082 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4083 Set_Is_Volatile (Id, Is_Volatile (T));
4084 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4085 Set_Is_Atomic (Id, Is_Atomic (T));
4086 Set_Is_Ada_2005_Only (Id, Is_Ada_2005_Only (T));
4087 Set_Is_Ada_2012_Only (Id, Is_Ada_2012_Only (T));
4088 Set_Convention (Id, Convention (T));
4090 -- If ancestor has predicates then so does the subtype, and in addition
4091 -- we must delay the freeze to properly arrange predicate inheritance.
4093 -- The Ancestor_Type test is a big kludge, there seem to be cases in
4094 -- which T = ID, so the above tests and assignments do nothing???
4096 if Has_Predicates (T)
4097 or else (Present (Ancestor_Subtype (T))
4098 and then Has_Predicates (Ancestor_Subtype (T)))
4100 Set_Has_Predicates (Id);
4101 Set_Has_Delayed_Freeze (Id);
4104 -- Subtype of Boolean cannot have a constraint in SPARK
4106 if Is_Boolean_Type (T)
4107 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4109 Check_SPARK_Restriction
4110 ("subtype of Boolean cannot have constraint", N);
4113 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4115 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4121 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4122 One_Cstr := First (Constraints (Cstr));
4123 while Present (One_Cstr) loop
4125 -- Index or discriminant constraint in SPARK must be a
4129 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4131 Check_SPARK_Restriction
4132 ("subtype mark required", One_Cstr);
4134 -- String subtype must have a lower bound of 1 in SPARK.
4135 -- Note that we do not need to test for the non-static case
4136 -- here, since that was already taken care of in
4137 -- Process_Range_Expr_In_Decl.
4139 elsif Base_Type (T) = Standard_String then
4140 Get_Index_Bounds (One_Cstr, Low, High);
4142 if Is_OK_Static_Expression (Low)
4143 and then Expr_Value (Low) /= 1
4145 Check_SPARK_Restriction
4146 ("String subtype must have lower bound of 1", N);
4156 -- In the case where there is no constraint given in the subtype
4157 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4158 -- semantic attributes must be established here.
4160 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
4161 Set_Etype (Id, Base_Type (T));
4163 -- Subtype of unconstrained array without constraint is not allowed
4166 if Is_Array_Type (T)
4167 and then not Is_Constrained (T)
4169 Check_SPARK_Restriction
4170 ("subtype of unconstrained array must have constraint", N);
4175 Set_Ekind (Id, E_Array_Subtype);
4176 Copy_Array_Subtype_Attributes (Id, T);
4178 when Decimal_Fixed_Point_Kind =>
4179 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
4180 Set_Digits_Value (Id, Digits_Value (T));
4181 Set_Delta_Value (Id, Delta_Value (T));
4182 Set_Scale_Value (Id, Scale_Value (T));
4183 Set_Small_Value (Id, Small_Value (T));
4184 Set_Scalar_Range (Id, Scalar_Range (T));
4185 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
4186 Set_Is_Constrained (Id, Is_Constrained (T));
4187 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4188 Set_RM_Size (Id, RM_Size (T));
4190 when Enumeration_Kind =>
4191 Set_Ekind (Id, E_Enumeration_Subtype);
4192 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4193 Set_Scalar_Range (Id, Scalar_Range (T));
4194 Set_Is_Character_Type (Id, Is_Character_Type (T));
4195 Set_Is_Constrained (Id, Is_Constrained (T));
4196 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4197 Set_RM_Size (Id, RM_Size (T));
4199 when Ordinary_Fixed_Point_Kind =>
4200 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4201 Set_Scalar_Range (Id, Scalar_Range (T));
4202 Set_Small_Value (Id, Small_Value (T));
4203 Set_Delta_Value (Id, Delta_Value (T));
4204 Set_Is_Constrained (Id, Is_Constrained (T));
4205 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4206 Set_RM_Size (Id, RM_Size (T));
4209 Set_Ekind (Id, E_Floating_Point_Subtype);
4210 Set_Scalar_Range (Id, Scalar_Range (T));
4211 Set_Digits_Value (Id, Digits_Value (T));
4212 Set_Is_Constrained (Id, Is_Constrained (T));
4214 when Signed_Integer_Kind =>
4215 Set_Ekind (Id, E_Signed_Integer_Subtype);
4216 Set_Scalar_Range (Id, Scalar_Range (T));
4217 Set_Is_Constrained (Id, Is_Constrained (T));
4218 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4219 Set_RM_Size (Id, RM_Size (T));
4221 when Modular_Integer_Kind =>
4222 Set_Ekind (Id, E_Modular_Integer_Subtype);
4223 Set_Scalar_Range (Id, Scalar_Range (T));
4224 Set_Is_Constrained (Id, Is_Constrained (T));
4225 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4226 Set_RM_Size (Id, RM_Size (T));
4228 when Class_Wide_Kind =>
4229 Set_Ekind (Id, E_Class_Wide_Subtype);
4230 Set_First_Entity (Id, First_Entity (T));
4231 Set_Last_Entity (Id, Last_Entity (T));
4232 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4233 Set_Cloned_Subtype (Id, T);
4234 Set_Is_Tagged_Type (Id, True);
4235 Set_Has_Unknown_Discriminants
4238 if Ekind (T) = E_Class_Wide_Subtype then
4239 Set_Equivalent_Type (Id, Equivalent_Type (T));
4242 when E_Record_Type | E_Record_Subtype =>
4243 Set_Ekind (Id, E_Record_Subtype);
4245 if Ekind (T) = E_Record_Subtype
4246 and then Present (Cloned_Subtype (T))
4248 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
4250 Set_Cloned_Subtype (Id, T);
4253 Set_First_Entity (Id, First_Entity (T));
4254 Set_Last_Entity (Id, Last_Entity (T));
4255 Set_Has_Discriminants (Id, Has_Discriminants (T));
4256 Set_Is_Constrained (Id, Is_Constrained (T));
4257 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4258 Set_Has_Implicit_Dereference
4259 (Id, Has_Implicit_Dereference (T));
4260 Set_Has_Unknown_Discriminants
4261 (Id, Has_Unknown_Discriminants (T));
4263 if Has_Discriminants (T) then
4264 Set_Discriminant_Constraint
4265 (Id, Discriminant_Constraint (T));
4266 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4268 elsif Has_Unknown_Discriminants (Id) then
4269 Set_Discriminant_Constraint (Id, No_Elist);
4272 if Is_Tagged_Type (T) then
4273 Set_Is_Tagged_Type (Id);
4274 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4275 Set_Direct_Primitive_Operations
4276 (Id, Direct_Primitive_Operations (T));
4277 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4279 if Is_Interface (T) then
4280 Set_Is_Interface (Id);
4281 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
4285 when Private_Kind =>
4286 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4287 Set_Has_Discriminants (Id, Has_Discriminants (T));
4288 Set_Is_Constrained (Id, Is_Constrained (T));
4289 Set_First_Entity (Id, First_Entity (T));
4290 Set_Last_Entity (Id, Last_Entity (T));
4291 Set_Private_Dependents (Id, New_Elmt_List);
4292 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4293 Set_Has_Implicit_Dereference
4294 (Id, Has_Implicit_Dereference (T));
4295 Set_Has_Unknown_Discriminants
4296 (Id, Has_Unknown_Discriminants (T));
4297 Set_Known_To_Have_Preelab_Init
4298 (Id, Known_To_Have_Preelab_Init (T));
4300 if Is_Tagged_Type (T) then
4301 Set_Is_Tagged_Type (Id);
4302 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4303 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4304 Set_Direct_Primitive_Operations (Id,
4305 Direct_Primitive_Operations (T));
4308 -- In general the attributes of the subtype of a private type
4309 -- are the attributes of the partial view of parent. However,
4310 -- the full view may be a discriminated type, and the subtype
4311 -- must share the discriminant constraint to generate correct
4312 -- calls to initialization procedures.
4314 if Has_Discriminants (T) then
4315 Set_Discriminant_Constraint
4316 (Id, Discriminant_Constraint (T));
4317 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4319 elsif Present (Full_View (T))
4320 and then Has_Discriminants (Full_View (T))
4322 Set_Discriminant_Constraint
4323 (Id, Discriminant_Constraint (Full_View (T)));
4324 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4326 -- This would seem semantically correct, but apparently
4327 -- confuses the back-end. To be explained and checked with
4328 -- current version ???
4330 -- Set_Has_Discriminants (Id);
4333 Prepare_Private_Subtype_Completion (Id, N);
4336 Set_Ekind (Id, E_Access_Subtype);
4337 Set_Is_Constrained (Id, Is_Constrained (T));
4338 Set_Is_Access_Constant
4339 (Id, Is_Access_Constant (T));
4340 Set_Directly_Designated_Type
4341 (Id, Designated_Type (T));
4342 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
4344 -- A Pure library_item must not contain the declaration of a
4345 -- named access type, except within a subprogram, generic
4346 -- subprogram, task unit, or protected unit, or if it has
4347 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
4349 if Comes_From_Source (Id)
4350 and then In_Pure_Unit
4351 and then not In_Subprogram_Task_Protected_Unit
4352 and then not No_Pool_Assigned (Id)
4355 ("named access types not allowed in pure unit", N);
4358 when Concurrent_Kind =>
4359 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4360 Set_Corresponding_Record_Type (Id,
4361 Corresponding_Record_Type (T));
4362 Set_First_Entity (Id, First_Entity (T));
4363 Set_First_Private_Entity (Id, First_Private_Entity (T));
4364 Set_Has_Discriminants (Id, Has_Discriminants (T));
4365 Set_Is_Constrained (Id, Is_Constrained (T));
4366 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4367 Set_Last_Entity (Id, Last_Entity (T));
4369 if Has_Discriminants (T) then
4370 Set_Discriminant_Constraint (Id,
4371 Discriminant_Constraint (T));
4372 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4375 when E_Incomplete_Type =>
4376 if Ada_Version >= Ada_2005 then
4377 Set_Ekind (Id, E_Incomplete_Subtype);
4379 -- Ada 2005 (AI-412): Decorate an incomplete subtype
4380 -- of an incomplete type visible through a limited
4383 if From_With_Type (T)
4384 and then Present (Non_Limited_View (T))
4386 Set_From_With_Type (Id);
4387 Set_Non_Limited_View (Id, Non_Limited_View (T));
4389 -- Ada 2005 (AI-412): Add the regular incomplete subtype
4390 -- to the private dependents of the original incomplete
4391 -- type for future transformation.
4394 Append_Elmt (Id, Private_Dependents (T));
4397 -- If the subtype name denotes an incomplete type an error
4398 -- was already reported by Process_Subtype.
4401 Set_Etype (Id, Any_Type);
4405 raise Program_Error;
4409 if Etype (Id) = Any_Type then
4413 -- Some common processing on all types
4415 Set_Size_Info (Id, T);
4416 Set_First_Rep_Item (Id, First_Rep_Item (T));
4420 Set_Is_Immediately_Visible (Id, True);
4421 Set_Depends_On_Private (Id, Has_Private_Component (T));
4422 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
4424 if Is_Interface (T) then
4425 Set_Is_Interface (Id);
4428 if Present (Generic_Parent_Type (N))
4431 (Parent (Generic_Parent_Type (N))) /= N_Formal_Type_Declaration
4433 (Formal_Type_Definition (Parent (Generic_Parent_Type (N))))
4434 /= N_Formal_Private_Type_Definition)
4436 if Is_Tagged_Type (Id) then
4438 -- If this is a generic actual subtype for a synchronized type,
4439 -- the primitive operations are those of the corresponding record
4440 -- for which there is a separate subtype declaration.
4442 if Is_Concurrent_Type (Id) then
4444 elsif Is_Class_Wide_Type (Id) then
4445 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
4447 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
4450 elsif Scope (Etype (Id)) /= Standard_Standard then
4451 Derive_Subprograms (Generic_Parent_Type (N), Id);
4455 if Is_Private_Type (T)
4456 and then Present (Full_View (T))
4458 Conditional_Delay (Id, Full_View (T));
4460 -- The subtypes of components or subcomponents of protected types
4461 -- do not need freeze nodes, which would otherwise appear in the
4462 -- wrong scope (before the freeze node for the protected type). The
4463 -- proper subtypes are those of the subcomponents of the corresponding
4466 elsif Ekind (Scope (Id)) /= E_Protected_Type
4467 and then Present (Scope (Scope (Id))) -- error defense!
4468 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
4470 Conditional_Delay (Id, T);
4473 -- Check that Constraint_Error is raised for a scalar subtype indication
4474 -- when the lower or upper bound of a non-null range lies outside the
4475 -- range of the type mark.
4477 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4478 if Is_Scalar_Type (Etype (Id))
4479 and then Scalar_Range (Id) /=
4480 Scalar_Range (Etype (Subtype_Mark
4481 (Subtype_Indication (N))))
4485 Etype (Subtype_Mark (Subtype_Indication (N))));
4487 -- In the array case, check compatibility for each index
4489 elsif Is_Array_Type (Etype (Id))
4490 and then Present (First_Index (Id))
4492 -- This really should be a subprogram that finds the indications
4496 Subt_Index : Node_Id := First_Index (Id);
4497 Target_Index : Node_Id :=
4499 (Subtype_Mark (Subtype_Indication (N))));
4500 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
4503 while Present (Subt_Index) loop
4504 if ((Nkind (Subt_Index) = N_Identifier
4505 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
4506 or else Nkind (Subt_Index) = N_Subtype_Indication)
4508 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
4511 Target_Typ : constant Entity_Id :=
4512 Etype (Target_Index);
4516 (Scalar_Range (Etype (Subt_Index)),
4519 Defining_Identifier (N));
4521 -- Reset Has_Dynamic_Range_Check on the subtype to
4522 -- prevent elision of the index check due to a dynamic
4523 -- check generated for a preceding index (needed since
4524 -- Insert_Range_Checks tries to avoid generating
4525 -- redundant checks on a given declaration).
4527 Set_Has_Dynamic_Range_Check (N, False);
4533 Sloc (Defining_Identifier (N)));
4535 -- Record whether this index involved a dynamic check
4538 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
4542 Next_Index (Subt_Index);
4543 Next_Index (Target_Index);
4546 -- Finally, mark whether the subtype involves dynamic checks
4548 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
4553 -- Make sure that generic actual types are properly frozen. The subtype
4554 -- is marked as a generic actual type when the enclosing instance is
4555 -- analyzed, so here we identify the subtype from the tree structure.
4558 and then Is_Generic_Actual_Type (Id)
4559 and then In_Instance
4560 and then not Comes_From_Source (N)
4561 and then Nkind (Subtype_Indication (N)) /= N_Subtype_Indication
4562 and then Is_Frozen (T)
4564 Freeze_Before (N, Id);
4567 Set_Optimize_Alignment_Flags (Id);
4568 Check_Eliminated (Id);
4571 if Has_Aspects (N) then
4572 Analyze_Aspect_Specifications (N, Id);
4574 end Analyze_Subtype_Declaration;
4576 --------------------------------
4577 -- Analyze_Subtype_Indication --
4578 --------------------------------
4580 procedure Analyze_Subtype_Indication (N : Node_Id) is
4581 T : constant Entity_Id := Subtype_Mark (N);
4582 R : constant Node_Id := Range_Expression (Constraint (N));
4589 Set_Etype (N, Etype (R));
4590 Resolve (R, Entity (T));
4592 Set_Error_Posted (R);
4593 Set_Error_Posted (T);
4595 end Analyze_Subtype_Indication;
4597 --------------------------
4598 -- Analyze_Variant_Part --
4599 --------------------------
4601 procedure Analyze_Variant_Part (N : Node_Id) is
4603 procedure Non_Static_Choice_Error (Choice : Node_Id);
4604 -- Error routine invoked by the generic instantiation below when the
4605 -- variant part has a non static choice.
4607 procedure Process_Declarations (Variant : Node_Id);
4608 -- Analyzes all the declarations associated with a Variant. Needed by
4609 -- the generic instantiation below.
4611 package Variant_Choices_Processing is new
4612 Generic_Choices_Processing
4613 (Get_Alternatives => Variants,
4614 Get_Choices => Discrete_Choices,
4615 Process_Empty_Choice => No_OP,
4616 Process_Non_Static_Choice => Non_Static_Choice_Error,
4617 Process_Associated_Node => Process_Declarations);
4618 use Variant_Choices_Processing;
4619 -- Instantiation of the generic choice processing package
4621 -----------------------------
4622 -- Non_Static_Choice_Error --
4623 -----------------------------
4625 procedure Non_Static_Choice_Error (Choice : Node_Id) is
4627 Flag_Non_Static_Expr
4628 ("choice given in variant part is not static!", Choice);
4629 end Non_Static_Choice_Error;
4631 --------------------------
4632 -- Process_Declarations --
4633 --------------------------
4635 procedure Process_Declarations (Variant : Node_Id) is
4637 if not Null_Present (Component_List (Variant)) then
4638 Analyze_Declarations (Component_Items (Component_List (Variant)));
4640 if Present (Variant_Part (Component_List (Variant))) then
4641 Analyze (Variant_Part (Component_List (Variant)));
4644 end Process_Declarations;
4648 Discr_Name : Node_Id;
4649 Discr_Type : Entity_Id;
4651 Dont_Care : Boolean;
4652 Others_Present : Boolean := False;
4654 pragma Warnings (Off, Dont_Care);
4655 pragma Warnings (Off, Others_Present);
4656 -- We don't care about the assigned values of any of these
4658 -- Start of processing for Analyze_Variant_Part
4661 Discr_Name := Name (N);
4662 Analyze (Discr_Name);
4664 -- If Discr_Name bad, get out (prevent cascaded errors)
4666 if Etype (Discr_Name) = Any_Type then
4670 -- Check invalid discriminant in variant part
4672 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
4673 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
4676 Discr_Type := Etype (Entity (Discr_Name));
4678 if not Is_Discrete_Type (Discr_Type) then
4680 ("discriminant in a variant part must be of a discrete type",
4685 -- Call the instantiated Analyze_Choices which does the rest of the work
4687 Analyze_Choices (N, Discr_Type, Dont_Care, Others_Present);
4688 end Analyze_Variant_Part;
4690 ----------------------------
4691 -- Array_Type_Declaration --
4692 ----------------------------
4694 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
4695 Component_Def : constant Node_Id := Component_Definition (Def);
4696 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
4697 Element_Type : Entity_Id;
4698 Implicit_Base : Entity_Id;
4700 Related_Id : Entity_Id := Empty;
4702 P : constant Node_Id := Parent (Def);
4706 if Nkind (Def) = N_Constrained_Array_Definition then
4707 Index := First (Discrete_Subtype_Definitions (Def));
4709 Index := First (Subtype_Marks (Def));
4712 -- Find proper names for the implicit types which may be public. In case
4713 -- of anonymous arrays we use the name of the first object of that type
4717 Related_Id := Defining_Identifier (P);
4723 while Present (Index) loop
4726 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
4727 Check_SPARK_Restriction ("subtype mark required", Index);
4730 -- Add a subtype declaration for each index of private array type
4731 -- declaration whose etype is also private. For example:
4734 -- type Index is private;
4736 -- type Table is array (Index) of ...
4739 -- This is currently required by the expander for the internally
4740 -- generated equality subprogram of records with variant parts in
4741 -- which the etype of some component is such private type.
4743 if Ekind (Current_Scope) = E_Package
4744 and then In_Private_Part (Current_Scope)
4745 and then Has_Private_Declaration (Etype (Index))
4748 Loc : constant Source_Ptr := Sloc (Def);
4753 New_E := Make_Temporary (Loc, 'T');
4754 Set_Is_Internal (New_E);
4757 Make_Subtype_Declaration (Loc,
4758 Defining_Identifier => New_E,
4759 Subtype_Indication =>
4760 New_Occurrence_Of (Etype (Index), Loc));
4762 Insert_Before (Parent (Def), Decl);
4764 Set_Etype (Index, New_E);
4766 -- If the index is a range the Entity attribute is not
4767 -- available. Example:
4770 -- type T is private;
4772 -- type T is new Natural;
4773 -- Table : array (T(1) .. T(10)) of Boolean;
4776 if Nkind (Index) /= N_Range then
4777 Set_Entity (Index, New_E);
4782 Make_Index (Index, P, Related_Id, Nb_Index);
4784 -- Check error of subtype with predicate for index type
4786 Bad_Predicated_Subtype_Use
4787 ("subtype& has predicate, not allowed as index subtype",
4788 Index, Etype (Index));
4790 -- Move to next index
4793 Nb_Index := Nb_Index + 1;
4796 -- Process subtype indication if one is present
4798 if Present (Component_Typ) then
4799 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
4801 Set_Etype (Component_Typ, Element_Type);
4803 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
4804 Check_SPARK_Restriction ("subtype mark required", Component_Typ);
4807 -- Ada 2005 (AI-230): Access Definition case
4809 else pragma Assert (Present (Access_Definition (Component_Def)));
4811 -- Indicate that the anonymous access type is created by the
4812 -- array type declaration.
4814 Element_Type := Access_Definition
4816 N => Access_Definition (Component_Def));
4817 Set_Is_Local_Anonymous_Access (Element_Type);
4819 -- Propagate the parent. This field is needed if we have to generate
4820 -- the master_id associated with an anonymous access to task type
4821 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
4823 Set_Parent (Element_Type, Parent (T));
4825 -- Ada 2005 (AI-230): In case of components that are anonymous access
4826 -- types the level of accessibility depends on the enclosing type
4829 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
4831 -- Ada 2005 (AI-254)
4834 CD : constant Node_Id :=
4835 Access_To_Subprogram_Definition
4836 (Access_Definition (Component_Def));
4838 if Present (CD) and then Protected_Present (CD) then
4840 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
4845 -- Constrained array case
4848 T := Create_Itype (E_Void, P, Related_Id, 'T');
4851 if Nkind (Def) = N_Constrained_Array_Definition then
4853 -- Establish Implicit_Base as unconstrained base type
4855 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
4857 Set_Etype (Implicit_Base, Implicit_Base);
4858 Set_Scope (Implicit_Base, Current_Scope);
4859 Set_Has_Delayed_Freeze (Implicit_Base);
4861 -- The constrained array type is a subtype of the unconstrained one
4863 Set_Ekind (T, E_Array_Subtype);
4864 Init_Size_Align (T);
4865 Set_Etype (T, Implicit_Base);
4866 Set_Scope (T, Current_Scope);
4867 Set_Is_Constrained (T, True);
4868 Set_First_Index (T, First (Discrete_Subtype_Definitions (Def)));
4869 Set_Has_Delayed_Freeze (T);
4871 -- Complete setup of implicit base type
4873 Set_First_Index (Implicit_Base, First_Index (T));
4874 Set_Component_Type (Implicit_Base, Element_Type);
4875 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
4876 Set_Component_Size (Implicit_Base, Uint_0);
4877 Set_Packed_Array_Type (Implicit_Base, Empty);
4878 Set_Has_Controlled_Component
4879 (Implicit_Base, Has_Controlled_Component
4881 or else Is_Controlled
4883 Set_Finalize_Storage_Only
4884 (Implicit_Base, Finalize_Storage_Only
4887 -- Unconstrained array case
4890 Set_Ekind (T, E_Array_Type);
4891 Init_Size_Align (T);
4893 Set_Scope (T, Current_Scope);
4894 Set_Component_Size (T, Uint_0);
4895 Set_Is_Constrained (T, False);
4896 Set_First_Index (T, First (Subtype_Marks (Def)));
4897 Set_Has_Delayed_Freeze (T, True);
4898 Set_Has_Task (T, Has_Task (Element_Type));
4899 Set_Has_Controlled_Component (T, Has_Controlled_Component
4902 Is_Controlled (Element_Type));
4903 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
4907 -- Common attributes for both cases
4909 Set_Component_Type (Base_Type (T), Element_Type);
4910 Set_Packed_Array_Type (T, Empty);
4912 if Aliased_Present (Component_Definition (Def)) then
4913 Check_SPARK_Restriction
4914 ("aliased is not allowed", Component_Definition (Def));
4915 Set_Has_Aliased_Components (Etype (T));
4918 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
4919 -- array type to ensure that objects of this type are initialized.
4921 if Ada_Version >= Ada_2005
4922 and then Can_Never_Be_Null (Element_Type)
4924 Set_Can_Never_Be_Null (T);
4926 if Null_Exclusion_Present (Component_Definition (Def))
4928 -- No need to check itypes because in their case this check was
4929 -- done at their point of creation
4931 and then not Is_Itype (Element_Type)
4934 ("`NOT NULL` not allowed (null already excluded)",
4935 Subtype_Indication (Component_Definition (Def)));
4939 Priv := Private_Component (Element_Type);
4941 if Present (Priv) then
4943 -- Check for circular definitions
4945 if Priv = Any_Type then
4946 Set_Component_Type (Etype (T), Any_Type);
4948 -- There is a gap in the visibility of operations on the composite
4949 -- type only if the component type is defined in a different scope.
4951 elsif Scope (Priv) = Current_Scope then
4954 elsif Is_Limited_Type (Priv) then
4955 Set_Is_Limited_Composite (Etype (T));
4956 Set_Is_Limited_Composite (T);
4958 Set_Is_Private_Composite (Etype (T));
4959 Set_Is_Private_Composite (T);
4963 -- A syntax error in the declaration itself may lead to an empty index
4964 -- list, in which case do a minimal patch.
4966 if No (First_Index (T)) then
4967 Error_Msg_N ("missing index definition in array type declaration", T);
4970 Indexes : constant List_Id :=
4971 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
4973 Set_Discrete_Subtype_Definitions (Def, Indexes);
4974 Set_First_Index (T, First (Indexes));
4979 -- Create a concatenation operator for the new type. Internal array
4980 -- types created for packed entities do not need such, they are
4981 -- compatible with the user-defined type.
4983 if Number_Dimensions (T) = 1
4984 and then not Is_Packed_Array_Type (T)
4986 New_Concatenation_Op (T);
4989 -- In the case of an unconstrained array the parser has already verified
4990 -- that all the indexes are unconstrained but we still need to make sure
4991 -- that the element type is constrained.
4993 if Is_Indefinite_Subtype (Element_Type) then
4995 ("unconstrained element type in array declaration",
4996 Subtype_Indication (Component_Def));
4998 elsif Is_Abstract_Type (Element_Type) then
5000 ("the type of a component cannot be abstract",
5001 Subtype_Indication (Component_Def));
5003 end Array_Type_Declaration;
5005 ------------------------------------------------------
5006 -- Replace_Anonymous_Access_To_Protected_Subprogram --
5007 ------------------------------------------------------
5009 function Replace_Anonymous_Access_To_Protected_Subprogram
5010 (N : Node_Id) return Entity_Id
5012 Loc : constant Source_Ptr := Sloc (N);
5014 Curr_Scope : constant Scope_Stack_Entry :=
5015 Scope_Stack.Table (Scope_Stack.Last);
5017 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
5024 Set_Is_Internal (Anon);
5027 when N_Component_Declaration |
5028 N_Unconstrained_Array_Definition |
5029 N_Constrained_Array_Definition =>
5030 Comp := Component_Definition (N);
5031 Acc := Access_Definition (Comp);
5033 when N_Discriminant_Specification =>
5034 Comp := Discriminant_Type (N);
5037 when N_Parameter_Specification =>
5038 Comp := Parameter_Type (N);
5041 when N_Access_Function_Definition =>
5042 Comp := Result_Definition (N);
5045 when N_Object_Declaration =>
5046 Comp := Object_Definition (N);
5049 when N_Function_Specification =>
5050 Comp := Result_Definition (N);
5054 raise Program_Error;
5057 Decl := Make_Full_Type_Declaration (Loc,
5058 Defining_Identifier => Anon,
5060 Copy_Separate_Tree (Access_To_Subprogram_Definition (Acc)));
5062 Mark_Rewrite_Insertion (Decl);
5064 -- Insert the new declaration in the nearest enclosing scope. If the
5065 -- node is a body and N is its return type, the declaration belongs in
5066 -- the enclosing scope.
5070 if Nkind (P) = N_Subprogram_Body
5071 and then Nkind (N) = N_Function_Specification
5076 while Present (P) and then not Has_Declarations (P) loop
5080 pragma Assert (Present (P));
5082 if Nkind (P) = N_Package_Specification then
5083 Prepend (Decl, Visible_Declarations (P));
5085 Prepend (Decl, Declarations (P));
5088 -- Replace the anonymous type with an occurrence of the new declaration.
5089 -- In all cases the rewritten node does not have the null-exclusion
5090 -- attribute because (if present) it was already inherited by the
5091 -- anonymous entity (Anon). Thus, in case of components we do not
5092 -- inherit this attribute.
5094 if Nkind (N) = N_Parameter_Specification then
5095 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5096 Set_Etype (Defining_Identifier (N), Anon);
5097 Set_Null_Exclusion_Present (N, False);
5099 elsif Nkind (N) = N_Object_Declaration then
5100 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5101 Set_Etype (Defining_Identifier (N), Anon);
5103 elsif Nkind (N) = N_Access_Function_Definition then
5104 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5106 elsif Nkind (N) = N_Function_Specification then
5107 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5108 Set_Etype (Defining_Unit_Name (N), Anon);
5112 Make_Component_Definition (Loc,
5113 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
5116 Mark_Rewrite_Insertion (Comp);
5118 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition) then
5122 -- Temporarily remove the current scope (record or subprogram) from
5123 -- the stack to add the new declarations to the enclosing scope.
5125 Scope_Stack.Decrement_Last;
5127 Set_Is_Itype (Anon);
5128 Scope_Stack.Append (Curr_Scope);
5131 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
5132 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
5134 end Replace_Anonymous_Access_To_Protected_Subprogram;
5136 -------------------------------
5137 -- Build_Derived_Access_Type --
5138 -------------------------------
5140 procedure Build_Derived_Access_Type
5142 Parent_Type : Entity_Id;
5143 Derived_Type : Entity_Id)
5145 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
5147 Desig_Type : Entity_Id;
5149 Discr_Con_Elist : Elist_Id;
5150 Discr_Con_El : Elmt_Id;
5154 -- Set the designated type so it is available in case this is an access
5155 -- to a self-referential type, e.g. a standard list type with a next
5156 -- pointer. Will be reset after subtype is built.
5158 Set_Directly_Designated_Type
5159 (Derived_Type, Designated_Type (Parent_Type));
5161 Subt := Process_Subtype (S, N);
5163 if Nkind (S) /= N_Subtype_Indication
5164 and then Subt /= Base_Type (Subt)
5166 Set_Ekind (Derived_Type, E_Access_Subtype);
5169 if Ekind (Derived_Type) = E_Access_Subtype then
5171 Pbase : constant Entity_Id := Base_Type (Parent_Type);
5172 Ibase : constant Entity_Id :=
5173 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
5174 Svg_Chars : constant Name_Id := Chars (Ibase);
5175 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
5178 Copy_Node (Pbase, Ibase);
5180 Set_Chars (Ibase, Svg_Chars);
5181 Set_Next_Entity (Ibase, Svg_Next_E);
5182 Set_Sloc (Ibase, Sloc (Derived_Type));
5183 Set_Scope (Ibase, Scope (Derived_Type));
5184 Set_Freeze_Node (Ibase, Empty);
5185 Set_Is_Frozen (Ibase, False);
5186 Set_Comes_From_Source (Ibase, False);
5187 Set_Is_First_Subtype (Ibase, False);
5189 Set_Etype (Ibase, Pbase);
5190 Set_Etype (Derived_Type, Ibase);
5194 Set_Directly_Designated_Type
5195 (Derived_Type, Designated_Type (Subt));
5197 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
5198 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
5199 Set_Size_Info (Derived_Type, Parent_Type);
5200 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
5201 Set_Depends_On_Private (Derived_Type,
5202 Has_Private_Component (Derived_Type));
5203 Conditional_Delay (Derived_Type, Subt);
5205 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
5206 -- that it is not redundant.
5208 if Null_Exclusion_Present (Type_Definition (N)) then
5209 Set_Can_Never_Be_Null (Derived_Type);
5211 if Can_Never_Be_Null (Parent_Type)
5215 ("`NOT NULL` not allowed (& already excludes null)",
5219 elsif Can_Never_Be_Null (Parent_Type) then
5220 Set_Can_Never_Be_Null (Derived_Type);
5223 -- Note: we do not copy the Storage_Size_Variable, since we always go to
5224 -- the root type for this information.
5226 -- Apply range checks to discriminants for derived record case
5227 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
5229 Desig_Type := Designated_Type (Derived_Type);
5230 if Is_Composite_Type (Desig_Type)
5231 and then (not Is_Array_Type (Desig_Type))
5232 and then Has_Discriminants (Desig_Type)
5233 and then Base_Type (Desig_Type) /= Desig_Type
5235 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
5236 Discr_Con_El := First_Elmt (Discr_Con_Elist);
5238 Discr := First_Discriminant (Base_Type (Desig_Type));
5239 while Present (Discr_Con_El) loop
5240 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
5241 Next_Elmt (Discr_Con_El);
5242 Next_Discriminant (Discr);
5245 end Build_Derived_Access_Type;
5247 ------------------------------
5248 -- Build_Derived_Array_Type --
5249 ------------------------------
5251 procedure Build_Derived_Array_Type
5253 Parent_Type : Entity_Id;
5254 Derived_Type : Entity_Id)
5256 Loc : constant Source_Ptr := Sloc (N);
5257 Tdef : constant Node_Id := Type_Definition (N);
5258 Indic : constant Node_Id := Subtype_Indication (Tdef);
5259 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5260 Implicit_Base : Entity_Id;
5261 New_Indic : Node_Id;
5263 procedure Make_Implicit_Base;
5264 -- If the parent subtype is constrained, the derived type is a subtype
5265 -- of an implicit base type derived from the parent base.
5267 ------------------------
5268 -- Make_Implicit_Base --
5269 ------------------------
5271 procedure Make_Implicit_Base is
5274 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5276 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5277 Set_Etype (Implicit_Base, Parent_Base);
5279 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
5280 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
5282 Set_Has_Delayed_Freeze (Implicit_Base, True);
5283 end Make_Implicit_Base;
5285 -- Start of processing for Build_Derived_Array_Type
5288 if not Is_Constrained (Parent_Type) then
5289 if Nkind (Indic) /= N_Subtype_Indication then
5290 Set_Ekind (Derived_Type, E_Array_Type);
5292 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5293 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
5295 Set_Has_Delayed_Freeze (Derived_Type, True);
5299 Set_Etype (Derived_Type, Implicit_Base);
5302 Make_Subtype_Declaration (Loc,
5303 Defining_Identifier => Derived_Type,
5304 Subtype_Indication =>
5305 Make_Subtype_Indication (Loc,
5306 Subtype_Mark => New_Reference_To (Implicit_Base, Loc),
5307 Constraint => Constraint (Indic)));
5309 Rewrite (N, New_Indic);
5314 if Nkind (Indic) /= N_Subtype_Indication then
5317 Set_Ekind (Derived_Type, Ekind (Parent_Type));
5318 Set_Etype (Derived_Type, Implicit_Base);
5319 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5322 Error_Msg_N ("illegal constraint on constrained type", Indic);
5326 -- If parent type is not a derived type itself, and is declared in
5327 -- closed scope (e.g. a subprogram), then we must explicitly introduce
5328 -- the new type's concatenation operator since Derive_Subprograms
5329 -- will not inherit the parent's operator. If the parent type is
5330 -- unconstrained, the operator is of the unconstrained base type.
5332 if Number_Dimensions (Parent_Type) = 1
5333 and then not Is_Limited_Type (Parent_Type)
5334 and then not Is_Derived_Type (Parent_Type)
5335 and then not Is_Package_Or_Generic_Package
5336 (Scope (Base_Type (Parent_Type)))
5338 if not Is_Constrained (Parent_Type)
5339 and then Is_Constrained (Derived_Type)
5341 New_Concatenation_Op (Implicit_Base);
5343 New_Concatenation_Op (Derived_Type);
5346 end Build_Derived_Array_Type;
5348 -----------------------------------
5349 -- Build_Derived_Concurrent_Type --
5350 -----------------------------------
5352 procedure Build_Derived_Concurrent_Type
5354 Parent_Type : Entity_Id;
5355 Derived_Type : Entity_Id)
5357 Loc : constant Source_Ptr := Sloc (N);
5359 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
5360 Corr_Decl : Node_Id;
5361 Corr_Decl_Needed : Boolean;
5362 -- If the derived type has fewer discriminants than its parent, the
5363 -- corresponding record is also a derived type, in order to account for
5364 -- the bound discriminants. We create a full type declaration for it in
5367 Constraint_Present : constant Boolean :=
5368 Nkind (Subtype_Indication (Type_Definition (N))) =
5369 N_Subtype_Indication;
5371 D_Constraint : Node_Id;
5372 New_Constraint : Elist_Id;
5373 Old_Disc : Entity_Id;
5374 New_Disc : Entity_Id;
5378 Set_Stored_Constraint (Derived_Type, No_Elist);
5379 Corr_Decl_Needed := False;
5382 if Present (Discriminant_Specifications (N))
5383 and then Constraint_Present
5385 Old_Disc := First_Discriminant (Parent_Type);
5386 New_Disc := First (Discriminant_Specifications (N));
5387 while Present (New_Disc) and then Present (Old_Disc) loop
5388 Next_Discriminant (Old_Disc);
5393 if Present (Old_Disc) and then Expander_Active then
5395 -- The new type has fewer discriminants, so we need to create a new
5396 -- corresponding record, which is derived from the corresponding
5397 -- record of the parent, and has a stored constraint that captures
5398 -- the values of the discriminant constraints. The corresponding
5399 -- record is needed only if expander is active and code generation is
5402 -- The type declaration for the derived corresponding record has the
5403 -- same discriminant part and constraints as the current declaration.
5404 -- Copy the unanalyzed tree to build declaration.
5406 Corr_Decl_Needed := True;
5407 New_N := Copy_Separate_Tree (N);
5410 Make_Full_Type_Declaration (Loc,
5411 Defining_Identifier => Corr_Record,
5412 Discriminant_Specifications =>
5413 Discriminant_Specifications (New_N),
5415 Make_Derived_Type_Definition (Loc,
5416 Subtype_Indication =>
5417 Make_Subtype_Indication (Loc,
5420 (Corresponding_Record_Type (Parent_Type), Loc),
5423 (Subtype_Indication (Type_Definition (New_N))))));
5426 -- Copy Storage_Size and Relative_Deadline variables if task case
5428 if Is_Task_Type (Parent_Type) then
5429 Set_Storage_Size_Variable (Derived_Type,
5430 Storage_Size_Variable (Parent_Type));
5431 Set_Relative_Deadline_Variable (Derived_Type,
5432 Relative_Deadline_Variable (Parent_Type));
5435 if Present (Discriminant_Specifications (N)) then
5436 Push_Scope (Derived_Type);
5437 Check_Or_Process_Discriminants (N, Derived_Type);
5439 if Constraint_Present then
5441 Expand_To_Stored_Constraint
5443 Build_Discriminant_Constraints
5445 Subtype_Indication (Type_Definition (N)), True));
5450 elsif Constraint_Present then
5452 -- Build constrained subtype and derive from it
5455 Loc : constant Source_Ptr := Sloc (N);
5456 Anon : constant Entity_Id :=
5457 Make_Defining_Identifier (Loc,
5458 Chars => New_External_Name (Chars (Derived_Type), 'T'));
5463 Make_Subtype_Declaration (Loc,
5464 Defining_Identifier => Anon,
5465 Subtype_Indication =>
5466 Subtype_Indication (Type_Definition (N)));
5467 Insert_Before (N, Decl);
5470 Rewrite (Subtype_Indication (Type_Definition (N)),
5471 New_Occurrence_Of (Anon, Loc));
5472 Set_Analyzed (Derived_Type, False);
5478 -- By default, operations and private data are inherited from parent.
5479 -- However, in the presence of bound discriminants, a new corresponding
5480 -- record will be created, see below.
5482 Set_Has_Discriminants
5483 (Derived_Type, Has_Discriminants (Parent_Type));
5484 Set_Corresponding_Record_Type
5485 (Derived_Type, Corresponding_Record_Type (Parent_Type));
5487 -- Is_Constrained is set according the parent subtype, but is set to
5488 -- False if the derived type is declared with new discriminants.
5492 (Is_Constrained (Parent_Type) or else Constraint_Present)
5493 and then not Present (Discriminant_Specifications (N)));
5495 if Constraint_Present then
5496 if not Has_Discriminants (Parent_Type) then
5497 Error_Msg_N ("untagged parent must have discriminants", N);
5499 elsif Present (Discriminant_Specifications (N)) then
5501 -- Verify that new discriminants are used to constrain old ones
5506 (Constraint (Subtype_Indication (Type_Definition (N)))));
5508 Old_Disc := First_Discriminant (Parent_Type);
5510 while Present (D_Constraint) loop
5511 if Nkind (D_Constraint) /= N_Discriminant_Association then
5513 -- Positional constraint. If it is a reference to a new
5514 -- discriminant, it constrains the corresponding old one.
5516 if Nkind (D_Constraint) = N_Identifier then
5517 New_Disc := First_Discriminant (Derived_Type);
5518 while Present (New_Disc) loop
5519 exit when Chars (New_Disc) = Chars (D_Constraint);
5520 Next_Discriminant (New_Disc);
5523 if Present (New_Disc) then
5524 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
5528 Next_Discriminant (Old_Disc);
5530 -- if this is a named constraint, search by name for the old
5531 -- discriminants constrained by the new one.
5533 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
5535 -- Find new discriminant with that name
5537 New_Disc := First_Discriminant (Derived_Type);
5538 while Present (New_Disc) loop
5540 Chars (New_Disc) = Chars (Expression (D_Constraint));
5541 Next_Discriminant (New_Disc);
5544 if Present (New_Disc) then
5546 -- Verify that new discriminant renames some discriminant
5547 -- of the parent type, and associate the new discriminant
5548 -- with one or more old ones that it renames.
5554 Selector := First (Selector_Names (D_Constraint));
5555 while Present (Selector) loop
5556 Old_Disc := First_Discriminant (Parent_Type);
5557 while Present (Old_Disc) loop
5558 exit when Chars (Old_Disc) = Chars (Selector);
5559 Next_Discriminant (Old_Disc);
5562 if Present (Old_Disc) then
5563 Set_Corresponding_Discriminant
5564 (New_Disc, Old_Disc);
5573 Next (D_Constraint);
5576 New_Disc := First_Discriminant (Derived_Type);
5577 while Present (New_Disc) loop
5578 if No (Corresponding_Discriminant (New_Disc)) then
5580 ("new discriminant& must constrain old one", N, New_Disc);
5583 Subtypes_Statically_Compatible
5585 Etype (Corresponding_Discriminant (New_Disc)))
5588 ("& not statically compatible with parent discriminant",
5592 Next_Discriminant (New_Disc);
5596 elsif Present (Discriminant_Specifications (N)) then
5598 ("missing discriminant constraint in untagged derivation", N);
5601 -- The entity chain of the derived type includes the new discriminants
5602 -- but shares operations with the parent.
5604 if Present (Discriminant_Specifications (N)) then
5605 Old_Disc := First_Discriminant (Parent_Type);
5606 while Present (Old_Disc) loop
5607 if No (Next_Entity (Old_Disc))
5608 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
5611 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
5615 Next_Discriminant (Old_Disc);
5619 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
5620 if Has_Discriminants (Parent_Type) then
5621 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5622 Set_Discriminant_Constraint (
5623 Derived_Type, Discriminant_Constraint (Parent_Type));
5627 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
5629 Set_Has_Completion (Derived_Type);
5631 if Corr_Decl_Needed then
5632 Set_Stored_Constraint (Derived_Type, New_Constraint);
5633 Insert_After (N, Corr_Decl);
5634 Analyze (Corr_Decl);
5635 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
5637 end Build_Derived_Concurrent_Type;
5639 ------------------------------------
5640 -- Build_Derived_Enumeration_Type --
5641 ------------------------------------
5643 procedure Build_Derived_Enumeration_Type
5645 Parent_Type : Entity_Id;
5646 Derived_Type : Entity_Id)
5648 Loc : constant Source_Ptr := Sloc (N);
5649 Def : constant Node_Id := Type_Definition (N);
5650 Indic : constant Node_Id := Subtype_Indication (Def);
5651 Implicit_Base : Entity_Id;
5652 Literal : Entity_Id;
5653 New_Lit : Entity_Id;
5654 Literals_List : List_Id;
5655 Type_Decl : Node_Id;
5657 Rang_Expr : Node_Id;
5660 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
5661 -- not have explicit literals lists we need to process types derived
5662 -- from them specially. This is handled by Derived_Standard_Character.
5663 -- If the parent type is a generic type, there are no literals either,
5664 -- and we construct the same skeletal representation as for the generic
5667 if Is_Standard_Character_Type (Parent_Type) then
5668 Derived_Standard_Character (N, Parent_Type, Derived_Type);
5670 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
5676 if Nkind (Indic) /= N_Subtype_Indication then
5678 Make_Attribute_Reference (Loc,
5679 Attribute_Name => Name_First,
5680 Prefix => New_Reference_To (Derived_Type, Loc));
5681 Set_Etype (Lo, Derived_Type);
5684 Make_Attribute_Reference (Loc,
5685 Attribute_Name => Name_Last,
5686 Prefix => New_Reference_To (Derived_Type, Loc));
5687 Set_Etype (Hi, Derived_Type);
5689 Set_Scalar_Range (Derived_Type,
5695 -- Analyze subtype indication and verify compatibility
5696 -- with parent type.
5698 if Base_Type (Process_Subtype (Indic, N)) /=
5699 Base_Type (Parent_Type)
5702 ("illegal constraint for formal discrete type", N);
5708 -- If a constraint is present, analyze the bounds to catch
5709 -- premature usage of the derived literals.
5711 if Nkind (Indic) = N_Subtype_Indication
5712 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
5714 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
5715 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
5718 -- Introduce an implicit base type for the derived type even if there
5719 -- is no constraint attached to it, since this seems closer to the
5720 -- Ada semantics. Build a full type declaration tree for the derived
5721 -- type using the implicit base type as the defining identifier. The
5722 -- build a subtype declaration tree which applies the constraint (if
5723 -- any) have it replace the derived type declaration.
5725 Literal := First_Literal (Parent_Type);
5726 Literals_List := New_List;
5727 while Present (Literal)
5728 and then Ekind (Literal) = E_Enumeration_Literal
5730 -- Literals of the derived type have the same representation as
5731 -- those of the parent type, but this representation can be
5732 -- overridden by an explicit representation clause. Indicate
5733 -- that there is no explicit representation given yet. These
5734 -- derived literals are implicit operations of the new type,
5735 -- and can be overridden by explicit ones.
5737 if Nkind (Literal) = N_Defining_Character_Literal then
5739 Make_Defining_Character_Literal (Loc, Chars (Literal));
5741 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
5744 Set_Ekind (New_Lit, E_Enumeration_Literal);
5745 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
5746 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
5747 Set_Enumeration_Rep_Expr (New_Lit, Empty);
5748 Set_Alias (New_Lit, Literal);
5749 Set_Is_Known_Valid (New_Lit, True);
5751 Append (New_Lit, Literals_List);
5752 Next_Literal (Literal);
5756 Make_Defining_Identifier (Sloc (Derived_Type),
5757 Chars => New_External_Name (Chars (Derived_Type), 'B'));
5759 -- Indicate the proper nature of the derived type. This must be done
5760 -- before analysis of the literals, to recognize cases when a literal
5761 -- may be hidden by a previous explicit function definition (cf.
5764 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
5765 Set_Etype (Derived_Type, Implicit_Base);
5768 Make_Full_Type_Declaration (Loc,
5769 Defining_Identifier => Implicit_Base,
5770 Discriminant_Specifications => No_List,
5772 Make_Enumeration_Type_Definition (Loc, Literals_List));
5774 Mark_Rewrite_Insertion (Type_Decl);
5775 Insert_Before (N, Type_Decl);
5776 Analyze (Type_Decl);
5778 -- After the implicit base is analyzed its Etype needs to be changed
5779 -- to reflect the fact that it is derived from the parent type which
5780 -- was ignored during analysis. We also set the size at this point.
5782 Set_Etype (Implicit_Base, Parent_Type);
5784 Set_Size_Info (Implicit_Base, Parent_Type);
5785 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
5786 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
5788 -- Copy other flags from parent type
5790 Set_Has_Non_Standard_Rep
5791 (Implicit_Base, Has_Non_Standard_Rep
5793 Set_Has_Pragma_Ordered
5794 (Implicit_Base, Has_Pragma_Ordered
5796 Set_Has_Delayed_Freeze (Implicit_Base);
5798 -- Process the subtype indication including a validation check on the
5799 -- constraint, if any. If a constraint is given, its bounds must be
5800 -- implicitly converted to the new type.
5802 if Nkind (Indic) = N_Subtype_Indication then
5804 R : constant Node_Id :=
5805 Range_Expression (Constraint (Indic));
5808 if Nkind (R) = N_Range then
5809 Hi := Build_Scalar_Bound
5810 (High_Bound (R), Parent_Type, Implicit_Base);
5811 Lo := Build_Scalar_Bound
5812 (Low_Bound (R), Parent_Type, Implicit_Base);
5815 -- Constraint is a Range attribute. Replace with explicit
5816 -- mention of the bounds of the prefix, which must be a
5819 Analyze (Prefix (R));
5821 Convert_To (Implicit_Base,
5822 Make_Attribute_Reference (Loc,
5823 Attribute_Name => Name_Last,
5825 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
5828 Convert_To (Implicit_Base,
5829 Make_Attribute_Reference (Loc,
5830 Attribute_Name => Name_First,
5832 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
5839 (Type_High_Bound (Parent_Type),
5840 Parent_Type, Implicit_Base);
5843 (Type_Low_Bound (Parent_Type),
5844 Parent_Type, Implicit_Base);
5852 -- If we constructed a default range for the case where no range
5853 -- was given, then the expressions in the range must not freeze
5854 -- since they do not correspond to expressions in the source.
5856 if Nkind (Indic) /= N_Subtype_Indication then
5857 Set_Must_Not_Freeze (Lo);
5858 Set_Must_Not_Freeze (Hi);
5859 Set_Must_Not_Freeze (Rang_Expr);
5863 Make_Subtype_Declaration (Loc,
5864 Defining_Identifier => Derived_Type,
5865 Subtype_Indication =>
5866 Make_Subtype_Indication (Loc,
5867 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
5869 Make_Range_Constraint (Loc,
5870 Range_Expression => Rang_Expr))));
5874 -- If pragma Discard_Names applies on the first subtype of the parent
5875 -- type, then it must be applied on this subtype as well.
5877 if Einfo.Discard_Names (First_Subtype (Parent_Type)) then
5878 Set_Discard_Names (Derived_Type);
5881 -- Apply a range check. Since this range expression doesn't have an
5882 -- Etype, we have to specifically pass the Source_Typ parameter. Is
5885 if Nkind (Indic) = N_Subtype_Indication then
5886 Apply_Range_Check (Range_Expression (Constraint (Indic)),
5888 Source_Typ => Entity (Subtype_Mark (Indic)));
5891 end Build_Derived_Enumeration_Type;
5893 --------------------------------
5894 -- Build_Derived_Numeric_Type --
5895 --------------------------------
5897 procedure Build_Derived_Numeric_Type
5899 Parent_Type : Entity_Id;
5900 Derived_Type : Entity_Id)
5902 Loc : constant Source_Ptr := Sloc (N);
5903 Tdef : constant Node_Id := Type_Definition (N);
5904 Indic : constant Node_Id := Subtype_Indication (Tdef);
5905 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5906 No_Constraint : constant Boolean := Nkind (Indic) /=
5907 N_Subtype_Indication;
5908 Implicit_Base : Entity_Id;
5914 -- Process the subtype indication including a validation check on
5915 -- the constraint if any.
5917 Discard_Node (Process_Subtype (Indic, N));
5919 -- Introduce an implicit base type for the derived type even if there
5920 -- is no constraint attached to it, since this seems closer to the Ada
5924 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5926 Set_Etype (Implicit_Base, Parent_Base);
5927 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5928 Set_Size_Info (Implicit_Base, Parent_Base);
5929 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
5930 Set_Parent (Implicit_Base, Parent (Derived_Type));
5931 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
5933 -- Set RM Size for discrete type or decimal fixed-point type
5934 -- Ordinary fixed-point is excluded, why???
5936 if Is_Discrete_Type (Parent_Base)
5937 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
5939 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
5942 Set_Has_Delayed_Freeze (Implicit_Base);
5944 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
5945 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
5947 Set_Scalar_Range (Implicit_Base,
5952 if Has_Infinities (Parent_Base) then
5953 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
5956 -- The Derived_Type, which is the entity of the declaration, is a
5957 -- subtype of the implicit base. Its Ekind is a subtype, even in the
5958 -- absence of an explicit constraint.
5960 Set_Etype (Derived_Type, Implicit_Base);
5962 -- If we did not have a constraint, then the Ekind is set from the
5963 -- parent type (otherwise Process_Subtype has set the bounds)
5965 if No_Constraint then
5966 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
5969 -- If we did not have a range constraint, then set the range from the
5970 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
5973 or else not Has_Range_Constraint (Indic)
5975 Set_Scalar_Range (Derived_Type,
5977 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
5978 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
5979 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5981 if Has_Infinities (Parent_Type) then
5982 Set_Includes_Infinities (Scalar_Range (Derived_Type));
5985 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
5988 Set_Is_Descendent_Of_Address (Derived_Type,
5989 Is_Descendent_Of_Address (Parent_Type));
5990 Set_Is_Descendent_Of_Address (Implicit_Base,
5991 Is_Descendent_Of_Address (Parent_Type));
5993 -- Set remaining type-specific fields, depending on numeric type
5995 if Is_Modular_Integer_Type (Parent_Type) then
5996 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
5998 Set_Non_Binary_Modulus
5999 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
6002 (Implicit_Base, Is_Known_Valid (Parent_Base));
6004 elsif Is_Floating_Point_Type (Parent_Type) then
6006 -- Digits of base type is always copied from the digits value of
6007 -- the parent base type, but the digits of the derived type will
6008 -- already have been set if there was a constraint present.
6010 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6011 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
6013 if No_Constraint then
6014 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
6017 elsif Is_Fixed_Point_Type (Parent_Type) then
6019 -- Small of base type and derived type are always copied from the
6020 -- parent base type, since smalls never change. The delta of the
6021 -- base type is also copied from the parent base type. However the
6022 -- delta of the derived type will have been set already if a
6023 -- constraint was present.
6025 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
6026 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
6027 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
6029 if No_Constraint then
6030 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
6033 -- The scale and machine radix in the decimal case are always
6034 -- copied from the parent base type.
6036 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
6037 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
6038 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
6040 Set_Machine_Radix_10
6041 (Derived_Type, Machine_Radix_10 (Parent_Base));
6042 Set_Machine_Radix_10
6043 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6045 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6047 if No_Constraint then
6048 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6051 -- the analysis of the subtype_indication sets the
6052 -- digits value of the derived type.
6059 -- The type of the bounds is that of the parent type, and they
6060 -- must be converted to the derived type.
6062 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
6064 -- The implicit_base should be frozen when the derived type is frozen,
6065 -- but note that it is used in the conversions of the bounds. For fixed
6066 -- types we delay the determination of the bounds until the proper
6067 -- freezing point. For other numeric types this is rejected by GCC, for
6068 -- reasons that are currently unclear (???), so we choose to freeze the
6069 -- implicit base now. In the case of integers and floating point types
6070 -- this is harmless because subsequent representation clauses cannot
6071 -- affect anything, but it is still baffling that we cannot use the
6072 -- same mechanism for all derived numeric types.
6074 -- There is a further complication: actually *some* representation
6075 -- clauses can affect the implicit base type. Namely, attribute
6076 -- definition clauses for stream-oriented attributes need to set the
6077 -- corresponding TSS entries on the base type, and this normally cannot
6078 -- be done after the base type is frozen, so the circuitry in
6079 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility and
6080 -- not use Set_TSS in this case.
6082 if Is_Fixed_Point_Type (Parent_Type) then
6083 Conditional_Delay (Implicit_Base, Parent_Type);
6085 Freeze_Before (N, Implicit_Base);
6087 end Build_Derived_Numeric_Type;
6089 --------------------------------
6090 -- Build_Derived_Private_Type --
6091 --------------------------------
6093 procedure Build_Derived_Private_Type
6095 Parent_Type : Entity_Id;
6096 Derived_Type : Entity_Id;
6097 Is_Completion : Boolean;
6098 Derive_Subps : Boolean := True)
6100 Loc : constant Source_Ptr := Sloc (N);
6101 Der_Base : Entity_Id;
6103 Full_Decl : Node_Id := Empty;
6104 Full_Der : Entity_Id;
6106 Last_Discr : Entity_Id;
6107 Par_Scope : constant Entity_Id := Scope (Base_Type (Parent_Type));
6108 Swapped : Boolean := False;
6110 procedure Copy_And_Build;
6111 -- Copy derived type declaration, replace parent with its full view,
6112 -- and analyze new declaration.
6114 --------------------
6115 -- Copy_And_Build --
6116 --------------------
6118 procedure Copy_And_Build is
6122 if Ekind (Parent_Type) in Record_Kind
6124 (Ekind (Parent_Type) in Enumeration_Kind
6125 and then not Is_Standard_Character_Type (Parent_Type)
6126 and then not Is_Generic_Type (Root_Type (Parent_Type)))
6128 Full_N := New_Copy_Tree (N);
6129 Insert_After (N, Full_N);
6130 Build_Derived_Type (
6131 Full_N, Parent_Type, Full_Der, True, Derive_Subps => False);
6134 Build_Derived_Type (
6135 N, Parent_Type, Full_Der, True, Derive_Subps => False);
6139 -- Start of processing for Build_Derived_Private_Type
6142 if Is_Tagged_Type (Parent_Type) then
6143 Full_P := Full_View (Parent_Type);
6145 -- A type extension of a type with unknown discriminants is an
6146 -- indefinite type that the back-end cannot handle directly.
6147 -- We treat it as a private type, and build a completion that is
6148 -- derived from the full view of the parent, and hopefully has
6149 -- known discriminants.
6151 -- If the full view of the parent type has an underlying record view,
6152 -- use it to generate the underlying record view of this derived type
6153 -- (required for chains of derivations with unknown discriminants).
6155 -- Minor optimization: we avoid the generation of useless underlying
6156 -- record view entities if the private type declaration has unknown
6157 -- discriminants but its corresponding full view has no
6160 if Has_Unknown_Discriminants (Parent_Type)
6161 and then Present (Full_P)
6162 and then (Has_Discriminants (Full_P)
6163 or else Present (Underlying_Record_View (Full_P)))
6164 and then not In_Open_Scopes (Par_Scope)
6165 and then Expander_Active
6168 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
6169 New_Ext : constant Node_Id :=
6171 (Record_Extension_Part (Type_Definition (N)));
6175 Build_Derived_Record_Type
6176 (N, Parent_Type, Derived_Type, Derive_Subps);
6178 -- Build anonymous completion, as a derivation from the full
6179 -- view of the parent. This is not a completion in the usual
6180 -- sense, because the current type is not private.
6183 Make_Full_Type_Declaration (Loc,
6184 Defining_Identifier => Full_Der,
6186 Make_Derived_Type_Definition (Loc,
6187 Subtype_Indication =>
6189 (Subtype_Indication (Type_Definition (N))),
6190 Record_Extension_Part => New_Ext));
6192 -- If the parent type has an underlying record view, use it
6193 -- here to build the new underlying record view.
6195 if Present (Underlying_Record_View (Full_P)) then
6197 (Nkind (Subtype_Indication (Type_Definition (Decl)))
6199 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
6200 Underlying_Record_View (Full_P));
6203 Install_Private_Declarations (Par_Scope);
6204 Install_Visible_Declarations (Par_Scope);
6205 Insert_Before (N, Decl);
6207 -- Mark entity as an underlying record view before analysis,
6208 -- to avoid generating the list of its primitive operations
6209 -- (which is not really required for this entity) and thus
6210 -- prevent spurious errors associated with missing overriding
6211 -- of abstract primitives (overridden only for Derived_Type).
6213 Set_Ekind (Full_Der, E_Record_Type);
6214 Set_Is_Underlying_Record_View (Full_Der);
6218 pragma Assert (Has_Discriminants (Full_Der)
6219 and then not Has_Unknown_Discriminants (Full_Der));
6221 Uninstall_Declarations (Par_Scope);
6223 -- Freeze the underlying record view, to prevent generation of
6224 -- useless dispatching information, which is simply shared with
6225 -- the real derived type.
6227 Set_Is_Frozen (Full_Der);
6229 -- Set up links between real entity and underlying record view
6231 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
6232 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
6235 -- If discriminants are known, build derived record
6238 Build_Derived_Record_Type
6239 (N, Parent_Type, Derived_Type, Derive_Subps);
6244 elsif Has_Discriminants (Parent_Type) then
6245 if Present (Full_View (Parent_Type)) then
6246 if not Is_Completion then
6248 -- Copy declaration for subsequent analysis, to provide a
6249 -- completion for what is a private declaration. Indicate that
6250 -- the full type is internally generated.
6252 Full_Decl := New_Copy_Tree (N);
6253 Full_Der := New_Copy (Derived_Type);
6254 Set_Comes_From_Source (Full_Decl, False);
6255 Set_Comes_From_Source (Full_Der, False);
6256 Set_Parent (Full_Der, Full_Decl);
6258 Insert_After (N, Full_Decl);
6261 -- If this is a completion, the full view being built is itself
6262 -- private. We build a subtype of the parent with the same
6263 -- constraints as this full view, to convey to the back end the
6264 -- constrained components and the size of this subtype. If the
6265 -- parent is constrained, its full view can serve as the
6266 -- underlying full view of the derived type.
6268 if No (Discriminant_Specifications (N)) then
6269 if Nkind (Subtype_Indication (Type_Definition (N))) =
6270 N_Subtype_Indication
6272 Build_Underlying_Full_View (N, Derived_Type, Parent_Type);
6274 elsif Is_Constrained (Full_View (Parent_Type)) then
6275 Set_Underlying_Full_View
6276 (Derived_Type, Full_View (Parent_Type));
6280 -- If there are new discriminants, the parent subtype is
6281 -- constrained by them, but it is not clear how to build
6282 -- the Underlying_Full_View in this case???
6289 -- Build partial view of derived type from partial view of parent
6291 Build_Derived_Record_Type
6292 (N, Parent_Type, Derived_Type, Derive_Subps);
6294 if Present (Full_View (Parent_Type)) and then not Is_Completion then
6295 if not In_Open_Scopes (Par_Scope)
6296 or else not In_Same_Source_Unit (N, Parent_Type)
6298 -- Swap partial and full views temporarily
6300 Install_Private_Declarations (Par_Scope);
6301 Install_Visible_Declarations (Par_Scope);
6305 -- Build full view of derived type from full view of parent which
6306 -- is now installed. Subprograms have been derived on the partial
6307 -- view, the completion does not derive them anew.
6309 if not Is_Tagged_Type (Parent_Type) then
6311 -- If the parent is itself derived from another private type,
6312 -- installing the private declarations has not affected its
6313 -- privacy status, so use its own full view explicitly.
6315 if Is_Private_Type (Parent_Type) then
6316 Build_Derived_Record_Type
6317 (Full_Decl, Full_View (Parent_Type), Full_Der, False);
6319 Build_Derived_Record_Type
6320 (Full_Decl, Parent_Type, Full_Der, False);
6324 -- If full view of parent is tagged, the completion inherits
6325 -- the proper primitive operations.
6327 Set_Defining_Identifier (Full_Decl, Full_Der);
6328 Build_Derived_Record_Type
6329 (Full_Decl, Parent_Type, Full_Der, Derive_Subps);
6332 -- The full declaration has been introduced into the tree and
6333 -- processed in the step above. It should not be analyzed again
6334 -- (when encountered later in the current list of declarations)
6335 -- to prevent spurious name conflicts. The full entity remains
6338 Set_Analyzed (Full_Decl);
6341 Uninstall_Declarations (Par_Scope);
6343 if In_Open_Scopes (Par_Scope) then
6344 Install_Visible_Declarations (Par_Scope);
6348 Der_Base := Base_Type (Derived_Type);
6349 Set_Full_View (Derived_Type, Full_Der);
6350 Set_Full_View (Der_Base, Base_Type (Full_Der));
6352 -- Copy the discriminant list from full view to the partial views
6353 -- (base type and its subtype). Gigi requires that the partial and
6354 -- full views have the same discriminants.
6356 -- Note that since the partial view is pointing to discriminants
6357 -- in the full view, their scope will be that of the full view.
6358 -- This might cause some front end problems and need adjustment???
6360 Discr := First_Discriminant (Base_Type (Full_Der));
6361 Set_First_Entity (Der_Base, Discr);
6364 Last_Discr := Discr;
6365 Next_Discriminant (Discr);
6366 exit when No (Discr);
6369 Set_Last_Entity (Der_Base, Last_Discr);
6371 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
6372 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
6373 Set_Stored_Constraint (Full_Der, Stored_Constraint (Derived_Type));
6376 -- If this is a completion, the derived type stays private and
6377 -- there is no need to create a further full view, except in the
6378 -- unusual case when the derivation is nested within a child unit,
6384 elsif Present (Full_View (Parent_Type))
6385 and then Has_Discriminants (Full_View (Parent_Type))
6387 if Has_Unknown_Discriminants (Parent_Type)
6388 and then Nkind (Subtype_Indication (Type_Definition (N))) =
6389 N_Subtype_Indication
6392 ("cannot constrain type with unknown discriminants",
6393 Subtype_Indication (Type_Definition (N)));
6397 -- If full view of parent is a record type, build full view as a
6398 -- derivation from the parent's full view. Partial view remains
6399 -- private. For code generation and linking, the full view must have
6400 -- the same public status as the partial one. This full view is only
6401 -- needed if the parent type is in an enclosing scope, so that the
6402 -- full view may actually become visible, e.g. in a child unit. This
6403 -- is both more efficient, and avoids order of freezing problems with
6404 -- the added entities.
6406 if not Is_Private_Type (Full_View (Parent_Type))
6407 and then (In_Open_Scopes (Scope (Parent_Type)))
6410 Make_Defining_Identifier
6411 (Sloc (Derived_Type), Chars (Derived_Type));
6412 Set_Is_Itype (Full_Der);
6413 Set_Has_Private_Declaration (Full_Der);
6414 Set_Has_Private_Declaration (Derived_Type);
6415 Set_Associated_Node_For_Itype (Full_Der, N);
6416 Set_Parent (Full_Der, Parent (Derived_Type));
6417 Set_Full_View (Derived_Type, Full_Der);
6418 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
6419 Full_P := Full_View (Parent_Type);
6420 Exchange_Declarations (Parent_Type);
6422 Exchange_Declarations (Full_P);
6425 Build_Derived_Record_Type
6426 (N, Full_View (Parent_Type), Derived_Type,
6427 Derive_Subps => False);
6430 -- In any case, the primitive operations are inherited from the
6431 -- parent type, not from the internal full view.
6433 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
6435 if Derive_Subps then
6436 Derive_Subprograms (Parent_Type, Derived_Type);
6440 -- Untagged type, No discriminants on either view
6442 if Nkind (Subtype_Indication (Type_Definition (N))) =
6443 N_Subtype_Indication
6446 ("illegal constraint on type without discriminants", N);
6449 if Present (Discriminant_Specifications (N))
6450 and then Present (Full_View (Parent_Type))
6451 and then not Is_Tagged_Type (Full_View (Parent_Type))
6453 Error_Msg_N ("cannot add discriminants to untagged type", N);
6456 Set_Stored_Constraint (Derived_Type, No_Elist);
6457 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6458 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
6459 Set_Has_Controlled_Component
6460 (Derived_Type, Has_Controlled_Component
6463 -- Direct controlled types do not inherit Finalize_Storage_Only flag
6465 if not Is_Controlled (Parent_Type) then
6466 Set_Finalize_Storage_Only
6467 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
6470 -- Construct the implicit full view by deriving from full view of the
6471 -- parent type. In order to get proper visibility, we install the
6472 -- parent scope and its declarations.
6474 -- ??? If the parent is untagged private and its completion is
6475 -- tagged, this mechanism will not work because we cannot derive from
6476 -- the tagged full view unless we have an extension.
6478 if Present (Full_View (Parent_Type))
6479 and then not Is_Tagged_Type (Full_View (Parent_Type))
6480 and then not Is_Completion
6483 Make_Defining_Identifier
6484 (Sloc (Derived_Type), Chars (Derived_Type));
6485 Set_Is_Itype (Full_Der);
6486 Set_Has_Private_Declaration (Full_Der);
6487 Set_Has_Private_Declaration (Derived_Type);
6488 Set_Associated_Node_For_Itype (Full_Der, N);
6489 Set_Parent (Full_Der, Parent (Derived_Type));
6490 Set_Full_View (Derived_Type, Full_Der);
6492 if not In_Open_Scopes (Par_Scope) then
6493 Install_Private_Declarations (Par_Scope);
6494 Install_Visible_Declarations (Par_Scope);
6496 Uninstall_Declarations (Par_Scope);
6498 -- If parent scope is open and in another unit, and parent has a
6499 -- completion, then the derivation is taking place in the visible
6500 -- part of a child unit. In that case retrieve the full view of
6501 -- the parent momentarily.
6503 elsif not In_Same_Source_Unit (N, Parent_Type) then
6504 Full_P := Full_View (Parent_Type);
6505 Exchange_Declarations (Parent_Type);
6507 Exchange_Declarations (Full_P);
6509 -- Otherwise it is a local derivation
6515 Set_Scope (Full_Der, Current_Scope);
6516 Set_Is_First_Subtype (Full_Der,
6517 Is_First_Subtype (Derived_Type));
6518 Set_Has_Size_Clause (Full_Der, False);
6519 Set_Has_Alignment_Clause (Full_Der, False);
6520 Set_Next_Entity (Full_Der, Empty);
6521 Set_Has_Delayed_Freeze (Full_Der);
6522 Set_Is_Frozen (Full_Der, False);
6523 Set_Freeze_Node (Full_Der, Empty);
6524 Set_Depends_On_Private (Full_Der,
6525 Has_Private_Component (Full_Der));
6526 Set_Public_Status (Full_Der);
6530 Set_Has_Unknown_Discriminants (Derived_Type,
6531 Has_Unknown_Discriminants (Parent_Type));
6533 if Is_Private_Type (Derived_Type) then
6534 Set_Private_Dependents (Derived_Type, New_Elmt_List);
6537 if Is_Private_Type (Parent_Type)
6538 and then Base_Type (Parent_Type) = Parent_Type
6539 and then In_Open_Scopes (Scope (Parent_Type))
6541 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
6543 if Is_Child_Unit (Scope (Current_Scope))
6544 and then Is_Completion
6545 and then In_Private_Part (Current_Scope)
6546 and then Scope (Parent_Type) /= Current_Scope
6548 -- This is the unusual case where a type completed by a private
6549 -- derivation occurs within a package nested in a child unit, and
6550 -- the parent is declared in an ancestor. In this case, the full
6551 -- view of the parent type will become visible in the body of
6552 -- the enclosing child, and only then will the current type be
6553 -- possibly non-private. We build a underlying full view that
6554 -- will be installed when the enclosing child body is compiled.
6557 Make_Defining_Identifier
6558 (Sloc (Derived_Type), Chars (Derived_Type));
6559 Set_Is_Itype (Full_Der);
6560 Build_Itype_Reference (Full_Der, N);
6562 -- The full view will be used to swap entities on entry/exit to
6563 -- the body, and must appear in the entity list for the package.
6565 Append_Entity (Full_Der, Scope (Derived_Type));
6566 Set_Has_Private_Declaration (Full_Der);
6567 Set_Has_Private_Declaration (Derived_Type);
6568 Set_Associated_Node_For_Itype (Full_Der, N);
6569 Set_Parent (Full_Der, Parent (Derived_Type));
6570 Full_P := Full_View (Parent_Type);
6571 Exchange_Declarations (Parent_Type);
6573 Exchange_Declarations (Full_P);
6574 Set_Underlying_Full_View (Derived_Type, Full_Der);
6577 end Build_Derived_Private_Type;
6579 -------------------------------
6580 -- Build_Derived_Record_Type --
6581 -------------------------------
6585 -- Ideally we would like to use the same model of type derivation for
6586 -- tagged and untagged record types. Unfortunately this is not quite
6587 -- possible because the semantics of representation clauses is different
6588 -- for tagged and untagged records under inheritance. Consider the
6591 -- type R (...) is [tagged] record ... end record;
6592 -- type T (...) is new R (...) [with ...];
6594 -- The representation clauses for T can specify a completely different
6595 -- record layout from R's. Hence the same component can be placed in two
6596 -- very different positions in objects of type T and R. If R and T are
6597 -- tagged types, representation clauses for T can only specify the layout
6598 -- of non inherited components, thus components that are common in R and T
6599 -- have the same position in objects of type R and T.
6601 -- This has two implications. The first is that the entire tree for R's
6602 -- declaration needs to be copied for T in the untagged case, so that T
6603 -- can be viewed as a record type of its own with its own representation
6604 -- clauses. The second implication is the way we handle discriminants.
6605 -- Specifically, in the untagged case we need a way to communicate to Gigi
6606 -- what are the real discriminants in the record, while for the semantics
6607 -- we need to consider those introduced by the user to rename the
6608 -- discriminants in the parent type. This is handled by introducing the
6609 -- notion of stored discriminants. See below for more.
6611 -- Fortunately the way regular components are inherited can be handled in
6612 -- the same way in tagged and untagged types.
6614 -- To complicate things a bit more the private view of a private extension
6615 -- cannot be handled in the same way as the full view (for one thing the
6616 -- semantic rules are somewhat different). We will explain what differs
6619 -- 2. DISCRIMINANTS UNDER INHERITANCE
6621 -- The semantic rules governing the discriminants of derived types are
6624 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
6625 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
6627 -- If parent type has discriminants, then the discriminants that are
6628 -- declared in the derived type are [3.4 (11)]:
6630 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
6633 -- o Otherwise, each discriminant of the parent type (implicitly declared
6634 -- in the same order with the same specifications). In this case, the
6635 -- discriminants are said to be "inherited", or if unknown in the parent
6636 -- are also unknown in the derived type.
6638 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
6640 -- o The parent subtype shall be constrained;
6642 -- o If the parent type is not a tagged type, then each discriminant of
6643 -- the derived type shall be used in the constraint defining a parent
6644 -- subtype. [Implementation note: This ensures that the new discriminant
6645 -- can share storage with an existing discriminant.]
6647 -- For the derived type each discriminant of the parent type is either
6648 -- inherited, constrained to equal some new discriminant of the derived
6649 -- type, or constrained to the value of an expression.
6651 -- When inherited or constrained to equal some new discriminant, the
6652 -- parent discriminant and the discriminant of the derived type are said
6655 -- If a discriminant of the parent type is constrained to a specific value
6656 -- in the derived type definition, then the discriminant is said to be
6657 -- "specified" by that derived type definition.
6659 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
6661 -- We have spoken about stored discriminants in point 1 (introduction)
6662 -- above. There are two sort of stored discriminants: implicit and
6663 -- explicit. As long as the derived type inherits the same discriminants as
6664 -- the root record type, stored discriminants are the same as regular
6665 -- discriminants, and are said to be implicit. However, if any discriminant
6666 -- in the root type was renamed in the derived type, then the derived
6667 -- type will contain explicit stored discriminants. Explicit stored
6668 -- discriminants are discriminants in addition to the semantically visible
6669 -- discriminants defined for the derived type. Stored discriminants are
6670 -- used by Gigi to figure out what are the physical discriminants in
6671 -- objects of the derived type (see precise definition in einfo.ads).
6672 -- As an example, consider the following:
6674 -- type R (D1, D2, D3 : Int) is record ... end record;
6675 -- type T1 is new R;
6676 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
6677 -- type T3 is new T2;
6678 -- type T4 (Y : Int) is new T3 (Y, 99);
6680 -- The following table summarizes the discriminants and stored
6681 -- discriminants in R and T1 through T4.
6683 -- Type Discrim Stored Discrim Comment
6684 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
6685 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
6686 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
6687 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
6688 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
6690 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
6691 -- find the corresponding discriminant in the parent type, while
6692 -- Original_Record_Component (abbreviated ORC below), the actual physical
6693 -- component that is renamed. Finally the field Is_Completely_Hidden
6694 -- (abbreviated ICH below) is set for all explicit stored discriminants
6695 -- (see einfo.ads for more info). For the above example this gives:
6697 -- Discrim CD ORC ICH
6698 -- ^^^^^^^ ^^ ^^^ ^^^
6699 -- D1 in R empty itself no
6700 -- D2 in R empty itself no
6701 -- D3 in R empty itself no
6703 -- D1 in T1 D1 in R itself no
6704 -- D2 in T1 D2 in R itself no
6705 -- D3 in T1 D3 in R itself no
6707 -- X1 in T2 D3 in T1 D3 in T2 no
6708 -- X2 in T2 D1 in T1 D1 in T2 no
6709 -- D1 in T2 empty itself yes
6710 -- D2 in T2 empty itself yes
6711 -- D3 in T2 empty itself yes
6713 -- X1 in T3 X1 in T2 D3 in T3 no
6714 -- X2 in T3 X2 in T2 D1 in T3 no
6715 -- D1 in T3 empty itself yes
6716 -- D2 in T3 empty itself yes
6717 -- D3 in T3 empty itself yes
6719 -- Y in T4 X1 in T3 D3 in T3 no
6720 -- D1 in T3 empty itself yes
6721 -- D2 in T3 empty itself yes
6722 -- D3 in T3 empty itself yes
6724 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
6726 -- Type derivation for tagged types is fairly straightforward. If no
6727 -- discriminants are specified by the derived type, these are inherited
6728 -- from the parent. No explicit stored discriminants are ever necessary.
6729 -- The only manipulation that is done to the tree is that of adding a
6730 -- _parent field with parent type and constrained to the same constraint
6731 -- specified for the parent in the derived type definition. For instance:
6733 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
6734 -- type T1 is new R with null record;
6735 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
6737 -- are changed into:
6739 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
6740 -- _parent : R (D1, D2, D3);
6743 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
6744 -- _parent : T1 (X2, 88, X1);
6747 -- The discriminants actually present in R, T1 and T2 as well as their CD,
6748 -- ORC and ICH fields are:
6750 -- Discrim CD ORC ICH
6751 -- ^^^^^^^ ^^ ^^^ ^^^
6752 -- D1 in R empty itself no
6753 -- D2 in R empty itself no
6754 -- D3 in R empty itself no
6756 -- D1 in T1 D1 in R D1 in R no
6757 -- D2 in T1 D2 in R D2 in R no
6758 -- D3 in T1 D3 in R D3 in R no
6760 -- X1 in T2 D3 in T1 D3 in R no
6761 -- X2 in T2 D1 in T1 D1 in R no
6763 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
6765 -- Regardless of whether we dealing with a tagged or untagged type
6766 -- we will transform all derived type declarations of the form
6768 -- type T is new R (...) [with ...];
6770 -- subtype S is R (...);
6771 -- type T is new S [with ...];
6773 -- type BT is new R [with ...];
6774 -- subtype T is BT (...);
6776 -- That is, the base derived type is constrained only if it has no
6777 -- discriminants. The reason for doing this is that GNAT's semantic model
6778 -- assumes that a base type with discriminants is unconstrained.
6780 -- Note that, strictly speaking, the above transformation is not always
6781 -- correct. Consider for instance the following excerpt from ACVC b34011a:
6783 -- procedure B34011A is
6784 -- type REC (D : integer := 0) is record
6789 -- type T6 is new Rec;
6790 -- function F return T6;
6795 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
6798 -- The definition of Q6.U is illegal. However transforming Q6.U into
6800 -- type BaseU is new T6;
6801 -- subtype U is BaseU (Q6.F.I)
6803 -- turns U into a legal subtype, which is incorrect. To avoid this problem
6804 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
6805 -- the transformation described above.
6807 -- There is another instance where the above transformation is incorrect.
6811 -- type Base (D : Integer) is tagged null record;
6812 -- procedure P (X : Base);
6814 -- type Der is new Base (2) with null record;
6815 -- procedure P (X : Der);
6818 -- Then the above transformation turns this into
6820 -- type Der_Base is new Base with null record;
6821 -- -- procedure P (X : Base) is implicitly inherited here
6822 -- -- as procedure P (X : Der_Base).
6824 -- subtype Der is Der_Base (2);
6825 -- procedure P (X : Der);
6826 -- -- The overriding of P (X : Der_Base) is illegal since we
6827 -- -- have a parameter conformance problem.
6829 -- To get around this problem, after having semantically processed Der_Base
6830 -- and the rewritten subtype declaration for Der, we copy Der_Base field
6831 -- Discriminant_Constraint from Der so that when parameter conformance is
6832 -- checked when P is overridden, no semantic errors are flagged.
6834 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
6836 -- Regardless of whether we are dealing with a tagged or untagged type
6837 -- we will transform all derived type declarations of the form
6839 -- type R (D1, .., Dn : ...) is [tagged] record ...;
6840 -- type T is new R [with ...];
6842 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
6844 -- The reason for such transformation is that it allows us to implement a
6845 -- very clean form of component inheritance as explained below.
6847 -- Note that this transformation is not achieved by direct tree rewriting
6848 -- and manipulation, but rather by redoing the semantic actions that the
6849 -- above transformation will entail. This is done directly in routine
6850 -- Inherit_Components.
6852 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
6854 -- In both tagged and untagged derived types, regular non discriminant
6855 -- components are inherited in the derived type from the parent type. In
6856 -- the absence of discriminants component, inheritance is straightforward
6857 -- as components can simply be copied from the parent.
6859 -- If the parent has discriminants, inheriting components constrained with
6860 -- these discriminants requires caution. Consider the following example:
6862 -- type R (D1, D2 : Positive) is [tagged] record
6863 -- S : String (D1 .. D2);
6866 -- type T1 is new R [with null record];
6867 -- type T2 (X : positive) is new R (1, X) [with null record];
6869 -- As explained in 6. above, T1 is rewritten as
6870 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
6871 -- which makes the treatment for T1 and T2 identical.
6873 -- What we want when inheriting S, is that references to D1 and D2 in R are
6874 -- replaced with references to their correct constraints, i.e. D1 and D2 in
6875 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
6876 -- with either discriminant references in the derived type or expressions.
6877 -- This replacement is achieved as follows: before inheriting R's
6878 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
6879 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
6880 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
6881 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
6882 -- by String (1 .. X).
6884 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
6886 -- We explain here the rules governing private type extensions relevant to
6887 -- type derivation. These rules are explained on the following example:
6889 -- type D [(...)] is new A [(...)] with private; <-- partial view
6890 -- type D [(...)] is new P [(...)] with null record; <-- full view
6892 -- Type A is called the ancestor subtype of the private extension.
6893 -- Type P is the parent type of the full view of the private extension. It
6894 -- must be A or a type derived from A.
6896 -- The rules concerning the discriminants of private type extensions are
6899 -- o If a private extension inherits known discriminants from the ancestor
6900 -- subtype, then the full view shall also inherit its discriminants from
6901 -- the ancestor subtype and the parent subtype of the full view shall be
6902 -- constrained if and only if the ancestor subtype is constrained.
6904 -- o If a partial view has unknown discriminants, then the full view may
6905 -- define a definite or an indefinite subtype, with or without
6908 -- o If a partial view has neither known nor unknown discriminants, then
6909 -- the full view shall define a definite subtype.
6911 -- o If the ancestor subtype of a private extension has constrained
6912 -- discriminants, then the parent subtype of the full view shall impose a
6913 -- statically matching constraint on those discriminants.
6915 -- This means that only the following forms of private extensions are
6918 -- type D is new A with private; <-- partial view
6919 -- type D is new P with null record; <-- full view
6921 -- If A has no discriminants than P has no discriminants, otherwise P must
6922 -- inherit A's discriminants.
6924 -- type D is new A (...) with private; <-- partial view
6925 -- type D is new P (:::) with null record; <-- full view
6927 -- P must inherit A's discriminants and (...) and (:::) must statically
6930 -- subtype A is R (...);
6931 -- type D is new A with private; <-- partial view
6932 -- type D is new P with null record; <-- full view
6934 -- P must have inherited R's discriminants and must be derived from A or
6935 -- any of its subtypes.
6937 -- type D (..) is new A with private; <-- partial view
6938 -- type D (..) is new P [(:::)] with null record; <-- full view
6940 -- No specific constraints on P's discriminants or constraint (:::).
6941 -- Note that A can be unconstrained, but the parent subtype P must either
6942 -- be constrained or (:::) must be present.
6944 -- type D (..) is new A [(...)] with private; <-- partial view
6945 -- type D (..) is new P [(:::)] with null record; <-- full view
6947 -- P's constraints on A's discriminants must statically match those
6948 -- imposed by (...).
6950 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
6952 -- The full view of a private extension is handled exactly as described
6953 -- above. The model chose for the private view of a private extension is
6954 -- the same for what concerns discriminants (i.e. they receive the same
6955 -- treatment as in the tagged case). However, the private view of the
6956 -- private extension always inherits the components of the parent base,
6957 -- without replacing any discriminant reference. Strictly speaking this is
6958 -- incorrect. However, Gigi never uses this view to generate code so this
6959 -- is a purely semantic issue. In theory, a set of transformations similar
6960 -- to those given in 5. and 6. above could be applied to private views of
6961 -- private extensions to have the same model of component inheritance as
6962 -- for non private extensions. However, this is not done because it would
6963 -- further complicate private type processing. Semantically speaking, this
6964 -- leaves us in an uncomfortable situation. As an example consider:
6967 -- type R (D : integer) is tagged record
6968 -- S : String (1 .. D);
6970 -- procedure P (X : R);
6971 -- type T is new R (1) with private;
6973 -- type T is new R (1) with null record;
6976 -- This is transformed into:
6979 -- type R (D : integer) is tagged record
6980 -- S : String (1 .. D);
6982 -- procedure P (X : R);
6983 -- type T is new R (1) with private;
6985 -- type BaseT is new R with null record;
6986 -- subtype T is BaseT (1);
6989 -- (strictly speaking the above is incorrect Ada)
6991 -- From the semantic standpoint the private view of private extension T
6992 -- should be flagged as constrained since one can clearly have
6996 -- in a unit withing Pack. However, when deriving subprograms for the
6997 -- private view of private extension T, T must be seen as unconstrained
6998 -- since T has discriminants (this is a constraint of the current
6999 -- subprogram derivation model). Thus, when processing the private view of
7000 -- a private extension such as T, we first mark T as unconstrained, we
7001 -- process it, we perform program derivation and just before returning from
7002 -- Build_Derived_Record_Type we mark T as constrained.
7004 -- ??? Are there are other uncomfortable cases that we will have to
7007 -- 10. RECORD_TYPE_WITH_PRIVATE complications
7009 -- Types that are derived from a visible record type and have a private
7010 -- extension present other peculiarities. They behave mostly like private
7011 -- types, but if they have primitive operations defined, these will not
7012 -- have the proper signatures for further inheritance, because other
7013 -- primitive operations will use the implicit base that we define for
7014 -- private derivations below. This affect subprogram inheritance (see
7015 -- Derive_Subprograms for details). We also derive the implicit base from
7016 -- the base type of the full view, so that the implicit base is a record
7017 -- type and not another private type, This avoids infinite loops.
7019 procedure Build_Derived_Record_Type
7021 Parent_Type : Entity_Id;
7022 Derived_Type : Entity_Id;
7023 Derive_Subps : Boolean := True)
7025 Discriminant_Specs : constant Boolean :=
7026 Present (Discriminant_Specifications (N));
7027 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
7028 Loc : constant Source_Ptr := Sloc (N);
7029 Private_Extension : constant Boolean :=
7030 Nkind (N) = N_Private_Extension_Declaration;
7031 Assoc_List : Elist_Id;
7032 Constraint_Present : Boolean;
7034 Discrim : Entity_Id;
7036 Inherit_Discrims : Boolean := False;
7037 Last_Discrim : Entity_Id;
7038 New_Base : Entity_Id;
7040 New_Discrs : Elist_Id;
7041 New_Indic : Node_Id;
7042 Parent_Base : Entity_Id;
7043 Save_Etype : Entity_Id;
7044 Save_Discr_Constr : Elist_Id;
7045 Save_Next_Entity : Entity_Id;
7048 Discs : Elist_Id := New_Elmt_List;
7049 -- An empty Discs list means that there were no constraints in the
7050 -- subtype indication or that there was an error processing it.
7053 if Ekind (Parent_Type) = E_Record_Type_With_Private
7054 and then Present (Full_View (Parent_Type))
7055 and then Has_Discriminants (Parent_Type)
7057 Parent_Base := Base_Type (Full_View (Parent_Type));
7059 Parent_Base := Base_Type (Parent_Type);
7062 -- AI05-0115 : if this is a derivation from a private type in some
7063 -- other scope that may lead to invisible components for the derived
7064 -- type, mark it accordingly.
7066 if Is_Private_Type (Parent_Type) then
7067 if Scope (Parent_Type) = Scope (Derived_Type) then
7070 elsif In_Open_Scopes (Scope (Parent_Type))
7071 and then In_Private_Part (Scope (Parent_Type))
7076 Set_Has_Private_Ancestor (Derived_Type);
7080 Set_Has_Private_Ancestor
7081 (Derived_Type, Has_Private_Ancestor (Parent_Type));
7084 -- Before we start the previously documented transformations, here is
7085 -- little fix for size and alignment of tagged types. Normally when we
7086 -- derive type D from type P, we copy the size and alignment of P as the
7087 -- default for D, and in the absence of explicit representation clauses
7088 -- for D, the size and alignment are indeed the same as the parent.
7090 -- But this is wrong for tagged types, since fields may be added, and
7091 -- the default size may need to be larger, and the default alignment may
7092 -- need to be larger.
7094 -- We therefore reset the size and alignment fields in the tagged case.
7095 -- Note that the size and alignment will in any case be at least as
7096 -- large as the parent type (since the derived type has a copy of the
7097 -- parent type in the _parent field)
7099 -- The type is also marked as being tagged here, which is needed when
7100 -- processing components with a self-referential anonymous access type
7101 -- in the call to Check_Anonymous_Access_Components below. Note that
7102 -- this flag is also set later on for completeness.
7105 Set_Is_Tagged_Type (Derived_Type);
7106 Init_Size_Align (Derived_Type);
7109 -- STEP 0a: figure out what kind of derived type declaration we have
7111 if Private_Extension then
7113 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
7116 Type_Def := Type_Definition (N);
7118 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7119 -- Parent_Base can be a private type or private extension. However,
7120 -- for tagged types with an extension the newly added fields are
7121 -- visible and hence the Derived_Type is always an E_Record_Type.
7122 -- (except that the parent may have its own private fields).
7123 -- For untagged types we preserve the Ekind of the Parent_Base.
7125 if Present (Record_Extension_Part (Type_Def)) then
7126 Set_Ekind (Derived_Type, E_Record_Type);
7128 -- Create internal access types for components with anonymous
7131 if Ada_Version >= Ada_2005 then
7132 Check_Anonymous_Access_Components
7133 (N, Derived_Type, Derived_Type,
7134 Component_List (Record_Extension_Part (Type_Def)));
7138 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7142 -- Indic can either be an N_Identifier if the subtype indication
7143 -- contains no constraint or an N_Subtype_Indication if the subtype
7144 -- indication has a constraint.
7146 Indic := Subtype_Indication (Type_Def);
7147 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
7149 -- Check that the type has visible discriminants. The type may be
7150 -- a private type with unknown discriminants whose full view has
7151 -- discriminants which are invisible.
7153 if Constraint_Present then
7154 if not Has_Discriminants (Parent_Base)
7156 (Has_Unknown_Discriminants (Parent_Base)
7157 and then Is_Private_Type (Parent_Base))
7160 ("invalid constraint: type has no discriminant",
7161 Constraint (Indic));
7163 Constraint_Present := False;
7164 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7166 elsif Is_Constrained (Parent_Type) then
7168 ("invalid constraint: parent type is already constrained",
7169 Constraint (Indic));
7171 Constraint_Present := False;
7172 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7176 -- STEP 0b: If needed, apply transformation given in point 5. above
7178 if not Private_Extension
7179 and then Has_Discriminants (Parent_Type)
7180 and then not Discriminant_Specs
7181 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
7183 -- First, we must analyze the constraint (see comment in point 5.)
7185 if Constraint_Present then
7186 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
7188 if Has_Discriminants (Derived_Type)
7189 and then Has_Private_Declaration (Derived_Type)
7190 and then Present (Discriminant_Constraint (Derived_Type))
7192 -- Verify that constraints of the full view statically match
7193 -- those given in the partial view.
7199 C1 := First_Elmt (New_Discrs);
7200 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
7201 while Present (C1) and then Present (C2) loop
7202 if Fully_Conformant_Expressions (Node (C1), Node (C2))
7204 (Is_OK_Static_Expression (Node (C1))
7206 Is_OK_Static_Expression (Node (C2))
7208 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
7214 "constraint not conformant to previous declaration",
7225 -- Insert and analyze the declaration for the unconstrained base type
7227 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
7230 Make_Full_Type_Declaration (Loc,
7231 Defining_Identifier => New_Base,
7233 Make_Derived_Type_Definition (Loc,
7234 Abstract_Present => Abstract_Present (Type_Def),
7235 Limited_Present => Limited_Present (Type_Def),
7236 Subtype_Indication =>
7237 New_Occurrence_Of (Parent_Base, Loc),
7238 Record_Extension_Part =>
7239 Relocate_Node (Record_Extension_Part (Type_Def)),
7240 Interface_List => Interface_List (Type_Def)));
7242 Set_Parent (New_Decl, Parent (N));
7243 Mark_Rewrite_Insertion (New_Decl);
7244 Insert_Before (N, New_Decl);
7246 -- In the extension case, make sure ancestor is frozen appropriately
7247 -- (see also non-discriminated case below).
7249 if Present (Record_Extension_Part (Type_Def))
7250 or else Is_Interface (Parent_Base)
7252 Freeze_Before (New_Decl, Parent_Type);
7255 -- Note that this call passes False for the Derive_Subps parameter
7256 -- because subprogram derivation is deferred until after creating
7257 -- the subtype (see below).
7260 (New_Decl, Parent_Base, New_Base,
7261 Is_Completion => True, Derive_Subps => False);
7263 -- ??? This needs re-examination to determine whether the
7264 -- above call can simply be replaced by a call to Analyze.
7266 Set_Analyzed (New_Decl);
7268 -- Insert and analyze the declaration for the constrained subtype
7270 if Constraint_Present then
7272 Make_Subtype_Indication (Loc,
7273 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
7274 Constraint => Relocate_Node (Constraint (Indic)));
7278 Constr_List : constant List_Id := New_List;
7283 C := First_Elmt (Discriminant_Constraint (Parent_Type));
7284 while Present (C) loop
7287 -- It is safe here to call New_Copy_Tree since
7288 -- Force_Evaluation was called on each constraint in
7289 -- Build_Discriminant_Constraints.
7291 Append (New_Copy_Tree (Expr), To => Constr_List);
7297 Make_Subtype_Indication (Loc,
7298 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
7300 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
7305 Make_Subtype_Declaration (Loc,
7306 Defining_Identifier => Derived_Type,
7307 Subtype_Indication => New_Indic));
7311 -- Derivation of subprograms must be delayed until the full subtype
7312 -- has been established, to ensure proper overriding of subprograms
7313 -- inherited by full types. If the derivations occurred as part of
7314 -- the call to Build_Derived_Type above, then the check for type
7315 -- conformance would fail because earlier primitive subprograms
7316 -- could still refer to the full type prior the change to the new
7317 -- subtype and hence would not match the new base type created here.
7318 -- Subprograms are not derived, however, when Derive_Subps is False
7319 -- (since otherwise there could be redundant derivations).
7321 if Derive_Subps then
7322 Derive_Subprograms (Parent_Type, Derived_Type);
7325 -- For tagged types the Discriminant_Constraint of the new base itype
7326 -- is inherited from the first subtype so that no subtype conformance
7327 -- problem arise when the first subtype overrides primitive
7328 -- operations inherited by the implicit base type.
7331 Set_Discriminant_Constraint
7332 (New_Base, Discriminant_Constraint (Derived_Type));
7338 -- If we get here Derived_Type will have no discriminants or it will be
7339 -- a discriminated unconstrained base type.
7341 -- STEP 1a: perform preliminary actions/checks for derived tagged types
7345 -- The parent type is frozen for non-private extensions (RM 13.14(7))
7346 -- The declaration of a specific descendant of an interface type
7347 -- freezes the interface type (RM 13.14).
7349 if not Private_Extension or else Is_Interface (Parent_Base) then
7350 Freeze_Before (N, Parent_Type);
7353 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
7354 -- cannot be declared at a deeper level than its parent type is
7355 -- removed. The check on derivation within a generic body is also
7356 -- relaxed, but there's a restriction that a derived tagged type
7357 -- cannot be declared in a generic body if it's derived directly
7358 -- or indirectly from a formal type of that generic.
7360 if Ada_Version >= Ada_2005 then
7361 if Present (Enclosing_Generic_Body (Derived_Type)) then
7363 Ancestor_Type : Entity_Id;
7366 -- Check to see if any ancestor of the derived type is a
7369 Ancestor_Type := Parent_Type;
7370 while not Is_Generic_Type (Ancestor_Type)
7371 and then Etype (Ancestor_Type) /= Ancestor_Type
7373 Ancestor_Type := Etype (Ancestor_Type);
7376 -- If the derived type does have a formal type as an
7377 -- ancestor, then it's an error if the derived type is
7378 -- declared within the body of the generic unit that
7379 -- declares the formal type in its generic formal part. It's
7380 -- sufficient to check whether the ancestor type is declared
7381 -- inside the same generic body as the derived type (such as
7382 -- within a nested generic spec), in which case the
7383 -- derivation is legal. If the formal type is declared
7384 -- outside of that generic body, then it's guaranteed that
7385 -- the derived type is declared within the generic body of
7386 -- the generic unit declaring the formal type.
7388 if Is_Generic_Type (Ancestor_Type)
7389 and then Enclosing_Generic_Body (Ancestor_Type) /=
7390 Enclosing_Generic_Body (Derived_Type)
7393 ("parent type of& must not be descendant of formal type"
7394 & " of an enclosing generic body",
7395 Indic, Derived_Type);
7400 elsif Type_Access_Level (Derived_Type) /=
7401 Type_Access_Level (Parent_Type)
7402 and then not Is_Generic_Type (Derived_Type)
7404 if Is_Controlled (Parent_Type) then
7406 ("controlled type must be declared at the library level",
7410 ("type extension at deeper accessibility level than parent",
7416 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
7420 and then GB /= Enclosing_Generic_Body (Parent_Base)
7423 ("parent type of& must not be outside generic body"
7425 Indic, Derived_Type);
7431 -- Ada 2005 (AI-251)
7433 if Ada_Version >= Ada_2005 and then Is_Tagged then
7435 -- "The declaration of a specific descendant of an interface type
7436 -- freezes the interface type" (RM 13.14).
7441 if Is_Non_Empty_List (Interface_List (Type_Def)) then
7442 Iface := First (Interface_List (Type_Def));
7443 while Present (Iface) loop
7444 Freeze_Before (N, Etype (Iface));
7451 -- STEP 1b : preliminary cleanup of the full view of private types
7453 -- If the type is already marked as having discriminants, then it's the
7454 -- completion of a private type or private extension and we need to
7455 -- retain the discriminants from the partial view if the current
7456 -- declaration has Discriminant_Specifications so that we can verify
7457 -- conformance. However, we must remove any existing components that
7458 -- were inherited from the parent (and attached in Copy_And_Swap)
7459 -- because the full type inherits all appropriate components anyway, and
7460 -- we do not want the partial view's components interfering.
7462 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
7463 Discrim := First_Discriminant (Derived_Type);
7465 Last_Discrim := Discrim;
7466 Next_Discriminant (Discrim);
7467 exit when No (Discrim);
7470 Set_Last_Entity (Derived_Type, Last_Discrim);
7472 -- In all other cases wipe out the list of inherited components (even
7473 -- inherited discriminants), it will be properly rebuilt here.
7476 Set_First_Entity (Derived_Type, Empty);
7477 Set_Last_Entity (Derived_Type, Empty);
7480 -- STEP 1c: Initialize some flags for the Derived_Type
7482 -- The following flags must be initialized here so that
7483 -- Process_Discriminants can check that discriminants of tagged types do
7484 -- not have a default initial value and that access discriminants are
7485 -- only specified for limited records. For completeness, these flags are
7486 -- also initialized along with all the other flags below.
7488 -- AI-419: Limitedness is not inherited from an interface parent, so to
7489 -- be limited in that case the type must be explicitly declared as
7490 -- limited. However, task and protected interfaces are always limited.
7492 if Limited_Present (Type_Def) then
7493 Set_Is_Limited_Record (Derived_Type);
7495 elsif Is_Limited_Record (Parent_Type)
7496 or else (Present (Full_View (Parent_Type))
7497 and then Is_Limited_Record (Full_View (Parent_Type)))
7499 if not Is_Interface (Parent_Type)
7500 or else Is_Synchronized_Interface (Parent_Type)
7501 or else Is_Protected_Interface (Parent_Type)
7502 or else Is_Task_Interface (Parent_Type)
7504 Set_Is_Limited_Record (Derived_Type);
7508 -- STEP 2a: process discriminants of derived type if any
7510 Push_Scope (Derived_Type);
7512 if Discriminant_Specs then
7513 Set_Has_Unknown_Discriminants (Derived_Type, False);
7515 -- The following call initializes fields Has_Discriminants and
7516 -- Discriminant_Constraint, unless we are processing the completion
7517 -- of a private type declaration.
7519 Check_Or_Process_Discriminants (N, Derived_Type);
7521 -- For untagged types, the constraint on the Parent_Type must be
7522 -- present and is used to rename the discriminants.
7524 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
7525 Error_Msg_N ("untagged parent must have discriminants", Indic);
7527 elsif not Is_Tagged and then not Constraint_Present then
7529 ("discriminant constraint needed for derived untagged records",
7532 -- Otherwise the parent subtype must be constrained unless we have a
7533 -- private extension.
7535 elsif not Constraint_Present
7536 and then not Private_Extension
7537 and then not Is_Constrained (Parent_Type)
7540 ("unconstrained type not allowed in this context", Indic);
7542 elsif Constraint_Present then
7543 -- The following call sets the field Corresponding_Discriminant
7544 -- for the discriminants in the Derived_Type.
7546 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
7548 -- For untagged types all new discriminants must rename
7549 -- discriminants in the parent. For private extensions new
7550 -- discriminants cannot rename old ones (implied by [7.3(13)]).
7552 Discrim := First_Discriminant (Derived_Type);
7553 while Present (Discrim) loop
7555 and then No (Corresponding_Discriminant (Discrim))
7558 ("new discriminants must constrain old ones", Discrim);
7560 elsif Private_Extension
7561 and then Present (Corresponding_Discriminant (Discrim))
7564 ("only static constraints allowed for parent"
7565 & " discriminants in the partial view", Indic);
7569 -- If a new discriminant is used in the constraint, then its
7570 -- subtype must be statically compatible with the parent
7571 -- discriminant's subtype (3.7(15)).
7573 if Present (Corresponding_Discriminant (Discrim))
7575 not Subtypes_Statically_Compatible
7577 Etype (Corresponding_Discriminant (Discrim)))
7580 ("subtype must be compatible with parent discriminant",
7584 Next_Discriminant (Discrim);
7587 -- Check whether the constraints of the full view statically
7588 -- match those imposed by the parent subtype [7.3(13)].
7590 if Present (Stored_Constraint (Derived_Type)) then
7595 C1 := First_Elmt (Discs);
7596 C2 := First_Elmt (Stored_Constraint (Derived_Type));
7597 while Present (C1) and then Present (C2) loop
7599 Fully_Conformant_Expressions (Node (C1), Node (C2))
7602 ("not conformant with previous declaration",
7613 -- STEP 2b: No new discriminants, inherit discriminants if any
7616 if Private_Extension then
7617 Set_Has_Unknown_Discriminants
7619 Has_Unknown_Discriminants (Parent_Type)
7620 or else Unknown_Discriminants_Present (N));
7622 -- The partial view of the parent may have unknown discriminants,
7623 -- but if the full view has discriminants and the parent type is
7624 -- in scope they must be inherited.
7626 elsif Has_Unknown_Discriminants (Parent_Type)
7628 (not Has_Discriminants (Parent_Type)
7629 or else not In_Open_Scopes (Scope (Parent_Type)))
7631 Set_Has_Unknown_Discriminants (Derived_Type);
7634 if not Has_Unknown_Discriminants (Derived_Type)
7635 and then not Has_Unknown_Discriminants (Parent_Base)
7636 and then Has_Discriminants (Parent_Type)
7638 Inherit_Discrims := True;
7639 Set_Has_Discriminants
7640 (Derived_Type, True);
7641 Set_Discriminant_Constraint
7642 (Derived_Type, Discriminant_Constraint (Parent_Base));
7645 -- The following test is true for private types (remember
7646 -- transformation 5. is not applied to those) and in an error
7649 if Constraint_Present then
7650 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
7653 -- For now mark a new derived type as constrained only if it has no
7654 -- discriminants. At the end of Build_Derived_Record_Type we properly
7655 -- set this flag in the case of private extensions. See comments in
7656 -- point 9. just before body of Build_Derived_Record_Type.
7660 not (Inherit_Discrims
7661 or else Has_Unknown_Discriminants (Derived_Type)));
7664 -- STEP 3: initialize fields of derived type
7666 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
7667 Set_Stored_Constraint (Derived_Type, No_Elist);
7669 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
7670 -- but cannot be interfaces
7672 if not Private_Extension
7673 and then Ekind (Derived_Type) /= E_Private_Type
7674 and then Ekind (Derived_Type) /= E_Limited_Private_Type
7676 if Interface_Present (Type_Def) then
7677 Analyze_Interface_Declaration (Derived_Type, Type_Def);
7680 Set_Interfaces (Derived_Type, No_Elist);
7683 -- Fields inherited from the Parent_Type
7686 (Derived_Type, Einfo.Discard_Names (Parent_Type));
7687 Set_Has_Specified_Layout
7688 (Derived_Type, Has_Specified_Layout (Parent_Type));
7689 Set_Is_Limited_Composite
7690 (Derived_Type, Is_Limited_Composite (Parent_Type));
7691 Set_Is_Private_Composite
7692 (Derived_Type, Is_Private_Composite (Parent_Type));
7694 -- Fields inherited from the Parent_Base
7696 Set_Has_Controlled_Component
7697 (Derived_Type, Has_Controlled_Component (Parent_Base));
7698 Set_Has_Non_Standard_Rep
7699 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7700 Set_Has_Primitive_Operations
7701 (Derived_Type, Has_Primitive_Operations (Parent_Base));
7703 -- Fields inherited from the Parent_Base in the non-private case
7705 if Ekind (Derived_Type) = E_Record_Type then
7706 Set_Has_Complex_Representation
7707 (Derived_Type, Has_Complex_Representation (Parent_Base));
7710 -- Fields inherited from the Parent_Base for record types
7712 if Is_Record_Type (Derived_Type) then
7714 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7715 -- Parent_Base can be a private type or private extension.
7717 if Present (Full_View (Parent_Base)) then
7718 Set_OK_To_Reorder_Components
7720 OK_To_Reorder_Components (Full_View (Parent_Base)));
7721 Set_Reverse_Bit_Order
7722 (Derived_Type, Reverse_Bit_Order (Full_View (Parent_Base)));
7724 Set_OK_To_Reorder_Components
7725 (Derived_Type, OK_To_Reorder_Components (Parent_Base));
7726 Set_Reverse_Bit_Order
7727 (Derived_Type, Reverse_Bit_Order (Parent_Base));
7731 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7733 if not Is_Controlled (Parent_Type) then
7734 Set_Finalize_Storage_Only
7735 (Derived_Type, Finalize_Storage_Only (Parent_Type));
7738 -- Set fields for private derived types
7740 if Is_Private_Type (Derived_Type) then
7741 Set_Depends_On_Private (Derived_Type, True);
7742 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7744 -- Inherit fields from non private record types. If this is the
7745 -- completion of a derivation from a private type, the parent itself
7746 -- is private, and the attributes come from its full view, which must
7750 if Is_Private_Type (Parent_Base)
7751 and then not Is_Record_Type (Parent_Base)
7753 Set_Component_Alignment
7754 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
7756 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
7758 Set_Component_Alignment
7759 (Derived_Type, Component_Alignment (Parent_Base));
7761 (Derived_Type, C_Pass_By_Copy (Parent_Base));
7765 -- Set fields for tagged types
7768 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
7770 -- All tagged types defined in Ada.Finalization are controlled
7772 if Chars (Scope (Derived_Type)) = Name_Finalization
7773 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
7774 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
7776 Set_Is_Controlled (Derived_Type);
7778 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
7781 -- Minor optimization: there is no need to generate the class-wide
7782 -- entity associated with an underlying record view.
7784 if not Is_Underlying_Record_View (Derived_Type) then
7785 Make_Class_Wide_Type (Derived_Type);
7788 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
7790 if Has_Discriminants (Derived_Type)
7791 and then Constraint_Present
7793 Set_Stored_Constraint
7794 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
7797 if Ada_Version >= Ada_2005 then
7799 Ifaces_List : Elist_Id;
7802 -- Checks rules 3.9.4 (13/2 and 14/2)
7804 if Comes_From_Source (Derived_Type)
7805 and then not Is_Private_Type (Derived_Type)
7806 and then Is_Interface (Parent_Type)
7807 and then not Is_Interface (Derived_Type)
7809 if Is_Task_Interface (Parent_Type) then
7811 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
7814 elsif Is_Protected_Interface (Parent_Type) then
7816 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
7821 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
7823 Check_Interfaces (N, Type_Def);
7825 -- Ada 2005 (AI-251): Collect the list of progenitors that are
7826 -- not already in the parents.
7830 Ifaces_List => Ifaces_List,
7831 Exclude_Parents => True);
7833 Set_Interfaces (Derived_Type, Ifaces_List);
7835 -- If the derived type is the anonymous type created for
7836 -- a declaration whose parent has a constraint, propagate
7837 -- the interface list to the source type. This must be done
7838 -- prior to the completion of the analysis of the source type
7839 -- because the components in the extension may contain current
7840 -- instances whose legality depends on some ancestor.
7842 if Is_Itype (Derived_Type) then
7844 Def : constant Node_Id :=
7845 Associated_Node_For_Itype (Derived_Type);
7848 and then Nkind (Def) = N_Full_Type_Declaration
7851 (Defining_Identifier (Def), Ifaces_List);
7859 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
7860 Set_Has_Non_Standard_Rep
7861 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7864 -- STEP 4: Inherit components from the parent base and constrain them.
7865 -- Apply the second transformation described in point 6. above.
7867 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
7868 or else not Has_Discriminants (Parent_Type)
7869 or else not Is_Constrained (Parent_Type)
7873 Constrs := Discriminant_Constraint (Parent_Type);
7878 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
7880 -- STEP 5a: Copy the parent record declaration for untagged types
7882 if not Is_Tagged then
7884 -- Discriminant_Constraint (Derived_Type) has been properly
7885 -- constructed. Save it and temporarily set it to Empty because we
7886 -- do not want the call to New_Copy_Tree below to mess this list.
7888 if Has_Discriminants (Derived_Type) then
7889 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
7890 Set_Discriminant_Constraint (Derived_Type, No_Elist);
7892 Save_Discr_Constr := No_Elist;
7895 -- Save the Etype field of Derived_Type. It is correctly set now,
7896 -- but the call to New_Copy tree may remap it to point to itself,
7897 -- which is not what we want. Ditto for the Next_Entity field.
7899 Save_Etype := Etype (Derived_Type);
7900 Save_Next_Entity := Next_Entity (Derived_Type);
7902 -- Assoc_List maps all stored discriminants in the Parent_Base to
7903 -- stored discriminants in the Derived_Type. It is fundamental that
7904 -- no types or itypes with discriminants other than the stored
7905 -- discriminants appear in the entities declared inside
7906 -- Derived_Type, since the back end cannot deal with it.
7910 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
7912 -- Restore the fields saved prior to the New_Copy_Tree call
7913 -- and compute the stored constraint.
7915 Set_Etype (Derived_Type, Save_Etype);
7916 Set_Next_Entity (Derived_Type, Save_Next_Entity);
7918 if Has_Discriminants (Derived_Type) then
7919 Set_Discriminant_Constraint
7920 (Derived_Type, Save_Discr_Constr);
7921 Set_Stored_Constraint
7922 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
7923 Replace_Components (Derived_Type, New_Decl);
7924 Set_Has_Implicit_Dereference
7925 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
7928 -- Insert the new derived type declaration
7930 Rewrite (N, New_Decl);
7932 -- STEP 5b: Complete the processing for record extensions in generics
7934 -- There is no completion for record extensions declared in the
7935 -- parameter part of a generic, so we need to complete processing for
7936 -- these generic record extensions here. The Record_Type_Definition call
7937 -- will change the Ekind of the components from E_Void to E_Component.
7939 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
7940 Record_Type_Definition (Empty, Derived_Type);
7942 -- STEP 5c: Process the record extension for non private tagged types
7944 elsif not Private_Extension then
7946 -- Add the _parent field in the derived type
7948 Expand_Record_Extension (Derived_Type, Type_Def);
7950 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
7951 -- implemented interfaces if we are in expansion mode
7954 and then Has_Interfaces (Derived_Type)
7956 Add_Interface_Tag_Components (N, Derived_Type);
7959 -- Analyze the record extension
7961 Record_Type_Definition
7962 (Record_Extension_Part (Type_Def), Derived_Type);
7967 -- Nothing else to do if there is an error in the derivation.
7968 -- An unusual case: the full view may be derived from a type in an
7969 -- instance, when the partial view was used illegally as an actual
7970 -- in that instance, leading to a circular definition.
7972 if Etype (Derived_Type) = Any_Type
7973 or else Etype (Parent_Type) = Derived_Type
7978 -- Set delayed freeze and then derive subprograms, we need to do
7979 -- this in this order so that derived subprograms inherit the
7980 -- derived freeze if necessary.
7982 Set_Has_Delayed_Freeze (Derived_Type);
7984 if Derive_Subps then
7985 Derive_Subprograms (Parent_Type, Derived_Type);
7988 -- If we have a private extension which defines a constrained derived
7989 -- type mark as constrained here after we have derived subprograms. See
7990 -- comment on point 9. just above the body of Build_Derived_Record_Type.
7992 if Private_Extension and then Inherit_Discrims then
7993 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
7994 Set_Is_Constrained (Derived_Type, True);
7995 Set_Discriminant_Constraint (Derived_Type, Discs);
7997 elsif Is_Constrained (Parent_Type) then
7999 (Derived_Type, True);
8000 Set_Discriminant_Constraint
8001 (Derived_Type, Discriminant_Constraint (Parent_Type));
8005 -- Update the class-wide type, which shares the now-completed entity
8006 -- list with its specific type. In case of underlying record views,
8007 -- we do not generate the corresponding class wide entity.
8010 and then not Is_Underlying_Record_View (Derived_Type)
8013 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
8015 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
8017 end Build_Derived_Record_Type;
8019 ------------------------
8020 -- Build_Derived_Type --
8021 ------------------------
8023 procedure Build_Derived_Type
8025 Parent_Type : Entity_Id;
8026 Derived_Type : Entity_Id;
8027 Is_Completion : Boolean;
8028 Derive_Subps : Boolean := True)
8030 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
8033 -- Set common attributes
8035 Set_Scope (Derived_Type, Current_Scope);
8037 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8038 Set_Etype (Derived_Type, Parent_Base);
8039 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
8041 Set_Size_Info (Derived_Type, Parent_Type);
8042 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
8043 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
8044 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
8046 -- If the parent type is a private subtype, the convention on the base
8047 -- type may be set in the private part, and not propagated to the
8048 -- subtype until later, so we obtain the convention from the base type.
8050 Set_Convention (Derived_Type, Convention (Parent_Base));
8052 -- Propagate invariant information. The new type has invariants if
8053 -- they are inherited from the parent type, and these invariants can
8054 -- be further inherited, so both flags are set.
8056 if Has_Inheritable_Invariants (Parent_Type) then
8057 Set_Has_Inheritable_Invariants (Derived_Type);
8058 Set_Has_Invariants (Derived_Type);
8061 -- We similarly inherit predicates
8063 if Has_Predicates (Parent_Type) then
8064 Set_Has_Predicates (Derived_Type);
8067 -- The derived type inherits the representation clauses of the parent.
8068 -- However, for a private type that is completed by a derivation, there
8069 -- may be operation attributes that have been specified already (stream
8070 -- attributes and External_Tag) and those must be provided. Finally,
8071 -- if the partial view is a private extension, the representation items
8072 -- of the parent have been inherited already, and should not be chained
8073 -- twice to the derived type.
8075 if Is_Tagged_Type (Parent_Type)
8076 and then Present (First_Rep_Item (Derived_Type))
8078 -- The existing items are either operational items or items inherited
8079 -- from a private extension declaration.
8083 -- Used to iterate over representation items of the derived type
8086 -- Last representation item of the (non-empty) representation
8087 -- item list of the derived type.
8089 Found : Boolean := False;
8092 Rep := First_Rep_Item (Derived_Type);
8094 while Present (Rep) loop
8095 if Rep = First_Rep_Item (Parent_Type) then
8100 Rep := Next_Rep_Item (Rep);
8102 if Present (Rep) then
8108 -- Here if we either encountered the parent type's first rep
8109 -- item on the derived type's rep item list (in which case
8110 -- Found is True, and we have nothing else to do), or if we
8111 -- reached the last rep item of the derived type, which is
8112 -- Last_Rep, in which case we further chain the parent type's
8113 -- rep items to those of the derived type.
8116 Set_Next_Rep_Item (Last_Rep, First_Rep_Item (Parent_Type));
8121 Set_First_Rep_Item (Derived_Type, First_Rep_Item (Parent_Type));
8124 case Ekind (Parent_Type) is
8125 when Numeric_Kind =>
8126 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
8129 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
8133 | Class_Wide_Kind =>
8134 Build_Derived_Record_Type
8135 (N, Parent_Type, Derived_Type, Derive_Subps);
8138 when Enumeration_Kind =>
8139 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
8142 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
8144 when Incomplete_Or_Private_Kind =>
8145 Build_Derived_Private_Type
8146 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
8148 -- For discriminated types, the derivation includes deriving
8149 -- primitive operations. For others it is done below.
8151 if Is_Tagged_Type (Parent_Type)
8152 or else Has_Discriminants (Parent_Type)
8153 or else (Present (Full_View (Parent_Type))
8154 and then Has_Discriminants (Full_View (Parent_Type)))
8159 when Concurrent_Kind =>
8160 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
8163 raise Program_Error;
8166 if Etype (Derived_Type) = Any_Type then
8170 -- Set delayed freeze and then derive subprograms, we need to do this
8171 -- in this order so that derived subprograms inherit the derived freeze
8174 Set_Has_Delayed_Freeze (Derived_Type);
8175 if Derive_Subps then
8176 Derive_Subprograms (Parent_Type, Derived_Type);
8179 Set_Has_Primitive_Operations
8180 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
8181 end Build_Derived_Type;
8183 -----------------------
8184 -- Build_Discriminal --
8185 -----------------------
8187 procedure Build_Discriminal (Discrim : Entity_Id) is
8188 D_Minal : Entity_Id;
8189 CR_Disc : Entity_Id;
8192 -- A discriminal has the same name as the discriminant
8194 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8196 Set_Ekind (D_Minal, E_In_Parameter);
8197 Set_Mechanism (D_Minal, Default_Mechanism);
8198 Set_Etype (D_Minal, Etype (Discrim));
8199 Set_Scope (D_Minal, Current_Scope);
8201 Set_Discriminal (Discrim, D_Minal);
8202 Set_Discriminal_Link (D_Minal, Discrim);
8204 -- For task types, build at once the discriminants of the corresponding
8205 -- record, which are needed if discriminants are used in entry defaults
8206 -- and in family bounds.
8208 if Is_Concurrent_Type (Current_Scope)
8209 or else Is_Limited_Type (Current_Scope)
8211 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8213 Set_Ekind (CR_Disc, E_In_Parameter);
8214 Set_Mechanism (CR_Disc, Default_Mechanism);
8215 Set_Etype (CR_Disc, Etype (Discrim));
8216 Set_Scope (CR_Disc, Current_Scope);
8217 Set_Discriminal_Link (CR_Disc, Discrim);
8218 Set_CR_Discriminant (Discrim, CR_Disc);
8220 end Build_Discriminal;
8222 ------------------------------------
8223 -- Build_Discriminant_Constraints --
8224 ------------------------------------
8226 function Build_Discriminant_Constraints
8229 Derived_Def : Boolean := False) return Elist_Id
8231 C : constant Node_Id := Constraint (Def);
8232 Nb_Discr : constant Nat := Number_Discriminants (T);
8234 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
8235 -- Saves the expression corresponding to a given discriminant in T
8237 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
8238 -- Return the Position number within array Discr_Expr of a discriminant
8239 -- D within the discriminant list of the discriminated type T.
8245 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
8249 Disc := First_Discriminant (T);
8250 for J in Discr_Expr'Range loop
8255 Next_Discriminant (Disc);
8258 -- Note: Since this function is called on discriminants that are
8259 -- known to belong to the discriminated type, falling through the
8260 -- loop with no match signals an internal compiler error.
8262 raise Program_Error;
8265 -- Declarations local to Build_Discriminant_Constraints
8269 Elist : constant Elist_Id := New_Elmt_List;
8277 Discrim_Present : Boolean := False;
8279 -- Start of processing for Build_Discriminant_Constraints
8282 -- The following loop will process positional associations only.
8283 -- For a positional association, the (single) discriminant is
8284 -- implicitly specified by position, in textual order (RM 3.7.2).
8286 Discr := First_Discriminant (T);
8287 Constr := First (Constraints (C));
8288 for D in Discr_Expr'Range loop
8289 exit when Nkind (Constr) = N_Discriminant_Association;
8292 Error_Msg_N ("too few discriminants given in constraint", C);
8293 return New_Elmt_List;
8295 elsif Nkind (Constr) = N_Range
8296 or else (Nkind (Constr) = N_Attribute_Reference
8298 Attribute_Name (Constr) = Name_Range)
8301 ("a range is not a valid discriminant constraint", Constr);
8302 Discr_Expr (D) := Error;
8305 Analyze_And_Resolve (Constr, Base_Type (Etype (Discr)));
8306 Discr_Expr (D) := Constr;
8309 Next_Discriminant (Discr);
8313 if No (Discr) and then Present (Constr) then
8314 Error_Msg_N ("too many discriminants given in constraint", Constr);
8315 return New_Elmt_List;
8318 -- Named associations can be given in any order, but if both positional
8319 -- and named associations are used in the same discriminant constraint,
8320 -- then positional associations must occur first, at their normal
8321 -- position. Hence once a named association is used, the rest of the
8322 -- discriminant constraint must use only named associations.
8324 while Present (Constr) loop
8326 -- Positional association forbidden after a named association
8328 if Nkind (Constr) /= N_Discriminant_Association then
8329 Error_Msg_N ("positional association follows named one", Constr);
8330 return New_Elmt_List;
8332 -- Otherwise it is a named association
8335 -- E records the type of the discriminants in the named
8336 -- association. All the discriminants specified in the same name
8337 -- association must have the same type.
8341 -- Search the list of discriminants in T to see if the simple name
8342 -- given in the constraint matches any of them.
8344 Id := First (Selector_Names (Constr));
8345 while Present (Id) loop
8348 -- If Original_Discriminant is present, we are processing a
8349 -- generic instantiation and this is an instance node. We need
8350 -- to find the name of the corresponding discriminant in the
8351 -- actual record type T and not the name of the discriminant in
8352 -- the generic formal. Example:
8355 -- type G (D : int) is private;
8357 -- subtype W is G (D => 1);
8359 -- type Rec (X : int) is record ... end record;
8360 -- package Q is new P (G => Rec);
8362 -- At the point of the instantiation, formal type G is Rec
8363 -- and therefore when reanalyzing "subtype W is G (D => 1);"
8364 -- which really looks like "subtype W is Rec (D => 1);" at
8365 -- the point of instantiation, we want to find the discriminant
8366 -- that corresponds to D in Rec, i.e. X.
8368 if Present (Original_Discriminant (Id))
8369 and then In_Instance
8371 Discr := Find_Corresponding_Discriminant (Id, T);
8375 Discr := First_Discriminant (T);
8376 while Present (Discr) loop
8377 if Chars (Discr) = Chars (Id) then
8382 Next_Discriminant (Discr);
8386 Error_Msg_N ("& does not match any discriminant", Id);
8387 return New_Elmt_List;
8389 -- If the parent type is a generic formal, preserve the
8390 -- name of the discriminant for subsequent instances.
8391 -- see comment at the beginning of this if statement.
8393 elsif Is_Generic_Type (Root_Type (T)) then
8394 Set_Original_Discriminant (Id, Discr);
8398 Position := Pos_Of_Discr (T, Discr);
8400 if Present (Discr_Expr (Position)) then
8401 Error_Msg_N ("duplicate constraint for discriminant&", Id);
8404 -- Each discriminant specified in the same named association
8405 -- must be associated with a separate copy of the
8406 -- corresponding expression.
8408 if Present (Next (Id)) then
8409 Expr := New_Copy_Tree (Expression (Constr));
8410 Set_Parent (Expr, Parent (Expression (Constr)));
8412 Expr := Expression (Constr);
8415 Discr_Expr (Position) := Expr;
8416 Analyze_And_Resolve (Expr, Base_Type (Etype (Discr)));
8419 -- A discriminant association with more than one discriminant
8420 -- name is only allowed if the named discriminants are all of
8421 -- the same type (RM 3.7.1(8)).
8424 E := Base_Type (Etype (Discr));
8426 elsif Base_Type (Etype (Discr)) /= E then
8428 ("all discriminants in an association " &
8429 "must have the same type", Id);
8439 -- A discriminant constraint must provide exactly one value for each
8440 -- discriminant of the type (RM 3.7.1(8)).
8442 for J in Discr_Expr'Range loop
8443 if No (Discr_Expr (J)) then
8444 Error_Msg_N ("too few discriminants given in constraint", C);
8445 return New_Elmt_List;
8449 -- Determine if there are discriminant expressions in the constraint
8451 for J in Discr_Expr'Range loop
8452 if Denotes_Discriminant
8453 (Discr_Expr (J), Check_Concurrent => True)
8455 Discrim_Present := True;
8459 -- Build an element list consisting of the expressions given in the
8460 -- discriminant constraint and apply the appropriate checks. The list
8461 -- is constructed after resolving any named discriminant associations
8462 -- and therefore the expressions appear in the textual order of the
8465 Discr := First_Discriminant (T);
8466 for J in Discr_Expr'Range loop
8467 if Discr_Expr (J) /= Error then
8468 Append_Elmt (Discr_Expr (J), Elist);
8470 -- If any of the discriminant constraints is given by a
8471 -- discriminant and we are in a derived type declaration we
8472 -- have a discriminant renaming. Establish link between new
8473 -- and old discriminant.
8475 if Denotes_Discriminant (Discr_Expr (J)) then
8477 Set_Corresponding_Discriminant
8478 (Entity (Discr_Expr (J)), Discr);
8481 -- Force the evaluation of non-discriminant expressions.
8482 -- If we have found a discriminant in the constraint 3.4(26)
8483 -- and 3.8(18) demand that no range checks are performed are
8484 -- after evaluation. If the constraint is for a component
8485 -- definition that has a per-object constraint, expressions are
8486 -- evaluated but not checked either. In all other cases perform
8490 if Discrim_Present then
8493 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
8495 Has_Per_Object_Constraint
8496 (Defining_Identifier (Parent (Parent (Def))))
8500 elsif Is_Access_Type (Etype (Discr)) then
8501 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
8504 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
8507 Force_Evaluation (Discr_Expr (J));
8510 -- Check that the designated type of an access discriminant's
8511 -- expression is not a class-wide type unless the discriminant's
8512 -- designated type is also class-wide.
8514 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
8515 and then not Is_Class_Wide_Type
8516 (Designated_Type (Etype (Discr)))
8517 and then Etype (Discr_Expr (J)) /= Any_Type
8518 and then Is_Class_Wide_Type
8519 (Designated_Type (Etype (Discr_Expr (J))))
8521 Wrong_Type (Discr_Expr (J), Etype (Discr));
8523 elsif Is_Access_Type (Etype (Discr))
8524 and then not Is_Access_Constant (Etype (Discr))
8525 and then Is_Access_Type (Etype (Discr_Expr (J)))
8526 and then Is_Access_Constant (Etype (Discr_Expr (J)))
8529 ("constraint for discriminant& must be access to variable",
8534 Next_Discriminant (Discr);
8538 end Build_Discriminant_Constraints;
8540 ---------------------------------
8541 -- Build_Discriminated_Subtype --
8542 ---------------------------------
8544 procedure Build_Discriminated_Subtype
8548 Related_Nod : Node_Id;
8549 For_Access : Boolean := False)
8551 Has_Discrs : constant Boolean := Has_Discriminants (T);
8552 Constrained : constant Boolean :=
8554 and then not Is_Empty_Elmt_List (Elist)
8555 and then not Is_Class_Wide_Type (T))
8556 or else Is_Constrained (T);
8559 if Ekind (T) = E_Record_Type then
8561 Set_Ekind (Def_Id, E_Private_Subtype);
8562 Set_Is_For_Access_Subtype (Def_Id, True);
8564 Set_Ekind (Def_Id, E_Record_Subtype);
8567 -- Inherit preelaboration flag from base, for types for which it
8568 -- may have been set: records, private types, protected types.
8570 Set_Known_To_Have_Preelab_Init
8571 (Def_Id, Known_To_Have_Preelab_Init (T));
8573 elsif Ekind (T) = E_Task_Type then
8574 Set_Ekind (Def_Id, E_Task_Subtype);
8576 elsif Ekind (T) = E_Protected_Type then
8577 Set_Ekind (Def_Id, E_Protected_Subtype);
8578 Set_Known_To_Have_Preelab_Init
8579 (Def_Id, Known_To_Have_Preelab_Init (T));
8581 elsif Is_Private_Type (T) then
8582 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
8583 Set_Known_To_Have_Preelab_Init
8584 (Def_Id, Known_To_Have_Preelab_Init (T));
8586 elsif Is_Class_Wide_Type (T) then
8587 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
8590 -- Incomplete type. Attach subtype to list of dependents, to be
8591 -- completed with full view of parent type, unless is it the
8592 -- designated subtype of a record component within an init_proc.
8593 -- This last case arises for a component of an access type whose
8594 -- designated type is incomplete (e.g. a Taft Amendment type).
8595 -- The designated subtype is within an inner scope, and needs no
8596 -- elaboration, because only the access type is needed in the
8597 -- initialization procedure.
8599 Set_Ekind (Def_Id, Ekind (T));
8601 if For_Access and then Within_Init_Proc then
8604 Append_Elmt (Def_Id, Private_Dependents (T));
8608 Set_Etype (Def_Id, T);
8609 Init_Size_Align (Def_Id);
8610 Set_Has_Discriminants (Def_Id, Has_Discrs);
8611 Set_Is_Constrained (Def_Id, Constrained);
8613 Set_First_Entity (Def_Id, First_Entity (T));
8614 Set_Last_Entity (Def_Id, Last_Entity (T));
8615 Set_Has_Implicit_Dereference
8616 (Def_Id, Has_Implicit_Dereference (T));
8618 -- If the subtype is the completion of a private declaration, there may
8619 -- have been representation clauses for the partial view, and they must
8620 -- be preserved. Build_Derived_Type chains the inherited clauses with
8621 -- the ones appearing on the extension. If this comes from a subtype
8622 -- declaration, all clauses are inherited.
8624 if No (First_Rep_Item (Def_Id)) then
8625 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
8628 if Is_Tagged_Type (T) then
8629 Set_Is_Tagged_Type (Def_Id);
8630 Make_Class_Wide_Type (Def_Id);
8633 Set_Stored_Constraint (Def_Id, No_Elist);
8636 Set_Discriminant_Constraint (Def_Id, Elist);
8637 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
8640 if Is_Tagged_Type (T) then
8642 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
8643 -- concurrent record type (which has the list of primitive
8646 if Ada_Version >= Ada_2005
8647 and then Is_Concurrent_Type (T)
8649 Set_Corresponding_Record_Type (Def_Id,
8650 Corresponding_Record_Type (T));
8652 Set_Direct_Primitive_Operations (Def_Id,
8653 Direct_Primitive_Operations (T));
8656 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
8659 -- Subtypes introduced by component declarations do not need to be
8660 -- marked as delayed, and do not get freeze nodes, because the semantics
8661 -- verifies that the parents of the subtypes are frozen before the
8662 -- enclosing record is frozen.
8664 if not Is_Type (Scope (Def_Id)) then
8665 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
8667 if Is_Private_Type (T)
8668 and then Present (Full_View (T))
8670 Conditional_Delay (Def_Id, Full_View (T));
8672 Conditional_Delay (Def_Id, T);
8676 if Is_Record_Type (T) then
8677 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
8680 and then not Is_Empty_Elmt_List (Elist)
8681 and then not For_Access
8683 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
8684 elsif not For_Access then
8685 Set_Cloned_Subtype (Def_Id, T);
8688 end Build_Discriminated_Subtype;
8690 ---------------------------
8691 -- Build_Itype_Reference --
8692 ---------------------------
8694 procedure Build_Itype_Reference
8698 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
8701 -- Itype references are only created for use by the back-end
8703 if Inside_A_Generic then
8706 Set_Itype (IR, Ityp);
8707 Insert_After (Nod, IR);
8709 end Build_Itype_Reference;
8711 ------------------------
8712 -- Build_Scalar_Bound --
8713 ------------------------
8715 function Build_Scalar_Bound
8718 Der_T : Entity_Id) return Node_Id
8720 New_Bound : Entity_Id;
8723 -- Note: not clear why this is needed, how can the original bound
8724 -- be unanalyzed at this point? and if it is, what business do we
8725 -- have messing around with it? and why is the base type of the
8726 -- parent type the right type for the resolution. It probably is
8727 -- not! It is OK for the new bound we are creating, but not for
8728 -- the old one??? Still if it never happens, no problem!
8730 Analyze_And_Resolve (Bound, Base_Type (Par_T));
8732 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
8733 New_Bound := New_Copy (Bound);
8734 Set_Etype (New_Bound, Der_T);
8735 Set_Analyzed (New_Bound);
8737 elsif Is_Entity_Name (Bound) then
8738 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
8740 -- The following is almost certainly wrong. What business do we have
8741 -- relocating a node (Bound) that is presumably still attached to
8742 -- the tree elsewhere???
8745 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
8748 Set_Etype (New_Bound, Der_T);
8750 end Build_Scalar_Bound;
8752 --------------------------------
8753 -- Build_Underlying_Full_View --
8754 --------------------------------
8756 procedure Build_Underlying_Full_View
8761 Loc : constant Source_Ptr := Sloc (N);
8762 Subt : constant Entity_Id :=
8763 Make_Defining_Identifier
8764 (Loc, New_External_Name (Chars (Typ), 'S'));
8771 procedure Set_Discriminant_Name (Id : Node_Id);
8772 -- If the derived type has discriminants, they may rename discriminants
8773 -- of the parent. When building the full view of the parent, we need to
8774 -- recover the names of the original discriminants if the constraint is
8775 -- given by named associations.
8777 ---------------------------
8778 -- Set_Discriminant_Name --
8779 ---------------------------
8781 procedure Set_Discriminant_Name (Id : Node_Id) is
8785 Set_Original_Discriminant (Id, Empty);
8787 if Has_Discriminants (Typ) then
8788 Disc := First_Discriminant (Typ);
8789 while Present (Disc) loop
8790 if Chars (Disc) = Chars (Id)
8791 and then Present (Corresponding_Discriminant (Disc))
8793 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
8795 Next_Discriminant (Disc);
8798 end Set_Discriminant_Name;
8800 -- Start of processing for Build_Underlying_Full_View
8803 if Nkind (N) = N_Full_Type_Declaration then
8804 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
8806 elsif Nkind (N) = N_Subtype_Declaration then
8807 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
8809 elsif Nkind (N) = N_Component_Declaration then
8812 (Constraint (Subtype_Indication (Component_Definition (N))));
8815 raise Program_Error;
8818 C := First (Constraints (Constr));
8819 while Present (C) loop
8820 if Nkind (C) = N_Discriminant_Association then
8821 Id := First (Selector_Names (C));
8822 while Present (Id) loop
8823 Set_Discriminant_Name (Id);
8832 Make_Subtype_Declaration (Loc,
8833 Defining_Identifier => Subt,
8834 Subtype_Indication =>
8835 Make_Subtype_Indication (Loc,
8836 Subtype_Mark => New_Reference_To (Par, Loc),
8837 Constraint => New_Copy_Tree (Constr)));
8839 -- If this is a component subtype for an outer itype, it is not
8840 -- a list member, so simply set the parent link for analysis: if
8841 -- the enclosing type does not need to be in a declarative list,
8842 -- neither do the components.
8844 if Is_List_Member (N)
8845 and then Nkind (N) /= N_Component_Declaration
8847 Insert_Before (N, Indic);
8849 Set_Parent (Indic, Parent (N));
8853 Set_Underlying_Full_View (Typ, Full_View (Subt));
8854 end Build_Underlying_Full_View;
8856 -------------------------------
8857 -- Check_Abstract_Overriding --
8858 -------------------------------
8860 procedure Check_Abstract_Overriding (T : Entity_Id) is
8861 Alias_Subp : Entity_Id;
8867 procedure Check_Pragma_Implemented (Subp : Entity_Id);
8868 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
8869 -- which has pragma Implemented already set. Check whether Subp's entity
8870 -- kind conforms to the implementation kind of the overridden routine.
8872 procedure Check_Pragma_Implemented
8874 Iface_Subp : Entity_Id);
8875 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
8876 -- Iface_Subp and both entities have pragma Implemented already set on
8877 -- them. Check whether the two implementation kinds are conforming.
8879 procedure Inherit_Pragma_Implemented
8881 Iface_Subp : Entity_Id);
8882 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
8883 -- subprogram Iface_Subp which has been marked by pragma Implemented.
8884 -- Propagate the implementation kind of Iface_Subp to Subp.
8886 ------------------------------
8887 -- Check_Pragma_Implemented --
8888 ------------------------------
8890 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
8891 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
8892 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
8893 Contr_Typ : Entity_Id;
8896 -- Subp must have an alias since it is a hidden entity used to link
8897 -- an interface subprogram to its overriding counterpart.
8899 pragma Assert (Present (Alias (Subp)));
8901 -- Extract the type of the controlling formal
8903 Contr_Typ := Etype (First_Formal (Alias (Subp)));
8905 if Is_Concurrent_Record_Type (Contr_Typ) then
8906 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
8909 -- An interface subprogram whose implementation kind is By_Entry must
8910 -- be implemented by an entry.
8912 if Impl_Kind = Name_By_Entry
8913 and then Ekind (Wrapped_Entity (Alias (Subp))) /= E_Entry
8915 Error_Msg_Node_2 := Iface_Alias;
8917 ("type & must implement abstract subprogram & with an entry",
8918 Alias (Subp), Contr_Typ);
8920 elsif Impl_Kind = Name_By_Protected_Procedure then
8922 -- An interface subprogram whose implementation kind is By_
8923 -- Protected_Procedure cannot be implemented by a primitive
8924 -- procedure of a task type.
8926 if Ekind (Contr_Typ) /= E_Protected_Type then
8927 Error_Msg_Node_2 := Contr_Typ;
8929 ("interface subprogram & cannot be implemented by a " &
8930 "primitive procedure of task type &", Alias (Subp),
8933 -- An interface subprogram whose implementation kind is By_
8934 -- Protected_Procedure must be implemented by a procedure.
8936 elsif Is_Primitive_Wrapper (Alias (Subp))
8937 and then Ekind (Wrapped_Entity (Alias (Subp))) /= E_Procedure
8939 Error_Msg_Node_2 := Iface_Alias;
8941 ("type & must implement abstract subprogram & with a " &
8942 "procedure", Alias (Subp), Contr_Typ);
8945 end Check_Pragma_Implemented;
8947 ------------------------------
8948 -- Check_Pragma_Implemented --
8949 ------------------------------
8951 procedure Check_Pragma_Implemented
8953 Iface_Subp : Entity_Id)
8955 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
8956 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
8959 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
8960 -- and overriding subprogram are different. In general this is an
8961 -- error except when the implementation kind of the overridden
8962 -- subprograms is By_Any.
8964 if Iface_Kind /= Subp_Kind
8965 and then Iface_Kind /= Name_By_Any
8967 if Iface_Kind = Name_By_Entry then
8969 ("incompatible implementation kind, overridden subprogram " &
8970 "is marked By_Entry", Subp);
8973 ("incompatible implementation kind, overridden subprogram " &
8974 "is marked By_Protected_Procedure", Subp);
8977 end Check_Pragma_Implemented;
8979 --------------------------------
8980 -- Inherit_Pragma_Implemented --
8981 --------------------------------
8983 procedure Inherit_Pragma_Implemented
8985 Iface_Subp : Entity_Id)
8987 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
8988 Loc : constant Source_Ptr := Sloc (Subp);
8989 Impl_Prag : Node_Id;
8992 -- Since the implementation kind is stored as a representation item
8993 -- rather than a flag, create a pragma node.
8997 Chars => Name_Implemented,
8998 Pragma_Argument_Associations => New_List (
8999 Make_Pragma_Argument_Association (Loc,
9001 New_Reference_To (Subp, Loc)),
9003 Make_Pragma_Argument_Association (Loc,
9004 Expression => Make_Identifier (Loc, Iface_Kind))));
9006 -- The pragma doesn't need to be analyzed because it is internally
9007 -- build. It is safe to directly register it as a rep item since we
9008 -- are only interested in the characters of the implementation kind.
9010 Record_Rep_Item (Subp, Impl_Prag);
9011 end Inherit_Pragma_Implemented;
9013 -- Start of processing for Check_Abstract_Overriding
9016 Op_List := Primitive_Operations (T);
9018 -- Loop to check primitive operations
9020 Elmt := First_Elmt (Op_List);
9021 while Present (Elmt) loop
9022 Subp := Node (Elmt);
9023 Alias_Subp := Alias (Subp);
9025 -- Inherited subprograms are identified by the fact that they do not
9026 -- come from source, and the associated source location is the
9027 -- location of the first subtype of the derived type.
9029 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
9030 -- subprograms that "require overriding".
9032 -- Special exception, do not complain about failure to override the
9033 -- stream routines _Input and _Output, as well as the primitive
9034 -- operations used in dispatching selects since we always provide
9035 -- automatic overridings for these subprograms.
9037 -- Also ignore this rule for convention CIL since .NET libraries
9038 -- do bizarre things with interfaces???
9040 -- The partial view of T may have been a private extension, for
9041 -- which inherited functions dispatching on result are abstract.
9042 -- If the full view is a null extension, there is no need for
9043 -- overriding in Ada 2005, but wrappers need to be built for them
9044 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
9046 if Is_Null_Extension (T)
9047 and then Has_Controlling_Result (Subp)
9048 and then Ada_Version >= Ada_2005
9049 and then Present (Alias_Subp)
9050 and then not Comes_From_Source (Subp)
9051 and then not Is_Abstract_Subprogram (Alias_Subp)
9052 and then not Is_Access_Type (Etype (Subp))
9056 -- Ada 2005 (AI-251): Internal entities of interfaces need no
9057 -- processing because this check is done with the aliased
9060 elsif Present (Interface_Alias (Subp)) then
9063 elsif (Is_Abstract_Subprogram (Subp)
9064 or else Requires_Overriding (Subp)
9066 (Has_Controlling_Result (Subp)
9067 and then Present (Alias_Subp)
9068 and then not Comes_From_Source (Subp)
9069 and then Sloc (Subp) = Sloc (First_Subtype (T))))
9070 and then not Is_TSS (Subp, TSS_Stream_Input)
9071 and then not Is_TSS (Subp, TSS_Stream_Output)
9072 and then not Is_Abstract_Type (T)
9073 and then Convention (T) /= Convention_CIL
9074 and then not Is_Predefined_Interface_Primitive (Subp)
9076 -- Ada 2005 (AI-251): Do not consider hidden entities associated
9077 -- with abstract interface types because the check will be done
9078 -- with the aliased entity (otherwise we generate a duplicated
9081 and then not Present (Interface_Alias (Subp))
9083 if Present (Alias_Subp) then
9085 -- Only perform the check for a derived subprogram when the
9086 -- type has an explicit record extension. This avoids incorrect
9087 -- flagging of abstract subprograms for the case of a type
9088 -- without an extension that is derived from a formal type
9089 -- with a tagged actual (can occur within a private part).
9091 -- Ada 2005 (AI-391): In the case of an inherited function with
9092 -- a controlling result of the type, the rule does not apply if
9093 -- the type is a null extension (unless the parent function
9094 -- itself is abstract, in which case the function must still be
9095 -- be overridden). The expander will generate an overriding
9096 -- wrapper function calling the parent subprogram (see
9097 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
9099 Type_Def := Type_Definition (Parent (T));
9101 if Nkind (Type_Def) = N_Derived_Type_Definition
9102 and then Present (Record_Extension_Part (Type_Def))
9104 (Ada_Version < Ada_2005
9105 or else not Is_Null_Extension (T)
9106 or else Ekind (Subp) = E_Procedure
9107 or else not Has_Controlling_Result (Subp)
9108 or else Is_Abstract_Subprogram (Alias_Subp)
9109 or else Requires_Overriding (Subp)
9110 or else Is_Access_Type (Etype (Subp)))
9112 -- Avoid reporting error in case of abstract predefined
9113 -- primitive inherited from interface type because the
9114 -- body of internally generated predefined primitives
9115 -- of tagged types are generated later by Freeze_Type
9117 if Is_Interface (Root_Type (T))
9118 and then Is_Abstract_Subprogram (Subp)
9119 and then Is_Predefined_Dispatching_Operation (Subp)
9120 and then not Comes_From_Source (Ultimate_Alias (Subp))
9126 ("type must be declared abstract or & overridden",
9129 -- Traverse the whole chain of aliased subprograms to
9130 -- complete the error notification. This is especially
9131 -- useful for traceability of the chain of entities when
9132 -- the subprogram corresponds with an interface
9133 -- subprogram (which may be defined in another package).
9135 if Present (Alias_Subp) then
9141 while Present (Alias (E)) loop
9143 -- Avoid reporting redundant errors on entities
9144 -- inherited from interfaces
9146 if Sloc (E) /= Sloc (T) then
9147 Error_Msg_Sloc := Sloc (E);
9149 ("\& has been inherited #", T, Subp);
9155 Error_Msg_Sloc := Sloc (E);
9157 -- AI05-0068: report if there is an overriding
9158 -- non-abstract subprogram that is invisible.
9161 and then not Is_Abstract_Subprogram (E)
9164 ("\& subprogram# is not visible",
9169 ("\& has been inherited from subprogram #",
9176 -- Ada 2005 (AI-345): Protected or task type implementing
9177 -- abstract interfaces.
9179 elsif Is_Concurrent_Record_Type (T)
9180 and then Present (Interfaces (T))
9182 -- The controlling formal of Subp must be of mode "out",
9183 -- "in out" or an access-to-variable to be overridden.
9185 if Ekind (First_Formal (Subp)) = E_In_Parameter
9186 and then Ekind (Subp) /= E_Function
9188 if not Is_Predefined_Dispatching_Operation (Subp)
9189 and then Is_Protected_Type
9190 (Corresponding_Concurrent_Type (T))
9192 Error_Msg_PT (T, Subp);
9195 -- Some other kind of overriding failure
9199 ("interface subprogram & must be overridden",
9202 -- Examine primitive operations of synchronized type,
9203 -- to find homonyms that have the wrong profile.
9210 First_Entity (Corresponding_Concurrent_Type (T));
9211 while Present (Prim) loop
9212 if Chars (Prim) = Chars (Subp) then
9214 ("profile is not type conformant with "
9215 & "prefixed view profile of "
9216 & "inherited operation&", Prim, Subp);
9226 Error_Msg_Node_2 := T;
9228 ("abstract subprogram& not allowed for type&", Subp);
9230 -- Also post unconditional warning on the type (unconditional
9231 -- so that if there are more than one of these cases, we get
9232 -- them all, and not just the first one).
9234 Error_Msg_Node_2 := Subp;
9235 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
9239 -- Ada 2012 (AI05-0030): Perform some checks related to pragma
9242 -- Subp is an expander-generated procedure which maps an interface
9243 -- alias to a protected wrapper. The interface alias is flagged by
9244 -- pragma Implemented. Ensure that Subp is a procedure when the
9245 -- implementation kind is By_Protected_Procedure or an entry when
9248 if Ada_Version >= Ada_2012
9249 and then Is_Hidden (Subp)
9250 and then Present (Interface_Alias (Subp))
9251 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
9253 Check_Pragma_Implemented (Subp);
9256 -- Subp is an interface primitive which overrides another interface
9257 -- primitive marked with pragma Implemented.
9259 if Ada_Version >= Ada_2012
9260 and then Present (Overridden_Operation (Subp))
9261 and then Has_Rep_Pragma
9262 (Overridden_Operation (Subp), Name_Implemented)
9264 -- If the overriding routine is also marked by Implemented, check
9265 -- that the two implementation kinds are conforming.
9267 if Has_Rep_Pragma (Subp, Name_Implemented) then
9268 Check_Pragma_Implemented
9270 Iface_Subp => Overridden_Operation (Subp));
9272 -- Otherwise the overriding routine inherits the implementation
9273 -- kind from the overridden subprogram.
9276 Inherit_Pragma_Implemented
9278 Iface_Subp => Overridden_Operation (Subp));
9284 end Check_Abstract_Overriding;
9286 ------------------------------------------------
9287 -- Check_Access_Discriminant_Requires_Limited --
9288 ------------------------------------------------
9290 procedure Check_Access_Discriminant_Requires_Limited
9295 -- A discriminant_specification for an access discriminant shall appear
9296 -- only in the declaration for a task or protected type, or for a type
9297 -- with the reserved word 'limited' in its definition or in one of its
9298 -- ancestors (RM 3.7(10)).
9300 -- AI-0063: The proper condition is that type must be immutably limited,
9301 -- or else be a partial view.
9303 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
9304 if Is_Immutably_Limited_Type (Current_Scope)
9306 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
9307 and then Limited_Present (Parent (Current_Scope)))
9313 ("access discriminants allowed only for limited types", Loc);
9316 end Check_Access_Discriminant_Requires_Limited;
9318 -----------------------------------
9319 -- Check_Aliased_Component_Types --
9320 -----------------------------------
9322 procedure Check_Aliased_Component_Types (T : Entity_Id) is
9326 -- ??? Also need to check components of record extensions, but not
9327 -- components of protected types (which are always limited).
9329 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
9330 -- types to be unconstrained. This is safe because it is illegal to
9331 -- create access subtypes to such types with explicit discriminant
9334 if not Is_Limited_Type (T) then
9335 if Ekind (T) = E_Record_Type then
9336 C := First_Component (T);
9337 while Present (C) loop
9339 and then Has_Discriminants (Etype (C))
9340 and then not Is_Constrained (Etype (C))
9341 and then not In_Instance_Body
9342 and then Ada_Version < Ada_2005
9345 ("aliased component must be constrained (RM 3.6(11))",
9352 elsif Ekind (T) = E_Array_Type then
9353 if Has_Aliased_Components (T)
9354 and then Has_Discriminants (Component_Type (T))
9355 and then not Is_Constrained (Component_Type (T))
9356 and then not In_Instance_Body
9357 and then Ada_Version < Ada_2005
9360 ("aliased component type must be constrained (RM 3.6(11))",
9365 end Check_Aliased_Component_Types;
9367 ----------------------
9368 -- Check_Completion --
9369 ----------------------
9371 procedure Check_Completion (Body_Id : Node_Id := Empty) is
9374 procedure Post_Error;
9375 -- Post error message for lack of completion for entity E
9381 procedure Post_Error is
9383 procedure Missing_Body;
9384 -- Output missing body message
9390 procedure Missing_Body is
9392 -- Spec is in same unit, so we can post on spec
9394 if In_Same_Source_Unit (Body_Id, E) then
9395 Error_Msg_N ("missing body for &", E);
9397 -- Spec is in a separate unit, so we have to post on the body
9400 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
9404 -- Start of processing for Post_Error
9407 if not Comes_From_Source (E) then
9409 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
9410 -- It may be an anonymous protected type created for a
9411 -- single variable. Post error on variable, if present.
9417 Var := First_Entity (Current_Scope);
9418 while Present (Var) loop
9419 exit when Etype (Var) = E
9420 and then Comes_From_Source (Var);
9425 if Present (Var) then
9432 -- If a generated entity has no completion, then either previous
9433 -- semantic errors have disabled the expansion phase, or else we had
9434 -- missing subunits, or else we are compiling without expansion,
9435 -- or else something is very wrong.
9437 if not Comes_From_Source (E) then
9439 (Serious_Errors_Detected > 0
9440 or else Configurable_Run_Time_Violations > 0
9441 or else Subunits_Missing
9442 or else not Expander_Active);
9445 -- Here for source entity
9448 -- Here if no body to post the error message, so we post the error
9449 -- on the declaration that has no completion. This is not really
9450 -- the right place to post it, think about this later ???
9452 if No (Body_Id) then
9455 ("missing full declaration for }", Parent (E), E);
9457 Error_Msg_NE ("missing body for &", Parent (E), E);
9460 -- Package body has no completion for a declaration that appears
9461 -- in the corresponding spec. Post error on the body, with a
9462 -- reference to the non-completed declaration.
9465 Error_Msg_Sloc := Sloc (E);
9468 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
9470 elsif Is_Overloadable (E)
9471 and then Current_Entity_In_Scope (E) /= E
9473 -- It may be that the completion is mistyped and appears as
9474 -- a distinct overloading of the entity.
9477 Candidate : constant Entity_Id :=
9478 Current_Entity_In_Scope (E);
9479 Decl : constant Node_Id :=
9480 Unit_Declaration_Node (Candidate);
9483 if Is_Overloadable (Candidate)
9484 and then Ekind (Candidate) = Ekind (E)
9485 and then Nkind (Decl) = N_Subprogram_Body
9486 and then Acts_As_Spec (Decl)
9488 Check_Type_Conformant (Candidate, E);
9502 -- Start of processing for Check_Completion
9505 E := First_Entity (Current_Scope);
9506 while Present (E) loop
9507 if Is_Intrinsic_Subprogram (E) then
9510 -- The following situation requires special handling: a child unit
9511 -- that appears in the context clause of the body of its parent:
9513 -- procedure Parent.Child (...);
9515 -- with Parent.Child;
9516 -- package body Parent is
9518 -- Here Parent.Child appears as a local entity, but should not be
9519 -- flagged as requiring completion, because it is a compilation
9522 -- Ignore missing completion for a subprogram that does not come from
9523 -- source (including the _Call primitive operation of RAS types,
9524 -- which has to have the flag Comes_From_Source for other purposes):
9525 -- we assume that the expander will provide the missing completion.
9526 -- In case of previous errors, other expansion actions that provide
9527 -- bodies for null procedures with not be invoked, so inhibit message
9529 -- Note that E_Operator is not in the list that follows, because
9530 -- this kind is reserved for predefined operators, that are
9531 -- intrinsic and do not need completion.
9533 elsif Ekind (E) = E_Function
9534 or else Ekind (E) = E_Procedure
9535 or else Ekind (E) = E_Generic_Function
9536 or else Ekind (E) = E_Generic_Procedure
9538 if Has_Completion (E) then
9541 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
9544 elsif Is_Subprogram (E)
9545 and then (not Comes_From_Source (E)
9546 or else Chars (E) = Name_uCall)
9551 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
9555 elsif Nkind (Parent (E)) = N_Procedure_Specification
9556 and then Null_Present (Parent (E))
9557 and then Serious_Errors_Detected > 0
9565 elsif Is_Entry (E) then
9566 if not Has_Completion (E) and then
9567 (Ekind (Scope (E)) = E_Protected_Object
9568 or else Ekind (Scope (E)) = E_Protected_Type)
9573 elsif Is_Package_Or_Generic_Package (E) then
9574 if Unit_Requires_Body (E) then
9575 if not Has_Completion (E)
9576 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
9582 elsif not Is_Child_Unit (E) then
9583 May_Need_Implicit_Body (E);
9586 elsif Ekind (E) = E_Incomplete_Type
9587 and then No (Underlying_Type (E))
9591 elsif (Ekind (E) = E_Task_Type or else
9592 Ekind (E) = E_Protected_Type)
9593 and then not Has_Completion (E)
9597 -- A single task declared in the current scope is a constant, verify
9598 -- that the body of its anonymous type is in the same scope. If the
9599 -- task is defined elsewhere, this may be a renaming declaration for
9600 -- which no completion is needed.
9602 elsif Ekind (E) = E_Constant
9603 and then Ekind (Etype (E)) = E_Task_Type
9604 and then not Has_Completion (Etype (E))
9605 and then Scope (Etype (E)) = Current_Scope
9609 elsif Ekind (E) = E_Protected_Object
9610 and then not Has_Completion (Etype (E))
9614 elsif Ekind (E) = E_Record_Type then
9615 if Is_Tagged_Type (E) then
9616 Check_Abstract_Overriding (E);
9617 Check_Conventions (E);
9620 Check_Aliased_Component_Types (E);
9622 elsif Ekind (E) = E_Array_Type then
9623 Check_Aliased_Component_Types (E);
9629 end Check_Completion;
9631 ----------------------------
9632 -- Check_Delta_Expression --
9633 ----------------------------
9635 procedure Check_Delta_Expression (E : Node_Id) is
9637 if not (Is_Real_Type (Etype (E))) then
9638 Wrong_Type (E, Any_Real);
9640 elsif not Is_OK_Static_Expression (E) then
9641 Flag_Non_Static_Expr
9642 ("non-static expression used for delta value!", E);
9644 elsif not UR_Is_Positive (Expr_Value_R (E)) then
9645 Error_Msg_N ("delta expression must be positive", E);
9651 -- If any of above errors occurred, then replace the incorrect
9652 -- expression by the real 0.1, which should prevent further errors.
9655 Make_Real_Literal (Sloc (E), Ureal_Tenth));
9656 Analyze_And_Resolve (E, Standard_Float);
9657 end Check_Delta_Expression;
9659 -----------------------------
9660 -- Check_Digits_Expression --
9661 -----------------------------
9663 procedure Check_Digits_Expression (E : Node_Id) is
9665 if not (Is_Integer_Type (Etype (E))) then
9666 Wrong_Type (E, Any_Integer);
9668 elsif not Is_OK_Static_Expression (E) then
9669 Flag_Non_Static_Expr
9670 ("non-static expression used for digits value!", E);
9672 elsif Expr_Value (E) <= 0 then
9673 Error_Msg_N ("digits value must be greater than zero", E);
9679 -- If any of above errors occurred, then replace the incorrect
9680 -- expression by the integer 1, which should prevent further errors.
9682 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
9683 Analyze_And_Resolve (E, Standard_Integer);
9685 end Check_Digits_Expression;
9687 --------------------------
9688 -- Check_Initialization --
9689 --------------------------
9691 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
9693 if Is_Limited_Type (T)
9694 and then not In_Instance
9695 and then not In_Inlined_Body
9697 if not OK_For_Limited_Init (T, Exp) then
9699 -- In GNAT mode, this is just a warning, to allow it to be evilly
9700 -- turned off. Otherwise it is a real error.
9704 ("?cannot initialize entities of limited type!", Exp);
9706 elsif Ada_Version < Ada_2005 then
9708 ("cannot initialize entities of limited type", Exp);
9709 Explain_Limited_Type (T, Exp);
9712 -- Specialize error message according to kind of illegal
9713 -- initial expression.
9715 if Nkind (Exp) = N_Type_Conversion
9716 and then Nkind (Expression (Exp)) = N_Function_Call
9719 ("illegal context for call"
9720 & " to function with limited result", Exp);
9724 ("initialization of limited object requires aggregate "
9725 & "or function call", Exp);
9730 end Check_Initialization;
9732 ----------------------
9733 -- Check_Interfaces --
9734 ----------------------
9736 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
9737 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
9740 Iface_Def : Node_Id;
9741 Iface_Typ : Entity_Id;
9742 Parent_Node : Node_Id;
9744 Is_Task : Boolean := False;
9745 -- Set True if parent type or any progenitor is a task interface
9747 Is_Protected : Boolean := False;
9748 -- Set True if parent type or any progenitor is a protected interface
9750 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
9751 -- Check that a progenitor is compatible with declaration.
9752 -- Error is posted on Error_Node.
9758 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
9759 Iface_Id : constant Entity_Id :=
9760 Defining_Identifier (Parent (Iface_Def));
9764 if Nkind (N) = N_Private_Extension_Declaration then
9767 Type_Def := Type_Definition (N);
9770 if Is_Task_Interface (Iface_Id) then
9773 elsif Is_Protected_Interface (Iface_Id) then
9774 Is_Protected := True;
9777 if Is_Synchronized_Interface (Iface_Id) then
9779 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
9780 -- extension derived from a synchronized interface must explicitly
9781 -- be declared synchronized, because the full view will be a
9782 -- synchronized type.
9784 if Nkind (N) = N_Private_Extension_Declaration then
9785 if not Synchronized_Present (N) then
9787 ("private extension of& must be explicitly synchronized",
9791 -- However, by 3.9.4(16/2), a full type that is a record extension
9792 -- is never allowed to derive from a synchronized interface (note
9793 -- that interfaces must be excluded from this check, because those
9794 -- are represented by derived type definitions in some cases).
9796 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9797 and then not Interface_Present (Type_Definition (N))
9799 Error_Msg_N ("record extension cannot derive from synchronized"
9800 & " interface", Error_Node);
9804 -- Check that the characteristics of the progenitor are compatible
9805 -- with the explicit qualifier in the declaration.
9806 -- The check only applies to qualifiers that come from source.
9807 -- Limited_Present also appears in the declaration of corresponding
9808 -- records, and the check does not apply to them.
9810 if Limited_Present (Type_Def)
9812 Is_Concurrent_Record_Type (Defining_Identifier (N))
9814 if Is_Limited_Interface (Parent_Type)
9815 and then not Is_Limited_Interface (Iface_Id)
9818 ("progenitor& must be limited interface",
9819 Error_Node, Iface_Id);
9822 (Task_Present (Iface_Def)
9823 or else Protected_Present (Iface_Def)
9824 or else Synchronized_Present (Iface_Def))
9825 and then Nkind (N) /= N_Private_Extension_Declaration
9826 and then not Error_Posted (N)
9829 ("progenitor& must be limited interface",
9830 Error_Node, Iface_Id);
9833 -- Protected interfaces can only inherit from limited, synchronized
9834 -- or protected interfaces.
9836 elsif Nkind (N) = N_Full_Type_Declaration
9837 and then Protected_Present (Type_Def)
9839 if Limited_Present (Iface_Def)
9840 or else Synchronized_Present (Iface_Def)
9841 or else Protected_Present (Iface_Def)
9845 elsif Task_Present (Iface_Def) then
9846 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9847 & " from task interface", Error_Node);
9850 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9851 & " from non-limited interface", Error_Node);
9854 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
9855 -- limited and synchronized.
9857 elsif Synchronized_Present (Type_Def) then
9858 if Limited_Present (Iface_Def)
9859 or else Synchronized_Present (Iface_Def)
9863 elsif Protected_Present (Iface_Def)
9864 and then Nkind (N) /= N_Private_Extension_Declaration
9866 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9867 & " from protected interface", Error_Node);
9869 elsif Task_Present (Iface_Def)
9870 and then Nkind (N) /= N_Private_Extension_Declaration
9872 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9873 & " from task interface", Error_Node);
9875 elsif not Is_Limited_Interface (Iface_Id) then
9876 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9877 & " from non-limited interface", Error_Node);
9880 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
9881 -- synchronized or task interfaces.
9883 elsif Nkind (N) = N_Full_Type_Declaration
9884 and then Task_Present (Type_Def)
9886 if Limited_Present (Iface_Def)
9887 or else Synchronized_Present (Iface_Def)
9888 or else Task_Present (Iface_Def)
9892 elsif Protected_Present (Iface_Def) then
9893 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9894 & " protected interface", Error_Node);
9897 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9898 & " non-limited interface", Error_Node);
9903 -- Start of processing for Check_Interfaces
9906 if Is_Interface (Parent_Type) then
9907 if Is_Task_Interface (Parent_Type) then
9910 elsif Is_Protected_Interface (Parent_Type) then
9911 Is_Protected := True;
9915 if Nkind (N) = N_Private_Extension_Declaration then
9917 -- Check that progenitors are compatible with declaration
9919 Iface := First (Interface_List (Def));
9920 while Present (Iface) loop
9921 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9923 Parent_Node := Parent (Base_Type (Iface_Typ));
9924 Iface_Def := Type_Definition (Parent_Node);
9926 if not Is_Interface (Iface_Typ) then
9927 Diagnose_Interface (Iface, Iface_Typ);
9930 Check_Ifaces (Iface_Def, Iface);
9936 if Is_Task and Is_Protected then
9938 ("type cannot derive from task and protected interface", N);
9944 -- Full type declaration of derived type.
9945 -- Check compatibility with parent if it is interface type
9947 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9948 and then Is_Interface (Parent_Type)
9950 Parent_Node := Parent (Parent_Type);
9952 -- More detailed checks for interface varieties
9955 (Iface_Def => Type_Definition (Parent_Node),
9956 Error_Node => Subtype_Indication (Type_Definition (N)));
9959 Iface := First (Interface_List (Def));
9960 while Present (Iface) loop
9961 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9963 Parent_Node := Parent (Base_Type (Iface_Typ));
9964 Iface_Def := Type_Definition (Parent_Node);
9966 if not Is_Interface (Iface_Typ) then
9967 Diagnose_Interface (Iface, Iface_Typ);
9970 -- "The declaration of a specific descendant of an interface
9971 -- type freezes the interface type" RM 13.14
9973 Freeze_Before (N, Iface_Typ);
9974 Check_Ifaces (Iface_Def, Error_Node => Iface);
9980 if Is_Task and Is_Protected then
9982 ("type cannot derive from task and protected interface", N);
9984 end Check_Interfaces;
9986 ------------------------------------
9987 -- Check_Or_Process_Discriminants --
9988 ------------------------------------
9990 -- If an incomplete or private type declaration was already given for the
9991 -- type, the discriminants may have already been processed if they were
9992 -- present on the incomplete declaration. In this case a full conformance
9993 -- check has been performed in Find_Type_Name, and we then recheck here
9994 -- some properties that can't be checked on the partial view alone.
9995 -- Otherwise we call Process_Discriminants.
9997 procedure Check_Or_Process_Discriminants
10000 Prev : Entity_Id := Empty)
10003 if Has_Discriminants (T) then
10005 -- Discriminants are already set on T if they were already present
10006 -- on the partial view. Make them visible to component declarations.
10010 -- Discriminant on T (full view) referencing expr on partial view
10012 Prev_D : Entity_Id;
10013 -- Entity of corresponding discriminant on partial view
10016 -- Discriminant specification for full view, expression is the
10017 -- syntactic copy on full view (which has been checked for
10018 -- conformance with partial view), only used here to post error
10022 D := First_Discriminant (T);
10023 New_D := First (Discriminant_Specifications (N));
10024 while Present (D) loop
10025 Prev_D := Current_Entity (D);
10026 Set_Current_Entity (D);
10027 Set_Is_Immediately_Visible (D);
10028 Set_Homonym (D, Prev_D);
10030 -- Handle the case where there is an untagged partial view and
10031 -- the full view is tagged: must disallow discriminants with
10032 -- defaults, unless compiling for Ada 2012, which allows a
10033 -- limited tagged type to have defaulted discriminants (see
10034 -- AI05-0214). However, suppress the error here if it was
10035 -- already reported on the default expression of the partial
10038 if Is_Tagged_Type (T)
10039 and then Present (Expression (Parent (D)))
10040 and then (not Is_Limited_Type (Current_Scope)
10041 or else Ada_Version < Ada_2012)
10042 and then not Error_Posted (Expression (Parent (D)))
10044 if Ada_Version >= Ada_2012 then
10046 ("discriminants of nonlimited tagged type cannot have"
10048 Expression (New_D));
10051 ("discriminants of tagged type cannot have defaults",
10052 Expression (New_D));
10056 -- Ada 2005 (AI-230): Access discriminant allowed in
10057 -- non-limited record types.
10059 if Ada_Version < Ada_2005 then
10061 -- This restriction gets applied to the full type here. It
10062 -- has already been applied earlier to the partial view.
10064 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
10067 Next_Discriminant (D);
10072 elsif Present (Discriminant_Specifications (N)) then
10073 Process_Discriminants (N, Prev);
10075 end Check_Or_Process_Discriminants;
10077 ----------------------
10078 -- Check_Real_Bound --
10079 ----------------------
10081 procedure Check_Real_Bound (Bound : Node_Id) is
10083 if not Is_Real_Type (Etype (Bound)) then
10085 ("bound in real type definition must be of real type", Bound);
10087 elsif not Is_OK_Static_Expression (Bound) then
10088 Flag_Non_Static_Expr
10089 ("non-static expression used for real type bound!", Bound);
10096 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
10098 Resolve (Bound, Standard_Float);
10099 end Check_Real_Bound;
10101 ------------------------------
10102 -- Complete_Private_Subtype --
10103 ------------------------------
10105 procedure Complete_Private_Subtype
10108 Full_Base : Entity_Id;
10109 Related_Nod : Node_Id)
10111 Save_Next_Entity : Entity_Id;
10112 Save_Homonym : Entity_Id;
10115 -- Set semantic attributes for (implicit) private subtype completion.
10116 -- If the full type has no discriminants, then it is a copy of the full
10117 -- view of the base. Otherwise, it is a subtype of the base with a
10118 -- possible discriminant constraint. Save and restore the original
10119 -- Next_Entity field of full to ensure that the calls to Copy_Node
10120 -- do not corrupt the entity chain.
10122 -- Note that the type of the full view is the same entity as the type of
10123 -- the partial view. In this fashion, the subtype has access to the
10124 -- correct view of the parent.
10126 Save_Next_Entity := Next_Entity (Full);
10127 Save_Homonym := Homonym (Priv);
10129 case Ekind (Full_Base) is
10130 when E_Record_Type |
10136 Copy_Node (Priv, Full);
10138 Set_Has_Discriminants (Full, Has_Discriminants (Full_Base));
10139 Set_First_Entity (Full, First_Entity (Full_Base));
10140 Set_Last_Entity (Full, Last_Entity (Full_Base));
10143 Copy_Node (Full_Base, Full);
10144 Set_Chars (Full, Chars (Priv));
10145 Conditional_Delay (Full, Priv);
10146 Set_Sloc (Full, Sloc (Priv));
10149 Set_Next_Entity (Full, Save_Next_Entity);
10150 Set_Homonym (Full, Save_Homonym);
10151 Set_Associated_Node_For_Itype (Full, Related_Nod);
10153 -- Set common attributes for all subtypes: kind, convention, etc.
10155 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
10156 Set_Convention (Full, Convention (Full_Base));
10158 -- The Etype of the full view is inconsistent. Gigi needs to see the
10159 -- structural full view, which is what the current scheme gives:
10160 -- the Etype of the full view is the etype of the full base. However,
10161 -- if the full base is a derived type, the full view then looks like
10162 -- a subtype of the parent, not a subtype of the full base. If instead
10165 -- Set_Etype (Full, Full_Base);
10167 -- then we get inconsistencies in the front-end (confusion between
10168 -- views). Several outstanding bugs are related to this ???
10170 Set_Is_First_Subtype (Full, False);
10171 Set_Scope (Full, Scope (Priv));
10172 Set_Size_Info (Full, Full_Base);
10173 Set_RM_Size (Full, RM_Size (Full_Base));
10174 Set_Is_Itype (Full);
10176 -- A subtype of a private-type-without-discriminants, whose full-view
10177 -- has discriminants with default expressions, is not constrained!
10179 if not Has_Discriminants (Priv) then
10180 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
10182 if Has_Discriminants (Full_Base) then
10183 Set_Discriminant_Constraint
10184 (Full, Discriminant_Constraint (Full_Base));
10186 -- The partial view may have been indefinite, the full view
10189 Set_Has_Unknown_Discriminants
10190 (Full, Has_Unknown_Discriminants (Full_Base));
10194 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
10195 Set_Depends_On_Private (Full, Has_Private_Component (Full));
10197 -- Freeze the private subtype entity if its parent is delayed, and not
10198 -- already frozen. We skip this processing if the type is an anonymous
10199 -- subtype of a record component, or is the corresponding record of a
10200 -- protected type, since ???
10202 if not Is_Type (Scope (Full)) then
10203 Set_Has_Delayed_Freeze (Full,
10204 Has_Delayed_Freeze (Full_Base)
10205 and then (not Is_Frozen (Full_Base)));
10208 Set_Freeze_Node (Full, Empty);
10209 Set_Is_Frozen (Full, False);
10210 Set_Full_View (Priv, Full);
10212 if Has_Discriminants (Full) then
10213 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
10214 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
10216 if Has_Unknown_Discriminants (Full) then
10217 Set_Discriminant_Constraint (Full, No_Elist);
10221 if Ekind (Full_Base) = E_Record_Type
10222 and then Has_Discriminants (Full_Base)
10223 and then Has_Discriminants (Priv) -- might not, if errors
10224 and then not Has_Unknown_Discriminants (Priv)
10225 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
10227 Create_Constrained_Components
10228 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
10230 -- If the full base is itself derived from private, build a congruent
10231 -- subtype of its underlying type, for use by the back end. For a
10232 -- constrained record component, the declaration cannot be placed on
10233 -- the component list, but it must nevertheless be built an analyzed, to
10234 -- supply enough information for Gigi to compute the size of component.
10236 elsif Ekind (Full_Base) in Private_Kind
10237 and then Is_Derived_Type (Full_Base)
10238 and then Has_Discriminants (Full_Base)
10239 and then (Ekind (Current_Scope) /= E_Record_Subtype)
10241 if not Is_Itype (Priv)
10243 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
10245 Build_Underlying_Full_View
10246 (Parent (Priv), Full, Etype (Full_Base));
10248 elsif Nkind (Related_Nod) = N_Component_Declaration then
10249 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
10252 elsif Is_Record_Type (Full_Base) then
10254 -- Show Full is simply a renaming of Full_Base
10256 Set_Cloned_Subtype (Full, Full_Base);
10259 -- It is unsafe to share to bounds of a scalar type, because the Itype
10260 -- is elaborated on demand, and if a bound is non-static then different
10261 -- orders of elaboration in different units will lead to different
10262 -- external symbols.
10264 if Is_Scalar_Type (Full_Base) then
10265 Set_Scalar_Range (Full,
10266 Make_Range (Sloc (Related_Nod),
10268 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
10270 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
10272 -- This completion inherits the bounds of the full parent, but if
10273 -- the parent is an unconstrained floating point type, so is the
10276 if Is_Floating_Point_Type (Full_Base) then
10277 Set_Includes_Infinities
10278 (Scalar_Range (Full), Has_Infinities (Full_Base));
10282 -- ??? It seems that a lot of fields are missing that should be copied
10283 -- from Full_Base to Full. Here are some that are introduced in a
10284 -- non-disruptive way but a cleanup is necessary.
10286 if Is_Tagged_Type (Full_Base) then
10287 Set_Is_Tagged_Type (Full);
10288 Set_Direct_Primitive_Operations (Full,
10289 Direct_Primitive_Operations (Full_Base));
10291 -- Inherit class_wide type of full_base in case the partial view was
10292 -- not tagged. Otherwise it has already been created when the private
10293 -- subtype was analyzed.
10295 if No (Class_Wide_Type (Full)) then
10296 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
10299 -- If this is a subtype of a protected or task type, constrain its
10300 -- corresponding record, unless this is a subtype without constraints,
10301 -- i.e. a simple renaming as with an actual subtype in an instance.
10303 elsif Is_Concurrent_Type (Full_Base) then
10304 if Has_Discriminants (Full)
10305 and then Present (Corresponding_Record_Type (Full_Base))
10307 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
10309 Set_Corresponding_Record_Type (Full,
10310 Constrain_Corresponding_Record
10311 (Full, Corresponding_Record_Type (Full_Base),
10312 Related_Nod, Full_Base));
10315 Set_Corresponding_Record_Type (Full,
10316 Corresponding_Record_Type (Full_Base));
10320 -- Link rep item chain, and also setting of Has_Predicates from private
10321 -- subtype to full subtype, since we will need these on the full subtype
10322 -- to create the predicate function. Note that the full subtype may
10323 -- already have rep items, inherited from the full view of the base
10324 -- type, so we must be sure not to overwrite these entries.
10329 Next_Item : Node_Id;
10332 Item := First_Rep_Item (Full);
10334 -- If no existing rep items on full type, we can just link directly
10335 -- to the list of items on the private type.
10338 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
10340 -- Otherwise, search to the end of items currently linked to the full
10341 -- subtype and append the private items to the end. However, if Priv
10342 -- and Full already have the same list of rep items, then the append
10343 -- is not done, as that would create a circularity.
10345 elsif Item /= First_Rep_Item (Priv) then
10349 Next_Item := Next_Rep_Item (Item);
10350 exit when No (Next_Item);
10353 -- If the private view has aspect specifications, the full view
10354 -- inherits them. Since these aspects may already have been
10355 -- attached to the full view during derivation, do not append
10356 -- them if already present.
10358 if Item = First_Rep_Item (Priv) then
10364 -- And link the private type items at the end of the chain
10367 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
10372 -- Make sure Has_Predicates is set on full type if it is set on the
10373 -- private type. Note that it may already be set on the full type and
10374 -- if so, we don't want to unset it.
10376 if Has_Predicates (Priv) then
10377 Set_Has_Predicates (Full);
10379 end Complete_Private_Subtype;
10381 ----------------------------
10382 -- Constant_Redeclaration --
10383 ----------------------------
10385 procedure Constant_Redeclaration
10390 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
10391 Obj_Def : constant Node_Id := Object_Definition (N);
10394 procedure Check_Possible_Deferred_Completion
10395 (Prev_Id : Entity_Id;
10396 Prev_Obj_Def : Node_Id;
10397 Curr_Obj_Def : Node_Id);
10398 -- Determine whether the two object definitions describe the partial
10399 -- and the full view of a constrained deferred constant. Generate
10400 -- a subtype for the full view and verify that it statically matches
10401 -- the subtype of the partial view.
10403 procedure Check_Recursive_Declaration (Typ : Entity_Id);
10404 -- If deferred constant is an access type initialized with an allocator,
10405 -- check whether there is an illegal recursion in the definition,
10406 -- through a default value of some record subcomponent. This is normally
10407 -- detected when generating init procs, but requires this additional
10408 -- mechanism when expansion is disabled.
10410 ----------------------------------------
10411 -- Check_Possible_Deferred_Completion --
10412 ----------------------------------------
10414 procedure Check_Possible_Deferred_Completion
10415 (Prev_Id : Entity_Id;
10416 Prev_Obj_Def : Node_Id;
10417 Curr_Obj_Def : Node_Id)
10420 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
10421 and then Present (Constraint (Prev_Obj_Def))
10422 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
10423 and then Present (Constraint (Curr_Obj_Def))
10426 Loc : constant Source_Ptr := Sloc (N);
10427 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
10428 Decl : constant Node_Id :=
10429 Make_Subtype_Declaration (Loc,
10430 Defining_Identifier => Def_Id,
10431 Subtype_Indication =>
10432 Relocate_Node (Curr_Obj_Def));
10435 Insert_Before_And_Analyze (N, Decl);
10436 Set_Etype (Id, Def_Id);
10438 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
10439 Error_Msg_Sloc := Sloc (Prev_Id);
10440 Error_Msg_N ("subtype does not statically match deferred " &
10441 "declaration#", N);
10445 end Check_Possible_Deferred_Completion;
10447 ---------------------------------
10448 -- Check_Recursive_Declaration --
10449 ---------------------------------
10451 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
10455 if Is_Record_Type (Typ) then
10456 Comp := First_Component (Typ);
10457 while Present (Comp) loop
10458 if Comes_From_Source (Comp) then
10459 if Present (Expression (Parent (Comp)))
10460 and then Is_Entity_Name (Expression (Parent (Comp)))
10461 and then Entity (Expression (Parent (Comp))) = Prev
10463 Error_Msg_Sloc := Sloc (Parent (Comp));
10465 ("illegal circularity with declaration for&#",
10469 elsif Is_Record_Type (Etype (Comp)) then
10470 Check_Recursive_Declaration (Etype (Comp));
10474 Next_Component (Comp);
10477 end Check_Recursive_Declaration;
10479 -- Start of processing for Constant_Redeclaration
10482 if Nkind (Parent (Prev)) = N_Object_Declaration then
10483 if Nkind (Object_Definition
10484 (Parent (Prev))) = N_Subtype_Indication
10486 -- Find type of new declaration. The constraints of the two
10487 -- views must match statically, but there is no point in
10488 -- creating an itype for the full view.
10490 if Nkind (Obj_Def) = N_Subtype_Indication then
10491 Find_Type (Subtype_Mark (Obj_Def));
10492 New_T := Entity (Subtype_Mark (Obj_Def));
10495 Find_Type (Obj_Def);
10496 New_T := Entity (Obj_Def);
10502 -- The full view may impose a constraint, even if the partial
10503 -- view does not, so construct the subtype.
10505 New_T := Find_Type_Of_Object (Obj_Def, N);
10510 -- Current declaration is illegal, diagnosed below in Enter_Name
10516 -- If previous full declaration or a renaming declaration exists, or if
10517 -- a homograph is present, let Enter_Name handle it, either with an
10518 -- error or with the removal of an overridden implicit subprogram.
10520 if Ekind (Prev) /= E_Constant
10521 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
10522 or else Present (Expression (Parent (Prev)))
10523 or else Present (Full_View (Prev))
10527 -- Verify that types of both declarations match, or else that both types
10528 -- are anonymous access types whose designated subtypes statically match
10529 -- (as allowed in Ada 2005 by AI-385).
10531 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
10533 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
10534 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
10535 or else Is_Access_Constant (Etype (New_T)) /=
10536 Is_Access_Constant (Etype (Prev))
10537 or else Can_Never_Be_Null (Etype (New_T)) /=
10538 Can_Never_Be_Null (Etype (Prev))
10539 or else Null_Exclusion_Present (Parent (Prev)) /=
10540 Null_Exclusion_Present (Parent (Id))
10541 or else not Subtypes_Statically_Match
10542 (Designated_Type (Etype (Prev)),
10543 Designated_Type (Etype (New_T))))
10545 Error_Msg_Sloc := Sloc (Prev);
10546 Error_Msg_N ("type does not match declaration#", N);
10547 Set_Full_View (Prev, Id);
10548 Set_Etype (Id, Any_Type);
10551 Null_Exclusion_Present (Parent (Prev))
10552 and then not Null_Exclusion_Present (N)
10554 Error_Msg_Sloc := Sloc (Prev);
10555 Error_Msg_N ("null-exclusion does not match declaration#", N);
10556 Set_Full_View (Prev, Id);
10557 Set_Etype (Id, Any_Type);
10559 -- If so, process the full constant declaration
10562 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
10563 -- the deferred declaration is constrained, then the subtype defined
10564 -- by the subtype_indication in the full declaration shall match it
10567 Check_Possible_Deferred_Completion
10569 Prev_Obj_Def => Object_Definition (Parent (Prev)),
10570 Curr_Obj_Def => Obj_Def);
10572 Set_Full_View (Prev, Id);
10573 Set_Is_Public (Id, Is_Public (Prev));
10574 Set_Is_Internal (Id);
10575 Append_Entity (Id, Current_Scope);
10577 -- Check ALIASED present if present before (RM 7.4(7))
10579 if Is_Aliased (Prev)
10580 and then not Aliased_Present (N)
10582 Error_Msg_Sloc := Sloc (Prev);
10583 Error_Msg_N ("ALIASED required (see declaration#)", N);
10586 -- Check that placement is in private part and that the incomplete
10587 -- declaration appeared in the visible part.
10589 if Ekind (Current_Scope) = E_Package
10590 and then not In_Private_Part (Current_Scope)
10592 Error_Msg_Sloc := Sloc (Prev);
10594 ("full constant for declaration#"
10595 & " must be in private part", N);
10597 elsif Ekind (Current_Scope) = E_Package
10599 List_Containing (Parent (Prev)) /=
10600 Visible_Declarations
10601 (Specification (Unit_Declaration_Node (Current_Scope)))
10604 ("deferred constant must be declared in visible part",
10608 if Is_Access_Type (T)
10609 and then Nkind (Expression (N)) = N_Allocator
10611 Check_Recursive_Declaration (Designated_Type (T));
10614 end Constant_Redeclaration;
10616 ----------------------
10617 -- Constrain_Access --
10618 ----------------------
10620 procedure Constrain_Access
10621 (Def_Id : in out Entity_Id;
10623 Related_Nod : Node_Id)
10625 T : constant Entity_Id := Entity (Subtype_Mark (S));
10626 Desig_Type : constant Entity_Id := Designated_Type (T);
10627 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
10628 Constraint_OK : Boolean := True;
10630 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean;
10631 -- Simple predicate to test for defaulted discriminants
10632 -- Shouldn't this be in sem_util???
10634 ---------------------------------
10635 -- Has_Defaulted_Discriminants --
10636 ---------------------------------
10638 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean is
10640 return Has_Discriminants (Typ)
10641 and then Present (First_Discriminant (Typ))
10643 (Discriminant_Default_Value (First_Discriminant (Typ)));
10644 end Has_Defaulted_Discriminants;
10646 -- Start of processing for Constrain_Access
10649 if Is_Array_Type (Desig_Type) then
10650 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
10652 elsif (Is_Record_Type (Desig_Type)
10653 or else Is_Incomplete_Or_Private_Type (Desig_Type))
10654 and then not Is_Constrained (Desig_Type)
10656 -- ??? The following code is a temporary kludge to ignore a
10657 -- discriminant constraint on access type if it is constraining
10658 -- the current record. Avoid creating the implicit subtype of the
10659 -- record we are currently compiling since right now, we cannot
10660 -- handle these. For now, just return the access type itself.
10662 if Desig_Type = Current_Scope
10663 and then No (Def_Id)
10665 Set_Ekind (Desig_Subtype, E_Record_Subtype);
10666 Def_Id := Entity (Subtype_Mark (S));
10668 -- This call added to ensure that the constraint is analyzed
10669 -- (needed for a B test). Note that we still return early from
10670 -- this procedure to avoid recursive processing. ???
10672 Constrain_Discriminated_Type
10673 (Desig_Subtype, S, Related_Nod, For_Access => True);
10677 if (Ekind (T) = E_General_Access_Type
10678 or else Ada_Version >= Ada_2005)
10679 and then Has_Private_Declaration (Desig_Type)
10680 and then In_Open_Scopes (Scope (Desig_Type))
10681 and then Has_Discriminants (Desig_Type)
10683 -- Enforce rule that the constraint is illegal if there is
10684 -- an unconstrained view of the designated type. This means
10685 -- that the partial view (either a private type declaration or
10686 -- a derivation from a private type) has no discriminants.
10687 -- (Defect Report 8652/0008, Technical Corrigendum 1, checked
10688 -- by ACATS B371001).
10690 -- Rule updated for Ada 2005: the private type is said to have
10691 -- a constrained partial view, given that objects of the type
10692 -- can be declared. Furthermore, the rule applies to all access
10693 -- types, unlike the rule concerning default discriminants.
10696 Pack : constant Node_Id :=
10697 Unit_Declaration_Node (Scope (Desig_Type));
10702 if Nkind (Pack) = N_Package_Declaration then
10703 Decls := Visible_Declarations (Specification (Pack));
10704 Decl := First (Decls);
10705 while Present (Decl) loop
10706 if (Nkind (Decl) = N_Private_Type_Declaration
10708 Chars (Defining_Identifier (Decl)) =
10709 Chars (Desig_Type))
10712 (Nkind (Decl) = N_Full_Type_Declaration
10714 Chars (Defining_Identifier (Decl)) =
10716 and then Is_Derived_Type (Desig_Type)
10718 Has_Private_Declaration (Etype (Desig_Type)))
10720 if No (Discriminant_Specifications (Decl)) then
10722 ("cannot constrain general access type if " &
10723 "designated type has constrained partial view",
10736 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
10737 For_Access => True);
10739 elsif (Is_Task_Type (Desig_Type)
10740 or else Is_Protected_Type (Desig_Type))
10741 and then not Is_Constrained (Desig_Type)
10743 Constrain_Concurrent
10744 (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
10747 Error_Msg_N ("invalid constraint on access type", S);
10748 Desig_Subtype := Desig_Type; -- Ignore invalid constraint.
10749 Constraint_OK := False;
10752 if No (Def_Id) then
10753 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
10755 Set_Ekind (Def_Id, E_Access_Subtype);
10758 if Constraint_OK then
10759 Set_Etype (Def_Id, Base_Type (T));
10761 if Is_Private_Type (Desig_Type) then
10762 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
10765 Set_Etype (Def_Id, Any_Type);
10768 Set_Size_Info (Def_Id, T);
10769 Set_Is_Constrained (Def_Id, Constraint_OK);
10770 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
10771 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10772 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
10774 Conditional_Delay (Def_Id, T);
10776 -- AI-363 : Subtypes of general access types whose designated types have
10777 -- default discriminants are disallowed. In instances, the rule has to
10778 -- be checked against the actual, of which T is the subtype. In a
10779 -- generic body, the rule is checked assuming that the actual type has
10780 -- defaulted discriminants.
10782 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
10783 if Ekind (Base_Type (T)) = E_General_Access_Type
10784 and then Has_Defaulted_Discriminants (Desig_Type)
10786 if Ada_Version < Ada_2005 then
10788 ("access subtype of general access type would not " &
10789 "be allowed in Ada 2005?", S);
10792 ("access subtype of general access type not allowed", S);
10795 Error_Msg_N ("\discriminants have defaults", S);
10797 elsif Is_Access_Type (T)
10798 and then Is_Generic_Type (Desig_Type)
10799 and then Has_Discriminants (Desig_Type)
10800 and then In_Package_Body (Current_Scope)
10802 if Ada_Version < Ada_2005 then
10804 ("access subtype would not be allowed in generic body " &
10805 "in Ada 2005?", S);
10808 ("access subtype not allowed in generic body", S);
10812 ("\designated type is a discriminated formal", S);
10815 end Constrain_Access;
10817 ---------------------
10818 -- Constrain_Array --
10819 ---------------------
10821 procedure Constrain_Array
10822 (Def_Id : in out Entity_Id;
10824 Related_Nod : Node_Id;
10825 Related_Id : Entity_Id;
10826 Suffix : Character)
10828 C : constant Node_Id := Constraint (SI);
10829 Number_Of_Constraints : Nat := 0;
10832 Constraint_OK : Boolean := True;
10835 T := Entity (Subtype_Mark (SI));
10837 if Ekind (T) in Access_Kind then
10838 T := Designated_Type (T);
10841 -- If an index constraint follows a subtype mark in a subtype indication
10842 -- then the type or subtype denoted by the subtype mark must not already
10843 -- impose an index constraint. The subtype mark must denote either an
10844 -- unconstrained array type or an access type whose designated type
10845 -- is such an array type... (RM 3.6.1)
10847 if Is_Constrained (T) then
10848 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
10849 Constraint_OK := False;
10852 S := First (Constraints (C));
10853 while Present (S) loop
10854 Number_Of_Constraints := Number_Of_Constraints + 1;
10858 -- In either case, the index constraint must provide a discrete
10859 -- range for each index of the array type and the type of each
10860 -- discrete range must be the same as that of the corresponding
10861 -- index. (RM 3.6.1)
10863 if Number_Of_Constraints /= Number_Dimensions (T) then
10864 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
10865 Constraint_OK := False;
10868 S := First (Constraints (C));
10869 Index := First_Index (T);
10872 -- Apply constraints to each index type
10874 for J in 1 .. Number_Of_Constraints loop
10875 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
10883 if No (Def_Id) then
10885 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
10886 Set_Parent (Def_Id, Related_Nod);
10889 Set_Ekind (Def_Id, E_Array_Subtype);
10892 Set_Size_Info (Def_Id, (T));
10893 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10894 Set_Etype (Def_Id, Base_Type (T));
10896 if Constraint_OK then
10897 Set_First_Index (Def_Id, First (Constraints (C)));
10899 Set_First_Index (Def_Id, First_Index (T));
10902 Set_Is_Constrained (Def_Id, True);
10903 Set_Is_Aliased (Def_Id, Is_Aliased (T));
10904 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10906 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
10907 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
10909 -- A subtype does not inherit the packed_array_type of is parent. We
10910 -- need to initialize the attribute because if Def_Id is previously
10911 -- analyzed through a limited_with clause, it will have the attributes
10912 -- of an incomplete type, one of which is an Elist that overlaps the
10913 -- Packed_Array_Type field.
10915 Set_Packed_Array_Type (Def_Id, Empty);
10917 -- Build a freeze node if parent still needs one. Also make sure that
10918 -- the Depends_On_Private status is set because the subtype will need
10919 -- reprocessing at the time the base type does, and also we must set a
10920 -- conditional delay.
10922 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
10923 Conditional_Delay (Def_Id, T);
10924 end Constrain_Array;
10926 ------------------------------
10927 -- Constrain_Component_Type --
10928 ------------------------------
10930 function Constrain_Component_Type
10932 Constrained_Typ : Entity_Id;
10933 Related_Node : Node_Id;
10935 Constraints : Elist_Id) return Entity_Id
10937 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
10938 Compon_Type : constant Entity_Id := Etype (Comp);
10940 function Build_Constrained_Array_Type
10941 (Old_Type : Entity_Id) return Entity_Id;
10942 -- If Old_Type is an array type, one of whose indexes is constrained
10943 -- by a discriminant, build an Itype whose constraint replaces the
10944 -- discriminant with its value in the constraint.
10946 function Build_Constrained_Discriminated_Type
10947 (Old_Type : Entity_Id) return Entity_Id;
10948 -- Ditto for record components
10950 function Build_Constrained_Access_Type
10951 (Old_Type : Entity_Id) return Entity_Id;
10952 -- Ditto for access types. Makes use of previous two functions, to
10953 -- constrain designated type.
10955 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
10956 -- T is an array or discriminated type, C is a list of constraints
10957 -- that apply to T. This routine builds the constrained subtype.
10959 function Is_Discriminant (Expr : Node_Id) return Boolean;
10960 -- Returns True if Expr is a discriminant
10962 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
10963 -- Find the value of discriminant Discrim in Constraint
10965 -----------------------------------
10966 -- Build_Constrained_Access_Type --
10967 -----------------------------------
10969 function Build_Constrained_Access_Type
10970 (Old_Type : Entity_Id) return Entity_Id
10972 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
10974 Desig_Subtype : Entity_Id;
10978 -- if the original access type was not embedded in the enclosing
10979 -- type definition, there is no need to produce a new access
10980 -- subtype. In fact every access type with an explicit constraint
10981 -- generates an itype whose scope is the enclosing record.
10983 if not Is_Type (Scope (Old_Type)) then
10986 elsif Is_Array_Type (Desig_Type) then
10987 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
10989 elsif Has_Discriminants (Desig_Type) then
10991 -- This may be an access type to an enclosing record type for
10992 -- which we are constructing the constrained components. Return
10993 -- the enclosing record subtype. This is not always correct,
10994 -- but avoids infinite recursion. ???
10996 Desig_Subtype := Any_Type;
10998 for J in reverse 0 .. Scope_Stack.Last loop
10999 Scop := Scope_Stack.Table (J).Entity;
11002 and then Base_Type (Scop) = Base_Type (Desig_Type)
11004 Desig_Subtype := Scop;
11007 exit when not Is_Type (Scop);
11010 if Desig_Subtype = Any_Type then
11012 Build_Constrained_Discriminated_Type (Desig_Type);
11019 if Desig_Subtype /= Desig_Type then
11021 -- The Related_Node better be here or else we won't be able
11022 -- to attach new itypes to a node in the tree.
11024 pragma Assert (Present (Related_Node));
11026 Itype := Create_Itype (E_Access_Subtype, Related_Node);
11028 Set_Etype (Itype, Base_Type (Old_Type));
11029 Set_Size_Info (Itype, (Old_Type));
11030 Set_Directly_Designated_Type (Itype, Desig_Subtype);
11031 Set_Depends_On_Private (Itype, Has_Private_Component
11033 Set_Is_Access_Constant (Itype, Is_Access_Constant
11036 -- The new itype needs freezing when it depends on a not frozen
11037 -- type and the enclosing subtype needs freezing.
11039 if Has_Delayed_Freeze (Constrained_Typ)
11040 and then not Is_Frozen (Constrained_Typ)
11042 Conditional_Delay (Itype, Base_Type (Old_Type));
11050 end Build_Constrained_Access_Type;
11052 ----------------------------------
11053 -- Build_Constrained_Array_Type --
11054 ----------------------------------
11056 function Build_Constrained_Array_Type
11057 (Old_Type : Entity_Id) return Entity_Id
11061 Old_Index : Node_Id;
11062 Range_Node : Node_Id;
11063 Constr_List : List_Id;
11065 Need_To_Create_Itype : Boolean := False;
11068 Old_Index := First_Index (Old_Type);
11069 while Present (Old_Index) loop
11070 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
11072 if Is_Discriminant (Lo_Expr)
11073 or else Is_Discriminant (Hi_Expr)
11075 Need_To_Create_Itype := True;
11078 Next_Index (Old_Index);
11081 if Need_To_Create_Itype then
11082 Constr_List := New_List;
11084 Old_Index := First_Index (Old_Type);
11085 while Present (Old_Index) loop
11086 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
11088 if Is_Discriminant (Lo_Expr) then
11089 Lo_Expr := Get_Discr_Value (Lo_Expr);
11092 if Is_Discriminant (Hi_Expr) then
11093 Hi_Expr := Get_Discr_Value (Hi_Expr);
11098 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
11100 Append (Range_Node, To => Constr_List);
11102 Next_Index (Old_Index);
11105 return Build_Subtype (Old_Type, Constr_List);
11110 end Build_Constrained_Array_Type;
11112 ------------------------------------------
11113 -- Build_Constrained_Discriminated_Type --
11114 ------------------------------------------
11116 function Build_Constrained_Discriminated_Type
11117 (Old_Type : Entity_Id) return Entity_Id
11120 Constr_List : List_Id;
11121 Old_Constraint : Elmt_Id;
11123 Need_To_Create_Itype : Boolean := False;
11126 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
11127 while Present (Old_Constraint) loop
11128 Expr := Node (Old_Constraint);
11130 if Is_Discriminant (Expr) then
11131 Need_To_Create_Itype := True;
11134 Next_Elmt (Old_Constraint);
11137 if Need_To_Create_Itype then
11138 Constr_List := New_List;
11140 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
11141 while Present (Old_Constraint) loop
11142 Expr := Node (Old_Constraint);
11144 if Is_Discriminant (Expr) then
11145 Expr := Get_Discr_Value (Expr);
11148 Append (New_Copy_Tree (Expr), To => Constr_List);
11150 Next_Elmt (Old_Constraint);
11153 return Build_Subtype (Old_Type, Constr_List);
11158 end Build_Constrained_Discriminated_Type;
11160 -------------------
11161 -- Build_Subtype --
11162 -------------------
11164 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
11166 Subtyp_Decl : Node_Id;
11167 Def_Id : Entity_Id;
11168 Btyp : Entity_Id := Base_Type (T);
11171 -- The Related_Node better be here or else we won't be able to
11172 -- attach new itypes to a node in the tree.
11174 pragma Assert (Present (Related_Node));
11176 -- If the view of the component's type is incomplete or private
11177 -- with unknown discriminants, then the constraint must be applied
11178 -- to the full type.
11180 if Has_Unknown_Discriminants (Btyp)
11181 and then Present (Underlying_Type (Btyp))
11183 Btyp := Underlying_Type (Btyp);
11187 Make_Subtype_Indication (Loc,
11188 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
11189 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
11191 Def_Id := Create_Itype (Ekind (T), Related_Node);
11194 Make_Subtype_Declaration (Loc,
11195 Defining_Identifier => Def_Id,
11196 Subtype_Indication => Indic);
11198 Set_Parent (Subtyp_Decl, Parent (Related_Node));
11200 -- Itypes must be analyzed with checks off (see package Itypes)
11202 Analyze (Subtyp_Decl, Suppress => All_Checks);
11207 ---------------------
11208 -- Get_Discr_Value --
11209 ---------------------
11211 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
11216 -- The discriminant may be declared for the type, in which case we
11217 -- find it by iterating over the list of discriminants. If the
11218 -- discriminant is inherited from a parent type, it appears as the
11219 -- corresponding discriminant of the current type. This will be the
11220 -- case when constraining an inherited component whose constraint is
11221 -- given by a discriminant of the parent.
11223 D := First_Discriminant (Typ);
11224 E := First_Elmt (Constraints);
11226 while Present (D) loop
11227 if D = Entity (Discrim)
11228 or else D = CR_Discriminant (Entity (Discrim))
11229 or else Corresponding_Discriminant (D) = Entity (Discrim)
11234 Next_Discriminant (D);
11238 -- The Corresponding_Discriminant mechanism is incomplete, because
11239 -- the correspondence between new and old discriminants is not one
11240 -- to one: one new discriminant can constrain several old ones. In
11241 -- that case, scan sequentially the stored_constraint, the list of
11242 -- discriminants of the parents, and the constraints.
11243 -- Previous code checked for the present of the Stored_Constraint
11244 -- list for the derived type, but did not use it at all. Should it
11245 -- be present when the component is a discriminated task type?
11247 if Is_Derived_Type (Typ)
11248 and then Scope (Entity (Discrim)) = Etype (Typ)
11250 D := First_Discriminant (Etype (Typ));
11251 E := First_Elmt (Constraints);
11252 while Present (D) loop
11253 if D = Entity (Discrim) then
11257 Next_Discriminant (D);
11262 -- Something is wrong if we did not find the value
11264 raise Program_Error;
11265 end Get_Discr_Value;
11267 ---------------------
11268 -- Is_Discriminant --
11269 ---------------------
11271 function Is_Discriminant (Expr : Node_Id) return Boolean is
11272 Discrim_Scope : Entity_Id;
11275 if Denotes_Discriminant (Expr) then
11276 Discrim_Scope := Scope (Entity (Expr));
11278 -- Either we have a reference to one of Typ's discriminants,
11280 pragma Assert (Discrim_Scope = Typ
11282 -- or to the discriminants of the parent type, in the case
11283 -- of a derivation of a tagged type with variants.
11285 or else Discrim_Scope = Etype (Typ)
11286 or else Full_View (Discrim_Scope) = Etype (Typ)
11288 -- or same as above for the case where the discriminants
11289 -- were declared in Typ's private view.
11291 or else (Is_Private_Type (Discrim_Scope)
11292 and then Chars (Discrim_Scope) = Chars (Typ))
11294 -- or else we are deriving from the full view and the
11295 -- discriminant is declared in the private entity.
11297 or else (Is_Private_Type (Typ)
11298 and then Chars (Discrim_Scope) = Chars (Typ))
11300 -- Or we are constrained the corresponding record of a
11301 -- synchronized type that completes a private declaration.
11303 or else (Is_Concurrent_Record_Type (Typ)
11305 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
11307 -- or we have a class-wide type, in which case make sure the
11308 -- discriminant found belongs to the root type.
11310 or else (Is_Class_Wide_Type (Typ)
11311 and then Etype (Typ) = Discrim_Scope));
11316 -- In all other cases we have something wrong
11319 end Is_Discriminant;
11321 -- Start of processing for Constrain_Component_Type
11324 if Nkind (Parent (Comp)) = N_Component_Declaration
11325 and then Comes_From_Source (Parent (Comp))
11326 and then Comes_From_Source
11327 (Subtype_Indication (Component_Definition (Parent (Comp))))
11330 (Subtype_Indication (Component_Definition (Parent (Comp))))
11332 return Compon_Type;
11334 elsif Is_Array_Type (Compon_Type) then
11335 return Build_Constrained_Array_Type (Compon_Type);
11337 elsif Has_Discriminants (Compon_Type) then
11338 return Build_Constrained_Discriminated_Type (Compon_Type);
11340 elsif Is_Access_Type (Compon_Type) then
11341 return Build_Constrained_Access_Type (Compon_Type);
11344 return Compon_Type;
11346 end Constrain_Component_Type;
11348 --------------------------
11349 -- Constrain_Concurrent --
11350 --------------------------
11352 -- For concurrent types, the associated record value type carries the same
11353 -- discriminants, so when we constrain a concurrent type, we must constrain
11354 -- the corresponding record type as well.
11356 procedure Constrain_Concurrent
11357 (Def_Id : in out Entity_Id;
11359 Related_Nod : Node_Id;
11360 Related_Id : Entity_Id;
11361 Suffix : Character)
11363 -- Retrieve Base_Type to ensure getting to the concurrent type in the
11364 -- case of a private subtype (needed when only doing semantic analysis).
11366 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
11370 if Ekind (T_Ent) in Access_Kind then
11371 T_Ent := Designated_Type (T_Ent);
11374 T_Val := Corresponding_Record_Type (T_Ent);
11376 if Present (T_Val) then
11378 if No (Def_Id) then
11379 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
11382 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
11384 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
11385 Set_Corresponding_Record_Type (Def_Id,
11386 Constrain_Corresponding_Record
11387 (Def_Id, T_Val, Related_Nod, Related_Id));
11390 -- If there is no associated record, expansion is disabled and this
11391 -- is a generic context. Create a subtype in any case, so that
11392 -- semantic analysis can proceed.
11394 if No (Def_Id) then
11395 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
11398 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
11400 end Constrain_Concurrent;
11402 ------------------------------------
11403 -- Constrain_Corresponding_Record --
11404 ------------------------------------
11406 function Constrain_Corresponding_Record
11407 (Prot_Subt : Entity_Id;
11408 Corr_Rec : Entity_Id;
11409 Related_Nod : Node_Id;
11410 Related_Id : Entity_Id) return Entity_Id
11412 T_Sub : constant Entity_Id :=
11413 Create_Itype (E_Record_Subtype, Related_Nod, Related_Id, 'V');
11416 Set_Etype (T_Sub, Corr_Rec);
11417 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
11418 Set_Is_Constrained (T_Sub, True);
11419 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
11420 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
11422 -- As elsewhere, we do not want to create a freeze node for this itype
11423 -- if it is created for a constrained component of an enclosing record
11424 -- because references to outer discriminants will appear out of scope.
11426 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
11427 Conditional_Delay (T_Sub, Corr_Rec);
11429 Set_Is_Frozen (T_Sub);
11432 if Has_Discriminants (Prot_Subt) then -- False only if errors.
11433 Set_Discriminant_Constraint
11434 (T_Sub, Discriminant_Constraint (Prot_Subt));
11435 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
11436 Create_Constrained_Components
11437 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
11440 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
11443 end Constrain_Corresponding_Record;
11445 -----------------------
11446 -- Constrain_Decimal --
11447 -----------------------
11449 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
11450 T : constant Entity_Id := Entity (Subtype_Mark (S));
11451 C : constant Node_Id := Constraint (S);
11452 Loc : constant Source_Ptr := Sloc (C);
11453 Range_Expr : Node_Id;
11454 Digits_Expr : Node_Id;
11459 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
11461 if Nkind (C) = N_Range_Constraint then
11462 Range_Expr := Range_Expression (C);
11463 Digits_Val := Digits_Value (T);
11466 pragma Assert (Nkind (C) = N_Digits_Constraint);
11468 Check_SPARK_Restriction ("digits constraint is not allowed", S);
11470 Digits_Expr := Digits_Expression (C);
11471 Analyze_And_Resolve (Digits_Expr, Any_Integer);
11473 Check_Digits_Expression (Digits_Expr);
11474 Digits_Val := Expr_Value (Digits_Expr);
11476 if Digits_Val > Digits_Value (T) then
11478 ("digits expression is incompatible with subtype", C);
11479 Digits_Val := Digits_Value (T);
11482 if Present (Range_Constraint (C)) then
11483 Range_Expr := Range_Expression (Range_Constraint (C));
11485 Range_Expr := Empty;
11489 Set_Etype (Def_Id, Base_Type (T));
11490 Set_Size_Info (Def_Id, (T));
11491 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11492 Set_Delta_Value (Def_Id, Delta_Value (T));
11493 Set_Scale_Value (Def_Id, Scale_Value (T));
11494 Set_Small_Value (Def_Id, Small_Value (T));
11495 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
11496 Set_Digits_Value (Def_Id, Digits_Val);
11498 -- Manufacture range from given digits value if no range present
11500 if No (Range_Expr) then
11501 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
11505 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
11507 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
11510 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
11511 Set_Discrete_RM_Size (Def_Id);
11513 -- Unconditionally delay the freeze, since we cannot set size
11514 -- information in all cases correctly until the freeze point.
11516 Set_Has_Delayed_Freeze (Def_Id);
11517 end Constrain_Decimal;
11519 ----------------------------------
11520 -- Constrain_Discriminated_Type --
11521 ----------------------------------
11523 procedure Constrain_Discriminated_Type
11524 (Def_Id : Entity_Id;
11526 Related_Nod : Node_Id;
11527 For_Access : Boolean := False)
11529 E : constant Entity_Id := Entity (Subtype_Mark (S));
11532 Elist : Elist_Id := New_Elmt_List;
11534 procedure Fixup_Bad_Constraint;
11535 -- This is called after finding a bad constraint, and after having
11536 -- posted an appropriate error message. The mission is to leave the
11537 -- entity T in as reasonable state as possible!
11539 --------------------------
11540 -- Fixup_Bad_Constraint --
11541 --------------------------
11543 procedure Fixup_Bad_Constraint is
11545 -- Set a reasonable Ekind for the entity. For an incomplete type,
11546 -- we can't do much, but for other types, we can set the proper
11547 -- corresponding subtype kind.
11549 if Ekind (T) = E_Incomplete_Type then
11550 Set_Ekind (Def_Id, Ekind (T));
11552 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
11555 -- Set Etype to the known type, to reduce chances of cascaded errors
11557 Set_Etype (Def_Id, E);
11558 Set_Error_Posted (Def_Id);
11559 end Fixup_Bad_Constraint;
11561 -- Start of processing for Constrain_Discriminated_Type
11564 C := Constraint (S);
11566 -- A discriminant constraint is only allowed in a subtype indication,
11567 -- after a subtype mark. This subtype mark must denote either a type
11568 -- with discriminants, or an access type whose designated type is a
11569 -- type with discriminants. A discriminant constraint specifies the
11570 -- values of these discriminants (RM 3.7.2(5)).
11572 T := Base_Type (Entity (Subtype_Mark (S)));
11574 if Ekind (T) in Access_Kind then
11575 T := Designated_Type (T);
11578 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
11579 -- Avoid generating an error for access-to-incomplete subtypes.
11581 if Ada_Version >= Ada_2005
11582 and then Ekind (T) = E_Incomplete_Type
11583 and then Nkind (Parent (S)) = N_Subtype_Declaration
11584 and then not Is_Itype (Def_Id)
11586 -- A little sanity check, emit an error message if the type
11587 -- has discriminants to begin with. Type T may be a regular
11588 -- incomplete type or imported via a limited with clause.
11590 if Has_Discriminants (T)
11592 (From_With_Type (T)
11593 and then Present (Non_Limited_View (T))
11594 and then Nkind (Parent (Non_Limited_View (T))) =
11595 N_Full_Type_Declaration
11596 and then Present (Discriminant_Specifications
11597 (Parent (Non_Limited_View (T)))))
11600 ("(Ada 2005) incomplete subtype may not be constrained", C);
11602 Error_Msg_N ("invalid constraint: type has no discriminant", C);
11605 Fixup_Bad_Constraint;
11608 -- Check that the type has visible discriminants. The type may be
11609 -- a private type with unknown discriminants whose full view has
11610 -- discriminants which are invisible.
11612 elsif not Has_Discriminants (T)
11614 (Has_Unknown_Discriminants (T)
11615 and then Is_Private_Type (T))
11617 Error_Msg_N ("invalid constraint: type has no discriminant", C);
11618 Fixup_Bad_Constraint;
11621 elsif Is_Constrained (E)
11622 or else (Ekind (E) = E_Class_Wide_Subtype
11623 and then Present (Discriminant_Constraint (E)))
11625 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
11626 Fixup_Bad_Constraint;
11630 -- T may be an unconstrained subtype (e.g. a generic actual).
11631 -- Constraint applies to the base type.
11633 T := Base_Type (T);
11635 Elist := Build_Discriminant_Constraints (T, S);
11637 -- If the list returned was empty we had an error in building the
11638 -- discriminant constraint. We have also already signalled an error
11639 -- in the incomplete type case
11641 if Is_Empty_Elmt_List (Elist) then
11642 Fixup_Bad_Constraint;
11646 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
11647 end Constrain_Discriminated_Type;
11649 ---------------------------
11650 -- Constrain_Enumeration --
11651 ---------------------------
11653 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
11654 T : constant Entity_Id := Entity (Subtype_Mark (S));
11655 C : constant Node_Id := Constraint (S);
11658 Set_Ekind (Def_Id, E_Enumeration_Subtype);
11660 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
11662 Set_Etype (Def_Id, Base_Type (T));
11663 Set_Size_Info (Def_Id, (T));
11664 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11665 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
11667 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11669 Set_Discrete_RM_Size (Def_Id);
11670 end Constrain_Enumeration;
11672 ----------------------
11673 -- Constrain_Float --
11674 ----------------------
11676 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
11677 T : constant Entity_Id := Entity (Subtype_Mark (S));
11683 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
11685 Set_Etype (Def_Id, Base_Type (T));
11686 Set_Size_Info (Def_Id, (T));
11687 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11689 -- Process the constraint
11691 C := Constraint (S);
11693 -- Digits constraint present
11695 if Nkind (C) = N_Digits_Constraint then
11697 Check_SPARK_Restriction ("digits constraint is not allowed", S);
11698 Check_Restriction (No_Obsolescent_Features, C);
11700 if Warn_On_Obsolescent_Feature then
11702 ("subtype digits constraint is an " &
11703 "obsolescent feature (RM J.3(8))?", C);
11706 D := Digits_Expression (C);
11707 Analyze_And_Resolve (D, Any_Integer);
11708 Check_Digits_Expression (D);
11709 Set_Digits_Value (Def_Id, Expr_Value (D));
11711 -- Check that digits value is in range. Obviously we can do this
11712 -- at compile time, but it is strictly a runtime check, and of
11713 -- course there is an ACVC test that checks this!
11715 if Digits_Value (Def_Id) > Digits_Value (T) then
11716 Error_Msg_Uint_1 := Digits_Value (T);
11717 Error_Msg_N ("?digits value is too large, maximum is ^", D);
11719 Make_Raise_Constraint_Error (Sloc (D),
11720 Reason => CE_Range_Check_Failed);
11721 Insert_Action (Declaration_Node (Def_Id), Rais);
11724 C := Range_Constraint (C);
11726 -- No digits constraint present
11729 Set_Digits_Value (Def_Id, Digits_Value (T));
11732 -- Range constraint present
11734 if Nkind (C) = N_Range_Constraint then
11735 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11737 -- No range constraint present
11740 pragma Assert (No (C));
11741 Set_Scalar_Range (Def_Id, Scalar_Range (T));
11744 Set_Is_Constrained (Def_Id);
11745 end Constrain_Float;
11747 ---------------------
11748 -- Constrain_Index --
11749 ---------------------
11751 procedure Constrain_Index
11754 Related_Nod : Node_Id;
11755 Related_Id : Entity_Id;
11756 Suffix : Character;
11757 Suffix_Index : Nat)
11759 Def_Id : Entity_Id;
11760 R : Node_Id := Empty;
11761 T : constant Entity_Id := Etype (Index);
11764 if Nkind (S) = N_Range
11766 (Nkind (S) = N_Attribute_Reference
11767 and then Attribute_Name (S) = Name_Range)
11769 -- A Range attribute will be transformed into N_Range by Resolve
11775 Process_Range_Expr_In_Decl (R, T, Empty_List);
11777 if not Error_Posted (S)
11779 (Nkind (S) /= N_Range
11780 or else not Covers (T, (Etype (Low_Bound (S))))
11781 or else not Covers (T, (Etype (High_Bound (S)))))
11783 if Base_Type (T) /= Any_Type
11784 and then Etype (Low_Bound (S)) /= Any_Type
11785 and then Etype (High_Bound (S)) /= Any_Type
11787 Error_Msg_N ("range expected", S);
11791 elsif Nkind (S) = N_Subtype_Indication then
11793 -- The parser has verified that this is a discrete indication
11795 Resolve_Discrete_Subtype_Indication (S, T);
11796 R := Range_Expression (Constraint (S));
11798 -- Capture values of bounds and generate temporaries for them if
11799 -- needed, since checks may cause duplication of the expressions
11800 -- which must not be reevaluated.
11802 -- The forced evaluation removes side effects from expressions,
11803 -- which should occur also in Alfa mode. Otherwise, we end up with
11804 -- unexpected insertions of actions at places where this is not
11805 -- supposed to occur, e.g. on default parameters of a call.
11807 if Expander_Active then
11808 Force_Evaluation (Low_Bound (R));
11809 Force_Evaluation (High_Bound (R));
11812 elsif Nkind (S) = N_Discriminant_Association then
11814 -- Syntactically valid in subtype indication
11816 Error_Msg_N ("invalid index constraint", S);
11817 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11820 -- Subtype_Mark case, no anonymous subtypes to construct
11825 if Is_Entity_Name (S) then
11826 if not Is_Type (Entity (S)) then
11827 Error_Msg_N ("expect subtype mark for index constraint", S);
11829 elsif Base_Type (Entity (S)) /= Base_Type (T) then
11830 Wrong_Type (S, Base_Type (T));
11832 -- Check error of subtype with predicate in index constraint
11835 Bad_Predicated_Subtype_Use
11836 ("subtype& has predicate, not allowed in index constraint",
11843 Error_Msg_N ("invalid index constraint", S);
11844 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11850 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
11852 Set_Etype (Def_Id, Base_Type (T));
11854 if Is_Modular_Integer_Type (T) then
11855 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11857 elsif Is_Integer_Type (T) then
11858 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11861 Set_Ekind (Def_Id, E_Enumeration_Subtype);
11862 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
11863 Set_First_Literal (Def_Id, First_Literal (T));
11866 Set_Size_Info (Def_Id, (T));
11867 Set_RM_Size (Def_Id, RM_Size (T));
11868 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11870 Set_Scalar_Range (Def_Id, R);
11872 Set_Etype (S, Def_Id);
11873 Set_Discrete_RM_Size (Def_Id);
11874 end Constrain_Index;
11876 -----------------------
11877 -- Constrain_Integer --
11878 -----------------------
11880 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
11881 T : constant Entity_Id := Entity (Subtype_Mark (S));
11882 C : constant Node_Id := Constraint (S);
11885 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11887 if Is_Modular_Integer_Type (T) then
11888 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11890 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11893 Set_Etype (Def_Id, Base_Type (T));
11894 Set_Size_Info (Def_Id, (T));
11895 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11896 Set_Discrete_RM_Size (Def_Id);
11897 end Constrain_Integer;
11899 ------------------------------
11900 -- Constrain_Ordinary_Fixed --
11901 ------------------------------
11903 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
11904 T : constant Entity_Id := Entity (Subtype_Mark (S));
11910 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
11911 Set_Etype (Def_Id, Base_Type (T));
11912 Set_Size_Info (Def_Id, (T));
11913 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11914 Set_Small_Value (Def_Id, Small_Value (T));
11916 -- Process the constraint
11918 C := Constraint (S);
11920 -- Delta constraint present
11922 if Nkind (C) = N_Delta_Constraint then
11924 Check_SPARK_Restriction ("delta constraint is not allowed", S);
11925 Check_Restriction (No_Obsolescent_Features, C);
11927 if Warn_On_Obsolescent_Feature then
11929 ("subtype delta constraint is an " &
11930 "obsolescent feature (RM J.3(7))?");
11933 D := Delta_Expression (C);
11934 Analyze_And_Resolve (D, Any_Real);
11935 Check_Delta_Expression (D);
11936 Set_Delta_Value (Def_Id, Expr_Value_R (D));
11938 -- Check that delta value is in range. Obviously we can do this
11939 -- at compile time, but it is strictly a runtime check, and of
11940 -- course there is an ACVC test that checks this!
11942 if Delta_Value (Def_Id) < Delta_Value (T) then
11943 Error_Msg_N ("?delta value is too small", D);
11945 Make_Raise_Constraint_Error (Sloc (D),
11946 Reason => CE_Range_Check_Failed);
11947 Insert_Action (Declaration_Node (Def_Id), Rais);
11950 C := Range_Constraint (C);
11952 -- No delta constraint present
11955 Set_Delta_Value (Def_Id, Delta_Value (T));
11958 -- Range constraint present
11960 if Nkind (C) = N_Range_Constraint then
11961 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11963 -- No range constraint present
11966 pragma Assert (No (C));
11967 Set_Scalar_Range (Def_Id, Scalar_Range (T));
11971 Set_Discrete_RM_Size (Def_Id);
11973 -- Unconditionally delay the freeze, since we cannot set size
11974 -- information in all cases correctly until the freeze point.
11976 Set_Has_Delayed_Freeze (Def_Id);
11977 end Constrain_Ordinary_Fixed;
11979 -----------------------
11980 -- Contain_Interface --
11981 -----------------------
11983 function Contain_Interface
11984 (Iface : Entity_Id;
11985 Ifaces : Elist_Id) return Boolean
11987 Iface_Elmt : Elmt_Id;
11990 if Present (Ifaces) then
11991 Iface_Elmt := First_Elmt (Ifaces);
11992 while Present (Iface_Elmt) loop
11993 if Node (Iface_Elmt) = Iface then
11997 Next_Elmt (Iface_Elmt);
12002 end Contain_Interface;
12004 ---------------------------
12005 -- Convert_Scalar_Bounds --
12006 ---------------------------
12008 procedure Convert_Scalar_Bounds
12010 Parent_Type : Entity_Id;
12011 Derived_Type : Entity_Id;
12014 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
12021 -- Defend against previous errors
12023 if No (Scalar_Range (Derived_Type)) then
12027 Lo := Build_Scalar_Bound
12028 (Type_Low_Bound (Derived_Type),
12029 Parent_Type, Implicit_Base);
12031 Hi := Build_Scalar_Bound
12032 (Type_High_Bound (Derived_Type),
12033 Parent_Type, Implicit_Base);
12040 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
12042 Set_Parent (Rng, N);
12043 Set_Scalar_Range (Derived_Type, Rng);
12045 -- Analyze the bounds
12047 Analyze_And_Resolve (Lo, Implicit_Base);
12048 Analyze_And_Resolve (Hi, Implicit_Base);
12050 -- Analyze the range itself, except that we do not analyze it if
12051 -- the bounds are real literals, and we have a fixed-point type.
12052 -- The reason for this is that we delay setting the bounds in this
12053 -- case till we know the final Small and Size values (see circuit
12054 -- in Freeze.Freeze_Fixed_Point_Type for further details).
12056 if Is_Fixed_Point_Type (Parent_Type)
12057 and then Nkind (Lo) = N_Real_Literal
12058 and then Nkind (Hi) = N_Real_Literal
12062 -- Here we do the analysis of the range
12064 -- Note: we do this manually, since if we do a normal Analyze and
12065 -- Resolve call, there are problems with the conversions used for
12066 -- the derived type range.
12069 Set_Etype (Rng, Implicit_Base);
12070 Set_Analyzed (Rng, True);
12072 end Convert_Scalar_Bounds;
12074 -------------------
12075 -- Copy_And_Swap --
12076 -------------------
12078 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
12080 -- Initialize new full declaration entity by copying the pertinent
12081 -- fields of the corresponding private declaration entity.
12083 -- We temporarily set Ekind to a value appropriate for a type to
12084 -- avoid assert failures in Einfo from checking for setting type
12085 -- attributes on something that is not a type. Ekind (Priv) is an
12086 -- appropriate choice, since it allowed the attributes to be set
12087 -- in the first place. This Ekind value will be modified later.
12089 Set_Ekind (Full, Ekind (Priv));
12091 -- Also set Etype temporarily to Any_Type, again, in the absence
12092 -- of errors, it will be properly reset, and if there are errors,
12093 -- then we want a value of Any_Type to remain.
12095 Set_Etype (Full, Any_Type);
12097 -- Now start copying attributes
12099 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
12101 if Has_Discriminants (Full) then
12102 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
12103 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
12106 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
12107 Set_Homonym (Full, Homonym (Priv));
12108 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
12109 Set_Is_Public (Full, Is_Public (Priv));
12110 Set_Is_Pure (Full, Is_Pure (Priv));
12111 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
12112 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
12113 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
12114 Set_Has_Pragma_Unreferenced_Objects
12115 (Full, Has_Pragma_Unreferenced_Objects
12118 Conditional_Delay (Full, Priv);
12120 if Is_Tagged_Type (Full) then
12121 Set_Direct_Primitive_Operations (Full,
12122 Direct_Primitive_Operations (Priv));
12124 if Is_Base_Type (Priv) then
12125 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
12129 Set_Is_Volatile (Full, Is_Volatile (Priv));
12130 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
12131 Set_Scope (Full, Scope (Priv));
12132 Set_Next_Entity (Full, Next_Entity (Priv));
12133 Set_First_Entity (Full, First_Entity (Priv));
12134 Set_Last_Entity (Full, Last_Entity (Priv));
12136 -- If access types have been recorded for later handling, keep them in
12137 -- the full view so that they get handled when the full view freeze
12138 -- node is expanded.
12140 if Present (Freeze_Node (Priv))
12141 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
12143 Ensure_Freeze_Node (Full);
12144 Set_Access_Types_To_Process
12145 (Freeze_Node (Full),
12146 Access_Types_To_Process (Freeze_Node (Priv)));
12149 -- Swap the two entities. Now Private is the full type entity and Full
12150 -- is the private one. They will be swapped back at the end of the
12151 -- private part. This swapping ensures that the entity that is visible
12152 -- in the private part is the full declaration.
12154 Exchange_Entities (Priv, Full);
12155 Append_Entity (Full, Scope (Full));
12158 -------------------------------------
12159 -- Copy_Array_Base_Type_Attributes --
12160 -------------------------------------
12162 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
12164 Set_Component_Alignment (T1, Component_Alignment (T2));
12165 Set_Component_Type (T1, Component_Type (T2));
12166 Set_Component_Size (T1, Component_Size (T2));
12167 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
12168 Set_Finalize_Storage_Only (T1, Finalize_Storage_Only (T2));
12169 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
12170 Set_Has_Task (T1, Has_Task (T2));
12171 Set_Is_Packed (T1, Is_Packed (T2));
12172 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
12173 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
12174 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
12175 end Copy_Array_Base_Type_Attributes;
12177 -----------------------------------
12178 -- Copy_Array_Subtype_Attributes --
12179 -----------------------------------
12181 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
12183 Set_Size_Info (T1, T2);
12185 Set_First_Index (T1, First_Index (T2));
12186 Set_Is_Aliased (T1, Is_Aliased (T2));
12187 Set_Is_Atomic (T1, Is_Atomic (T2));
12188 Set_Is_Volatile (T1, Is_Volatile (T2));
12189 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
12190 Set_Is_Constrained (T1, Is_Constrained (T2));
12191 Set_Depends_On_Private (T1, Has_Private_Component (T2));
12192 Set_First_Rep_Item (T1, First_Rep_Item (T2));
12193 Set_Convention (T1, Convention (T2));
12194 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
12195 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
12196 Set_Packed_Array_Type (T1, Packed_Array_Type (T2));
12197 end Copy_Array_Subtype_Attributes;
12199 -----------------------------------
12200 -- Create_Constrained_Components --
12201 -----------------------------------
12203 procedure Create_Constrained_Components
12205 Decl_Node : Node_Id;
12207 Constraints : Elist_Id)
12209 Loc : constant Source_Ptr := Sloc (Subt);
12210 Comp_List : constant Elist_Id := New_Elmt_List;
12211 Parent_Type : constant Entity_Id := Etype (Typ);
12212 Assoc_List : constant List_Id := New_List;
12213 Discr_Val : Elmt_Id;
12217 Is_Static : Boolean := True;
12219 procedure Collect_Fixed_Components (Typ : Entity_Id);
12220 -- Collect parent type components that do not appear in a variant part
12222 procedure Create_All_Components;
12223 -- Iterate over Comp_List to create the components of the subtype
12225 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
12226 -- Creates a new component from Old_Compon, copying all the fields from
12227 -- it, including its Etype, inserts the new component in the Subt entity
12228 -- chain and returns the new component.
12230 function Is_Variant_Record (T : Entity_Id) return Boolean;
12231 -- If true, and discriminants are static, collect only components from
12232 -- variants selected by discriminant values.
12234 ------------------------------
12235 -- Collect_Fixed_Components --
12236 ------------------------------
12238 procedure Collect_Fixed_Components (Typ : Entity_Id) is
12240 -- Build association list for discriminants, and find components of the
12241 -- variant part selected by the values of the discriminants.
12243 Old_C := First_Discriminant (Typ);
12244 Discr_Val := First_Elmt (Constraints);
12245 while Present (Old_C) loop
12246 Append_To (Assoc_List,
12247 Make_Component_Association (Loc,
12248 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
12249 Expression => New_Copy (Node (Discr_Val))));
12251 Next_Elmt (Discr_Val);
12252 Next_Discriminant (Old_C);
12255 -- The tag and the possible parent component are unconditionally in
12258 if Is_Tagged_Type (Typ)
12259 or else Has_Controlled_Component (Typ)
12261 Old_C := First_Component (Typ);
12262 while Present (Old_C) loop
12263 if Chars ((Old_C)) = Name_uTag
12264 or else Chars ((Old_C)) = Name_uParent
12266 Append_Elmt (Old_C, Comp_List);
12269 Next_Component (Old_C);
12272 end Collect_Fixed_Components;
12274 ---------------------------
12275 -- Create_All_Components --
12276 ---------------------------
12278 procedure Create_All_Components is
12282 Comp := First_Elmt (Comp_List);
12283 while Present (Comp) loop
12284 Old_C := Node (Comp);
12285 New_C := Create_Component (Old_C);
12289 Constrain_Component_Type
12290 (Old_C, Subt, Decl_Node, Typ, Constraints));
12291 Set_Is_Public (New_C, Is_Public (Subt));
12295 end Create_All_Components;
12297 ----------------------
12298 -- Create_Component --
12299 ----------------------
12301 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
12302 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
12305 if Ekind (Old_Compon) = E_Discriminant
12306 and then Is_Completely_Hidden (Old_Compon)
12308 -- This is a shadow discriminant created for a discriminant of
12309 -- the parent type, which needs to be present in the subtype.
12310 -- Give the shadow discriminant an internal name that cannot
12311 -- conflict with that of visible components.
12313 Set_Chars (New_Compon, New_Internal_Name ('C'));
12316 -- Set the parent so we have a proper link for freezing etc. This is
12317 -- not a real parent pointer, since of course our parent does not own
12318 -- up to us and reference us, we are an illegitimate child of the
12319 -- original parent!
12321 Set_Parent (New_Compon, Parent (Old_Compon));
12323 -- If the old component's Esize was already determined and is a
12324 -- static value, then the new component simply inherits it. Otherwise
12325 -- the old component's size may require run-time determination, but
12326 -- the new component's size still might be statically determinable
12327 -- (if, for example it has a static constraint). In that case we want
12328 -- Layout_Type to recompute the component's size, so we reset its
12329 -- size and positional fields.
12331 if Frontend_Layout_On_Target
12332 and then not Known_Static_Esize (Old_Compon)
12334 Set_Esize (New_Compon, Uint_0);
12335 Init_Normalized_First_Bit (New_Compon);
12336 Init_Normalized_Position (New_Compon);
12337 Init_Normalized_Position_Max (New_Compon);
12340 -- We do not want this node marked as Comes_From_Source, since
12341 -- otherwise it would get first class status and a separate cross-
12342 -- reference line would be generated. Illegitimate children do not
12343 -- rate such recognition.
12345 Set_Comes_From_Source (New_Compon, False);
12347 -- But it is a real entity, and a birth certificate must be properly
12348 -- registered by entering it into the entity list.
12350 Enter_Name (New_Compon);
12353 end Create_Component;
12355 -----------------------
12356 -- Is_Variant_Record --
12357 -----------------------
12359 function Is_Variant_Record (T : Entity_Id) return Boolean is
12361 return Nkind (Parent (T)) = N_Full_Type_Declaration
12362 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
12363 and then Present (Component_List (Type_Definition (Parent (T))))
12366 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
12367 end Is_Variant_Record;
12369 -- Start of processing for Create_Constrained_Components
12372 pragma Assert (Subt /= Base_Type (Subt));
12373 pragma Assert (Typ = Base_Type (Typ));
12375 Set_First_Entity (Subt, Empty);
12376 Set_Last_Entity (Subt, Empty);
12378 -- Check whether constraint is fully static, in which case we can
12379 -- optimize the list of components.
12381 Discr_Val := First_Elmt (Constraints);
12382 while Present (Discr_Val) loop
12383 if not Is_OK_Static_Expression (Node (Discr_Val)) then
12384 Is_Static := False;
12388 Next_Elmt (Discr_Val);
12391 Set_Has_Static_Discriminants (Subt, Is_Static);
12395 -- Inherit the discriminants of the parent type
12397 Add_Discriminants : declare
12403 Old_C := First_Discriminant (Typ);
12405 while Present (Old_C) loop
12406 Num_Disc := Num_Disc + 1;
12407 New_C := Create_Component (Old_C);
12408 Set_Is_Public (New_C, Is_Public (Subt));
12409 Next_Discriminant (Old_C);
12412 -- For an untagged derived subtype, the number of discriminants may
12413 -- be smaller than the number of inherited discriminants, because
12414 -- several of them may be renamed by a single new discriminant or
12415 -- constrained. In this case, add the hidden discriminants back into
12416 -- the subtype, because they need to be present if the optimizer of
12417 -- the GCC 4.x back-end decides to break apart assignments between
12418 -- objects using the parent view into member-wise assignments.
12422 if Is_Derived_Type (Typ)
12423 and then not Is_Tagged_Type (Typ)
12425 Old_C := First_Stored_Discriminant (Typ);
12427 while Present (Old_C) loop
12428 Num_Gird := Num_Gird + 1;
12429 Next_Stored_Discriminant (Old_C);
12433 if Num_Gird > Num_Disc then
12435 -- Find out multiple uses of new discriminants, and add hidden
12436 -- components for the extra renamed discriminants. We recognize
12437 -- multiple uses through the Corresponding_Discriminant of a
12438 -- new discriminant: if it constrains several old discriminants,
12439 -- this field points to the last one in the parent type. The
12440 -- stored discriminants of the derived type have the same name
12441 -- as those of the parent.
12445 New_Discr : Entity_Id;
12446 Old_Discr : Entity_Id;
12449 Constr := First_Elmt (Stored_Constraint (Typ));
12450 Old_Discr := First_Stored_Discriminant (Typ);
12451 while Present (Constr) loop
12452 if Is_Entity_Name (Node (Constr))
12453 and then Ekind (Entity (Node (Constr))) = E_Discriminant
12455 New_Discr := Entity (Node (Constr));
12457 if Chars (Corresponding_Discriminant (New_Discr)) /=
12460 -- The new discriminant has been used to rename a
12461 -- subsequent old discriminant. Introduce a shadow
12462 -- component for the current old discriminant.
12464 New_C := Create_Component (Old_Discr);
12465 Set_Original_Record_Component (New_C, Old_Discr);
12469 -- The constraint has eliminated the old discriminant.
12470 -- Introduce a shadow component.
12472 New_C := Create_Component (Old_Discr);
12473 Set_Original_Record_Component (New_C, Old_Discr);
12476 Next_Elmt (Constr);
12477 Next_Stored_Discriminant (Old_Discr);
12481 end Add_Discriminants;
12484 and then Is_Variant_Record (Typ)
12486 Collect_Fixed_Components (Typ);
12488 Gather_Components (
12490 Component_List (Type_Definition (Parent (Typ))),
12491 Governed_By => Assoc_List,
12493 Report_Errors => Errors);
12494 pragma Assert (not Errors);
12496 Create_All_Components;
12498 -- If the subtype declaration is created for a tagged type derivation
12499 -- with constraints, we retrieve the record definition of the parent
12500 -- type to select the components of the proper variant.
12503 and then Is_Tagged_Type (Typ)
12504 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
12506 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
12507 and then Is_Variant_Record (Parent_Type)
12509 Collect_Fixed_Components (Typ);
12511 Gather_Components (
12513 Component_List (Type_Definition (Parent (Parent_Type))),
12514 Governed_By => Assoc_List,
12516 Report_Errors => Errors);
12517 pragma Assert (not Errors);
12519 -- If the tagged derivation has a type extension, collect all the
12520 -- new components therein.
12523 (Record_Extension_Part (Type_Definition (Parent (Typ))))
12525 Old_C := First_Component (Typ);
12526 while Present (Old_C) loop
12527 if Original_Record_Component (Old_C) = Old_C
12528 and then Chars (Old_C) /= Name_uTag
12529 and then Chars (Old_C) /= Name_uParent
12531 Append_Elmt (Old_C, Comp_List);
12534 Next_Component (Old_C);
12538 Create_All_Components;
12541 -- If discriminants are not static, or if this is a multi-level type
12542 -- extension, we have to include all components of the parent type.
12544 Old_C := First_Component (Typ);
12545 while Present (Old_C) loop
12546 New_C := Create_Component (Old_C);
12550 Constrain_Component_Type
12551 (Old_C, Subt, Decl_Node, Typ, Constraints));
12552 Set_Is_Public (New_C, Is_Public (Subt));
12554 Next_Component (Old_C);
12559 end Create_Constrained_Components;
12561 ------------------------------------------
12562 -- Decimal_Fixed_Point_Type_Declaration --
12563 ------------------------------------------
12565 procedure Decimal_Fixed_Point_Type_Declaration
12569 Loc : constant Source_Ptr := Sloc (Def);
12570 Digs_Expr : constant Node_Id := Digits_Expression (Def);
12571 Delta_Expr : constant Node_Id := Delta_Expression (Def);
12572 Implicit_Base : Entity_Id;
12579 Check_SPARK_Restriction
12580 ("decimal fixed point type is not allowed", Def);
12581 Check_Restriction (No_Fixed_Point, Def);
12583 -- Create implicit base type
12586 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
12587 Set_Etype (Implicit_Base, Implicit_Base);
12589 -- Analyze and process delta expression
12591 Analyze_And_Resolve (Delta_Expr, Universal_Real);
12593 Check_Delta_Expression (Delta_Expr);
12594 Delta_Val := Expr_Value_R (Delta_Expr);
12596 -- Check delta is power of 10, and determine scale value from it
12602 Scale_Val := Uint_0;
12605 if Val < Ureal_1 then
12606 while Val < Ureal_1 loop
12607 Val := Val * Ureal_10;
12608 Scale_Val := Scale_Val + 1;
12611 if Scale_Val > 18 then
12612 Error_Msg_N ("scale exceeds maximum value of 18", Def);
12613 Scale_Val := UI_From_Int (+18);
12617 while Val > Ureal_1 loop
12618 Val := Val / Ureal_10;
12619 Scale_Val := Scale_Val - 1;
12622 if Scale_Val < -18 then
12623 Error_Msg_N ("scale is less than minimum value of -18", Def);
12624 Scale_Val := UI_From_Int (-18);
12628 if Val /= Ureal_1 then
12629 Error_Msg_N ("delta expression must be a power of 10", Def);
12630 Delta_Val := Ureal_10 ** (-Scale_Val);
12634 -- Set delta, scale and small (small = delta for decimal type)
12636 Set_Delta_Value (Implicit_Base, Delta_Val);
12637 Set_Scale_Value (Implicit_Base, Scale_Val);
12638 Set_Small_Value (Implicit_Base, Delta_Val);
12640 -- Analyze and process digits expression
12642 Analyze_And_Resolve (Digs_Expr, Any_Integer);
12643 Check_Digits_Expression (Digs_Expr);
12644 Digs_Val := Expr_Value (Digs_Expr);
12646 if Digs_Val > 18 then
12647 Digs_Val := UI_From_Int (+18);
12648 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
12651 Set_Digits_Value (Implicit_Base, Digs_Val);
12652 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
12654 -- Set range of base type from digits value for now. This will be
12655 -- expanded to represent the true underlying base range by Freeze.
12657 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
12659 -- Note: We leave size as zero for now, size will be set at freeze
12660 -- time. We have to do this for ordinary fixed-point, because the size
12661 -- depends on the specified small, and we might as well do the same for
12662 -- decimal fixed-point.
12664 pragma Assert (Esize (Implicit_Base) = Uint_0);
12666 -- If there are bounds given in the declaration use them as the
12667 -- bounds of the first named subtype.
12669 if Present (Real_Range_Specification (Def)) then
12671 RRS : constant Node_Id := Real_Range_Specification (Def);
12672 Low : constant Node_Id := Low_Bound (RRS);
12673 High : constant Node_Id := High_Bound (RRS);
12678 Analyze_And_Resolve (Low, Any_Real);
12679 Analyze_And_Resolve (High, Any_Real);
12680 Check_Real_Bound (Low);
12681 Check_Real_Bound (High);
12682 Low_Val := Expr_Value_R (Low);
12683 High_Val := Expr_Value_R (High);
12685 if Low_Val < (-Bound_Val) then
12687 ("range low bound too small for digits value", Low);
12688 Low_Val := -Bound_Val;
12691 if High_Val > Bound_Val then
12693 ("range high bound too large for digits value", High);
12694 High_Val := Bound_Val;
12697 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
12700 -- If no explicit range, use range that corresponds to given
12701 -- digits value. This will end up as the final range for the
12705 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
12708 -- Complete entity for first subtype
12710 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
12711 Set_Etype (T, Implicit_Base);
12712 Set_Size_Info (T, Implicit_Base);
12713 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
12714 Set_Digits_Value (T, Digs_Val);
12715 Set_Delta_Value (T, Delta_Val);
12716 Set_Small_Value (T, Delta_Val);
12717 Set_Scale_Value (T, Scale_Val);
12718 Set_Is_Constrained (T);
12719 end Decimal_Fixed_Point_Type_Declaration;
12721 -----------------------------------
12722 -- Derive_Progenitor_Subprograms --
12723 -----------------------------------
12725 procedure Derive_Progenitor_Subprograms
12726 (Parent_Type : Entity_Id;
12727 Tagged_Type : Entity_Id)
12732 Iface_Elmt : Elmt_Id;
12733 Iface_Subp : Entity_Id;
12734 New_Subp : Entity_Id := Empty;
12735 Prim_Elmt : Elmt_Id;
12740 pragma Assert (Ada_Version >= Ada_2005
12741 and then Is_Record_Type (Tagged_Type)
12742 and then Is_Tagged_Type (Tagged_Type)
12743 and then Has_Interfaces (Tagged_Type));
12745 -- Step 1: Transfer to the full-view primitives associated with the
12746 -- partial-view that cover interface primitives. Conceptually this
12747 -- work should be done later by Process_Full_View; done here to
12748 -- simplify its implementation at later stages. It can be safely
12749 -- done here because interfaces must be visible in the partial and
12750 -- private view (RM 7.3(7.3/2)).
12752 -- Small optimization: This work is only required if the parent is
12753 -- abstract. If the tagged type is not abstract, it cannot have
12754 -- abstract primitives (the only entities in the list of primitives of
12755 -- non-abstract tagged types that can reference abstract primitives
12756 -- through its Alias attribute are the internal entities that have
12757 -- attribute Interface_Alias, and these entities are generated later
12758 -- by Add_Internal_Interface_Entities).
12760 if In_Private_Part (Current_Scope)
12761 and then Is_Abstract_Type (Parent_Type)
12763 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
12764 while Present (Elmt) loop
12765 Subp := Node (Elmt);
12767 -- At this stage it is not possible to have entities in the list
12768 -- of primitives that have attribute Interface_Alias
12770 pragma Assert (No (Interface_Alias (Subp)));
12772 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
12774 if Is_Interface (Typ) then
12775 E := Find_Primitive_Covering_Interface
12776 (Tagged_Type => Tagged_Type,
12777 Iface_Prim => Subp);
12780 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
12782 Replace_Elmt (Elmt, E);
12783 Remove_Homonym (Subp);
12791 -- Step 2: Add primitives of progenitors that are not implemented by
12792 -- parents of Tagged_Type
12794 if Present (Interfaces (Base_Type (Tagged_Type))) then
12795 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
12796 while Present (Iface_Elmt) loop
12797 Iface := Node (Iface_Elmt);
12799 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
12800 while Present (Prim_Elmt) loop
12801 Iface_Subp := Node (Prim_Elmt);
12803 -- Exclude derivation of predefined primitives except those
12804 -- that come from source. Required to catch declarations of
12805 -- equality operators of interfaces. For example:
12807 -- type Iface is interface;
12808 -- function "=" (Left, Right : Iface) return Boolean;
12810 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
12811 or else Comes_From_Source (Iface_Subp)
12813 E := Find_Primitive_Covering_Interface
12814 (Tagged_Type => Tagged_Type,
12815 Iface_Prim => Iface_Subp);
12817 -- If not found we derive a new primitive leaving its alias
12818 -- attribute referencing the interface primitive
12822 (New_Subp, Iface_Subp, Tagged_Type, Iface);
12824 -- Ada 2012 (AI05-0197): If the covering primitive's name
12825 -- differs from the name of the interface primitive then it
12826 -- is a private primitive inherited from a parent type. In
12827 -- such case, given that Tagged_Type covers the interface,
12828 -- the inherited private primitive becomes visible. For such
12829 -- purpose we add a new entity that renames the inherited
12830 -- private primitive.
12832 elsif Chars (E) /= Chars (Iface_Subp) then
12833 pragma Assert (Has_Suffix (E, 'P'));
12835 (New_Subp, Iface_Subp, Tagged_Type, Iface);
12836 Set_Alias (New_Subp, E);
12837 Set_Is_Abstract_Subprogram (New_Subp,
12838 Is_Abstract_Subprogram (E));
12840 -- Propagate to the full view interface entities associated
12841 -- with the partial view
12843 elsif In_Private_Part (Current_Scope)
12844 and then Present (Alias (E))
12845 and then Alias (E) = Iface_Subp
12847 List_Containing (Parent (E)) /=
12848 Private_Declarations
12850 (Unit_Declaration_Node (Current_Scope)))
12852 Append_Elmt (E, Primitive_Operations (Tagged_Type));
12856 Next_Elmt (Prim_Elmt);
12859 Next_Elmt (Iface_Elmt);
12862 end Derive_Progenitor_Subprograms;
12864 -----------------------
12865 -- Derive_Subprogram --
12866 -----------------------
12868 procedure Derive_Subprogram
12869 (New_Subp : in out Entity_Id;
12870 Parent_Subp : Entity_Id;
12871 Derived_Type : Entity_Id;
12872 Parent_Type : Entity_Id;
12873 Actual_Subp : Entity_Id := Empty)
12875 Formal : Entity_Id;
12876 -- Formal parameter of parent primitive operation
12878 Formal_Of_Actual : Entity_Id;
12879 -- Formal parameter of actual operation, when the derivation is to
12880 -- create a renaming for a primitive operation of an actual in an
12883 New_Formal : Entity_Id;
12884 -- Formal of inherited operation
12886 Visible_Subp : Entity_Id := Parent_Subp;
12888 function Is_Private_Overriding return Boolean;
12889 -- If Subp is a private overriding of a visible operation, the inherited
12890 -- operation derives from the overridden op (even though its body is the
12891 -- overriding one) and the inherited operation is visible now. See
12892 -- sem_disp to see the full details of the handling of the overridden
12893 -- subprogram, which is removed from the list of primitive operations of
12894 -- the type. The overridden subprogram is saved locally in Visible_Subp,
12895 -- and used to diagnose abstract operations that need overriding in the
12898 procedure Replace_Type (Id, New_Id : Entity_Id);
12899 -- When the type is an anonymous access type, create a new access type
12900 -- designating the derived type.
12902 procedure Set_Derived_Name;
12903 -- This procedure sets the appropriate Chars name for New_Subp. This
12904 -- is normally just a copy of the parent name. An exception arises for
12905 -- type support subprograms, where the name is changed to reflect the
12906 -- name of the derived type, e.g. if type foo is derived from type bar,
12907 -- then a procedure barDA is derived with a name fooDA.
12909 ---------------------------
12910 -- Is_Private_Overriding --
12911 ---------------------------
12913 function Is_Private_Overriding return Boolean is
12917 -- If the parent is not a dispatching operation there is no
12918 -- need to investigate overridings
12920 if not Is_Dispatching_Operation (Parent_Subp) then
12924 -- The visible operation that is overridden is a homonym of the
12925 -- parent subprogram. We scan the homonym chain to find the one
12926 -- whose alias is the subprogram we are deriving.
12928 Prev := Current_Entity (Parent_Subp);
12929 while Present (Prev) loop
12930 if Ekind (Prev) = Ekind (Parent_Subp)
12931 and then Alias (Prev) = Parent_Subp
12932 and then Scope (Parent_Subp) = Scope (Prev)
12933 and then not Is_Hidden (Prev)
12935 Visible_Subp := Prev;
12939 Prev := Homonym (Prev);
12943 end Is_Private_Overriding;
12949 procedure Replace_Type (Id, New_Id : Entity_Id) is
12950 Acc_Type : Entity_Id;
12951 Par : constant Node_Id := Parent (Derived_Type);
12954 -- When the type is an anonymous access type, create a new access
12955 -- type designating the derived type. This itype must be elaborated
12956 -- at the point of the derivation, not on subsequent calls that may
12957 -- be out of the proper scope for Gigi, so we insert a reference to
12958 -- it after the derivation.
12960 if Ekind (Etype (Id)) = E_Anonymous_Access_Type then
12962 Desig_Typ : Entity_Id := Designated_Type (Etype (Id));
12965 if Ekind (Desig_Typ) = E_Record_Type_With_Private
12966 and then Present (Full_View (Desig_Typ))
12967 and then not Is_Private_Type (Parent_Type)
12969 Desig_Typ := Full_View (Desig_Typ);
12972 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
12974 -- Ada 2005 (AI-251): Handle also derivations of abstract
12975 -- interface primitives.
12977 or else (Is_Interface (Desig_Typ)
12978 and then not Is_Class_Wide_Type (Desig_Typ))
12980 Acc_Type := New_Copy (Etype (Id));
12981 Set_Etype (Acc_Type, Acc_Type);
12982 Set_Scope (Acc_Type, New_Subp);
12984 -- Compute size of anonymous access type
12986 if Is_Array_Type (Desig_Typ)
12987 and then not Is_Constrained (Desig_Typ)
12989 Init_Size (Acc_Type, 2 * System_Address_Size);
12991 Init_Size (Acc_Type, System_Address_Size);
12994 Init_Alignment (Acc_Type);
12995 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
12997 Set_Etype (New_Id, Acc_Type);
12998 Set_Scope (New_Id, New_Subp);
13000 -- Create a reference to it
13001 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
13004 Set_Etype (New_Id, Etype (Id));
13008 elsif Base_Type (Etype (Id)) = Base_Type (Parent_Type)
13010 (Ekind (Etype (Id)) = E_Record_Type_With_Private
13011 and then Present (Full_View (Etype (Id)))
13013 Base_Type (Full_View (Etype (Id))) = Base_Type (Parent_Type))
13015 -- Constraint checks on formals are generated during expansion,
13016 -- based on the signature of the original subprogram. The bounds
13017 -- of the derived type are not relevant, and thus we can use
13018 -- the base type for the formals. However, the return type may be
13019 -- used in a context that requires that the proper static bounds
13020 -- be used (a case statement, for example) and for those cases
13021 -- we must use the derived type (first subtype), not its base.
13023 -- If the derived_type_definition has no constraints, we know that
13024 -- the derived type has the same constraints as the first subtype
13025 -- of the parent, and we can also use it rather than its base,
13026 -- which can lead to more efficient code.
13028 if Etype (Id) = Parent_Type then
13029 if Is_Scalar_Type (Parent_Type)
13031 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
13033 Set_Etype (New_Id, Derived_Type);
13035 elsif Nkind (Par) = N_Full_Type_Declaration
13037 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
13040 (Subtype_Indication (Type_Definition (Par)))
13042 Set_Etype (New_Id, Derived_Type);
13045 Set_Etype (New_Id, Base_Type (Derived_Type));
13049 Set_Etype (New_Id, Base_Type (Derived_Type));
13053 Set_Etype (New_Id, Etype (Id));
13057 ----------------------
13058 -- Set_Derived_Name --
13059 ----------------------
13061 procedure Set_Derived_Name is
13062 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
13064 if Nm = TSS_Null then
13065 Set_Chars (New_Subp, Chars (Parent_Subp));
13067 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
13069 end Set_Derived_Name;
13071 -- Start of processing for Derive_Subprogram
13075 New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
13076 Set_Ekind (New_Subp, Ekind (Parent_Subp));
13077 Set_Contract (New_Subp, Make_Contract (Sloc (New_Subp)));
13079 -- Check whether the inherited subprogram is a private operation that
13080 -- should be inherited but not yet made visible. Such subprograms can
13081 -- become visible at a later point (e.g., the private part of a public
13082 -- child unit) via Declare_Inherited_Private_Subprograms. If the
13083 -- following predicate is true, then this is not such a private
13084 -- operation and the subprogram simply inherits the name of the parent
13085 -- subprogram. Note the special check for the names of controlled
13086 -- operations, which are currently exempted from being inherited with
13087 -- a hidden name because they must be findable for generation of
13088 -- implicit run-time calls.
13090 if not Is_Hidden (Parent_Subp)
13091 or else Is_Internal (Parent_Subp)
13092 or else Is_Private_Overriding
13093 or else Is_Internal_Name (Chars (Parent_Subp))
13094 or else Chars (Parent_Subp) = Name_Initialize
13095 or else Chars (Parent_Subp) = Name_Adjust
13096 or else Chars (Parent_Subp) = Name_Finalize
13100 -- An inherited dispatching equality will be overridden by an internally
13101 -- generated one, or by an explicit one, so preserve its name and thus
13102 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
13103 -- private operation it may become invisible if the full view has
13104 -- progenitors, and the dispatch table will be malformed.
13105 -- We check that the type is limited to handle the anomalous declaration
13106 -- of Limited_Controlled, which is derived from a non-limited type, and
13107 -- which is handled specially elsewhere as well.
13109 elsif Chars (Parent_Subp) = Name_Op_Eq
13110 and then Is_Dispatching_Operation (Parent_Subp)
13111 and then Etype (Parent_Subp) = Standard_Boolean
13112 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
13114 Etype (First_Formal (Parent_Subp)) =
13115 Etype (Next_Formal (First_Formal (Parent_Subp)))
13119 -- If parent is hidden, this can be a regular derivation if the
13120 -- parent is immediately visible in a non-instantiating context,
13121 -- or if we are in the private part of an instance. This test
13122 -- should still be refined ???
13124 -- The test for In_Instance_Not_Visible avoids inheriting the derived
13125 -- operation as a non-visible operation in cases where the parent
13126 -- subprogram might not be visible now, but was visible within the
13127 -- original generic, so it would be wrong to make the inherited
13128 -- subprogram non-visible now. (Not clear if this test is fully
13129 -- correct; are there any cases where we should declare the inherited
13130 -- operation as not visible to avoid it being overridden, e.g., when
13131 -- the parent type is a generic actual with private primitives ???)
13133 -- (they should be treated the same as other private inherited
13134 -- subprograms, but it's not clear how to do this cleanly). ???
13136 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
13137 and then Is_Immediately_Visible (Parent_Subp)
13138 and then not In_Instance)
13139 or else In_Instance_Not_Visible
13143 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
13144 -- overrides an interface primitive because interface primitives
13145 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
13147 elsif Ada_Version >= Ada_2005
13148 and then Is_Dispatching_Operation (Parent_Subp)
13149 and then Covers_Some_Interface (Parent_Subp)
13153 -- Otherwise, the type is inheriting a private operation, so enter
13154 -- it with a special name so it can't be overridden.
13157 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
13160 Set_Parent (New_Subp, Parent (Derived_Type));
13162 if Present (Actual_Subp) then
13163 Replace_Type (Actual_Subp, New_Subp);
13165 Replace_Type (Parent_Subp, New_Subp);
13168 Conditional_Delay (New_Subp, Parent_Subp);
13170 -- If we are creating a renaming for a primitive operation of an
13171 -- actual of a generic derived type, we must examine the signature
13172 -- of the actual primitive, not that of the generic formal, which for
13173 -- example may be an interface. However the name and initial value
13174 -- of the inherited operation are those of the formal primitive.
13176 Formal := First_Formal (Parent_Subp);
13178 if Present (Actual_Subp) then
13179 Formal_Of_Actual := First_Formal (Actual_Subp);
13181 Formal_Of_Actual := Empty;
13184 while Present (Formal) loop
13185 New_Formal := New_Copy (Formal);
13187 -- Normally we do not go copying parents, but in the case of
13188 -- formals, we need to link up to the declaration (which is the
13189 -- parameter specification), and it is fine to link up to the
13190 -- original formal's parameter specification in this case.
13192 Set_Parent (New_Formal, Parent (Formal));
13193 Append_Entity (New_Formal, New_Subp);
13195 if Present (Formal_Of_Actual) then
13196 Replace_Type (Formal_Of_Actual, New_Formal);
13197 Next_Formal (Formal_Of_Actual);
13199 Replace_Type (Formal, New_Formal);
13202 Next_Formal (Formal);
13205 -- If this derivation corresponds to a tagged generic actual, then
13206 -- primitive operations rename those of the actual. Otherwise the
13207 -- primitive operations rename those of the parent type, If the parent
13208 -- renames an intrinsic operator, so does the new subprogram. We except
13209 -- concatenation, which is always properly typed, and does not get
13210 -- expanded as other intrinsic operations.
13212 if No (Actual_Subp) then
13213 if Is_Intrinsic_Subprogram (Parent_Subp) then
13214 Set_Is_Intrinsic_Subprogram (New_Subp);
13216 if Present (Alias (Parent_Subp))
13217 and then Chars (Parent_Subp) /= Name_Op_Concat
13219 Set_Alias (New_Subp, Alias (Parent_Subp));
13221 Set_Alias (New_Subp, Parent_Subp);
13225 Set_Alias (New_Subp, Parent_Subp);
13229 Set_Alias (New_Subp, Actual_Subp);
13232 -- Derived subprograms of a tagged type must inherit the convention
13233 -- of the parent subprogram (a requirement of AI-117). Derived
13234 -- subprograms of untagged types simply get convention Ada by default.
13236 if Is_Tagged_Type (Derived_Type) then
13237 Set_Convention (New_Subp, Convention (Parent_Subp));
13240 -- Predefined controlled operations retain their name even if the parent
13241 -- is hidden (see above), but they are not primitive operations if the
13242 -- ancestor is not visible, for example if the parent is a private
13243 -- extension completed with a controlled extension. Note that a full
13244 -- type that is controlled can break privacy: the flag Is_Controlled is
13245 -- set on both views of the type.
13247 if Is_Controlled (Parent_Type)
13249 (Chars (Parent_Subp) = Name_Initialize
13250 or else Chars (Parent_Subp) = Name_Adjust
13251 or else Chars (Parent_Subp) = Name_Finalize)
13252 and then Is_Hidden (Parent_Subp)
13253 and then not Is_Visibly_Controlled (Parent_Type)
13255 Set_Is_Hidden (New_Subp);
13258 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
13259 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
13261 if Ekind (Parent_Subp) = E_Procedure then
13262 Set_Is_Valued_Procedure
13263 (New_Subp, Is_Valued_Procedure (Parent_Subp));
13265 Set_Has_Controlling_Result
13266 (New_Subp, Has_Controlling_Result (Parent_Subp));
13269 -- No_Return must be inherited properly. If this is overridden in the
13270 -- case of a dispatching operation, then a check is made in Sem_Disp
13271 -- that the overriding operation is also No_Return (no such check is
13272 -- required for the case of non-dispatching operation.
13274 Set_No_Return (New_Subp, No_Return (Parent_Subp));
13276 -- A derived function with a controlling result is abstract. If the
13277 -- Derived_Type is a nonabstract formal generic derived type, then
13278 -- inherited operations are not abstract: the required check is done at
13279 -- instantiation time. If the derivation is for a generic actual, the
13280 -- function is not abstract unless the actual is.
13282 if Is_Generic_Type (Derived_Type)
13283 and then not Is_Abstract_Type (Derived_Type)
13287 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
13288 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
13290 elsif Ada_Version >= Ada_2005
13291 and then (Is_Abstract_Subprogram (Alias (New_Subp))
13292 or else (Is_Tagged_Type (Derived_Type)
13293 and then Etype (New_Subp) = Derived_Type
13294 and then not Is_Null_Extension (Derived_Type))
13295 or else (Is_Tagged_Type (Derived_Type)
13296 and then Ekind (Etype (New_Subp)) =
13297 E_Anonymous_Access_Type
13298 and then Designated_Type (Etype (New_Subp)) =
13300 and then not Is_Null_Extension (Derived_Type)))
13301 and then No (Actual_Subp)
13303 if not Is_Tagged_Type (Derived_Type)
13304 or else Is_Abstract_Type (Derived_Type)
13305 or else Is_Abstract_Subprogram (Alias (New_Subp))
13307 Set_Is_Abstract_Subprogram (New_Subp);
13309 Set_Requires_Overriding (New_Subp);
13312 elsif Ada_Version < Ada_2005
13313 and then (Is_Abstract_Subprogram (Alias (New_Subp))
13314 or else (Is_Tagged_Type (Derived_Type)
13315 and then Etype (New_Subp) = Derived_Type
13316 and then No (Actual_Subp)))
13318 Set_Is_Abstract_Subprogram (New_Subp);
13320 -- AI05-0097 : an inherited operation that dispatches on result is
13321 -- abstract if the derived type is abstract, even if the parent type
13322 -- is concrete and the derived type is a null extension.
13324 elsif Has_Controlling_Result (Alias (New_Subp))
13325 and then Is_Abstract_Type (Etype (New_Subp))
13327 Set_Is_Abstract_Subprogram (New_Subp);
13329 -- Finally, if the parent type is abstract we must verify that all
13330 -- inherited operations are either non-abstract or overridden, or that
13331 -- the derived type itself is abstract (this check is performed at the
13332 -- end of a package declaration, in Check_Abstract_Overriding). A
13333 -- private overriding in the parent type will not be visible in the
13334 -- derivation if we are not in an inner package or in a child unit of
13335 -- the parent type, in which case the abstractness of the inherited
13336 -- operation is carried to the new subprogram.
13338 elsif Is_Abstract_Type (Parent_Type)
13339 and then not In_Open_Scopes (Scope (Parent_Type))
13340 and then Is_Private_Overriding
13341 and then Is_Abstract_Subprogram (Visible_Subp)
13343 if No (Actual_Subp) then
13344 Set_Alias (New_Subp, Visible_Subp);
13345 Set_Is_Abstract_Subprogram (New_Subp, True);
13348 -- If this is a derivation for an instance of a formal derived
13349 -- type, abstractness comes from the primitive operation of the
13350 -- actual, not from the operation inherited from the ancestor.
13352 Set_Is_Abstract_Subprogram
13353 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
13357 New_Overloaded_Entity (New_Subp, Derived_Type);
13359 -- Check for case of a derived subprogram for the instantiation of a
13360 -- formal derived tagged type, if so mark the subprogram as dispatching
13361 -- and inherit the dispatching attributes of the actual subprogram. The
13362 -- derived subprogram is effectively renaming of the actual subprogram,
13363 -- so it needs to have the same attributes as the actual.
13365 if Present (Actual_Subp)
13366 and then Is_Dispatching_Operation (Actual_Subp)
13368 Set_Is_Dispatching_Operation (New_Subp);
13370 if Present (DTC_Entity (Actual_Subp)) then
13371 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
13372 Set_DT_Position (New_Subp, DT_Position (Actual_Subp));
13376 -- Indicate that a derived subprogram does not require a body and that
13377 -- it does not require processing of default expressions.
13379 Set_Has_Completion (New_Subp);
13380 Set_Default_Expressions_Processed (New_Subp);
13382 if Ekind (New_Subp) = E_Function then
13383 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
13385 end Derive_Subprogram;
13387 ------------------------
13388 -- Derive_Subprograms --
13389 ------------------------
13391 procedure Derive_Subprograms
13392 (Parent_Type : Entity_Id;
13393 Derived_Type : Entity_Id;
13394 Generic_Actual : Entity_Id := Empty)
13396 Op_List : constant Elist_Id :=
13397 Collect_Primitive_Operations (Parent_Type);
13399 function Check_Derived_Type return Boolean;
13400 -- Check that all the entities derived from Parent_Type are found in
13401 -- the list of primitives of Derived_Type exactly in the same order.
13403 procedure Derive_Interface_Subprogram
13404 (New_Subp : in out Entity_Id;
13406 Actual_Subp : Entity_Id);
13407 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
13408 -- (which is an interface primitive). If Generic_Actual is present then
13409 -- Actual_Subp is the actual subprogram corresponding with the generic
13410 -- subprogram Subp.
13412 function Check_Derived_Type return Boolean is
13416 New_Subp : Entity_Id;
13421 -- Traverse list of entities in the current scope searching for
13422 -- an incomplete type whose full-view is derived type
13424 E := First_Entity (Scope (Derived_Type));
13426 and then E /= Derived_Type
13428 if Ekind (E) = E_Incomplete_Type
13429 and then Present (Full_View (E))
13430 and then Full_View (E) = Derived_Type
13432 -- Disable this test if Derived_Type completes an incomplete
13433 -- type because in such case more primitives can be added
13434 -- later to the list of primitives of Derived_Type by routine
13435 -- Process_Incomplete_Dependents
13440 E := Next_Entity (E);
13443 List := Collect_Primitive_Operations (Derived_Type);
13444 Elmt := First_Elmt (List);
13446 Op_Elmt := First_Elmt (Op_List);
13447 while Present (Op_Elmt) loop
13448 Subp := Node (Op_Elmt);
13449 New_Subp := Node (Elmt);
13451 -- At this early stage Derived_Type has no entities with attribute
13452 -- Interface_Alias. In addition, such primitives are always
13453 -- located at the end of the list of primitives of Parent_Type.
13454 -- Therefore, if found we can safely stop processing pending
13457 exit when Present (Interface_Alias (Subp));
13459 -- Handle hidden entities
13461 if not Is_Predefined_Dispatching_Operation (Subp)
13462 and then Is_Hidden (Subp)
13464 if Present (New_Subp)
13465 and then Primitive_Names_Match (Subp, New_Subp)
13471 if not Present (New_Subp)
13472 or else Ekind (Subp) /= Ekind (New_Subp)
13473 or else not Primitive_Names_Match (Subp, New_Subp)
13481 Next_Elmt (Op_Elmt);
13485 end Check_Derived_Type;
13487 ---------------------------------
13488 -- Derive_Interface_Subprogram --
13489 ---------------------------------
13491 procedure Derive_Interface_Subprogram
13492 (New_Subp : in out Entity_Id;
13494 Actual_Subp : Entity_Id)
13496 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
13497 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
13500 pragma Assert (Is_Interface (Iface_Type));
13503 (New_Subp => New_Subp,
13504 Parent_Subp => Iface_Subp,
13505 Derived_Type => Derived_Type,
13506 Parent_Type => Iface_Type,
13507 Actual_Subp => Actual_Subp);
13509 -- Given that this new interface entity corresponds with a primitive
13510 -- of the parent that was not overridden we must leave it associated
13511 -- with its parent primitive to ensure that it will share the same
13512 -- dispatch table slot when overridden.
13514 if No (Actual_Subp) then
13515 Set_Alias (New_Subp, Subp);
13517 -- For instantiations this is not needed since the previous call to
13518 -- Derive_Subprogram leaves the entity well decorated.
13521 pragma Assert (Alias (New_Subp) = Actual_Subp);
13524 end Derive_Interface_Subprogram;
13528 Alias_Subp : Entity_Id;
13529 Act_List : Elist_Id;
13530 Act_Elmt : Elmt_Id := No_Elmt;
13531 Act_Subp : Entity_Id := Empty;
13533 Need_Search : Boolean := False;
13534 New_Subp : Entity_Id := Empty;
13535 Parent_Base : Entity_Id;
13538 -- Start of processing for Derive_Subprograms
13541 if Ekind (Parent_Type) = E_Record_Type_With_Private
13542 and then Has_Discriminants (Parent_Type)
13543 and then Present (Full_View (Parent_Type))
13545 Parent_Base := Full_View (Parent_Type);
13547 Parent_Base := Parent_Type;
13550 if Present (Generic_Actual) then
13551 Act_List := Collect_Primitive_Operations (Generic_Actual);
13552 Act_Elmt := First_Elmt (Act_List);
13555 -- Derive primitives inherited from the parent. Note that if the generic
13556 -- actual is present, this is not really a type derivation, it is a
13557 -- completion within an instance.
13559 -- Case 1: Derived_Type does not implement interfaces
13561 if not Is_Tagged_Type (Derived_Type)
13562 or else (not Has_Interfaces (Derived_Type)
13563 and then not (Present (Generic_Actual)
13565 Has_Interfaces (Generic_Actual)))
13567 Elmt := First_Elmt (Op_List);
13568 while Present (Elmt) loop
13569 Subp := Node (Elmt);
13571 -- Literals are derived earlier in the process of building the
13572 -- derived type, and are skipped here.
13574 if Ekind (Subp) = E_Enumeration_Literal then
13577 -- The actual is a direct descendant and the common primitive
13578 -- operations appear in the same order.
13580 -- If the generic parent type is present, the derived type is an
13581 -- instance of a formal derived type, and within the instance its
13582 -- operations are those of the actual. We derive from the formal
13583 -- type but make the inherited operations aliases of the
13584 -- corresponding operations of the actual.
13587 pragma Assert (No (Node (Act_Elmt))
13588 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
13590 Type_Conformant (Subp, Node (Act_Elmt),
13591 Skip_Controlling_Formals => True)));
13594 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
13596 if Present (Act_Elmt) then
13597 Next_Elmt (Act_Elmt);
13604 -- Case 2: Derived_Type implements interfaces
13607 -- If the parent type has no predefined primitives we remove
13608 -- predefined primitives from the list of primitives of generic
13609 -- actual to simplify the complexity of this algorithm.
13611 if Present (Generic_Actual) then
13613 Has_Predefined_Primitives : Boolean := False;
13616 -- Check if the parent type has predefined primitives
13618 Elmt := First_Elmt (Op_List);
13619 while Present (Elmt) loop
13620 Subp := Node (Elmt);
13622 if Is_Predefined_Dispatching_Operation (Subp)
13623 and then not Comes_From_Source (Ultimate_Alias (Subp))
13625 Has_Predefined_Primitives := True;
13632 -- Remove predefined primitives of Generic_Actual. We must use
13633 -- an auxiliary list because in case of tagged types the value
13634 -- returned by Collect_Primitive_Operations is the value stored
13635 -- in its Primitive_Operations attribute (and we don't want to
13636 -- modify its current contents).
13638 if not Has_Predefined_Primitives then
13640 Aux_List : constant Elist_Id := New_Elmt_List;
13643 Elmt := First_Elmt (Act_List);
13644 while Present (Elmt) loop
13645 Subp := Node (Elmt);
13647 if not Is_Predefined_Dispatching_Operation (Subp)
13648 or else Comes_From_Source (Subp)
13650 Append_Elmt (Subp, Aux_List);
13656 Act_List := Aux_List;
13660 Act_Elmt := First_Elmt (Act_List);
13661 Act_Subp := Node (Act_Elmt);
13665 -- Stage 1: If the generic actual is not present we derive the
13666 -- primitives inherited from the parent type. If the generic parent
13667 -- type is present, the derived type is an instance of a formal
13668 -- derived type, and within the instance its operations are those of
13669 -- the actual. We derive from the formal type but make the inherited
13670 -- operations aliases of the corresponding operations of the actual.
13672 Elmt := First_Elmt (Op_List);
13673 while Present (Elmt) loop
13674 Subp := Node (Elmt);
13675 Alias_Subp := Ultimate_Alias (Subp);
13677 -- Do not derive internal entities of the parent that link
13678 -- interface primitives with their covering primitive. These
13679 -- entities will be added to this type when frozen.
13681 if Present (Interface_Alias (Subp)) then
13685 -- If the generic actual is present find the corresponding
13686 -- operation in the generic actual. If the parent type is a
13687 -- direct ancestor of the derived type then, even if it is an
13688 -- interface, the operations are inherited from the primary
13689 -- dispatch table and are in the proper order. If we detect here
13690 -- that primitives are not in the same order we traverse the list
13691 -- of primitive operations of the actual to find the one that
13692 -- implements the interface primitive.
13696 (Present (Generic_Actual)
13697 and then Present (Act_Subp)
13699 (Primitive_Names_Match (Subp, Act_Subp)
13701 Type_Conformant (Subp, Act_Subp,
13702 Skip_Controlling_Formals => True)))
13704 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
13705 Use_Full_View => True));
13707 -- Remember that we need searching for all pending primitives
13709 Need_Search := True;
13711 -- Handle entities associated with interface primitives
13713 if Present (Alias_Subp)
13714 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
13715 and then not Is_Predefined_Dispatching_Operation (Subp)
13717 -- Search for the primitive in the homonym chain
13720 Find_Primitive_Covering_Interface
13721 (Tagged_Type => Generic_Actual,
13722 Iface_Prim => Alias_Subp);
13724 -- Previous search may not locate primitives covering
13725 -- interfaces defined in generics units or instantiations.
13726 -- (it fails if the covering primitive has formals whose
13727 -- type is also defined in generics or instantiations).
13728 -- In such case we search in the list of primitives of the
13729 -- generic actual for the internal entity that links the
13730 -- interface primitive and the covering primitive.
13733 and then Is_Generic_Type (Parent_Type)
13735 -- This code has been designed to handle only generic
13736 -- formals that implement interfaces that are defined
13737 -- in a generic unit or instantiation. If this code is
13738 -- needed for other cases we must review it because
13739 -- (given that it relies on Original_Location to locate
13740 -- the primitive of Generic_Actual that covers the
13741 -- interface) it could leave linked through attribute
13742 -- Alias entities of unrelated instantiations).
13746 (Scope (Find_Dispatching_Type (Alias_Subp)))
13748 Instantiation_Depth
13749 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
13752 Iface_Prim_Loc : constant Source_Ptr :=
13753 Original_Location (Sloc (Alias_Subp));
13758 First_Elmt (Primitive_Operations (Generic_Actual));
13760 Search : while Present (Elmt) loop
13761 Prim := Node (Elmt);
13763 if Present (Interface_Alias (Prim))
13764 and then Original_Location
13765 (Sloc (Interface_Alias (Prim)))
13768 Act_Subp := Alias (Prim);
13777 pragma Assert (Present (Act_Subp)
13778 or else Is_Abstract_Type (Generic_Actual)
13779 or else Serious_Errors_Detected > 0);
13781 -- Handle predefined primitives plus the rest of user-defined
13785 Act_Elmt := First_Elmt (Act_List);
13786 while Present (Act_Elmt) loop
13787 Act_Subp := Node (Act_Elmt);
13789 exit when Primitive_Names_Match (Subp, Act_Subp)
13790 and then Type_Conformant
13792 Skip_Controlling_Formals => True)
13793 and then No (Interface_Alias (Act_Subp));
13795 Next_Elmt (Act_Elmt);
13798 if No (Act_Elmt) then
13804 -- Case 1: If the parent is a limited interface then it has the
13805 -- predefined primitives of synchronized interfaces. However, the
13806 -- actual type may be a non-limited type and hence it does not
13807 -- have such primitives.
13809 if Present (Generic_Actual)
13810 and then not Present (Act_Subp)
13811 and then Is_Limited_Interface (Parent_Base)
13812 and then Is_Predefined_Interface_Primitive (Subp)
13816 -- Case 2: Inherit entities associated with interfaces that were
13817 -- not covered by the parent type. We exclude here null interface
13818 -- primitives because they do not need special management.
13820 -- We also exclude interface operations that are renamings. If the
13821 -- subprogram is an explicit renaming of an interface primitive,
13822 -- it is a regular primitive operation, and the presence of its
13823 -- alias is not relevant: it has to be derived like any other
13826 elsif Present (Alias (Subp))
13827 and then Nkind (Unit_Declaration_Node (Subp)) /=
13828 N_Subprogram_Renaming_Declaration
13829 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
13831 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
13832 and then Null_Present (Parent (Alias_Subp)))
13834 -- If this is an abstract private type then we transfer the
13835 -- derivation of the interface primitive from the partial view
13836 -- to the full view. This is safe because all the interfaces
13837 -- must be visible in the partial view. Done to avoid adding
13838 -- a new interface derivation to the private part of the
13839 -- enclosing package; otherwise this new derivation would be
13840 -- decorated as hidden when the analysis of the enclosing
13841 -- package completes.
13843 if Is_Abstract_Type (Derived_Type)
13844 and then In_Private_Part (Current_Scope)
13845 and then Has_Private_Declaration (Derived_Type)
13848 Partial_View : Entity_Id;
13853 Partial_View := First_Entity (Current_Scope);
13855 exit when No (Partial_View)
13856 or else (Has_Private_Declaration (Partial_View)
13858 Full_View (Partial_View) = Derived_Type);
13860 Next_Entity (Partial_View);
13863 -- If the partial view was not found then the source code
13864 -- has errors and the derivation is not needed.
13866 if Present (Partial_View) then
13868 First_Elmt (Primitive_Operations (Partial_View));
13869 while Present (Elmt) loop
13870 Ent := Node (Elmt);
13872 if Present (Alias (Ent))
13873 and then Ultimate_Alias (Ent) = Alias (Subp)
13876 (Ent, Primitive_Operations (Derived_Type));
13883 -- If the interface primitive was not found in the
13884 -- partial view then this interface primitive was
13885 -- overridden. We add a derivation to activate in
13886 -- Derive_Progenitor_Subprograms the machinery to
13890 Derive_Interface_Subprogram
13891 (New_Subp => New_Subp,
13893 Actual_Subp => Act_Subp);
13898 Derive_Interface_Subprogram
13899 (New_Subp => New_Subp,
13901 Actual_Subp => Act_Subp);
13904 -- Case 3: Common derivation
13908 (New_Subp => New_Subp,
13909 Parent_Subp => Subp,
13910 Derived_Type => Derived_Type,
13911 Parent_Type => Parent_Base,
13912 Actual_Subp => Act_Subp);
13915 -- No need to update Act_Elm if we must search for the
13916 -- corresponding operation in the generic actual
13919 and then Present (Act_Elmt)
13921 Next_Elmt (Act_Elmt);
13922 Act_Subp := Node (Act_Elmt);
13929 -- Inherit additional operations from progenitors. If the derived
13930 -- type is a generic actual, there are not new primitive operations
13931 -- for the type because it has those of the actual, and therefore
13932 -- nothing needs to be done. The renamings generated above are not
13933 -- primitive operations, and their purpose is simply to make the
13934 -- proper operations visible within an instantiation.
13936 if No (Generic_Actual) then
13937 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
13941 -- Final check: Direct descendants must have their primitives in the
13942 -- same order. We exclude from this test untagged types and instances
13943 -- of formal derived types. We skip this test if we have already
13944 -- reported serious errors in the sources.
13946 pragma Assert (not Is_Tagged_Type (Derived_Type)
13947 or else Present (Generic_Actual)
13948 or else Serious_Errors_Detected > 0
13949 or else Check_Derived_Type);
13950 end Derive_Subprograms;
13952 --------------------------------
13953 -- Derived_Standard_Character --
13954 --------------------------------
13956 procedure Derived_Standard_Character
13958 Parent_Type : Entity_Id;
13959 Derived_Type : Entity_Id)
13961 Loc : constant Source_Ptr := Sloc (N);
13962 Def : constant Node_Id := Type_Definition (N);
13963 Indic : constant Node_Id := Subtype_Indication (Def);
13964 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
13965 Implicit_Base : constant Entity_Id :=
13967 (E_Enumeration_Type, N, Derived_Type, 'B');
13973 Discard_Node (Process_Subtype (Indic, N));
13975 Set_Etype (Implicit_Base, Parent_Base);
13976 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
13977 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
13979 Set_Is_Character_Type (Implicit_Base, True);
13980 Set_Has_Delayed_Freeze (Implicit_Base);
13982 -- The bounds of the implicit base are the bounds of the parent base.
13983 -- Note that their type is the parent base.
13985 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
13986 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
13988 Set_Scalar_Range (Implicit_Base,
13991 High_Bound => Hi));
13993 Conditional_Delay (Derived_Type, Parent_Type);
13995 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
13996 Set_Etype (Derived_Type, Implicit_Base);
13997 Set_Size_Info (Derived_Type, Parent_Type);
13999 if Unknown_RM_Size (Derived_Type) then
14000 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
14003 Set_Is_Character_Type (Derived_Type, True);
14005 if Nkind (Indic) /= N_Subtype_Indication then
14007 -- If no explicit constraint, the bounds are those
14008 -- of the parent type.
14010 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
14011 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
14012 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
14015 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
14017 -- Because the implicit base is used in the conversion of the bounds, we
14018 -- have to freeze it now. This is similar to what is done for numeric
14019 -- types, and it equally suspicious, but otherwise a non-static bound
14020 -- will have a reference to an unfrozen type, which is rejected by Gigi
14021 -- (???). This requires specific care for definition of stream
14022 -- attributes. For details, see comments at the end of
14023 -- Build_Derived_Numeric_Type.
14025 Freeze_Before (N, Implicit_Base);
14026 end Derived_Standard_Character;
14028 ------------------------------
14029 -- Derived_Type_Declaration --
14030 ------------------------------
14032 procedure Derived_Type_Declaration
14035 Is_Completion : Boolean)
14037 Parent_Type : Entity_Id;
14039 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
14040 -- Check whether the parent type is a generic formal, or derives
14041 -- directly or indirectly from one.
14043 ------------------------
14044 -- Comes_From_Generic --
14045 ------------------------
14047 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
14049 if Is_Generic_Type (Typ) then
14052 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
14055 elsif Is_Private_Type (Typ)
14056 and then Present (Full_View (Typ))
14057 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
14061 elsif Is_Generic_Actual_Type (Typ) then
14067 end Comes_From_Generic;
14071 Def : constant Node_Id := Type_Definition (N);
14072 Iface_Def : Node_Id;
14073 Indic : constant Node_Id := Subtype_Indication (Def);
14074 Extension : constant Node_Id := Record_Extension_Part (Def);
14075 Parent_Node : Node_Id;
14078 -- Start of processing for Derived_Type_Declaration
14081 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
14083 -- Ada 2005 (AI-251): In case of interface derivation check that the
14084 -- parent is also an interface.
14086 if Interface_Present (Def) then
14087 Check_SPARK_Restriction ("interface is not allowed", Def);
14089 if not Is_Interface (Parent_Type) then
14090 Diagnose_Interface (Indic, Parent_Type);
14093 Parent_Node := Parent (Base_Type (Parent_Type));
14094 Iface_Def := Type_Definition (Parent_Node);
14096 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
14097 -- other limited interfaces.
14099 if Limited_Present (Def) then
14100 if Limited_Present (Iface_Def) then
14103 elsif Protected_Present (Iface_Def) then
14105 ("descendant of& must be declared"
14106 & " as a protected interface",
14109 elsif Synchronized_Present (Iface_Def) then
14111 ("descendant of& must be declared"
14112 & " as a synchronized interface",
14115 elsif Task_Present (Iface_Def) then
14117 ("descendant of& must be declared as a task interface",
14122 ("(Ada 2005) limited interface cannot "
14123 & "inherit from non-limited interface", Indic);
14126 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
14127 -- from non-limited or limited interfaces.
14129 elsif not Protected_Present (Def)
14130 and then not Synchronized_Present (Def)
14131 and then not Task_Present (Def)
14133 if Limited_Present (Iface_Def) then
14136 elsif Protected_Present (Iface_Def) then
14138 ("descendant of& must be declared"
14139 & " as a protected interface",
14142 elsif Synchronized_Present (Iface_Def) then
14144 ("descendant of& must be declared"
14145 & " as a synchronized interface",
14148 elsif Task_Present (Iface_Def) then
14150 ("descendant of& must be declared as a task interface",
14159 if Is_Tagged_Type (Parent_Type)
14160 and then Is_Concurrent_Type (Parent_Type)
14161 and then not Is_Interface (Parent_Type)
14164 ("parent type of a record extension cannot be "
14165 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
14166 Set_Etype (T, Any_Type);
14170 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
14173 if Is_Tagged_Type (Parent_Type)
14174 and then Is_Non_Empty_List (Interface_List (Def))
14181 Intf := First (Interface_List (Def));
14182 while Present (Intf) loop
14183 T := Find_Type_Of_Subtype_Indic (Intf);
14185 if not Is_Interface (T) then
14186 Diagnose_Interface (Intf, T);
14188 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
14189 -- a limited type from having a nonlimited progenitor.
14191 elsif (Limited_Present (Def)
14192 or else (not Is_Interface (Parent_Type)
14193 and then Is_Limited_Type (Parent_Type)))
14194 and then not Is_Limited_Interface (T)
14197 ("progenitor interface& of limited type must be limited",
14206 if Parent_Type = Any_Type
14207 or else Etype (Parent_Type) = Any_Type
14208 or else (Is_Class_Wide_Type (Parent_Type)
14209 and then Etype (Parent_Type) = T)
14211 -- If Parent_Type is undefined or illegal, make new type into a
14212 -- subtype of Any_Type, and set a few attributes to prevent cascaded
14213 -- errors. If this is a self-definition, emit error now.
14216 or else T = Etype (Parent_Type)
14218 Error_Msg_N ("type cannot be used in its own definition", Indic);
14221 Set_Ekind (T, Ekind (Parent_Type));
14222 Set_Etype (T, Any_Type);
14223 Set_Scalar_Range (T, Scalar_Range (Any_Type));
14225 if Is_Tagged_Type (T)
14226 and then Is_Record_Type (T)
14228 Set_Direct_Primitive_Operations (T, New_Elmt_List);
14234 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
14235 -- an interface is special because the list of interfaces in the full
14236 -- view can be given in any order. For example:
14238 -- type A is interface;
14239 -- type B is interface and A;
14240 -- type D is new B with private;
14242 -- type D is new A and B with null record; -- 1 --
14244 -- In this case we perform the following transformation of -1-:
14246 -- type D is new B and A with null record;
14248 -- If the parent of the full-view covers the parent of the partial-view
14249 -- we have two possible cases:
14251 -- 1) They have the same parent
14252 -- 2) The parent of the full-view implements some further interfaces
14254 -- In both cases we do not need to perform the transformation. In the
14255 -- first case the source program is correct and the transformation is
14256 -- not needed; in the second case the source program does not fulfill
14257 -- the no-hidden interfaces rule (AI-396) and the error will be reported
14260 -- This transformation not only simplifies the rest of the analysis of
14261 -- this type declaration but also simplifies the correct generation of
14262 -- the object layout to the expander.
14264 if In_Private_Part (Current_Scope)
14265 and then Is_Interface (Parent_Type)
14269 Partial_View : Entity_Id;
14270 Partial_View_Parent : Entity_Id;
14271 New_Iface : Node_Id;
14274 -- Look for the associated private type declaration
14276 Partial_View := First_Entity (Current_Scope);
14278 exit when No (Partial_View)
14279 or else (Has_Private_Declaration (Partial_View)
14280 and then Full_View (Partial_View) = T);
14282 Next_Entity (Partial_View);
14285 -- If the partial view was not found then the source code has
14286 -- errors and the transformation is not needed.
14288 if Present (Partial_View) then
14289 Partial_View_Parent := Etype (Partial_View);
14291 -- If the parent of the full-view covers the parent of the
14292 -- partial-view we have nothing else to do.
14294 if Interface_Present_In_Ancestor
14295 (Parent_Type, Partial_View_Parent)
14299 -- Traverse the list of interfaces of the full-view to look
14300 -- for the parent of the partial-view and perform the tree
14304 Iface := First (Interface_List (Def));
14305 while Present (Iface) loop
14306 if Etype (Iface) = Etype (Partial_View) then
14307 Rewrite (Subtype_Indication (Def),
14308 New_Copy (Subtype_Indication
14309 (Parent (Partial_View))));
14312 Make_Identifier (Sloc (N), Chars (Parent_Type));
14313 Append (New_Iface, Interface_List (Def));
14315 -- Analyze the transformed code
14317 Derived_Type_Declaration (T, N, Is_Completion);
14328 -- Only composite types other than array types are allowed to have
14329 -- discriminants. In SPARK, no types are allowed to have discriminants.
14331 if Present (Discriminant_Specifications (N)) then
14332 if (Is_Elementary_Type (Parent_Type)
14333 or else Is_Array_Type (Parent_Type))
14334 and then not Error_Posted (N)
14337 ("elementary or array type cannot have discriminants",
14338 Defining_Identifier (First (Discriminant_Specifications (N))));
14339 Set_Has_Discriminants (T, False);
14341 Check_SPARK_Restriction ("discriminant type is not allowed", N);
14345 -- In Ada 83, a derived type defined in a package specification cannot
14346 -- be used for further derivation until the end of its visible part.
14347 -- Note that derivation in the private part of the package is allowed.
14349 if Ada_Version = Ada_83
14350 and then Is_Derived_Type (Parent_Type)
14351 and then In_Visible_Part (Scope (Parent_Type))
14353 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
14355 ("(Ada 83): premature use of type for derivation", Indic);
14359 -- Check for early use of incomplete or private type
14361 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
14362 Error_Msg_N ("premature derivation of incomplete type", Indic);
14365 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
14366 and then not Comes_From_Generic (Parent_Type))
14367 or else Has_Private_Component (Parent_Type)
14369 -- The ancestor type of a formal type can be incomplete, in which
14370 -- case only the operations of the partial view are available in the
14371 -- generic. Subsequent checks may be required when the full view is
14372 -- analyzed to verify that a derivation from a tagged type has an
14375 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
14378 elsif No (Underlying_Type (Parent_Type))
14379 or else Has_Private_Component (Parent_Type)
14382 ("premature derivation of derived or private type", Indic);
14384 -- Flag the type itself as being in error, this prevents some
14385 -- nasty problems with subsequent uses of the malformed type.
14387 Set_Error_Posted (T);
14389 -- Check that within the immediate scope of an untagged partial
14390 -- view it's illegal to derive from the partial view if the
14391 -- full view is tagged. (7.3(7))
14393 -- We verify that the Parent_Type is a partial view by checking
14394 -- that it is not a Full_Type_Declaration (i.e. a private type or
14395 -- private extension declaration), to distinguish a partial view
14396 -- from a derivation from a private type which also appears as
14397 -- E_Private_Type. If the parent base type is not declared in an
14398 -- enclosing scope there is no need to check.
14400 elsif Present (Full_View (Parent_Type))
14401 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
14402 and then not Is_Tagged_Type (Parent_Type)
14403 and then Is_Tagged_Type (Full_View (Parent_Type))
14404 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
14407 ("premature derivation from type with tagged full view",
14412 -- Check that form of derivation is appropriate
14414 Taggd := Is_Tagged_Type (Parent_Type);
14416 -- Perhaps the parent type should be changed to the class-wide type's
14417 -- specific type in this case to prevent cascading errors ???
14419 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
14420 Error_Msg_N ("parent type must not be a class-wide type", Indic);
14424 if Present (Extension) and then not Taggd then
14426 ("type derived from untagged type cannot have extension", Indic);
14428 elsif No (Extension) and then Taggd then
14430 -- If this declaration is within a private part (or body) of a
14431 -- generic instantiation then the derivation is allowed (the parent
14432 -- type can only appear tagged in this case if it's a generic actual
14433 -- type, since it would otherwise have been rejected in the analysis
14434 -- of the generic template).
14436 if not Is_Generic_Actual_Type (Parent_Type)
14437 or else In_Visible_Part (Scope (Parent_Type))
14439 if Is_Class_Wide_Type (Parent_Type) then
14441 ("parent type must not be a class-wide type", Indic);
14443 -- Use specific type to prevent cascaded errors.
14445 Parent_Type := Etype (Parent_Type);
14449 ("type derived from tagged type must have extension", Indic);
14454 -- AI-443: Synchronized formal derived types require a private
14455 -- extension. There is no point in checking the ancestor type or
14456 -- the progenitors since the construct is wrong to begin with.
14458 if Ada_Version >= Ada_2005
14459 and then Is_Generic_Type (T)
14460 and then Present (Original_Node (N))
14463 Decl : constant Node_Id := Original_Node (N);
14466 if Nkind (Decl) = N_Formal_Type_Declaration
14467 and then Nkind (Formal_Type_Definition (Decl)) =
14468 N_Formal_Derived_Type_Definition
14469 and then Synchronized_Present (Formal_Type_Definition (Decl))
14470 and then No (Extension)
14472 -- Avoid emitting a duplicate error message
14474 and then not Error_Posted (Indic)
14477 ("synchronized derived type must have extension", N);
14482 if Null_Exclusion_Present (Def)
14483 and then not Is_Access_Type (Parent_Type)
14485 Error_Msg_N ("null exclusion can only apply to an access type", N);
14488 -- Avoid deriving parent primitives of underlying record views
14490 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
14491 Derive_Subps => not Is_Underlying_Record_View (T));
14493 -- AI-419: The parent type of an explicitly limited derived type must
14494 -- be a limited type or a limited interface.
14496 if Limited_Present (Def) then
14497 Set_Is_Limited_Record (T);
14499 if Is_Interface (T) then
14500 Set_Is_Limited_Interface (T);
14503 if not Is_Limited_Type (Parent_Type)
14505 (not Is_Interface (Parent_Type)
14506 or else not Is_Limited_Interface (Parent_Type))
14508 -- AI05-0096: a derivation in the private part of an instance is
14509 -- legal if the generic formal is untagged limited, and the actual
14512 if Is_Generic_Actual_Type (Parent_Type)
14513 and then In_Private_Part (Current_Scope)
14516 (Generic_Parent_Type (Parent (Parent_Type)))
14522 ("parent type& of limited type must be limited",
14528 -- In SPARK, there are no derived type definitions other than type
14529 -- extensions of tagged record types.
14531 if No (Extension) then
14532 Check_SPARK_Restriction ("derived type is not allowed", N);
14534 end Derived_Type_Declaration;
14536 ------------------------
14537 -- Diagnose_Interface --
14538 ------------------------
14540 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
14542 if not Is_Interface (E)
14543 and then E /= Any_Type
14545 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
14547 end Diagnose_Interface;
14549 ----------------------------------
14550 -- Enumeration_Type_Declaration --
14551 ----------------------------------
14553 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
14560 -- Create identifier node representing lower bound
14562 B_Node := New_Node (N_Identifier, Sloc (Def));
14563 L := First (Literals (Def));
14564 Set_Chars (B_Node, Chars (L));
14565 Set_Entity (B_Node, L);
14566 Set_Etype (B_Node, T);
14567 Set_Is_Static_Expression (B_Node, True);
14569 R_Node := New_Node (N_Range, Sloc (Def));
14570 Set_Low_Bound (R_Node, B_Node);
14572 Set_Ekind (T, E_Enumeration_Type);
14573 Set_First_Literal (T, L);
14575 Set_Is_Constrained (T);
14579 -- Loop through literals of enumeration type setting pos and rep values
14580 -- except that if the Ekind is already set, then it means the literal
14581 -- was already constructed (case of a derived type declaration and we
14582 -- should not disturb the Pos and Rep values.
14584 while Present (L) loop
14585 if Ekind (L) /= E_Enumeration_Literal then
14586 Set_Ekind (L, E_Enumeration_Literal);
14587 Set_Enumeration_Pos (L, Ev);
14588 Set_Enumeration_Rep (L, Ev);
14589 Set_Is_Known_Valid (L, True);
14593 New_Overloaded_Entity (L);
14594 Generate_Definition (L);
14595 Set_Convention (L, Convention_Intrinsic);
14597 -- Case of character literal
14599 if Nkind (L) = N_Defining_Character_Literal then
14600 Set_Is_Character_Type (T, True);
14602 -- Check violation of No_Wide_Characters
14604 if Restriction_Check_Required (No_Wide_Characters) then
14605 Get_Name_String (Chars (L));
14607 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
14608 Check_Restriction (No_Wide_Characters, L);
14617 -- Now create a node representing upper bound
14619 B_Node := New_Node (N_Identifier, Sloc (Def));
14620 Set_Chars (B_Node, Chars (Last (Literals (Def))));
14621 Set_Entity (B_Node, Last (Literals (Def)));
14622 Set_Etype (B_Node, T);
14623 Set_Is_Static_Expression (B_Node, True);
14625 Set_High_Bound (R_Node, B_Node);
14627 -- Initialize various fields of the type. Some of this information
14628 -- may be overwritten later through rep.clauses.
14630 Set_Scalar_Range (T, R_Node);
14631 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
14632 Set_Enum_Esize (T);
14633 Set_Enum_Pos_To_Rep (T, Empty);
14635 -- Set Discard_Names if configuration pragma set, or if there is
14636 -- a parameterless pragma in the current declarative region
14638 if Global_Discard_Names
14639 or else Discard_Names (Scope (T))
14641 Set_Discard_Names (T);
14644 -- Process end label if there is one
14646 if Present (Def) then
14647 Process_End_Label (Def, 'e', T);
14649 end Enumeration_Type_Declaration;
14651 ---------------------------------
14652 -- Expand_To_Stored_Constraint --
14653 ---------------------------------
14655 function Expand_To_Stored_Constraint
14657 Constraint : Elist_Id) return Elist_Id
14659 Explicitly_Discriminated_Type : Entity_Id;
14660 Expansion : Elist_Id;
14661 Discriminant : Entity_Id;
14663 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
14664 -- Find the nearest type that actually specifies discriminants
14666 ---------------------------------
14667 -- Type_With_Explicit_Discrims --
14668 ---------------------------------
14670 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
14671 Typ : constant E := Base_Type (Id);
14674 if Ekind (Typ) in Incomplete_Or_Private_Kind then
14675 if Present (Full_View (Typ)) then
14676 return Type_With_Explicit_Discrims (Full_View (Typ));
14680 if Has_Discriminants (Typ) then
14685 if Etype (Typ) = Typ then
14687 elsif Has_Discriminants (Typ) then
14690 return Type_With_Explicit_Discrims (Etype (Typ));
14693 end Type_With_Explicit_Discrims;
14695 -- Start of processing for Expand_To_Stored_Constraint
14699 or else Is_Empty_Elmt_List (Constraint)
14704 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
14706 if No (Explicitly_Discriminated_Type) then
14710 Expansion := New_Elmt_List;
14713 First_Stored_Discriminant (Explicitly_Discriminated_Type);
14714 while Present (Discriminant) loop
14716 Get_Discriminant_Value (
14717 Discriminant, Explicitly_Discriminated_Type, Constraint),
14719 Next_Stored_Discriminant (Discriminant);
14723 end Expand_To_Stored_Constraint;
14725 ---------------------------
14726 -- Find_Hidden_Interface --
14727 ---------------------------
14729 function Find_Hidden_Interface
14731 Dest : Elist_Id) return Entity_Id
14734 Iface_Elmt : Elmt_Id;
14737 if Present (Src) and then Present (Dest) then
14738 Iface_Elmt := First_Elmt (Src);
14739 while Present (Iface_Elmt) loop
14740 Iface := Node (Iface_Elmt);
14742 if Is_Interface (Iface)
14743 and then not Contain_Interface (Iface, Dest)
14748 Next_Elmt (Iface_Elmt);
14753 end Find_Hidden_Interface;
14755 --------------------
14756 -- Find_Type_Name --
14757 --------------------
14759 function Find_Type_Name (N : Node_Id) return Entity_Id is
14760 Id : constant Entity_Id := Defining_Identifier (N);
14762 New_Id : Entity_Id;
14763 Prev_Par : Node_Id;
14765 procedure Tag_Mismatch;
14766 -- Diagnose a tagged partial view whose full view is untagged.
14767 -- We post the message on the full view, with a reference to
14768 -- the previous partial view. The partial view can be private
14769 -- or incomplete, and these are handled in a different manner,
14770 -- so we determine the position of the error message from the
14771 -- respective slocs of both.
14777 procedure Tag_Mismatch is
14779 if Sloc (Prev) < Sloc (Id) then
14780 if Ada_Version >= Ada_2012
14781 and then Nkind (N) = N_Private_Type_Declaration
14784 ("declaration of private } must be a tagged type ", Id, Prev);
14787 ("full declaration of } must be a tagged type ", Id, Prev);
14790 if Ada_Version >= Ada_2012
14791 and then Nkind (N) = N_Private_Type_Declaration
14794 ("declaration of private } must be a tagged type ", Prev, Id);
14797 ("full declaration of } must be a tagged type ", Prev, Id);
14802 -- Start of processing for Find_Type_Name
14805 -- Find incomplete declaration, if one was given
14807 Prev := Current_Entity_In_Scope (Id);
14809 -- New type declaration
14815 -- Previous declaration exists
14818 Prev_Par := Parent (Prev);
14820 -- Error if not incomplete/private case except if previous
14821 -- declaration is implicit, etc. Enter_Name will emit error if
14824 if not Is_Incomplete_Or_Private_Type (Prev) then
14828 -- Check invalid completion of private or incomplete type
14830 elsif not Nkind_In (N, N_Full_Type_Declaration,
14831 N_Task_Type_Declaration,
14832 N_Protected_Type_Declaration)
14834 (Ada_Version < Ada_2012
14835 or else not Is_Incomplete_Type (Prev)
14836 or else not Nkind_In (N, N_Private_Type_Declaration,
14837 N_Private_Extension_Declaration))
14839 -- Completion must be a full type declarations (RM 7.3(4))
14841 Error_Msg_Sloc := Sloc (Prev);
14842 Error_Msg_NE ("invalid completion of }", Id, Prev);
14844 -- Set scope of Id to avoid cascaded errors. Entity is never
14845 -- examined again, except when saving globals in generics.
14847 Set_Scope (Id, Current_Scope);
14850 -- If this is a repeated incomplete declaration, no further
14851 -- checks are possible.
14853 if Nkind (N) = N_Incomplete_Type_Declaration then
14857 -- Case of full declaration of incomplete type
14859 elsif Ekind (Prev) = E_Incomplete_Type
14860 and then (Ada_Version < Ada_2012
14861 or else No (Full_View (Prev))
14862 or else not Is_Private_Type (Full_View (Prev)))
14865 -- Indicate that the incomplete declaration has a matching full
14866 -- declaration. The defining occurrence of the incomplete
14867 -- declaration remains the visible one, and the procedure
14868 -- Get_Full_View dereferences it whenever the type is used.
14870 if Present (Full_View (Prev)) then
14871 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
14874 Set_Full_View (Prev, Id);
14875 Append_Entity (Id, Current_Scope);
14876 Set_Is_Public (Id, Is_Public (Prev));
14877 Set_Is_Internal (Id);
14880 -- If the incomplete view is tagged, a class_wide type has been
14881 -- created already. Use it for the private type as well, in order
14882 -- to prevent multiple incompatible class-wide types that may be
14883 -- created for self-referential anonymous access components.
14885 if Is_Tagged_Type (Prev)
14886 and then Present (Class_Wide_Type (Prev))
14888 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
14889 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
14890 Set_Etype (Class_Wide_Type (Id), Id);
14893 -- Case of full declaration of private type
14896 -- If the private type was a completion of an incomplete type then
14897 -- update Prev to reference the private type
14899 if Ada_Version >= Ada_2012
14900 and then Ekind (Prev) = E_Incomplete_Type
14901 and then Present (Full_View (Prev))
14902 and then Is_Private_Type (Full_View (Prev))
14904 Prev := Full_View (Prev);
14905 Prev_Par := Parent (Prev);
14908 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
14909 if Etype (Prev) /= Prev then
14911 -- Prev is a private subtype or a derived type, and needs
14914 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
14917 elsif Ekind (Prev) = E_Private_Type
14918 and then Nkind_In (N, N_Task_Type_Declaration,
14919 N_Protected_Type_Declaration)
14922 ("completion of nonlimited type cannot be limited", N);
14924 elsif Ekind (Prev) = E_Record_Type_With_Private
14925 and then Nkind_In (N, N_Task_Type_Declaration,
14926 N_Protected_Type_Declaration)
14928 if not Is_Limited_Record (Prev) then
14930 ("completion of nonlimited type cannot be limited", N);
14932 elsif No (Interface_List (N)) then
14934 ("completion of tagged private type must be tagged",
14938 elsif Nkind (N) = N_Full_Type_Declaration
14940 Nkind (Type_Definition (N)) = N_Record_Definition
14941 and then Interface_Present (Type_Definition (N))
14944 ("completion of private type cannot be an interface", N);
14947 -- Ada 2005 (AI-251): Private extension declaration of a task
14948 -- type or a protected type. This case arises when covering
14949 -- interface types.
14951 elsif Nkind_In (N, N_Task_Type_Declaration,
14952 N_Protected_Type_Declaration)
14956 elsif Nkind (N) /= N_Full_Type_Declaration
14957 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
14960 ("full view of private extension must be an extension", N);
14962 elsif not (Abstract_Present (Parent (Prev)))
14963 and then Abstract_Present (Type_Definition (N))
14966 ("full view of non-abstract extension cannot be abstract", N);
14969 if not In_Private_Part (Current_Scope) then
14971 ("declaration of full view must appear in private part", N);
14974 Copy_And_Swap (Prev, Id);
14975 Set_Has_Private_Declaration (Prev);
14976 Set_Has_Private_Declaration (Id);
14978 -- Preserve aspect and iterator flags that may have been set on
14979 -- the partial view.
14981 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
14982 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
14984 -- If no error, propagate freeze_node from private to full view.
14985 -- It may have been generated for an early operational item.
14987 if Present (Freeze_Node (Id))
14988 and then Serious_Errors_Detected = 0
14989 and then No (Full_View (Id))
14991 Set_Freeze_Node (Prev, Freeze_Node (Id));
14992 Set_Freeze_Node (Id, Empty);
14993 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
14996 Set_Full_View (Id, Prev);
15000 -- Verify that full declaration conforms to partial one
15002 if Is_Incomplete_Or_Private_Type (Prev)
15003 and then Present (Discriminant_Specifications (Prev_Par))
15005 if Present (Discriminant_Specifications (N)) then
15006 if Ekind (Prev) = E_Incomplete_Type then
15007 Check_Discriminant_Conformance (N, Prev, Prev);
15009 Check_Discriminant_Conformance (N, Prev, Id);
15014 ("missing discriminants in full type declaration", N);
15016 -- To avoid cascaded errors on subsequent use, share the
15017 -- discriminants of the partial view.
15019 Set_Discriminant_Specifications (N,
15020 Discriminant_Specifications (Prev_Par));
15024 -- A prior untagged partial view can have an associated class-wide
15025 -- type due to use of the class attribute, and in this case the full
15026 -- type must also be tagged. This Ada 95 usage is deprecated in favor
15027 -- of incomplete tagged declarations, but we check for it.
15030 and then (Is_Tagged_Type (Prev)
15031 or else Present (Class_Wide_Type (Prev)))
15033 -- Ada 2012 (AI05-0162): A private type may be the completion of
15034 -- an incomplete type
15036 if Ada_Version >= Ada_2012
15037 and then Is_Incomplete_Type (Prev)
15038 and then Nkind_In (N, N_Private_Type_Declaration,
15039 N_Private_Extension_Declaration)
15041 -- No need to check private extensions since they are tagged
15043 if Nkind (N) = N_Private_Type_Declaration
15044 and then not Tagged_Present (N)
15049 -- The full declaration is either a tagged type (including
15050 -- a synchronized type that implements interfaces) or a
15051 -- type extension, otherwise this is an error.
15053 elsif Nkind_In (N, N_Task_Type_Declaration,
15054 N_Protected_Type_Declaration)
15056 if No (Interface_List (N))
15057 and then not Error_Posted (N)
15062 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
15064 -- Indicate that the previous declaration (tagged incomplete
15065 -- or private declaration) requires the same on the full one.
15067 if not Tagged_Present (Type_Definition (N)) then
15069 Set_Is_Tagged_Type (Id);
15072 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
15073 if No (Record_Extension_Part (Type_Definition (N))) then
15075 ("full declaration of } must be a record extension",
15078 -- Set some attributes to produce a usable full view
15080 Set_Is_Tagged_Type (Id);
15089 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
15090 and then Present (Premature_Use (Parent (Prev)))
15092 Error_Msg_Sloc := Sloc (N);
15094 ("\full declaration #", Premature_Use (Parent (Prev)));
15099 end Find_Type_Name;
15101 -------------------------
15102 -- Find_Type_Of_Object --
15103 -------------------------
15105 function Find_Type_Of_Object
15106 (Obj_Def : Node_Id;
15107 Related_Nod : Node_Id) return Entity_Id
15109 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
15110 P : Node_Id := Parent (Obj_Def);
15115 -- If the parent is a component_definition node we climb to the
15116 -- component_declaration node
15118 if Nkind (P) = N_Component_Definition then
15122 -- Case of an anonymous array subtype
15124 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
15125 N_Unconstrained_Array_Definition)
15128 Array_Type_Declaration (T, Obj_Def);
15130 -- Create an explicit subtype whenever possible
15132 elsif Nkind (P) /= N_Component_Declaration
15133 and then Def_Kind = N_Subtype_Indication
15135 -- Base name of subtype on object name, which will be unique in
15136 -- the current scope.
15138 -- If this is a duplicate declaration, return base type, to avoid
15139 -- generating duplicate anonymous types.
15141 if Error_Posted (P) then
15142 Analyze (Subtype_Mark (Obj_Def));
15143 return Entity (Subtype_Mark (Obj_Def));
15148 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
15150 T := Make_Defining_Identifier (Sloc (P), Nam);
15152 Insert_Action (Obj_Def,
15153 Make_Subtype_Declaration (Sloc (P),
15154 Defining_Identifier => T,
15155 Subtype_Indication => Relocate_Node (Obj_Def)));
15157 -- This subtype may need freezing, and this will not be done
15158 -- automatically if the object declaration is not in declarative
15159 -- part. Since this is an object declaration, the type cannot always
15160 -- be frozen here. Deferred constants do not freeze their type
15161 -- (which often enough will be private).
15163 if Nkind (P) = N_Object_Declaration
15164 and then Constant_Present (P)
15165 and then No (Expression (P))
15169 Insert_Actions (Obj_Def, Freeze_Entity (T, P));
15172 -- Ada 2005 AI-406: the object definition in an object declaration
15173 -- can be an access definition.
15175 elsif Def_Kind = N_Access_Definition then
15176 T := Access_Definition (Related_Nod, Obj_Def);
15178 Set_Is_Local_Anonymous_Access
15180 V => (Ada_Version < Ada_2012)
15181 or else (Nkind (P) /= N_Object_Declaration)
15182 or else Is_Library_Level_Entity (Defining_Identifier (P)));
15184 -- Otherwise, the object definition is just a subtype_mark
15187 T := Process_Subtype (Obj_Def, Related_Nod);
15189 -- If expansion is disabled an object definition that is an aggregate
15190 -- will not get expanded and may lead to scoping problems in the back
15191 -- end, if the object is referenced in an inner scope. In that case
15192 -- create an itype reference for the object definition now. This
15193 -- may be redundant in some cases, but harmless.
15196 and then Nkind (Related_Nod) = N_Object_Declaration
15199 Build_Itype_Reference (T, Related_Nod);
15204 end Find_Type_Of_Object;
15206 --------------------------------
15207 -- Find_Type_Of_Subtype_Indic --
15208 --------------------------------
15210 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
15214 -- Case of subtype mark with a constraint
15216 if Nkind (S) = N_Subtype_Indication then
15217 Find_Type (Subtype_Mark (S));
15218 Typ := Entity (Subtype_Mark (S));
15221 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
15224 ("incorrect constraint for this kind of type", Constraint (S));
15225 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
15228 -- Otherwise we have a subtype mark without a constraint
15230 elsif Error_Posted (S) then
15231 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
15239 -- Check No_Wide_Characters restriction
15241 Check_Wide_Character_Restriction (Typ, S);
15244 end Find_Type_Of_Subtype_Indic;
15246 -------------------------------------
15247 -- Floating_Point_Type_Declaration --
15248 -------------------------------------
15250 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
15251 Digs : constant Node_Id := Digits_Expression (Def);
15252 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
15254 Base_Typ : Entity_Id;
15255 Implicit_Base : Entity_Id;
15258 function Can_Derive_From (E : Entity_Id) return Boolean;
15259 -- Find if given digits value, and possibly a specified range, allows
15260 -- derivation from specified type
15262 function Find_Base_Type return Entity_Id;
15263 -- Find a predefined base type that Def can derive from, or generate
15264 -- an error and substitute Long_Long_Float if none exists.
15266 ---------------------
15267 -- Can_Derive_From --
15268 ---------------------
15270 function Can_Derive_From (E : Entity_Id) return Boolean is
15271 Spec : constant Entity_Id := Real_Range_Specification (Def);
15274 if Digs_Val > Digits_Value (E) then
15278 if Present (Spec) then
15279 if Expr_Value_R (Type_Low_Bound (E)) >
15280 Expr_Value_R (Low_Bound (Spec))
15285 if Expr_Value_R (Type_High_Bound (E)) <
15286 Expr_Value_R (High_Bound (Spec))
15293 end Can_Derive_From;
15295 --------------------
15296 -- Find_Base_Type --
15297 --------------------
15299 function Find_Base_Type return Entity_Id is
15300 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
15303 -- Iterate over the predefined types in order, returning the first
15304 -- one that Def can derive from.
15306 while Present (Choice) loop
15307 if Can_Derive_From (Node (Choice)) then
15308 return Node (Choice);
15311 Next_Elmt (Choice);
15314 -- If we can't derive from any existing type, use Long_Long_Float
15315 -- and give appropriate message explaining the problem.
15317 if Digs_Val > Max_Digs_Val then
15318 -- It might be the case that there is a type with the requested
15319 -- range, just not the combination of digits and range.
15322 ("no predefined type has requested range and precision",
15323 Real_Range_Specification (Def));
15327 ("range too large for any predefined type",
15328 Real_Range_Specification (Def));
15331 return Standard_Long_Long_Float;
15332 end Find_Base_Type;
15334 -- Start of processing for Floating_Point_Type_Declaration
15337 Check_Restriction (No_Floating_Point, Def);
15339 -- Create an implicit base type
15342 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
15344 -- Analyze and verify digits value
15346 Analyze_And_Resolve (Digs, Any_Integer);
15347 Check_Digits_Expression (Digs);
15348 Digs_Val := Expr_Value (Digs);
15350 -- Process possible range spec and find correct type to derive from
15352 Process_Real_Range_Specification (Def);
15354 -- Check that requested number of digits is not too high.
15356 if Digs_Val > Max_Digs_Val then
15357 -- The check for Max_Base_Digits may be somewhat expensive, as it
15358 -- requires reading System, so only do it when necessary.
15361 Max_Base_Digits : constant Uint :=
15364 (Parent (RTE (RE_Max_Base_Digits))));
15367 if Digs_Val > Max_Base_Digits then
15368 Error_Msg_Uint_1 := Max_Base_Digits;
15369 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
15371 elsif No (Real_Range_Specification (Def)) then
15372 Error_Msg_Uint_1 := Max_Digs_Val;
15373 Error_Msg_N ("types with more than ^ digits need range spec "
15374 & "(RM 3.5.7(6))", Digs);
15379 -- Find a suitable type to derive from or complain and use a substitute
15381 Base_Typ := Find_Base_Type;
15383 -- If there are bounds given in the declaration use them as the bounds
15384 -- of the type, otherwise use the bounds of the predefined base type
15385 -- that was chosen based on the Digits value.
15387 if Present (Real_Range_Specification (Def)) then
15388 Set_Scalar_Range (T, Real_Range_Specification (Def));
15389 Set_Is_Constrained (T);
15391 -- The bounds of this range must be converted to machine numbers
15392 -- in accordance with RM 4.9(38).
15394 Bound := Type_Low_Bound (T);
15396 if Nkind (Bound) = N_Real_Literal then
15398 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
15399 Set_Is_Machine_Number (Bound);
15402 Bound := Type_High_Bound (T);
15404 if Nkind (Bound) = N_Real_Literal then
15406 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
15407 Set_Is_Machine_Number (Bound);
15411 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
15414 -- Complete definition of implicit base and declared first subtype
15416 Set_Etype (Implicit_Base, Base_Typ);
15418 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
15419 Set_Size_Info (Implicit_Base, (Base_Typ));
15420 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
15421 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
15422 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
15423 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
15425 Set_Ekind (T, E_Floating_Point_Subtype);
15426 Set_Etype (T, Implicit_Base);
15428 Set_Size_Info (T, (Implicit_Base));
15429 Set_RM_Size (T, RM_Size (Implicit_Base));
15430 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
15431 Set_Digits_Value (T, Digs_Val);
15432 end Floating_Point_Type_Declaration;
15434 ----------------------------
15435 -- Get_Discriminant_Value --
15436 ----------------------------
15438 -- This is the situation:
15440 -- There is a non-derived type
15442 -- type T0 (Dx, Dy, Dz...)
15444 -- There are zero or more levels of derivation, with each derivation
15445 -- either purely inheriting the discriminants, or defining its own.
15447 -- type Ti is new Ti-1
15449 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
15451 -- subtype Ti is ...
15453 -- The subtype issue is avoided by the use of Original_Record_Component,
15454 -- and the fact that derived subtypes also derive the constraints.
15456 -- This chain leads back from
15458 -- Typ_For_Constraint
15460 -- Typ_For_Constraint has discriminants, and the value for each
15461 -- discriminant is given by its corresponding Elmt of Constraints.
15463 -- Discriminant is some discriminant in this hierarchy
15465 -- We need to return its value
15467 -- We do this by recursively searching each level, and looking for
15468 -- Discriminant. Once we get to the bottom, we start backing up
15469 -- returning the value for it which may in turn be a discriminant
15470 -- further up, so on the backup we continue the substitution.
15472 function Get_Discriminant_Value
15473 (Discriminant : Entity_Id;
15474 Typ_For_Constraint : Entity_Id;
15475 Constraint : Elist_Id) return Node_Id
15477 function Search_Derivation_Levels
15479 Discrim_Values : Elist_Id;
15480 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
15481 -- This is the routine that performs the recursive search of levels
15482 -- as described above.
15484 ------------------------------
15485 -- Search_Derivation_Levels --
15486 ------------------------------
15488 function Search_Derivation_Levels
15490 Discrim_Values : Elist_Id;
15491 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
15495 Result : Node_Or_Entity_Id;
15496 Result_Entity : Node_Id;
15499 -- If inappropriate type, return Error, this happens only in
15500 -- cascaded error situations, and we want to avoid a blow up.
15502 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
15506 -- Look deeper if possible. Use Stored_Constraints only for
15507 -- untagged types. For tagged types use the given constraint.
15508 -- This asymmetry needs explanation???
15510 if not Stored_Discrim_Values
15511 and then Present (Stored_Constraint (Ti))
15512 and then not Is_Tagged_Type (Ti)
15515 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
15518 Td : constant Entity_Id := Etype (Ti);
15522 Result := Discriminant;
15525 if Present (Stored_Constraint (Ti)) then
15527 Search_Derivation_Levels
15528 (Td, Stored_Constraint (Ti), True);
15531 Search_Derivation_Levels
15532 (Td, Discrim_Values, Stored_Discrim_Values);
15538 -- Extra underlying places to search, if not found above. For
15539 -- concurrent types, the relevant discriminant appears in the
15540 -- corresponding record. For a type derived from a private type
15541 -- without discriminant, the full view inherits the discriminants
15542 -- of the full view of the parent.
15544 if Result = Discriminant then
15545 if Is_Concurrent_Type (Ti)
15546 and then Present (Corresponding_Record_Type (Ti))
15549 Search_Derivation_Levels (
15550 Corresponding_Record_Type (Ti),
15552 Stored_Discrim_Values);
15554 elsif Is_Private_Type (Ti)
15555 and then not Has_Discriminants (Ti)
15556 and then Present (Full_View (Ti))
15557 and then Etype (Full_View (Ti)) /= Ti
15560 Search_Derivation_Levels (
15563 Stored_Discrim_Values);
15567 -- If Result is not a (reference to a) discriminant, return it,
15568 -- otherwise set Result_Entity to the discriminant.
15570 if Nkind (Result) = N_Defining_Identifier then
15571 pragma Assert (Result = Discriminant);
15572 Result_Entity := Result;
15575 if not Denotes_Discriminant (Result) then
15579 Result_Entity := Entity (Result);
15582 -- See if this level of derivation actually has discriminants
15583 -- because tagged derivations can add them, hence the lower
15584 -- levels need not have any.
15586 if not Has_Discriminants (Ti) then
15590 -- Scan Ti's discriminants for Result_Entity,
15591 -- and return its corresponding value, if any.
15593 Result_Entity := Original_Record_Component (Result_Entity);
15595 Assoc := First_Elmt (Discrim_Values);
15597 if Stored_Discrim_Values then
15598 Disc := First_Stored_Discriminant (Ti);
15600 Disc := First_Discriminant (Ti);
15603 while Present (Disc) loop
15604 pragma Assert (Present (Assoc));
15606 if Original_Record_Component (Disc) = Result_Entity then
15607 return Node (Assoc);
15612 if Stored_Discrim_Values then
15613 Next_Stored_Discriminant (Disc);
15615 Next_Discriminant (Disc);
15619 -- Could not find it
15622 end Search_Derivation_Levels;
15626 Result : Node_Or_Entity_Id;
15628 -- Start of processing for Get_Discriminant_Value
15631 -- ??? This routine is a gigantic mess and will be deleted. For the
15632 -- time being just test for the trivial case before calling recurse.
15634 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
15640 D := First_Discriminant (Typ_For_Constraint);
15641 E := First_Elmt (Constraint);
15642 while Present (D) loop
15643 if Chars (D) = Chars (Discriminant) then
15647 Next_Discriminant (D);
15653 Result := Search_Derivation_Levels
15654 (Typ_For_Constraint, Constraint, False);
15656 -- ??? hack to disappear when this routine is gone
15658 if Nkind (Result) = N_Defining_Identifier then
15664 D := First_Discriminant (Typ_For_Constraint);
15665 E := First_Elmt (Constraint);
15666 while Present (D) loop
15667 if Corresponding_Discriminant (D) = Discriminant then
15671 Next_Discriminant (D);
15677 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
15679 end Get_Discriminant_Value;
15681 --------------------------
15682 -- Has_Range_Constraint --
15683 --------------------------
15685 function Has_Range_Constraint (N : Node_Id) return Boolean is
15686 C : constant Node_Id := Constraint (N);
15689 if Nkind (C) = N_Range_Constraint then
15692 elsif Nkind (C) = N_Digits_Constraint then
15694 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
15696 Present (Range_Constraint (C));
15698 elsif Nkind (C) = N_Delta_Constraint then
15699 return Present (Range_Constraint (C));
15704 end Has_Range_Constraint;
15706 ------------------------
15707 -- Inherit_Components --
15708 ------------------------
15710 function Inherit_Components
15712 Parent_Base : Entity_Id;
15713 Derived_Base : Entity_Id;
15714 Is_Tagged : Boolean;
15715 Inherit_Discr : Boolean;
15716 Discs : Elist_Id) return Elist_Id
15718 Assoc_List : constant Elist_Id := New_Elmt_List;
15720 procedure Inherit_Component
15721 (Old_C : Entity_Id;
15722 Plain_Discrim : Boolean := False;
15723 Stored_Discrim : Boolean := False);
15724 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
15725 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
15726 -- True, Old_C is a stored discriminant. If they are both false then
15727 -- Old_C is a regular component.
15729 -----------------------
15730 -- Inherit_Component --
15731 -----------------------
15733 procedure Inherit_Component
15734 (Old_C : Entity_Id;
15735 Plain_Discrim : Boolean := False;
15736 Stored_Discrim : Boolean := False)
15738 procedure Set_Anonymous_Type (Id : Entity_Id);
15739 -- Id denotes the entity of an access discriminant or anonymous
15740 -- access component. Set the type of Id to either the same type of
15741 -- Old_C or create a new one depending on whether the parent and
15742 -- the child types are in the same scope.
15744 ------------------------
15745 -- Set_Anonymous_Type --
15746 ------------------------
15748 procedure Set_Anonymous_Type (Id : Entity_Id) is
15749 Old_Typ : constant Entity_Id := Etype (Old_C);
15752 if Scope (Parent_Base) = Scope (Derived_Base) then
15753 Set_Etype (Id, Old_Typ);
15755 -- The parent and the derived type are in two different scopes.
15756 -- Reuse the type of the original discriminant / component by
15757 -- copying it in order to preserve all attributes.
15761 Typ : constant Entity_Id := New_Copy (Old_Typ);
15764 Set_Etype (Id, Typ);
15766 -- Since we do not generate component declarations for
15767 -- inherited components, associate the itype with the
15770 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
15771 Set_Scope (Typ, Derived_Base);
15774 end Set_Anonymous_Type;
15776 -- Local variables and constants
15778 New_C : constant Entity_Id := New_Copy (Old_C);
15780 Corr_Discrim : Entity_Id;
15781 Discrim : Entity_Id;
15783 -- Start of processing for Inherit_Component
15786 pragma Assert (not Is_Tagged or else not Stored_Discrim);
15788 Set_Parent (New_C, Parent (Old_C));
15790 -- Regular discriminants and components must be inserted in the scope
15791 -- of the Derived_Base. Do it here.
15793 if not Stored_Discrim then
15794 Enter_Name (New_C);
15797 -- For tagged types the Original_Record_Component must point to
15798 -- whatever this field was pointing to in the parent type. This has
15799 -- already been achieved by the call to New_Copy above.
15801 if not Is_Tagged then
15802 Set_Original_Record_Component (New_C, New_C);
15805 -- Set the proper type of an access discriminant
15807 if Ekind (New_C) = E_Discriminant
15808 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
15810 Set_Anonymous_Type (New_C);
15813 -- If we have inherited a component then see if its Etype contains
15814 -- references to Parent_Base discriminants. In this case, replace
15815 -- these references with the constraints given in Discs. We do not
15816 -- do this for the partial view of private types because this is
15817 -- not needed (only the components of the full view will be used
15818 -- for code generation) and cause problem. We also avoid this
15819 -- transformation in some error situations.
15821 if Ekind (New_C) = E_Component then
15823 -- Set the proper type of an anonymous access component
15825 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
15826 Set_Anonymous_Type (New_C);
15828 elsif (Is_Private_Type (Derived_Base)
15829 and then not Is_Generic_Type (Derived_Base))
15830 or else (Is_Empty_Elmt_List (Discs)
15831 and then not Expander_Active)
15833 Set_Etype (New_C, Etype (Old_C));
15836 -- The current component introduces a circularity of the
15839 -- limited with Pack_2;
15840 -- package Pack_1 is
15841 -- type T_1 is tagged record
15842 -- Comp : access Pack_2.T_2;
15848 -- package Pack_2 is
15849 -- type T_2 is new Pack_1.T_1 with ...;
15854 Constrain_Component_Type
15855 (Old_C, Derived_Base, N, Parent_Base, Discs));
15859 -- In derived tagged types it is illegal to reference a non
15860 -- discriminant component in the parent type. To catch this, mark
15861 -- these components with an Ekind of E_Void. This will be reset in
15862 -- Record_Type_Definition after processing the record extension of
15863 -- the derived type.
15865 -- If the declaration is a private extension, there is no further
15866 -- record extension to process, and the components retain their
15867 -- current kind, because they are visible at this point.
15869 if Is_Tagged and then Ekind (New_C) = E_Component
15870 and then Nkind (N) /= N_Private_Extension_Declaration
15872 Set_Ekind (New_C, E_Void);
15875 if Plain_Discrim then
15876 Set_Corresponding_Discriminant (New_C, Old_C);
15877 Build_Discriminal (New_C);
15879 -- If we are explicitly inheriting a stored discriminant it will be
15880 -- completely hidden.
15882 elsif Stored_Discrim then
15883 Set_Corresponding_Discriminant (New_C, Empty);
15884 Set_Discriminal (New_C, Empty);
15885 Set_Is_Completely_Hidden (New_C);
15887 -- Set the Original_Record_Component of each discriminant in the
15888 -- derived base to point to the corresponding stored that we just
15891 Discrim := First_Discriminant (Derived_Base);
15892 while Present (Discrim) loop
15893 Corr_Discrim := Corresponding_Discriminant (Discrim);
15895 -- Corr_Discrim could be missing in an error situation
15897 if Present (Corr_Discrim)
15898 and then Original_Record_Component (Corr_Discrim) = Old_C
15900 Set_Original_Record_Component (Discrim, New_C);
15903 Next_Discriminant (Discrim);
15906 Append_Entity (New_C, Derived_Base);
15909 if not Is_Tagged then
15910 Append_Elmt (Old_C, Assoc_List);
15911 Append_Elmt (New_C, Assoc_List);
15913 end Inherit_Component;
15915 -- Variables local to Inherit_Component
15917 Loc : constant Source_Ptr := Sloc (N);
15919 Parent_Discrim : Entity_Id;
15920 Stored_Discrim : Entity_Id;
15922 Component : Entity_Id;
15924 -- Start of processing for Inherit_Components
15927 if not Is_Tagged then
15928 Append_Elmt (Parent_Base, Assoc_List);
15929 Append_Elmt (Derived_Base, Assoc_List);
15932 -- Inherit parent discriminants if needed
15934 if Inherit_Discr then
15935 Parent_Discrim := First_Discriminant (Parent_Base);
15936 while Present (Parent_Discrim) loop
15937 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
15938 Next_Discriminant (Parent_Discrim);
15942 -- Create explicit stored discrims for untagged types when necessary
15944 if not Has_Unknown_Discriminants (Derived_Base)
15945 and then Has_Discriminants (Parent_Base)
15946 and then not Is_Tagged
15949 or else First_Discriminant (Parent_Base) /=
15950 First_Stored_Discriminant (Parent_Base))
15952 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
15953 while Present (Stored_Discrim) loop
15954 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
15955 Next_Stored_Discriminant (Stored_Discrim);
15959 -- See if we can apply the second transformation for derived types, as
15960 -- explained in point 6. in the comments above Build_Derived_Record_Type
15961 -- This is achieved by appending Derived_Base discriminants into Discs,
15962 -- which has the side effect of returning a non empty Discs list to the
15963 -- caller of Inherit_Components, which is what we want. This must be
15964 -- done for private derived types if there are explicit stored
15965 -- discriminants, to ensure that we can retrieve the values of the
15966 -- constraints provided in the ancestors.
15969 and then Is_Empty_Elmt_List (Discs)
15970 and then Present (First_Discriminant (Derived_Base))
15972 (not Is_Private_Type (Derived_Base)
15973 or else Is_Completely_Hidden
15974 (First_Stored_Discriminant (Derived_Base))
15975 or else Is_Generic_Type (Derived_Base))
15977 D := First_Discriminant (Derived_Base);
15978 while Present (D) loop
15979 Append_Elmt (New_Reference_To (D, Loc), Discs);
15980 Next_Discriminant (D);
15984 -- Finally, inherit non-discriminant components unless they are not
15985 -- visible because defined or inherited from the full view of the
15986 -- parent. Don't inherit the _parent field of the parent type.
15988 Component := First_Entity (Parent_Base);
15989 while Present (Component) loop
15991 -- Ada 2005 (AI-251): Do not inherit components associated with
15992 -- secondary tags of the parent.
15994 if Ekind (Component) = E_Component
15995 and then Present (Related_Type (Component))
15999 elsif Ekind (Component) /= E_Component
16000 or else Chars (Component) = Name_uParent
16004 -- If the derived type is within the parent type's declarative
16005 -- region, then the components can still be inherited even though
16006 -- they aren't visible at this point. This can occur for cases
16007 -- such as within public child units where the components must
16008 -- become visible upon entering the child unit's private part.
16010 elsif not Is_Visible_Component (Component)
16011 and then not In_Open_Scopes (Scope (Parent_Base))
16015 elsif Ekind_In (Derived_Base, E_Private_Type,
16016 E_Limited_Private_Type)
16021 Inherit_Component (Component);
16024 Next_Entity (Component);
16027 -- For tagged derived types, inherited discriminants cannot be used in
16028 -- component declarations of the record extension part. To achieve this
16029 -- we mark the inherited discriminants as not visible.
16031 if Is_Tagged and then Inherit_Discr then
16032 D := First_Discriminant (Derived_Base);
16033 while Present (D) loop
16034 Set_Is_Immediately_Visible (D, False);
16035 Next_Discriminant (D);
16040 end Inherit_Components;
16042 -----------------------
16043 -- Is_Constant_Bound --
16044 -----------------------
16046 function Is_Constant_Bound (Exp : Node_Id) return Boolean is
16048 if Compile_Time_Known_Value (Exp) then
16051 elsif Is_Entity_Name (Exp)
16052 and then Present (Entity (Exp))
16054 return Is_Constant_Object (Entity (Exp))
16055 or else Ekind (Entity (Exp)) = E_Enumeration_Literal;
16057 elsif Nkind (Exp) in N_Binary_Op then
16058 return Is_Constant_Bound (Left_Opnd (Exp))
16059 and then Is_Constant_Bound (Right_Opnd (Exp))
16060 and then Scope (Entity (Exp)) = Standard_Standard;
16065 end Is_Constant_Bound;
16067 -----------------------
16068 -- Is_Null_Extension --
16069 -----------------------
16071 function Is_Null_Extension (T : Entity_Id) return Boolean is
16072 Type_Decl : constant Node_Id := Parent (Base_Type (T));
16073 Comp_List : Node_Id;
16077 if Nkind (Type_Decl) /= N_Full_Type_Declaration
16078 or else not Is_Tagged_Type (T)
16079 or else Nkind (Type_Definition (Type_Decl)) /=
16080 N_Derived_Type_Definition
16081 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
16087 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
16089 if Present (Discriminant_Specifications (Type_Decl)) then
16092 elsif Present (Comp_List)
16093 and then Is_Non_Empty_List (Component_Items (Comp_List))
16095 Comp := First (Component_Items (Comp_List));
16097 -- Only user-defined components are relevant. The component list
16098 -- may also contain a parent component and internal components
16099 -- corresponding to secondary tags, but these do not determine
16100 -- whether this is a null extension.
16102 while Present (Comp) loop
16103 if Comes_From_Source (Comp) then
16114 end Is_Null_Extension;
16116 ------------------------------
16117 -- Is_Valid_Constraint_Kind --
16118 ------------------------------
16120 function Is_Valid_Constraint_Kind
16121 (T_Kind : Type_Kind;
16122 Constraint_Kind : Node_Kind) return Boolean
16126 when Enumeration_Kind |
16128 return Constraint_Kind = N_Range_Constraint;
16130 when Decimal_Fixed_Point_Kind =>
16131 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
16132 N_Range_Constraint);
16134 when Ordinary_Fixed_Point_Kind =>
16135 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
16136 N_Range_Constraint);
16139 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
16140 N_Range_Constraint);
16147 E_Incomplete_Type |
16150 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
16153 return True; -- Error will be detected later
16155 end Is_Valid_Constraint_Kind;
16157 --------------------------
16158 -- Is_Visible_Component --
16159 --------------------------
16161 function Is_Visible_Component (C : Entity_Id) return Boolean is
16162 Original_Comp : Entity_Id := Empty;
16163 Original_Scope : Entity_Id;
16164 Type_Scope : Entity_Id;
16166 function Is_Local_Type (Typ : Entity_Id) return Boolean;
16167 -- Check whether parent type of inherited component is declared locally,
16168 -- possibly within a nested package or instance. The current scope is
16169 -- the derived record itself.
16171 -------------------
16172 -- Is_Local_Type --
16173 -------------------
16175 function Is_Local_Type (Typ : Entity_Id) return Boolean is
16179 Scop := Scope (Typ);
16180 while Present (Scop)
16181 and then Scop /= Standard_Standard
16183 if Scop = Scope (Current_Scope) then
16187 Scop := Scope (Scop);
16193 -- Start of processing for Is_Visible_Component
16196 if Ekind_In (C, E_Component, E_Discriminant) then
16197 Original_Comp := Original_Record_Component (C);
16200 if No (Original_Comp) then
16202 -- Premature usage, or previous error
16207 Original_Scope := Scope (Original_Comp);
16208 Type_Scope := Scope (Base_Type (Scope (C)));
16211 -- This test only concerns tagged types
16213 if not Is_Tagged_Type (Original_Scope) then
16216 -- If it is _Parent or _Tag, there is no visibility issue
16218 elsif not Comes_From_Source (Original_Comp) then
16221 -- Discriminants are always visible
16223 elsif Ekind (Original_Comp) = E_Discriminant
16224 and then not Has_Unknown_Discriminants (Original_Scope)
16228 -- If we are in the body of an instantiation, the component is visible
16229 -- if the parent type is non-private, or in an enclosing scope. The
16230 -- scope stack is not present when analyzing an instance body, so we
16231 -- must inspect the chain of scopes explicitly.
16233 elsif In_Instance_Body then
16234 if not Is_Private_Type (Scope (C)) then
16242 S := Current_Scope;
16244 and then S /= Standard_Standard
16246 if S = Type_Scope then
16257 -- If the component has been declared in an ancestor which is currently
16258 -- a private type, then it is not visible. The same applies if the
16259 -- component's containing type is not in an open scope and the original
16260 -- component's enclosing type is a visible full view of a private type
16261 -- (which can occur in cases where an attempt is being made to reference
16262 -- a component in a sibling package that is inherited from a visible
16263 -- component of a type in an ancestor package; the component in the
16264 -- sibling package should not be visible even though the component it
16265 -- inherited from is visible). This does not apply however in the case
16266 -- where the scope of the type is a private child unit, or when the
16267 -- parent comes from a local package in which the ancestor is currently
16268 -- visible. The latter suppression of visibility is needed for cases
16269 -- that are tested in B730006.
16271 elsif Is_Private_Type (Original_Scope)
16273 (not Is_Private_Descendant (Type_Scope)
16274 and then not In_Open_Scopes (Type_Scope)
16275 and then Has_Private_Declaration (Original_Scope))
16277 -- If the type derives from an entity in a formal package, there
16278 -- are no additional visible components.
16280 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
16281 N_Formal_Package_Declaration
16285 -- if we are not in the private part of the current package, there
16286 -- are no additional visible components.
16288 elsif Ekind (Scope (Current_Scope)) = E_Package
16289 and then not In_Private_Part (Scope (Current_Scope))
16294 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
16295 and then In_Open_Scopes (Scope (Original_Scope))
16296 and then Is_Local_Type (Type_Scope);
16299 -- There is another weird way in which a component may be invisible
16300 -- when the private and the full view are not derived from the same
16301 -- ancestor. Here is an example :
16303 -- type A1 is tagged record F1 : integer; end record;
16304 -- type A2 is new A1 with record F2 : integer; end record;
16305 -- type T is new A1 with private;
16307 -- type T is new A2 with null record;
16309 -- In this case, the full view of T inherits F1 and F2 but the private
16310 -- view inherits only F1
16314 Ancestor : Entity_Id := Scope (C);
16318 if Ancestor = Original_Scope then
16320 elsif Ancestor = Etype (Ancestor) then
16324 Ancestor := Etype (Ancestor);
16328 end Is_Visible_Component;
16330 --------------------------
16331 -- Make_Class_Wide_Type --
16332 --------------------------
16334 procedure Make_Class_Wide_Type (T : Entity_Id) is
16335 CW_Type : Entity_Id;
16337 Next_E : Entity_Id;
16340 if Present (Class_Wide_Type (T)) then
16342 -- The class-wide type is a partially decorated entity created for a
16343 -- unanalyzed tagged type referenced through a limited with clause.
16344 -- When the tagged type is analyzed, its class-wide type needs to be
16345 -- redecorated. Note that we reuse the entity created by Decorate_
16346 -- Tagged_Type in order to preserve all links.
16348 if Materialize_Entity (Class_Wide_Type (T)) then
16349 CW_Type := Class_Wide_Type (T);
16350 Set_Materialize_Entity (CW_Type, False);
16352 -- The class wide type can have been defined by the partial view, in
16353 -- which case everything is already done.
16359 -- Default case, we need to create a new class-wide type
16363 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
16366 -- Inherit root type characteristics
16368 CW_Name := Chars (CW_Type);
16369 Next_E := Next_Entity (CW_Type);
16370 Copy_Node (T, CW_Type);
16371 Set_Comes_From_Source (CW_Type, False);
16372 Set_Chars (CW_Type, CW_Name);
16373 Set_Parent (CW_Type, Parent (T));
16374 Set_Next_Entity (CW_Type, Next_E);
16376 -- Ensure we have a new freeze node for the class-wide type. The partial
16377 -- view may have freeze action of its own, requiring a proper freeze
16378 -- node, and the same freeze node cannot be shared between the two
16381 Set_Has_Delayed_Freeze (CW_Type);
16382 Set_Freeze_Node (CW_Type, Empty);
16384 -- Customize the class-wide type: It has no prim. op., it cannot be
16385 -- abstract and its Etype points back to the specific root type.
16387 Set_Ekind (CW_Type, E_Class_Wide_Type);
16388 Set_Is_Tagged_Type (CW_Type, True);
16389 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
16390 Set_Is_Abstract_Type (CW_Type, False);
16391 Set_Is_Constrained (CW_Type, False);
16392 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
16394 if Ekind (T) = E_Class_Wide_Subtype then
16395 Set_Etype (CW_Type, Etype (Base_Type (T)));
16397 Set_Etype (CW_Type, T);
16400 -- If this is the class_wide type of a constrained subtype, it does
16401 -- not have discriminants.
16403 Set_Has_Discriminants (CW_Type,
16404 Has_Discriminants (T) and then not Is_Constrained (T));
16406 Set_Has_Unknown_Discriminants (CW_Type, True);
16407 Set_Class_Wide_Type (T, CW_Type);
16408 Set_Equivalent_Type (CW_Type, Empty);
16410 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
16412 Set_Class_Wide_Type (CW_Type, CW_Type);
16413 end Make_Class_Wide_Type;
16419 procedure Make_Index
16421 Related_Nod : Node_Id;
16422 Related_Id : Entity_Id := Empty;
16423 Suffix_Index : Nat := 1;
16424 In_Iter_Schm : Boolean := False)
16428 Def_Id : Entity_Id := Empty;
16429 Found : Boolean := False;
16432 -- For a discrete range used in a constrained array definition and
16433 -- defined by a range, an implicit conversion to the predefined type
16434 -- INTEGER is assumed if each bound is either a numeric literal, a named
16435 -- number, or an attribute, and the type of both bounds (prior to the
16436 -- implicit conversion) is the type universal_integer. Otherwise, both
16437 -- bounds must be of the same discrete type, other than universal
16438 -- integer; this type must be determinable independently of the
16439 -- context, but using the fact that the type must be discrete and that
16440 -- both bounds must have the same type.
16442 -- Character literals also have a universal type in the absence of
16443 -- of additional context, and are resolved to Standard_Character.
16445 if Nkind (I) = N_Range then
16447 -- The index is given by a range constraint. The bounds are known
16448 -- to be of a consistent type.
16450 if not Is_Overloaded (I) then
16453 -- For universal bounds, choose the specific predefined type
16455 if T = Universal_Integer then
16456 T := Standard_Integer;
16458 elsif T = Any_Character then
16459 Ambiguous_Character (Low_Bound (I));
16461 T := Standard_Character;
16464 -- The node may be overloaded because some user-defined operators
16465 -- are available, but if a universal interpretation exists it is
16466 -- also the selected one.
16468 elsif Universal_Interpretation (I) = Universal_Integer then
16469 T := Standard_Integer;
16475 Ind : Interp_Index;
16479 Get_First_Interp (I, Ind, It);
16480 while Present (It.Typ) loop
16481 if Is_Discrete_Type (It.Typ) then
16484 and then not Covers (It.Typ, T)
16485 and then not Covers (T, It.Typ)
16487 Error_Msg_N ("ambiguous bounds in discrete range", I);
16495 Get_Next_Interp (Ind, It);
16498 if T = Any_Type then
16499 Error_Msg_N ("discrete type required for range", I);
16500 Set_Etype (I, Any_Type);
16503 elsif T = Universal_Integer then
16504 T := Standard_Integer;
16509 if not Is_Discrete_Type (T) then
16510 Error_Msg_N ("discrete type required for range", I);
16511 Set_Etype (I, Any_Type);
16515 if Nkind (Low_Bound (I)) = N_Attribute_Reference
16516 and then Attribute_Name (Low_Bound (I)) = Name_First
16517 and then Is_Entity_Name (Prefix (Low_Bound (I)))
16518 and then Is_Type (Entity (Prefix (Low_Bound (I))))
16519 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (I))))
16521 -- The type of the index will be the type of the prefix, as long
16522 -- as the upper bound is 'Last of the same type.
16524 Def_Id := Entity (Prefix (Low_Bound (I)));
16526 if Nkind (High_Bound (I)) /= N_Attribute_Reference
16527 or else Attribute_Name (High_Bound (I)) /= Name_Last
16528 or else not Is_Entity_Name (Prefix (High_Bound (I)))
16529 or else Entity (Prefix (High_Bound (I))) /= Def_Id
16536 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
16538 elsif Nkind (I) = N_Subtype_Indication then
16540 -- The index is given by a subtype with a range constraint
16542 T := Base_Type (Entity (Subtype_Mark (I)));
16544 if not Is_Discrete_Type (T) then
16545 Error_Msg_N ("discrete type required for range", I);
16546 Set_Etype (I, Any_Type);
16550 R := Range_Expression (Constraint (I));
16553 Process_Range_Expr_In_Decl
16554 (R, Entity (Subtype_Mark (I)), In_Iter_Schm => In_Iter_Schm);
16556 elsif Nkind (I) = N_Attribute_Reference then
16558 -- The parser guarantees that the attribute is a RANGE attribute
16560 -- If the node denotes the range of a type mark, that is also the
16561 -- resulting type, and we do no need to create an Itype for it.
16563 if Is_Entity_Name (Prefix (I))
16564 and then Comes_From_Source (I)
16565 and then Is_Type (Entity (Prefix (I)))
16566 and then Is_Discrete_Type (Entity (Prefix (I)))
16568 Def_Id := Entity (Prefix (I));
16571 Analyze_And_Resolve (I);
16575 -- If none of the above, must be a subtype. We convert this to a
16576 -- range attribute reference because in the case of declared first
16577 -- named subtypes, the types in the range reference can be different
16578 -- from the type of the entity. A range attribute normalizes the
16579 -- reference and obtains the correct types for the bounds.
16581 -- This transformation is in the nature of an expansion, is only
16582 -- done if expansion is active. In particular, it is not done on
16583 -- formal generic types, because we need to retain the name of the
16584 -- original index for instantiation purposes.
16587 if not Is_Entity_Name (I) or else not Is_Type (Entity (I)) then
16588 Error_Msg_N ("invalid subtype mark in discrete range ", I);
16589 Set_Etype (I, Any_Integer);
16593 -- The type mark may be that of an incomplete type. It is only
16594 -- now that we can get the full view, previous analysis does
16595 -- not look specifically for a type mark.
16597 Set_Entity (I, Get_Full_View (Entity (I)));
16598 Set_Etype (I, Entity (I));
16599 Def_Id := Entity (I);
16601 if not Is_Discrete_Type (Def_Id) then
16602 Error_Msg_N ("discrete type required for index", I);
16603 Set_Etype (I, Any_Type);
16608 if Expander_Active then
16610 Make_Attribute_Reference (Sloc (I),
16611 Attribute_Name => Name_Range,
16612 Prefix => Relocate_Node (I)));
16614 -- The original was a subtype mark that does not freeze. This
16615 -- means that the rewritten version must not freeze either.
16617 Set_Must_Not_Freeze (I);
16618 Set_Must_Not_Freeze (Prefix (I));
16620 -- Is order critical??? if so, document why, if not
16621 -- use Analyze_And_Resolve
16623 Analyze_And_Resolve (I);
16627 -- If expander is inactive, type is legal, nothing else to construct
16634 if not Is_Discrete_Type (T) then
16635 Error_Msg_N ("discrete type required for range", I);
16636 Set_Etype (I, Any_Type);
16639 elsif T = Any_Type then
16640 Set_Etype (I, Any_Type);
16644 -- We will now create the appropriate Itype to describe the range, but
16645 -- first a check. If we originally had a subtype, then we just label
16646 -- the range with this subtype. Not only is there no need to construct
16647 -- a new subtype, but it is wrong to do so for two reasons:
16649 -- 1. A legality concern, if we have a subtype, it must not freeze,
16650 -- and the Itype would cause freezing incorrectly
16652 -- 2. An efficiency concern, if we created an Itype, it would not be
16653 -- recognized as the same type for the purposes of eliminating
16654 -- checks in some circumstances.
16656 -- We signal this case by setting the subtype entity in Def_Id
16658 if No (Def_Id) then
16660 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
16661 Set_Etype (Def_Id, Base_Type (T));
16663 if Is_Signed_Integer_Type (T) then
16664 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
16666 elsif Is_Modular_Integer_Type (T) then
16667 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
16670 Set_Ekind (Def_Id, E_Enumeration_Subtype);
16671 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
16672 Set_First_Literal (Def_Id, First_Literal (T));
16675 Set_Size_Info (Def_Id, (T));
16676 Set_RM_Size (Def_Id, RM_Size (T));
16677 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
16679 Set_Scalar_Range (Def_Id, R);
16680 Conditional_Delay (Def_Id, T);
16682 -- In the subtype indication case, if the immediate parent of the
16683 -- new subtype is non-static, then the subtype we create is non-
16684 -- static, even if its bounds are static.
16686 if Nkind (I) = N_Subtype_Indication
16687 and then not Is_Static_Subtype (Entity (Subtype_Mark (I)))
16689 Set_Is_Non_Static_Subtype (Def_Id);
16693 -- Final step is to label the index with this constructed type
16695 Set_Etype (I, Def_Id);
16698 ------------------------------
16699 -- Modular_Type_Declaration --
16700 ------------------------------
16702 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16703 Mod_Expr : constant Node_Id := Expression (Def);
16706 procedure Set_Modular_Size (Bits : Int);
16707 -- Sets RM_Size to Bits, and Esize to normal word size above this
16709 ----------------------
16710 -- Set_Modular_Size --
16711 ----------------------
16713 procedure Set_Modular_Size (Bits : Int) is
16715 Set_RM_Size (T, UI_From_Int (Bits));
16720 elsif Bits <= 16 then
16721 Init_Esize (T, 16);
16723 elsif Bits <= 32 then
16724 Init_Esize (T, 32);
16727 Init_Esize (T, System_Max_Binary_Modulus_Power);
16730 if not Non_Binary_Modulus (T)
16731 and then Esize (T) = RM_Size (T)
16733 Set_Is_Known_Valid (T);
16735 end Set_Modular_Size;
16737 -- Start of processing for Modular_Type_Declaration
16740 Analyze_And_Resolve (Mod_Expr, Any_Integer);
16742 Set_Ekind (T, E_Modular_Integer_Type);
16743 Init_Alignment (T);
16744 Set_Is_Constrained (T);
16746 if not Is_OK_Static_Expression (Mod_Expr) then
16747 Flag_Non_Static_Expr
16748 ("non-static expression used for modular type bound!", Mod_Expr);
16749 M_Val := 2 ** System_Max_Binary_Modulus_Power;
16751 M_Val := Expr_Value (Mod_Expr);
16755 Error_Msg_N ("modulus value must be positive", Mod_Expr);
16756 M_Val := 2 ** System_Max_Binary_Modulus_Power;
16759 Set_Modulus (T, M_Val);
16761 -- Create bounds for the modular type based on the modulus given in
16762 -- the type declaration and then analyze and resolve those bounds.
16764 Set_Scalar_Range (T,
16765 Make_Range (Sloc (Mod_Expr),
16766 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
16767 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
16769 -- Properly analyze the literals for the range. We do this manually
16770 -- because we can't go calling Resolve, since we are resolving these
16771 -- bounds with the type, and this type is certainly not complete yet!
16773 Set_Etype (Low_Bound (Scalar_Range (T)), T);
16774 Set_Etype (High_Bound (Scalar_Range (T)), T);
16775 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
16776 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
16778 -- Loop through powers of two to find number of bits required
16780 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
16784 if M_Val = 2 ** Bits then
16785 Set_Modular_Size (Bits);
16790 elsif M_Val < 2 ** Bits then
16791 Check_SPARK_Restriction ("modulus should be a power of 2", T);
16792 Set_Non_Binary_Modulus (T);
16794 if Bits > System_Max_Nonbinary_Modulus_Power then
16795 Error_Msg_Uint_1 :=
16796 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
16798 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
16799 Set_Modular_Size (System_Max_Binary_Modulus_Power);
16803 -- In the non-binary case, set size as per RM 13.3(55)
16805 Set_Modular_Size (Bits);
16812 -- If we fall through, then the size exceed System.Max_Binary_Modulus
16813 -- so we just signal an error and set the maximum size.
16815 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
16816 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
16818 Set_Modular_Size (System_Max_Binary_Modulus_Power);
16819 Init_Alignment (T);
16821 end Modular_Type_Declaration;
16823 --------------------------
16824 -- New_Concatenation_Op --
16825 --------------------------
16827 procedure New_Concatenation_Op (Typ : Entity_Id) is
16828 Loc : constant Source_Ptr := Sloc (Typ);
16831 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
16832 -- Create abbreviated declaration for the formal of a predefined
16833 -- Operator 'Op' of type 'Typ'
16835 --------------------
16836 -- Make_Op_Formal --
16837 --------------------
16839 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
16840 Formal : Entity_Id;
16842 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
16843 Set_Etype (Formal, Typ);
16844 Set_Mechanism (Formal, Default_Mechanism);
16846 end Make_Op_Formal;
16848 -- Start of processing for New_Concatenation_Op
16851 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
16853 Set_Ekind (Op, E_Operator);
16854 Set_Scope (Op, Current_Scope);
16855 Set_Etype (Op, Typ);
16856 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
16857 Set_Is_Immediately_Visible (Op);
16858 Set_Is_Intrinsic_Subprogram (Op);
16859 Set_Has_Completion (Op);
16860 Append_Entity (Op, Current_Scope);
16862 Set_Name_Entity_Id (Name_Op_Concat, Op);
16864 Append_Entity (Make_Op_Formal (Typ, Op), Op);
16865 Append_Entity (Make_Op_Formal (Typ, Op), Op);
16866 end New_Concatenation_Op;
16868 -------------------------
16869 -- OK_For_Limited_Init --
16870 -------------------------
16872 -- ???Check all calls of this, and compare the conditions under which it's
16875 function OK_For_Limited_Init
16877 Exp : Node_Id) return Boolean
16880 return Is_CPP_Constructor_Call (Exp)
16881 or else (Ada_Version >= Ada_2005
16882 and then not Debug_Flag_Dot_L
16883 and then OK_For_Limited_Init_In_05 (Typ, Exp));
16884 end OK_For_Limited_Init;
16886 -------------------------------
16887 -- OK_For_Limited_Init_In_05 --
16888 -------------------------------
16890 function OK_For_Limited_Init_In_05
16892 Exp : Node_Id) return Boolean
16895 -- An object of a limited interface type can be initialized with any
16896 -- expression of a nonlimited descendant type.
16898 if Is_Class_Wide_Type (Typ)
16899 and then Is_Limited_Interface (Typ)
16900 and then not Is_Limited_Type (Etype (Exp))
16905 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
16906 -- case of limited aggregates (including extension aggregates), and
16907 -- function calls. The function call may have been given in prefixed
16908 -- notation, in which case the original node is an indexed component.
16909 -- If the function is parameterless, the original node was an explicit
16910 -- dereference. The function may also be parameterless, in which case
16911 -- the source node is just an identifier.
16913 case Nkind (Original_Node (Exp)) is
16914 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
16917 when N_Identifier =>
16918 return Present (Entity (Original_Node (Exp)))
16919 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
16921 when N_Qualified_Expression =>
16923 OK_For_Limited_Init_In_05
16924 (Typ, Expression (Original_Node (Exp)));
16926 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
16927 -- with a function call, the expander has rewritten the call into an
16928 -- N_Type_Conversion node to force displacement of the pointer to
16929 -- reference the component containing the secondary dispatch table.
16930 -- Otherwise a type conversion is not a legal context.
16931 -- A return statement for a build-in-place function returning a
16932 -- synchronized type also introduces an unchecked conversion.
16934 when N_Type_Conversion |
16935 N_Unchecked_Type_Conversion =>
16936 return not Comes_From_Source (Exp)
16938 OK_For_Limited_Init_In_05
16939 (Typ, Expression (Original_Node (Exp)));
16941 when N_Indexed_Component |
16942 N_Selected_Component |
16943 N_Explicit_Dereference =>
16944 return Nkind (Exp) = N_Function_Call;
16946 -- A use of 'Input is a function call, hence allowed. Normally the
16947 -- attribute will be changed to a call, but the attribute by itself
16948 -- can occur with -gnatc.
16950 when N_Attribute_Reference =>
16951 return Attribute_Name (Original_Node (Exp)) = Name_Input;
16953 -- For a conditional expression, all dependent expressions must be
16954 -- legal constructs.
16956 when N_Conditional_Expression =>
16958 Then_Expr : constant Node_Id :=
16959 Next (First (Expressions (Original_Node (Exp))));
16960 Else_Expr : constant Node_Id := Next (Then_Expr);
16962 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
16963 and then OK_For_Limited_Init_In_05 (Typ, Else_Expr);
16966 when N_Case_Expression =>
16971 Alt := First (Alternatives (Original_Node (Exp)));
16972 while Present (Alt) loop
16973 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
16986 end OK_For_Limited_Init_In_05;
16988 -------------------------------------------
16989 -- Ordinary_Fixed_Point_Type_Declaration --
16990 -------------------------------------------
16992 procedure Ordinary_Fixed_Point_Type_Declaration
16996 Loc : constant Source_Ptr := Sloc (Def);
16997 Delta_Expr : constant Node_Id := Delta_Expression (Def);
16998 RRS : constant Node_Id := Real_Range_Specification (Def);
16999 Implicit_Base : Entity_Id;
17006 Check_Restriction (No_Fixed_Point, Def);
17008 -- Create implicit base type
17011 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
17012 Set_Etype (Implicit_Base, Implicit_Base);
17014 -- Analyze and process delta expression
17016 Analyze_And_Resolve (Delta_Expr, Any_Real);
17018 Check_Delta_Expression (Delta_Expr);
17019 Delta_Val := Expr_Value_R (Delta_Expr);
17021 Set_Delta_Value (Implicit_Base, Delta_Val);
17023 -- Compute default small from given delta, which is the largest power
17024 -- of two that does not exceed the given delta value.
17034 if Delta_Val < Ureal_1 then
17035 while Delta_Val < Tmp loop
17036 Tmp := Tmp / Ureal_2;
17037 Scale := Scale + 1;
17042 Tmp := Tmp * Ureal_2;
17043 exit when Tmp > Delta_Val;
17044 Scale := Scale - 1;
17048 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
17051 Set_Small_Value (Implicit_Base, Small_Val);
17053 -- If no range was given, set a dummy range
17055 if RRS <= Empty_Or_Error then
17056 Low_Val := -Small_Val;
17057 High_Val := Small_Val;
17059 -- Otherwise analyze and process given range
17063 Low : constant Node_Id := Low_Bound (RRS);
17064 High : constant Node_Id := High_Bound (RRS);
17067 Analyze_And_Resolve (Low, Any_Real);
17068 Analyze_And_Resolve (High, Any_Real);
17069 Check_Real_Bound (Low);
17070 Check_Real_Bound (High);
17072 -- Obtain and set the range
17074 Low_Val := Expr_Value_R (Low);
17075 High_Val := Expr_Value_R (High);
17077 if Low_Val > High_Val then
17078 Error_Msg_NE ("?fixed point type& has null range", Def, T);
17083 -- The range for both the implicit base and the declared first subtype
17084 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
17085 -- set a temporary range in place. Note that the bounds of the base
17086 -- type will be widened to be symmetrical and to fill the available
17087 -- bits when the type is frozen.
17089 -- We could do this with all discrete types, and probably should, but
17090 -- we absolutely have to do it for fixed-point, since the end-points
17091 -- of the range and the size are determined by the small value, which
17092 -- could be reset before the freeze point.
17094 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
17095 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
17097 -- Complete definition of first subtype
17099 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
17100 Set_Etype (T, Implicit_Base);
17101 Init_Size_Align (T);
17102 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
17103 Set_Small_Value (T, Small_Val);
17104 Set_Delta_Value (T, Delta_Val);
17105 Set_Is_Constrained (T);
17107 end Ordinary_Fixed_Point_Type_Declaration;
17109 ----------------------------------------
17110 -- Prepare_Private_Subtype_Completion --
17111 ----------------------------------------
17113 procedure Prepare_Private_Subtype_Completion
17115 Related_Nod : Node_Id)
17117 Id_B : constant Entity_Id := Base_Type (Id);
17118 Full_B : constant Entity_Id := Full_View (Id_B);
17122 if Present (Full_B) then
17124 -- The Base_Type is already completed, we can complete the subtype
17125 -- now. We have to create a new entity with the same name, Thus we
17126 -- can't use Create_Itype.
17128 -- This is messy, should be fixed ???
17130 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
17131 Set_Is_Itype (Full);
17132 Set_Associated_Node_For_Itype (Full, Related_Nod);
17133 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
17136 -- The parent subtype may be private, but the base might not, in some
17137 -- nested instances. In that case, the subtype does not need to be
17138 -- exchanged. It would still be nice to make private subtypes and their
17139 -- bases consistent at all times ???
17141 if Is_Private_Type (Id_B) then
17142 Append_Elmt (Id, Private_Dependents (Id_B));
17145 end Prepare_Private_Subtype_Completion;
17147 ---------------------------
17148 -- Process_Discriminants --
17149 ---------------------------
17151 procedure Process_Discriminants
17153 Prev : Entity_Id := Empty)
17155 Elist : constant Elist_Id := New_Elmt_List;
17158 Discr_Number : Uint;
17159 Discr_Type : Entity_Id;
17160 Default_Present : Boolean := False;
17161 Default_Not_Present : Boolean := False;
17164 -- A composite type other than an array type can have discriminants.
17165 -- On entry, the current scope is the composite type.
17167 -- The discriminants are initially entered into the scope of the type
17168 -- via Enter_Name with the default Ekind of E_Void to prevent premature
17169 -- use, as explained at the end of this procedure.
17171 Discr := First (Discriminant_Specifications (N));
17172 while Present (Discr) loop
17173 Enter_Name (Defining_Identifier (Discr));
17175 -- For navigation purposes we add a reference to the discriminant
17176 -- in the entity for the type. If the current declaration is a
17177 -- completion, place references on the partial view. Otherwise the
17178 -- type is the current scope.
17180 if Present (Prev) then
17182 -- The references go on the partial view, if present. If the
17183 -- partial view has discriminants, the references have been
17184 -- generated already.
17186 if not Has_Discriminants (Prev) then
17187 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
17191 (Current_Scope, Defining_Identifier (Discr), 'd');
17194 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
17195 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
17197 -- Ada 2005 (AI-254)
17199 if Present (Access_To_Subprogram_Definition
17200 (Discriminant_Type (Discr)))
17201 and then Protected_Present (Access_To_Subprogram_Definition
17202 (Discriminant_Type (Discr)))
17205 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
17209 Find_Type (Discriminant_Type (Discr));
17210 Discr_Type := Etype (Discriminant_Type (Discr));
17212 if Error_Posted (Discriminant_Type (Discr)) then
17213 Discr_Type := Any_Type;
17217 if Is_Access_Type (Discr_Type) then
17219 -- Ada 2005 (AI-230): Access discriminant allowed in non-limited
17222 if Ada_Version < Ada_2005 then
17223 Check_Access_Discriminant_Requires_Limited
17224 (Discr, Discriminant_Type (Discr));
17227 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
17229 ("(Ada 83) access discriminant not allowed", Discr);
17232 elsif not Is_Discrete_Type (Discr_Type) then
17233 Error_Msg_N ("discriminants must have a discrete or access type",
17234 Discriminant_Type (Discr));
17237 Set_Etype (Defining_Identifier (Discr), Discr_Type);
17239 -- If a discriminant specification includes the assignment compound
17240 -- delimiter followed by an expression, the expression is the default
17241 -- expression of the discriminant; the default expression must be of
17242 -- the type of the discriminant. (RM 3.7.1) Since this expression is
17243 -- a default expression, we do the special preanalysis, since this
17244 -- expression does not freeze (see "Handling of Default and Per-
17245 -- Object Expressions" in spec of package Sem).
17247 if Present (Expression (Discr)) then
17248 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
17250 if Nkind (N) = N_Formal_Type_Declaration then
17252 ("discriminant defaults not allowed for formal type",
17253 Expression (Discr));
17255 -- Flag an error for a tagged type with defaulted discriminants,
17256 -- excluding limited tagged types when compiling for Ada 2012
17257 -- (see AI05-0214).
17259 elsif Is_Tagged_Type (Current_Scope)
17260 and then (not Is_Limited_Type (Current_Scope)
17261 or else Ada_Version < Ada_2012)
17262 and then Comes_From_Source (N)
17264 -- Note: see similar test in Check_Or_Process_Discriminants, to
17265 -- handle the (illegal) case of the completion of an untagged
17266 -- view with discriminants with defaults by a tagged full view.
17267 -- We skip the check if Discr does not come from source, to
17268 -- account for the case of an untagged derived type providing
17269 -- defaults for a renamed discriminant from a private untagged
17270 -- ancestor with a tagged full view (ACATS B460006).
17272 if Ada_Version >= Ada_2012 then
17274 ("discriminants of nonlimited tagged type cannot have"
17276 Expression (Discr));
17279 ("discriminants of tagged type cannot have defaults",
17280 Expression (Discr));
17284 Default_Present := True;
17285 Append_Elmt (Expression (Discr), Elist);
17287 -- Tag the defining identifiers for the discriminants with
17288 -- their corresponding default expressions from the tree.
17290 Set_Discriminant_Default_Value
17291 (Defining_Identifier (Discr), Expression (Discr));
17295 Default_Not_Present := True;
17298 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
17299 -- Discr_Type but with the null-exclusion attribute
17301 if Ada_Version >= Ada_2005 then
17303 -- Ada 2005 (AI-231): Static checks
17305 if Can_Never_Be_Null (Discr_Type) then
17306 Null_Exclusion_Static_Checks (Discr);
17308 elsif Is_Access_Type (Discr_Type)
17309 and then Null_Exclusion_Present (Discr)
17311 -- No need to check itypes because in their case this check
17312 -- was done at their point of creation
17314 and then not Is_Itype (Discr_Type)
17316 if Can_Never_Be_Null (Discr_Type) then
17318 ("`NOT NULL` not allowed (& already excludes null)",
17323 Set_Etype (Defining_Identifier (Discr),
17324 Create_Null_Excluding_Itype
17326 Related_Nod => Discr));
17328 -- Check for improper null exclusion if the type is otherwise
17329 -- legal for a discriminant.
17331 elsif Null_Exclusion_Present (Discr)
17332 and then Is_Discrete_Type (Discr_Type)
17335 ("null exclusion can only apply to an access type", Discr);
17338 -- Ada 2005 (AI-402): access discriminants of nonlimited types
17339 -- can't have defaults. Synchronized types, or types that are
17340 -- explicitly limited are fine, but special tests apply to derived
17341 -- types in generics: in a generic body we have to assume the
17342 -- worst, and therefore defaults are not allowed if the parent is
17343 -- a generic formal private type (see ACATS B370001).
17345 if Is_Access_Type (Discr_Type) and then Default_Present then
17346 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
17347 or else Is_Limited_Record (Current_Scope)
17348 or else Is_Concurrent_Type (Current_Scope)
17349 or else Is_Concurrent_Record_Type (Current_Scope)
17350 or else Ekind (Current_Scope) = E_Limited_Private_Type
17352 if not Is_Derived_Type (Current_Scope)
17353 or else not Is_Generic_Type (Etype (Current_Scope))
17354 or else not In_Package_Body (Scope (Etype (Current_Scope)))
17355 or else Limited_Present
17356 (Type_Definition (Parent (Current_Scope)))
17361 Error_Msg_N ("access discriminants of nonlimited types",
17362 Expression (Discr));
17363 Error_Msg_N ("\cannot have defaults", Expression (Discr));
17366 elsif Present (Expression (Discr)) then
17368 ("(Ada 2005) access discriminants of nonlimited types",
17369 Expression (Discr));
17370 Error_Msg_N ("\cannot have defaults", Expression (Discr));
17378 -- An element list consisting of the default expressions of the
17379 -- discriminants is constructed in the above loop and used to set
17380 -- the Discriminant_Constraint attribute for the type. If an object
17381 -- is declared of this (record or task) type without any explicit
17382 -- discriminant constraint given, this element list will form the
17383 -- actual parameters for the corresponding initialization procedure
17386 Set_Discriminant_Constraint (Current_Scope, Elist);
17387 Set_Stored_Constraint (Current_Scope, No_Elist);
17389 -- Default expressions must be provided either for all or for none
17390 -- of the discriminants of a discriminant part. (RM 3.7.1)
17392 if Default_Present and then Default_Not_Present then
17394 ("incomplete specification of defaults for discriminants", N);
17397 -- The use of the name of a discriminant is not allowed in default
17398 -- expressions of a discriminant part if the specification of the
17399 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
17401 -- To detect this, the discriminant names are entered initially with an
17402 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
17403 -- attempt to use a void entity (for example in an expression that is
17404 -- type-checked) produces the error message: premature usage. Now after
17405 -- completing the semantic analysis of the discriminant part, we can set
17406 -- the Ekind of all the discriminants appropriately.
17408 Discr := First (Discriminant_Specifications (N));
17409 Discr_Number := Uint_1;
17410 while Present (Discr) loop
17411 Id := Defining_Identifier (Discr);
17412 Set_Ekind (Id, E_Discriminant);
17413 Init_Component_Location (Id);
17415 Set_Discriminant_Number (Id, Discr_Number);
17417 -- Make sure this is always set, even in illegal programs
17419 Set_Corresponding_Discriminant (Id, Empty);
17421 -- Initialize the Original_Record_Component to the entity itself.
17422 -- Inherit_Components will propagate the right value to
17423 -- discriminants in derived record types.
17425 Set_Original_Record_Component (Id, Id);
17427 -- Create the discriminal for the discriminant
17429 Build_Discriminal (Id);
17432 Discr_Number := Discr_Number + 1;
17435 Set_Has_Discriminants (Current_Scope);
17436 end Process_Discriminants;
17438 -----------------------
17439 -- Process_Full_View --
17440 -----------------------
17442 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
17443 Priv_Parent : Entity_Id;
17444 Full_Parent : Entity_Id;
17445 Full_Indic : Node_Id;
17447 procedure Collect_Implemented_Interfaces
17449 Ifaces : Elist_Id);
17450 -- Ada 2005: Gather all the interfaces that Typ directly or
17451 -- inherently implements. Duplicate entries are not added to
17452 -- the list Ifaces.
17454 ------------------------------------
17455 -- Collect_Implemented_Interfaces --
17456 ------------------------------------
17458 procedure Collect_Implemented_Interfaces
17463 Iface_Elmt : Elmt_Id;
17466 -- Abstract interfaces are only associated with tagged record types
17468 if not Is_Tagged_Type (Typ)
17469 or else not Is_Record_Type (Typ)
17474 -- Recursively climb to the ancestors
17476 if Etype (Typ) /= Typ
17478 -- Protect the frontend against wrong cyclic declarations like:
17480 -- type B is new A with private;
17481 -- type C is new A with private;
17483 -- type B is new C with null record;
17484 -- type C is new B with null record;
17486 and then Etype (Typ) /= Priv_T
17487 and then Etype (Typ) /= Full_T
17489 -- Keep separate the management of private type declarations
17491 if Ekind (Typ) = E_Record_Type_With_Private then
17493 -- Handle the following erroneous case:
17494 -- type Private_Type is tagged private;
17496 -- type Private_Type is new Type_Implementing_Iface;
17498 if Present (Full_View (Typ))
17499 and then Etype (Typ) /= Full_View (Typ)
17501 if Is_Interface (Etype (Typ)) then
17502 Append_Unique_Elmt (Etype (Typ), Ifaces);
17505 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
17508 -- Non-private types
17511 if Is_Interface (Etype (Typ)) then
17512 Append_Unique_Elmt (Etype (Typ), Ifaces);
17515 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
17519 -- Handle entities in the list of abstract interfaces
17521 if Present (Interfaces (Typ)) then
17522 Iface_Elmt := First_Elmt (Interfaces (Typ));
17523 while Present (Iface_Elmt) loop
17524 Iface := Node (Iface_Elmt);
17526 pragma Assert (Is_Interface (Iface));
17528 if not Contain_Interface (Iface, Ifaces) then
17529 Append_Elmt (Iface, Ifaces);
17530 Collect_Implemented_Interfaces (Iface, Ifaces);
17533 Next_Elmt (Iface_Elmt);
17536 end Collect_Implemented_Interfaces;
17538 -- Start of processing for Process_Full_View
17541 -- First some sanity checks that must be done after semantic
17542 -- decoration of the full view and thus cannot be placed with other
17543 -- similar checks in Find_Type_Name
17545 if not Is_Limited_Type (Priv_T)
17546 and then (Is_Limited_Type (Full_T)
17547 or else Is_Limited_Composite (Full_T))
17549 if In_Instance then
17553 ("completion of nonlimited type cannot be limited", Full_T);
17554 Explain_Limited_Type (Full_T, Full_T);
17557 elsif Is_Abstract_Type (Full_T)
17558 and then not Is_Abstract_Type (Priv_T)
17561 ("completion of nonabstract type cannot be abstract", Full_T);
17563 elsif Is_Tagged_Type (Priv_T)
17564 and then Is_Limited_Type (Priv_T)
17565 and then not Is_Limited_Type (Full_T)
17567 -- If pragma CPP_Class was applied to the private declaration
17568 -- propagate the limitedness to the full-view
17570 if Is_CPP_Class (Priv_T) then
17571 Set_Is_Limited_Record (Full_T);
17573 -- GNAT allow its own definition of Limited_Controlled to disobey
17574 -- this rule in order in ease the implementation. This test is safe
17575 -- because Root_Controlled is defined in a child of System that
17576 -- normal programs are not supposed to use.
17578 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
17579 Set_Is_Limited_Composite (Full_T);
17582 ("completion of limited tagged type must be limited", Full_T);
17585 elsif Is_Generic_Type (Priv_T) then
17586 Error_Msg_N ("generic type cannot have a completion", Full_T);
17589 -- Check that ancestor interfaces of private and full views are
17590 -- consistent. We omit this check for synchronized types because
17591 -- they are performed on the corresponding record type when frozen.
17593 if Ada_Version >= Ada_2005
17594 and then Is_Tagged_Type (Priv_T)
17595 and then Is_Tagged_Type (Full_T)
17596 and then not Is_Concurrent_Type (Full_T)
17600 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
17601 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
17604 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
17605 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
17607 -- Ada 2005 (AI-251): The partial view shall be a descendant of
17608 -- an interface type if and only if the full type is descendant
17609 -- of the interface type (AARM 7.3 (7.3/2)).
17611 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
17613 if Present (Iface) then
17615 ("interface & not implemented by full type " &
17616 "(RM-2005 7.3 (7.3/2))", Priv_T, Iface);
17619 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
17621 if Present (Iface) then
17623 ("interface & not implemented by partial view " &
17624 "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
17629 if Is_Tagged_Type (Priv_T)
17630 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
17631 and then Is_Derived_Type (Full_T)
17633 Priv_Parent := Etype (Priv_T);
17635 -- The full view of a private extension may have been transformed
17636 -- into an unconstrained derived type declaration and a subtype
17637 -- declaration (see build_derived_record_type for details).
17639 if Nkind (N) = N_Subtype_Declaration then
17640 Full_Indic := Subtype_Indication (N);
17641 Full_Parent := Etype (Base_Type (Full_T));
17643 Full_Indic := Subtype_Indication (Type_Definition (N));
17644 Full_Parent := Etype (Full_T);
17647 -- Check that the parent type of the full type is a descendant of
17648 -- the ancestor subtype given in the private extension. If either
17649 -- entity has an Etype equal to Any_Type then we had some previous
17650 -- error situation [7.3(8)].
17652 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
17655 -- Ada 2005 (AI-251): Interfaces in the full-typ can be given in
17656 -- any order. Therefore we don't have to check that its parent must
17657 -- be a descendant of the parent of the private type declaration.
17659 elsif Is_Interface (Priv_Parent)
17660 and then Is_Interface (Full_Parent)
17664 -- Ada 2005 (AI-251): If the parent of the private type declaration
17665 -- is an interface there is no need to check that it is an ancestor
17666 -- of the associated full type declaration. The required tests for
17667 -- this case are performed by Build_Derived_Record_Type.
17669 elsif not Is_Interface (Base_Type (Priv_Parent))
17670 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
17673 ("parent of full type must descend from parent"
17674 & " of private extension", Full_Indic);
17676 -- First check a formal restriction, and then proceed with checking
17677 -- Ada rules. Since the formal restriction is not a serious error, we
17678 -- don't prevent further error detection for this check, hence the
17683 -- In formal mode, when completing a private extension the type
17684 -- named in the private part must be exactly the same as that
17685 -- named in the visible part.
17687 if Priv_Parent /= Full_Parent then
17688 Error_Msg_Name_1 := Chars (Priv_Parent);
17689 Check_SPARK_Restriction ("% expected", Full_Indic);
17692 -- Check the rules of 7.3(10): if the private extension inherits
17693 -- known discriminants, then the full type must also inherit those
17694 -- discriminants from the same (ancestor) type, and the parent
17695 -- subtype of the full type must be constrained if and only if
17696 -- the ancestor subtype of the private extension is constrained.
17698 if No (Discriminant_Specifications (Parent (Priv_T)))
17699 and then not Has_Unknown_Discriminants (Priv_T)
17700 and then Has_Discriminants (Base_Type (Priv_Parent))
17703 Priv_Indic : constant Node_Id :=
17704 Subtype_Indication (Parent (Priv_T));
17706 Priv_Constr : constant Boolean :=
17707 Is_Constrained (Priv_Parent)
17709 Nkind (Priv_Indic) = N_Subtype_Indication
17711 Is_Constrained (Entity (Priv_Indic));
17713 Full_Constr : constant Boolean :=
17714 Is_Constrained (Full_Parent)
17716 Nkind (Full_Indic) = N_Subtype_Indication
17718 Is_Constrained (Entity (Full_Indic));
17720 Priv_Discr : Entity_Id;
17721 Full_Discr : Entity_Id;
17724 Priv_Discr := First_Discriminant (Priv_Parent);
17725 Full_Discr := First_Discriminant (Full_Parent);
17726 while Present (Priv_Discr) and then Present (Full_Discr) loop
17727 if Original_Record_Component (Priv_Discr) =
17728 Original_Record_Component (Full_Discr)
17730 Corresponding_Discriminant (Priv_Discr) =
17731 Corresponding_Discriminant (Full_Discr)
17738 Next_Discriminant (Priv_Discr);
17739 Next_Discriminant (Full_Discr);
17742 if Present (Priv_Discr) or else Present (Full_Discr) then
17744 ("full view must inherit discriminants of the parent"
17745 & " type used in the private extension", Full_Indic);
17747 elsif Priv_Constr and then not Full_Constr then
17749 ("parent subtype of full type must be constrained",
17752 elsif Full_Constr and then not Priv_Constr then
17754 ("parent subtype of full type must be unconstrained",
17759 -- Check the rules of 7.3(12): if a partial view has neither
17760 -- known or unknown discriminants, then the full type
17761 -- declaration shall define a definite subtype.
17763 elsif not Has_Unknown_Discriminants (Priv_T)
17764 and then not Has_Discriminants (Priv_T)
17765 and then not Is_Constrained (Full_T)
17768 ("full view must define a constrained type if partial view"
17769 & " has no discriminants", Full_T);
17772 -- ??????? Do we implement the following properly ?????
17773 -- If the ancestor subtype of a private extension has constrained
17774 -- discriminants, then the parent subtype of the full view shall
17775 -- impose a statically matching constraint on those discriminants
17780 -- For untagged types, verify that a type without discriminants
17781 -- is not completed with an unconstrained type.
17783 if not Is_Indefinite_Subtype (Priv_T)
17784 and then Is_Indefinite_Subtype (Full_T)
17786 Error_Msg_N ("full view of type must be definite subtype", Full_T);
17790 -- AI-419: verify that the use of "limited" is consistent
17793 Orig_Decl : constant Node_Id := Original_Node (N);
17796 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
17797 and then not Limited_Present (Parent (Priv_T))
17798 and then not Synchronized_Present (Parent (Priv_T))
17799 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
17801 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
17802 and then Limited_Present (Type_Definition (Orig_Decl))
17805 ("full view of non-limited extension cannot be limited", N);
17809 -- Ada 2005 (AI-443): A synchronized private extension must be
17810 -- completed by a task or protected type.
17812 if Ada_Version >= Ada_2005
17813 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
17814 and then Synchronized_Present (Parent (Priv_T))
17815 and then not Is_Concurrent_Type (Full_T)
17817 Error_Msg_N ("full view of synchronized extension must " &
17818 "be synchronized type", N);
17821 -- Ada 2005 AI-363: if the full view has discriminants with
17822 -- defaults, it is illegal to declare constrained access subtypes
17823 -- whose designated type is the current type. This allows objects
17824 -- of the type that are declared in the heap to be unconstrained.
17826 if not Has_Unknown_Discriminants (Priv_T)
17827 and then not Has_Discriminants (Priv_T)
17828 and then Has_Discriminants (Full_T)
17830 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
17832 Set_Has_Constrained_Partial_View (Full_T);
17833 Set_Has_Constrained_Partial_View (Priv_T);
17836 -- Create a full declaration for all its subtypes recorded in
17837 -- Private_Dependents and swap them similarly to the base type. These
17838 -- are subtypes that have been define before the full declaration of
17839 -- the private type. We also swap the entry in Private_Dependents list
17840 -- so we can properly restore the private view on exit from the scope.
17843 Priv_Elmt : Elmt_Id;
17848 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
17849 while Present (Priv_Elmt) loop
17850 Priv := Node (Priv_Elmt);
17852 if Ekind_In (Priv, E_Private_Subtype,
17853 E_Limited_Private_Subtype,
17854 E_Record_Subtype_With_Private)
17856 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
17857 Set_Is_Itype (Full);
17858 Set_Parent (Full, Parent (Priv));
17859 Set_Associated_Node_For_Itype (Full, N);
17861 -- Now we need to complete the private subtype, but since the
17862 -- base type has already been swapped, we must also swap the
17863 -- subtypes (and thus, reverse the arguments in the call to
17864 -- Complete_Private_Subtype).
17866 Copy_And_Swap (Priv, Full);
17867 Complete_Private_Subtype (Full, Priv, Full_T, N);
17868 Replace_Elmt (Priv_Elmt, Full);
17871 Next_Elmt (Priv_Elmt);
17875 -- If the private view was tagged, copy the new primitive operations
17876 -- from the private view to the full view.
17878 if Is_Tagged_Type (Full_T) then
17880 Disp_Typ : Entity_Id;
17881 Full_List : Elist_Id;
17883 Prim_Elmt : Elmt_Id;
17884 Priv_List : Elist_Id;
17888 L : Elist_Id) return Boolean;
17889 -- Determine whether list L contains element E
17897 L : Elist_Id) return Boolean
17899 List_Elmt : Elmt_Id;
17902 List_Elmt := First_Elmt (L);
17903 while Present (List_Elmt) loop
17904 if Node (List_Elmt) = E then
17908 Next_Elmt (List_Elmt);
17914 -- Start of processing
17917 if Is_Tagged_Type (Priv_T) then
17918 Priv_List := Primitive_Operations (Priv_T);
17919 Prim_Elmt := First_Elmt (Priv_List);
17921 -- In the case of a concurrent type completing a private tagged
17922 -- type, primitives may have been declared in between the two
17923 -- views. These subprograms need to be wrapped the same way
17924 -- entries and protected procedures are handled because they
17925 -- cannot be directly shared by the two views.
17927 if Is_Concurrent_Type (Full_T) then
17929 Conc_Typ : constant Entity_Id :=
17930 Corresponding_Record_Type (Full_T);
17931 Curr_Nod : Node_Id := Parent (Conc_Typ);
17932 Wrap_Spec : Node_Id;
17935 while Present (Prim_Elmt) loop
17936 Prim := Node (Prim_Elmt);
17938 if Comes_From_Source (Prim)
17939 and then not Is_Abstract_Subprogram (Prim)
17942 Make_Subprogram_Declaration (Sloc (Prim),
17946 Obj_Typ => Conc_Typ,
17948 Parameter_Specifications (
17951 Insert_After (Curr_Nod, Wrap_Spec);
17952 Curr_Nod := Wrap_Spec;
17954 Analyze (Wrap_Spec);
17957 Next_Elmt (Prim_Elmt);
17963 -- For non-concurrent types, transfer explicit primitives, but
17964 -- omit those inherited from the parent of the private view
17965 -- since they will be re-inherited later on.
17968 Full_List := Primitive_Operations (Full_T);
17970 while Present (Prim_Elmt) loop
17971 Prim := Node (Prim_Elmt);
17973 if Comes_From_Source (Prim)
17974 and then not Contains (Prim, Full_List)
17976 Append_Elmt (Prim, Full_List);
17979 Next_Elmt (Prim_Elmt);
17983 -- Untagged private view
17986 Full_List := Primitive_Operations (Full_T);
17988 -- In this case the partial view is untagged, so here we locate
17989 -- all of the earlier primitives that need to be treated as
17990 -- dispatching (those that appear between the two views). Note
17991 -- that these additional operations must all be new operations
17992 -- (any earlier operations that override inherited operations
17993 -- of the full view will already have been inserted in the
17994 -- primitives list, marked by Check_Operation_From_Private_View
17995 -- as dispatching. Note that implicit "/=" operators are
17996 -- excluded from being added to the primitives list since they
17997 -- shouldn't be treated as dispatching (tagged "/=" is handled
18000 Prim := Next_Entity (Full_T);
18001 while Present (Prim) and then Prim /= Priv_T loop
18002 if Ekind_In (Prim, E_Procedure, E_Function) then
18003 Disp_Typ := Find_Dispatching_Type (Prim);
18005 if Disp_Typ = Full_T
18006 and then (Chars (Prim) /= Name_Op_Ne
18007 or else Comes_From_Source (Prim))
18009 Check_Controlling_Formals (Full_T, Prim);
18011 if not Is_Dispatching_Operation (Prim) then
18012 Append_Elmt (Prim, Full_List);
18013 Set_Is_Dispatching_Operation (Prim, True);
18014 Set_DT_Position (Prim, No_Uint);
18017 elsif Is_Dispatching_Operation (Prim)
18018 and then Disp_Typ /= Full_T
18021 -- Verify that it is not otherwise controlled by a
18022 -- formal or a return value of type T.
18024 Check_Controlling_Formals (Disp_Typ, Prim);
18028 Next_Entity (Prim);
18032 -- For the tagged case, the two views can share the same primitive
18033 -- operations list and the same class-wide type. Update attributes
18034 -- of the class-wide type which depend on the full declaration.
18036 if Is_Tagged_Type (Priv_T) then
18037 Set_Direct_Primitive_Operations (Priv_T, Full_List);
18038 Set_Class_Wide_Type
18039 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
18041 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
18046 -- Ada 2005 AI 161: Check preelaboratable initialization consistency
18048 if Known_To_Have_Preelab_Init (Priv_T) then
18050 -- Case where there is a pragma Preelaborable_Initialization. We
18051 -- always allow this in predefined units, which is a bit of a kludge,
18052 -- but it means we don't have to struggle to meet the requirements in
18053 -- the RM for having Preelaborable Initialization. Otherwise we
18054 -- require that the type meets the RM rules. But we can't check that
18055 -- yet, because of the rule about overriding Initialize, so we simply
18056 -- set a flag that will be checked at freeze time.
18058 if not In_Predefined_Unit (Full_T) then
18059 Set_Must_Have_Preelab_Init (Full_T);
18063 -- If pragma CPP_Class was applied to the private type declaration,
18064 -- propagate it now to the full type declaration.
18066 if Is_CPP_Class (Priv_T) then
18067 Set_Is_CPP_Class (Full_T);
18068 Set_Convention (Full_T, Convention_CPP);
18071 -- If the private view has user specified stream attributes, then so has
18074 -- Why the test, how could these flags be already set in Full_T ???
18076 if Has_Specified_Stream_Read (Priv_T) then
18077 Set_Has_Specified_Stream_Read (Full_T);
18080 if Has_Specified_Stream_Write (Priv_T) then
18081 Set_Has_Specified_Stream_Write (Full_T);
18084 if Has_Specified_Stream_Input (Priv_T) then
18085 Set_Has_Specified_Stream_Input (Full_T);
18088 if Has_Specified_Stream_Output (Priv_T) then
18089 Set_Has_Specified_Stream_Output (Full_T);
18092 -- Propagate invariants to full type
18094 if Has_Invariants (Priv_T) then
18095 Set_Has_Invariants (Full_T);
18096 Set_Invariant_Procedure (Full_T, Invariant_Procedure (Priv_T));
18099 if Has_Inheritable_Invariants (Priv_T) then
18100 Set_Has_Inheritable_Invariants (Full_T);
18103 -- Propagate predicates to full type
18105 if Has_Predicates (Priv_T) then
18106 Set_Predicate_Function (Priv_T, Predicate_Function (Full_T));
18107 Set_Has_Predicates (Priv_T);
18109 end Process_Full_View;
18111 -----------------------------------
18112 -- Process_Incomplete_Dependents --
18113 -----------------------------------
18115 procedure Process_Incomplete_Dependents
18117 Full_T : Entity_Id;
18120 Inc_Elmt : Elmt_Id;
18121 Priv_Dep : Entity_Id;
18122 New_Subt : Entity_Id;
18124 Disc_Constraint : Elist_Id;
18127 if No (Private_Dependents (Inc_T)) then
18131 -- Itypes that may be generated by the completion of an incomplete
18132 -- subtype are not used by the back-end and not attached to the tree.
18133 -- They are created only for constraint-checking purposes.
18135 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
18136 while Present (Inc_Elmt) loop
18137 Priv_Dep := Node (Inc_Elmt);
18139 if Ekind (Priv_Dep) = E_Subprogram_Type then
18141 -- An Access_To_Subprogram type may have a return type or a
18142 -- parameter type that is incomplete. Replace with the full view.
18144 if Etype (Priv_Dep) = Inc_T then
18145 Set_Etype (Priv_Dep, Full_T);
18149 Formal : Entity_Id;
18152 Formal := First_Formal (Priv_Dep);
18153 while Present (Formal) loop
18154 if Etype (Formal) = Inc_T then
18155 Set_Etype (Formal, Full_T);
18158 Next_Formal (Formal);
18162 elsif Is_Overloadable (Priv_Dep) then
18164 -- If a subprogram in the incomplete dependents list is primitive
18165 -- for a tagged full type then mark it as a dispatching operation,
18166 -- check whether it overrides an inherited subprogram, and check
18167 -- restrictions on its controlling formals. Note that a protected
18168 -- operation is never dispatching: only its wrapper operation
18169 -- (which has convention Ada) is.
18171 if Is_Tagged_Type (Full_T)
18172 and then Is_Primitive (Priv_Dep)
18173 and then Convention (Priv_Dep) /= Convention_Protected
18175 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
18176 Set_Is_Dispatching_Operation (Priv_Dep);
18177 Check_Controlling_Formals (Full_T, Priv_Dep);
18180 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
18182 -- Can happen during processing of a body before the completion
18183 -- of a TA type. Ignore, because spec is also on dependent list.
18187 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
18188 -- corresponding subtype of the full view.
18190 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
18191 Set_Subtype_Indication
18192 (Parent (Priv_Dep), New_Reference_To (Full_T, Sloc (Priv_Dep)));
18193 Set_Etype (Priv_Dep, Full_T);
18194 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
18195 Set_Analyzed (Parent (Priv_Dep), False);
18197 -- Reanalyze the declaration, suppressing the call to
18198 -- Enter_Name to avoid duplicate names.
18200 Analyze_Subtype_Declaration
18201 (N => Parent (Priv_Dep),
18204 -- Dependent is a subtype
18207 -- We build a new subtype indication using the full view of the
18208 -- incomplete parent. The discriminant constraints have been
18209 -- elaborated already at the point of the subtype declaration.
18211 New_Subt := Create_Itype (E_Void, N);
18213 if Has_Discriminants (Full_T) then
18214 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
18216 Disc_Constraint := No_Elist;
18219 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
18220 Set_Full_View (Priv_Dep, New_Subt);
18223 Next_Elmt (Inc_Elmt);
18225 end Process_Incomplete_Dependents;
18227 --------------------------------
18228 -- Process_Range_Expr_In_Decl --
18229 --------------------------------
18231 procedure Process_Range_Expr_In_Decl
18234 Check_List : List_Id := Empty_List;
18235 R_Check_Off : Boolean := False;
18236 In_Iter_Schm : Boolean := False)
18239 R_Checks : Check_Result;
18240 Insert_Node : Node_Id;
18241 Def_Id : Entity_Id;
18244 Analyze_And_Resolve (R, Base_Type (T));
18246 if Nkind (R) = N_Range then
18248 -- In SPARK, all ranges should be static, with the exception of the
18249 -- discrete type definition of a loop parameter specification.
18251 if not In_Iter_Schm
18252 and then not Is_Static_Range (R)
18254 Check_SPARK_Restriction ("range should be static", R);
18257 Lo := Low_Bound (R);
18258 Hi := High_Bound (R);
18260 -- We need to ensure validity of the bounds here, because if we
18261 -- go ahead and do the expansion, then the expanded code will get
18262 -- analyzed with range checks suppressed and we miss the check.
18264 Validity_Check_Range (R);
18266 -- If there were errors in the declaration, try and patch up some
18267 -- common mistakes in the bounds. The cases handled are literals
18268 -- which are Integer where the expected type is Real and vice versa.
18269 -- These corrections allow the compilation process to proceed further
18270 -- along since some basic assumptions of the format of the bounds
18273 if Etype (R) = Any_Type then
18275 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
18277 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
18279 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
18281 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
18283 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
18285 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
18287 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
18289 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
18296 -- If the bounds of the range have been mistakenly given as string
18297 -- literals (perhaps in place of character literals), then an error
18298 -- has already been reported, but we rewrite the string literal as a
18299 -- bound of the range's type to avoid blowups in later processing
18300 -- that looks at static values.
18302 if Nkind (Lo) = N_String_Literal then
18304 Make_Attribute_Reference (Sloc (Lo),
18305 Attribute_Name => Name_First,
18306 Prefix => New_Reference_To (T, Sloc (Lo))));
18307 Analyze_And_Resolve (Lo);
18310 if Nkind (Hi) = N_String_Literal then
18312 Make_Attribute_Reference (Sloc (Hi),
18313 Attribute_Name => Name_First,
18314 Prefix => New_Reference_To (T, Sloc (Hi))));
18315 Analyze_And_Resolve (Hi);
18318 -- If bounds aren't scalar at this point then exit, avoiding
18319 -- problems with further processing of the range in this procedure.
18321 if not Is_Scalar_Type (Etype (Lo)) then
18325 -- Resolve (actually Sem_Eval) has checked that the bounds are in
18326 -- then range of the base type. Here we check whether the bounds
18327 -- are in the range of the subtype itself. Note that if the bounds
18328 -- represent the null range the Constraint_Error exception should
18331 -- ??? The following code should be cleaned up as follows
18333 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
18334 -- is done in the call to Range_Check (R, T); below
18336 -- 2. The use of R_Check_Off should be investigated and possibly
18337 -- removed, this would clean up things a bit.
18339 if Is_Null_Range (Lo, Hi) then
18343 -- Capture values of bounds and generate temporaries for them
18344 -- if needed, before applying checks, since checks may cause
18345 -- duplication of the expression without forcing evaluation.
18347 -- The forced evaluation removes side effects from expressions,
18348 -- which should occur also in Alfa mode. Otherwise, we end up with
18349 -- unexpected insertions of actions at places where this is not
18350 -- supposed to occur, e.g. on default parameters of a call.
18352 if Expander_Active then
18353 Force_Evaluation (Lo);
18354 Force_Evaluation (Hi);
18357 -- We use a flag here instead of suppressing checks on the
18358 -- type because the type we check against isn't necessarily
18359 -- the place where we put the check.
18361 if not R_Check_Off then
18362 R_Checks := Get_Range_Checks (R, T);
18364 -- Look up tree to find an appropriate insertion point. We
18365 -- can't just use insert_actions because later processing
18366 -- depends on the insertion node. Prior to Ada 2012 the
18367 -- insertion point could only be a declaration or a loop, but
18368 -- quantified expressions can appear within any context in an
18369 -- expression, and the insertion point can be any statement,
18370 -- pragma, or declaration.
18372 Insert_Node := Parent (R);
18373 while Present (Insert_Node) loop
18375 Nkind (Insert_Node) in N_Declaration
18378 (Insert_Node, N_Component_Declaration,
18379 N_Loop_Parameter_Specification,
18380 N_Function_Specification,
18381 N_Procedure_Specification);
18383 exit when Nkind (Insert_Node) in N_Later_Decl_Item
18384 or else Nkind (Insert_Node) in
18385 N_Statement_Other_Than_Procedure_Call
18386 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
18389 Insert_Node := Parent (Insert_Node);
18392 -- Why would Type_Decl not be present??? Without this test,
18393 -- short regression tests fail.
18395 if Present (Insert_Node) then
18397 -- Case of loop statement. Verify that the range is part
18398 -- of the subtype indication of the iteration scheme.
18400 if Nkind (Insert_Node) = N_Loop_Statement then
18405 Indic := Parent (R);
18406 while Present (Indic)
18407 and then Nkind (Indic) /= N_Subtype_Indication
18409 Indic := Parent (Indic);
18412 if Present (Indic) then
18413 Def_Id := Etype (Subtype_Mark (Indic));
18415 Insert_Range_Checks
18419 Sloc (Insert_Node),
18421 Do_Before => True);
18425 -- Insertion before a declaration. If the declaration
18426 -- includes discriminants, the list of applicable checks
18427 -- is given by the caller.
18429 elsif Nkind (Insert_Node) in N_Declaration then
18430 Def_Id := Defining_Identifier (Insert_Node);
18432 if (Ekind (Def_Id) = E_Record_Type
18433 and then Depends_On_Discriminant (R))
18435 (Ekind (Def_Id) = E_Protected_Type
18436 and then Has_Discriminants (Def_Id))
18438 Append_Range_Checks
18440 Check_List, Def_Id, Sloc (Insert_Node), R);
18443 Insert_Range_Checks
18445 Insert_Node, Def_Id, Sloc (Insert_Node), R);
18449 -- Insertion before a statement. Range appears in the
18450 -- context of a quantified expression. Insertion will
18451 -- take place when expression is expanded.
18460 -- Case of other than an explicit N_Range node
18462 -- The forced evaluation removes side effects from expressions, which
18463 -- should occur also in Alfa mode. Otherwise, we end up with unexpected
18464 -- insertions of actions at places where this is not supposed to occur,
18465 -- e.g. on default parameters of a call.
18467 elsif Expander_Active then
18468 Get_Index_Bounds (R, Lo, Hi);
18469 Force_Evaluation (Lo);
18470 Force_Evaluation (Hi);
18472 end Process_Range_Expr_In_Decl;
18474 --------------------------------------
18475 -- Process_Real_Range_Specification --
18476 --------------------------------------
18478 procedure Process_Real_Range_Specification (Def : Node_Id) is
18479 Spec : constant Node_Id := Real_Range_Specification (Def);
18482 Err : Boolean := False;
18484 procedure Analyze_Bound (N : Node_Id);
18485 -- Analyze and check one bound
18487 -------------------
18488 -- Analyze_Bound --
18489 -------------------
18491 procedure Analyze_Bound (N : Node_Id) is
18493 Analyze_And_Resolve (N, Any_Real);
18495 if not Is_OK_Static_Expression (N) then
18496 Flag_Non_Static_Expr
18497 ("bound in real type definition is not static!", N);
18502 -- Start of processing for Process_Real_Range_Specification
18505 if Present (Spec) then
18506 Lo := Low_Bound (Spec);
18507 Hi := High_Bound (Spec);
18508 Analyze_Bound (Lo);
18509 Analyze_Bound (Hi);
18511 -- If error, clear away junk range specification
18514 Set_Real_Range_Specification (Def, Empty);
18517 end Process_Real_Range_Specification;
18519 ---------------------
18520 -- Process_Subtype --
18521 ---------------------
18523 function Process_Subtype
18525 Related_Nod : Node_Id;
18526 Related_Id : Entity_Id := Empty;
18527 Suffix : Character := ' ') return Entity_Id
18530 Def_Id : Entity_Id;
18531 Error_Node : Node_Id;
18532 Full_View_Id : Entity_Id;
18533 Subtype_Mark_Id : Entity_Id;
18535 May_Have_Null_Exclusion : Boolean;
18537 procedure Check_Incomplete (T : Entity_Id);
18538 -- Called to verify that an incomplete type is not used prematurely
18540 ----------------------
18541 -- Check_Incomplete --
18542 ----------------------
18544 procedure Check_Incomplete (T : Entity_Id) is
18546 -- Ada 2005 (AI-412): Incomplete subtypes are legal
18548 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
18550 not (Ada_Version >= Ada_2005
18552 (Nkind (Parent (T)) = N_Subtype_Declaration
18554 (Nkind (Parent (T)) = N_Subtype_Indication
18555 and then Nkind (Parent (Parent (T))) =
18556 N_Subtype_Declaration)))
18558 Error_Msg_N ("invalid use of type before its full declaration", T);
18560 end Check_Incomplete;
18562 -- Start of processing for Process_Subtype
18565 -- Case of no constraints present
18567 if Nkind (S) /= N_Subtype_Indication then
18569 Check_Incomplete (S);
18572 -- Ada 2005 (AI-231): Static check
18574 if Ada_Version >= Ada_2005
18575 and then Present (P)
18576 and then Null_Exclusion_Present (P)
18577 and then Nkind (P) /= N_Access_To_Object_Definition
18578 and then not Is_Access_Type (Entity (S))
18580 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
18583 -- The following is ugly, can't we have a range or even a flag???
18585 May_Have_Null_Exclusion :=
18586 Nkind_In (P, N_Access_Definition,
18587 N_Access_Function_Definition,
18588 N_Access_Procedure_Definition,
18589 N_Access_To_Object_Definition,
18591 N_Component_Definition)
18593 Nkind_In (P, N_Derived_Type_Definition,
18594 N_Discriminant_Specification,
18595 N_Formal_Object_Declaration,
18596 N_Object_Declaration,
18597 N_Object_Renaming_Declaration,
18598 N_Parameter_Specification,
18599 N_Subtype_Declaration);
18601 -- Create an Itype that is a duplicate of Entity (S) but with the
18602 -- null-exclusion attribute.
18604 if May_Have_Null_Exclusion
18605 and then Is_Access_Type (Entity (S))
18606 and then Null_Exclusion_Present (P)
18608 -- No need to check the case of an access to object definition.
18609 -- It is correct to define double not-null pointers.
18612 -- type Not_Null_Int_Ptr is not null access Integer;
18613 -- type Acc is not null access Not_Null_Int_Ptr;
18615 and then Nkind (P) /= N_Access_To_Object_Definition
18617 if Can_Never_Be_Null (Entity (S)) then
18618 case Nkind (Related_Nod) is
18619 when N_Full_Type_Declaration =>
18620 if Nkind (Type_Definition (Related_Nod))
18621 in N_Array_Type_Definition
18625 (Component_Definition
18626 (Type_Definition (Related_Nod)));
18629 Subtype_Indication (Type_Definition (Related_Nod));
18632 when N_Subtype_Declaration =>
18633 Error_Node := Subtype_Indication (Related_Nod);
18635 when N_Object_Declaration =>
18636 Error_Node := Object_Definition (Related_Nod);
18638 when N_Component_Declaration =>
18640 Subtype_Indication (Component_Definition (Related_Nod));
18642 when N_Allocator =>
18643 Error_Node := Expression (Related_Nod);
18646 pragma Assert (False);
18647 Error_Node := Related_Nod;
18651 ("`NOT NULL` not allowed (& already excludes null)",
18657 Create_Null_Excluding_Itype
18659 Related_Nod => P));
18660 Set_Entity (S, Etype (S));
18665 -- Case of constraint present, so that we have an N_Subtype_Indication
18666 -- node (this node is created only if constraints are present).
18669 Find_Type (Subtype_Mark (S));
18671 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
18673 (Nkind (Parent (S)) = N_Subtype_Declaration
18674 and then Is_Itype (Defining_Identifier (Parent (S))))
18676 Check_Incomplete (Subtype_Mark (S));
18680 Subtype_Mark_Id := Entity (Subtype_Mark (S));
18682 -- Explicit subtype declaration case
18684 if Nkind (P) = N_Subtype_Declaration then
18685 Def_Id := Defining_Identifier (P);
18687 -- Explicit derived type definition case
18689 elsif Nkind (P) = N_Derived_Type_Definition then
18690 Def_Id := Defining_Identifier (Parent (P));
18692 -- Implicit case, the Def_Id must be created as an implicit type.
18693 -- The one exception arises in the case of concurrent types, array
18694 -- and access types, where other subsidiary implicit types may be
18695 -- created and must appear before the main implicit type. In these
18696 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
18697 -- has not yet been called to create Def_Id.
18700 if Is_Array_Type (Subtype_Mark_Id)
18701 or else Is_Concurrent_Type (Subtype_Mark_Id)
18702 or else Is_Access_Type (Subtype_Mark_Id)
18706 -- For the other cases, we create a new unattached Itype,
18707 -- and set the indication to ensure it gets attached later.
18711 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
18715 -- If the kind of constraint is invalid for this kind of type,
18716 -- then give an error, and then pretend no constraint was given.
18718 if not Is_Valid_Constraint_Kind
18719 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
18722 ("incorrect constraint for this kind of type", Constraint (S));
18724 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
18726 -- Set Ekind of orphan itype, to prevent cascaded errors
18728 if Present (Def_Id) then
18729 Set_Ekind (Def_Id, Ekind (Any_Type));
18732 -- Make recursive call, having got rid of the bogus constraint
18734 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
18737 -- Remaining processing depends on type. Select on Base_Type kind to
18738 -- ensure getting to the concrete type kind in the case of a private
18739 -- subtype (needed when only doing semantic analysis).
18741 case Ekind (Base_Type (Subtype_Mark_Id)) is
18742 when Access_Kind =>
18743 Constrain_Access (Def_Id, S, Related_Nod);
18746 and then Is_Itype (Designated_Type (Def_Id))
18747 and then Nkind (Related_Nod) = N_Subtype_Declaration
18748 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
18750 Build_Itype_Reference
18751 (Designated_Type (Def_Id), Related_Nod);
18755 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
18757 when Decimal_Fixed_Point_Kind =>
18758 Constrain_Decimal (Def_Id, S);
18760 when Enumeration_Kind =>
18761 Constrain_Enumeration (Def_Id, S);
18763 when Ordinary_Fixed_Point_Kind =>
18764 Constrain_Ordinary_Fixed (Def_Id, S);
18767 Constrain_Float (Def_Id, S);
18769 when Integer_Kind =>
18770 Constrain_Integer (Def_Id, S);
18772 when E_Record_Type |
18775 E_Incomplete_Type =>
18776 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
18778 if Ekind (Def_Id) = E_Incomplete_Type then
18779 Set_Private_Dependents (Def_Id, New_Elmt_List);
18782 when Private_Kind =>
18783 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
18784 Set_Private_Dependents (Def_Id, New_Elmt_List);
18786 -- In case of an invalid constraint prevent further processing
18787 -- since the type constructed is missing expected fields.
18789 if Etype (Def_Id) = Any_Type then
18793 -- If the full view is that of a task with discriminants,
18794 -- we must constrain both the concurrent type and its
18795 -- corresponding record type. Otherwise we will just propagate
18796 -- the constraint to the full view, if available.
18798 if Present (Full_View (Subtype_Mark_Id))
18799 and then Has_Discriminants (Subtype_Mark_Id)
18800 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
18803 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
18805 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
18806 Constrain_Concurrent (Full_View_Id, S,
18807 Related_Nod, Related_Id, Suffix);
18808 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
18809 Set_Full_View (Def_Id, Full_View_Id);
18811 -- Introduce an explicit reference to the private subtype,
18812 -- to prevent scope anomalies in gigi if first use appears
18813 -- in a nested context, e.g. a later function body.
18814 -- Should this be generated in other contexts than a full
18815 -- type declaration?
18817 if Is_Itype (Def_Id)
18819 Nkind (Parent (P)) = N_Full_Type_Declaration
18821 Build_Itype_Reference (Def_Id, Parent (P));
18825 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
18828 when Concurrent_Kind =>
18829 Constrain_Concurrent (Def_Id, S,
18830 Related_Nod, Related_Id, Suffix);
18833 Error_Msg_N ("invalid subtype mark in subtype indication", S);
18836 -- Size and Convention are always inherited from the base type
18838 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
18839 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
18843 end Process_Subtype;
18845 ---------------------------------------
18846 -- Check_Anonymous_Access_Components --
18847 ---------------------------------------
18849 procedure Check_Anonymous_Access_Components
18850 (Typ_Decl : Node_Id;
18853 Comp_List : Node_Id)
18855 Loc : constant Source_Ptr := Sloc (Typ_Decl);
18856 Anon_Access : Entity_Id;
18859 Comp_Def : Node_Id;
18861 Type_Def : Node_Id;
18863 procedure Build_Incomplete_Type_Declaration;
18864 -- If the record type contains components that include an access to the
18865 -- current record, then create an incomplete type declaration for the
18866 -- record, to be used as the designated type of the anonymous access.
18867 -- This is done only once, and only if there is no previous partial
18868 -- view of the type.
18870 function Designates_T (Subt : Node_Id) return Boolean;
18871 -- Check whether a node designates the enclosing record type, or 'Class
18874 function Mentions_T (Acc_Def : Node_Id) return Boolean;
18875 -- Check whether an access definition includes a reference to
18876 -- the enclosing record type. The reference can be a subtype mark
18877 -- in the access definition itself, a 'Class attribute reference, or
18878 -- recursively a reference appearing in a parameter specification
18879 -- or result definition of an access_to_subprogram definition.
18881 --------------------------------------
18882 -- Build_Incomplete_Type_Declaration --
18883 --------------------------------------
18885 procedure Build_Incomplete_Type_Declaration is
18890 -- Is_Tagged indicates whether the type is tagged. It is tagged if
18891 -- it's "is new ... with record" or else "is tagged record ...".
18893 Is_Tagged : constant Boolean :=
18894 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
18897 (Record_Extension_Part (Type_Definition (Typ_Decl))))
18899 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
18900 and then Tagged_Present (Type_Definition (Typ_Decl)));
18903 -- If there is a previous partial view, no need to create a new one
18904 -- If the partial view, given by Prev, is incomplete, If Prev is
18905 -- a private declaration, full declaration is flagged accordingly.
18907 if Prev /= Typ then
18909 Make_Class_Wide_Type (Prev);
18910 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
18911 Set_Etype (Class_Wide_Type (Typ), Typ);
18916 elsif Has_Private_Declaration (Typ) then
18918 -- If we refer to T'Class inside T, and T is the completion of a
18919 -- private type, then we need to make sure the class-wide type
18923 Make_Class_Wide_Type (Typ);
18928 -- If there was a previous anonymous access type, the incomplete
18929 -- type declaration will have been created already.
18931 elsif Present (Current_Entity (Typ))
18932 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
18933 and then Full_View (Current_Entity (Typ)) = Typ
18936 and then Comes_From_Source (Current_Entity (Typ))
18937 and then not Is_Tagged_Type (Current_Entity (Typ))
18939 Make_Class_Wide_Type (Typ);
18941 ("incomplete view of tagged type should be declared tagged?",
18942 Parent (Current_Entity (Typ)));
18947 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
18948 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
18950 -- Type has already been inserted into the current scope. Remove
18951 -- it, and add incomplete declaration for type, so that subsequent
18952 -- anonymous access types can use it. The entity is unchained from
18953 -- the homonym list and from immediate visibility. After analysis,
18954 -- the entity in the incomplete declaration becomes immediately
18955 -- visible in the record declaration that follows.
18957 H := Current_Entity (Typ);
18960 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
18963 and then Homonym (H) /= Typ
18965 H := Homonym (Typ);
18968 Set_Homonym (H, Homonym (Typ));
18971 Insert_Before (Typ_Decl, Decl);
18973 Set_Full_View (Inc_T, Typ);
18977 -- Create a common class-wide type for both views, and set the
18978 -- Etype of the class-wide type to the full view.
18980 Make_Class_Wide_Type (Inc_T);
18981 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
18982 Set_Etype (Class_Wide_Type (Typ), Typ);
18985 end Build_Incomplete_Type_Declaration;
18991 function Designates_T (Subt : Node_Id) return Boolean is
18992 Type_Id : constant Name_Id := Chars (Typ);
18994 function Names_T (Nam : Node_Id) return Boolean;
18995 -- The record type has not been introduced in the current scope
18996 -- yet, so we must examine the name of the type itself, either
18997 -- an identifier T, or an expanded name of the form P.T, where
18998 -- P denotes the current scope.
19004 function Names_T (Nam : Node_Id) return Boolean is
19006 if Nkind (Nam) = N_Identifier then
19007 return Chars (Nam) = Type_Id;
19009 elsif Nkind (Nam) = N_Selected_Component then
19010 if Chars (Selector_Name (Nam)) = Type_Id then
19011 if Nkind (Prefix (Nam)) = N_Identifier then
19012 return Chars (Prefix (Nam)) = Chars (Current_Scope);
19014 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
19015 return Chars (Selector_Name (Prefix (Nam))) =
19016 Chars (Current_Scope);
19030 -- Start of processing for Designates_T
19033 if Nkind (Subt) = N_Identifier then
19034 return Chars (Subt) = Type_Id;
19036 -- Reference can be through an expanded name which has not been
19037 -- analyzed yet, and which designates enclosing scopes.
19039 elsif Nkind (Subt) = N_Selected_Component then
19040 if Names_T (Subt) then
19043 -- Otherwise it must denote an entity that is already visible.
19044 -- The access definition may name a subtype of the enclosing
19045 -- type, if there is a previous incomplete declaration for it.
19048 Find_Selected_Component (Subt);
19050 Is_Entity_Name (Subt)
19051 and then Scope (Entity (Subt)) = Current_Scope
19053 (Chars (Base_Type (Entity (Subt))) = Type_Id
19055 (Is_Class_Wide_Type (Entity (Subt))
19057 Chars (Etype (Base_Type (Entity (Subt)))) =
19061 -- A reference to the current type may appear as the prefix of
19062 -- a 'Class attribute.
19064 elsif Nkind (Subt) = N_Attribute_Reference
19065 and then Attribute_Name (Subt) = Name_Class
19067 return Names_T (Prefix (Subt));
19078 function Mentions_T (Acc_Def : Node_Id) return Boolean is
19079 Param_Spec : Node_Id;
19081 Acc_Subprg : constant Node_Id :=
19082 Access_To_Subprogram_Definition (Acc_Def);
19085 if No (Acc_Subprg) then
19086 return Designates_T (Subtype_Mark (Acc_Def));
19089 -- Component is an access_to_subprogram: examine its formals,
19090 -- and result definition in the case of an access_to_function.
19092 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
19093 while Present (Param_Spec) loop
19094 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
19095 and then Mentions_T (Parameter_Type (Param_Spec))
19099 elsif Designates_T (Parameter_Type (Param_Spec)) then
19106 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
19107 if Nkind (Result_Definition (Acc_Subprg)) =
19108 N_Access_Definition
19110 return Mentions_T (Result_Definition (Acc_Subprg));
19112 return Designates_T (Result_Definition (Acc_Subprg));
19119 -- Start of processing for Check_Anonymous_Access_Components
19122 if No (Comp_List) then
19126 Comp := First (Component_Items (Comp_List));
19127 while Present (Comp) loop
19128 if Nkind (Comp) = N_Component_Declaration
19130 (Access_Definition (Component_Definition (Comp)))
19132 Mentions_T (Access_Definition (Component_Definition (Comp)))
19134 Comp_Def := Component_Definition (Comp);
19136 Access_To_Subprogram_Definition
19137 (Access_Definition (Comp_Def));
19139 Build_Incomplete_Type_Declaration;
19140 Anon_Access := Make_Temporary (Loc, 'S');
19142 -- Create a declaration for the anonymous access type: either
19143 -- an access_to_object or an access_to_subprogram.
19145 if Present (Acc_Def) then
19146 if Nkind (Acc_Def) = N_Access_Function_Definition then
19148 Make_Access_Function_Definition (Loc,
19149 Parameter_Specifications =>
19150 Parameter_Specifications (Acc_Def),
19151 Result_Definition => Result_Definition (Acc_Def));
19154 Make_Access_Procedure_Definition (Loc,
19155 Parameter_Specifications =>
19156 Parameter_Specifications (Acc_Def));
19161 Make_Access_To_Object_Definition (Loc,
19162 Subtype_Indication =>
19165 (Access_Definition (Comp_Def))));
19167 Set_Constant_Present
19168 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
19170 (Type_Def, All_Present (Access_Definition (Comp_Def)));
19173 Set_Null_Exclusion_Present
19175 Null_Exclusion_Present (Access_Definition (Comp_Def)));
19178 Make_Full_Type_Declaration (Loc,
19179 Defining_Identifier => Anon_Access,
19180 Type_Definition => Type_Def);
19182 Insert_Before (Typ_Decl, Decl);
19185 -- If an access to subprogram, create the extra formals
19187 if Present (Acc_Def) then
19188 Create_Extra_Formals (Designated_Type (Anon_Access));
19190 -- If an access to object, preserve entity of designated type,
19191 -- for ASIS use, before rewriting the component definition.
19198 Desig := Entity (Subtype_Indication (Type_Def));
19200 -- If the access definition is to the current record,
19201 -- the visible entity at this point is an incomplete
19202 -- type. Retrieve the full view to simplify ASIS queries
19204 if Ekind (Desig) = E_Incomplete_Type then
19205 Desig := Full_View (Desig);
19209 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
19214 Make_Component_Definition (Loc,
19215 Subtype_Indication =>
19216 New_Occurrence_Of (Anon_Access, Loc)));
19218 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
19219 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
19221 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
19224 Set_Is_Local_Anonymous_Access (Anon_Access);
19230 if Present (Variant_Part (Comp_List)) then
19234 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
19235 while Present (V) loop
19236 Check_Anonymous_Access_Components
19237 (Typ_Decl, Typ, Prev, Component_List (V));
19238 Next_Non_Pragma (V);
19242 end Check_Anonymous_Access_Components;
19244 --------------------------------
19245 -- Preanalyze_Spec_Expression --
19246 --------------------------------
19248 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
19249 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
19251 In_Spec_Expression := True;
19252 Preanalyze_And_Resolve (N, T);
19253 In_Spec_Expression := Save_In_Spec_Expression;
19254 end Preanalyze_Spec_Expression;
19256 -----------------------------
19257 -- Record_Type_Declaration --
19258 -----------------------------
19260 procedure Record_Type_Declaration
19265 Def : constant Node_Id := Type_Definition (N);
19266 Is_Tagged : Boolean;
19267 Tag_Comp : Entity_Id;
19270 -- These flags must be initialized before calling Process_Discriminants
19271 -- because this routine makes use of them.
19273 Set_Ekind (T, E_Record_Type);
19275 Init_Size_Align (T);
19276 Set_Interfaces (T, No_Elist);
19277 Set_Stored_Constraint (T, No_Elist);
19281 if Ada_Version < Ada_2005
19282 or else not Interface_Present (Def)
19284 if Limited_Present (Def) then
19285 Check_SPARK_Restriction ("limited is not allowed", N);
19288 if Abstract_Present (Def) then
19289 Check_SPARK_Restriction ("abstract is not allowed", N);
19292 -- The flag Is_Tagged_Type might have already been set by
19293 -- Find_Type_Name if it detected an error for declaration T. This
19294 -- arises in the case of private tagged types where the full view
19295 -- omits the word tagged.
19298 Tagged_Present (Def)
19299 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
19301 Set_Is_Tagged_Type (T, Is_Tagged);
19302 Set_Is_Limited_Record (T, Limited_Present (Def));
19304 -- Type is abstract if full declaration carries keyword, or if
19305 -- previous partial view did.
19307 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
19308 or else Abstract_Present (Def));
19311 Check_SPARK_Restriction ("interface is not allowed", N);
19314 Analyze_Interface_Declaration (T, Def);
19316 if Present (Discriminant_Specifications (N)) then
19318 ("interface types cannot have discriminants",
19319 Defining_Identifier
19320 (First (Discriminant_Specifications (N))));
19324 -- First pass: if there are self-referential access components,
19325 -- create the required anonymous access type declarations, and if
19326 -- need be an incomplete type declaration for T itself.
19328 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
19330 if Ada_Version >= Ada_2005
19331 and then Present (Interface_List (Def))
19333 Check_Interfaces (N, Def);
19336 Ifaces_List : Elist_Id;
19339 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
19340 -- already in the parents.
19344 Ifaces_List => Ifaces_List,
19345 Exclude_Parents => True);
19347 Set_Interfaces (T, Ifaces_List);
19351 -- Records constitute a scope for the component declarations within.
19352 -- The scope is created prior to the processing of these declarations.
19353 -- Discriminants are processed first, so that they are visible when
19354 -- processing the other components. The Ekind of the record type itself
19355 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
19357 -- Enter record scope
19361 -- If an incomplete or private type declaration was already given for
19362 -- the type, then this scope already exists, and the discriminants have
19363 -- been declared within. We must verify that the full declaration
19364 -- matches the incomplete one.
19366 Check_Or_Process_Discriminants (N, T, Prev);
19368 Set_Is_Constrained (T, not Has_Discriminants (T));
19369 Set_Has_Delayed_Freeze (T, True);
19371 -- For tagged types add a manually analyzed component corresponding
19372 -- to the component _tag, the corresponding piece of tree will be
19373 -- expanded as part of the freezing actions if it is not a CPP_Class.
19377 -- Do not add the tag unless we are in expansion mode
19379 if Expander_Active then
19380 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
19381 Enter_Name (Tag_Comp);
19383 Set_Ekind (Tag_Comp, E_Component);
19384 Set_Is_Tag (Tag_Comp);
19385 Set_Is_Aliased (Tag_Comp);
19386 Set_Etype (Tag_Comp, RTE (RE_Tag));
19387 Set_DT_Entry_Count (Tag_Comp, No_Uint);
19388 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
19389 Init_Component_Location (Tag_Comp);
19391 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
19392 -- implemented interfaces.
19394 if Has_Interfaces (T) then
19395 Add_Interface_Tag_Components (N, T);
19399 Make_Class_Wide_Type (T);
19400 Set_Direct_Primitive_Operations (T, New_Elmt_List);
19403 -- We must suppress range checks when processing record components in
19404 -- the presence of discriminants, since we don't want spurious checks to
19405 -- be generated during their analysis, but Suppress_Range_Checks flags
19406 -- must be reset the after processing the record definition.
19408 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
19409 -- couldn't we just use the normal range check suppression method here.
19410 -- That would seem cleaner ???
19412 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
19413 Set_Kill_Range_Checks (T, True);
19414 Record_Type_Definition (Def, Prev);
19415 Set_Kill_Range_Checks (T, False);
19417 Record_Type_Definition (Def, Prev);
19420 -- Exit from record scope
19424 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
19425 -- the implemented interfaces and associate them an aliased entity.
19428 and then not Is_Empty_List (Interface_List (Def))
19430 Derive_Progenitor_Subprograms (T, T);
19432 end Record_Type_Declaration;
19434 ----------------------------
19435 -- Record_Type_Definition --
19436 ----------------------------
19438 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
19439 Component : Entity_Id;
19440 Ctrl_Components : Boolean := False;
19441 Final_Storage_Only : Boolean;
19445 if Ekind (Prev_T) = E_Incomplete_Type then
19446 T := Full_View (Prev_T);
19451 -- In SPARK, tagged types and type extensions may only be declared in
19452 -- the specification of library unit packages.
19454 if Present (Def) and then Is_Tagged_Type (T) then
19460 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
19461 Typ := Parent (Def);
19464 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
19465 Typ := Parent (Parent (Def));
19468 Ctxt := Parent (Typ);
19470 if Nkind (Ctxt) = N_Package_Body
19471 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
19473 Check_SPARK_Restriction
19474 ("type should be defined in package specification", Typ);
19476 elsif Nkind (Ctxt) /= N_Package_Specification
19477 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
19479 Check_SPARK_Restriction
19480 ("type should be defined in library unit package", Typ);
19485 Final_Storage_Only := not Is_Controlled (T);
19487 -- Ada 2005: check whether an explicit Limited is present in a derived
19488 -- type declaration.
19490 if Nkind (Parent (Def)) = N_Derived_Type_Definition
19491 and then Limited_Present (Parent (Def))
19493 Set_Is_Limited_Record (T);
19496 -- If the component list of a record type is defined by the reserved
19497 -- word null and there is no discriminant part, then the record type has
19498 -- no components and all records of the type are null records (RM 3.7)
19499 -- This procedure is also called to process the extension part of a
19500 -- record extension, in which case the current scope may have inherited
19504 or else No (Component_List (Def))
19505 or else Null_Present (Component_List (Def))
19507 if not Is_Tagged_Type (T) then
19508 Check_SPARK_Restriction ("non-tagged record cannot be null", Def);
19512 Analyze_Declarations (Component_Items (Component_List (Def)));
19514 if Present (Variant_Part (Component_List (Def))) then
19515 Check_SPARK_Restriction ("variant part is not allowed", Def);
19516 Analyze (Variant_Part (Component_List (Def)));
19520 -- After completing the semantic analysis of the record definition,
19521 -- record components, both new and inherited, are accessible. Set their
19522 -- kind accordingly. Exclude malformed itypes from illegal declarations,
19523 -- whose Ekind may be void.
19525 Component := First_Entity (Current_Scope);
19526 while Present (Component) loop
19527 if Ekind (Component) = E_Void
19528 and then not Is_Itype (Component)
19530 Set_Ekind (Component, E_Component);
19531 Init_Component_Location (Component);
19534 if Has_Task (Etype (Component)) then
19538 if Ekind (Component) /= E_Component then
19541 -- Do not set Has_Controlled_Component on a class-wide equivalent
19542 -- type. See Make_CW_Equivalent_Type.
19544 elsif not Is_Class_Wide_Equivalent_Type (T)
19545 and then (Has_Controlled_Component (Etype (Component))
19546 or else (Chars (Component) /= Name_uParent
19547 and then Is_Controlled (Etype (Component))))
19549 Set_Has_Controlled_Component (T, True);
19550 Final_Storage_Only :=
19552 and then Finalize_Storage_Only (Etype (Component));
19553 Ctrl_Components := True;
19556 Next_Entity (Component);
19559 -- A Type is Finalize_Storage_Only only if all its controlled components
19562 if Ctrl_Components then
19563 Set_Finalize_Storage_Only (T, Final_Storage_Only);
19566 -- Place reference to end record on the proper entity, which may
19567 -- be a partial view.
19569 if Present (Def) then
19570 Process_End_Label (Def, 'e', Prev_T);
19572 end Record_Type_Definition;
19574 ------------------------
19575 -- Replace_Components --
19576 ------------------------
19578 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
19579 function Process (N : Node_Id) return Traverse_Result;
19585 function Process (N : Node_Id) return Traverse_Result is
19589 if Nkind (N) = N_Discriminant_Specification then
19590 Comp := First_Discriminant (Typ);
19591 while Present (Comp) loop
19592 if Chars (Comp) = Chars (Defining_Identifier (N)) then
19593 Set_Defining_Identifier (N, Comp);
19597 Next_Discriminant (Comp);
19600 elsif Nkind (N) = N_Component_Declaration then
19601 Comp := First_Component (Typ);
19602 while Present (Comp) loop
19603 if Chars (Comp) = Chars (Defining_Identifier (N)) then
19604 Set_Defining_Identifier (N, Comp);
19608 Next_Component (Comp);
19615 procedure Replace is new Traverse_Proc (Process);
19617 -- Start of processing for Replace_Components
19621 end Replace_Components;
19623 -------------------------------
19624 -- Set_Completion_Referenced --
19625 -------------------------------
19627 procedure Set_Completion_Referenced (E : Entity_Id) is
19629 -- If in main unit, mark entity that is a completion as referenced,
19630 -- warnings go on the partial view when needed.
19632 if In_Extended_Main_Source_Unit (E) then
19633 Set_Referenced (E);
19635 end Set_Completion_Referenced;
19637 ---------------------
19638 -- Set_Fixed_Range --
19639 ---------------------
19641 -- The range for fixed-point types is complicated by the fact that we
19642 -- do not know the exact end points at the time of the declaration. This
19643 -- is true for three reasons:
19645 -- A size clause may affect the fudging of the end-points.
19646 -- A small clause may affect the values of the end-points.
19647 -- We try to include the end-points if it does not affect the size.
19649 -- This means that the actual end-points must be established at the
19650 -- point when the type is frozen. Meanwhile, we first narrow the range
19651 -- as permitted (so that it will fit if necessary in a small specified
19652 -- size), and then build a range subtree with these narrowed bounds.
19653 -- Set_Fixed_Range constructs the range from real literal values, and
19654 -- sets the range as the Scalar_Range of the given fixed-point type entity.
19656 -- The parent of this range is set to point to the entity so that it is
19657 -- properly hooked into the tree (unlike normal Scalar_Range entries for
19658 -- other scalar types, which are just pointers to the range in the
19659 -- original tree, this would otherwise be an orphan).
19661 -- The tree is left unanalyzed. When the type is frozen, the processing
19662 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
19663 -- analyzed, and uses this as an indication that it should complete
19664 -- work on the range (it will know the final small and size values).
19666 procedure Set_Fixed_Range
19672 S : constant Node_Id :=
19674 Low_Bound => Make_Real_Literal (Loc, Lo),
19675 High_Bound => Make_Real_Literal (Loc, Hi));
19677 Set_Scalar_Range (E, S);
19680 -- Before the freeze point, the bounds of a fixed point are universal
19681 -- and carry the corresponding type.
19683 Set_Etype (Low_Bound (S), Universal_Real);
19684 Set_Etype (High_Bound (S), Universal_Real);
19685 end Set_Fixed_Range;
19687 ----------------------------------
19688 -- Set_Scalar_Range_For_Subtype --
19689 ----------------------------------
19691 procedure Set_Scalar_Range_For_Subtype
19692 (Def_Id : Entity_Id;
19696 Kind : constant Entity_Kind := Ekind (Def_Id);
19699 -- Defend against previous error
19701 if Nkind (R) = N_Error then
19705 Set_Scalar_Range (Def_Id, R);
19707 -- We need to link the range into the tree before resolving it so
19708 -- that types that are referenced, including importantly the subtype
19709 -- itself, are properly frozen (Freeze_Expression requires that the
19710 -- expression be properly linked into the tree). Of course if it is
19711 -- already linked in, then we do not disturb the current link.
19713 if No (Parent (R)) then
19714 Set_Parent (R, Def_Id);
19717 -- Reset the kind of the subtype during analysis of the range, to
19718 -- catch possible premature use in the bounds themselves.
19720 Set_Ekind (Def_Id, E_Void);
19721 Process_Range_Expr_In_Decl (R, Subt);
19722 Set_Ekind (Def_Id, Kind);
19723 end Set_Scalar_Range_For_Subtype;
19725 --------------------------------------------------------
19726 -- Set_Stored_Constraint_From_Discriminant_Constraint --
19727 --------------------------------------------------------
19729 procedure Set_Stored_Constraint_From_Discriminant_Constraint
19733 -- Make sure set if encountered during Expand_To_Stored_Constraint
19735 Set_Stored_Constraint (E, No_Elist);
19737 -- Give it the right value
19739 if Is_Constrained (E) and then Has_Discriminants (E) then
19740 Set_Stored_Constraint (E,
19741 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
19743 end Set_Stored_Constraint_From_Discriminant_Constraint;
19745 -------------------------------------
19746 -- Signed_Integer_Type_Declaration --
19747 -------------------------------------
19749 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
19750 Implicit_Base : Entity_Id;
19751 Base_Typ : Entity_Id;
19754 Errs : Boolean := False;
19758 function Can_Derive_From (E : Entity_Id) return Boolean;
19759 -- Determine whether given bounds allow derivation from specified type
19761 procedure Check_Bound (Expr : Node_Id);
19762 -- Check bound to make sure it is integral and static. If not, post
19763 -- appropriate error message and set Errs flag
19765 ---------------------
19766 -- Can_Derive_From --
19767 ---------------------
19769 -- Note we check both bounds against both end values, to deal with
19770 -- strange types like ones with a range of 0 .. -12341234.
19772 function Can_Derive_From (E : Entity_Id) return Boolean is
19773 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
19774 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
19776 return Lo <= Lo_Val and then Lo_Val <= Hi
19778 Lo <= Hi_Val and then Hi_Val <= Hi;
19779 end Can_Derive_From;
19785 procedure Check_Bound (Expr : Node_Id) is
19787 -- If a range constraint is used as an integer type definition, each
19788 -- bound of the range must be defined by a static expression of some
19789 -- integer type, but the two bounds need not have the same integer
19790 -- type (Negative bounds are allowed.) (RM 3.5.4)
19792 if not Is_Integer_Type (Etype (Expr)) then
19794 ("integer type definition bounds must be of integer type", Expr);
19797 elsif not Is_OK_Static_Expression (Expr) then
19798 Flag_Non_Static_Expr
19799 ("non-static expression used for integer type bound!", Expr);
19802 -- The bounds are folded into literals, and we set their type to be
19803 -- universal, to avoid typing difficulties: we cannot set the type
19804 -- of the literal to the new type, because this would be a forward
19805 -- reference for the back end, and if the original type is user-
19806 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
19809 if Is_Entity_Name (Expr) then
19810 Fold_Uint (Expr, Expr_Value (Expr), True);
19813 Set_Etype (Expr, Universal_Integer);
19817 -- Start of processing for Signed_Integer_Type_Declaration
19820 -- Create an anonymous base type
19823 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
19825 -- Analyze and check the bounds, they can be of any integer type
19827 Lo := Low_Bound (Def);
19828 Hi := High_Bound (Def);
19830 -- Arbitrarily use Integer as the type if either bound had an error
19832 if Hi = Error or else Lo = Error then
19833 Base_Typ := Any_Integer;
19834 Set_Error_Posted (T, True);
19836 -- Here both bounds are OK expressions
19839 Analyze_And_Resolve (Lo, Any_Integer);
19840 Analyze_And_Resolve (Hi, Any_Integer);
19846 Hi := Type_High_Bound (Standard_Long_Long_Integer);
19847 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
19850 -- Find type to derive from
19852 Lo_Val := Expr_Value (Lo);
19853 Hi_Val := Expr_Value (Hi);
19855 if Can_Derive_From (Standard_Short_Short_Integer) then
19856 Base_Typ := Base_Type (Standard_Short_Short_Integer);
19858 elsif Can_Derive_From (Standard_Short_Integer) then
19859 Base_Typ := Base_Type (Standard_Short_Integer);
19861 elsif Can_Derive_From (Standard_Integer) then
19862 Base_Typ := Base_Type (Standard_Integer);
19864 elsif Can_Derive_From (Standard_Long_Integer) then
19865 Base_Typ := Base_Type (Standard_Long_Integer);
19867 elsif Can_Derive_From (Standard_Long_Long_Integer) then
19868 Base_Typ := Base_Type (Standard_Long_Long_Integer);
19871 Base_Typ := Base_Type (Standard_Long_Long_Integer);
19872 Error_Msg_N ("integer type definition bounds out of range", Def);
19873 Hi := Type_High_Bound (Standard_Long_Long_Integer);
19874 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
19878 -- Complete both implicit base and declared first subtype entities
19880 Set_Etype (Implicit_Base, Base_Typ);
19881 Set_Size_Info (Implicit_Base, (Base_Typ));
19882 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
19883 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
19885 Set_Ekind (T, E_Signed_Integer_Subtype);
19886 Set_Etype (T, Implicit_Base);
19888 -- In formal verification mode, restrict the base type's range to the
19889 -- minimum allowed by RM 3.5.4, namely the smallest symmetric range
19890 -- around zero with a possible extra negative value that contains the
19891 -- subtype range. Keep Size, RM_Size and First_Rep_Item info, which
19892 -- should not be relied upon in formal verification.
19894 if Strict_Alfa_Mode then
19898 Dloc : constant Source_Ptr := Sloc (Def);
19904 -- If the subtype range is empty, the smallest base type range
19905 -- is the symmetric range around zero containing Lo_Val and
19908 if UI_Gt (Lo_Val, Hi_Val) then
19909 Sym_Hi_Val := UI_Max (UI_Abs (Lo_Val), UI_Abs (Hi_Val));
19910 Sym_Lo_Val := UI_Negate (Sym_Hi_Val);
19912 -- Otherwise, if the subtype range is not empty and Hi_Val has
19913 -- the largest absolute value, Hi_Val is non negative and the
19914 -- smallest base type range is the symmetric range around zero
19915 -- containing Hi_Val.
19917 elsif UI_Le (UI_Abs (Lo_Val), UI_Abs (Hi_Val)) then
19918 Sym_Hi_Val := Hi_Val;
19919 Sym_Lo_Val := UI_Negate (Hi_Val);
19921 -- Otherwise, the subtype range is not empty, Lo_Val has the
19922 -- strictly largest absolute value, Lo_Val is negative and the
19923 -- smallest base type range is the symmetric range around zero
19924 -- with an extra negative value Lo_Val.
19927 Sym_Lo_Val := Lo_Val;
19928 Sym_Hi_Val := UI_Sub (UI_Negate (Lo_Val), Uint_1);
19931 Lbound := Make_Integer_Literal (Dloc, Sym_Lo_Val);
19932 Ubound := Make_Integer_Literal (Dloc, Sym_Hi_Val);
19933 Set_Is_Static_Expression (Lbound);
19934 Set_Is_Static_Expression (Ubound);
19935 Analyze_And_Resolve (Lbound, Any_Integer);
19936 Analyze_And_Resolve (Ubound, Any_Integer);
19938 Bounds := Make_Range (Dloc, Lbound, Ubound);
19939 Set_Etype (Bounds, Base_Typ);
19941 Set_Scalar_Range (Implicit_Base, Bounds);
19945 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
19948 Set_Size_Info (T, (Implicit_Base));
19949 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
19950 Set_Scalar_Range (T, Def);
19951 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
19952 Set_Is_Constrained (T);
19953 end Signed_Integer_Type_Declaration;