1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2009, 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_Res; use Sem_Res;
65 with Sem_Smem; use Sem_Smem;
66 with Sem_Type; use Sem_Type;
67 with Sem_Util; use Sem_Util;
68 with Sem_Warn; use Sem_Warn;
69 with Stand; use Stand;
70 with Sinfo; use Sinfo;
71 with Snames; use Snames;
72 with Targparm; use Targparm;
73 with Tbuild; use Tbuild;
74 with Ttypes; use Ttypes;
75 with Uintp; use Uintp;
76 with Urealp; use Urealp;
78 package body Sem_Ch3 is
80 -----------------------
81 -- Local Subprograms --
82 -----------------------
84 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
85 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
86 -- abstract interface types implemented by a record type or a derived
89 procedure Build_Derived_Type
91 Parent_Type : Entity_Id;
92 Derived_Type : Entity_Id;
93 Is_Completion : Boolean;
94 Derive_Subps : Boolean := True);
95 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
96 -- the N_Full_Type_Declaration node containing the derived type definition.
97 -- Parent_Type is the entity for the parent type in the derived type
98 -- definition and Derived_Type the actual derived type. Is_Completion must
99 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
100 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
101 -- completion of a private type declaration. If Is_Completion is set to
102 -- True, N is the completion of a private type declaration and Derived_Type
103 -- is different from the defining identifier inside N (i.e. Derived_Type /=
104 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
105 -- subprograms should be derived. The only case where this parameter is
106 -- False is when Build_Derived_Type is recursively called to process an
107 -- implicit derived full type for a type derived from a private type (in
108 -- that case the subprograms must only be derived for the private view of
111 -- ??? These flags need a bit of re-examination and re-documentation:
112 -- ??? are they both necessary (both seem related to the recursion)?
114 procedure Build_Derived_Access_Type
116 Parent_Type : Entity_Id;
117 Derived_Type : Entity_Id);
118 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
119 -- create an implicit base if the parent type is constrained or if the
120 -- subtype indication has a constraint.
122 procedure Build_Derived_Array_Type
124 Parent_Type : Entity_Id;
125 Derived_Type : Entity_Id);
126 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
127 -- create an implicit base if the parent type is constrained or if the
128 -- subtype indication has a constraint.
130 procedure Build_Derived_Concurrent_Type
132 Parent_Type : Entity_Id;
133 Derived_Type : Entity_Id);
134 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
135 -- protected type, inherit entries and protected subprograms, check
136 -- legality of discriminant constraints if any.
138 procedure Build_Derived_Enumeration_Type
140 Parent_Type : Entity_Id;
141 Derived_Type : Entity_Id);
142 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
143 -- type, we must create a new list of literals. Types derived from
144 -- Character and [Wide_]Wide_Character are special-cased.
146 procedure Build_Derived_Numeric_Type
148 Parent_Type : Entity_Id;
149 Derived_Type : Entity_Id);
150 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
151 -- an anonymous base type, and propagate constraint to subtype if needed.
153 procedure Build_Derived_Private_Type
155 Parent_Type : Entity_Id;
156 Derived_Type : Entity_Id;
157 Is_Completion : Boolean;
158 Derive_Subps : Boolean := True);
159 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
160 -- because the parent may or may not have a completion, and the derivation
161 -- may itself be a completion.
163 procedure Build_Derived_Record_Type
165 Parent_Type : Entity_Id;
166 Derived_Type : Entity_Id;
167 Derive_Subps : Boolean := True);
168 -- Subsidiary procedure for Build_Derived_Type and
169 -- Analyze_Private_Extension_Declaration used for tagged and untagged
170 -- record types. All parameters are as in Build_Derived_Type except that
171 -- N, in addition to being an N_Full_Type_Declaration node, can also be an
172 -- N_Private_Extension_Declaration node. See the definition of this routine
173 -- for much more info. Derive_Subps indicates whether subprograms should
174 -- be derived from the parent type. The only case where Derive_Subps is
175 -- False is for an implicit derived full type for a type derived from a
176 -- private type (see Build_Derived_Type).
178 procedure Build_Discriminal (Discrim : Entity_Id);
179 -- Create the discriminal corresponding to discriminant Discrim, that is
180 -- the parameter corresponding to Discrim to be used in initialization
181 -- procedures for the type where Discrim is a discriminant. Discriminals
182 -- are not used during semantic analysis, and are not fully defined
183 -- entities until expansion. Thus they are not given a scope until
184 -- initialization procedures are built.
186 function Build_Discriminant_Constraints
189 Derived_Def : Boolean := False) return Elist_Id;
190 -- Validate discriminant constraints and return the list of the constraints
191 -- in order of discriminant declarations, where T is the discriminated
192 -- unconstrained type. Def is the N_Subtype_Indication node where the
193 -- discriminants constraints for T are specified. Derived_Def is True
194 -- when building the discriminant constraints in a derived type definition
195 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
196 -- type and Def is the constraint "(xxx)" on T and this routine sets the
197 -- Corresponding_Discriminant field of the discriminants in the derived
198 -- type D to point to the corresponding discriminants in the parent type T.
200 procedure Build_Discriminated_Subtype
204 Related_Nod : Node_Id;
205 For_Access : Boolean := False);
206 -- Subsidiary procedure to Constrain_Discriminated_Type and to
207 -- Process_Incomplete_Dependents. Given
209 -- T (a possibly discriminated base type)
210 -- Def_Id (a very partially built subtype for T),
212 -- the call completes Def_Id to be the appropriate E_*_Subtype.
214 -- The Elist is the list of discriminant constraints if any (it is set
215 -- to No_Elist if T is not a discriminated type, and to an empty list if
216 -- T has discriminants but there are no discriminant constraints). The
217 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
218 -- The For_Access says whether or not this subtype is really constraining
219 -- an access type. That is its sole purpose is the designated type of an
220 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
221 -- is built to avoid freezing T when the access subtype is frozen.
223 function Build_Scalar_Bound
226 Der_T : Entity_Id) return Node_Id;
227 -- The bounds of a derived scalar type are conversions of the bounds of
228 -- the parent type. Optimize the representation if the bounds are literals.
229 -- Needs a more complete spec--what are the parameters exactly, and what
230 -- exactly is the returned value, and how is Bound affected???
232 procedure Build_Underlying_Full_View
236 -- If the completion of a private type is itself derived from a private
237 -- type, or if the full view of a private subtype is itself private, the
238 -- back-end has no way to compute the actual size of this type. We build
239 -- an internal subtype declaration of the proper parent type to convey
240 -- this information. This extra mechanism is needed because a full
241 -- view cannot itself have a full view (it would get clobbered during
244 procedure Check_Access_Discriminant_Requires_Limited
247 -- Check the restriction that the type to which an access discriminant
248 -- belongs must be a concurrent type or a descendant of a type with
249 -- the reserved word 'limited' in its declaration.
251 procedure Check_Anonymous_Access_Components
255 Comp_List : Node_Id);
256 -- Ada 2005 AI-382: an access component in a record definition can refer to
257 -- the enclosing record, in which case it denotes the type itself, and not
258 -- the current instance of the type. We create an anonymous access type for
259 -- the component, and flag it as an access to a component, so accessibility
260 -- checks are properly performed on it. The declaration of the access type
261 -- is placed ahead of that of the record to prevent order-of-elaboration
262 -- circularity issues in Gigi. We create an incomplete type for the record
263 -- declaration, which is the designated type of the anonymous access.
265 procedure Check_Delta_Expression (E : Node_Id);
266 -- Check that the expression represented by E is suitable for use as a
267 -- delta expression, i.e. it is of real type and is static.
269 procedure Check_Digits_Expression (E : Node_Id);
270 -- Check that the expression represented by E is suitable for use as a
271 -- digits expression, i.e. it is of integer type, positive and static.
273 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
274 -- Validate the initialization of an object declaration. T is the required
275 -- type, and Exp is the initialization expression.
277 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
278 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
280 procedure Check_Or_Process_Discriminants
283 Prev : Entity_Id := Empty);
284 -- If T is the full declaration of an incomplete or private type, check the
285 -- conformance of the discriminants, otherwise process them. Prev is the
286 -- entity of the partial declaration, if any.
288 procedure Check_Real_Bound (Bound : Node_Id);
289 -- Check given bound for being of real type and static. If not, post an
290 -- appropriate message, and rewrite the bound with the real literal zero.
292 procedure Constant_Redeclaration
296 -- Various checks on legality of full declaration of deferred constant.
297 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
298 -- node. The caller has not yet set any attributes of this entity.
300 function Contain_Interface
302 Ifaces : Elist_Id) return Boolean;
303 -- Ada 2005: Determine whether Iface is present in the list Ifaces
305 procedure Convert_Scalar_Bounds
307 Parent_Type : Entity_Id;
308 Derived_Type : Entity_Id;
310 -- For derived scalar types, convert the bounds in the type definition to
311 -- the derived type, and complete their analysis. Given a constraint of the
312 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
313 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
314 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
315 -- subtype are conversions of those bounds to the derived_type, so that
316 -- their typing is consistent.
318 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
319 -- Copies attributes from array base type T2 to array base type T1. Copies
320 -- only attributes that apply to base types, but not subtypes.
322 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
323 -- Copies attributes from array subtype T2 to array subtype T1. Copies
324 -- attributes that apply to both subtypes and base types.
326 procedure Create_Constrained_Components
330 Constraints : Elist_Id);
331 -- Build the list of entities for a constrained discriminated record
332 -- subtype. If a component depends on a discriminant, replace its subtype
333 -- using the discriminant values in the discriminant constraint. Subt
334 -- is the defining identifier for the subtype whose list of constrained
335 -- entities we will create. Decl_Node is the type declaration node where
336 -- we will attach all the itypes created. Typ is the base discriminated
337 -- type for the subtype Subt. Constraints is the list of discriminant
338 -- constraints for Typ.
340 function Constrain_Component_Type
342 Constrained_Typ : Entity_Id;
343 Related_Node : Node_Id;
345 Constraints : Elist_Id) return Entity_Id;
346 -- Given a discriminated base type Typ, a list of discriminant constraint
347 -- Constraints for Typ and a component of Typ, with type Compon_Type,
348 -- create and return the type corresponding to Compon_type where all
349 -- discriminant references are replaced with the corresponding constraint.
350 -- If no discriminant references occur in Compon_Typ then return it as is.
351 -- Constrained_Typ is the final constrained subtype to which the
352 -- constrained Compon_Type belongs. Related_Node is the node where we will
353 -- attach all the itypes created.
355 -- Above description is confused, what is Compon_Type???
357 procedure Constrain_Access
358 (Def_Id : in out Entity_Id;
360 Related_Nod : Node_Id);
361 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
362 -- an anonymous type created for a subtype indication. In that case it is
363 -- created in the procedure and attached to Related_Nod.
365 procedure Constrain_Array
366 (Def_Id : in out Entity_Id;
368 Related_Nod : Node_Id;
369 Related_Id : Entity_Id;
371 -- Apply a list of index constraints to an unconstrained array type. The
372 -- first parameter is the entity for the resulting subtype. A value of
373 -- Empty for Def_Id indicates that an implicit type must be created, but
374 -- creation is delayed (and must be done by this procedure) because other
375 -- subsidiary implicit types must be created first (which is why Def_Id
376 -- is an in/out parameter). The second parameter is a subtype indication
377 -- node for the constrained array to be created (e.g. something of the
378 -- form string (1 .. 10)). Related_Nod gives the place where this type
379 -- has to be inserted in the tree. The Related_Id and Suffix parameters
380 -- are used to build the associated Implicit type name.
382 procedure Constrain_Concurrent
383 (Def_Id : in out Entity_Id;
385 Related_Nod : Node_Id;
386 Related_Id : Entity_Id;
388 -- Apply list of discriminant constraints to an unconstrained concurrent
391 -- SI is the N_Subtype_Indication node containing the constraint and
392 -- the unconstrained type to constrain.
394 -- Def_Id is the entity for the resulting constrained subtype. A value
395 -- of Empty for Def_Id indicates that an implicit type must be created,
396 -- but creation is delayed (and must be done by this procedure) because
397 -- other subsidiary implicit types must be created first (which is why
398 -- Def_Id is an in/out parameter).
400 -- Related_Nod gives the place where this type has to be inserted
403 -- The last two arguments are used to create its external name if needed.
405 function Constrain_Corresponding_Record
406 (Prot_Subt : Entity_Id;
407 Corr_Rec : Entity_Id;
408 Related_Nod : Node_Id;
409 Related_Id : Entity_Id) return Entity_Id;
410 -- When constraining a protected type or task type with discriminants,
411 -- constrain the corresponding record with the same discriminant values.
413 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
414 -- Constrain a decimal fixed point type with a digits constraint and/or a
415 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
417 procedure Constrain_Discriminated_Type
420 Related_Nod : Node_Id;
421 For_Access : Boolean := False);
422 -- Process discriminant constraints of composite type. Verify that values
423 -- have been provided for all discriminants, that the original type is
424 -- unconstrained, and that the types of the supplied expressions match
425 -- the discriminant types. The first three parameters are like in routine
426 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
429 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
430 -- Constrain an enumeration type with a range constraint. This is identical
431 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
433 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
434 -- Constrain a floating point type with either a digits constraint
435 -- and/or a range constraint, building a E_Floating_Point_Subtype.
437 procedure Constrain_Index
440 Related_Nod : Node_Id;
441 Related_Id : Entity_Id;
444 -- Process an index constraint in a constrained array declaration. The
445 -- constraint can be a subtype name, or a range with or without an explicit
446 -- subtype mark. The index is the corresponding index of the unconstrained
447 -- array. The Related_Id and Suffix parameters are used to build the
448 -- associated Implicit type name.
450 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
451 -- Build subtype of a signed or modular integer type
453 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
454 -- Constrain an ordinary fixed point type with a range constraint, and
455 -- build an E_Ordinary_Fixed_Point_Subtype entity.
457 procedure Copy_And_Swap (Priv, Full : Entity_Id);
458 -- Copy the Priv entity into the entity of its full declaration then swap
459 -- the two entities in such a manner that the former private type is now
460 -- seen as a full type.
462 procedure Decimal_Fixed_Point_Type_Declaration
465 -- Create a new decimal fixed point type, and apply the constraint to
466 -- obtain a subtype of this new type.
468 procedure Complete_Private_Subtype
471 Full_Base : Entity_Id;
472 Related_Nod : Node_Id);
473 -- Complete the implicit full view of a private subtype by setting the
474 -- appropriate semantic fields. If the full view of the parent is a record
475 -- type, build constrained components of subtype.
477 procedure Derive_Progenitor_Subprograms
478 (Parent_Type : Entity_Id;
479 Tagged_Type : Entity_Id);
480 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
481 -- operations of progenitors of Tagged_Type, and replace the subsidiary
482 -- subtypes with Tagged_Type, to build the specs of the inherited interface
483 -- primitives. The derived primitives are aliased to those of the
484 -- interface. This routine takes care also of transferring to the full-view
485 -- subprograms associated with the partial-view of Tagged_Type that cover
486 -- interface primitives.
488 procedure Derived_Standard_Character
490 Parent_Type : Entity_Id;
491 Derived_Type : Entity_Id);
492 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
493 -- derivations from types Standard.Character and Standard.Wide_Character.
495 procedure Derived_Type_Declaration
498 Is_Completion : Boolean);
499 -- Process a derived type declaration. Build_Derived_Type is invoked
500 -- to process the actual derived type definition. Parameters N and
501 -- Is_Completion have the same meaning as in Build_Derived_Type.
502 -- T is the N_Defining_Identifier for the entity defined in the
503 -- N_Full_Type_Declaration node N, that is T is the derived type.
505 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
506 -- Insert each literal in symbol table, as an overloadable identifier. Each
507 -- enumeration type is mapped into a sequence of integers, and each literal
508 -- is defined as a constant with integer value. If any of the literals are
509 -- character literals, the type is a character type, which means that
510 -- strings are legal aggregates for arrays of components of the type.
512 function Expand_To_Stored_Constraint
514 Constraint : Elist_Id) return Elist_Id;
515 -- Given a constraint (i.e. a list of expressions) on the discriminants of
516 -- Typ, expand it into a constraint on the stored discriminants and return
517 -- the new list of expressions constraining the stored discriminants.
519 function Find_Type_Of_Object
521 Related_Nod : Node_Id) return Entity_Id;
522 -- Get type entity for object referenced by Obj_Def, attaching the
523 -- implicit types generated to Related_Nod
525 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
526 -- Create a new float and apply the constraint to obtain subtype of it
528 function Has_Range_Constraint (N : Node_Id) return Boolean;
529 -- Given an N_Subtype_Indication node N, return True if a range constraint
530 -- is present, either directly, or as part of a digits or delta constraint.
531 -- In addition, a digits constraint in the decimal case returns True, since
532 -- it establishes a default range if no explicit range is present.
534 function Inherit_Components
536 Parent_Base : Entity_Id;
537 Derived_Base : Entity_Id;
539 Inherit_Discr : Boolean;
540 Discs : Elist_Id) return Elist_Id;
541 -- Called from Build_Derived_Record_Type to inherit the components of
542 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
543 -- For more information on derived types and component inheritance please
544 -- consult the comment above the body of Build_Derived_Record_Type.
546 -- N is the original derived type declaration
548 -- Is_Tagged is set if we are dealing with tagged types
550 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
551 -- Parent_Base, otherwise no discriminants are inherited.
553 -- Discs gives the list of constraints that apply to Parent_Base in the
554 -- derived type declaration. If Discs is set to No_Elist, then we have
555 -- the following situation:
557 -- type Parent (D1..Dn : ..) is [tagged] record ...;
558 -- type Derived is new Parent [with ...];
560 -- which gets treated as
562 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
564 -- For untagged types the returned value is an association list. The list
565 -- starts from the association (Parent_Base => Derived_Base), and then it
566 -- contains a sequence of the associations of the form
568 -- (Old_Component => New_Component),
570 -- where Old_Component is the Entity_Id of a component in Parent_Base and
571 -- New_Component is the Entity_Id of the corresponding component in
572 -- Derived_Base. For untagged records, this association list is needed when
573 -- copying the record declaration for the derived base. In the tagged case
574 -- the value returned is irrelevant.
576 function Is_Progenitor
578 Typ : Entity_Id) return Boolean;
579 -- Determine whether the interface Iface is implemented by Typ. It requires
580 -- traversing the list of abstract interfaces of the type, as well as that
581 -- of the ancestor types. The predicate is used to determine when a formal
582 -- in the signature of an inherited operation must carry the derived type.
584 function Is_Valid_Constraint_Kind
586 Constraint_Kind : Node_Kind) return Boolean;
587 -- Returns True if it is legal to apply the given kind of constraint to the
588 -- given kind of type (index constraint to an array type, for example).
590 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
591 -- Create new modular type. Verify that modulus is in bounds and is
592 -- a power of two (implementation restriction).
594 procedure New_Concatenation_Op (Typ : Entity_Id);
595 -- Create an abbreviated declaration for an operator in order to
596 -- materialize concatenation on array types.
598 procedure Ordinary_Fixed_Point_Type_Declaration
601 -- Create a new ordinary fixed point type, and apply the constraint to
602 -- obtain subtype of it.
604 procedure Prepare_Private_Subtype_Completion
606 Related_Nod : Node_Id);
607 -- Id is a subtype of some private type. Creates the full declaration
608 -- associated with Id whenever possible, i.e. when the full declaration
609 -- of the base type is already known. Records each subtype into
610 -- Private_Dependents of the base type.
612 procedure Process_Incomplete_Dependents
616 -- Process all entities that depend on an incomplete type. There include
617 -- subtypes, subprogram types that mention the incomplete type in their
618 -- profiles, and subprogram with access parameters that designate the
621 -- Inc_T is the defining identifier of an incomplete type declaration, its
622 -- Ekind is E_Incomplete_Type.
624 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
626 -- Full_T is N's defining identifier.
628 -- Subtypes of incomplete types with discriminants are completed when the
629 -- parent type is. This is simpler than private subtypes, because they can
630 -- only appear in the same scope, and there is no need to exchange views.
631 -- Similarly, access_to_subprogram types may have a parameter or a return
632 -- type that is an incomplete type, and that must be replaced with the
635 -- If the full type is tagged, subprogram with access parameters that
636 -- designated the incomplete may be primitive operations of the full type,
637 -- and have to be processed accordingly.
639 procedure Process_Real_Range_Specification (Def : Node_Id);
640 -- Given the type definition for a real type, this procedure processes and
641 -- checks the real range specification of this type definition if one is
642 -- present. If errors are found, error messages are posted, and the
643 -- Real_Range_Specification of Def is reset to Empty.
645 procedure Record_Type_Declaration
649 -- Process a record type declaration (for both untagged and tagged
650 -- records). Parameters T and N are exactly like in procedure
651 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
652 -- for this routine. If this is the completion of an incomplete type
653 -- declaration, Prev is the entity of the incomplete declaration, used for
654 -- cross-referencing. Otherwise Prev = T.
656 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
657 -- This routine is used to process the actual record type definition (both
658 -- for untagged and tagged records). Def is a record type definition node.
659 -- This procedure analyzes the components in this record type definition.
660 -- Prev_T is the entity for the enclosing record type. It is provided so
661 -- that its Has_Task flag can be set if any of the component have Has_Task
662 -- set. If the declaration is the completion of an incomplete type
663 -- declaration, Prev_T is the original incomplete type, whose full view is
666 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
667 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
668 -- build a copy of the declaration tree of the parent, and we create
669 -- independently the list of components for the derived type. Semantic
670 -- information uses the component entities, but record representation
671 -- clauses are validated on the declaration tree. This procedure replaces
672 -- discriminants and components in the declaration with those that have
673 -- been created by Inherit_Components.
675 procedure Set_Fixed_Range
680 -- Build a range node with the given bounds and set it as the Scalar_Range
681 -- of the given fixed-point type entity. Loc is the source location used
682 -- for the constructed range. See body for further details.
684 procedure Set_Scalar_Range_For_Subtype
688 -- This routine is used to set the scalar range field for a subtype given
689 -- Def_Id, the entity for the subtype, and R, the range expression for the
690 -- scalar range. Subt provides the parent subtype to be used to analyze,
691 -- resolve, and check the given range.
693 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
694 -- Create a new signed integer entity, and apply the constraint to obtain
695 -- the required first named subtype of this type.
697 procedure Set_Stored_Constraint_From_Discriminant_Constraint
699 -- E is some record type. This routine computes E's Stored_Constraint
700 -- from its Discriminant_Constraint.
702 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
703 -- Check that an entity in a list of progenitors is an interface,
704 -- emit error otherwise.
706 -----------------------
707 -- Access_Definition --
708 -----------------------
710 function Access_Definition
711 (Related_Nod : Node_Id;
712 N : Node_Id) return Entity_Id
714 Loc : constant Source_Ptr := Sloc (Related_Nod);
715 Anon_Type : Entity_Id;
716 Anon_Scope : Entity_Id;
717 Desig_Type : Entity_Id;
719 Enclosing_Prot_Type : Entity_Id := Empty;
722 if Is_Entry (Current_Scope)
723 and then Is_Task_Type (Etype (Scope (Current_Scope)))
725 Error_Msg_N ("task entries cannot have access parameters", N);
729 -- Ada 2005: for an object declaration the corresponding anonymous
730 -- type is declared in the current scope.
732 -- If the access definition is the return type of another access to
733 -- function, scope is the current one, because it is the one of the
734 -- current type declaration.
736 if Nkind_In (Related_Nod, N_Object_Declaration,
737 N_Access_Function_Definition)
739 Anon_Scope := Current_Scope;
741 -- For the anonymous function result case, retrieve the scope of the
742 -- function specification's associated entity rather than using the
743 -- current scope. The current scope will be the function itself if the
744 -- formal part is currently being analyzed, but will be the parent scope
745 -- in the case of a parameterless function, and we always want to use
746 -- the function's parent scope. Finally, if the function is a child
747 -- unit, we must traverse the tree to retrieve the proper entity.
749 elsif Nkind (Related_Nod) = N_Function_Specification
750 and then Nkind (Parent (N)) /= N_Parameter_Specification
752 -- If the current scope is a protected type, the anonymous access
753 -- is associated with one of the protected operations, and must
754 -- be available in the scope that encloses the protected declaration.
755 -- Otherwise the type is in the scope enclosing the subprogram.
757 -- If the function has formals, The return type of a subprogram
758 -- declaration is analyzed in the scope of the subprogram (see
759 -- Process_Formals) and thus the protected type, if present, is
760 -- the scope of the current function scope.
762 if Ekind (Current_Scope) = E_Protected_Type then
763 Enclosing_Prot_Type := Current_Scope;
765 elsif Ekind (Current_Scope) = E_Function
766 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
768 Enclosing_Prot_Type := Scope (Current_Scope);
771 if Present (Enclosing_Prot_Type) then
772 Anon_Scope := Scope (Enclosing_Prot_Type);
775 Anon_Scope := Scope (Defining_Entity (Related_Nod));
779 -- For access formals, access components, and access discriminants,
780 -- the scope is that of the enclosing declaration,
782 Anon_Scope := Scope (Current_Scope);
787 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
790 and then Ada_Version >= Ada_05
792 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
795 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
796 -- the corresponding semantic routine
798 if Present (Access_To_Subprogram_Definition (N)) then
799 Access_Subprogram_Declaration
800 (T_Name => Anon_Type,
801 T_Def => Access_To_Subprogram_Definition (N));
803 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
805 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
808 (Anon_Type, E_Anonymous_Access_Subprogram_Type);
811 Set_Can_Use_Internal_Rep
812 (Anon_Type, not Always_Compatible_Rep_On_Target);
814 -- If the anonymous access is associated with a protected operation
815 -- create a reference to it after the enclosing protected definition
816 -- because the itype will be used in the subsequent bodies.
818 if Ekind (Current_Scope) = E_Protected_Type then
819 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
825 Find_Type (Subtype_Mark (N));
826 Desig_Type := Entity (Subtype_Mark (N));
828 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
829 Set_Etype (Anon_Type, Anon_Type);
831 -- Make sure the anonymous access type has size and alignment fields
832 -- set, as required by gigi. This is necessary in the case of the
833 -- Task_Body_Procedure.
835 if not Has_Private_Component (Desig_Type) then
836 Layout_Type (Anon_Type);
839 -- ???The following makes no sense, because Anon_Type is an access type
840 -- and therefore cannot have components, private or otherwise. Hence
841 -- the assertion. Not sure what was meant, here.
842 Set_Depends_On_Private (Anon_Type, Has_Private_Component (Anon_Type));
843 pragma Assert (not Depends_On_Private (Anon_Type));
845 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
846 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
847 -- the null value is allowed. In Ada 95 the null value is never allowed.
849 if Ada_Version >= Ada_05 then
850 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
852 Set_Can_Never_Be_Null (Anon_Type, True);
855 -- The anonymous access type is as public as the discriminated type or
856 -- subprogram that defines it. It is imported (for back-end purposes)
857 -- if the designated type is.
859 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
861 -- Ada 2005 (AI-231): Propagate the access-constant attribute
863 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
865 -- The context is either a subprogram declaration, object declaration,
866 -- or an access discriminant, in a private or a full type declaration.
867 -- In the case of a subprogram, if the designated type is incomplete,
868 -- the operation will be a primitive operation of the full type, to be
869 -- updated subsequently. If the type is imported through a limited_with
870 -- clause, the subprogram is not a primitive operation of the type
871 -- (which is declared elsewhere in some other scope).
873 if Ekind (Desig_Type) = E_Incomplete_Type
874 and then not From_With_Type (Desig_Type)
875 and then Is_Overloadable (Current_Scope)
877 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
878 Set_Has_Delayed_Freeze (Current_Scope);
881 -- Ada 2005: if the designated type is an interface that may contain
882 -- tasks, create a Master entity for the declaration. This must be done
883 -- before expansion of the full declaration, because the declaration may
884 -- include an expression that is an allocator, whose expansion needs the
885 -- proper Master for the created tasks.
887 if Nkind (Related_Nod) = N_Object_Declaration
888 and then Expander_Active
890 if Is_Interface (Desig_Type)
891 and then Is_Limited_Record (Desig_Type)
893 Build_Class_Wide_Master (Anon_Type);
895 -- Similarly, if the type is an anonymous access that designates
896 -- tasks, create a master entity for it in the current context.
898 elsif Has_Task (Desig_Type)
899 and then Comes_From_Source (Related_Nod)
901 if not Has_Master_Entity (Current_Scope) then
903 Make_Object_Declaration (Loc,
904 Defining_Identifier =>
905 Make_Defining_Identifier (Loc, Name_uMaster),
906 Constant_Present => True,
908 New_Reference_To (RTE (RE_Master_Id), Loc),
910 Make_Explicit_Dereference (Loc,
911 New_Reference_To (RTE (RE_Current_Master), Loc)));
913 Insert_Before (Related_Nod, Decl);
916 Set_Master_Id (Anon_Type, Defining_Identifier (Decl));
917 Set_Has_Master_Entity (Current_Scope);
919 Build_Master_Renaming (Related_Nod, Anon_Type);
924 -- For a private component of a protected type, it is imperative that
925 -- the back-end elaborate the type immediately after the protected
926 -- declaration, because this type will be used in the declarations
927 -- created for the component within each protected body, so we must
928 -- create an itype reference for it now.
930 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
931 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
933 -- Similarly, if the access definition is the return result of a
934 -- function, create an itype reference for it because it will be used
935 -- within the function body. For a regular function that is not a
936 -- compilation unit, insert reference after the declaration. For a
937 -- protected operation, insert it after the enclosing protected type
938 -- declaration. In either case, do not create a reference for a type
939 -- obtained through a limited_with clause, because this would introduce
940 -- semantic dependencies.
942 -- Similarly, do not create a reference if the designated type is a
943 -- generic formal, because no use of it will reach the backend.
945 elsif Nkind (Related_Nod) = N_Function_Specification
946 and then not From_With_Type (Desig_Type)
947 and then not Is_Generic_Type (Desig_Type)
949 if Present (Enclosing_Prot_Type) then
950 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
952 elsif Is_List_Member (Parent (Related_Nod))
953 and then Nkind (Parent (N)) /= N_Parameter_Specification
955 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
958 -- Finally, create an itype reference for an object declaration of an
959 -- anonymous access type. This is strictly necessary only for deferred
960 -- constants, but in any case will avoid out-of-scope problems in the
963 elsif Nkind (Related_Nod) = N_Object_Declaration then
964 Build_Itype_Reference (Anon_Type, Related_Nod);
968 end Access_Definition;
970 -----------------------------------
971 -- Access_Subprogram_Declaration --
972 -----------------------------------
974 procedure Access_Subprogram_Declaration
979 procedure Check_For_Premature_Usage (Def : Node_Id);
980 -- Check that type T_Name is not used, directly or recursively, as a
981 -- parameter or a return type in Def. Def is either a subtype, an
982 -- access_definition, or an access_to_subprogram_definition.
984 -------------------------------
985 -- Check_For_Premature_Usage --
986 -------------------------------
988 procedure Check_For_Premature_Usage (Def : Node_Id) is
992 -- Check for a subtype mark
994 if Nkind (Def) in N_Has_Etype then
995 if Etype (Def) = T_Name then
997 ("type& cannot be used before end of its declaration", Def);
1000 -- If this is not a subtype, then this is an access_definition
1002 elsif Nkind (Def) = N_Access_Definition then
1003 if Present (Access_To_Subprogram_Definition (Def)) then
1004 Check_For_Premature_Usage
1005 (Access_To_Subprogram_Definition (Def));
1007 Check_For_Premature_Usage (Subtype_Mark (Def));
1010 -- The only cases left are N_Access_Function_Definition and
1011 -- N_Access_Procedure_Definition.
1014 if Present (Parameter_Specifications (Def)) then
1015 Param := First (Parameter_Specifications (Def));
1016 while Present (Param) loop
1017 Check_For_Premature_Usage (Parameter_Type (Param));
1018 Param := Next (Param);
1022 if Nkind (Def) = N_Access_Function_Definition then
1023 Check_For_Premature_Usage (Result_Definition (Def));
1026 end Check_For_Premature_Usage;
1030 Formals : constant List_Id := Parameter_Specifications (T_Def);
1033 Desig_Type : constant Entity_Id :=
1034 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1036 -- Start of processing for Access_Subprogram_Declaration
1039 -- Associate the Itype node with the inner full-type declaration or
1040 -- subprogram spec. This is required to handle nested anonymous
1041 -- declarations. For example:
1044 -- (X : access procedure
1045 -- (Y : access procedure
1048 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1049 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1050 N_Private_Type_Declaration,
1051 N_Private_Extension_Declaration,
1052 N_Procedure_Specification,
1053 N_Function_Specification)
1055 Nkind_In (D_Ityp, N_Object_Declaration,
1056 N_Object_Renaming_Declaration,
1057 N_Formal_Object_Declaration,
1058 N_Formal_Type_Declaration,
1059 N_Task_Type_Declaration,
1060 N_Protected_Type_Declaration))
1062 D_Ityp := Parent (D_Ityp);
1063 pragma Assert (D_Ityp /= Empty);
1066 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1068 if Nkind_In (D_Ityp, N_Procedure_Specification,
1069 N_Function_Specification)
1071 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1073 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1074 N_Object_Declaration,
1075 N_Object_Renaming_Declaration,
1076 N_Formal_Type_Declaration)
1078 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1081 if Nkind (T_Def) = N_Access_Function_Definition then
1082 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1084 Acc : constant Node_Id := Result_Definition (T_Def);
1087 if Present (Access_To_Subprogram_Definition (Acc))
1089 Protected_Present (Access_To_Subprogram_Definition (Acc))
1093 Replace_Anonymous_Access_To_Protected_Subprogram
1099 Access_Definition (T_Def, Result_Definition (T_Def)));
1104 Analyze (Result_Definition (T_Def));
1107 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1110 -- If a null exclusion is imposed on the result type, then
1111 -- create a null-excluding itype (an access subtype) and use
1112 -- it as the function's Etype.
1114 if Is_Access_Type (Typ)
1115 and then Null_Exclusion_In_Return_Present (T_Def)
1117 Set_Etype (Desig_Type,
1118 Create_Null_Excluding_Itype
1120 Related_Nod => T_Def,
1121 Scope_Id => Current_Scope));
1124 if From_With_Type (Typ) then
1126 ("illegal use of incomplete type&",
1127 Result_Definition (T_Def), Typ);
1129 elsif Ekind (Current_Scope) = E_Package
1130 and then In_Private_Part (Current_Scope)
1132 if Ekind (Typ) = E_Incomplete_Type then
1133 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1135 elsif Is_Class_Wide_Type (Typ)
1136 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1139 (Desig_Type, Private_Dependents (Etype (Typ)));
1143 Set_Etype (Desig_Type, Typ);
1148 if not (Is_Type (Etype (Desig_Type))) then
1150 ("expect type in function specification",
1151 Result_Definition (T_Def));
1155 Set_Etype (Desig_Type, Standard_Void_Type);
1158 if Present (Formals) then
1159 Push_Scope (Desig_Type);
1161 -- A bit of a kludge here. These kludges will be removed when Itypes
1162 -- have proper parent pointers to their declarations???
1164 -- Kludge 1) Link defining_identifier of formals. Required by
1165 -- First_Formal to provide its functionality.
1171 F := First (Formals);
1172 while Present (F) loop
1173 if No (Parent (Defining_Identifier (F))) then
1174 Set_Parent (Defining_Identifier (F), F);
1181 Process_Formals (Formals, Parent (T_Def));
1183 -- Kludge 2) End_Scope requires that the parent pointer be set to
1184 -- something reasonable, but Itypes don't have parent pointers. So
1185 -- we set it and then unset it ???
1187 Set_Parent (Desig_Type, T_Name);
1189 Set_Parent (Desig_Type, Empty);
1192 -- Check for premature usage of the type being defined
1194 Check_For_Premature_Usage (T_Def);
1196 -- The return type and/or any parameter type may be incomplete. Mark
1197 -- the subprogram_type as depending on the incomplete type, so that
1198 -- it can be updated when the full type declaration is seen. This
1199 -- only applies to incomplete types declared in some enclosing scope,
1200 -- not to limited views from other packages.
1202 if Present (Formals) then
1203 Formal := First_Formal (Desig_Type);
1204 while Present (Formal) loop
1205 if Ekind (Formal) /= E_In_Parameter
1206 and then Nkind (T_Def) = N_Access_Function_Definition
1208 Error_Msg_N ("functions can only have IN parameters", Formal);
1211 if Ekind (Etype (Formal)) = E_Incomplete_Type
1212 and then In_Open_Scopes (Scope (Etype (Formal)))
1214 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1215 Set_Has_Delayed_Freeze (Desig_Type);
1218 Next_Formal (Formal);
1222 -- If the return type is incomplete, this is legal as long as the
1223 -- type is declared in the current scope and will be completed in
1224 -- it (rather than being part of limited view).
1226 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1227 and then not Has_Delayed_Freeze (Desig_Type)
1228 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1230 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1231 Set_Has_Delayed_Freeze (Desig_Type);
1234 Check_Delayed_Subprogram (Desig_Type);
1236 if Protected_Present (T_Def) then
1237 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1238 Set_Convention (Desig_Type, Convention_Protected);
1240 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1243 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1245 Set_Etype (T_Name, T_Name);
1246 Init_Size_Align (T_Name);
1247 Set_Directly_Designated_Type (T_Name, Desig_Type);
1249 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1251 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1253 Check_Restriction (No_Access_Subprograms, T_Def);
1254 end Access_Subprogram_Declaration;
1256 ----------------------------
1257 -- Access_Type_Declaration --
1258 ----------------------------
1260 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1261 S : constant Node_Id := Subtype_Indication (Def);
1262 P : constant Node_Id := Parent (Def);
1264 -- Check for permissible use of incomplete type
1266 if Nkind (S) /= N_Subtype_Indication then
1269 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1270 Set_Directly_Designated_Type (T, Entity (S));
1272 Set_Directly_Designated_Type (T,
1273 Process_Subtype (S, P, T, 'P'));
1277 Set_Directly_Designated_Type (T,
1278 Process_Subtype (S, P, T, 'P'));
1281 if All_Present (Def) or Constant_Present (Def) then
1282 Set_Ekind (T, E_General_Access_Type);
1284 Set_Ekind (T, E_Access_Type);
1287 if Base_Type (Designated_Type (T)) = T then
1288 Error_Msg_N ("access type cannot designate itself", S);
1290 -- In Ada 2005, the type may have a limited view through some unit
1291 -- in its own context, allowing the following circularity that cannot
1292 -- be detected earlier
1294 elsif Is_Class_Wide_Type (Designated_Type (T))
1295 and then Etype (Designated_Type (T)) = T
1298 ("access type cannot designate its own classwide type", S);
1300 -- Clean up indication of tagged status to prevent cascaded errors
1302 Set_Is_Tagged_Type (T, False);
1307 -- If the type has appeared already in a with_type clause, it is
1308 -- frozen and the pointer size is already set. Else, initialize.
1310 if not From_With_Type (T) then
1311 Init_Size_Align (T);
1314 -- Note that Has_Task is always false, since the access type itself
1315 -- is not a task type. See Einfo for more description on this point.
1316 -- Exactly the same consideration applies to Has_Controlled_Component.
1318 Set_Has_Task (T, False);
1319 Set_Has_Controlled_Component (T, False);
1321 -- Initialize Associated_Final_Chain explicitly to Empty, to avoid
1322 -- problems where an incomplete view of this entity has been previously
1323 -- established by a limited with and an overlaid version of this field
1324 -- (Stored_Constraint) was initialized for the incomplete view.
1326 Set_Associated_Final_Chain (T, Empty);
1328 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1331 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1332 Set_Is_Access_Constant (T, Constant_Present (Def));
1333 end Access_Type_Declaration;
1335 ----------------------------------
1336 -- Add_Interface_Tag_Components --
1337 ----------------------------------
1339 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1340 Loc : constant Source_Ptr := Sloc (N);
1344 procedure Add_Tag (Iface : Entity_Id);
1345 -- Add tag for one of the progenitor interfaces
1351 procedure Add_Tag (Iface : Entity_Id) is
1358 pragma Assert (Is_Tagged_Type (Iface)
1359 and then Is_Interface (Iface));
1362 Make_Component_Definition (Loc,
1363 Aliased_Present => True,
1364 Subtype_Indication =>
1365 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1367 Tag := Make_Defining_Identifier (Loc, New_Internal_Name ('V'));
1370 Make_Component_Declaration (Loc,
1371 Defining_Identifier => Tag,
1372 Component_Definition => Def);
1374 Analyze_Component_Declaration (Decl);
1376 Set_Analyzed (Decl);
1377 Set_Ekind (Tag, E_Component);
1379 Set_Is_Aliased (Tag);
1380 Set_Related_Type (Tag, Iface);
1381 Init_Component_Location (Tag);
1383 pragma Assert (Is_Frozen (Iface));
1385 Set_DT_Entry_Count (Tag,
1386 DT_Entry_Count (First_Entity (Iface)));
1388 if No (Last_Tag) then
1391 Insert_After (Last_Tag, Decl);
1396 -- If the ancestor has discriminants we need to give special support
1397 -- to store the offset_to_top value of the secondary dispatch tables.
1398 -- For this purpose we add a supplementary component just after the
1399 -- field that contains the tag associated with each secondary DT.
1401 if Typ /= Etype (Typ)
1402 and then Has_Discriminants (Etype (Typ))
1405 Make_Component_Definition (Loc,
1406 Subtype_Indication =>
1407 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1410 Make_Defining_Identifier (Loc, New_Internal_Name ('V'));
1413 Make_Component_Declaration (Loc,
1414 Defining_Identifier => Offset,
1415 Component_Definition => Def);
1417 Analyze_Component_Declaration (Decl);
1419 Set_Analyzed (Decl);
1420 Set_Ekind (Offset, E_Component);
1421 Set_Is_Aliased (Offset);
1422 Set_Related_Type (Offset, Iface);
1423 Init_Component_Location (Offset);
1424 Insert_After (Last_Tag, Decl);
1435 -- Start of processing for Add_Interface_Tag_Components
1438 if not RTE_Available (RE_Interface_Tag) then
1440 ("(Ada 2005) interface types not supported by this run-time!",
1445 if Ekind (Typ) /= E_Record_Type
1446 or else (Is_Concurrent_Record_Type (Typ)
1447 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1448 or else (not Is_Concurrent_Record_Type (Typ)
1449 and then No (Interfaces (Typ))
1450 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1455 -- Find the current last tag
1457 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1458 Ext := Record_Extension_Part (Type_Definition (N));
1460 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1461 Ext := Type_Definition (N);
1466 if not (Present (Component_List (Ext))) then
1467 Set_Null_Present (Ext, False);
1469 Set_Component_List (Ext,
1470 Make_Component_List (Loc,
1471 Component_Items => L,
1472 Null_Present => False));
1474 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1475 L := Component_Items
1477 (Record_Extension_Part
1478 (Type_Definition (N))));
1480 L := Component_Items
1482 (Type_Definition (N)));
1485 -- Find the last tag component
1488 while Present (Comp) loop
1489 if Nkind (Comp) = N_Component_Declaration
1490 and then Is_Tag (Defining_Identifier (Comp))
1499 -- At this point L references the list of components and Last_Tag
1500 -- references the current last tag (if any). Now we add the tag
1501 -- corresponding with all the interfaces that are not implemented
1504 if Present (Interfaces (Typ)) then
1505 Elmt := First_Elmt (Interfaces (Typ));
1506 while Present (Elmt) loop
1507 Add_Tag (Node (Elmt));
1511 end Add_Interface_Tag_Components;
1513 -------------------------------------
1514 -- Add_Internal_Interface_Entities --
1515 -------------------------------------
1517 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1520 Iface_Elmt : Elmt_Id;
1521 Iface_Prim : Entity_Id;
1522 Ifaces_List : Elist_Id;
1523 New_Subp : Entity_Id := Empty;
1527 pragma Assert (Ada_Version >= Ada_05
1528 and then Is_Record_Type (Tagged_Type)
1529 and then Is_Tagged_Type (Tagged_Type)
1530 and then Has_Interfaces (Tagged_Type)
1531 and then not Is_Interface (Tagged_Type));
1533 Collect_Interfaces (Tagged_Type, Ifaces_List);
1535 Iface_Elmt := First_Elmt (Ifaces_List);
1536 while Present (Iface_Elmt) loop
1537 Iface := Node (Iface_Elmt);
1539 -- Exclude from this processing interfaces that are parents of
1540 -- Tagged_Type because their primitives are located in the primary
1541 -- dispatch table (and hence no auxiliary internal entities are
1542 -- required to handle secondary dispatch tables in such case).
1544 if not Is_Ancestor (Iface, Tagged_Type) then
1545 Elmt := First_Elmt (Primitive_Operations (Iface));
1546 while Present (Elmt) loop
1547 Iface_Prim := Node (Elmt);
1549 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1551 Find_Primitive_Covering_Interface
1552 (Tagged_Type => Tagged_Type,
1553 Iface_Prim => Iface_Prim);
1555 pragma Assert (Present (Prim));
1558 (New_Subp => New_Subp,
1559 Parent_Subp => Iface_Prim,
1560 Derived_Type => Tagged_Type,
1561 Parent_Type => Iface);
1563 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1564 -- associated with interface types. These entities are
1565 -- only registered in the list of primitives of its
1566 -- corresponding tagged type because they are only used
1567 -- to fill the contents of the secondary dispatch tables.
1568 -- Therefore they are removed from the homonym chains.
1570 Set_Is_Hidden (New_Subp);
1571 Set_Is_Internal (New_Subp);
1572 Set_Alias (New_Subp, Prim);
1573 Set_Is_Abstract_Subprogram (New_Subp,
1574 Is_Abstract_Subprogram (Prim));
1575 Set_Interface_Alias (New_Subp, Iface_Prim);
1577 -- Internal entities associated with interface types are
1578 -- only registered in the list of primitives of the tagged
1579 -- type. They are only used to fill the contents of the
1580 -- secondary dispatch tables. Therefore they are not needed
1581 -- in the homonym chains.
1583 Remove_Homonym (New_Subp);
1585 -- Hidden entities associated with interfaces must have set
1586 -- the Has_Delay_Freeze attribute to ensure that, in case of
1587 -- locally defined tagged types (or compiling with static
1588 -- dispatch tables generation disabled) the corresponding
1589 -- entry of the secondary dispatch table is filled when
1590 -- such an entity is frozen.
1592 Set_Has_Delayed_Freeze (New_Subp);
1599 Next_Elmt (Iface_Elmt);
1601 end Add_Internal_Interface_Entities;
1603 -----------------------------------
1604 -- Analyze_Component_Declaration --
1605 -----------------------------------
1607 procedure Analyze_Component_Declaration (N : Node_Id) is
1608 Id : constant Entity_Id := Defining_Identifier (N);
1609 E : constant Node_Id := Expression (N);
1613 function Contains_POC (Constr : Node_Id) return Boolean;
1614 -- Determines whether a constraint uses the discriminant of a record
1615 -- type thus becoming a per-object constraint (POC).
1617 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1618 -- Typ is the type of the current component, check whether this type is
1619 -- a limited type. Used to validate declaration against that of
1620 -- enclosing record.
1626 function Contains_POC (Constr : Node_Id) return Boolean is
1628 -- Prevent cascaded errors
1630 if Error_Posted (Constr) then
1634 case Nkind (Constr) is
1635 when N_Attribute_Reference =>
1637 Attribute_Name (Constr) = Name_Access
1638 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1640 when N_Discriminant_Association =>
1641 return Denotes_Discriminant (Expression (Constr));
1643 when N_Identifier =>
1644 return Denotes_Discriminant (Constr);
1646 when N_Index_Or_Discriminant_Constraint =>
1651 IDC := First (Constraints (Constr));
1652 while Present (IDC) loop
1654 -- One per-object constraint is sufficient
1656 if Contains_POC (IDC) then
1667 return Denotes_Discriminant (Low_Bound (Constr))
1669 Denotes_Discriminant (High_Bound (Constr));
1671 when N_Range_Constraint =>
1672 return Denotes_Discriminant (Range_Expression (Constr));
1680 ----------------------
1681 -- Is_Known_Limited --
1682 ----------------------
1684 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1685 P : constant Entity_Id := Etype (Typ);
1686 R : constant Entity_Id := Root_Type (Typ);
1689 if Is_Limited_Record (Typ) then
1692 -- If the root type is limited (and not a limited interface)
1693 -- so is the current type
1695 elsif Is_Limited_Record (R)
1697 (not Is_Interface (R)
1698 or else not Is_Limited_Interface (R))
1702 -- Else the type may have a limited interface progenitor, but a
1703 -- limited record parent.
1706 and then Is_Limited_Record (P)
1713 end Is_Known_Limited;
1715 -- Start of processing for Analyze_Component_Declaration
1718 Generate_Definition (Id);
1721 if Present (Subtype_Indication (Component_Definition (N))) then
1722 T := Find_Type_Of_Object
1723 (Subtype_Indication (Component_Definition (N)), N);
1725 -- Ada 2005 (AI-230): Access Definition case
1728 pragma Assert (Present
1729 (Access_Definition (Component_Definition (N))));
1731 T := Access_Definition
1733 N => Access_Definition (Component_Definition (N)));
1734 Set_Is_Local_Anonymous_Access (T);
1736 -- Ada 2005 (AI-254)
1738 if Present (Access_To_Subprogram_Definition
1739 (Access_Definition (Component_Definition (N))))
1740 and then Protected_Present (Access_To_Subprogram_Definition
1742 (Component_Definition (N))))
1744 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1748 -- If the subtype is a constrained subtype of the enclosing record,
1749 -- (which must have a partial view) the back-end does not properly
1750 -- handle the recursion. Rewrite the component declaration with an
1751 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1752 -- the tree directly because side effects have already been removed from
1753 -- discriminant constraints.
1755 if Ekind (T) = E_Access_Subtype
1756 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1757 and then Comes_From_Source (T)
1758 and then Nkind (Parent (T)) = N_Subtype_Declaration
1759 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1762 (Subtype_Indication (Component_Definition (N)),
1763 New_Copy_Tree (Subtype_Indication (Parent (T))));
1764 T := Find_Type_Of_Object
1765 (Subtype_Indication (Component_Definition (N)), N);
1768 -- If the component declaration includes a default expression, then we
1769 -- check that the component is not of a limited type (RM 3.7(5)),
1770 -- and do the special preanalysis of the expression (see section on
1771 -- "Handling of Default and Per-Object Expressions" in the spec of
1775 Preanalyze_Spec_Expression (E, T);
1776 Check_Initialization (T, E);
1778 if Ada_Version >= Ada_05
1779 and then Ekind (T) = E_Anonymous_Access_Type
1780 and then Etype (E) /= Any_Type
1782 -- Check RM 3.9.2(9): "if the expected type for an expression is
1783 -- an anonymous access-to-specific tagged type, then the object
1784 -- designated by the expression shall not be dynamically tagged
1785 -- unless it is a controlling operand in a call on a dispatching
1788 if Is_Tagged_Type (Directly_Designated_Type (T))
1790 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1792 Ekind (Directly_Designated_Type (Etype (E))) =
1796 ("access to specific tagged type required (RM 3.9.2(9))", E);
1799 -- (Ada 2005: AI-230): Accessibility check for anonymous
1802 if Type_Access_Level (Etype (E)) > Type_Access_Level (T) then
1804 ("expression has deeper access level than component " &
1805 "(RM 3.10.2 (12.2))", E);
1808 -- The initialization expression is a reference to an access
1809 -- discriminant. The type of the discriminant is always deeper
1810 -- than any access type.
1812 if Ekind (Etype (E)) = E_Anonymous_Access_Type
1813 and then Is_Entity_Name (E)
1814 and then Ekind (Entity (E)) = E_In_Parameter
1815 and then Present (Discriminal_Link (Entity (E)))
1818 ("discriminant has deeper accessibility level than target",
1824 -- The parent type may be a private view with unknown discriminants,
1825 -- and thus unconstrained. Regular components must be constrained.
1827 if Is_Indefinite_Subtype (T) and then Chars (Id) /= Name_uParent then
1828 if Is_Class_Wide_Type (T) then
1830 ("class-wide subtype with unknown discriminants" &
1831 " in component declaration",
1832 Subtype_Indication (Component_Definition (N)));
1835 ("unconstrained subtype in component declaration",
1836 Subtype_Indication (Component_Definition (N)));
1839 -- Components cannot be abstract, except for the special case of
1840 -- the _Parent field (case of extending an abstract tagged type)
1842 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
1843 Error_Msg_N ("type of a component cannot be abstract", N);
1847 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
1849 -- The component declaration may have a per-object constraint, set
1850 -- the appropriate flag in the defining identifier of the subtype.
1852 if Present (Subtype_Indication (Component_Definition (N))) then
1854 Sindic : constant Node_Id :=
1855 Subtype_Indication (Component_Definition (N));
1857 if Nkind (Sindic) = N_Subtype_Indication
1858 and then Present (Constraint (Sindic))
1859 and then Contains_POC (Constraint (Sindic))
1861 Set_Has_Per_Object_Constraint (Id);
1866 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
1867 -- out some static checks.
1869 if Ada_Version >= Ada_05
1870 and then Can_Never_Be_Null (T)
1872 Null_Exclusion_Static_Checks (N);
1875 -- If this component is private (or depends on a private type), flag the
1876 -- record type to indicate that some operations are not available.
1878 P := Private_Component (T);
1882 -- Check for circular definitions
1884 if P = Any_Type then
1885 Set_Etype (Id, Any_Type);
1887 -- There is a gap in the visibility of operations only if the
1888 -- component type is not defined in the scope of the record type.
1890 elsif Scope (P) = Scope (Current_Scope) then
1893 elsif Is_Limited_Type (P) then
1894 Set_Is_Limited_Composite (Current_Scope);
1897 Set_Is_Private_Composite (Current_Scope);
1902 and then Is_Limited_Type (T)
1903 and then Chars (Id) /= Name_uParent
1904 and then Is_Tagged_Type (Current_Scope)
1906 if Is_Derived_Type (Current_Scope)
1907 and then not Is_Known_Limited (Current_Scope)
1910 ("extension of nonlimited type cannot have limited components",
1913 if Is_Interface (Root_Type (Current_Scope)) then
1915 ("\limitedness is not inherited from limited interface", N);
1917 ("\add LIMITED to type indication", N);
1920 Explain_Limited_Type (T, N);
1921 Set_Etype (Id, Any_Type);
1922 Set_Is_Limited_Composite (Current_Scope, False);
1924 elsif not Is_Derived_Type (Current_Scope)
1925 and then not Is_Limited_Record (Current_Scope)
1926 and then not Is_Concurrent_Type (Current_Scope)
1929 ("nonlimited tagged type cannot have limited components", N);
1930 Explain_Limited_Type (T, N);
1931 Set_Etype (Id, Any_Type);
1932 Set_Is_Limited_Composite (Current_Scope, False);
1936 Set_Original_Record_Component (Id, Id);
1937 end Analyze_Component_Declaration;
1939 --------------------------
1940 -- Analyze_Declarations --
1941 --------------------------
1943 procedure Analyze_Declarations (L : List_Id) is
1945 Freeze_From : Entity_Id := Empty;
1946 Next_Node : Node_Id;
1949 -- Adjust D not to include implicit label declarations, since these
1950 -- have strange Sloc values that result in elaboration check problems.
1951 -- (They have the sloc of the label as found in the source, and that
1952 -- is ahead of the current declarative part).
1958 procedure Adjust_D is
1960 while Present (Prev (D))
1961 and then Nkind (D) = N_Implicit_Label_Declaration
1967 -- Start of processing for Analyze_Declarations
1971 while Present (D) loop
1973 -- Complete analysis of declaration
1976 Next_Node := Next (D);
1978 if No (Freeze_From) then
1979 Freeze_From := First_Entity (Current_Scope);
1982 -- At the end of a declarative part, freeze remaining entities
1983 -- declared in it. The end of the visible declarations of package
1984 -- specification is not the end of a declarative part if private
1985 -- declarations are present. The end of a package declaration is a
1986 -- freezing point only if it a library package. A task definition or
1987 -- protected type definition is not a freeze point either. Finally,
1988 -- we do not freeze entities in generic scopes, because there is no
1989 -- code generated for them and freeze nodes will be generated for
1992 -- The end of a package instantiation is not a freeze point, but
1993 -- for now we make it one, because the generic body is inserted
1994 -- (currently) immediately after. Generic instantiations will not
1995 -- be a freeze point once delayed freezing of bodies is implemented.
1996 -- (This is needed in any case for early instantiations ???).
1998 if No (Next_Node) then
1999 if Nkind_In (Parent (L), N_Component_List,
2001 N_Protected_Definition)
2005 elsif Nkind (Parent (L)) /= N_Package_Specification then
2006 if Nkind (Parent (L)) = N_Package_Body then
2007 Freeze_From := First_Entity (Current_Scope);
2011 Freeze_All (Freeze_From, D);
2012 Freeze_From := Last_Entity (Current_Scope);
2014 elsif Scope (Current_Scope) /= Standard_Standard
2015 and then not Is_Child_Unit (Current_Scope)
2016 and then No (Generic_Parent (Parent (L)))
2020 elsif L /= Visible_Declarations (Parent (L))
2021 or else No (Private_Declarations (Parent (L)))
2022 or else Is_Empty_List (Private_Declarations (Parent (L)))
2025 Freeze_All (Freeze_From, D);
2026 Freeze_From := Last_Entity (Current_Scope);
2029 -- If next node is a body then freeze all types before the body.
2030 -- An exception occurs for some expander-generated bodies. If these
2031 -- are generated at places where in general language rules would not
2032 -- allow a freeze point, then we assume that the expander has
2033 -- explicitly checked that all required types are properly frozen,
2034 -- and we do not cause general freezing here. This special circuit
2035 -- is used when the encountered body is marked as having already
2038 -- In all other cases (bodies that come from source, and expander
2039 -- generated bodies that have not been analyzed yet), freeze all
2040 -- types now. Note that in the latter case, the expander must take
2041 -- care to attach the bodies at a proper place in the tree so as to
2042 -- not cause unwanted freezing at that point.
2044 elsif not Analyzed (Next_Node)
2045 and then (Nkind_In (Next_Node, N_Subprogram_Body,
2051 Nkind (Next_Node) in N_Body_Stub)
2054 Freeze_All (Freeze_From, D);
2055 Freeze_From := Last_Entity (Current_Scope);
2060 end Analyze_Declarations;
2062 ----------------------------------
2063 -- Analyze_Incomplete_Type_Decl --
2064 ----------------------------------
2066 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
2067 F : constant Boolean := Is_Pure (Current_Scope);
2071 Generate_Definition (Defining_Identifier (N));
2073 -- Process an incomplete declaration. The identifier must not have been
2074 -- declared already in the scope. However, an incomplete declaration may
2075 -- appear in the private part of a package, for a private type that has
2076 -- already been declared.
2078 -- In this case, the discriminants (if any) must match
2080 T := Find_Type_Name (N);
2082 Set_Ekind (T, E_Incomplete_Type);
2083 Init_Size_Align (T);
2084 Set_Is_First_Subtype (T, True);
2087 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
2088 -- incomplete types.
2090 if Tagged_Present (N) then
2091 Set_Is_Tagged_Type (T);
2092 Make_Class_Wide_Type (T);
2093 Set_Primitive_Operations (T, New_Elmt_List);
2098 Set_Stored_Constraint (T, No_Elist);
2100 if Present (Discriminant_Specifications (N)) then
2101 Process_Discriminants (N);
2106 -- If the type has discriminants, non-trivial subtypes may be
2107 -- declared before the full view of the type. The full views of those
2108 -- subtypes will be built after the full view of the type.
2110 Set_Private_Dependents (T, New_Elmt_List);
2112 end Analyze_Incomplete_Type_Decl;
2114 -----------------------------------
2115 -- Analyze_Interface_Declaration --
2116 -----------------------------------
2118 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
2119 CW : constant Entity_Id := Class_Wide_Type (T);
2122 Set_Is_Tagged_Type (T);
2124 Set_Is_Limited_Record (T, Limited_Present (Def)
2125 or else Task_Present (Def)
2126 or else Protected_Present (Def)
2127 or else Synchronized_Present (Def));
2129 -- Type is abstract if full declaration carries keyword, or if previous
2130 -- partial view did.
2132 Set_Is_Abstract_Type (T);
2133 Set_Is_Interface (T);
2135 -- Type is a limited interface if it includes the keyword limited, task,
2136 -- protected, or synchronized.
2138 Set_Is_Limited_Interface
2139 (T, Limited_Present (Def)
2140 or else Protected_Present (Def)
2141 or else Synchronized_Present (Def)
2142 or else Task_Present (Def));
2144 Set_Is_Protected_Interface (T, Protected_Present (Def));
2145 Set_Is_Task_Interface (T, Task_Present (Def));
2147 -- Type is a synchronized interface if it includes the keyword task,
2148 -- protected, or synchronized.
2150 Set_Is_Synchronized_Interface
2151 (T, Synchronized_Present (Def)
2152 or else Protected_Present (Def)
2153 or else Task_Present (Def));
2155 Set_Interfaces (T, New_Elmt_List);
2156 Set_Primitive_Operations (T, New_Elmt_List);
2158 -- Complete the decoration of the class-wide entity if it was already
2159 -- built (i.e. during the creation of the limited view)
2161 if Present (CW) then
2162 Set_Is_Interface (CW);
2163 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
2164 Set_Is_Protected_Interface (CW, Is_Protected_Interface (T));
2165 Set_Is_Synchronized_Interface (CW, Is_Synchronized_Interface (T));
2166 Set_Is_Task_Interface (CW, Is_Task_Interface (T));
2169 -- Check runtime support for synchronized interfaces
2171 if VM_Target = No_VM
2172 and then (Is_Task_Interface (T)
2173 or else Is_Protected_Interface (T)
2174 or else Is_Synchronized_Interface (T))
2175 and then not RTE_Available (RE_Select_Specific_Data)
2177 Error_Msg_CRT ("synchronized interfaces", T);
2179 end Analyze_Interface_Declaration;
2181 -----------------------------
2182 -- Analyze_Itype_Reference --
2183 -----------------------------
2185 -- Nothing to do. This node is placed in the tree only for the benefit of
2186 -- back end processing, and has no effect on the semantic processing.
2188 procedure Analyze_Itype_Reference (N : Node_Id) is
2190 pragma Assert (Is_Itype (Itype (N)));
2192 end Analyze_Itype_Reference;
2194 --------------------------------
2195 -- Analyze_Number_Declaration --
2196 --------------------------------
2198 procedure Analyze_Number_Declaration (N : Node_Id) is
2199 Id : constant Entity_Id := Defining_Identifier (N);
2200 E : constant Node_Id := Expression (N);
2202 Index : Interp_Index;
2206 Generate_Definition (Id);
2209 -- This is an optimization of a common case of an integer literal
2211 if Nkind (E) = N_Integer_Literal then
2212 Set_Is_Static_Expression (E, True);
2213 Set_Etype (E, Universal_Integer);
2215 Set_Etype (Id, Universal_Integer);
2216 Set_Ekind (Id, E_Named_Integer);
2217 Set_Is_Frozen (Id, True);
2221 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2223 -- Process expression, replacing error by integer zero, to avoid
2224 -- cascaded errors or aborts further along in the processing
2226 -- Replace Error by integer zero, which seems least likely to
2227 -- cause cascaded errors.
2230 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
2231 Set_Error_Posted (E);
2236 -- Verify that the expression is static and numeric. If
2237 -- the expression is overloaded, we apply the preference
2238 -- rule that favors root numeric types.
2240 if not Is_Overloaded (E) then
2246 Get_First_Interp (E, Index, It);
2247 while Present (It.Typ) loop
2248 if (Is_Integer_Type (It.Typ)
2249 or else Is_Real_Type (It.Typ))
2250 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
2252 if T = Any_Type then
2255 elsif It.Typ = Universal_Real
2256 or else It.Typ = Universal_Integer
2258 -- Choose universal interpretation over any other
2265 Get_Next_Interp (Index, It);
2269 if Is_Integer_Type (T) then
2271 Set_Etype (Id, Universal_Integer);
2272 Set_Ekind (Id, E_Named_Integer);
2274 elsif Is_Real_Type (T) then
2276 -- Because the real value is converted to universal_real, this is a
2277 -- legal context for a universal fixed expression.
2279 if T = Universal_Fixed then
2281 Loc : constant Source_Ptr := Sloc (N);
2282 Conv : constant Node_Id := Make_Type_Conversion (Loc,
2284 New_Occurrence_Of (Universal_Real, Loc),
2285 Expression => Relocate_Node (E));
2292 elsif T = Any_Fixed then
2293 Error_Msg_N ("illegal context for mixed mode operation", E);
2295 -- Expression is of the form : universal_fixed * integer. Try to
2296 -- resolve as universal_real.
2298 T := Universal_Real;
2303 Set_Etype (Id, Universal_Real);
2304 Set_Ekind (Id, E_Named_Real);
2307 Wrong_Type (E, Any_Numeric);
2311 Set_Ekind (Id, E_Constant);
2312 Set_Never_Set_In_Source (Id, True);
2313 Set_Is_True_Constant (Id, True);
2317 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
2318 Set_Etype (E, Etype (Id));
2321 if not Is_OK_Static_Expression (E) then
2322 Flag_Non_Static_Expr
2323 ("non-static expression used in number declaration!", E);
2324 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
2325 Set_Etype (E, Any_Type);
2327 end Analyze_Number_Declaration;
2329 --------------------------------
2330 -- Analyze_Object_Declaration --
2331 --------------------------------
2333 procedure Analyze_Object_Declaration (N : Node_Id) is
2334 Loc : constant Source_Ptr := Sloc (N);
2335 Id : constant Entity_Id := Defining_Identifier (N);
2339 E : Node_Id := Expression (N);
2340 -- E is set to Expression (N) throughout this routine. When
2341 -- Expression (N) is modified, E is changed accordingly.
2343 Prev_Entity : Entity_Id := Empty;
2345 function Count_Tasks (T : Entity_Id) return Uint;
2346 -- This function is called when a non-generic library level object of a
2347 -- task type is declared. Its function is to count the static number of
2348 -- tasks declared within the type (it is only called if Has_Tasks is set
2349 -- for T). As a side effect, if an array of tasks with non-static bounds
2350 -- or a variant record type is encountered, Check_Restrictions is called
2351 -- indicating the count is unknown.
2357 function Count_Tasks (T : Entity_Id) return Uint is
2363 if Is_Task_Type (T) then
2366 elsif Is_Record_Type (T) then
2367 if Has_Discriminants (T) then
2368 Check_Restriction (Max_Tasks, N);
2373 C := First_Component (T);
2374 while Present (C) loop
2375 V := V + Count_Tasks (Etype (C));
2382 elsif Is_Array_Type (T) then
2383 X := First_Index (T);
2384 V := Count_Tasks (Component_Type (T));
2385 while Present (X) loop
2388 if not Is_Static_Subtype (C) then
2389 Check_Restriction (Max_Tasks, N);
2392 V := V * (UI_Max (Uint_0,
2393 Expr_Value (Type_High_Bound (C)) -
2394 Expr_Value (Type_Low_Bound (C)) + Uint_1));
2407 -- Start of processing for Analyze_Object_Declaration
2410 -- There are three kinds of implicit types generated by an
2411 -- object declaration:
2413 -- 1. Those for generated by the original Object Definition
2415 -- 2. Those generated by the Expression
2417 -- 3. Those used to constrained the Object Definition with the
2418 -- expression constraints when it is unconstrained
2420 -- They must be generated in this order to avoid order of elaboration
2421 -- issues. Thus the first step (after entering the name) is to analyze
2422 -- the object definition.
2424 if Constant_Present (N) then
2425 Prev_Entity := Current_Entity_In_Scope (Id);
2427 if Present (Prev_Entity)
2429 -- If the homograph is an implicit subprogram, it is overridden
2430 -- by the current declaration.
2432 ((Is_Overloadable (Prev_Entity)
2433 and then Is_Inherited_Operation (Prev_Entity))
2435 -- The current object is a discriminal generated for an entry
2436 -- family index. Even though the index is a constant, in this
2437 -- particular context there is no true constant redeclaration.
2438 -- Enter_Name will handle the visibility.
2441 (Is_Discriminal (Id)
2442 and then Ekind (Discriminal_Link (Id)) =
2443 E_Entry_Index_Parameter)
2445 -- The current object is the renaming for a generic declared
2446 -- within the instance.
2449 (Ekind (Prev_Entity) = E_Package
2450 and then Nkind (Parent (Prev_Entity)) =
2451 N_Package_Renaming_Declaration
2452 and then not Comes_From_Source (Prev_Entity)
2453 and then Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
2455 Prev_Entity := Empty;
2459 if Present (Prev_Entity) then
2460 Constant_Redeclaration (Id, N, T);
2462 Generate_Reference (Prev_Entity, Id, 'c');
2463 Set_Completion_Referenced (Id);
2465 if Error_Posted (N) then
2467 -- Type mismatch or illegal redeclaration, Do not analyze
2468 -- expression to avoid cascaded errors.
2470 T := Find_Type_Of_Object (Object_Definition (N), N);
2472 Set_Ekind (Id, E_Variable);
2476 -- In the normal case, enter identifier at the start to catch premature
2477 -- usage in the initialization expression.
2480 Generate_Definition (Id);
2483 Mark_Coextensions (N, Object_Definition (N));
2485 T := Find_Type_Of_Object (Object_Definition (N), N);
2487 if Nkind (Object_Definition (N)) = N_Access_Definition
2489 (Access_To_Subprogram_Definition (Object_Definition (N)))
2490 and then Protected_Present
2491 (Access_To_Subprogram_Definition (Object_Definition (N)))
2493 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2496 if Error_Posted (Id) then
2498 Set_Ekind (Id, E_Variable);
2503 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2504 -- out some static checks
2506 if Ada_Version >= Ada_05
2507 and then Can_Never_Be_Null (T)
2509 -- In case of aggregates we must also take care of the correct
2510 -- initialization of nested aggregates bug this is done at the
2511 -- point of the analysis of the aggregate (see sem_aggr.adb)
2513 if Present (Expression (N))
2514 and then Nkind (Expression (N)) = N_Aggregate
2520 Save_Typ : constant Entity_Id := Etype (Id);
2522 Set_Etype (Id, T); -- Temp. decoration for static checks
2523 Null_Exclusion_Static_Checks (N);
2524 Set_Etype (Id, Save_Typ);
2529 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2531 -- If deferred constant, make sure context is appropriate. We detect
2532 -- a deferred constant as a constant declaration with no expression.
2533 -- A deferred constant can appear in a package body if its completion
2534 -- is by means of an interface pragma.
2536 if Constant_Present (N)
2539 -- A deferred constant may appear in the declarative part of the
2540 -- following constructs:
2544 -- extended return statements
2547 -- subprogram bodies
2550 -- When declared inside a package spec, a deferred constant must be
2551 -- completed by a full constant declaration or pragma Import. In all
2552 -- other cases, the only proper completion is pragma Import. Extended
2553 -- return statements are flagged as invalid contexts because they do
2554 -- not have a declarative part and so cannot accommodate the pragma.
2556 if Ekind (Current_Scope) = E_Return_Statement then
2558 ("invalid context for deferred constant declaration (RM 7.4)",
2561 ("\declaration requires an initialization expression",
2563 Set_Constant_Present (N, False);
2565 -- In Ada 83, deferred constant must be of private type
2567 elsif not Is_Private_Type (T) then
2568 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
2570 ("(Ada 83) deferred constant must be private type", N);
2574 -- If not a deferred constant, then object declaration freezes its type
2577 Check_Fully_Declared (T, N);
2578 Freeze_Before (N, T);
2581 -- If the object was created by a constrained array definition, then
2582 -- set the link in both the anonymous base type and anonymous subtype
2583 -- that are built to represent the array type to point to the object.
2585 if Nkind (Object_Definition (Declaration_Node (Id))) =
2586 N_Constrained_Array_Definition
2588 Set_Related_Array_Object (T, Id);
2589 Set_Related_Array_Object (Base_Type (T), Id);
2592 -- Special checks for protected objects not at library level
2594 if Is_Protected_Type (T)
2595 and then not Is_Library_Level_Entity (Id)
2597 Check_Restriction (No_Local_Protected_Objects, Id);
2599 -- Protected objects with interrupt handlers must be at library level
2601 -- Ada 2005: this test is not needed (and the corresponding clause
2602 -- in the RM is removed) because accessibility checks are sufficient
2603 -- to make handlers not at the library level illegal.
2605 if Has_Interrupt_Handler (T)
2606 and then Ada_Version < Ada_05
2609 ("interrupt object can only be declared at library level", Id);
2613 -- The actual subtype of the object is the nominal subtype, unless
2614 -- the nominal one is unconstrained and obtained from the expression.
2618 -- Process initialization expression if present and not in error
2620 if Present (E) and then E /= Error then
2622 -- Generate an error in case of CPP class-wide object initialization.
2623 -- Required because otherwise the expansion of the class-wide
2624 -- assignment would try to use 'size to initialize the object
2625 -- (primitive that is not available in CPP tagged types).
2627 if Is_Class_Wide_Type (Act_T)
2629 (Is_CPP_Class (Root_Type (Etype (Act_T)))
2631 (Present (Full_View (Root_Type (Etype (Act_T))))
2633 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
2636 ("predefined assignment not available for 'C'P'P tagged types",
2640 Mark_Coextensions (N, E);
2643 -- In case of errors detected in the analysis of the expression,
2644 -- decorate it with the expected type to avoid cascaded errors
2646 if No (Etype (E)) then
2650 -- If an initialization expression is present, then we set the
2651 -- Is_True_Constant flag. It will be reset if this is a variable
2652 -- and it is indeed modified.
2654 Set_Is_True_Constant (Id, True);
2656 -- If we are analyzing a constant declaration, set its completion
2657 -- flag after analyzing and resolving the expression.
2659 if Constant_Present (N) then
2660 Set_Has_Completion (Id);
2663 -- Set type and resolve (type may be overridden later on)
2668 -- If E is null and has been replaced by an N_Raise_Constraint_Error
2669 -- node (which was marked already-analyzed), we need to set the type
2670 -- to something other than Any_Access in order to keep gigi happy.
2672 if Etype (E) = Any_Access then
2676 -- If the object is an access to variable, the initialization
2677 -- expression cannot be an access to constant.
2679 if Is_Access_Type (T)
2680 and then not Is_Access_Constant (T)
2681 and then Is_Access_Type (Etype (E))
2682 and then Is_Access_Constant (Etype (E))
2685 ("access to variable cannot be initialized "
2686 & "with an access-to-constant expression", E);
2689 if not Assignment_OK (N) then
2690 Check_Initialization (T, E);
2693 Check_Unset_Reference (E);
2695 -- If this is a variable, then set current value. If this is a
2696 -- declared constant of a scalar type with a static expression,
2697 -- indicate that it is always valid.
2699 if not Constant_Present (N) then
2700 if Compile_Time_Known_Value (E) then
2701 Set_Current_Value (Id, E);
2704 elsif Is_Scalar_Type (T)
2705 and then Is_OK_Static_Expression (E)
2707 Set_Is_Known_Valid (Id);
2710 -- Deal with setting of null flags
2712 if Is_Access_Type (T) then
2713 if Known_Non_Null (E) then
2714 Set_Is_Known_Non_Null (Id, True);
2715 elsif Known_Null (E)
2716 and then not Can_Never_Be_Null (Id)
2718 Set_Is_Known_Null (Id, True);
2722 -- Check incorrect use of dynamically tagged expressions.
2724 if Is_Tagged_Type (T) then
2725 Check_Dynamically_Tagged_Expression
2731 Apply_Scalar_Range_Check (E, T);
2732 Apply_Static_Length_Check (E, T);
2735 -- If the No_Streams restriction is set, check that the type of the
2736 -- object is not, and does not contain, any subtype derived from
2737 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
2738 -- Has_Stream just for efficiency reasons. There is no point in
2739 -- spending time on a Has_Stream check if the restriction is not set.
2741 if Restrictions.Set (No_Streams) then
2742 if Has_Stream (T) then
2743 Check_Restriction (No_Streams, N);
2747 -- Case of unconstrained type
2749 if Is_Indefinite_Subtype (T) then
2751 -- Nothing to do in deferred constant case
2753 if Constant_Present (N) and then No (E) then
2756 -- Case of no initialization present
2759 if No_Initialization (N) then
2762 elsif Is_Class_Wide_Type (T) then
2764 ("initialization required in class-wide declaration ", N);
2768 ("unconstrained subtype not allowed (need initialization)",
2769 Object_Definition (N));
2771 if Is_Record_Type (T) and then Has_Discriminants (T) then
2773 ("\provide initial value or explicit discriminant values",
2774 Object_Definition (N));
2777 ("\or give default discriminant values for type&",
2778 Object_Definition (N), T);
2780 elsif Is_Array_Type (T) then
2782 ("\provide initial value or explicit array bounds",
2783 Object_Definition (N));
2787 -- Case of initialization present but in error. Set initial
2788 -- expression as absent (but do not make above complaints)
2790 elsif E = Error then
2791 Set_Expression (N, Empty);
2794 -- Case of initialization present
2797 -- Not allowed in Ada 83
2799 if not Constant_Present (N) then
2800 if Ada_Version = Ada_83
2801 and then Comes_From_Source (Object_Definition (N))
2804 ("(Ada 83) unconstrained variable not allowed",
2805 Object_Definition (N));
2809 -- Now we constrain the variable from the initializing expression
2811 -- If the expression is an aggregate, it has been expanded into
2812 -- individual assignments. Retrieve the actual type from the
2813 -- expanded construct.
2815 if Is_Array_Type (T)
2816 and then No_Initialization (N)
2817 and then Nkind (Original_Node (E)) = N_Aggregate
2821 -- In case of class-wide interface object declarations we delay
2822 -- the generation of the equivalent record type declarations until
2823 -- its expansion because there are cases in they are not required.
2825 elsif Is_Interface (T) then
2829 Expand_Subtype_From_Expr (N, T, Object_Definition (N), E);
2830 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
2833 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
2835 if Aliased_Present (N) then
2836 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
2839 Freeze_Before (N, Act_T);
2840 Freeze_Before (N, T);
2843 elsif Is_Array_Type (T)
2844 and then No_Initialization (N)
2845 and then Nkind (Original_Node (E)) = N_Aggregate
2847 if not Is_Entity_Name (Object_Definition (N)) then
2849 Check_Compile_Time_Size (Act_T);
2851 if Aliased_Present (N) then
2852 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
2856 -- When the given object definition and the aggregate are specified
2857 -- independently, and their lengths might differ do a length check.
2858 -- This cannot happen if the aggregate is of the form (others =>...)
2860 if not Is_Constrained (T) then
2863 elsif Nkind (E) = N_Raise_Constraint_Error then
2865 -- Aggregate is statically illegal. Place back in declaration
2867 Set_Expression (N, E);
2868 Set_No_Initialization (N, False);
2870 elsif T = Etype (E) then
2873 elsif Nkind (E) = N_Aggregate
2874 and then Present (Component_Associations (E))
2875 and then Present (Choices (First (Component_Associations (E))))
2876 and then Nkind (First
2877 (Choices (First (Component_Associations (E))))) = N_Others_Choice
2882 Apply_Length_Check (E, T);
2885 -- If the type is limited unconstrained with defaulted discriminants and
2886 -- there is no expression, then the object is constrained by the
2887 -- defaults, so it is worthwhile building the corresponding subtype.
2889 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
2890 and then not Is_Constrained (T)
2891 and then Has_Discriminants (T)
2894 Act_T := Build_Default_Subtype (T, N);
2896 -- Ada 2005: a limited object may be initialized by means of an
2897 -- aggregate. If the type has default discriminants it has an
2898 -- unconstrained nominal type, Its actual subtype will be obtained
2899 -- from the aggregate, and not from the default discriminants.
2904 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
2906 elsif Present (Underlying_Type (T))
2907 and then not Is_Constrained (Underlying_Type (T))
2908 and then Has_Discriminants (Underlying_Type (T))
2909 and then Nkind (E) = N_Function_Call
2910 and then Constant_Present (N)
2912 -- The back-end has problems with constants of a discriminated type
2913 -- with defaults, if the initial value is a function call. We
2914 -- generate an intermediate temporary for the result of the call.
2915 -- It is unclear why this should make it acceptable to gcc. ???
2917 Remove_Side_Effects (E);
2920 -- Check No_Wide_Characters restriction
2922 if T = Standard_Wide_Character
2923 or else T = Standard_Wide_Wide_Character
2924 or else Root_Type (T) = Standard_Wide_String
2925 or else Root_Type (T) = Standard_Wide_Wide_String
2927 Check_Restriction (No_Wide_Characters, Object_Definition (N));
2930 -- Indicate this is not set in source. Certainly true for constants,
2931 -- and true for variables so far (will be reset for a variable if and
2932 -- when we encounter a modification in the source).
2934 Set_Never_Set_In_Source (Id, True);
2936 -- Now establish the proper kind and type of the object
2938 if Constant_Present (N) then
2939 Set_Ekind (Id, E_Constant);
2940 Set_Is_True_Constant (Id, True);
2943 Set_Ekind (Id, E_Variable);
2945 -- A variable is set as shared passive if it appears in a shared
2946 -- passive package, and is at the outer level. This is not done
2947 -- for entities generated during expansion, because those are
2948 -- always manipulated locally.
2950 if Is_Shared_Passive (Current_Scope)
2951 and then Is_Library_Level_Entity (Id)
2952 and then Comes_From_Source (Id)
2954 Set_Is_Shared_Passive (Id);
2955 Check_Shared_Var (Id, T, N);
2958 -- Set Has_Initial_Value if initializing expression present. Note
2959 -- that if there is no initializing expression, we leave the state
2960 -- of this flag unchanged (usually it will be False, but notably in
2961 -- the case of exception choice variables, it will already be true).
2964 Set_Has_Initial_Value (Id, True);
2968 -- Initialize alignment and size and capture alignment setting
2970 Init_Alignment (Id);
2972 Set_Optimize_Alignment_Flags (Id);
2974 -- Deal with aliased case
2976 if Aliased_Present (N) then
2977 Set_Is_Aliased (Id);
2979 -- If the object is aliased and the type is unconstrained with
2980 -- defaulted discriminants and there is no expression, then the
2981 -- object is constrained by the defaults, so it is worthwhile
2982 -- building the corresponding subtype.
2984 -- Ada 2005 (AI-363): If the aliased object is discriminated and
2985 -- unconstrained, then only establish an actual subtype if the
2986 -- nominal subtype is indefinite. In definite cases the object is
2987 -- unconstrained in Ada 2005.
2990 and then Is_Record_Type (T)
2991 and then not Is_Constrained (T)
2992 and then Has_Discriminants (T)
2993 and then (Ada_Version < Ada_05 or else Is_Indefinite_Subtype (T))
2995 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
2999 -- Now we can set the type of the object
3001 Set_Etype (Id, Act_T);
3003 -- Deal with controlled types
3005 if Has_Controlled_Component (Etype (Id))
3006 or else Is_Controlled (Etype (Id))
3008 if not Is_Library_Level_Entity (Id) then
3009 Check_Restriction (No_Nested_Finalization, N);
3011 Validate_Controlled_Object (Id);
3014 -- Generate a warning when an initialization causes an obvious ABE
3015 -- violation. If the init expression is a simple aggregate there
3016 -- shouldn't be any initialize/adjust call generated. This will be
3017 -- true as soon as aggregates are built in place when possible.
3019 -- ??? at the moment we do not generate warnings for temporaries
3020 -- created for those aggregates although Program_Error might be
3021 -- generated if compiled with -gnato.
3023 if Is_Controlled (Etype (Id))
3024 and then Comes_From_Source (Id)
3027 BT : constant Entity_Id := Base_Type (Etype (Id));
3029 Implicit_Call : Entity_Id;
3030 pragma Warnings (Off, Implicit_Call);
3031 -- ??? what is this for (never referenced!)
3033 function Is_Aggr (N : Node_Id) return Boolean;
3034 -- Check that N is an aggregate
3040 function Is_Aggr (N : Node_Id) return Boolean is
3042 case Nkind (Original_Node (N)) is
3043 when N_Aggregate | N_Extension_Aggregate =>
3046 when N_Qualified_Expression |
3048 N_Unchecked_Type_Conversion =>
3049 return Is_Aggr (Expression (Original_Node (N)));
3057 -- If no underlying type, we already are in an error situation.
3058 -- Do not try to add a warning since we do not have access to
3061 if No (Underlying_Type (BT)) then
3062 Implicit_Call := Empty;
3064 -- A generic type does not have usable primitive operators.
3065 -- Initialization calls are built for instances.
3067 elsif Is_Generic_Type (BT) then
3068 Implicit_Call := Empty;
3070 -- If the init expression is not an aggregate, an adjust call
3071 -- will be generated
3073 elsif Present (E) and then not Is_Aggr (E) then
3074 Implicit_Call := Find_Prim_Op (BT, Name_Adjust);
3076 -- If no init expression and we are not in the deferred
3077 -- constant case, an Initialize call will be generated
3079 elsif No (E) and then not Constant_Present (N) then
3080 Implicit_Call := Find_Prim_Op (BT, Name_Initialize);
3083 Implicit_Call := Empty;
3089 if Has_Task (Etype (Id)) then
3090 Check_Restriction (No_Tasking, N);
3092 -- Deal with counting max tasks
3094 -- Nothing to do if inside a generic
3096 if Inside_A_Generic then
3099 -- If library level entity, then count tasks
3101 elsif Is_Library_Level_Entity (Id) then
3102 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
3104 -- If not library level entity, then indicate we don't know max
3105 -- tasks and also check task hierarchy restriction and blocking
3106 -- operation (since starting a task is definitely blocking!)
3109 Check_Restriction (Max_Tasks, N);
3110 Check_Restriction (No_Task_Hierarchy, N);
3111 Check_Potentially_Blocking_Operation (N);
3114 -- A rather specialized test. If we see two tasks being declared
3115 -- of the same type in the same object declaration, and the task
3116 -- has an entry with an address clause, we know that program error
3117 -- will be raised at run-time since we can't have two tasks with
3118 -- entries at the same address.
3120 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
3125 E := First_Entity (Etype (Id));
3126 while Present (E) loop
3127 if Ekind (E) = E_Entry
3128 and then Present (Get_Attribute_Definition_Clause
3129 (E, Attribute_Address))
3132 ("?more than one task with same entry address", N);
3134 ("\?Program_Error will be raised at run time", N);
3136 Make_Raise_Program_Error (Loc,
3137 Reason => PE_Duplicated_Entry_Address));
3147 -- Some simple constant-propagation: if the expression is a constant
3148 -- string initialized with a literal, share the literal. This avoids
3152 and then Is_Entity_Name (E)
3153 and then Ekind (Entity (E)) = E_Constant
3154 and then Base_Type (Etype (E)) = Standard_String
3157 Val : constant Node_Id := Constant_Value (Entity (E));
3160 and then Nkind (Val) = N_String_Literal
3162 Rewrite (E, New_Copy (Val));
3167 -- Another optimization: if the nominal subtype is unconstrained and
3168 -- the expression is a function call that returns an unconstrained
3169 -- type, rewrite the declaration as a renaming of the result of the
3170 -- call. The exceptions below are cases where the copy is expected,
3171 -- either by the back end (Aliased case) or by the semantics, as for
3172 -- initializing controlled types or copying tags for classwide types.
3175 and then Nkind (E) = N_Explicit_Dereference
3176 and then Nkind (Original_Node (E)) = N_Function_Call
3177 and then not Is_Library_Level_Entity (Id)
3178 and then not Is_Constrained (Underlying_Type (T))
3179 and then not Is_Aliased (Id)
3180 and then not Is_Class_Wide_Type (T)
3181 and then not Is_Controlled (T)
3182 and then not Has_Controlled_Component (Base_Type (T))
3183 and then Expander_Active
3186 Make_Object_Renaming_Declaration (Loc,
3187 Defining_Identifier => Id,
3188 Access_Definition => Empty,
3189 Subtype_Mark => New_Occurrence_Of
3190 (Base_Type (Etype (Id)), Loc),
3193 Set_Renamed_Object (Id, E);
3195 -- Force generation of debugging information for the constant and for
3196 -- the renamed function call.
3198 Set_Debug_Info_Needed (Id);
3199 Set_Debug_Info_Needed (Entity (Prefix (E)));
3202 if Present (Prev_Entity)
3203 and then Is_Frozen (Prev_Entity)
3204 and then not Error_Posted (Id)
3206 Error_Msg_N ("full constant declaration appears too late", N);
3209 Check_Eliminated (Id);
3211 -- Deal with setting In_Private_Part flag if in private part
3213 if Ekind (Scope (Id)) = E_Package
3214 and then In_Private_Part (Scope (Id))
3216 Set_In_Private_Part (Id);
3219 -- Check for violation of No_Local_Timing_Events
3221 if Is_RTE (Etype (Id), RE_Timing_Event)
3222 and then not Is_Library_Level_Entity (Id)
3224 Check_Restriction (No_Local_Timing_Events, N);
3226 end Analyze_Object_Declaration;
3228 ---------------------------
3229 -- Analyze_Others_Choice --
3230 ---------------------------
3232 -- Nothing to do for the others choice node itself, the semantic analysis
3233 -- of the others choice will occur as part of the processing of the parent
3235 procedure Analyze_Others_Choice (N : Node_Id) is
3236 pragma Warnings (Off, N);
3239 end Analyze_Others_Choice;
3241 -------------------------------------------
3242 -- Analyze_Private_Extension_Declaration --
3243 -------------------------------------------
3245 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
3246 T : constant Entity_Id := Defining_Identifier (N);
3247 Indic : constant Node_Id := Subtype_Indication (N);
3248 Parent_Type : Entity_Id;
3249 Parent_Base : Entity_Id;
3252 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
3254 if Is_Non_Empty_List (Interface_List (N)) then
3260 Intf := First (Interface_List (N));
3261 while Present (Intf) loop
3262 T := Find_Type_Of_Subtype_Indic (Intf);
3264 Diagnose_Interface (Intf, T);
3270 Generate_Definition (T);
3273 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
3274 Parent_Base := Base_Type (Parent_Type);
3276 if Parent_Type = Any_Type
3277 or else Etype (Parent_Type) = Any_Type
3279 Set_Ekind (T, Ekind (Parent_Type));
3280 Set_Etype (T, Any_Type);
3283 elsif not Is_Tagged_Type (Parent_Type) then
3285 ("parent of type extension must be a tagged type ", Indic);
3288 elsif Ekind (Parent_Type) = E_Void
3289 or else Ekind (Parent_Type) = E_Incomplete_Type
3291 Error_Msg_N ("premature derivation of incomplete type", Indic);
3294 elsif Is_Concurrent_Type (Parent_Type) then
3296 ("parent type of a private extension cannot be "
3297 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
3299 Set_Etype (T, Any_Type);
3300 Set_Ekind (T, E_Limited_Private_Type);
3301 Set_Private_Dependents (T, New_Elmt_List);
3302 Set_Error_Posted (T);
3306 -- Perhaps the parent type should be changed to the class-wide type's
3307 -- specific type in this case to prevent cascading errors ???
3309 if Is_Class_Wide_Type (Parent_Type) then
3311 ("parent of type extension must not be a class-wide type", Indic);
3315 if (not Is_Package_Or_Generic_Package (Current_Scope)
3316 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
3317 or else In_Private_Part (Current_Scope)
3320 Error_Msg_N ("invalid context for private extension", N);
3323 -- Set common attributes
3325 Set_Is_Pure (T, Is_Pure (Current_Scope));
3326 Set_Scope (T, Current_Scope);
3327 Set_Ekind (T, E_Record_Type_With_Private);
3328 Init_Size_Align (T);
3330 Set_Etype (T, Parent_Base);
3331 Set_Has_Task (T, Has_Task (Parent_Base));
3333 Set_Convention (T, Convention (Parent_Type));
3334 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
3335 Set_Is_First_Subtype (T);
3336 Make_Class_Wide_Type (T);
3338 if Unknown_Discriminants_Present (N) then
3339 Set_Discriminant_Constraint (T, No_Elist);
3342 Build_Derived_Record_Type (N, Parent_Type, T);
3344 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
3345 -- synchronized formal derived type.
3347 if Ada_Version >= Ada_05
3348 and then Synchronized_Present (N)
3350 Set_Is_Limited_Record (T);
3352 -- Formal derived type case
3354 if Is_Generic_Type (T) then
3356 -- The parent must be a tagged limited type or a synchronized
3359 if (not Is_Tagged_Type (Parent_Type)
3360 or else not Is_Limited_Type (Parent_Type))
3362 (not Is_Interface (Parent_Type)
3363 or else not Is_Synchronized_Interface (Parent_Type))
3365 Error_Msg_NE ("parent type of & must be tagged limited " &
3366 "or synchronized", N, T);
3369 -- The progenitors (if any) must be limited or synchronized
3372 if Present (Interfaces (T)) then
3375 Iface_Elmt : Elmt_Id;
3378 Iface_Elmt := First_Elmt (Interfaces (T));
3379 while Present (Iface_Elmt) loop
3380 Iface := Node (Iface_Elmt);
3382 if not Is_Limited_Interface (Iface)
3383 and then not Is_Synchronized_Interface (Iface)
3385 Error_Msg_NE ("progenitor & must be limited " &
3386 "or synchronized", N, Iface);
3389 Next_Elmt (Iface_Elmt);
3394 -- Regular derived extension, the parent must be a limited or
3395 -- synchronized interface.
3398 if not Is_Interface (Parent_Type)
3399 or else (not Is_Limited_Interface (Parent_Type)
3401 not Is_Synchronized_Interface (Parent_Type))
3404 ("parent type of & must be limited interface", N, T);
3408 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
3409 -- extension with a synchronized parent must be explicitly declared
3410 -- synchronized, because the full view will be a synchronized type.
3411 -- This must be checked before the check for limited types below,
3412 -- to ensure that types declared limited are not allowed to extend
3413 -- synchronized interfaces.
3415 elsif Is_Interface (Parent_Type)
3416 and then Is_Synchronized_Interface (Parent_Type)
3417 and then not Synchronized_Present (N)
3420 ("private extension of& must be explicitly synchronized",
3423 elsif Limited_Present (N) then
3424 Set_Is_Limited_Record (T);
3426 if not Is_Limited_Type (Parent_Type)
3428 (not Is_Interface (Parent_Type)
3429 or else not Is_Limited_Interface (Parent_Type))
3431 Error_Msg_NE ("parent type& of limited extension must be limited",
3435 end Analyze_Private_Extension_Declaration;
3437 ---------------------------------
3438 -- Analyze_Subtype_Declaration --
3439 ---------------------------------
3441 procedure Analyze_Subtype_Declaration
3443 Skip : Boolean := False)
3445 Id : constant Entity_Id := Defining_Identifier (N);
3447 R_Checks : Check_Result;
3450 Generate_Definition (Id);
3451 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3452 Init_Size_Align (Id);
3454 -- The following guard condition on Enter_Name is to handle cases where
3455 -- the defining identifier has already been entered into the scope but
3456 -- the declaration as a whole needs to be analyzed.
3458 -- This case in particular happens for derived enumeration types. The
3459 -- derived enumeration type is processed as an inserted enumeration type
3460 -- declaration followed by a rewritten subtype declaration. The defining
3461 -- identifier, however, is entered into the name scope very early in the
3462 -- processing of the original type declaration and therefore needs to be
3463 -- avoided here, when the created subtype declaration is analyzed. (See
3464 -- Build_Derived_Types)
3466 -- This also happens when the full view of a private type is derived
3467 -- type with constraints. In this case the entity has been introduced
3468 -- in the private declaration.
3471 or else (Present (Etype (Id))
3472 and then (Is_Private_Type (Etype (Id))
3473 or else Is_Task_Type (Etype (Id))
3474 or else Is_Rewrite_Substitution (N)))
3482 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
3484 -- Inherit common attributes
3486 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
3487 Set_Is_Volatile (Id, Is_Volatile (T));
3488 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
3489 Set_Is_Atomic (Id, Is_Atomic (T));
3490 Set_Is_Ada_2005_Only (Id, Is_Ada_2005_Only (T));
3491 Set_Convention (Id, Convention (T));
3493 -- In the case where there is no constraint given in the subtype
3494 -- indication, Process_Subtype just returns the Subtype_Mark, so its
3495 -- semantic attributes must be established here.
3497 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
3498 Set_Etype (Id, Base_Type (T));
3502 Set_Ekind (Id, E_Array_Subtype);
3503 Copy_Array_Subtype_Attributes (Id, T);
3505 when Decimal_Fixed_Point_Kind =>
3506 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
3507 Set_Digits_Value (Id, Digits_Value (T));
3508 Set_Delta_Value (Id, Delta_Value (T));
3509 Set_Scale_Value (Id, Scale_Value (T));
3510 Set_Small_Value (Id, Small_Value (T));
3511 Set_Scalar_Range (Id, Scalar_Range (T));
3512 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
3513 Set_Is_Constrained (Id, Is_Constrained (T));
3514 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
3515 Set_RM_Size (Id, RM_Size (T));
3517 when Enumeration_Kind =>
3518 Set_Ekind (Id, E_Enumeration_Subtype);
3519 Set_First_Literal (Id, First_Literal (Base_Type (T)));
3520 Set_Scalar_Range (Id, Scalar_Range (T));
3521 Set_Is_Character_Type (Id, Is_Character_Type (T));
3522 Set_Is_Constrained (Id, Is_Constrained (T));
3523 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
3524 Set_RM_Size (Id, RM_Size (T));
3526 when Ordinary_Fixed_Point_Kind =>
3527 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
3528 Set_Scalar_Range (Id, Scalar_Range (T));
3529 Set_Small_Value (Id, Small_Value (T));
3530 Set_Delta_Value (Id, Delta_Value (T));
3531 Set_Is_Constrained (Id, Is_Constrained (T));
3532 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
3533 Set_RM_Size (Id, RM_Size (T));
3536 Set_Ekind (Id, E_Floating_Point_Subtype);
3537 Set_Scalar_Range (Id, Scalar_Range (T));
3538 Set_Digits_Value (Id, Digits_Value (T));
3539 Set_Is_Constrained (Id, Is_Constrained (T));
3541 when Signed_Integer_Kind =>
3542 Set_Ekind (Id, E_Signed_Integer_Subtype);
3543 Set_Scalar_Range (Id, Scalar_Range (T));
3544 Set_Is_Constrained (Id, Is_Constrained (T));
3545 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
3546 Set_RM_Size (Id, RM_Size (T));
3548 when Modular_Integer_Kind =>
3549 Set_Ekind (Id, E_Modular_Integer_Subtype);
3550 Set_Scalar_Range (Id, Scalar_Range (T));
3551 Set_Is_Constrained (Id, Is_Constrained (T));
3552 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
3553 Set_RM_Size (Id, RM_Size (T));
3555 when Class_Wide_Kind =>
3556 Set_Ekind (Id, E_Class_Wide_Subtype);
3557 Set_First_Entity (Id, First_Entity (T));
3558 Set_Last_Entity (Id, Last_Entity (T));
3559 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
3560 Set_Cloned_Subtype (Id, T);
3561 Set_Is_Tagged_Type (Id, True);
3562 Set_Has_Unknown_Discriminants
3565 if Ekind (T) = E_Class_Wide_Subtype then
3566 Set_Equivalent_Type (Id, Equivalent_Type (T));
3569 when E_Record_Type | E_Record_Subtype =>
3570 Set_Ekind (Id, E_Record_Subtype);
3572 if Ekind (T) = E_Record_Subtype
3573 and then Present (Cloned_Subtype (T))
3575 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
3577 Set_Cloned_Subtype (Id, T);
3580 Set_First_Entity (Id, First_Entity (T));
3581 Set_Last_Entity (Id, Last_Entity (T));
3582 Set_Has_Discriminants (Id, Has_Discriminants (T));
3583 Set_Is_Constrained (Id, Is_Constrained (T));
3584 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
3585 Set_Has_Unknown_Discriminants
3586 (Id, Has_Unknown_Discriminants (T));
3588 if Has_Discriminants (T) then
3589 Set_Discriminant_Constraint
3590 (Id, Discriminant_Constraint (T));
3591 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
3593 elsif Has_Unknown_Discriminants (Id) then
3594 Set_Discriminant_Constraint (Id, No_Elist);
3597 if Is_Tagged_Type (T) then
3598 Set_Is_Tagged_Type (Id);
3599 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
3600 Set_Primitive_Operations
3601 (Id, Primitive_Operations (T));
3602 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
3604 if Is_Interface (T) then
3605 Set_Is_Interface (Id);
3606 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
3610 when Private_Kind =>
3611 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
3612 Set_Has_Discriminants (Id, Has_Discriminants (T));
3613 Set_Is_Constrained (Id, Is_Constrained (T));
3614 Set_First_Entity (Id, First_Entity (T));
3615 Set_Last_Entity (Id, Last_Entity (T));
3616 Set_Private_Dependents (Id, New_Elmt_List);
3617 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
3618 Set_Has_Unknown_Discriminants
3619 (Id, Has_Unknown_Discriminants (T));
3620 Set_Known_To_Have_Preelab_Init
3621 (Id, Known_To_Have_Preelab_Init (T));
3623 if Is_Tagged_Type (T) then
3624 Set_Is_Tagged_Type (Id);
3625 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
3626 Set_Primitive_Operations (Id, Primitive_Operations (T));
3627 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
3630 -- In general the attributes of the subtype of a private type
3631 -- are the attributes of the partial view of parent. However,
3632 -- the full view may be a discriminated type, and the subtype
3633 -- must share the discriminant constraint to generate correct
3634 -- calls to initialization procedures.
3636 if Has_Discriminants (T) then
3637 Set_Discriminant_Constraint
3638 (Id, Discriminant_Constraint (T));
3639 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
3641 elsif Present (Full_View (T))
3642 and then Has_Discriminants (Full_View (T))
3644 Set_Discriminant_Constraint
3645 (Id, Discriminant_Constraint (Full_View (T)));
3646 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
3648 -- This would seem semantically correct, but apparently
3649 -- confuses the back-end. To be explained and checked with
3650 -- current version ???
3652 -- Set_Has_Discriminants (Id);
3655 Prepare_Private_Subtype_Completion (Id, N);
3658 Set_Ekind (Id, E_Access_Subtype);
3659 Set_Is_Constrained (Id, Is_Constrained (T));
3660 Set_Is_Access_Constant
3661 (Id, Is_Access_Constant (T));
3662 Set_Directly_Designated_Type
3663 (Id, Designated_Type (T));
3664 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
3666 -- A Pure library_item must not contain the declaration of a
3667 -- named access type, except within a subprogram, generic
3668 -- subprogram, task unit, or protected unit, or if it has
3669 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
3671 if Comes_From_Source (Id)
3672 and then In_Pure_Unit
3673 and then not In_Subprogram_Task_Protected_Unit
3674 and then not No_Pool_Assigned (Id)
3677 ("named access types not allowed in pure unit", N);
3680 when Concurrent_Kind =>
3681 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
3682 Set_Corresponding_Record_Type (Id,
3683 Corresponding_Record_Type (T));
3684 Set_First_Entity (Id, First_Entity (T));
3685 Set_First_Private_Entity (Id, First_Private_Entity (T));
3686 Set_Has_Discriminants (Id, Has_Discriminants (T));
3687 Set_Is_Constrained (Id, Is_Constrained (T));
3688 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
3689 Set_Last_Entity (Id, Last_Entity (T));
3691 if Has_Discriminants (T) then
3692 Set_Discriminant_Constraint (Id,
3693 Discriminant_Constraint (T));
3694 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
3697 when E_Incomplete_Type =>
3698 if Ada_Version >= Ada_05 then
3699 Set_Ekind (Id, E_Incomplete_Subtype);
3701 -- Ada 2005 (AI-412): Decorate an incomplete subtype
3702 -- of an incomplete type visible through a limited
3705 if From_With_Type (T)
3706 and then Present (Non_Limited_View (T))
3708 Set_From_With_Type (Id);
3709 Set_Non_Limited_View (Id, Non_Limited_View (T));
3711 -- Ada 2005 (AI-412): Add the regular incomplete subtype
3712 -- to the private dependents of the original incomplete
3713 -- type for future transformation.
3716 Append_Elmt (Id, Private_Dependents (T));
3719 -- If the subtype name denotes an incomplete type an error
3720 -- was already reported by Process_Subtype.
3723 Set_Etype (Id, Any_Type);
3727 raise Program_Error;
3731 if Etype (Id) = Any_Type then
3735 -- Some common processing on all types
3737 Set_Size_Info (Id, T);
3738 Set_First_Rep_Item (Id, First_Rep_Item (T));
3742 Set_Is_Immediately_Visible (Id, True);
3743 Set_Depends_On_Private (Id, Has_Private_Component (T));
3744 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
3746 if Is_Interface (T) then
3747 Set_Is_Interface (Id);
3750 if Present (Generic_Parent_Type (N))
3753 (Parent (Generic_Parent_Type (N))) /= N_Formal_Type_Declaration
3755 (Formal_Type_Definition (Parent (Generic_Parent_Type (N))))
3756 /= N_Formal_Private_Type_Definition)
3758 if Is_Tagged_Type (Id) then
3760 -- If this is a generic actual subtype for a synchronized type,
3761 -- the primitive operations are those of the corresponding record
3762 -- for which there is a separate subtype declaration.
3764 if Is_Concurrent_Type (Id) then
3766 elsif Is_Class_Wide_Type (Id) then
3767 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
3769 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
3772 elsif Scope (Etype (Id)) /= Standard_Standard then
3773 Derive_Subprograms (Generic_Parent_Type (N), Id);
3777 if Is_Private_Type (T)
3778 and then Present (Full_View (T))
3780 Conditional_Delay (Id, Full_View (T));
3782 -- The subtypes of components or subcomponents of protected types
3783 -- do not need freeze nodes, which would otherwise appear in the
3784 -- wrong scope (before the freeze node for the protected type). The
3785 -- proper subtypes are those of the subcomponents of the corresponding
3788 elsif Ekind (Scope (Id)) /= E_Protected_Type
3789 and then Present (Scope (Scope (Id))) -- error defense!
3790 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
3792 Conditional_Delay (Id, T);
3795 -- Check that constraint_error is raised for a scalar subtype
3796 -- indication when the lower or upper bound of a non-null range
3797 -- lies outside the range of the type mark.
3799 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
3800 if Is_Scalar_Type (Etype (Id))
3801 and then Scalar_Range (Id) /=
3802 Scalar_Range (Etype (Subtype_Mark
3803 (Subtype_Indication (N))))
3807 Etype (Subtype_Mark (Subtype_Indication (N))));
3809 elsif Is_Array_Type (Etype (Id))
3810 and then Present (First_Index (Id))
3812 -- This really should be a subprogram that finds the indications
3815 if ((Nkind (First_Index (Id)) = N_Identifier
3816 and then Ekind (Entity (First_Index (Id))) in Scalar_Kind)
3817 or else Nkind (First_Index (Id)) = N_Subtype_Indication)
3819 Nkind (Scalar_Range (Etype (First_Index (Id)))) = N_Range
3822 Target_Typ : constant Entity_Id :=
3825 (Subtype_Mark (Subtype_Indication (N)))));
3829 (Scalar_Range (Etype (First_Index (Id))),
3831 Etype (First_Index (Id)),
3832 Defining_Identifier (N));
3838 Sloc (Defining_Identifier (N)));
3844 Set_Optimize_Alignment_Flags (Id);
3845 Check_Eliminated (Id);
3846 end Analyze_Subtype_Declaration;
3848 --------------------------------
3849 -- Analyze_Subtype_Indication --
3850 --------------------------------
3852 procedure Analyze_Subtype_Indication (N : Node_Id) is
3853 T : constant Entity_Id := Subtype_Mark (N);
3854 R : constant Node_Id := Range_Expression (Constraint (N));
3861 Set_Etype (N, Etype (R));
3862 Resolve (R, Entity (T));
3864 Set_Error_Posted (R);
3865 Set_Error_Posted (T);
3867 end Analyze_Subtype_Indication;
3869 ------------------------------
3870 -- Analyze_Type_Declaration --
3871 ------------------------------
3873 procedure Analyze_Type_Declaration (N : Node_Id) is
3874 Def : constant Node_Id := Type_Definition (N);
3875 Def_Id : constant Entity_Id := Defining_Identifier (N);
3879 Is_Remote : constant Boolean :=
3880 (Is_Remote_Types (Current_Scope)
3881 or else Is_Remote_Call_Interface (Current_Scope))
3882 and then not (In_Private_Part (Current_Scope)
3883 or else In_Package_Body (Current_Scope));
3885 procedure Check_Ops_From_Incomplete_Type;
3886 -- If there is a tagged incomplete partial view of the type, transfer
3887 -- its operations to the full view, and indicate that the type of the
3888 -- controlling parameter (s) is this full view.
3890 ------------------------------------
3891 -- Check_Ops_From_Incomplete_Type --
3892 ------------------------------------
3894 procedure Check_Ops_From_Incomplete_Type is
3901 and then Ekind (Prev) = E_Incomplete_Type
3902 and then Is_Tagged_Type (Prev)
3903 and then Is_Tagged_Type (T)
3905 Elmt := First_Elmt (Primitive_Operations (Prev));
3906 while Present (Elmt) loop
3908 Prepend_Elmt (Op, Primitive_Operations (T));
3910 Formal := First_Formal (Op);
3911 while Present (Formal) loop
3912 if Etype (Formal) = Prev then
3913 Set_Etype (Formal, T);
3916 Next_Formal (Formal);
3919 if Etype (Op) = Prev then
3926 end Check_Ops_From_Incomplete_Type;
3928 -- Start of processing for Analyze_Type_Declaration
3931 Prev := Find_Type_Name (N);
3933 -- The full view, if present, now points to the current type
3935 -- Ada 2005 (AI-50217): If the type was previously decorated when
3936 -- imported through a LIMITED WITH clause, it appears as incomplete
3937 -- but has no full view.
3938 -- If the incomplete view is tagged, a class_wide type has been
3939 -- created already. Use it for the full view as well, to prevent
3940 -- multiple incompatible class-wide types that may be created for
3941 -- self-referential anonymous access components.
3943 if Ekind (Prev) = E_Incomplete_Type
3944 and then Present (Full_View (Prev))
3946 T := Full_View (Prev);
3948 if Is_Tagged_Type (Prev)
3949 and then Present (Class_Wide_Type (Prev))
3951 Set_Ekind (T, Ekind (Prev)); -- will be reset later
3952 Set_Class_Wide_Type (T, Class_Wide_Type (Prev));
3953 Set_Etype (Class_Wide_Type (T), T);
3960 Set_Is_Pure (T, Is_Pure (Current_Scope));
3962 -- We set the flag Is_First_Subtype here. It is needed to set the
3963 -- corresponding flag for the Implicit class-wide-type created
3964 -- during tagged types processing.
3966 Set_Is_First_Subtype (T, True);
3968 -- Only composite types other than array types are allowed to have
3973 -- For derived types, the rule will be checked once we've figured
3974 -- out the parent type.
3976 when N_Derived_Type_Definition =>
3979 -- For record types, discriminants are allowed
3981 when N_Record_Definition =>
3985 if Present (Discriminant_Specifications (N)) then
3987 ("elementary or array type cannot have discriminants",
3989 (First (Discriminant_Specifications (N))));
3993 -- Elaborate the type definition according to kind, and generate
3994 -- subsidiary (implicit) subtypes where needed. We skip this if it was
3995 -- already done (this happens during the reanalysis that follows a call
3996 -- to the high level optimizer).
3998 if not Analyzed (T) then
4003 when N_Access_To_Subprogram_Definition =>
4004 Access_Subprogram_Declaration (T, Def);
4006 -- If this is a remote access to subprogram, we must create the
4007 -- equivalent fat pointer type, and related subprograms.
4010 Process_Remote_AST_Declaration (N);
4013 -- Validate categorization rule against access type declaration
4014 -- usually a violation in Pure unit, Shared_Passive unit.
4016 Validate_Access_Type_Declaration (T, N);
4018 when N_Access_To_Object_Definition =>
4019 Access_Type_Declaration (T, Def);
4021 -- Validate categorization rule against access type declaration
4022 -- usually a violation in Pure unit, Shared_Passive unit.
4024 Validate_Access_Type_Declaration (T, N);
4026 -- If we are in a Remote_Call_Interface package and define a
4027 -- RACW, then calling stubs and specific stream attributes
4031 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
4033 Add_RACW_Features (Def_Id);
4036 -- Set no strict aliasing flag if config pragma seen
4038 if Opt.No_Strict_Aliasing then
4039 Set_No_Strict_Aliasing (Base_Type (Def_Id));
4042 when N_Array_Type_Definition =>
4043 Array_Type_Declaration (T, Def);
4045 when N_Derived_Type_Definition =>
4046 Derived_Type_Declaration (T, N, T /= Def_Id);
4048 when N_Enumeration_Type_Definition =>
4049 Enumeration_Type_Declaration (T, Def);
4051 when N_Floating_Point_Definition =>
4052 Floating_Point_Type_Declaration (T, Def);
4054 when N_Decimal_Fixed_Point_Definition =>
4055 Decimal_Fixed_Point_Type_Declaration (T, Def);
4057 when N_Ordinary_Fixed_Point_Definition =>
4058 Ordinary_Fixed_Point_Type_Declaration (T, Def);
4060 when N_Signed_Integer_Type_Definition =>
4061 Signed_Integer_Type_Declaration (T, Def);
4063 when N_Modular_Type_Definition =>
4064 Modular_Type_Declaration (T, Def);
4066 when N_Record_Definition =>
4067 Record_Type_Declaration (T, N, Prev);
4070 raise Program_Error;
4075 if Etype (T) = Any_Type then
4079 -- Some common processing for all types
4081 Set_Depends_On_Private (T, Has_Private_Component (T));
4082 Check_Ops_From_Incomplete_Type;
4084 -- Both the declared entity, and its anonymous base type if one
4085 -- was created, need freeze nodes allocated.
4088 B : constant Entity_Id := Base_Type (T);
4091 -- In the case where the base type differs from the first subtype, we
4092 -- pre-allocate a freeze node, and set the proper link to the first
4093 -- subtype. Freeze_Entity will use this preallocated freeze node when
4094 -- it freezes the entity.
4096 -- This does not apply if the base type is a generic type, whose
4097 -- declaration is independent of the current derived definition.
4099 if B /= T and then not Is_Generic_Type (B) then
4100 Ensure_Freeze_Node (B);
4101 Set_First_Subtype_Link (Freeze_Node (B), T);
4104 -- A type that is imported through a limited_with clause cannot
4105 -- generate any code, and thus need not be frozen. However, an access
4106 -- type with an imported designated type needs a finalization list,
4107 -- which may be referenced in some other package that has non-limited
4108 -- visibility on the designated type. Thus we must create the
4109 -- finalization list at the point the access type is frozen, to
4110 -- prevent unsatisfied references at link time.
4112 if not From_With_Type (T) or else Is_Access_Type (T) then
4113 Set_Has_Delayed_Freeze (T);
4117 -- Case where T is the full declaration of some private type which has
4118 -- been swapped in Defining_Identifier (N).
4120 if T /= Def_Id and then Is_Private_Type (Def_Id) then
4121 Process_Full_View (N, T, Def_Id);
4123 -- Record the reference. The form of this is a little strange, since
4124 -- the full declaration has been swapped in. So the first parameter
4125 -- here represents the entity to which a reference is made which is
4126 -- the "real" entity, i.e. the one swapped in, and the second
4127 -- parameter provides the reference location.
4129 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
4130 -- since we don't want a complaint about the full type being an
4131 -- unwanted reference to the private type
4134 B : constant Boolean := Has_Pragma_Unreferenced (T);
4136 Set_Has_Pragma_Unreferenced (T, False);
4137 Generate_Reference (T, T, 'c');
4138 Set_Has_Pragma_Unreferenced (T, B);
4141 Set_Completion_Referenced (Def_Id);
4143 -- For completion of incomplete type, process incomplete dependents
4144 -- and always mark the full type as referenced (it is the incomplete
4145 -- type that we get for any real reference).
4147 elsif Ekind (Prev) = E_Incomplete_Type then
4148 Process_Incomplete_Dependents (N, T, Prev);
4149 Generate_Reference (Prev, Def_Id, 'c');
4150 Set_Completion_Referenced (Def_Id);
4152 -- If not private type or incomplete type completion, this is a real
4153 -- definition of a new entity, so record it.
4156 Generate_Definition (Def_Id);
4159 if Chars (Scope (Def_Id)) = Name_System
4160 and then Chars (Def_Id) = Name_Address
4161 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
4163 Set_Is_Descendent_Of_Address (Def_Id);
4164 Set_Is_Descendent_Of_Address (Base_Type (Def_Id));
4165 Set_Is_Descendent_Of_Address (Prev);
4168 Set_Optimize_Alignment_Flags (Def_Id);
4169 Check_Eliminated (Def_Id);
4170 end Analyze_Type_Declaration;
4172 --------------------------
4173 -- Analyze_Variant_Part --
4174 --------------------------
4176 procedure Analyze_Variant_Part (N : Node_Id) is
4178 procedure Non_Static_Choice_Error (Choice : Node_Id);
4179 -- Error routine invoked by the generic instantiation below when the
4180 -- variant part has a non static choice.
4182 procedure Process_Declarations (Variant : Node_Id);
4183 -- Analyzes all the declarations associated with a Variant. Needed by
4184 -- the generic instantiation below.
4186 package Variant_Choices_Processing is new
4187 Generic_Choices_Processing
4188 (Get_Alternatives => Variants,
4189 Get_Choices => Discrete_Choices,
4190 Process_Empty_Choice => No_OP,
4191 Process_Non_Static_Choice => Non_Static_Choice_Error,
4192 Process_Associated_Node => Process_Declarations);
4193 use Variant_Choices_Processing;
4194 -- Instantiation of the generic choice processing package
4196 -----------------------------
4197 -- Non_Static_Choice_Error --
4198 -----------------------------
4200 procedure Non_Static_Choice_Error (Choice : Node_Id) is
4202 Flag_Non_Static_Expr
4203 ("choice given in variant part is not static!", Choice);
4204 end Non_Static_Choice_Error;
4206 --------------------------
4207 -- Process_Declarations --
4208 --------------------------
4210 procedure Process_Declarations (Variant : Node_Id) is
4212 if not Null_Present (Component_List (Variant)) then
4213 Analyze_Declarations (Component_Items (Component_List (Variant)));
4215 if Present (Variant_Part (Component_List (Variant))) then
4216 Analyze (Variant_Part (Component_List (Variant)));
4219 end Process_Declarations;
4223 Discr_Name : Node_Id;
4224 Discr_Type : Entity_Id;
4226 Case_Table : Choice_Table_Type (1 .. Number_Of_Choices (N));
4228 Dont_Care : Boolean;
4229 Others_Present : Boolean := False;
4231 pragma Warnings (Off, Case_Table);
4232 pragma Warnings (Off, Last_Choice);
4233 pragma Warnings (Off, Dont_Care);
4234 pragma Warnings (Off, Others_Present);
4235 -- We don't care about the assigned values of any of these
4237 -- Start of processing for Analyze_Variant_Part
4240 Discr_Name := Name (N);
4241 Analyze (Discr_Name);
4243 -- If Discr_Name bad, get out (prevent cascaded errors)
4245 if Etype (Discr_Name) = Any_Type then
4249 -- Check invalid discriminant in variant part
4251 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
4252 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
4255 Discr_Type := Etype (Entity (Discr_Name));
4257 if not Is_Discrete_Type (Discr_Type) then
4259 ("discriminant in a variant part must be of a discrete type",
4264 -- Call the instantiated Analyze_Choices which does the rest of the work
4267 (N, Discr_Type, Case_Table, Last_Choice, Dont_Care, Others_Present);
4268 end Analyze_Variant_Part;
4270 ----------------------------
4271 -- Array_Type_Declaration --
4272 ----------------------------
4274 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
4275 Component_Def : constant Node_Id := Component_Definition (Def);
4276 Element_Type : Entity_Id;
4277 Implicit_Base : Entity_Id;
4279 Related_Id : Entity_Id := Empty;
4281 P : constant Node_Id := Parent (Def);
4285 if Nkind (Def) = N_Constrained_Array_Definition then
4286 Index := First (Discrete_Subtype_Definitions (Def));
4288 Index := First (Subtype_Marks (Def));
4291 -- Find proper names for the implicit types which may be public. In case
4292 -- of anonymous arrays we use the name of the first object of that type
4296 Related_Id := Defining_Identifier (P);
4302 while Present (Index) loop
4305 -- Add a subtype declaration for each index of private array type
4306 -- declaration whose etype is also private. For example:
4309 -- type Index is private;
4311 -- type Table is array (Index) of ...
4314 -- This is currently required by the expander for the internally
4315 -- generated equality subprogram of records with variant parts in
4316 -- which the etype of some component is such private type.
4318 if Ekind (Current_Scope) = E_Package
4319 and then In_Private_Part (Current_Scope)
4320 and then Has_Private_Declaration (Etype (Index))
4323 Loc : constant Source_Ptr := Sloc (Def);
4329 Make_Defining_Identifier (Loc,
4330 Chars => New_Internal_Name ('T'));
4331 Set_Is_Internal (New_E);
4334 Make_Subtype_Declaration (Loc,
4335 Defining_Identifier => New_E,
4336 Subtype_Indication =>
4337 New_Occurrence_Of (Etype (Index), Loc));
4339 Insert_Before (Parent (Def), Decl);
4341 Set_Etype (Index, New_E);
4343 -- If the index is a range the Entity attribute is not
4344 -- available. Example:
4347 -- type T is private;
4349 -- type T is new Natural;
4350 -- Table : array (T(1) .. T(10)) of Boolean;
4353 if Nkind (Index) /= N_Range then
4354 Set_Entity (Index, New_E);
4359 Make_Index (Index, P, Related_Id, Nb_Index);
4361 Nb_Index := Nb_Index + 1;
4364 -- Process subtype indication if one is present
4366 if Present (Subtype_Indication (Component_Def)) then
4369 (Subtype_Indication (Component_Def), P, Related_Id, 'C');
4371 -- Ada 2005 (AI-230): Access Definition case
4373 else pragma Assert (Present (Access_Definition (Component_Def)));
4375 -- Indicate that the anonymous access type is created by the
4376 -- array type declaration.
4378 Element_Type := Access_Definition
4380 N => Access_Definition (Component_Def));
4381 Set_Is_Local_Anonymous_Access (Element_Type);
4383 -- Propagate the parent. This field is needed if we have to generate
4384 -- the master_id associated with an anonymous access to task type
4385 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
4387 Set_Parent (Element_Type, Parent (T));
4389 -- Ada 2005 (AI-230): In case of components that are anonymous access
4390 -- types the level of accessibility depends on the enclosing type
4393 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
4395 -- Ada 2005 (AI-254)
4398 CD : constant Node_Id :=
4399 Access_To_Subprogram_Definition
4400 (Access_Definition (Component_Def));
4402 if Present (CD) and then Protected_Present (CD) then
4404 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
4409 -- Constrained array case
4412 T := Create_Itype (E_Void, P, Related_Id, 'T');
4415 if Nkind (Def) = N_Constrained_Array_Definition then
4417 -- Establish Implicit_Base as unconstrained base type
4419 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
4421 Set_Etype (Implicit_Base, Implicit_Base);
4422 Set_Scope (Implicit_Base, Current_Scope);
4423 Set_Has_Delayed_Freeze (Implicit_Base);
4425 -- The constrained array type is a subtype of the unconstrained one
4427 Set_Ekind (T, E_Array_Subtype);
4428 Init_Size_Align (T);
4429 Set_Etype (T, Implicit_Base);
4430 Set_Scope (T, Current_Scope);
4431 Set_Is_Constrained (T, True);
4432 Set_First_Index (T, First (Discrete_Subtype_Definitions (Def)));
4433 Set_Has_Delayed_Freeze (T);
4435 -- Complete setup of implicit base type
4437 Set_First_Index (Implicit_Base, First_Index (T));
4438 Set_Component_Type (Implicit_Base, Element_Type);
4439 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
4440 Set_Component_Size (Implicit_Base, Uint_0);
4441 Set_Packed_Array_Type (Implicit_Base, Empty);
4442 Set_Has_Controlled_Component
4443 (Implicit_Base, Has_Controlled_Component
4445 or else Is_Controlled
4447 Set_Finalize_Storage_Only
4448 (Implicit_Base, Finalize_Storage_Only
4451 -- Unconstrained array case
4454 Set_Ekind (T, E_Array_Type);
4455 Init_Size_Align (T);
4457 Set_Scope (T, Current_Scope);
4458 Set_Component_Size (T, Uint_0);
4459 Set_Is_Constrained (T, False);
4460 Set_First_Index (T, First (Subtype_Marks (Def)));
4461 Set_Has_Delayed_Freeze (T, True);
4462 Set_Has_Task (T, Has_Task (Element_Type));
4463 Set_Has_Controlled_Component (T, Has_Controlled_Component
4466 Is_Controlled (Element_Type));
4467 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
4471 -- Common attributes for both cases
4473 Set_Component_Type (Base_Type (T), Element_Type);
4474 Set_Packed_Array_Type (T, Empty);
4476 if Aliased_Present (Component_Definition (Def)) then
4477 Set_Has_Aliased_Components (Etype (T));
4480 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
4481 -- array type to ensure that objects of this type are initialized.
4483 if Ada_Version >= Ada_05
4484 and then Can_Never_Be_Null (Element_Type)
4486 Set_Can_Never_Be_Null (T);
4488 if Null_Exclusion_Present (Component_Definition (Def))
4490 -- No need to check itypes because in their case this check was
4491 -- done at their point of creation
4493 and then not Is_Itype (Element_Type)
4496 ("`NOT NULL` not allowed (null already excluded)",
4497 Subtype_Indication (Component_Definition (Def)));
4501 Priv := Private_Component (Element_Type);
4503 if Present (Priv) then
4505 -- Check for circular definitions
4507 if Priv = Any_Type then
4508 Set_Component_Type (Etype (T), Any_Type);
4510 -- There is a gap in the visibility of operations on the composite
4511 -- type only if the component type is defined in a different scope.
4513 elsif Scope (Priv) = Current_Scope then
4516 elsif Is_Limited_Type (Priv) then
4517 Set_Is_Limited_Composite (Etype (T));
4518 Set_Is_Limited_Composite (T);
4520 Set_Is_Private_Composite (Etype (T));
4521 Set_Is_Private_Composite (T);
4525 -- A syntax error in the declaration itself may lead to an empty index
4526 -- list, in which case do a minimal patch.
4528 if No (First_Index (T)) then
4529 Error_Msg_N ("missing index definition in array type declaration", T);
4532 Indices : constant List_Id :=
4533 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
4535 Set_Discrete_Subtype_Definitions (Def, Indices);
4536 Set_First_Index (T, First (Indices));
4541 -- Create a concatenation operator for the new type. Internal array
4542 -- types created for packed entities do not need such, they are
4543 -- compatible with the user-defined type.
4545 if Number_Dimensions (T) = 1
4546 and then not Is_Packed_Array_Type (T)
4548 New_Concatenation_Op (T);
4551 -- In the case of an unconstrained array the parser has already verified
4552 -- that all the indices are unconstrained but we still need to make sure
4553 -- that the element type is constrained.
4555 if Is_Indefinite_Subtype (Element_Type) then
4557 ("unconstrained element type in array declaration",
4558 Subtype_Indication (Component_Def));
4560 elsif Is_Abstract_Type (Element_Type) then
4562 ("the type of a component cannot be abstract",
4563 Subtype_Indication (Component_Def));
4565 end Array_Type_Declaration;
4567 ------------------------------------------------------
4568 -- Replace_Anonymous_Access_To_Protected_Subprogram --
4569 ------------------------------------------------------
4571 function Replace_Anonymous_Access_To_Protected_Subprogram
4572 (N : Node_Id) return Entity_Id
4574 Loc : constant Source_Ptr := Sloc (N);
4576 Curr_Scope : constant Scope_Stack_Entry :=
4577 Scope_Stack.Table (Scope_Stack.Last);
4579 Anon : constant Entity_Id :=
4580 Make_Defining_Identifier (Loc,
4581 Chars => New_Internal_Name ('S'));
4589 Set_Is_Internal (Anon);
4592 when N_Component_Declaration |
4593 N_Unconstrained_Array_Definition |
4594 N_Constrained_Array_Definition =>
4595 Comp := Component_Definition (N);
4596 Acc := Access_Definition (Comp);
4598 when N_Discriminant_Specification =>
4599 Comp := Discriminant_Type (N);
4602 when N_Parameter_Specification =>
4603 Comp := Parameter_Type (N);
4606 when N_Access_Function_Definition =>
4607 Comp := Result_Definition (N);
4610 when N_Object_Declaration =>
4611 Comp := Object_Definition (N);
4614 when N_Function_Specification =>
4615 Comp := Result_Definition (N);
4619 raise Program_Error;
4622 Decl := Make_Full_Type_Declaration (Loc,
4623 Defining_Identifier => Anon,
4625 Copy_Separate_Tree (Access_To_Subprogram_Definition (Acc)));
4627 Mark_Rewrite_Insertion (Decl);
4629 -- Insert the new declaration in the nearest enclosing scope. If the
4630 -- node is a body and N is its return type, the declaration belongs in
4631 -- the enclosing scope.
4635 if Nkind (P) = N_Subprogram_Body
4636 and then Nkind (N) = N_Function_Specification
4641 while Present (P) and then not Has_Declarations (P) loop
4645 pragma Assert (Present (P));
4647 if Nkind (P) = N_Package_Specification then
4648 Prepend (Decl, Visible_Declarations (P));
4650 Prepend (Decl, Declarations (P));
4653 -- Replace the anonymous type with an occurrence of the new declaration.
4654 -- In all cases the rewritten node does not have the null-exclusion
4655 -- attribute because (if present) it was already inherited by the
4656 -- anonymous entity (Anon). Thus, in case of components we do not
4657 -- inherit this attribute.
4659 if Nkind (N) = N_Parameter_Specification then
4660 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
4661 Set_Etype (Defining_Identifier (N), Anon);
4662 Set_Null_Exclusion_Present (N, False);
4664 elsif Nkind (N) = N_Object_Declaration then
4665 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
4666 Set_Etype (Defining_Identifier (N), Anon);
4668 elsif Nkind (N) = N_Access_Function_Definition then
4669 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
4671 elsif Nkind (N) = N_Function_Specification then
4672 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
4673 Set_Etype (Defining_Unit_Name (N), Anon);
4677 Make_Component_Definition (Loc,
4678 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
4681 Mark_Rewrite_Insertion (Comp);
4683 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition) then
4687 -- Temporarily remove the current scope (record or subprogram) from
4688 -- the stack to add the new declarations to the enclosing scope.
4690 Scope_Stack.Decrement_Last;
4692 Set_Is_Itype (Anon);
4693 Scope_Stack.Append (Curr_Scope);
4696 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
4697 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
4699 end Replace_Anonymous_Access_To_Protected_Subprogram;
4701 -------------------------------
4702 -- Build_Derived_Access_Type --
4703 -------------------------------
4705 procedure Build_Derived_Access_Type
4707 Parent_Type : Entity_Id;
4708 Derived_Type : Entity_Id)
4710 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
4712 Desig_Type : Entity_Id;
4714 Discr_Con_Elist : Elist_Id;
4715 Discr_Con_El : Elmt_Id;
4719 -- Set the designated type so it is available in case this is an access
4720 -- to a self-referential type, e.g. a standard list type with a next
4721 -- pointer. Will be reset after subtype is built.
4723 Set_Directly_Designated_Type
4724 (Derived_Type, Designated_Type (Parent_Type));
4726 Subt := Process_Subtype (S, N);
4728 if Nkind (S) /= N_Subtype_Indication
4729 and then Subt /= Base_Type (Subt)
4731 Set_Ekind (Derived_Type, E_Access_Subtype);
4734 if Ekind (Derived_Type) = E_Access_Subtype then
4736 Pbase : constant Entity_Id := Base_Type (Parent_Type);
4737 Ibase : constant Entity_Id :=
4738 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
4739 Svg_Chars : constant Name_Id := Chars (Ibase);
4740 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
4743 Copy_Node (Pbase, Ibase);
4745 Set_Chars (Ibase, Svg_Chars);
4746 Set_Next_Entity (Ibase, Svg_Next_E);
4747 Set_Sloc (Ibase, Sloc (Derived_Type));
4748 Set_Scope (Ibase, Scope (Derived_Type));
4749 Set_Freeze_Node (Ibase, Empty);
4750 Set_Is_Frozen (Ibase, False);
4751 Set_Comes_From_Source (Ibase, False);
4752 Set_Is_First_Subtype (Ibase, False);
4754 Set_Etype (Ibase, Pbase);
4755 Set_Etype (Derived_Type, Ibase);
4759 Set_Directly_Designated_Type
4760 (Derived_Type, Designated_Type (Subt));
4762 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
4763 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
4764 Set_Size_Info (Derived_Type, Parent_Type);
4765 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
4766 Set_Depends_On_Private (Derived_Type,
4767 Has_Private_Component (Derived_Type));
4768 Conditional_Delay (Derived_Type, Subt);
4770 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
4771 -- that it is not redundant.
4773 if Null_Exclusion_Present (Type_Definition (N)) then
4774 Set_Can_Never_Be_Null (Derived_Type);
4776 if Can_Never_Be_Null (Parent_Type)
4780 ("`NOT NULL` not allowed (& already excludes null)",
4784 elsif Can_Never_Be_Null (Parent_Type) then
4785 Set_Can_Never_Be_Null (Derived_Type);
4788 -- Note: we do not copy the Storage_Size_Variable, since we always go to
4789 -- the root type for this information.
4791 -- Apply range checks to discriminants for derived record case
4792 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
4794 Desig_Type := Designated_Type (Derived_Type);
4795 if Is_Composite_Type (Desig_Type)
4796 and then (not Is_Array_Type (Desig_Type))
4797 and then Has_Discriminants (Desig_Type)
4798 and then Base_Type (Desig_Type) /= Desig_Type
4800 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
4801 Discr_Con_El := First_Elmt (Discr_Con_Elist);
4803 Discr := First_Discriminant (Base_Type (Desig_Type));
4804 while Present (Discr_Con_El) loop
4805 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
4806 Next_Elmt (Discr_Con_El);
4807 Next_Discriminant (Discr);
4810 end Build_Derived_Access_Type;
4812 ------------------------------
4813 -- Build_Derived_Array_Type --
4814 ------------------------------
4816 procedure Build_Derived_Array_Type
4818 Parent_Type : Entity_Id;
4819 Derived_Type : Entity_Id)
4821 Loc : constant Source_Ptr := Sloc (N);
4822 Tdef : constant Node_Id := Type_Definition (N);
4823 Indic : constant Node_Id := Subtype_Indication (Tdef);
4824 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
4825 Implicit_Base : Entity_Id;
4826 New_Indic : Node_Id;
4828 procedure Make_Implicit_Base;
4829 -- If the parent subtype is constrained, the derived type is a subtype
4830 -- of an implicit base type derived from the parent base.
4832 ------------------------
4833 -- Make_Implicit_Base --
4834 ------------------------
4836 procedure Make_Implicit_Base is
4839 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
4841 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
4842 Set_Etype (Implicit_Base, Parent_Base);
4844 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
4845 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
4847 Set_Has_Delayed_Freeze (Implicit_Base, True);
4848 end Make_Implicit_Base;
4850 -- Start of processing for Build_Derived_Array_Type
4853 if not Is_Constrained (Parent_Type) then
4854 if Nkind (Indic) /= N_Subtype_Indication then
4855 Set_Ekind (Derived_Type, E_Array_Type);
4857 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
4858 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
4860 Set_Has_Delayed_Freeze (Derived_Type, True);
4864 Set_Etype (Derived_Type, Implicit_Base);
4867 Make_Subtype_Declaration (Loc,
4868 Defining_Identifier => Derived_Type,
4869 Subtype_Indication =>
4870 Make_Subtype_Indication (Loc,
4871 Subtype_Mark => New_Reference_To (Implicit_Base, Loc),
4872 Constraint => Constraint (Indic)));
4874 Rewrite (N, New_Indic);
4879 if Nkind (Indic) /= N_Subtype_Indication then
4882 Set_Ekind (Derived_Type, Ekind (Parent_Type));
4883 Set_Etype (Derived_Type, Implicit_Base);
4884 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
4887 Error_Msg_N ("illegal constraint on constrained type", Indic);
4891 -- If parent type is not a derived type itself, and is declared in
4892 -- closed scope (e.g. a subprogram), then we must explicitly introduce
4893 -- the new type's concatenation operator since Derive_Subprograms
4894 -- will not inherit the parent's operator. If the parent type is
4895 -- unconstrained, the operator is of the unconstrained base type.
4897 if Number_Dimensions (Parent_Type) = 1
4898 and then not Is_Limited_Type (Parent_Type)
4899 and then not Is_Derived_Type (Parent_Type)
4900 and then not Is_Package_Or_Generic_Package
4901 (Scope (Base_Type (Parent_Type)))
4903 if not Is_Constrained (Parent_Type)
4904 and then Is_Constrained (Derived_Type)
4906 New_Concatenation_Op (Implicit_Base);
4908 New_Concatenation_Op (Derived_Type);
4911 end Build_Derived_Array_Type;
4913 -----------------------------------
4914 -- Build_Derived_Concurrent_Type --
4915 -----------------------------------
4917 procedure Build_Derived_Concurrent_Type
4919 Parent_Type : Entity_Id;
4920 Derived_Type : Entity_Id)
4922 Loc : constant Source_Ptr := Sloc (N);
4924 Corr_Record : constant Entity_Id :=
4925 Make_Defining_Identifier (Loc, New_Internal_Name ('C'));
4927 Corr_Decl : Node_Id;
4928 Corr_Decl_Needed : Boolean;
4929 -- If the derived type has fewer discriminants than its parent, the
4930 -- corresponding record is also a derived type, in order to account for
4931 -- the bound discriminants. We create a full type declaration for it in
4934 Constraint_Present : constant Boolean :=
4935 Nkind (Subtype_Indication (Type_Definition (N))) =
4936 N_Subtype_Indication;
4938 D_Constraint : Node_Id;
4939 New_Constraint : Elist_Id;
4940 Old_Disc : Entity_Id;
4941 New_Disc : Entity_Id;
4945 Set_Stored_Constraint (Derived_Type, No_Elist);
4946 Corr_Decl_Needed := False;
4949 if Present (Discriminant_Specifications (N))
4950 and then Constraint_Present
4952 Old_Disc := First_Discriminant (Parent_Type);
4953 New_Disc := First (Discriminant_Specifications (N));
4954 while Present (New_Disc) and then Present (Old_Disc) loop
4955 Next_Discriminant (Old_Disc);
4960 if Present (Old_Disc) then
4962 -- The new type has fewer discriminants, so we need to create a new
4963 -- corresponding record, which is derived from the corresponding
4964 -- record of the parent, and has a stored constraint that captures
4965 -- the values of the discriminant constraints.
4967 -- The type declaration for the derived corresponding record has
4968 -- the same discriminant part and constraints as the current
4969 -- declaration. Copy the unanalyzed tree to build declaration.
4971 Corr_Decl_Needed := True;
4972 New_N := Copy_Separate_Tree (N);
4975 Make_Full_Type_Declaration (Loc,
4976 Defining_Identifier => Corr_Record,
4977 Discriminant_Specifications =>
4978 Discriminant_Specifications (New_N),
4980 Make_Derived_Type_Definition (Loc,
4981 Subtype_Indication =>
4982 Make_Subtype_Indication (Loc,
4985 (Corresponding_Record_Type (Parent_Type), Loc),
4988 (Subtype_Indication (Type_Definition (New_N))))));
4991 -- Copy Storage_Size and Relative_Deadline variables if task case
4993 if Is_Task_Type (Parent_Type) then
4994 Set_Storage_Size_Variable (Derived_Type,
4995 Storage_Size_Variable (Parent_Type));
4996 Set_Relative_Deadline_Variable (Derived_Type,
4997 Relative_Deadline_Variable (Parent_Type));
5000 if Present (Discriminant_Specifications (N)) then
5001 Push_Scope (Derived_Type);
5002 Check_Or_Process_Discriminants (N, Derived_Type);
5004 if Constraint_Present then
5006 Expand_To_Stored_Constraint
5008 Build_Discriminant_Constraints
5010 Subtype_Indication (Type_Definition (N)), True));
5015 elsif Constraint_Present then
5017 -- Build constrained subtype and derive from it
5020 Loc : constant Source_Ptr := Sloc (N);
5021 Anon : constant Entity_Id :=
5022 Make_Defining_Identifier (Loc,
5023 New_External_Name (Chars (Derived_Type), 'T'));
5028 Make_Subtype_Declaration (Loc,
5029 Defining_Identifier => Anon,
5030 Subtype_Indication =>
5031 Subtype_Indication (Type_Definition (N)));
5032 Insert_Before (N, Decl);
5035 Rewrite (Subtype_Indication (Type_Definition (N)),
5036 New_Occurrence_Of (Anon, Loc));
5037 Set_Analyzed (Derived_Type, False);
5043 -- By default, operations and private data are inherited from parent.
5044 -- However, in the presence of bound discriminants, a new corresponding
5045 -- record will be created, see below.
5047 Set_Has_Discriminants
5048 (Derived_Type, Has_Discriminants (Parent_Type));
5049 Set_Corresponding_Record_Type
5050 (Derived_Type, Corresponding_Record_Type (Parent_Type));
5052 -- Is_Constrained is set according the parent subtype, but is set to
5053 -- False if the derived type is declared with new discriminants.
5057 (Is_Constrained (Parent_Type) or else Constraint_Present)
5058 and then not Present (Discriminant_Specifications (N)));
5060 if Constraint_Present then
5061 if not Has_Discriminants (Parent_Type) then
5062 Error_Msg_N ("untagged parent must have discriminants", N);
5064 elsif Present (Discriminant_Specifications (N)) then
5066 -- Verify that new discriminants are used to constrain old ones
5071 (Constraint (Subtype_Indication (Type_Definition (N)))));
5073 Old_Disc := First_Discriminant (Parent_Type);
5075 while Present (D_Constraint) loop
5076 if Nkind (D_Constraint) /= N_Discriminant_Association then
5078 -- Positional constraint. If it is a reference to a new
5079 -- discriminant, it constrains the corresponding old one.
5081 if Nkind (D_Constraint) = N_Identifier then
5082 New_Disc := First_Discriminant (Derived_Type);
5083 while Present (New_Disc) loop
5084 exit when Chars (New_Disc) = Chars (D_Constraint);
5085 Next_Discriminant (New_Disc);
5088 if Present (New_Disc) then
5089 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
5093 Next_Discriminant (Old_Disc);
5095 -- if this is a named constraint, search by name for the old
5096 -- discriminants constrained by the new one.
5098 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
5100 -- Find new discriminant with that name
5102 New_Disc := First_Discriminant (Derived_Type);
5103 while Present (New_Disc) loop
5105 Chars (New_Disc) = Chars (Expression (D_Constraint));
5106 Next_Discriminant (New_Disc);
5109 if Present (New_Disc) then
5111 -- Verify that new discriminant renames some discriminant
5112 -- of the parent type, and associate the new discriminant
5113 -- with one or more old ones that it renames.
5119 Selector := First (Selector_Names (D_Constraint));
5120 while Present (Selector) loop
5121 Old_Disc := First_Discriminant (Parent_Type);
5122 while Present (Old_Disc) loop
5123 exit when Chars (Old_Disc) = Chars (Selector);
5124 Next_Discriminant (Old_Disc);
5127 if Present (Old_Disc) then
5128 Set_Corresponding_Discriminant
5129 (New_Disc, Old_Disc);
5138 Next (D_Constraint);
5141 New_Disc := First_Discriminant (Derived_Type);
5142 while Present (New_Disc) loop
5143 if No (Corresponding_Discriminant (New_Disc)) then
5145 ("new discriminant& must constrain old one", N, New_Disc);
5148 Subtypes_Statically_Compatible
5150 Etype (Corresponding_Discriminant (New_Disc)))
5153 ("& not statically compatible with parent discriminant",
5157 Next_Discriminant (New_Disc);
5161 elsif Present (Discriminant_Specifications (N)) then
5163 ("missing discriminant constraint in untagged derivation", N);
5166 -- The entity chain of the derived type includes the new discriminants
5167 -- but shares operations with the parent.
5169 if Present (Discriminant_Specifications (N)) then
5170 Old_Disc := First_Discriminant (Parent_Type);
5171 while Present (Old_Disc) loop
5172 if No (Next_Entity (Old_Disc))
5173 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
5176 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
5180 Next_Discriminant (Old_Disc);
5184 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
5185 if Has_Discriminants (Parent_Type) then
5186 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5187 Set_Discriminant_Constraint (
5188 Derived_Type, Discriminant_Constraint (Parent_Type));
5192 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
5194 Set_Has_Completion (Derived_Type);
5196 if Corr_Decl_Needed then
5197 Set_Stored_Constraint (Derived_Type, New_Constraint);
5198 Insert_After (N, Corr_Decl);
5199 Analyze (Corr_Decl);
5200 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
5202 end Build_Derived_Concurrent_Type;
5204 ------------------------------------
5205 -- Build_Derived_Enumeration_Type --
5206 ------------------------------------
5208 procedure Build_Derived_Enumeration_Type
5210 Parent_Type : Entity_Id;
5211 Derived_Type : Entity_Id)
5213 Loc : constant Source_Ptr := Sloc (N);
5214 Def : constant Node_Id := Type_Definition (N);
5215 Indic : constant Node_Id := Subtype_Indication (Def);
5216 Implicit_Base : Entity_Id;
5217 Literal : Entity_Id;
5218 New_Lit : Entity_Id;
5219 Literals_List : List_Id;
5220 Type_Decl : Node_Id;
5222 Rang_Expr : Node_Id;
5225 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
5226 -- not have explicit literals lists we need to process types derived
5227 -- from them specially. This is handled by Derived_Standard_Character.
5228 -- If the parent type is a generic type, there are no literals either,
5229 -- and we construct the same skeletal representation as for the generic
5232 if Is_Standard_Character_Type (Parent_Type) then
5233 Derived_Standard_Character (N, Parent_Type, Derived_Type);
5235 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
5241 if Nkind (Indic) /= N_Subtype_Indication then
5243 Make_Attribute_Reference (Loc,
5244 Attribute_Name => Name_First,
5245 Prefix => New_Reference_To (Derived_Type, Loc));
5246 Set_Etype (Lo, Derived_Type);
5249 Make_Attribute_Reference (Loc,
5250 Attribute_Name => Name_Last,
5251 Prefix => New_Reference_To (Derived_Type, Loc));
5252 Set_Etype (Hi, Derived_Type);
5254 Set_Scalar_Range (Derived_Type,
5260 -- Analyze subtype indication and verify compatibility
5261 -- with parent type.
5263 if Base_Type (Process_Subtype (Indic, N)) /=
5264 Base_Type (Parent_Type)
5267 ("illegal constraint for formal discrete type", N);
5273 -- If a constraint is present, analyze the bounds to catch
5274 -- premature usage of the derived literals.
5276 if Nkind (Indic) = N_Subtype_Indication
5277 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
5279 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
5280 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
5283 -- Introduce an implicit base type for the derived type even if there
5284 -- is no constraint attached to it, since this seems closer to the
5285 -- Ada semantics. Build a full type declaration tree for the derived
5286 -- type using the implicit base type as the defining identifier. The
5287 -- build a subtype declaration tree which applies the constraint (if
5288 -- any) have it replace the derived type declaration.
5290 Literal := First_Literal (Parent_Type);
5291 Literals_List := New_List;
5292 while Present (Literal)
5293 and then Ekind (Literal) = E_Enumeration_Literal
5295 -- Literals of the derived type have the same representation as
5296 -- those of the parent type, but this representation can be
5297 -- overridden by an explicit representation clause. Indicate
5298 -- that there is no explicit representation given yet. These
5299 -- derived literals are implicit operations of the new type,
5300 -- and can be overridden by explicit ones.
5302 if Nkind (Literal) = N_Defining_Character_Literal then
5304 Make_Defining_Character_Literal (Loc, Chars (Literal));
5306 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
5309 Set_Ekind (New_Lit, E_Enumeration_Literal);
5310 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
5311 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
5312 Set_Enumeration_Rep_Expr (New_Lit, Empty);
5313 Set_Alias (New_Lit, Literal);
5314 Set_Is_Known_Valid (New_Lit, True);
5316 Append (New_Lit, Literals_List);
5317 Next_Literal (Literal);
5321 Make_Defining_Identifier (Sloc (Derived_Type),
5322 New_External_Name (Chars (Derived_Type), 'B'));
5324 -- Indicate the proper nature of the derived type. This must be done
5325 -- before analysis of the literals, to recognize cases when a literal
5326 -- may be hidden by a previous explicit function definition (cf.
5329 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
5330 Set_Etype (Derived_Type, Implicit_Base);
5333 Make_Full_Type_Declaration (Loc,
5334 Defining_Identifier => Implicit_Base,
5335 Discriminant_Specifications => No_List,
5337 Make_Enumeration_Type_Definition (Loc, Literals_List));
5339 Mark_Rewrite_Insertion (Type_Decl);
5340 Insert_Before (N, Type_Decl);
5341 Analyze (Type_Decl);
5343 -- After the implicit base is analyzed its Etype needs to be changed
5344 -- to reflect the fact that it is derived from the parent type which
5345 -- was ignored during analysis. We also set the size at this point.
5347 Set_Etype (Implicit_Base, Parent_Type);
5349 Set_Size_Info (Implicit_Base, Parent_Type);
5350 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
5351 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
5353 Set_Has_Non_Standard_Rep
5354 (Implicit_Base, Has_Non_Standard_Rep
5356 Set_Has_Delayed_Freeze (Implicit_Base);
5358 -- Process the subtype indication including a validation check on the
5359 -- constraint, if any. If a constraint is given, its bounds must be
5360 -- implicitly converted to the new type.
5362 if Nkind (Indic) = N_Subtype_Indication then
5364 R : constant Node_Id :=
5365 Range_Expression (Constraint (Indic));
5368 if Nkind (R) = N_Range then
5369 Hi := Build_Scalar_Bound
5370 (High_Bound (R), Parent_Type, Implicit_Base);
5371 Lo := Build_Scalar_Bound
5372 (Low_Bound (R), Parent_Type, Implicit_Base);
5375 -- Constraint is a Range attribute. Replace with explicit
5376 -- mention of the bounds of the prefix, which must be a
5379 Analyze (Prefix (R));
5381 Convert_To (Implicit_Base,
5382 Make_Attribute_Reference (Loc,
5383 Attribute_Name => Name_Last,
5385 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
5388 Convert_To (Implicit_Base,
5389 Make_Attribute_Reference (Loc,
5390 Attribute_Name => Name_First,
5392 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
5399 (Type_High_Bound (Parent_Type),
5400 Parent_Type, Implicit_Base);
5403 (Type_Low_Bound (Parent_Type),
5404 Parent_Type, Implicit_Base);
5412 -- If we constructed a default range for the case where no range
5413 -- was given, then the expressions in the range must not freeze
5414 -- since they do not correspond to expressions in the source.
5416 if Nkind (Indic) /= N_Subtype_Indication then
5417 Set_Must_Not_Freeze (Lo);
5418 Set_Must_Not_Freeze (Hi);
5419 Set_Must_Not_Freeze (Rang_Expr);
5423 Make_Subtype_Declaration (Loc,
5424 Defining_Identifier => Derived_Type,
5425 Subtype_Indication =>
5426 Make_Subtype_Indication (Loc,
5427 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
5429 Make_Range_Constraint (Loc,
5430 Range_Expression => Rang_Expr))));
5434 -- If pragma Discard_Names applies on the first subtype of the parent
5435 -- type, then it must be applied on this subtype as well.
5437 if Einfo.Discard_Names (First_Subtype (Parent_Type)) then
5438 Set_Discard_Names (Derived_Type);
5441 -- Apply a range check. Since this range expression doesn't have an
5442 -- Etype, we have to specifically pass the Source_Typ parameter. Is
5445 if Nkind (Indic) = N_Subtype_Indication then
5446 Apply_Range_Check (Range_Expression (Constraint (Indic)),
5448 Source_Typ => Entity (Subtype_Mark (Indic)));
5451 end Build_Derived_Enumeration_Type;
5453 --------------------------------
5454 -- Build_Derived_Numeric_Type --
5455 --------------------------------
5457 procedure Build_Derived_Numeric_Type
5459 Parent_Type : Entity_Id;
5460 Derived_Type : Entity_Id)
5462 Loc : constant Source_Ptr := Sloc (N);
5463 Tdef : constant Node_Id := Type_Definition (N);
5464 Indic : constant Node_Id := Subtype_Indication (Tdef);
5465 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5466 No_Constraint : constant Boolean := Nkind (Indic) /=
5467 N_Subtype_Indication;
5468 Implicit_Base : Entity_Id;
5474 -- Process the subtype indication including a validation check on
5475 -- the constraint if any.
5477 Discard_Node (Process_Subtype (Indic, N));
5479 -- Introduce an implicit base type for the derived type even if there
5480 -- is no constraint attached to it, since this seems closer to the Ada
5484 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5486 Set_Etype (Implicit_Base, Parent_Base);
5487 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5488 Set_Size_Info (Implicit_Base, Parent_Base);
5489 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
5490 Set_Parent (Implicit_Base, Parent (Derived_Type));
5491 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
5493 -- Set RM Size for discrete type or decimal fixed-point type
5494 -- Ordinary fixed-point is excluded, why???
5496 if Is_Discrete_Type (Parent_Base)
5497 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
5499 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
5502 Set_Has_Delayed_Freeze (Implicit_Base);
5504 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
5505 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
5507 Set_Scalar_Range (Implicit_Base,
5512 if Has_Infinities (Parent_Base) then
5513 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
5516 -- The Derived_Type, which is the entity of the declaration, is a
5517 -- subtype of the implicit base. Its Ekind is a subtype, even in the
5518 -- absence of an explicit constraint.
5520 Set_Etype (Derived_Type, Implicit_Base);
5522 -- If we did not have a constraint, then the Ekind is set from the
5523 -- parent type (otherwise Process_Subtype has set the bounds)
5525 if No_Constraint then
5526 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
5529 -- If we did not have a range constraint, then set the range from the
5530 -- parent type. Otherwise, the call to Process_Subtype has set the
5534 or else not Has_Range_Constraint (Indic)
5536 Set_Scalar_Range (Derived_Type,
5538 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
5539 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
5540 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5542 if Has_Infinities (Parent_Type) then
5543 Set_Includes_Infinities (Scalar_Range (Derived_Type));
5546 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
5549 Set_Is_Descendent_Of_Address (Derived_Type,
5550 Is_Descendent_Of_Address (Parent_Type));
5551 Set_Is_Descendent_Of_Address (Implicit_Base,
5552 Is_Descendent_Of_Address (Parent_Type));
5554 -- Set remaining type-specific fields, depending on numeric type
5556 if Is_Modular_Integer_Type (Parent_Type) then
5557 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
5559 Set_Non_Binary_Modulus
5560 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
5563 (Implicit_Base, Is_Known_Valid (Parent_Base));
5565 elsif Is_Floating_Point_Type (Parent_Type) then
5567 -- Digits of base type is always copied from the digits value of
5568 -- the parent base type, but the digits of the derived type will
5569 -- already have been set if there was a constraint present.
5571 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
5572 Set_Vax_Float (Implicit_Base, Vax_Float (Parent_Base));
5574 if No_Constraint then
5575 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
5578 elsif Is_Fixed_Point_Type (Parent_Type) then
5580 -- Small of base type and derived type are always copied from the
5581 -- parent base type, since smalls never change. The delta of the
5582 -- base type is also copied from the parent base type. However the
5583 -- delta of the derived type will have been set already if a
5584 -- constraint was present.
5586 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
5587 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
5588 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
5590 if No_Constraint then
5591 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
5594 -- The scale and machine radix in the decimal case are always
5595 -- copied from the parent base type.
5597 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
5598 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
5599 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
5601 Set_Machine_Radix_10
5602 (Derived_Type, Machine_Radix_10 (Parent_Base));
5603 Set_Machine_Radix_10
5604 (Implicit_Base, Machine_Radix_10 (Parent_Base));
5606 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
5608 if No_Constraint then
5609 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
5612 -- the analysis of the subtype_indication sets the
5613 -- digits value of the derived type.
5620 -- The type of the bounds is that of the parent type, and they
5621 -- must be converted to the derived type.
5623 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
5625 -- The implicit_base should be frozen when the derived type is frozen,
5626 -- but note that it is used in the conversions of the bounds. For fixed
5627 -- types we delay the determination of the bounds until the proper
5628 -- freezing point. For other numeric types this is rejected by GCC, for
5629 -- reasons that are currently unclear (???), so we choose to freeze the
5630 -- implicit base now. In the case of integers and floating point types
5631 -- this is harmless because subsequent representation clauses cannot
5632 -- affect anything, but it is still baffling that we cannot use the
5633 -- same mechanism for all derived numeric types.
5635 -- There is a further complication: actually *some* representation
5636 -- clauses can affect the implicit base type. Namely, attribute
5637 -- definition clauses for stream-oriented attributes need to set the
5638 -- corresponding TSS entries on the base type, and this normally cannot
5639 -- be done after the base type is frozen, so the circuitry in
5640 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility and
5641 -- not use Set_TSS in this case.
5643 if Is_Fixed_Point_Type (Parent_Type) then
5644 Conditional_Delay (Implicit_Base, Parent_Type);
5646 Freeze_Before (N, Implicit_Base);
5648 end Build_Derived_Numeric_Type;
5650 --------------------------------
5651 -- Build_Derived_Private_Type --
5652 --------------------------------
5654 procedure Build_Derived_Private_Type
5656 Parent_Type : Entity_Id;
5657 Derived_Type : Entity_Id;
5658 Is_Completion : Boolean;
5659 Derive_Subps : Boolean := True)
5661 Loc : constant Source_Ptr := Sloc (N);
5662 Der_Base : Entity_Id;
5664 Full_Decl : Node_Id := Empty;
5665 Full_Der : Entity_Id;
5667 Last_Discr : Entity_Id;
5668 Par_Scope : constant Entity_Id := Scope (Base_Type (Parent_Type));
5669 Swapped : Boolean := False;
5671 procedure Copy_And_Build;
5672 -- Copy derived type declaration, replace parent with its full view,
5673 -- and analyze new declaration.
5675 --------------------
5676 -- Copy_And_Build --
5677 --------------------
5679 procedure Copy_And_Build is
5683 if Ekind (Parent_Type) in Record_Kind
5685 (Ekind (Parent_Type) in Enumeration_Kind
5686 and then not Is_Standard_Character_Type (Parent_Type)
5687 and then not Is_Generic_Type (Root_Type (Parent_Type)))
5689 Full_N := New_Copy_Tree (N);
5690 Insert_After (N, Full_N);
5691 Build_Derived_Type (
5692 Full_N, Parent_Type, Full_Der, True, Derive_Subps => False);
5695 Build_Derived_Type (
5696 N, Parent_Type, Full_Der, True, Derive_Subps => False);
5700 -- Start of processing for Build_Derived_Private_Type
5703 if Is_Tagged_Type (Parent_Type) then
5704 Full_P := Full_View (Parent_Type);
5706 -- A type extension of a type with unknown discriminants is an
5707 -- indefinite type that the back-end cannot handle directly.
5708 -- We treat it as a private type, and build a completion that is
5709 -- derived from the full view of the parent, and hopefully has
5710 -- known discriminants.
5712 -- If the full view of the parent type has an underlying record view,
5713 -- use it to generate the underlying record view of this derived type
5714 -- (required for chains of derivations with unknown discriminants).
5716 -- Minor optimization: we avoid the generation of useless underlying
5717 -- record view entities if the private type declaration has unknown
5718 -- discriminants but its corresponding full view has no
5721 if Has_Unknown_Discriminants (Parent_Type)
5722 and then Present (Full_P)
5723 and then (Has_Discriminants (Full_P)
5724 or else Present (Underlying_Record_View (Full_P)))
5725 and then not In_Open_Scopes (Par_Scope)
5726 and then Expander_Active
5729 Full_Der : constant Entity_Id :=
5730 Make_Defining_Identifier (Loc,
5731 Chars => New_Internal_Name ('T'));
5732 New_Ext : constant Node_Id :=
5734 (Record_Extension_Part (Type_Definition (N)));
5738 Build_Derived_Record_Type
5739 (N, Parent_Type, Derived_Type, Derive_Subps);
5741 -- Build anonymous completion, as a derivation from the full
5742 -- view of the parent. This is not a completion in the usual
5743 -- sense, because the current type is not private.
5746 Make_Full_Type_Declaration (Loc,
5747 Defining_Identifier => Full_Der,
5749 Make_Derived_Type_Definition (Loc,
5750 Subtype_Indication =>
5752 (Subtype_Indication (Type_Definition (N))),
5753 Record_Extension_Part => New_Ext));
5755 -- If the parent type has an underlying record view, use it
5756 -- here to build the new underlying record view.
5758 if Present (Underlying_Record_View (Full_P)) then
5760 (Nkind (Subtype_Indication (Type_Definition (Decl)))
5762 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
5763 Underlying_Record_View (Full_P));
5766 Install_Private_Declarations (Par_Scope);
5767 Install_Visible_Declarations (Par_Scope);
5768 Insert_Before (N, Decl);
5770 -- Mark entity as an underlying record view before analysis,
5771 -- to avoid generating the list of its primitive operations
5772 -- (which is not really required for this entity) and thus
5773 -- prevent spurious errors associated with missing overriding
5774 -- of abstract primitives (overridden only for Derived_Type).
5776 Set_Ekind (Full_Der, E_Record_Type);
5777 Set_Is_Underlying_Record_View (Full_Der);
5781 pragma Assert (Has_Discriminants (Full_Der)
5782 and then not Has_Unknown_Discriminants (Full_Der));
5784 Uninstall_Declarations (Par_Scope);
5786 -- Freeze the underlying record view, to prevent generation of
5787 -- useless dispatching information, which is simply shared with
5788 -- the real derived type.
5790 Set_Is_Frozen (Full_Der);
5792 -- Set up links between real entity and underlying record view
5794 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
5795 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
5798 -- If discriminants are known, build derived record
5801 Build_Derived_Record_Type
5802 (N, Parent_Type, Derived_Type, Derive_Subps);
5807 elsif Has_Discriminants (Parent_Type) then
5808 if Present (Full_View (Parent_Type)) then
5809 if not Is_Completion then
5811 -- Copy declaration for subsequent analysis, to provide a
5812 -- completion for what is a private declaration. Indicate that
5813 -- the full type is internally generated.
5815 Full_Decl := New_Copy_Tree (N);
5816 Full_Der := New_Copy (Derived_Type);
5817 Set_Comes_From_Source (Full_Decl, False);
5818 Set_Comes_From_Source (Full_Der, False);
5820 Insert_After (N, Full_Decl);
5823 -- If this is a completion, the full view being built is itself
5824 -- private. We build a subtype of the parent with the same
5825 -- constraints as this full view, to convey to the back end the
5826 -- constrained components and the size of this subtype. If the
5827 -- parent is constrained, its full view can serve as the
5828 -- underlying full view of the derived type.
5830 if No (Discriminant_Specifications (N)) then
5831 if Nkind (Subtype_Indication (Type_Definition (N))) =
5832 N_Subtype_Indication
5834 Build_Underlying_Full_View (N, Derived_Type, Parent_Type);
5836 elsif Is_Constrained (Full_View (Parent_Type)) then
5837 Set_Underlying_Full_View
5838 (Derived_Type, Full_View (Parent_Type));
5842 -- If there are new discriminants, the parent subtype is
5843 -- constrained by them, but it is not clear how to build
5844 -- the Underlying_Full_View in this case???
5851 -- Build partial view of derived type from partial view of parent
5853 Build_Derived_Record_Type
5854 (N, Parent_Type, Derived_Type, Derive_Subps);
5856 if Present (Full_View (Parent_Type)) and then not Is_Completion then
5857 if not In_Open_Scopes (Par_Scope)
5858 or else not In_Same_Source_Unit (N, Parent_Type)
5860 -- Swap partial and full views temporarily
5862 Install_Private_Declarations (Par_Scope);
5863 Install_Visible_Declarations (Par_Scope);
5867 -- Build full view of derived type from full view of parent which
5868 -- is now installed. Subprograms have been derived on the partial
5869 -- view, the completion does not derive them anew.
5871 if not Is_Tagged_Type (Parent_Type) then
5873 -- If the parent is itself derived from another private type,
5874 -- installing the private declarations has not affected its
5875 -- privacy status, so use its own full view explicitly.
5877 if Is_Private_Type (Parent_Type) then
5878 Build_Derived_Record_Type
5879 (Full_Decl, Full_View (Parent_Type), Full_Der, False);
5881 Build_Derived_Record_Type
5882 (Full_Decl, Parent_Type, Full_Der, False);
5886 -- If full view of parent is tagged, the completion inherits
5887 -- the proper primitive operations.
5889 Set_Defining_Identifier (Full_Decl, Full_Der);
5890 Build_Derived_Record_Type
5891 (Full_Decl, Parent_Type, Full_Der, Derive_Subps);
5892 Set_Analyzed (Full_Decl);
5896 Uninstall_Declarations (Par_Scope);
5898 if In_Open_Scopes (Par_Scope) then
5899 Install_Visible_Declarations (Par_Scope);
5903 Der_Base := Base_Type (Derived_Type);
5904 Set_Full_View (Derived_Type, Full_Der);
5905 Set_Full_View (Der_Base, Base_Type (Full_Der));
5907 -- Copy the discriminant list from full view to the partial views
5908 -- (base type and its subtype). Gigi requires that the partial and
5909 -- full views have the same discriminants.
5911 -- Note that since the partial view is pointing to discriminants
5912 -- in the full view, their scope will be that of the full view.
5913 -- This might cause some front end problems and need adjustment???
5915 Discr := First_Discriminant (Base_Type (Full_Der));
5916 Set_First_Entity (Der_Base, Discr);
5919 Last_Discr := Discr;
5920 Next_Discriminant (Discr);
5921 exit when No (Discr);
5924 Set_Last_Entity (Der_Base, Last_Discr);
5926 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
5927 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
5928 Set_Stored_Constraint (Full_Der, Stored_Constraint (Derived_Type));
5931 -- If this is a completion, the derived type stays private and
5932 -- there is no need to create a further full view, except in the
5933 -- unusual case when the derivation is nested within a child unit,
5939 elsif Present (Full_View (Parent_Type))
5940 and then Has_Discriminants (Full_View (Parent_Type))
5942 if Has_Unknown_Discriminants (Parent_Type)
5943 and then Nkind (Subtype_Indication (Type_Definition (N))) =
5944 N_Subtype_Indication
5947 ("cannot constrain type with unknown discriminants",
5948 Subtype_Indication (Type_Definition (N)));
5952 -- If full view of parent is a record type, build full view as a
5953 -- derivation from the parent's full view. Partial view remains
5954 -- private. For code generation and linking, the full view must have
5955 -- the same public status as the partial one. This full view is only
5956 -- needed if the parent type is in an enclosing scope, so that the
5957 -- full view may actually become visible, e.g. in a child unit. This
5958 -- is both more efficient, and avoids order of freezing problems with
5959 -- the added entities.
5961 if not Is_Private_Type (Full_View (Parent_Type))
5962 and then (In_Open_Scopes (Scope (Parent_Type)))
5964 Full_Der := Make_Defining_Identifier (Sloc (Derived_Type),
5965 Chars (Derived_Type));
5966 Set_Is_Itype (Full_Der);
5967 Set_Has_Private_Declaration (Full_Der);
5968 Set_Has_Private_Declaration (Derived_Type);
5969 Set_Associated_Node_For_Itype (Full_Der, N);
5970 Set_Parent (Full_Der, Parent (Derived_Type));
5971 Set_Full_View (Derived_Type, Full_Der);
5972 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
5973 Full_P := Full_View (Parent_Type);
5974 Exchange_Declarations (Parent_Type);
5976 Exchange_Declarations (Full_P);
5979 Build_Derived_Record_Type
5980 (N, Full_View (Parent_Type), Derived_Type,
5981 Derive_Subps => False);
5984 -- In any case, the primitive operations are inherited from the
5985 -- parent type, not from the internal full view.
5987 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
5989 if Derive_Subps then
5990 Derive_Subprograms (Parent_Type, Derived_Type);
5994 -- Untagged type, No discriminants on either view
5996 if Nkind (Subtype_Indication (Type_Definition (N))) =
5997 N_Subtype_Indication
6000 ("illegal constraint on type without discriminants", N);
6003 if Present (Discriminant_Specifications (N))
6004 and then Present (Full_View (Parent_Type))
6005 and then not Is_Tagged_Type (Full_View (Parent_Type))
6007 Error_Msg_N ("cannot add discriminants to untagged type", N);
6010 Set_Stored_Constraint (Derived_Type, No_Elist);
6011 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6012 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
6013 Set_Has_Controlled_Component
6014 (Derived_Type, Has_Controlled_Component
6017 -- Direct controlled types do not inherit Finalize_Storage_Only flag
6019 if not Is_Controlled (Parent_Type) then
6020 Set_Finalize_Storage_Only
6021 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
6024 -- Construct the implicit full view by deriving from full view of the
6025 -- parent type. In order to get proper visibility, we install the
6026 -- parent scope and its declarations.
6028 -- ??? If the parent is untagged private and its completion is
6029 -- tagged, this mechanism will not work because we cannot derive from
6030 -- the tagged full view unless we have an extension.
6032 if Present (Full_View (Parent_Type))
6033 and then not Is_Tagged_Type (Full_View (Parent_Type))
6034 and then not Is_Completion
6037 Make_Defining_Identifier (Sloc (Derived_Type),
6038 Chars => Chars (Derived_Type));
6039 Set_Is_Itype (Full_Der);
6040 Set_Has_Private_Declaration (Full_Der);
6041 Set_Has_Private_Declaration (Derived_Type);
6042 Set_Associated_Node_For_Itype (Full_Der, N);
6043 Set_Parent (Full_Der, Parent (Derived_Type));
6044 Set_Full_View (Derived_Type, Full_Der);
6046 if not In_Open_Scopes (Par_Scope) then
6047 Install_Private_Declarations (Par_Scope);
6048 Install_Visible_Declarations (Par_Scope);
6050 Uninstall_Declarations (Par_Scope);
6052 -- If parent scope is open and in another unit, and parent has a
6053 -- completion, then the derivation is taking place in the visible
6054 -- part of a child unit. In that case retrieve the full view of
6055 -- the parent momentarily.
6057 elsif not In_Same_Source_Unit (N, Parent_Type) then
6058 Full_P := Full_View (Parent_Type);
6059 Exchange_Declarations (Parent_Type);
6061 Exchange_Declarations (Full_P);
6063 -- Otherwise it is a local derivation
6069 Set_Scope (Full_Der, Current_Scope);
6070 Set_Is_First_Subtype (Full_Der,
6071 Is_First_Subtype (Derived_Type));
6072 Set_Has_Size_Clause (Full_Der, False);
6073 Set_Has_Alignment_Clause (Full_Der, False);
6074 Set_Next_Entity (Full_Der, Empty);
6075 Set_Has_Delayed_Freeze (Full_Der);
6076 Set_Is_Frozen (Full_Der, False);
6077 Set_Freeze_Node (Full_Der, Empty);
6078 Set_Depends_On_Private (Full_Der,
6079 Has_Private_Component (Full_Der));
6080 Set_Public_Status (Full_Der);
6084 Set_Has_Unknown_Discriminants (Derived_Type,
6085 Has_Unknown_Discriminants (Parent_Type));
6087 if Is_Private_Type (Derived_Type) then
6088 Set_Private_Dependents (Derived_Type, New_Elmt_List);
6091 if Is_Private_Type (Parent_Type)
6092 and then Base_Type (Parent_Type) = Parent_Type
6093 and then In_Open_Scopes (Scope (Parent_Type))
6095 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
6097 if Is_Child_Unit (Scope (Current_Scope))
6098 and then Is_Completion
6099 and then In_Private_Part (Current_Scope)
6100 and then Scope (Parent_Type) /= Current_Scope
6102 -- This is the unusual case where a type completed by a private
6103 -- derivation occurs within a package nested in a child unit, and
6104 -- the parent is declared in an ancestor. In this case, the full
6105 -- view of the parent type will become visible in the body of
6106 -- the enclosing child, and only then will the current type be
6107 -- possibly non-private. We build a underlying full view that
6108 -- will be installed when the enclosing child body is compiled.
6111 Make_Defining_Identifier (Sloc (Derived_Type),
6112 Chars => Chars (Derived_Type));
6113 Set_Is_Itype (Full_Der);
6114 Build_Itype_Reference (Full_Der, N);
6116 -- The full view will be used to swap entities on entry/exit to
6117 -- the body, and must appear in the entity list for the package.
6119 Append_Entity (Full_Der, Scope (Derived_Type));
6120 Set_Has_Private_Declaration (Full_Der);
6121 Set_Has_Private_Declaration (Derived_Type);
6122 Set_Associated_Node_For_Itype (Full_Der, N);
6123 Set_Parent (Full_Der, Parent (Derived_Type));
6124 Full_P := Full_View (Parent_Type);
6125 Exchange_Declarations (Parent_Type);
6127 Exchange_Declarations (Full_P);
6128 Set_Underlying_Full_View (Derived_Type, Full_Der);
6131 end Build_Derived_Private_Type;
6133 -------------------------------
6134 -- Build_Derived_Record_Type --
6135 -------------------------------
6139 -- Ideally we would like to use the same model of type derivation for
6140 -- tagged and untagged record types. Unfortunately this is not quite
6141 -- possible because the semantics of representation clauses is different
6142 -- for tagged and untagged records under inheritance. Consider the
6145 -- type R (...) is [tagged] record ... end record;
6146 -- type T (...) is new R (...) [with ...];
6148 -- The representation clauses for T can specify a completely different
6149 -- record layout from R's. Hence the same component can be placed in two
6150 -- very different positions in objects of type T and R. If R and T are
6151 -- tagged types, representation clauses for T can only specify the layout
6152 -- of non inherited components, thus components that are common in R and T
6153 -- have the same position in objects of type R and T.
6155 -- This has two implications. The first is that the entire tree for R's
6156 -- declaration needs to be copied for T in the untagged case, so that T
6157 -- can be viewed as a record type of its own with its own representation
6158 -- clauses. The second implication is the way we handle discriminants.
6159 -- Specifically, in the untagged case we need a way to communicate to Gigi
6160 -- what are the real discriminants in the record, while for the semantics
6161 -- we need to consider those introduced by the user to rename the
6162 -- discriminants in the parent type. This is handled by introducing the
6163 -- notion of stored discriminants. See below for more.
6165 -- Fortunately the way regular components are inherited can be handled in
6166 -- the same way in tagged and untagged types.
6168 -- To complicate things a bit more the private view of a private extension
6169 -- cannot be handled in the same way as the full view (for one thing the
6170 -- semantic rules are somewhat different). We will explain what differs
6173 -- 2. DISCRIMINANTS UNDER INHERITANCE
6175 -- The semantic rules governing the discriminants of derived types are
6178 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
6179 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
6181 -- If parent type has discriminants, then the discriminants that are
6182 -- declared in the derived type are [3.4 (11)]:
6184 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
6187 -- o Otherwise, each discriminant of the parent type (implicitly declared
6188 -- in the same order with the same specifications). In this case, the
6189 -- discriminants are said to be "inherited", or if unknown in the parent
6190 -- are also unknown in the derived type.
6192 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
6194 -- o The parent subtype shall be constrained;
6196 -- o If the parent type is not a tagged type, then each discriminant of
6197 -- the derived type shall be used in the constraint defining a parent
6198 -- subtype. [Implementation note: This ensures that the new discriminant
6199 -- can share storage with an existing discriminant.]
6201 -- For the derived type each discriminant of the parent type is either
6202 -- inherited, constrained to equal some new discriminant of the derived
6203 -- type, or constrained to the value of an expression.
6205 -- When inherited or constrained to equal some new discriminant, the
6206 -- parent discriminant and the discriminant of the derived type are said
6209 -- If a discriminant of the parent type is constrained to a specific value
6210 -- in the derived type definition, then the discriminant is said to be
6211 -- "specified" by that derived type definition.
6213 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
6215 -- We have spoken about stored discriminants in point 1 (introduction)
6216 -- above. There are two sort of stored discriminants: implicit and
6217 -- explicit. As long as the derived type inherits the same discriminants as
6218 -- the root record type, stored discriminants are the same as regular
6219 -- discriminants, and are said to be implicit. However, if any discriminant
6220 -- in the root type was renamed in the derived type, then the derived
6221 -- type will contain explicit stored discriminants. Explicit stored
6222 -- discriminants are discriminants in addition to the semantically visible
6223 -- discriminants defined for the derived type. Stored discriminants are
6224 -- used by Gigi to figure out what are the physical discriminants in
6225 -- objects of the derived type (see precise definition in einfo.ads).
6226 -- As an example, consider the following:
6228 -- type R (D1, D2, D3 : Int) is record ... end record;
6229 -- type T1 is new R;
6230 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
6231 -- type T3 is new T2;
6232 -- type T4 (Y : Int) is new T3 (Y, 99);
6234 -- The following table summarizes the discriminants and stored
6235 -- discriminants in R and T1 through T4.
6237 -- Type Discrim Stored Discrim Comment
6238 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
6239 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
6240 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
6241 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
6242 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
6244 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
6245 -- find the corresponding discriminant in the parent type, while
6246 -- Original_Record_Component (abbreviated ORC below), the actual physical
6247 -- component that is renamed. Finally the field Is_Completely_Hidden
6248 -- (abbreviated ICH below) is set for all explicit stored discriminants
6249 -- (see einfo.ads for more info). For the above example this gives:
6251 -- Discrim CD ORC ICH
6252 -- ^^^^^^^ ^^ ^^^ ^^^
6253 -- D1 in R empty itself no
6254 -- D2 in R empty itself no
6255 -- D3 in R empty itself no
6257 -- D1 in T1 D1 in R itself no
6258 -- D2 in T1 D2 in R itself no
6259 -- D3 in T1 D3 in R itself no
6261 -- X1 in T2 D3 in T1 D3 in T2 no
6262 -- X2 in T2 D1 in T1 D1 in T2 no
6263 -- D1 in T2 empty itself yes
6264 -- D2 in T2 empty itself yes
6265 -- D3 in T2 empty itself yes
6267 -- X1 in T3 X1 in T2 D3 in T3 no
6268 -- X2 in T3 X2 in T2 D1 in T3 no
6269 -- D1 in T3 empty itself yes
6270 -- D2 in T3 empty itself yes
6271 -- D3 in T3 empty itself yes
6273 -- Y in T4 X1 in T3 D3 in T3 no
6274 -- D1 in T3 empty itself yes
6275 -- D2 in T3 empty itself yes
6276 -- D3 in T3 empty itself yes
6278 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
6280 -- Type derivation for tagged types is fairly straightforward. If no
6281 -- discriminants are specified by the derived type, these are inherited
6282 -- from the parent. No explicit stored discriminants are ever necessary.
6283 -- The only manipulation that is done to the tree is that of adding a
6284 -- _parent field with parent type and constrained to the same constraint
6285 -- specified for the parent in the derived type definition. For instance:
6287 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
6288 -- type T1 is new R with null record;
6289 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
6291 -- are changed into:
6293 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
6294 -- _parent : R (D1, D2, D3);
6297 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
6298 -- _parent : T1 (X2, 88, X1);
6301 -- The discriminants actually present in R, T1 and T2 as well as their CD,
6302 -- ORC and ICH fields are:
6304 -- Discrim CD ORC ICH
6305 -- ^^^^^^^ ^^ ^^^ ^^^
6306 -- D1 in R empty itself no
6307 -- D2 in R empty itself no
6308 -- D3 in R empty itself no
6310 -- D1 in T1 D1 in R D1 in R no
6311 -- D2 in T1 D2 in R D2 in R no
6312 -- D3 in T1 D3 in R D3 in R no
6314 -- X1 in T2 D3 in T1 D3 in R no
6315 -- X2 in T2 D1 in T1 D1 in R no
6317 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
6319 -- Regardless of whether we dealing with a tagged or untagged type
6320 -- we will transform all derived type declarations of the form
6322 -- type T is new R (...) [with ...];
6324 -- subtype S is R (...);
6325 -- type T is new S [with ...];
6327 -- type BT is new R [with ...];
6328 -- subtype T is BT (...);
6330 -- That is, the base derived type is constrained only if it has no
6331 -- discriminants. The reason for doing this is that GNAT's semantic model
6332 -- assumes that a base type with discriminants is unconstrained.
6334 -- Note that, strictly speaking, the above transformation is not always
6335 -- correct. Consider for instance the following excerpt from ACVC b34011a:
6337 -- procedure B34011A is
6338 -- type REC (D : integer := 0) is record
6343 -- type T6 is new Rec;
6344 -- function F return T6;
6349 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
6352 -- The definition of Q6.U is illegal. However transforming Q6.U into
6354 -- type BaseU is new T6;
6355 -- subtype U is BaseU (Q6.F.I)
6357 -- turns U into a legal subtype, which is incorrect. To avoid this problem
6358 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
6359 -- the transformation described above.
6361 -- There is another instance where the above transformation is incorrect.
6365 -- type Base (D : Integer) is tagged null record;
6366 -- procedure P (X : Base);
6368 -- type Der is new Base (2) with null record;
6369 -- procedure P (X : Der);
6372 -- Then the above transformation turns this into
6374 -- type Der_Base is new Base with null record;
6375 -- -- procedure P (X : Base) is implicitly inherited here
6376 -- -- as procedure P (X : Der_Base).
6378 -- subtype Der is Der_Base (2);
6379 -- procedure P (X : Der);
6380 -- -- The overriding of P (X : Der_Base) is illegal since we
6381 -- -- have a parameter conformance problem.
6383 -- To get around this problem, after having semantically processed Der_Base
6384 -- and the rewritten subtype declaration for Der, we copy Der_Base field
6385 -- Discriminant_Constraint from Der so that when parameter conformance is
6386 -- checked when P is overridden, no semantic errors are flagged.
6388 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
6390 -- Regardless of whether we are dealing with a tagged or untagged type
6391 -- we will transform all derived type declarations of the form
6393 -- type R (D1, .., Dn : ...) is [tagged] record ...;
6394 -- type T is new R [with ...];
6396 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
6398 -- The reason for such transformation is that it allows us to implement a
6399 -- very clean form of component inheritance as explained below.
6401 -- Note that this transformation is not achieved by direct tree rewriting
6402 -- and manipulation, but rather by redoing the semantic actions that the
6403 -- above transformation will entail. This is done directly in routine
6404 -- Inherit_Components.
6406 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
6408 -- In both tagged and untagged derived types, regular non discriminant
6409 -- components are inherited in the derived type from the parent type. In
6410 -- the absence of discriminants component, inheritance is straightforward
6411 -- as components can simply be copied from the parent.
6413 -- If the parent has discriminants, inheriting components constrained with
6414 -- these discriminants requires caution. Consider the following example:
6416 -- type R (D1, D2 : Positive) is [tagged] record
6417 -- S : String (D1 .. D2);
6420 -- type T1 is new R [with null record];
6421 -- type T2 (X : positive) is new R (1, X) [with null record];
6423 -- As explained in 6. above, T1 is rewritten as
6424 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
6425 -- which makes the treatment for T1 and T2 identical.
6427 -- What we want when inheriting S, is that references to D1 and D2 in R are
6428 -- replaced with references to their correct constraints, i.e. D1 and D2 in
6429 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
6430 -- with either discriminant references in the derived type or expressions.
6431 -- This replacement is achieved as follows: before inheriting R's
6432 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
6433 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
6434 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
6435 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
6436 -- by String (1 .. X).
6438 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
6440 -- We explain here the rules governing private type extensions relevant to
6441 -- type derivation. These rules are explained on the following example:
6443 -- type D [(...)] is new A [(...)] with private; <-- partial view
6444 -- type D [(...)] is new P [(...)] with null record; <-- full view
6446 -- Type A is called the ancestor subtype of the private extension.
6447 -- Type P is the parent type of the full view of the private extension. It
6448 -- must be A or a type derived from A.
6450 -- The rules concerning the discriminants of private type extensions are
6453 -- o If a private extension inherits known discriminants from the ancestor
6454 -- subtype, then the full view shall also inherit its discriminants from
6455 -- the ancestor subtype and the parent subtype of the full view shall be
6456 -- constrained if and only if the ancestor subtype is constrained.
6458 -- o If a partial view has unknown discriminants, then the full view may
6459 -- define a definite or an indefinite subtype, with or without
6462 -- o If a partial view has neither known nor unknown discriminants, then
6463 -- the full view shall define a definite subtype.
6465 -- o If the ancestor subtype of a private extension has constrained
6466 -- discriminants, then the parent subtype of the full view shall impose a
6467 -- statically matching constraint on those discriminants.
6469 -- This means that only the following forms of private extensions are
6472 -- type D is new A with private; <-- partial view
6473 -- type D is new P with null record; <-- full view
6475 -- If A has no discriminants than P has no discriminants, otherwise P must
6476 -- inherit A's discriminants.
6478 -- type D is new A (...) with private; <-- partial view
6479 -- type D is new P (:::) with null record; <-- full view
6481 -- P must inherit A's discriminants and (...) and (:::) must statically
6484 -- subtype A is R (...);
6485 -- type D is new A with private; <-- partial view
6486 -- type D is new P with null record; <-- full view
6488 -- P must have inherited R's discriminants and must be derived from A or
6489 -- any of its subtypes.
6491 -- type D (..) is new A with private; <-- partial view
6492 -- type D (..) is new P [(:::)] with null record; <-- full view
6494 -- No specific constraints on P's discriminants or constraint (:::).
6495 -- Note that A can be unconstrained, but the parent subtype P must either
6496 -- be constrained or (:::) must be present.
6498 -- type D (..) is new A [(...)] with private; <-- partial view
6499 -- type D (..) is new P [(:::)] with null record; <-- full view
6501 -- P's constraints on A's discriminants must statically match those
6502 -- imposed by (...).
6504 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
6506 -- The full view of a private extension is handled exactly as described
6507 -- above. The model chose for the private view of a private extension is
6508 -- the same for what concerns discriminants (i.e. they receive the same
6509 -- treatment as in the tagged case). However, the private view of the
6510 -- private extension always inherits the components of the parent base,
6511 -- without replacing any discriminant reference. Strictly speaking this is
6512 -- incorrect. However, Gigi never uses this view to generate code so this
6513 -- is a purely semantic issue. In theory, a set of transformations similar
6514 -- to those given in 5. and 6. above could be applied to private views of
6515 -- private extensions to have the same model of component inheritance as
6516 -- for non private extensions. However, this is not done because it would
6517 -- further complicate private type processing. Semantically speaking, this
6518 -- leaves us in an uncomfortable situation. As an example consider:
6521 -- type R (D : integer) is tagged record
6522 -- S : String (1 .. D);
6524 -- procedure P (X : R);
6525 -- type T is new R (1) with private;
6527 -- type T is new R (1) with null record;
6530 -- This is transformed into:
6533 -- type R (D : integer) is tagged record
6534 -- S : String (1 .. D);
6536 -- procedure P (X : R);
6537 -- type T is new R (1) with private;
6539 -- type BaseT is new R with null record;
6540 -- subtype T is BaseT (1);
6543 -- (strictly speaking the above is incorrect Ada)
6545 -- From the semantic standpoint the private view of private extension T
6546 -- should be flagged as constrained since one can clearly have
6550 -- in a unit withing Pack. However, when deriving subprograms for the
6551 -- private view of private extension T, T must be seen as unconstrained
6552 -- since T has discriminants (this is a constraint of the current
6553 -- subprogram derivation model). Thus, when processing the private view of
6554 -- a private extension such as T, we first mark T as unconstrained, we
6555 -- process it, we perform program derivation and just before returning from
6556 -- Build_Derived_Record_Type we mark T as constrained.
6558 -- ??? Are there are other uncomfortable cases that we will have to
6561 -- 10. RECORD_TYPE_WITH_PRIVATE complications
6563 -- Types that are derived from a visible record type and have a private
6564 -- extension present other peculiarities. They behave mostly like private
6565 -- types, but if they have primitive operations defined, these will not
6566 -- have the proper signatures for further inheritance, because other
6567 -- primitive operations will use the implicit base that we define for
6568 -- private derivations below. This affect subprogram inheritance (see
6569 -- Derive_Subprograms for details). We also derive the implicit base from
6570 -- the base type of the full view, so that the implicit base is a record
6571 -- type and not another private type, This avoids infinite loops.
6573 procedure Build_Derived_Record_Type
6575 Parent_Type : Entity_Id;
6576 Derived_Type : Entity_Id;
6577 Derive_Subps : Boolean := True)
6579 Loc : constant Source_Ptr := Sloc (N);
6580 Parent_Base : Entity_Id;
6583 Discrim : Entity_Id;
6584 Last_Discrim : Entity_Id;
6587 Discs : Elist_Id := New_Elmt_List;
6588 -- An empty Discs list means that there were no constraints in the
6589 -- subtype indication or that there was an error processing it.
6591 Assoc_List : Elist_Id;
6592 New_Discrs : Elist_Id;
6593 New_Base : Entity_Id;
6595 New_Indic : Node_Id;
6597 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
6598 Discriminant_Specs : constant Boolean :=
6599 Present (Discriminant_Specifications (N));
6600 Private_Extension : constant Boolean :=
6601 Nkind (N) = N_Private_Extension_Declaration;
6603 Constraint_Present : Boolean;
6604 Inherit_Discrims : Boolean := False;
6605 Save_Etype : Entity_Id;
6606 Save_Discr_Constr : Elist_Id;
6607 Save_Next_Entity : Entity_Id;
6610 if Ekind (Parent_Type) = E_Record_Type_With_Private
6611 and then Present (Full_View (Parent_Type))
6612 and then Has_Discriminants (Parent_Type)
6614 Parent_Base := Base_Type (Full_View (Parent_Type));
6616 Parent_Base := Base_Type (Parent_Type);
6619 -- Before we start the previously documented transformations, here is
6620 -- little fix for size and alignment of tagged types. Normally when we
6621 -- derive type D from type P, we copy the size and alignment of P as the
6622 -- default for D, and in the absence of explicit representation clauses
6623 -- for D, the size and alignment are indeed the same as the parent.
6625 -- But this is wrong for tagged types, since fields may be added, and
6626 -- the default size may need to be larger, and the default alignment may
6627 -- need to be larger.
6629 -- We therefore reset the size and alignment fields in the tagged case.
6630 -- Note that the size and alignment will in any case be at least as
6631 -- large as the parent type (since the derived type has a copy of the
6632 -- parent type in the _parent field)
6634 -- The type is also marked as being tagged here, which is needed when
6635 -- processing components with a self-referential anonymous access type
6636 -- in the call to Check_Anonymous_Access_Components below. Note that
6637 -- this flag is also set later on for completeness.
6640 Set_Is_Tagged_Type (Derived_Type);
6641 Init_Size_Align (Derived_Type);
6644 -- STEP 0a: figure out what kind of derived type declaration we have
6646 if Private_Extension then
6648 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
6651 Type_Def := Type_Definition (N);
6653 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
6654 -- Parent_Base can be a private type or private extension. However,
6655 -- for tagged types with an extension the newly added fields are
6656 -- visible and hence the Derived_Type is always an E_Record_Type.
6657 -- (except that the parent may have its own private fields).
6658 -- For untagged types we preserve the Ekind of the Parent_Base.
6660 if Present (Record_Extension_Part (Type_Def)) then
6661 Set_Ekind (Derived_Type, E_Record_Type);
6663 -- Create internal access types for components with anonymous
6666 if Ada_Version >= Ada_05 then
6667 Check_Anonymous_Access_Components
6668 (N, Derived_Type, Derived_Type,
6669 Component_List (Record_Extension_Part (Type_Def)));
6673 Set_Ekind (Derived_Type, Ekind (Parent_Base));
6677 -- Indic can either be an N_Identifier if the subtype indication
6678 -- contains no constraint or an N_Subtype_Indication if the subtype
6679 -- indication has a constraint.
6681 Indic := Subtype_Indication (Type_Def);
6682 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
6684 -- Check that the type has visible discriminants. The type may be
6685 -- a private type with unknown discriminants whose full view has
6686 -- discriminants which are invisible.
6688 if Constraint_Present then
6689 if not Has_Discriminants (Parent_Base)
6691 (Has_Unknown_Discriminants (Parent_Base)
6692 and then Is_Private_Type (Parent_Base))
6695 ("invalid constraint: type has no discriminant",
6696 Constraint (Indic));
6698 Constraint_Present := False;
6699 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
6701 elsif Is_Constrained (Parent_Type) then
6703 ("invalid constraint: parent type is already constrained",
6704 Constraint (Indic));
6706 Constraint_Present := False;
6707 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
6711 -- STEP 0b: If needed, apply transformation given in point 5. above
6713 if not Private_Extension
6714 and then Has_Discriminants (Parent_Type)
6715 and then not Discriminant_Specs
6716 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
6718 -- First, we must analyze the constraint (see comment in point 5.)
6720 if Constraint_Present then
6721 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
6723 if Has_Discriminants (Derived_Type)
6724 and then Has_Private_Declaration (Derived_Type)
6725 and then Present (Discriminant_Constraint (Derived_Type))
6727 -- Verify that constraints of the full view statically match
6728 -- those given in the partial view.
6734 C1 := First_Elmt (New_Discrs);
6735 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
6736 while Present (C1) and then Present (C2) loop
6737 if Fully_Conformant_Expressions (Node (C1), Node (C2))
6739 (Is_OK_Static_Expression (Node (C1))
6741 Is_OK_Static_Expression (Node (C2))
6743 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
6749 "constraint not conformant to previous declaration",
6760 -- Insert and analyze the declaration for the unconstrained base type
6762 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
6765 Make_Full_Type_Declaration (Loc,
6766 Defining_Identifier => New_Base,
6768 Make_Derived_Type_Definition (Loc,
6769 Abstract_Present => Abstract_Present (Type_Def),
6770 Limited_Present => Limited_Present (Type_Def),
6771 Subtype_Indication =>
6772 New_Occurrence_Of (Parent_Base, Loc),
6773 Record_Extension_Part =>
6774 Relocate_Node (Record_Extension_Part (Type_Def)),
6775 Interface_List => Interface_List (Type_Def)));
6777 Set_Parent (New_Decl, Parent (N));
6778 Mark_Rewrite_Insertion (New_Decl);
6779 Insert_Before (N, New_Decl);
6781 -- Note that this call passes False for the Derive_Subps parameter
6782 -- because subprogram derivation is deferred until after creating
6783 -- the subtype (see below).
6786 (New_Decl, Parent_Base, New_Base,
6787 Is_Completion => True, Derive_Subps => False);
6789 -- ??? This needs re-examination to determine whether the
6790 -- above call can simply be replaced by a call to Analyze.
6792 Set_Analyzed (New_Decl);
6794 -- Insert and analyze the declaration for the constrained subtype
6796 if Constraint_Present then
6798 Make_Subtype_Indication (Loc,
6799 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
6800 Constraint => Relocate_Node (Constraint (Indic)));
6804 Constr_List : constant List_Id := New_List;
6809 C := First_Elmt (Discriminant_Constraint (Parent_Type));
6810 while Present (C) loop
6813 -- It is safe here to call New_Copy_Tree since
6814 -- Force_Evaluation was called on each constraint in
6815 -- Build_Discriminant_Constraints.
6817 Append (New_Copy_Tree (Expr), To => Constr_List);
6823 Make_Subtype_Indication (Loc,
6824 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
6826 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
6831 Make_Subtype_Declaration (Loc,
6832 Defining_Identifier => Derived_Type,
6833 Subtype_Indication => New_Indic));
6837 -- Derivation of subprograms must be delayed until the full subtype
6838 -- has been established to ensure proper overriding of subprograms
6839 -- inherited by full types. If the derivations occurred as part of
6840 -- the call to Build_Derived_Type above, then the check for type
6841 -- conformance would fail because earlier primitive subprograms
6842 -- could still refer to the full type prior the change to the new
6843 -- subtype and hence would not match the new base type created here.
6845 Derive_Subprograms (Parent_Type, Derived_Type);
6847 -- For tagged types the Discriminant_Constraint of the new base itype
6848 -- is inherited from the first subtype so that no subtype conformance
6849 -- problem arise when the first subtype overrides primitive
6850 -- operations inherited by the implicit base type.
6853 Set_Discriminant_Constraint
6854 (New_Base, Discriminant_Constraint (Derived_Type));
6860 -- If we get here Derived_Type will have no discriminants or it will be
6861 -- a discriminated unconstrained base type.
6863 -- STEP 1a: perform preliminary actions/checks for derived tagged types
6867 -- The parent type is frozen for non-private extensions (RM 13.14(7))
6868 -- The declaration of a specific descendant of an interface type
6869 -- freezes the interface type (RM 13.14).
6871 if not Private_Extension
6872 or else Is_Interface (Parent_Base)
6874 Freeze_Before (N, Parent_Type);
6877 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
6878 -- cannot be declared at a deeper level than its parent type is
6879 -- removed. The check on derivation within a generic body is also
6880 -- relaxed, but there's a restriction that a derived tagged type
6881 -- cannot be declared in a generic body if it's derived directly
6882 -- or indirectly from a formal type of that generic.
6884 if Ada_Version >= Ada_05 then
6885 if Present (Enclosing_Generic_Body (Derived_Type)) then
6887 Ancestor_Type : Entity_Id;
6890 -- Check to see if any ancestor of the derived type is a
6893 Ancestor_Type := Parent_Type;
6894 while not Is_Generic_Type (Ancestor_Type)
6895 and then Etype (Ancestor_Type) /= Ancestor_Type
6897 Ancestor_Type := Etype (Ancestor_Type);
6900 -- If the derived type does have a formal type as an
6901 -- ancestor, then it's an error if the derived type is
6902 -- declared within the body of the generic unit that
6903 -- declares the formal type in its generic formal part. It's
6904 -- sufficient to check whether the ancestor type is declared
6905 -- inside the same generic body as the derived type (such as
6906 -- within a nested generic spec), in which case the
6907 -- derivation is legal. If the formal type is declared
6908 -- outside of that generic body, then it's guaranteed that
6909 -- the derived type is declared within the generic body of
6910 -- the generic unit declaring the formal type.
6912 if Is_Generic_Type (Ancestor_Type)
6913 and then Enclosing_Generic_Body (Ancestor_Type) /=
6914 Enclosing_Generic_Body (Derived_Type)
6917 ("parent type of& must not be descendant of formal type"
6918 & " of an enclosing generic body",
6919 Indic, Derived_Type);
6924 elsif Type_Access_Level (Derived_Type) /=
6925 Type_Access_Level (Parent_Type)
6926 and then not Is_Generic_Type (Derived_Type)
6928 if Is_Controlled (Parent_Type) then
6930 ("controlled type must be declared at the library level",
6934 ("type extension at deeper accessibility level than parent",
6940 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
6944 and then GB /= Enclosing_Generic_Body (Parent_Base)
6947 ("parent type of& must not be outside generic body"
6949 Indic, Derived_Type);
6955 -- Ada 2005 (AI-251)
6957 if Ada_Version = Ada_05
6960 -- "The declaration of a specific descendant of an interface type
6961 -- freezes the interface type" (RM 13.14).
6966 if Is_Non_Empty_List (Interface_List (Type_Def)) then
6967 Iface := First (Interface_List (Type_Def));
6968 while Present (Iface) loop
6969 Freeze_Before (N, Etype (Iface));
6976 -- STEP 1b : preliminary cleanup of the full view of private types
6978 -- If the type is already marked as having discriminants, then it's the
6979 -- completion of a private type or private extension and we need to
6980 -- retain the discriminants from the partial view if the current
6981 -- declaration has Discriminant_Specifications so that we can verify
6982 -- conformance. However, we must remove any existing components that
6983 -- were inherited from the parent (and attached in Copy_And_Swap)
6984 -- because the full type inherits all appropriate components anyway, and
6985 -- we do not want the partial view's components interfering.
6987 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
6988 Discrim := First_Discriminant (Derived_Type);
6990 Last_Discrim := Discrim;
6991 Next_Discriminant (Discrim);
6992 exit when No (Discrim);
6995 Set_Last_Entity (Derived_Type, Last_Discrim);
6997 -- In all other cases wipe out the list of inherited components (even
6998 -- inherited discriminants), it will be properly rebuilt here.
7001 Set_First_Entity (Derived_Type, Empty);
7002 Set_Last_Entity (Derived_Type, Empty);
7005 -- STEP 1c: Initialize some flags for the Derived_Type
7007 -- The following flags must be initialized here so that
7008 -- Process_Discriminants can check that discriminants of tagged types do
7009 -- not have a default initial value and that access discriminants are
7010 -- only specified for limited records. For completeness, these flags are
7011 -- also initialized along with all the other flags below.
7013 -- AI-419: Limitedness is not inherited from an interface parent, so to
7014 -- be limited in that case the type must be explicitly declared as
7015 -- limited. However, task and protected interfaces are always limited.
7017 if Limited_Present (Type_Def) then
7018 Set_Is_Limited_Record (Derived_Type);
7020 elsif Is_Limited_Record (Parent_Type)
7021 or else (Present (Full_View (Parent_Type))
7022 and then Is_Limited_Record (Full_View (Parent_Type)))
7024 if not Is_Interface (Parent_Type)
7025 or else Is_Synchronized_Interface (Parent_Type)
7026 or else Is_Protected_Interface (Parent_Type)
7027 or else Is_Task_Interface (Parent_Type)
7029 Set_Is_Limited_Record (Derived_Type);
7033 -- STEP 2a: process discriminants of derived type if any
7035 Push_Scope (Derived_Type);
7037 if Discriminant_Specs then
7038 Set_Has_Unknown_Discriminants (Derived_Type, False);
7040 -- The following call initializes fields Has_Discriminants and
7041 -- Discriminant_Constraint, unless we are processing the completion
7042 -- of a private type declaration.
7044 Check_Or_Process_Discriminants (N, Derived_Type);
7046 -- For non-tagged types the constraint on the Parent_Type must be
7047 -- present and is used to rename the discriminants.
7049 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
7050 Error_Msg_N ("untagged parent must have discriminants", Indic);
7052 elsif not Is_Tagged and then not Constraint_Present then
7054 ("discriminant constraint needed for derived untagged records",
7057 -- Otherwise the parent subtype must be constrained unless we have a
7058 -- private extension.
7060 elsif not Constraint_Present
7061 and then not Private_Extension
7062 and then not Is_Constrained (Parent_Type)
7065 ("unconstrained type not allowed in this context", Indic);
7067 elsif Constraint_Present then
7068 -- The following call sets the field Corresponding_Discriminant
7069 -- for the discriminants in the Derived_Type.
7071 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
7073 -- For untagged types all new discriminants must rename
7074 -- discriminants in the parent. For private extensions new
7075 -- discriminants cannot rename old ones (implied by [7.3(13)]).
7077 Discrim := First_Discriminant (Derived_Type);
7078 while Present (Discrim) loop
7080 and then No (Corresponding_Discriminant (Discrim))
7083 ("new discriminants must constrain old ones", Discrim);
7085 elsif Private_Extension
7086 and then Present (Corresponding_Discriminant (Discrim))
7089 ("only static constraints allowed for parent"
7090 & " discriminants in the partial view", Indic);
7094 -- If a new discriminant is used in the constraint, then its
7095 -- subtype must be statically compatible with the parent
7096 -- discriminant's subtype (3.7(15)).
7098 if Present (Corresponding_Discriminant (Discrim))
7100 not Subtypes_Statically_Compatible
7102 Etype (Corresponding_Discriminant (Discrim)))
7105 ("subtype must be compatible with parent discriminant",
7109 Next_Discriminant (Discrim);
7112 -- Check whether the constraints of the full view statically
7113 -- match those imposed by the parent subtype [7.3(13)].
7115 if Present (Stored_Constraint (Derived_Type)) then
7120 C1 := First_Elmt (Discs);
7121 C2 := First_Elmt (Stored_Constraint (Derived_Type));
7122 while Present (C1) and then Present (C2) loop
7124 Fully_Conformant_Expressions (Node (C1), Node (C2))
7127 ("not conformant with previous declaration",
7138 -- STEP 2b: No new discriminants, inherit discriminants if any
7141 if Private_Extension then
7142 Set_Has_Unknown_Discriminants
7144 Has_Unknown_Discriminants (Parent_Type)
7145 or else Unknown_Discriminants_Present (N));
7147 -- The partial view of the parent may have unknown discriminants,
7148 -- but if the full view has discriminants and the parent type is
7149 -- in scope they must be inherited.
7151 elsif Has_Unknown_Discriminants (Parent_Type)
7153 (not Has_Discriminants (Parent_Type)
7154 or else not In_Open_Scopes (Scope (Parent_Type)))
7156 Set_Has_Unknown_Discriminants (Derived_Type);
7159 if not Has_Unknown_Discriminants (Derived_Type)
7160 and then not Has_Unknown_Discriminants (Parent_Base)
7161 and then Has_Discriminants (Parent_Type)
7163 Inherit_Discrims := True;
7164 Set_Has_Discriminants
7165 (Derived_Type, True);
7166 Set_Discriminant_Constraint
7167 (Derived_Type, Discriminant_Constraint (Parent_Base));
7170 -- The following test is true for private types (remember
7171 -- transformation 5. is not applied to those) and in an error
7174 if Constraint_Present then
7175 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
7178 -- For now mark a new derived type as constrained only if it has no
7179 -- discriminants. At the end of Build_Derived_Record_Type we properly
7180 -- set this flag in the case of private extensions. See comments in
7181 -- point 9. just before body of Build_Derived_Record_Type.
7185 not (Inherit_Discrims
7186 or else Has_Unknown_Discriminants (Derived_Type)));
7189 -- STEP 3: initialize fields of derived type
7191 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
7192 Set_Stored_Constraint (Derived_Type, No_Elist);
7194 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
7195 -- but cannot be interfaces
7197 if not Private_Extension
7198 and then Ekind (Derived_Type) /= E_Private_Type
7199 and then Ekind (Derived_Type) /= E_Limited_Private_Type
7201 if Interface_Present (Type_Def) then
7202 Analyze_Interface_Declaration (Derived_Type, Type_Def);
7205 Set_Interfaces (Derived_Type, No_Elist);
7208 -- Fields inherited from the Parent_Type
7211 (Derived_Type, Einfo.Discard_Names (Parent_Type));
7212 Set_Has_Specified_Layout
7213 (Derived_Type, Has_Specified_Layout (Parent_Type));
7214 Set_Is_Limited_Composite
7215 (Derived_Type, Is_Limited_Composite (Parent_Type));
7216 Set_Is_Private_Composite
7217 (Derived_Type, Is_Private_Composite (Parent_Type));
7219 -- Fields inherited from the Parent_Base
7221 Set_Has_Controlled_Component
7222 (Derived_Type, Has_Controlled_Component (Parent_Base));
7223 Set_Has_Non_Standard_Rep
7224 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7225 Set_Has_Primitive_Operations
7226 (Derived_Type, Has_Primitive_Operations (Parent_Base));
7228 -- Fields inherited from the Parent_Base in the non-private case
7230 if Ekind (Derived_Type) = E_Record_Type then
7231 Set_Has_Complex_Representation
7232 (Derived_Type, Has_Complex_Representation (Parent_Base));
7235 -- Fields inherited from the Parent_Base for record types
7237 if Is_Record_Type (Derived_Type) then
7239 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7240 -- Parent_Base can be a private type or private extension.
7242 if Present (Full_View (Parent_Base)) then
7243 Set_OK_To_Reorder_Components
7245 OK_To_Reorder_Components (Full_View (Parent_Base)));
7246 Set_Reverse_Bit_Order
7247 (Derived_Type, Reverse_Bit_Order (Full_View (Parent_Base)));
7249 Set_OK_To_Reorder_Components
7250 (Derived_Type, OK_To_Reorder_Components (Parent_Base));
7251 Set_Reverse_Bit_Order
7252 (Derived_Type, Reverse_Bit_Order (Parent_Base));
7256 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7258 if not Is_Controlled (Parent_Type) then
7259 Set_Finalize_Storage_Only
7260 (Derived_Type, Finalize_Storage_Only (Parent_Type));
7263 -- Set fields for private derived types
7265 if Is_Private_Type (Derived_Type) then
7266 Set_Depends_On_Private (Derived_Type, True);
7267 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7269 -- Inherit fields from non private record types. If this is the
7270 -- completion of a derivation from a private type, the parent itself
7271 -- is private, and the attributes come from its full view, which must
7275 if Is_Private_Type (Parent_Base)
7276 and then not Is_Record_Type (Parent_Base)
7278 Set_Component_Alignment
7279 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
7281 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
7283 Set_Component_Alignment
7284 (Derived_Type, Component_Alignment (Parent_Base));
7286 (Derived_Type, C_Pass_By_Copy (Parent_Base));
7290 -- Set fields for tagged types
7293 Set_Primitive_Operations (Derived_Type, New_Elmt_List);
7295 -- All tagged types defined in Ada.Finalization are controlled
7297 if Chars (Scope (Derived_Type)) = Name_Finalization
7298 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
7299 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
7301 Set_Is_Controlled (Derived_Type);
7303 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
7306 -- Minor optimization: there is no need to generate the class-wide
7307 -- entity associated with an underlying record view.
7309 if not Is_Underlying_Record_View (Derived_Type) then
7310 Make_Class_Wide_Type (Derived_Type);
7313 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
7315 if Has_Discriminants (Derived_Type)
7316 and then Constraint_Present
7318 Set_Stored_Constraint
7319 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
7322 if Ada_Version >= Ada_05 then
7324 Ifaces_List : Elist_Id;
7327 -- Checks rules 3.9.4 (13/2 and 14/2)
7329 if Comes_From_Source (Derived_Type)
7330 and then not Is_Private_Type (Derived_Type)
7331 and then Is_Interface (Parent_Type)
7332 and then not Is_Interface (Derived_Type)
7334 if Is_Task_Interface (Parent_Type) then
7336 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
7339 elsif Is_Protected_Interface (Parent_Type) then
7341 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
7346 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
7348 Check_Interfaces (N, Type_Def);
7350 -- Ada 2005 (AI-251): Collect the list of progenitors that are
7351 -- not already in the parents.
7355 Ifaces_List => Ifaces_List,
7356 Exclude_Parents => True);
7358 Set_Interfaces (Derived_Type, Ifaces_List);
7363 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
7364 Set_Has_Non_Standard_Rep
7365 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7368 -- STEP 4: Inherit components from the parent base and constrain them.
7369 -- Apply the second transformation described in point 6. above.
7371 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
7372 or else not Has_Discriminants (Parent_Type)
7373 or else not Is_Constrained (Parent_Type)
7377 Constrs := Discriminant_Constraint (Parent_Type);
7382 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
7384 -- STEP 5a: Copy the parent record declaration for untagged types
7386 if not Is_Tagged then
7388 -- Discriminant_Constraint (Derived_Type) has been properly
7389 -- constructed. Save it and temporarily set it to Empty because we
7390 -- do not want the call to New_Copy_Tree below to mess this list.
7392 if Has_Discriminants (Derived_Type) then
7393 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
7394 Set_Discriminant_Constraint (Derived_Type, No_Elist);
7396 Save_Discr_Constr := No_Elist;
7399 -- Save the Etype field of Derived_Type. It is correctly set now,
7400 -- but the call to New_Copy tree may remap it to point to itself,
7401 -- which is not what we want. Ditto for the Next_Entity field.
7403 Save_Etype := Etype (Derived_Type);
7404 Save_Next_Entity := Next_Entity (Derived_Type);
7406 -- Assoc_List maps all stored discriminants in the Parent_Base to
7407 -- stored discriminants in the Derived_Type. It is fundamental that
7408 -- no types or itypes with discriminants other than the stored
7409 -- discriminants appear in the entities declared inside
7410 -- Derived_Type, since the back end cannot deal with it.
7414 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
7416 -- Restore the fields saved prior to the New_Copy_Tree call
7417 -- and compute the stored constraint.
7419 Set_Etype (Derived_Type, Save_Etype);
7420 Set_Next_Entity (Derived_Type, Save_Next_Entity);
7422 if Has_Discriminants (Derived_Type) then
7423 Set_Discriminant_Constraint
7424 (Derived_Type, Save_Discr_Constr);
7425 Set_Stored_Constraint
7426 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
7427 Replace_Components (Derived_Type, New_Decl);
7430 -- Insert the new derived type declaration
7432 Rewrite (N, New_Decl);
7434 -- STEP 5b: Complete the processing for record extensions in generics
7436 -- There is no completion for record extensions declared in the
7437 -- parameter part of a generic, so we need to complete processing for
7438 -- these generic record extensions here. The Record_Type_Definition call
7439 -- will change the Ekind of the components from E_Void to E_Component.
7441 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
7442 Record_Type_Definition (Empty, Derived_Type);
7444 -- STEP 5c: Process the record extension for non private tagged types
7446 elsif not Private_Extension then
7448 -- Add the _parent field in the derived type
7450 Expand_Record_Extension (Derived_Type, Type_Def);
7452 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
7453 -- implemented interfaces if we are in expansion mode
7456 and then Has_Interfaces (Derived_Type)
7458 Add_Interface_Tag_Components (N, Derived_Type);
7461 -- Analyze the record extension
7463 Record_Type_Definition
7464 (Record_Extension_Part (Type_Def), Derived_Type);
7469 -- Nothing else to do if there is an error in the derivation.
7470 -- An unusual case: the full view may be derived from a type in an
7471 -- instance, when the partial view was used illegally as an actual
7472 -- in that instance, leading to a circular definition.
7474 if Etype (Derived_Type) = Any_Type
7475 or else Etype (Parent_Type) = Derived_Type
7480 -- Set delayed freeze and then derive subprograms, we need to do
7481 -- this in this order so that derived subprograms inherit the
7482 -- derived freeze if necessary.
7484 Set_Has_Delayed_Freeze (Derived_Type);
7486 if Derive_Subps then
7487 Derive_Subprograms (Parent_Type, Derived_Type);
7490 -- If we have a private extension which defines a constrained derived
7491 -- type mark as constrained here after we have derived subprograms. See
7492 -- comment on point 9. just above the body of Build_Derived_Record_Type.
7494 if Private_Extension and then Inherit_Discrims then
7495 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
7496 Set_Is_Constrained (Derived_Type, True);
7497 Set_Discriminant_Constraint (Derived_Type, Discs);
7499 elsif Is_Constrained (Parent_Type) then
7501 (Derived_Type, True);
7502 Set_Discriminant_Constraint
7503 (Derived_Type, Discriminant_Constraint (Parent_Type));
7507 -- Update the class-wide type, which shares the now-completed entity
7508 -- list with its specific type. In case of underlying record views,
7509 -- we do not generate the corresponding class wide entity.
7512 and then not Is_Underlying_Record_View (Derived_Type)
7515 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
7517 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
7520 -- Update the scope of anonymous access types of discriminants and other
7521 -- components, to prevent scope anomalies in gigi, when the derivation
7522 -- appears in a scope nested within that of the parent.
7528 D := First_Entity (Derived_Type);
7529 while Present (D) loop
7530 if Ekind (D) = E_Discriminant
7531 or else Ekind (D) = E_Component
7533 if Is_Itype (Etype (D))
7534 and then Ekind (Etype (D)) = E_Anonymous_Access_Type
7536 Set_Scope (Etype (D), Current_Scope);
7543 end Build_Derived_Record_Type;
7545 ------------------------
7546 -- Build_Derived_Type --
7547 ------------------------
7549 procedure Build_Derived_Type
7551 Parent_Type : Entity_Id;
7552 Derived_Type : Entity_Id;
7553 Is_Completion : Boolean;
7554 Derive_Subps : Boolean := True)
7556 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
7559 -- Set common attributes
7561 Set_Scope (Derived_Type, Current_Scope);
7563 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7564 Set_Etype (Derived_Type, Parent_Base);
7565 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
7567 Set_Size_Info (Derived_Type, Parent_Type);
7568 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
7569 Set_Convention (Derived_Type, Convention (Parent_Type));
7570 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7571 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
7573 -- The derived type inherits the representation clauses of the parent.
7574 -- However, for a private type that is completed by a derivation, there
7575 -- may be operation attributes that have been specified already (stream
7576 -- attributes and External_Tag) and those must be provided. Finally,
7577 -- if the partial view is a private extension, the representation items
7578 -- of the parent have been inherited already, and should not be chained
7579 -- twice to the derived type.
7581 if Is_Tagged_Type (Parent_Type)
7582 and then Present (First_Rep_Item (Derived_Type))
7584 -- The existing items are either operational items or items inherited
7585 -- from a private extension declaration.
7589 -- Used to iterate over representation items of the derived type
7592 -- Last representation item of the (non-empty) representation
7593 -- item list of the derived type.
7595 Found : Boolean := False;
7598 Rep := First_Rep_Item (Derived_Type);
7600 while Present (Rep) loop
7601 if Rep = First_Rep_Item (Parent_Type) then
7606 Rep := Next_Rep_Item (Rep);
7608 if Present (Rep) then
7614 -- Here if we either encountered the parent type's first rep
7615 -- item on the derived type's rep item list (in which case
7616 -- Found is True, and we have nothing else to do), or if we
7617 -- reached the last rep item of the derived type, which is
7618 -- Last_Rep, in which case we further chain the parent type's
7619 -- rep items to those of the derived type.
7622 Set_Next_Rep_Item (Last_Rep, First_Rep_Item (Parent_Type));
7627 Set_First_Rep_Item (Derived_Type, First_Rep_Item (Parent_Type));
7630 case Ekind (Parent_Type) is
7631 when Numeric_Kind =>
7632 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
7635 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
7639 | Class_Wide_Kind =>
7640 Build_Derived_Record_Type
7641 (N, Parent_Type, Derived_Type, Derive_Subps);
7644 when Enumeration_Kind =>
7645 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
7648 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
7650 when Incomplete_Or_Private_Kind =>
7651 Build_Derived_Private_Type
7652 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
7654 -- For discriminated types, the derivation includes deriving
7655 -- primitive operations. For others it is done below.
7657 if Is_Tagged_Type (Parent_Type)
7658 or else Has_Discriminants (Parent_Type)
7659 or else (Present (Full_View (Parent_Type))
7660 and then Has_Discriminants (Full_View (Parent_Type)))
7665 when Concurrent_Kind =>
7666 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
7669 raise Program_Error;
7672 if Etype (Derived_Type) = Any_Type then
7676 -- Set delayed freeze and then derive subprograms, we need to do this
7677 -- in this order so that derived subprograms inherit the derived freeze
7680 Set_Has_Delayed_Freeze (Derived_Type);
7681 if Derive_Subps then
7682 Derive_Subprograms (Parent_Type, Derived_Type);
7685 Set_Has_Primitive_Operations
7686 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
7687 end Build_Derived_Type;
7689 -----------------------
7690 -- Build_Discriminal --
7691 -----------------------
7693 procedure Build_Discriminal (Discrim : Entity_Id) is
7694 D_Minal : Entity_Id;
7695 CR_Disc : Entity_Id;
7698 -- A discriminal has the same name as the discriminant
7701 Make_Defining_Identifier (Sloc (Discrim),
7702 Chars => Chars (Discrim));
7704 Set_Ekind (D_Minal, E_In_Parameter);
7705 Set_Mechanism (D_Minal, Default_Mechanism);
7706 Set_Etype (D_Minal, Etype (Discrim));
7708 Set_Discriminal (Discrim, D_Minal);
7709 Set_Discriminal_Link (D_Minal, Discrim);
7711 -- For task types, build at once the discriminants of the corresponding
7712 -- record, which are needed if discriminants are used in entry defaults
7713 -- and in family bounds.
7715 if Is_Concurrent_Type (Current_Scope)
7716 or else Is_Limited_Type (Current_Scope)
7718 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
7720 Set_Ekind (CR_Disc, E_In_Parameter);
7721 Set_Mechanism (CR_Disc, Default_Mechanism);
7722 Set_Etype (CR_Disc, Etype (Discrim));
7723 Set_Discriminal_Link (CR_Disc, Discrim);
7724 Set_CR_Discriminant (Discrim, CR_Disc);
7726 end Build_Discriminal;
7728 ------------------------------------
7729 -- Build_Discriminant_Constraints --
7730 ------------------------------------
7732 function Build_Discriminant_Constraints
7735 Derived_Def : Boolean := False) return Elist_Id
7737 C : constant Node_Id := Constraint (Def);
7738 Nb_Discr : constant Nat := Number_Discriminants (T);
7740 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
7741 -- Saves the expression corresponding to a given discriminant in T
7743 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
7744 -- Return the Position number within array Discr_Expr of a discriminant
7745 -- D within the discriminant list of the discriminated type T.
7751 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
7755 Disc := First_Discriminant (T);
7756 for J in Discr_Expr'Range loop
7761 Next_Discriminant (Disc);
7764 -- Note: Since this function is called on discriminants that are
7765 -- known to belong to the discriminated type, falling through the
7766 -- loop with no match signals an internal compiler error.
7768 raise Program_Error;
7771 -- Declarations local to Build_Discriminant_Constraints
7775 Elist : constant Elist_Id := New_Elmt_List;
7783 Discrim_Present : Boolean := False;
7785 -- Start of processing for Build_Discriminant_Constraints
7788 -- The following loop will process positional associations only.
7789 -- For a positional association, the (single) discriminant is
7790 -- implicitly specified by position, in textual order (RM 3.7.2).
7792 Discr := First_Discriminant (T);
7793 Constr := First (Constraints (C));
7794 for D in Discr_Expr'Range loop
7795 exit when Nkind (Constr) = N_Discriminant_Association;
7798 Error_Msg_N ("too few discriminants given in constraint", C);
7799 return New_Elmt_List;
7801 elsif Nkind (Constr) = N_Range
7802 or else (Nkind (Constr) = N_Attribute_Reference
7804 Attribute_Name (Constr) = Name_Range)
7807 ("a range is not a valid discriminant constraint", Constr);
7808 Discr_Expr (D) := Error;
7811 Analyze_And_Resolve (Constr, Base_Type (Etype (Discr)));
7812 Discr_Expr (D) := Constr;
7815 Next_Discriminant (Discr);
7819 if No (Discr) and then Present (Constr) then
7820 Error_Msg_N ("too many discriminants given in constraint", Constr);
7821 return New_Elmt_List;
7824 -- Named associations can be given in any order, but if both positional
7825 -- and named associations are used in the same discriminant constraint,
7826 -- then positional associations must occur first, at their normal
7827 -- position. Hence once a named association is used, the rest of the
7828 -- discriminant constraint must use only named associations.
7830 while Present (Constr) loop
7832 -- Positional association forbidden after a named association
7834 if Nkind (Constr) /= N_Discriminant_Association then
7835 Error_Msg_N ("positional association follows named one", Constr);
7836 return New_Elmt_List;
7838 -- Otherwise it is a named association
7841 -- E records the type of the discriminants in the named
7842 -- association. All the discriminants specified in the same name
7843 -- association must have the same type.
7847 -- Search the list of discriminants in T to see if the simple name
7848 -- given in the constraint matches any of them.
7850 Id := First (Selector_Names (Constr));
7851 while Present (Id) loop
7854 -- If Original_Discriminant is present, we are processing a
7855 -- generic instantiation and this is an instance node. We need
7856 -- to find the name of the corresponding discriminant in the
7857 -- actual record type T and not the name of the discriminant in
7858 -- the generic formal. Example:
7861 -- type G (D : int) is private;
7863 -- subtype W is G (D => 1);
7865 -- type Rec (X : int) is record ... end record;
7866 -- package Q is new P (G => Rec);
7868 -- At the point of the instantiation, formal type G is Rec
7869 -- and therefore when reanalyzing "subtype W is G (D => 1);"
7870 -- which really looks like "subtype W is Rec (D => 1);" at
7871 -- the point of instantiation, we want to find the discriminant
7872 -- that corresponds to D in Rec, i.e. X.
7874 if Present (Original_Discriminant (Id)) then
7875 Discr := Find_Corresponding_Discriminant (Id, T);
7879 Discr := First_Discriminant (T);
7880 while Present (Discr) loop
7881 if Chars (Discr) = Chars (Id) then
7886 Next_Discriminant (Discr);
7890 Error_Msg_N ("& does not match any discriminant", Id);
7891 return New_Elmt_List;
7893 -- The following is only useful for the benefit of generic
7894 -- instances but it does not interfere with other
7895 -- processing for the non-generic case so we do it in all
7896 -- cases (for generics this statement is executed when
7897 -- processing the generic definition, see comment at the
7898 -- beginning of this if statement).
7901 Set_Original_Discriminant (Id, Discr);
7905 Position := Pos_Of_Discr (T, Discr);
7907 if Present (Discr_Expr (Position)) then
7908 Error_Msg_N ("duplicate constraint for discriminant&", Id);
7911 -- Each discriminant specified in the same named association
7912 -- must be associated with a separate copy of the
7913 -- corresponding expression.
7915 if Present (Next (Id)) then
7916 Expr := New_Copy_Tree (Expression (Constr));
7917 Set_Parent (Expr, Parent (Expression (Constr)));
7919 Expr := Expression (Constr);
7922 Discr_Expr (Position) := Expr;
7923 Analyze_And_Resolve (Expr, Base_Type (Etype (Discr)));
7926 -- A discriminant association with more than one discriminant
7927 -- name is only allowed if the named discriminants are all of
7928 -- the same type (RM 3.7.1(8)).
7931 E := Base_Type (Etype (Discr));
7933 elsif Base_Type (Etype (Discr)) /= E then
7935 ("all discriminants in an association " &
7936 "must have the same type", Id);
7946 -- A discriminant constraint must provide exactly one value for each
7947 -- discriminant of the type (RM 3.7.1(8)).
7949 for J in Discr_Expr'Range loop
7950 if No (Discr_Expr (J)) then
7951 Error_Msg_N ("too few discriminants given in constraint", C);
7952 return New_Elmt_List;
7956 -- Determine if there are discriminant expressions in the constraint
7958 for J in Discr_Expr'Range loop
7959 if Denotes_Discriminant
7960 (Discr_Expr (J), Check_Concurrent => True)
7962 Discrim_Present := True;
7966 -- Build an element list consisting of the expressions given in the
7967 -- discriminant constraint and apply the appropriate checks. The list
7968 -- is constructed after resolving any named discriminant associations
7969 -- and therefore the expressions appear in the textual order of the
7972 Discr := First_Discriminant (T);
7973 for J in Discr_Expr'Range loop
7974 if Discr_Expr (J) /= Error then
7975 Append_Elmt (Discr_Expr (J), Elist);
7977 -- If any of the discriminant constraints is given by a
7978 -- discriminant and we are in a derived type declaration we
7979 -- have a discriminant renaming. Establish link between new
7980 -- and old discriminant.
7982 if Denotes_Discriminant (Discr_Expr (J)) then
7984 Set_Corresponding_Discriminant
7985 (Entity (Discr_Expr (J)), Discr);
7988 -- Force the evaluation of non-discriminant expressions.
7989 -- If we have found a discriminant in the constraint 3.4(26)
7990 -- and 3.8(18) demand that no range checks are performed are
7991 -- after evaluation. If the constraint is for a component
7992 -- definition that has a per-object constraint, expressions are
7993 -- evaluated but not checked either. In all other cases perform
7997 if Discrim_Present then
8000 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
8002 Has_Per_Object_Constraint
8003 (Defining_Identifier (Parent (Parent (Def))))
8007 elsif Is_Access_Type (Etype (Discr)) then
8008 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
8011 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
8014 Force_Evaluation (Discr_Expr (J));
8017 -- Check that the designated type of an access discriminant's
8018 -- expression is not a class-wide type unless the discriminant's
8019 -- designated type is also class-wide.
8021 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
8022 and then not Is_Class_Wide_Type
8023 (Designated_Type (Etype (Discr)))
8024 and then Etype (Discr_Expr (J)) /= Any_Type
8025 and then Is_Class_Wide_Type
8026 (Designated_Type (Etype (Discr_Expr (J))))
8028 Wrong_Type (Discr_Expr (J), Etype (Discr));
8030 elsif Is_Access_Type (Etype (Discr))
8031 and then not Is_Access_Constant (Etype (Discr))
8032 and then Is_Access_Type (Etype (Discr_Expr (J)))
8033 and then Is_Access_Constant (Etype (Discr_Expr (J)))
8036 ("constraint for discriminant& must be access to variable",
8041 Next_Discriminant (Discr);
8045 end Build_Discriminant_Constraints;
8047 ---------------------------------
8048 -- Build_Discriminated_Subtype --
8049 ---------------------------------
8051 procedure Build_Discriminated_Subtype
8055 Related_Nod : Node_Id;
8056 For_Access : Boolean := False)
8058 Has_Discrs : constant Boolean := Has_Discriminants (T);
8059 Constrained : constant Boolean :=
8061 and then not Is_Empty_Elmt_List (Elist)
8062 and then not Is_Class_Wide_Type (T))
8063 or else Is_Constrained (T);
8066 if Ekind (T) = E_Record_Type then
8068 Set_Ekind (Def_Id, E_Private_Subtype);
8069 Set_Is_For_Access_Subtype (Def_Id, True);
8071 Set_Ekind (Def_Id, E_Record_Subtype);
8074 -- Inherit preelaboration flag from base, for types for which it
8075 -- may have been set: records, private types, protected types.
8077 Set_Known_To_Have_Preelab_Init
8078 (Def_Id, Known_To_Have_Preelab_Init (T));
8080 elsif Ekind (T) = E_Task_Type then
8081 Set_Ekind (Def_Id, E_Task_Subtype);
8083 elsif Ekind (T) = E_Protected_Type then
8084 Set_Ekind (Def_Id, E_Protected_Subtype);
8085 Set_Known_To_Have_Preelab_Init
8086 (Def_Id, Known_To_Have_Preelab_Init (T));
8088 elsif Is_Private_Type (T) then
8089 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
8090 Set_Known_To_Have_Preelab_Init
8091 (Def_Id, Known_To_Have_Preelab_Init (T));
8093 elsif Is_Class_Wide_Type (T) then
8094 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
8097 -- Incomplete type. Attach subtype to list of dependents, to be
8098 -- completed with full view of parent type, unless is it the
8099 -- designated subtype of a record component within an init_proc.
8100 -- This last case arises for a component of an access type whose
8101 -- designated type is incomplete (e.g. a Taft Amendment type).
8102 -- The designated subtype is within an inner scope, and needs no
8103 -- elaboration, because only the access type is needed in the
8104 -- initialization procedure.
8106 Set_Ekind (Def_Id, Ekind (T));
8108 if For_Access and then Within_Init_Proc then
8111 Append_Elmt (Def_Id, Private_Dependents (T));
8115 Set_Etype (Def_Id, T);
8116 Init_Size_Align (Def_Id);
8117 Set_Has_Discriminants (Def_Id, Has_Discrs);
8118 Set_Is_Constrained (Def_Id, Constrained);
8120 Set_First_Entity (Def_Id, First_Entity (T));
8121 Set_Last_Entity (Def_Id, Last_Entity (T));
8123 -- If the subtype is the completion of a private declaration, there may
8124 -- have been representation clauses for the partial view, and they must
8125 -- be preserved. Build_Derived_Type chains the inherited clauses with
8126 -- the ones appearing on the extension. If this comes from a subtype
8127 -- declaration, all clauses are inherited.
8129 if No (First_Rep_Item (Def_Id)) then
8130 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
8133 if Is_Tagged_Type (T) then
8134 Set_Is_Tagged_Type (Def_Id);
8135 Make_Class_Wide_Type (Def_Id);
8138 Set_Stored_Constraint (Def_Id, No_Elist);
8141 Set_Discriminant_Constraint (Def_Id, Elist);
8142 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
8145 if Is_Tagged_Type (T) then
8147 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
8148 -- concurrent record type (which has the list of primitive
8151 if Ada_Version >= Ada_05
8152 and then Is_Concurrent_Type (T)
8154 Set_Corresponding_Record_Type (Def_Id,
8155 Corresponding_Record_Type (T));
8157 Set_Primitive_Operations (Def_Id, Primitive_Operations (T));
8160 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
8163 -- Subtypes introduced by component declarations do not need to be
8164 -- marked as delayed, and do not get freeze nodes, because the semantics
8165 -- verifies that the parents of the subtypes are frozen before the
8166 -- enclosing record is frozen.
8168 if not Is_Type (Scope (Def_Id)) then
8169 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
8171 if Is_Private_Type (T)
8172 and then Present (Full_View (T))
8174 Conditional_Delay (Def_Id, Full_View (T));
8176 Conditional_Delay (Def_Id, T);
8180 if Is_Record_Type (T) then
8181 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
8184 and then not Is_Empty_Elmt_List (Elist)
8185 and then not For_Access
8187 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
8188 elsif not For_Access then
8189 Set_Cloned_Subtype (Def_Id, T);
8192 end Build_Discriminated_Subtype;
8194 ---------------------------
8195 -- Build_Itype_Reference --
8196 ---------------------------
8198 procedure Build_Itype_Reference
8202 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
8204 Set_Itype (IR, Ityp);
8205 Insert_After (Nod, IR);
8206 end Build_Itype_Reference;
8208 ------------------------
8209 -- Build_Scalar_Bound --
8210 ------------------------
8212 function Build_Scalar_Bound
8215 Der_T : Entity_Id) return Node_Id
8217 New_Bound : Entity_Id;
8220 -- Note: not clear why this is needed, how can the original bound
8221 -- be unanalyzed at this point? and if it is, what business do we
8222 -- have messing around with it? and why is the base type of the
8223 -- parent type the right type for the resolution. It probably is
8224 -- not! It is OK for the new bound we are creating, but not for
8225 -- the old one??? Still if it never happens, no problem!
8227 Analyze_And_Resolve (Bound, Base_Type (Par_T));
8229 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
8230 New_Bound := New_Copy (Bound);
8231 Set_Etype (New_Bound, Der_T);
8232 Set_Analyzed (New_Bound);
8234 elsif Is_Entity_Name (Bound) then
8235 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
8237 -- The following is almost certainly wrong. What business do we have
8238 -- relocating a node (Bound) that is presumably still attached to
8239 -- the tree elsewhere???
8242 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
8245 Set_Etype (New_Bound, Der_T);
8247 end Build_Scalar_Bound;
8249 --------------------------------
8250 -- Build_Underlying_Full_View --
8251 --------------------------------
8253 procedure Build_Underlying_Full_View
8258 Loc : constant Source_Ptr := Sloc (N);
8259 Subt : constant Entity_Id :=
8260 Make_Defining_Identifier
8261 (Loc, New_External_Name (Chars (Typ), 'S'));
8268 procedure Set_Discriminant_Name (Id : Node_Id);
8269 -- If the derived type has discriminants, they may rename discriminants
8270 -- of the parent. When building the full view of the parent, we need to
8271 -- recover the names of the original discriminants if the constraint is
8272 -- given by named associations.
8274 ---------------------------
8275 -- Set_Discriminant_Name --
8276 ---------------------------
8278 procedure Set_Discriminant_Name (Id : Node_Id) is
8282 Set_Original_Discriminant (Id, Empty);
8284 if Has_Discriminants (Typ) then
8285 Disc := First_Discriminant (Typ);
8286 while Present (Disc) loop
8287 if Chars (Disc) = Chars (Id)
8288 and then Present (Corresponding_Discriminant (Disc))
8290 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
8292 Next_Discriminant (Disc);
8295 end Set_Discriminant_Name;
8297 -- Start of processing for Build_Underlying_Full_View
8300 if Nkind (N) = N_Full_Type_Declaration then
8301 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
8303 elsif Nkind (N) = N_Subtype_Declaration then
8304 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
8306 elsif Nkind (N) = N_Component_Declaration then
8309 (Constraint (Subtype_Indication (Component_Definition (N))));
8312 raise Program_Error;
8315 C := First (Constraints (Constr));
8316 while Present (C) loop
8317 if Nkind (C) = N_Discriminant_Association then
8318 Id := First (Selector_Names (C));
8319 while Present (Id) loop
8320 Set_Discriminant_Name (Id);
8329 Make_Subtype_Declaration (Loc,
8330 Defining_Identifier => Subt,
8331 Subtype_Indication =>
8332 Make_Subtype_Indication (Loc,
8333 Subtype_Mark => New_Reference_To (Par, Loc),
8334 Constraint => New_Copy_Tree (Constr)));
8336 -- If this is a component subtype for an outer itype, it is not
8337 -- a list member, so simply set the parent link for analysis: if
8338 -- the enclosing type does not need to be in a declarative list,
8339 -- neither do the components.
8341 if Is_List_Member (N)
8342 and then Nkind (N) /= N_Component_Declaration
8344 Insert_Before (N, Indic);
8346 Set_Parent (Indic, Parent (N));
8350 Set_Underlying_Full_View (Typ, Full_View (Subt));
8351 end Build_Underlying_Full_View;
8353 -------------------------------
8354 -- Check_Abstract_Overriding --
8355 -------------------------------
8357 procedure Check_Abstract_Overriding (T : Entity_Id) is
8358 Alias_Subp : Entity_Id;
8365 Op_List := Primitive_Operations (T);
8367 -- Loop to check primitive operations
8369 Elmt := First_Elmt (Op_List);
8370 while Present (Elmt) loop
8371 Subp := Node (Elmt);
8372 Alias_Subp := Alias (Subp);
8374 -- Inherited subprograms are identified by the fact that they do not
8375 -- come from source, and the associated source location is the
8376 -- location of the first subtype of the derived type.
8378 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
8379 -- subprograms that "require overriding".
8381 -- Special exception, do not complain about failure to override the
8382 -- stream routines _Input and _Output, as well as the primitive
8383 -- operations used in dispatching selects since we always provide
8384 -- automatic overridings for these subprograms.
8386 -- Also ignore this rule for convention CIL since .NET libraries
8387 -- do bizarre things with interfaces???
8389 -- The partial view of T may have been a private extension, for
8390 -- which inherited functions dispatching on result are abstract.
8391 -- If the full view is a null extension, there is no need for
8392 -- overriding in Ada2005, but wrappers need to be built for them
8393 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
8395 if Is_Null_Extension (T)
8396 and then Has_Controlling_Result (Subp)
8397 and then Ada_Version >= Ada_05
8398 and then Present (Alias_Subp)
8399 and then not Comes_From_Source (Subp)
8400 and then not Is_Abstract_Subprogram (Alias_Subp)
8401 and then not Is_Access_Type (Etype (Subp))
8405 -- Ada 2005 (AI-251): Internal entities of interfaces need no
8406 -- processing because this check is done with the aliased
8409 elsif Present (Interface_Alias (Subp)) then
8412 elsif (Is_Abstract_Subprogram (Subp)
8413 or else Requires_Overriding (Subp)
8415 (Has_Controlling_Result (Subp)
8416 and then Present (Alias_Subp)
8417 and then not Comes_From_Source (Subp)
8418 and then Sloc (Subp) = Sloc (First_Subtype (T))))
8419 and then not Is_TSS (Subp, TSS_Stream_Input)
8420 and then not Is_TSS (Subp, TSS_Stream_Output)
8421 and then not Is_Abstract_Type (T)
8422 and then Convention (T) /= Convention_CIL
8423 and then not Is_Predefined_Interface_Primitive (Subp)
8425 -- Ada 2005 (AI-251): Do not consider hidden entities associated
8426 -- with abstract interface types because the check will be done
8427 -- with the aliased entity (otherwise we generate a duplicated
8430 and then not Present (Interface_Alias (Subp))
8432 if Present (Alias_Subp) then
8434 -- Only perform the check for a derived subprogram when the
8435 -- type has an explicit record extension. This avoids incorrect
8436 -- flagging of abstract subprograms for the case of a type
8437 -- without an extension that is derived from a formal type
8438 -- with a tagged actual (can occur within a private part).
8440 -- Ada 2005 (AI-391): In the case of an inherited function with
8441 -- a controlling result of the type, the rule does not apply if
8442 -- the type is a null extension (unless the parent function
8443 -- itself is abstract, in which case the function must still be
8444 -- be overridden). The expander will generate an overriding
8445 -- wrapper function calling the parent subprogram (see
8446 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
8448 Type_Def := Type_Definition (Parent (T));
8450 if Nkind (Type_Def) = N_Derived_Type_Definition
8451 and then Present (Record_Extension_Part (Type_Def))
8453 (Ada_Version < Ada_05
8454 or else not Is_Null_Extension (T)
8455 or else Ekind (Subp) = E_Procedure
8456 or else not Has_Controlling_Result (Subp)
8457 or else Is_Abstract_Subprogram (Alias_Subp)
8458 or else Requires_Overriding (Subp)
8459 or else Is_Access_Type (Etype (Subp)))
8461 -- Avoid reporting error in case of abstract predefined
8462 -- primitive inherited from interface type because the
8463 -- body of internally generated predefined primitives
8464 -- of tagged types are generated later by Freeze_Type
8466 if Is_Interface (Root_Type (T))
8467 and then Is_Abstract_Subprogram (Subp)
8468 and then Is_Predefined_Dispatching_Operation (Subp)
8469 and then not Comes_From_Source (Ultimate_Alias (Subp))
8475 ("type must be declared abstract or & overridden",
8478 -- Traverse the whole chain of aliased subprograms to
8479 -- complete the error notification. This is especially
8480 -- useful for traceability of the chain of entities when
8481 -- the subprogram corresponds with an interface
8482 -- subprogram (which may be defined in another package).
8484 if Present (Alias_Subp) then
8490 while Present (Alias (E)) loop
8491 Error_Msg_Sloc := Sloc (E);
8493 ("\& has been inherited #", T, Subp);
8497 Error_Msg_Sloc := Sloc (E);
8499 ("\& has been inherited from subprogram #",
8505 -- Ada 2005 (AI-345): Protected or task type implementing
8506 -- abstract interfaces.
8508 elsif Is_Concurrent_Record_Type (T)
8509 and then Present (Interfaces (T))
8511 -- The controlling formal of Subp must be of mode "out",
8512 -- "in out" or an access-to-variable to be overridden.
8514 -- Error message below needs rewording (remember comma
8515 -- in -gnatj mode) ???
8517 if Ekind (First_Formal (Subp)) = E_In_Parameter
8518 and then Ekind (Subp) /= E_Function
8520 if not Is_Predefined_Dispatching_Operation (Subp) then
8522 ("first formal of & must be of mode `OUT`, " &
8523 "`IN OUT` or access-to-variable", T, Subp);
8525 ("\to be overridden by protected procedure or " &
8526 "entry (RM 9.4(11.9/2))", T);
8529 -- Some other kind of overriding failure
8533 ("interface subprogram & must be overridden",
8536 -- Examine primitive operations of synchronized type,
8537 -- to find homonyms that have the wrong profile.
8544 First_Entity (Corresponding_Concurrent_Type (T));
8545 while Present (Prim) loop
8546 if Chars (Prim) = Chars (Subp) then
8548 ("profile is not type conformant with "
8549 & "prefixed view profile of "
8550 & "inherited operation&", Prim, Subp);
8560 Error_Msg_Node_2 := T;
8562 ("abstract subprogram& not allowed for type&", Subp);
8564 -- Also post unconditional warning on the type (unconditional
8565 -- so that if there are more than one of these cases, we get
8566 -- them all, and not just the first one).
8568 Error_Msg_Node_2 := Subp;
8570 ("nonabstract type& has abstract subprogram&!", T);
8574 -- Ada 2005 (AI05-0030): Inspect hidden subprograms which provide
8575 -- the mapping between interface and implementing type primitives.
8576 -- If the interface alias is marked as Implemented_By_Entry, the
8577 -- alias must be an entry wrapper.
8579 if Ada_Version >= Ada_05
8580 and then Is_Hidden (Subp)
8581 and then Present (Interface_Alias (Subp))
8582 and then Implemented_By_Entry (Interface_Alias (Subp))
8583 and then Present (Alias_Subp)
8585 (not Is_Primitive_Wrapper (Alias_Subp)
8586 or else Ekind (Wrapped_Entity (Alias_Subp)) /= E_Entry)
8589 Error_Ent : Entity_Id := T;
8592 if Is_Concurrent_Record_Type (Error_Ent) then
8593 Error_Ent := Corresponding_Concurrent_Type (Error_Ent);
8596 Error_Msg_Node_2 := Interface_Alias (Subp);
8598 ("type & must implement abstract subprogram & with an entry",
8599 Error_Ent, Error_Ent);
8605 end Check_Abstract_Overriding;
8607 ------------------------------------------------
8608 -- Check_Access_Discriminant_Requires_Limited --
8609 ------------------------------------------------
8611 procedure Check_Access_Discriminant_Requires_Limited
8616 -- A discriminant_specification for an access discriminant shall appear
8617 -- only in the declaration for a task or protected type, or for a type
8618 -- with the reserved word 'limited' in its definition or in one of its
8619 -- ancestors. (RM 3.7(10))
8621 if Nkind (Discriminant_Type (D)) = N_Access_Definition
8622 and then not Is_Concurrent_Type (Current_Scope)
8623 and then not Is_Concurrent_Record_Type (Current_Scope)
8624 and then not Is_Limited_Record (Current_Scope)
8625 and then Ekind (Current_Scope) /= E_Limited_Private_Type
8628 ("access discriminants allowed only for limited types", Loc);
8630 end Check_Access_Discriminant_Requires_Limited;
8632 -----------------------------------
8633 -- Check_Aliased_Component_Types --
8634 -----------------------------------
8636 procedure Check_Aliased_Component_Types (T : Entity_Id) is
8640 -- ??? Also need to check components of record extensions, but not
8641 -- components of protected types (which are always limited).
8643 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
8644 -- types to be unconstrained. This is safe because it is illegal to
8645 -- create access subtypes to such types with explicit discriminant
8648 if not Is_Limited_Type (T) then
8649 if Ekind (T) = E_Record_Type then
8650 C := First_Component (T);
8651 while Present (C) loop
8653 and then Has_Discriminants (Etype (C))
8654 and then not Is_Constrained (Etype (C))
8655 and then not In_Instance_Body
8656 and then Ada_Version < Ada_05
8659 ("aliased component must be constrained (RM 3.6(11))",
8666 elsif Ekind (T) = E_Array_Type then
8667 if Has_Aliased_Components (T)
8668 and then Has_Discriminants (Component_Type (T))
8669 and then not Is_Constrained (Component_Type (T))
8670 and then not In_Instance_Body
8671 and then Ada_Version < Ada_05
8674 ("aliased component type must be constrained (RM 3.6(11))",
8679 end Check_Aliased_Component_Types;
8681 ----------------------
8682 -- Check_Completion --
8683 ----------------------
8685 procedure Check_Completion (Body_Id : Node_Id := Empty) is
8688 procedure Post_Error;
8689 -- Post error message for lack of completion for entity E
8695 procedure Post_Error is
8697 procedure Missing_Body;
8698 -- Output missing body message
8704 procedure Missing_Body is
8706 -- Spec is in same unit, so we can post on spec
8708 if In_Same_Source_Unit (Body_Id, E) then
8709 Error_Msg_N ("missing body for &", E);
8711 -- Spec is in a separate unit, so we have to post on the body
8714 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
8718 -- Start of processing for Post_Error
8721 if not Comes_From_Source (E) then
8723 if Ekind (E) = E_Task_Type
8724 or else Ekind (E) = E_Protected_Type
8726 -- It may be an anonymous protected type created for a
8727 -- single variable. Post error on variable, if present.
8733 Var := First_Entity (Current_Scope);
8734 while Present (Var) loop
8735 exit when Etype (Var) = E
8736 and then Comes_From_Source (Var);
8741 if Present (Var) then
8748 -- If a generated entity has no completion, then either previous
8749 -- semantic errors have disabled the expansion phase, or else we had
8750 -- missing subunits, or else we are compiling without expansion,
8751 -- or else something is very wrong.
8753 if not Comes_From_Source (E) then
8755 (Serious_Errors_Detected > 0
8756 or else Configurable_Run_Time_Violations > 0
8757 or else Subunits_Missing
8758 or else not Expander_Active);
8761 -- Here for source entity
8764 -- Here if no body to post the error message, so we post the error
8765 -- on the declaration that has no completion. This is not really
8766 -- the right place to post it, think about this later ???
8768 if No (Body_Id) then
8771 ("missing full declaration for }", Parent (E), E);
8774 ("missing body for &", Parent (E), E);
8777 -- Package body has no completion for a declaration that appears
8778 -- in the corresponding spec. Post error on the body, with a
8779 -- reference to the non-completed declaration.
8782 Error_Msg_Sloc := Sloc (E);
8786 ("missing full declaration for }!", Body_Id, E);
8788 elsif Is_Overloadable (E)
8789 and then Current_Entity_In_Scope (E) /= E
8791 -- It may be that the completion is mistyped and appears as
8792 -- a distinct overloading of the entity.
8795 Candidate : constant Entity_Id :=
8796 Current_Entity_In_Scope (E);
8797 Decl : constant Node_Id :=
8798 Unit_Declaration_Node (Candidate);
8801 if Is_Overloadable (Candidate)
8802 and then Ekind (Candidate) = Ekind (E)
8803 and then Nkind (Decl) = N_Subprogram_Body
8804 and then Acts_As_Spec (Decl)
8806 Check_Type_Conformant (Candidate, E);
8820 -- Start of processing for Check_Completion
8823 E := First_Entity (Current_Scope);
8824 while Present (E) loop
8825 if Is_Intrinsic_Subprogram (E) then
8828 -- The following situation requires special handling: a child unit
8829 -- that appears in the context clause of the body of its parent:
8831 -- procedure Parent.Child (...);
8833 -- with Parent.Child;
8834 -- package body Parent is
8836 -- Here Parent.Child appears as a local entity, but should not be
8837 -- flagged as requiring completion, because it is a compilation
8840 -- Ignore missing completion for a subprogram that does not come from
8841 -- source (including the _Call primitive operation of RAS types,
8842 -- which has to have the flag Comes_From_Source for other purposes):
8843 -- we assume that the expander will provide the missing completion.
8844 -- In case of previous errors, other expansion actions that provide
8845 -- bodies for null procedures with not be invoked, so inhibit message
8847 -- Note that E_Operator is not in the list that follows, because
8848 -- this kind is reserved for predefined operators, that are
8849 -- intrinsic and do not need completion.
8851 elsif Ekind (E) = E_Function
8852 or else Ekind (E) = E_Procedure
8853 or else Ekind (E) = E_Generic_Function
8854 or else Ekind (E) = E_Generic_Procedure
8856 if Has_Completion (E) then
8859 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
8862 elsif Is_Subprogram (E)
8863 and then (not Comes_From_Source (E)
8864 or else Chars (E) = Name_uCall)
8869 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
8873 elsif Nkind (Parent (E)) = N_Procedure_Specification
8874 and then Null_Present (Parent (E))
8875 and then Serious_Errors_Detected > 0
8883 elsif Is_Entry (E) then
8884 if not Has_Completion (E) and then
8885 (Ekind (Scope (E)) = E_Protected_Object
8886 or else Ekind (Scope (E)) = E_Protected_Type)
8891 elsif Is_Package_Or_Generic_Package (E) then
8892 if Unit_Requires_Body (E) then
8893 if not Has_Completion (E)
8894 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
8900 elsif not Is_Child_Unit (E) then
8901 May_Need_Implicit_Body (E);
8904 elsif Ekind (E) = E_Incomplete_Type
8905 and then No (Underlying_Type (E))
8909 elsif (Ekind (E) = E_Task_Type or else
8910 Ekind (E) = E_Protected_Type)
8911 and then not Has_Completion (E)
8915 -- A single task declared in the current scope is a constant, verify
8916 -- that the body of its anonymous type is in the same scope. If the
8917 -- task is defined elsewhere, this may be a renaming declaration for
8918 -- which no completion is needed.
8920 elsif Ekind (E) = E_Constant
8921 and then Ekind (Etype (E)) = E_Task_Type
8922 and then not Has_Completion (Etype (E))
8923 and then Scope (Etype (E)) = Current_Scope
8927 elsif Ekind (E) = E_Protected_Object
8928 and then not Has_Completion (Etype (E))
8932 elsif Ekind (E) = E_Record_Type then
8933 if Is_Tagged_Type (E) then
8934 Check_Abstract_Overriding (E);
8935 Check_Conventions (E);
8938 Check_Aliased_Component_Types (E);
8940 elsif Ekind (E) = E_Array_Type then
8941 Check_Aliased_Component_Types (E);
8947 end Check_Completion;
8949 ----------------------------
8950 -- Check_Delta_Expression --
8951 ----------------------------
8953 procedure Check_Delta_Expression (E : Node_Id) is
8955 if not (Is_Real_Type (Etype (E))) then
8956 Wrong_Type (E, Any_Real);
8958 elsif not Is_OK_Static_Expression (E) then
8959 Flag_Non_Static_Expr
8960 ("non-static expression used for delta value!", E);
8962 elsif not UR_Is_Positive (Expr_Value_R (E)) then
8963 Error_Msg_N ("delta expression must be positive", E);
8969 -- If any of above errors occurred, then replace the incorrect
8970 -- expression by the real 0.1, which should prevent further errors.
8973 Make_Real_Literal (Sloc (E), Ureal_Tenth));
8974 Analyze_And_Resolve (E, Standard_Float);
8975 end Check_Delta_Expression;
8977 -----------------------------
8978 -- Check_Digits_Expression --
8979 -----------------------------
8981 procedure Check_Digits_Expression (E : Node_Id) is
8983 if not (Is_Integer_Type (Etype (E))) then
8984 Wrong_Type (E, Any_Integer);
8986 elsif not Is_OK_Static_Expression (E) then
8987 Flag_Non_Static_Expr
8988 ("non-static expression used for digits value!", E);
8990 elsif Expr_Value (E) <= 0 then
8991 Error_Msg_N ("digits value must be greater than zero", E);
8997 -- If any of above errors occurred, then replace the incorrect
8998 -- expression by the integer 1, which should prevent further errors.
9000 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
9001 Analyze_And_Resolve (E, Standard_Integer);
9003 end Check_Digits_Expression;
9005 --------------------------
9006 -- Check_Initialization --
9007 --------------------------
9009 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
9011 if Is_Limited_Type (T)
9012 and then not In_Instance
9013 and then not In_Inlined_Body
9015 if not OK_For_Limited_Init (T, Exp) then
9017 -- In GNAT mode, this is just a warning, to allow it to be evilly
9018 -- turned off. Otherwise it is a real error.
9022 ("?cannot initialize entities of limited type!", Exp);
9024 elsif Ada_Version < Ada_05 then
9026 ("cannot initialize entities of limited type", Exp);
9027 Explain_Limited_Type (T, Exp);
9030 -- Specialize error message according to kind of illegal
9031 -- initial expression.
9033 if Nkind (Exp) = N_Type_Conversion
9034 and then Nkind (Expression (Exp)) = N_Function_Call
9037 ("illegal context for call"
9038 & " to function with limited result", Exp);
9042 ("initialization of limited object requires aggregate "
9043 & "or function call", Exp);
9048 end Check_Initialization;
9050 ----------------------
9051 -- Check_Interfaces --
9052 ----------------------
9054 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
9055 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
9058 Iface_Def : Node_Id;
9059 Iface_Typ : Entity_Id;
9060 Parent_Node : Node_Id;
9062 Is_Task : Boolean := False;
9063 -- Set True if parent type or any progenitor is a task interface
9065 Is_Protected : Boolean := False;
9066 -- Set True if parent type or any progenitor is a protected interface
9068 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
9069 -- Check that a progenitor is compatible with declaration.
9070 -- Error is posted on Error_Node.
9076 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
9077 Iface_Id : constant Entity_Id :=
9078 Defining_Identifier (Parent (Iface_Def));
9082 if Nkind (N) = N_Private_Extension_Declaration then
9085 Type_Def := Type_Definition (N);
9088 if Is_Task_Interface (Iface_Id) then
9091 elsif Is_Protected_Interface (Iface_Id) then
9092 Is_Protected := True;
9095 if Is_Synchronized_Interface (Iface_Id) then
9097 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
9098 -- extension derived from a synchronized interface must explicitly
9099 -- be declared synchronized, because the full view will be a
9100 -- synchronized type.
9102 if Nkind (N) = N_Private_Extension_Declaration then
9103 if not Synchronized_Present (N) then
9105 ("private extension of& must be explicitly synchronized",
9109 -- However, by 3.9.4(16/2), a full type that is a record extension
9110 -- is never allowed to derive from a synchronized interface (note
9111 -- that interfaces must be excluded from this check, because those
9112 -- are represented by derived type definitions in some cases).
9114 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9115 and then not Interface_Present (Type_Definition (N))
9117 Error_Msg_N ("record extension cannot derive from synchronized"
9118 & " interface", Error_Node);
9122 -- Check that the characteristics of the progenitor are compatible
9123 -- with the explicit qualifier in the declaration.
9124 -- The check only applies to qualifiers that come from source.
9125 -- Limited_Present also appears in the declaration of corresponding
9126 -- records, and the check does not apply to them.
9128 if Limited_Present (Type_Def)
9130 Is_Concurrent_Record_Type (Defining_Identifier (N))
9132 if Is_Limited_Interface (Parent_Type)
9133 and then not Is_Limited_Interface (Iface_Id)
9136 ("progenitor& must be limited interface",
9137 Error_Node, Iface_Id);
9140 (Task_Present (Iface_Def)
9141 or else Protected_Present (Iface_Def)
9142 or else Synchronized_Present (Iface_Def))
9143 and then Nkind (N) /= N_Private_Extension_Declaration
9144 and then not Error_Posted (N)
9147 ("progenitor& must be limited interface",
9148 Error_Node, Iface_Id);
9151 -- Protected interfaces can only inherit from limited, synchronized
9152 -- or protected interfaces.
9154 elsif Nkind (N) = N_Full_Type_Declaration
9155 and then Protected_Present (Type_Def)
9157 if Limited_Present (Iface_Def)
9158 or else Synchronized_Present (Iface_Def)
9159 or else Protected_Present (Iface_Def)
9163 elsif Task_Present (Iface_Def) then
9164 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9165 & " from task interface", Error_Node);
9168 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9169 & " from non-limited interface", Error_Node);
9172 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
9173 -- limited and synchronized.
9175 elsif Synchronized_Present (Type_Def) then
9176 if Limited_Present (Iface_Def)
9177 or else Synchronized_Present (Iface_Def)
9181 elsif Protected_Present (Iface_Def)
9182 and then Nkind (N) /= N_Private_Extension_Declaration
9184 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9185 & " from protected interface", Error_Node);
9187 elsif Task_Present (Iface_Def)
9188 and then Nkind (N) /= N_Private_Extension_Declaration
9190 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9191 & " from task interface", Error_Node);
9193 elsif not Is_Limited_Interface (Iface_Id) then
9194 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9195 & " from non-limited interface", Error_Node);
9198 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
9199 -- synchronized or task interfaces.
9201 elsif Nkind (N) = N_Full_Type_Declaration
9202 and then Task_Present (Type_Def)
9204 if Limited_Present (Iface_Def)
9205 or else Synchronized_Present (Iface_Def)
9206 or else Task_Present (Iface_Def)
9210 elsif Protected_Present (Iface_Def) then
9211 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9212 & " protected interface", Error_Node);
9215 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9216 & " non-limited interface", Error_Node);
9221 -- Start of processing for Check_Interfaces
9224 if Is_Interface (Parent_Type) then
9225 if Is_Task_Interface (Parent_Type) then
9228 elsif Is_Protected_Interface (Parent_Type) then
9229 Is_Protected := True;
9233 if Nkind (N) = N_Private_Extension_Declaration then
9235 -- Check that progenitors are compatible with declaration
9237 Iface := First (Interface_List (Def));
9238 while Present (Iface) loop
9239 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9241 Parent_Node := Parent (Base_Type (Iface_Typ));
9242 Iface_Def := Type_Definition (Parent_Node);
9244 if not Is_Interface (Iface_Typ) then
9245 Diagnose_Interface (Iface, Iface_Typ);
9248 Check_Ifaces (Iface_Def, Iface);
9254 if Is_Task and Is_Protected then
9256 ("type cannot derive from task and protected interface", N);
9262 -- Full type declaration of derived type.
9263 -- Check compatibility with parent if it is interface type
9265 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9266 and then Is_Interface (Parent_Type)
9268 Parent_Node := Parent (Parent_Type);
9270 -- More detailed checks for interface varieties
9273 (Iface_Def => Type_Definition (Parent_Node),
9274 Error_Node => Subtype_Indication (Type_Definition (N)));
9277 Iface := First (Interface_List (Def));
9278 while Present (Iface) loop
9279 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9281 Parent_Node := Parent (Base_Type (Iface_Typ));
9282 Iface_Def := Type_Definition (Parent_Node);
9284 if not Is_Interface (Iface_Typ) then
9285 Diagnose_Interface (Iface, Iface_Typ);
9288 -- "The declaration of a specific descendant of an interface
9289 -- type freezes the interface type" RM 13.14
9291 Freeze_Before (N, Iface_Typ);
9292 Check_Ifaces (Iface_Def, Error_Node => Iface);
9298 if Is_Task and Is_Protected then
9300 ("type cannot derive from task and protected interface", N);
9302 end Check_Interfaces;
9304 ------------------------------------
9305 -- Check_Or_Process_Discriminants --
9306 ------------------------------------
9308 -- If an incomplete or private type declaration was already given for the
9309 -- type, the discriminants may have already been processed if they were
9310 -- present on the incomplete declaration. In this case a full conformance
9311 -- check is performed otherwise just process them.
9313 procedure Check_Or_Process_Discriminants
9316 Prev : Entity_Id := Empty)
9319 if Has_Discriminants (T) then
9321 -- Make the discriminants visible to component declarations
9328 D := First_Discriminant (T);
9329 while Present (D) loop
9330 Prev := Current_Entity (D);
9331 Set_Current_Entity (D);
9332 Set_Is_Immediately_Visible (D);
9333 Set_Homonym (D, Prev);
9335 -- Ada 2005 (AI-230): Access discriminant allowed in
9336 -- non-limited record types.
9338 if Ada_Version < Ada_05 then
9340 -- This restriction gets applied to the full type here. It
9341 -- has already been applied earlier to the partial view.
9343 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
9346 Next_Discriminant (D);
9350 elsif Present (Discriminant_Specifications (N)) then
9351 Process_Discriminants (N, Prev);
9353 end Check_Or_Process_Discriminants;
9355 ----------------------
9356 -- Check_Real_Bound --
9357 ----------------------
9359 procedure Check_Real_Bound (Bound : Node_Id) is
9361 if not Is_Real_Type (Etype (Bound)) then
9363 ("bound in real type definition must be of real type", Bound);
9365 elsif not Is_OK_Static_Expression (Bound) then
9366 Flag_Non_Static_Expr
9367 ("non-static expression used for real type bound!", Bound);
9374 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
9376 Resolve (Bound, Standard_Float);
9377 end Check_Real_Bound;
9379 ------------------------------
9380 -- Complete_Private_Subtype --
9381 ------------------------------
9383 procedure Complete_Private_Subtype
9386 Full_Base : Entity_Id;
9387 Related_Nod : Node_Id)
9389 Save_Next_Entity : Entity_Id;
9390 Save_Homonym : Entity_Id;
9393 -- Set semantic attributes for (implicit) private subtype completion.
9394 -- If the full type has no discriminants, then it is a copy of the full
9395 -- view of the base. Otherwise, it is a subtype of the base with a
9396 -- possible discriminant constraint. Save and restore the original
9397 -- Next_Entity field of full to ensure that the calls to Copy_Node
9398 -- do not corrupt the entity chain.
9400 -- Note that the type of the full view is the same entity as the type of
9401 -- the partial view. In this fashion, the subtype has access to the
9402 -- correct view of the parent.
9404 Save_Next_Entity := Next_Entity (Full);
9405 Save_Homonym := Homonym (Priv);
9407 case Ekind (Full_Base) is
9408 when E_Record_Type |
9414 Copy_Node (Priv, Full);
9416 Set_Has_Discriminants (Full, Has_Discriminants (Full_Base));
9417 Set_First_Entity (Full, First_Entity (Full_Base));
9418 Set_Last_Entity (Full, Last_Entity (Full_Base));
9421 Copy_Node (Full_Base, Full);
9422 Set_Chars (Full, Chars (Priv));
9423 Conditional_Delay (Full, Priv);
9424 Set_Sloc (Full, Sloc (Priv));
9427 Set_Next_Entity (Full, Save_Next_Entity);
9428 Set_Homonym (Full, Save_Homonym);
9429 Set_Associated_Node_For_Itype (Full, Related_Nod);
9431 -- Set common attributes for all subtypes
9433 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
9435 -- The Etype of the full view is inconsistent. Gigi needs to see the
9436 -- structural full view, which is what the current scheme gives:
9437 -- the Etype of the full view is the etype of the full base. However,
9438 -- if the full base is a derived type, the full view then looks like
9439 -- a subtype of the parent, not a subtype of the full base. If instead
9442 -- Set_Etype (Full, Full_Base);
9444 -- then we get inconsistencies in the front-end (confusion between
9445 -- views). Several outstanding bugs are related to this ???
9447 Set_Is_First_Subtype (Full, False);
9448 Set_Scope (Full, Scope (Priv));
9449 Set_Size_Info (Full, Full_Base);
9450 Set_RM_Size (Full, RM_Size (Full_Base));
9451 Set_Is_Itype (Full);
9453 -- A subtype of a private-type-without-discriminants, whose full-view
9454 -- has discriminants with default expressions, is not constrained!
9456 if not Has_Discriminants (Priv) then
9457 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
9459 if Has_Discriminants (Full_Base) then
9460 Set_Discriminant_Constraint
9461 (Full, Discriminant_Constraint (Full_Base));
9463 -- The partial view may have been indefinite, the full view
9466 Set_Has_Unknown_Discriminants
9467 (Full, Has_Unknown_Discriminants (Full_Base));
9471 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
9472 Set_Depends_On_Private (Full, Has_Private_Component (Full));
9474 -- Freeze the private subtype entity if its parent is delayed, and not
9475 -- already frozen. We skip this processing if the type is an anonymous
9476 -- subtype of a record component, or is the corresponding record of a
9477 -- protected type, since ???
9479 if not Is_Type (Scope (Full)) then
9480 Set_Has_Delayed_Freeze (Full,
9481 Has_Delayed_Freeze (Full_Base)
9482 and then (not Is_Frozen (Full_Base)));
9485 Set_Freeze_Node (Full, Empty);
9486 Set_Is_Frozen (Full, False);
9487 Set_Full_View (Priv, Full);
9489 if Has_Discriminants (Full) then
9490 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
9491 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
9493 if Has_Unknown_Discriminants (Full) then
9494 Set_Discriminant_Constraint (Full, No_Elist);
9498 if Ekind (Full_Base) = E_Record_Type
9499 and then Has_Discriminants (Full_Base)
9500 and then Has_Discriminants (Priv) -- might not, if errors
9501 and then not Has_Unknown_Discriminants (Priv)
9502 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
9504 Create_Constrained_Components
9505 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
9507 -- If the full base is itself derived from private, build a congruent
9508 -- subtype of its underlying type, for use by the back end. For a
9509 -- constrained record component, the declaration cannot be placed on
9510 -- the component list, but it must nevertheless be built an analyzed, to
9511 -- supply enough information for Gigi to compute the size of component.
9513 elsif Ekind (Full_Base) in Private_Kind
9514 and then Is_Derived_Type (Full_Base)
9515 and then Has_Discriminants (Full_Base)
9516 and then (Ekind (Current_Scope) /= E_Record_Subtype)
9518 if not Is_Itype (Priv)
9520 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
9522 Build_Underlying_Full_View
9523 (Parent (Priv), Full, Etype (Full_Base));
9525 elsif Nkind (Related_Nod) = N_Component_Declaration then
9526 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
9529 elsif Is_Record_Type (Full_Base) then
9531 -- Show Full is simply a renaming of Full_Base
9533 Set_Cloned_Subtype (Full, Full_Base);
9536 -- It is unsafe to share to bounds of a scalar type, because the Itype
9537 -- is elaborated on demand, and if a bound is non-static then different
9538 -- orders of elaboration in different units will lead to different
9539 -- external symbols.
9541 if Is_Scalar_Type (Full_Base) then
9542 Set_Scalar_Range (Full,
9543 Make_Range (Sloc (Related_Nod),
9545 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
9547 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
9549 -- This completion inherits the bounds of the full parent, but if
9550 -- the parent is an unconstrained floating point type, so is the
9553 if Is_Floating_Point_Type (Full_Base) then
9554 Set_Includes_Infinities
9555 (Scalar_Range (Full), Has_Infinities (Full_Base));
9559 -- ??? It seems that a lot of fields are missing that should be copied
9560 -- from Full_Base to Full. Here are some that are introduced in a
9561 -- non-disruptive way but a cleanup is necessary.
9563 if Is_Tagged_Type (Full_Base) then
9564 Set_Is_Tagged_Type (Full);
9565 Set_Primitive_Operations (Full, Primitive_Operations (Full_Base));
9566 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
9568 -- If this is a subtype of a protected or task type, constrain its
9569 -- corresponding record, unless this is a subtype without constraints,
9570 -- i.e. a simple renaming as with an actual subtype in an instance.
9572 elsif Is_Concurrent_Type (Full_Base) then
9573 if Has_Discriminants (Full)
9574 and then Present (Corresponding_Record_Type (Full_Base))
9576 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
9578 Set_Corresponding_Record_Type (Full,
9579 Constrain_Corresponding_Record
9580 (Full, Corresponding_Record_Type (Full_Base),
9581 Related_Nod, Full_Base));
9584 Set_Corresponding_Record_Type (Full,
9585 Corresponding_Record_Type (Full_Base));
9588 end Complete_Private_Subtype;
9590 ----------------------------
9591 -- Constant_Redeclaration --
9592 ----------------------------
9594 procedure Constant_Redeclaration
9599 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
9600 Obj_Def : constant Node_Id := Object_Definition (N);
9603 procedure Check_Possible_Deferred_Completion
9604 (Prev_Id : Entity_Id;
9605 Prev_Obj_Def : Node_Id;
9606 Curr_Obj_Def : Node_Id);
9607 -- Determine whether the two object definitions describe the partial
9608 -- and the full view of a constrained deferred constant. Generate
9609 -- a subtype for the full view and verify that it statically matches
9610 -- the subtype of the partial view.
9612 procedure Check_Recursive_Declaration (Typ : Entity_Id);
9613 -- If deferred constant is an access type initialized with an allocator,
9614 -- check whether there is an illegal recursion in the definition,
9615 -- through a default value of some record subcomponent. This is normally
9616 -- detected when generating init procs, but requires this additional
9617 -- mechanism when expansion is disabled.
9619 ----------------------------------------
9620 -- Check_Possible_Deferred_Completion --
9621 ----------------------------------------
9623 procedure Check_Possible_Deferred_Completion
9624 (Prev_Id : Entity_Id;
9625 Prev_Obj_Def : Node_Id;
9626 Curr_Obj_Def : Node_Id)
9629 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
9630 and then Present (Constraint (Prev_Obj_Def))
9631 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
9632 and then Present (Constraint (Curr_Obj_Def))
9635 Loc : constant Source_Ptr := Sloc (N);
9636 Def_Id : constant Entity_Id :=
9637 Make_Defining_Identifier (Loc,
9638 New_Internal_Name ('S'));
9639 Decl : constant Node_Id :=
9640 Make_Subtype_Declaration (Loc,
9641 Defining_Identifier =>
9643 Subtype_Indication =>
9644 Relocate_Node (Curr_Obj_Def));
9647 Insert_Before_And_Analyze (N, Decl);
9648 Set_Etype (Id, Def_Id);
9650 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
9651 Error_Msg_Sloc := Sloc (Prev_Id);
9652 Error_Msg_N ("subtype does not statically match deferred " &
9657 end Check_Possible_Deferred_Completion;
9659 ---------------------------------
9660 -- Check_Recursive_Declaration --
9661 ---------------------------------
9663 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
9667 if Is_Record_Type (Typ) then
9668 Comp := First_Component (Typ);
9669 while Present (Comp) loop
9670 if Comes_From_Source (Comp) then
9671 if Present (Expression (Parent (Comp)))
9672 and then Is_Entity_Name (Expression (Parent (Comp)))
9673 and then Entity (Expression (Parent (Comp))) = Prev
9675 Error_Msg_Sloc := Sloc (Parent (Comp));
9677 ("illegal circularity with declaration for&#",
9681 elsif Is_Record_Type (Etype (Comp)) then
9682 Check_Recursive_Declaration (Etype (Comp));
9686 Next_Component (Comp);
9689 end Check_Recursive_Declaration;
9691 -- Start of processing for Constant_Redeclaration
9694 if Nkind (Parent (Prev)) = N_Object_Declaration then
9695 if Nkind (Object_Definition
9696 (Parent (Prev))) = N_Subtype_Indication
9698 -- Find type of new declaration. The constraints of the two
9699 -- views must match statically, but there is no point in
9700 -- creating an itype for the full view.
9702 if Nkind (Obj_Def) = N_Subtype_Indication then
9703 Find_Type (Subtype_Mark (Obj_Def));
9704 New_T := Entity (Subtype_Mark (Obj_Def));
9707 Find_Type (Obj_Def);
9708 New_T := Entity (Obj_Def);
9714 -- The full view may impose a constraint, even if the partial
9715 -- view does not, so construct the subtype.
9717 New_T := Find_Type_Of_Object (Obj_Def, N);
9722 -- Current declaration is illegal, diagnosed below in Enter_Name
9728 -- If previous full declaration exists, or if a homograph is present,
9729 -- let Enter_Name handle it, either with an error, or with the removal
9730 -- of an overridden implicit subprogram.
9732 if Ekind (Prev) /= E_Constant
9733 or else Present (Expression (Parent (Prev)))
9734 or else Present (Full_View (Prev))
9738 -- Verify that types of both declarations match, or else that both types
9739 -- are anonymous access types whose designated subtypes statically match
9740 -- (as allowed in Ada 2005 by AI-385).
9742 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
9744 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
9745 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
9746 or else Is_Access_Constant (Etype (New_T)) /=
9747 Is_Access_Constant (Etype (Prev))
9748 or else Can_Never_Be_Null (Etype (New_T)) /=
9749 Can_Never_Be_Null (Etype (Prev))
9750 or else Null_Exclusion_Present (Parent (Prev)) /=
9751 Null_Exclusion_Present (Parent (Id))
9752 or else not Subtypes_Statically_Match
9753 (Designated_Type (Etype (Prev)),
9754 Designated_Type (Etype (New_T))))
9756 Error_Msg_Sloc := Sloc (Prev);
9757 Error_Msg_N ("type does not match declaration#", N);
9758 Set_Full_View (Prev, Id);
9759 Set_Etype (Id, Any_Type);
9762 Null_Exclusion_Present (Parent (Prev))
9763 and then not Null_Exclusion_Present (N)
9765 Error_Msg_Sloc := Sloc (Prev);
9766 Error_Msg_N ("null-exclusion does not match declaration#", N);
9767 Set_Full_View (Prev, Id);
9768 Set_Etype (Id, Any_Type);
9770 -- If so, process the full constant declaration
9773 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
9774 -- the deferred declaration is constrained, then the subtype defined
9775 -- by the subtype_indication in the full declaration shall match it
9778 Check_Possible_Deferred_Completion
9780 Prev_Obj_Def => Object_Definition (Parent (Prev)),
9781 Curr_Obj_Def => Obj_Def);
9783 Set_Full_View (Prev, Id);
9784 Set_Is_Public (Id, Is_Public (Prev));
9785 Set_Is_Internal (Id);
9786 Append_Entity (Id, Current_Scope);
9788 -- Check ALIASED present if present before (RM 7.4(7))
9790 if Is_Aliased (Prev)
9791 and then not Aliased_Present (N)
9793 Error_Msg_Sloc := Sloc (Prev);
9794 Error_Msg_N ("ALIASED required (see declaration#)", N);
9797 -- Check that placement is in private part and that the incomplete
9798 -- declaration appeared in the visible part.
9800 if Ekind (Current_Scope) = E_Package
9801 and then not In_Private_Part (Current_Scope)
9803 Error_Msg_Sloc := Sloc (Prev);
9804 Error_Msg_N ("full constant for declaration#"
9805 & " must be in private part", N);
9807 elsif Ekind (Current_Scope) = E_Package
9808 and then List_Containing (Parent (Prev))
9809 /= Visible_Declarations
9810 (Specification (Unit_Declaration_Node (Current_Scope)))
9813 ("deferred constant must be declared in visible part",
9817 if Is_Access_Type (T)
9818 and then Nkind (Expression (N)) = N_Allocator
9820 Check_Recursive_Declaration (Designated_Type (T));
9823 end Constant_Redeclaration;
9825 ----------------------
9826 -- Constrain_Access --
9827 ----------------------
9829 procedure Constrain_Access
9830 (Def_Id : in out Entity_Id;
9832 Related_Nod : Node_Id)
9834 T : constant Entity_Id := Entity (Subtype_Mark (S));
9835 Desig_Type : constant Entity_Id := Designated_Type (T);
9836 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
9837 Constraint_OK : Boolean := True;
9839 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean;
9840 -- Simple predicate to test for defaulted discriminants
9841 -- Shouldn't this be in sem_util???
9843 ---------------------------------
9844 -- Has_Defaulted_Discriminants --
9845 ---------------------------------
9847 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean is
9849 return Has_Discriminants (Typ)
9850 and then Present (First_Discriminant (Typ))
9852 (Discriminant_Default_Value (First_Discriminant (Typ)));
9853 end Has_Defaulted_Discriminants;
9855 -- Start of processing for Constrain_Access
9858 if Is_Array_Type (Desig_Type) then
9859 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
9861 elsif (Is_Record_Type (Desig_Type)
9862 or else Is_Incomplete_Or_Private_Type (Desig_Type))
9863 and then not Is_Constrained (Desig_Type)
9865 -- ??? The following code is a temporary kludge to ignore a
9866 -- discriminant constraint on access type if it is constraining
9867 -- the current record. Avoid creating the implicit subtype of the
9868 -- record we are currently compiling since right now, we cannot
9869 -- handle these. For now, just return the access type itself.
9871 if Desig_Type = Current_Scope
9872 and then No (Def_Id)
9874 Set_Ekind (Desig_Subtype, E_Record_Subtype);
9875 Def_Id := Entity (Subtype_Mark (S));
9877 -- This call added to ensure that the constraint is analyzed
9878 -- (needed for a B test). Note that we still return early from
9879 -- this procedure to avoid recursive processing. ???
9881 Constrain_Discriminated_Type
9882 (Desig_Subtype, S, Related_Nod, For_Access => True);
9886 if (Ekind (T) = E_General_Access_Type
9887 or else Ada_Version >= Ada_05)
9888 and then Has_Private_Declaration (Desig_Type)
9889 and then In_Open_Scopes (Scope (Desig_Type))
9890 and then Has_Discriminants (Desig_Type)
9892 -- Enforce rule that the constraint is illegal if there is
9893 -- an unconstrained view of the designated type. This means
9894 -- that the partial view (either a private type declaration or
9895 -- a derivation from a private type) has no discriminants.
9896 -- (Defect Report 8652/0008, Technical Corrigendum 1, checked
9897 -- by ACATS B371001).
9899 -- Rule updated for Ada 2005: the private type is said to have
9900 -- a constrained partial view, given that objects of the type
9901 -- can be declared. Furthermore, the rule applies to all access
9902 -- types, unlike the rule concerning default discriminants.
9905 Pack : constant Node_Id :=
9906 Unit_Declaration_Node (Scope (Desig_Type));
9911 if Nkind (Pack) = N_Package_Declaration then
9912 Decls := Visible_Declarations (Specification (Pack));
9913 Decl := First (Decls);
9914 while Present (Decl) loop
9915 if (Nkind (Decl) = N_Private_Type_Declaration
9917 Chars (Defining_Identifier (Decl)) =
9921 (Nkind (Decl) = N_Full_Type_Declaration
9923 Chars (Defining_Identifier (Decl)) =
9925 and then Is_Derived_Type (Desig_Type)
9927 Has_Private_Declaration (Etype (Desig_Type)))
9929 if No (Discriminant_Specifications (Decl)) then
9931 ("cannot constrain general access type if " &
9932 "designated type has constrained partial view",
9945 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
9946 For_Access => True);
9948 elsif (Is_Task_Type (Desig_Type)
9949 or else Is_Protected_Type (Desig_Type))
9950 and then not Is_Constrained (Desig_Type)
9952 Constrain_Concurrent
9953 (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
9956 Error_Msg_N ("invalid constraint on access type", S);
9957 Desig_Subtype := Desig_Type; -- Ignore invalid constraint.
9958 Constraint_OK := False;
9962 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
9964 Set_Ekind (Def_Id, E_Access_Subtype);
9967 if Constraint_OK then
9968 Set_Etype (Def_Id, Base_Type (T));
9970 if Is_Private_Type (Desig_Type) then
9971 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
9974 Set_Etype (Def_Id, Any_Type);
9977 Set_Size_Info (Def_Id, T);
9978 Set_Is_Constrained (Def_Id, Constraint_OK);
9979 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
9980 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
9981 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
9983 Conditional_Delay (Def_Id, T);
9985 -- AI-363 : Subtypes of general access types whose designated types have
9986 -- default discriminants are disallowed. In instances, the rule has to
9987 -- be checked against the actual, of which T is the subtype. In a
9988 -- generic body, the rule is checked assuming that the actual type has
9989 -- defaulted discriminants.
9991 if Ada_Version >= Ada_05 or else Warn_On_Ada_2005_Compatibility then
9992 if Ekind (Base_Type (T)) = E_General_Access_Type
9993 and then Has_Defaulted_Discriminants (Desig_Type)
9995 if Ada_Version < Ada_05 then
9997 ("access subtype of general access type would not " &
9998 "be allowed in Ada 2005?", S);
10001 ("access subype of general access type not allowed", S);
10004 Error_Msg_N ("\discriminants have defaults", S);
10006 elsif Is_Access_Type (T)
10007 and then Is_Generic_Type (Desig_Type)
10008 and then Has_Discriminants (Desig_Type)
10009 and then In_Package_Body (Current_Scope)
10011 if Ada_Version < Ada_05 then
10013 ("access subtype would not be allowed in generic body " &
10014 "in Ada 2005?", S);
10017 ("access subtype not allowed in generic body", S);
10021 ("\designated type is a discriminated formal", S);
10024 end Constrain_Access;
10026 ---------------------
10027 -- Constrain_Array --
10028 ---------------------
10030 procedure Constrain_Array
10031 (Def_Id : in out Entity_Id;
10033 Related_Nod : Node_Id;
10034 Related_Id : Entity_Id;
10035 Suffix : Character)
10037 C : constant Node_Id := Constraint (SI);
10038 Number_Of_Constraints : Nat := 0;
10041 Constraint_OK : Boolean := True;
10044 T := Entity (Subtype_Mark (SI));
10046 if Ekind (T) in Access_Kind then
10047 T := Designated_Type (T);
10050 -- If an index constraint follows a subtype mark in a subtype indication
10051 -- then the type or subtype denoted by the subtype mark must not already
10052 -- impose an index constraint. The subtype mark must denote either an
10053 -- unconstrained array type or an access type whose designated type
10054 -- is such an array type... (RM 3.6.1)
10056 if Is_Constrained (T) then
10058 ("array type is already constrained", Subtype_Mark (SI));
10059 Constraint_OK := False;
10062 S := First (Constraints (C));
10063 while Present (S) loop
10064 Number_Of_Constraints := Number_Of_Constraints + 1;
10068 -- In either case, the index constraint must provide a discrete
10069 -- range for each index of the array type and the type of each
10070 -- discrete range must be the same as that of the corresponding
10071 -- index. (RM 3.6.1)
10073 if Number_Of_Constraints /= Number_Dimensions (T) then
10074 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
10075 Constraint_OK := False;
10078 S := First (Constraints (C));
10079 Index := First_Index (T);
10082 -- Apply constraints to each index type
10084 for J in 1 .. Number_Of_Constraints loop
10085 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
10093 if No (Def_Id) then
10095 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
10096 Set_Parent (Def_Id, Related_Nod);
10099 Set_Ekind (Def_Id, E_Array_Subtype);
10102 Set_Size_Info (Def_Id, (T));
10103 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10104 Set_Etype (Def_Id, Base_Type (T));
10106 if Constraint_OK then
10107 Set_First_Index (Def_Id, First (Constraints (C)));
10109 Set_First_Index (Def_Id, First_Index (T));
10112 Set_Is_Constrained (Def_Id, True);
10113 Set_Is_Aliased (Def_Id, Is_Aliased (T));
10114 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10116 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
10117 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
10119 -- A subtype does not inherit the packed_array_type of is parent. We
10120 -- need to initialize the attribute because if Def_Id is previously
10121 -- analyzed through a limited_with clause, it will have the attributes
10122 -- of an incomplete type, one of which is an Elist that overlaps the
10123 -- Packed_Array_Type field.
10125 Set_Packed_Array_Type (Def_Id, Empty);
10127 -- Build a freeze node if parent still needs one. Also make sure that
10128 -- the Depends_On_Private status is set because the subtype will need
10129 -- reprocessing at the time the base type does, and also we must set a
10130 -- conditional delay.
10132 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
10133 Conditional_Delay (Def_Id, T);
10134 end Constrain_Array;
10136 ------------------------------
10137 -- Constrain_Component_Type --
10138 ------------------------------
10140 function Constrain_Component_Type
10142 Constrained_Typ : Entity_Id;
10143 Related_Node : Node_Id;
10145 Constraints : Elist_Id) return Entity_Id
10147 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
10148 Compon_Type : constant Entity_Id := Etype (Comp);
10150 function Build_Constrained_Array_Type
10151 (Old_Type : Entity_Id) return Entity_Id;
10152 -- If Old_Type is an array type, one of whose indices is constrained
10153 -- by a discriminant, build an Itype whose constraint replaces the
10154 -- discriminant with its value in the constraint.
10156 function Build_Constrained_Discriminated_Type
10157 (Old_Type : Entity_Id) return Entity_Id;
10158 -- Ditto for record components
10160 function Build_Constrained_Access_Type
10161 (Old_Type : Entity_Id) return Entity_Id;
10162 -- Ditto for access types. Makes use of previous two functions, to
10163 -- constrain designated type.
10165 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
10166 -- T is an array or discriminated type, C is a list of constraints
10167 -- that apply to T. This routine builds the constrained subtype.
10169 function Is_Discriminant (Expr : Node_Id) return Boolean;
10170 -- Returns True if Expr is a discriminant
10172 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
10173 -- Find the value of discriminant Discrim in Constraint
10175 -----------------------------------
10176 -- Build_Constrained_Access_Type --
10177 -----------------------------------
10179 function Build_Constrained_Access_Type
10180 (Old_Type : Entity_Id) return Entity_Id
10182 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
10184 Desig_Subtype : Entity_Id;
10188 -- if the original access type was not embedded in the enclosing
10189 -- type definition, there is no need to produce a new access
10190 -- subtype. In fact every access type with an explicit constraint
10191 -- generates an itype whose scope is the enclosing record.
10193 if not Is_Type (Scope (Old_Type)) then
10196 elsif Is_Array_Type (Desig_Type) then
10197 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
10199 elsif Has_Discriminants (Desig_Type) then
10201 -- This may be an access type to an enclosing record type for
10202 -- which we are constructing the constrained components. Return
10203 -- the enclosing record subtype. This is not always correct,
10204 -- but avoids infinite recursion. ???
10206 Desig_Subtype := Any_Type;
10208 for J in reverse 0 .. Scope_Stack.Last loop
10209 Scop := Scope_Stack.Table (J).Entity;
10212 and then Base_Type (Scop) = Base_Type (Desig_Type)
10214 Desig_Subtype := Scop;
10217 exit when not Is_Type (Scop);
10220 if Desig_Subtype = Any_Type then
10222 Build_Constrained_Discriminated_Type (Desig_Type);
10229 if Desig_Subtype /= Desig_Type then
10231 -- The Related_Node better be here or else we won't be able
10232 -- to attach new itypes to a node in the tree.
10234 pragma Assert (Present (Related_Node));
10236 Itype := Create_Itype (E_Access_Subtype, Related_Node);
10238 Set_Etype (Itype, Base_Type (Old_Type));
10239 Set_Size_Info (Itype, (Old_Type));
10240 Set_Directly_Designated_Type (Itype, Desig_Subtype);
10241 Set_Depends_On_Private (Itype, Has_Private_Component
10243 Set_Is_Access_Constant (Itype, Is_Access_Constant
10246 -- The new itype needs freezing when it depends on a not frozen
10247 -- type and the enclosing subtype needs freezing.
10249 if Has_Delayed_Freeze (Constrained_Typ)
10250 and then not Is_Frozen (Constrained_Typ)
10252 Conditional_Delay (Itype, Base_Type (Old_Type));
10260 end Build_Constrained_Access_Type;
10262 ----------------------------------
10263 -- Build_Constrained_Array_Type --
10264 ----------------------------------
10266 function Build_Constrained_Array_Type
10267 (Old_Type : Entity_Id) return Entity_Id
10271 Old_Index : Node_Id;
10272 Range_Node : Node_Id;
10273 Constr_List : List_Id;
10275 Need_To_Create_Itype : Boolean := False;
10278 Old_Index := First_Index (Old_Type);
10279 while Present (Old_Index) loop
10280 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
10282 if Is_Discriminant (Lo_Expr)
10283 or else Is_Discriminant (Hi_Expr)
10285 Need_To_Create_Itype := True;
10288 Next_Index (Old_Index);
10291 if Need_To_Create_Itype then
10292 Constr_List := New_List;
10294 Old_Index := First_Index (Old_Type);
10295 while Present (Old_Index) loop
10296 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
10298 if Is_Discriminant (Lo_Expr) then
10299 Lo_Expr := Get_Discr_Value (Lo_Expr);
10302 if Is_Discriminant (Hi_Expr) then
10303 Hi_Expr := Get_Discr_Value (Hi_Expr);
10308 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
10310 Append (Range_Node, To => Constr_List);
10312 Next_Index (Old_Index);
10315 return Build_Subtype (Old_Type, Constr_List);
10320 end Build_Constrained_Array_Type;
10322 ------------------------------------------
10323 -- Build_Constrained_Discriminated_Type --
10324 ------------------------------------------
10326 function Build_Constrained_Discriminated_Type
10327 (Old_Type : Entity_Id) return Entity_Id
10330 Constr_List : List_Id;
10331 Old_Constraint : Elmt_Id;
10333 Need_To_Create_Itype : Boolean := False;
10336 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
10337 while Present (Old_Constraint) loop
10338 Expr := Node (Old_Constraint);
10340 if Is_Discriminant (Expr) then
10341 Need_To_Create_Itype := True;
10344 Next_Elmt (Old_Constraint);
10347 if Need_To_Create_Itype then
10348 Constr_List := New_List;
10350 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
10351 while Present (Old_Constraint) loop
10352 Expr := Node (Old_Constraint);
10354 if Is_Discriminant (Expr) then
10355 Expr := Get_Discr_Value (Expr);
10358 Append (New_Copy_Tree (Expr), To => Constr_List);
10360 Next_Elmt (Old_Constraint);
10363 return Build_Subtype (Old_Type, Constr_List);
10368 end Build_Constrained_Discriminated_Type;
10370 -------------------
10371 -- Build_Subtype --
10372 -------------------
10374 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
10376 Subtyp_Decl : Node_Id;
10377 Def_Id : Entity_Id;
10378 Btyp : Entity_Id := Base_Type (T);
10381 -- The Related_Node better be here or else we won't be able to
10382 -- attach new itypes to a node in the tree.
10384 pragma Assert (Present (Related_Node));
10386 -- If the view of the component's type is incomplete or private
10387 -- with unknown discriminants, then the constraint must be applied
10388 -- to the full type.
10390 if Has_Unknown_Discriminants (Btyp)
10391 and then Present (Underlying_Type (Btyp))
10393 Btyp := Underlying_Type (Btyp);
10397 Make_Subtype_Indication (Loc,
10398 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
10399 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
10401 Def_Id := Create_Itype (Ekind (T), Related_Node);
10404 Make_Subtype_Declaration (Loc,
10405 Defining_Identifier => Def_Id,
10406 Subtype_Indication => Indic);
10408 Set_Parent (Subtyp_Decl, Parent (Related_Node));
10410 -- Itypes must be analyzed with checks off (see package Itypes)
10412 Analyze (Subtyp_Decl, Suppress => All_Checks);
10417 ---------------------
10418 -- Get_Discr_Value --
10419 ---------------------
10421 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
10426 -- The discriminant may be declared for the type, in which case we
10427 -- find it by iterating over the list of discriminants. If the
10428 -- discriminant is inherited from a parent type, it appears as the
10429 -- corresponding discriminant of the current type. This will be the
10430 -- case when constraining an inherited component whose constraint is
10431 -- given by a discriminant of the parent.
10433 D := First_Discriminant (Typ);
10434 E := First_Elmt (Constraints);
10436 while Present (D) loop
10437 if D = Entity (Discrim)
10438 or else D = CR_Discriminant (Entity (Discrim))
10439 or else Corresponding_Discriminant (D) = Entity (Discrim)
10444 Next_Discriminant (D);
10448 -- The corresponding_Discriminant mechanism is incomplete, because
10449 -- the correspondence between new and old discriminants is not one
10450 -- to one: one new discriminant can constrain several old ones. In
10451 -- that case, scan sequentially the stored_constraint, the list of
10452 -- discriminants of the parents, and the constraints.
10453 -- Previous code checked for the present of the Stored_Constraint
10454 -- list for the derived type, but did not use it at all. Should it
10455 -- be present when the component is a discriminated task type?
10457 if Is_Derived_Type (Typ)
10458 and then Scope (Entity (Discrim)) = Etype (Typ)
10460 D := First_Discriminant (Etype (Typ));
10461 E := First_Elmt (Constraints);
10462 while Present (D) loop
10463 if D = Entity (Discrim) then
10467 Next_Discriminant (D);
10472 -- Something is wrong if we did not find the value
10474 raise Program_Error;
10475 end Get_Discr_Value;
10477 ---------------------
10478 -- Is_Discriminant --
10479 ---------------------
10481 function Is_Discriminant (Expr : Node_Id) return Boolean is
10482 Discrim_Scope : Entity_Id;
10485 if Denotes_Discriminant (Expr) then
10486 Discrim_Scope := Scope (Entity (Expr));
10488 -- Either we have a reference to one of Typ's discriminants,
10490 pragma Assert (Discrim_Scope = Typ
10492 -- or to the discriminants of the parent type, in the case
10493 -- of a derivation of a tagged type with variants.
10495 or else Discrim_Scope = Etype (Typ)
10496 or else Full_View (Discrim_Scope) = Etype (Typ)
10498 -- or same as above for the case where the discriminants
10499 -- were declared in Typ's private view.
10501 or else (Is_Private_Type (Discrim_Scope)
10502 and then Chars (Discrim_Scope) = Chars (Typ))
10504 -- or else we are deriving from the full view and the
10505 -- discriminant is declared in the private entity.
10507 or else (Is_Private_Type (Typ)
10508 and then Chars (Discrim_Scope) = Chars (Typ))
10510 -- Or we are constrained the corresponding record of a
10511 -- synchronized type that completes a private declaration.
10513 or else (Is_Concurrent_Record_Type (Typ)
10515 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
10517 -- or we have a class-wide type, in which case make sure the
10518 -- discriminant found belongs to the root type.
10520 or else (Is_Class_Wide_Type (Typ)
10521 and then Etype (Typ) = Discrim_Scope));
10526 -- In all other cases we have something wrong
10529 end Is_Discriminant;
10531 -- Start of processing for Constrain_Component_Type
10534 if Nkind (Parent (Comp)) = N_Component_Declaration
10535 and then Comes_From_Source (Parent (Comp))
10536 and then Comes_From_Source
10537 (Subtype_Indication (Component_Definition (Parent (Comp))))
10540 (Subtype_Indication (Component_Definition (Parent (Comp))))
10542 return Compon_Type;
10544 elsif Is_Array_Type (Compon_Type) then
10545 return Build_Constrained_Array_Type (Compon_Type);
10547 elsif Has_Discriminants (Compon_Type) then
10548 return Build_Constrained_Discriminated_Type (Compon_Type);
10550 elsif Is_Access_Type (Compon_Type) then
10551 return Build_Constrained_Access_Type (Compon_Type);
10554 return Compon_Type;
10556 end Constrain_Component_Type;
10558 --------------------------
10559 -- Constrain_Concurrent --
10560 --------------------------
10562 -- For concurrent types, the associated record value type carries the same
10563 -- discriminants, so when we constrain a concurrent type, we must constrain
10564 -- the corresponding record type as well.
10566 procedure Constrain_Concurrent
10567 (Def_Id : in out Entity_Id;
10569 Related_Nod : Node_Id;
10570 Related_Id : Entity_Id;
10571 Suffix : Character)
10573 T_Ent : Entity_Id := Entity (Subtype_Mark (SI));
10577 if Ekind (T_Ent) in Access_Kind then
10578 T_Ent := Designated_Type (T_Ent);
10581 T_Val := Corresponding_Record_Type (T_Ent);
10583 if Present (T_Val) then
10585 if No (Def_Id) then
10586 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
10589 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
10591 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10592 Set_Corresponding_Record_Type (Def_Id,
10593 Constrain_Corresponding_Record
10594 (Def_Id, T_Val, Related_Nod, Related_Id));
10597 -- If there is no associated record, expansion is disabled and this
10598 -- is a generic context. Create a subtype in any case, so that
10599 -- semantic analysis can proceed.
10601 if No (Def_Id) then
10602 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
10605 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
10607 end Constrain_Concurrent;
10609 ------------------------------------
10610 -- Constrain_Corresponding_Record --
10611 ------------------------------------
10613 function Constrain_Corresponding_Record
10614 (Prot_Subt : Entity_Id;
10615 Corr_Rec : Entity_Id;
10616 Related_Nod : Node_Id;
10617 Related_Id : Entity_Id) return Entity_Id
10619 T_Sub : constant Entity_Id :=
10620 Create_Itype (E_Record_Subtype, Related_Nod, Related_Id, 'V');
10623 Set_Etype (T_Sub, Corr_Rec);
10624 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
10625 Set_Is_Constrained (T_Sub, True);
10626 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
10627 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
10629 -- As elsewhere, we do not want to create a freeze node for this itype
10630 -- if it is created for a constrained component of an enclosing record
10631 -- because references to outer discriminants will appear out of scope.
10633 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
10634 Conditional_Delay (T_Sub, Corr_Rec);
10636 Set_Is_Frozen (T_Sub);
10639 if Has_Discriminants (Prot_Subt) then -- False only if errors.
10640 Set_Discriminant_Constraint
10641 (T_Sub, Discriminant_Constraint (Prot_Subt));
10642 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
10643 Create_Constrained_Components
10644 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
10647 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
10650 end Constrain_Corresponding_Record;
10652 -----------------------
10653 -- Constrain_Decimal --
10654 -----------------------
10656 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
10657 T : constant Entity_Id := Entity (Subtype_Mark (S));
10658 C : constant Node_Id := Constraint (S);
10659 Loc : constant Source_Ptr := Sloc (C);
10660 Range_Expr : Node_Id;
10661 Digits_Expr : Node_Id;
10666 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
10668 if Nkind (C) = N_Range_Constraint then
10669 Range_Expr := Range_Expression (C);
10670 Digits_Val := Digits_Value (T);
10673 pragma Assert (Nkind (C) = N_Digits_Constraint);
10674 Digits_Expr := Digits_Expression (C);
10675 Analyze_And_Resolve (Digits_Expr, Any_Integer);
10677 Check_Digits_Expression (Digits_Expr);
10678 Digits_Val := Expr_Value (Digits_Expr);
10680 if Digits_Val > Digits_Value (T) then
10682 ("digits expression is incompatible with subtype", C);
10683 Digits_Val := Digits_Value (T);
10686 if Present (Range_Constraint (C)) then
10687 Range_Expr := Range_Expression (Range_Constraint (C));
10689 Range_Expr := Empty;
10693 Set_Etype (Def_Id, Base_Type (T));
10694 Set_Size_Info (Def_Id, (T));
10695 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10696 Set_Delta_Value (Def_Id, Delta_Value (T));
10697 Set_Scale_Value (Def_Id, Scale_Value (T));
10698 Set_Small_Value (Def_Id, Small_Value (T));
10699 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
10700 Set_Digits_Value (Def_Id, Digits_Val);
10702 -- Manufacture range from given digits value if no range present
10704 if No (Range_Expr) then
10705 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
10709 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
10711 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
10714 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
10715 Set_Discrete_RM_Size (Def_Id);
10717 -- Unconditionally delay the freeze, since we cannot set size
10718 -- information in all cases correctly until the freeze point.
10720 Set_Has_Delayed_Freeze (Def_Id);
10721 end Constrain_Decimal;
10723 ----------------------------------
10724 -- Constrain_Discriminated_Type --
10725 ----------------------------------
10727 procedure Constrain_Discriminated_Type
10728 (Def_Id : Entity_Id;
10730 Related_Nod : Node_Id;
10731 For_Access : Boolean := False)
10733 E : constant Entity_Id := Entity (Subtype_Mark (S));
10736 Elist : Elist_Id := New_Elmt_List;
10738 procedure Fixup_Bad_Constraint;
10739 -- This is called after finding a bad constraint, and after having
10740 -- posted an appropriate error message. The mission is to leave the
10741 -- entity T in as reasonable state as possible!
10743 --------------------------
10744 -- Fixup_Bad_Constraint --
10745 --------------------------
10747 procedure Fixup_Bad_Constraint is
10749 -- Set a reasonable Ekind for the entity. For an incomplete type,
10750 -- we can't do much, but for other types, we can set the proper
10751 -- corresponding subtype kind.
10753 if Ekind (T) = E_Incomplete_Type then
10754 Set_Ekind (Def_Id, Ekind (T));
10756 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
10759 -- Set Etype to the known type, to reduce chances of cascaded errors
10761 Set_Etype (Def_Id, E);
10762 Set_Error_Posted (Def_Id);
10763 end Fixup_Bad_Constraint;
10765 -- Start of processing for Constrain_Discriminated_Type
10768 C := Constraint (S);
10770 -- A discriminant constraint is only allowed in a subtype indication,
10771 -- after a subtype mark. This subtype mark must denote either a type
10772 -- with discriminants, or an access type whose designated type is a
10773 -- type with discriminants. A discriminant constraint specifies the
10774 -- values of these discriminants (RM 3.7.2(5)).
10776 T := Base_Type (Entity (Subtype_Mark (S)));
10778 if Ekind (T) in Access_Kind then
10779 T := Designated_Type (T);
10782 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
10783 -- Avoid generating an error for access-to-incomplete subtypes.
10785 if Ada_Version >= Ada_05
10786 and then Ekind (T) = E_Incomplete_Type
10787 and then Nkind (Parent (S)) = N_Subtype_Declaration
10788 and then not Is_Itype (Def_Id)
10790 -- A little sanity check, emit an error message if the type
10791 -- has discriminants to begin with. Type T may be a regular
10792 -- incomplete type or imported via a limited with clause.
10794 if Has_Discriminants (T)
10796 (From_With_Type (T)
10797 and then Present (Non_Limited_View (T))
10798 and then Nkind (Parent (Non_Limited_View (T))) =
10799 N_Full_Type_Declaration
10800 and then Present (Discriminant_Specifications
10801 (Parent (Non_Limited_View (T)))))
10804 ("(Ada 2005) incomplete subtype may not be constrained", C);
10807 ("invalid constraint: type has no discriminant", C);
10810 Fixup_Bad_Constraint;
10813 -- Check that the type has visible discriminants. The type may be
10814 -- a private type with unknown discriminants whose full view has
10815 -- discriminants which are invisible.
10817 elsif not Has_Discriminants (T)
10819 (Has_Unknown_Discriminants (T)
10820 and then Is_Private_Type (T))
10822 Error_Msg_N ("invalid constraint: type has no discriminant", C);
10823 Fixup_Bad_Constraint;
10826 elsif Is_Constrained (E)
10827 or else (Ekind (E) = E_Class_Wide_Subtype
10828 and then Present (Discriminant_Constraint (E)))
10830 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
10831 Fixup_Bad_Constraint;
10835 -- T may be an unconstrained subtype (e.g. a generic actual).
10836 -- Constraint applies to the base type.
10838 T := Base_Type (T);
10840 Elist := Build_Discriminant_Constraints (T, S);
10842 -- If the list returned was empty we had an error in building the
10843 -- discriminant constraint. We have also already signalled an error
10844 -- in the incomplete type case
10846 if Is_Empty_Elmt_List (Elist) then
10847 Fixup_Bad_Constraint;
10851 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
10852 end Constrain_Discriminated_Type;
10854 ---------------------------
10855 -- Constrain_Enumeration --
10856 ---------------------------
10858 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
10859 T : constant Entity_Id := Entity (Subtype_Mark (S));
10860 C : constant Node_Id := Constraint (S);
10863 Set_Ekind (Def_Id, E_Enumeration_Subtype);
10865 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
10867 Set_Etype (Def_Id, Base_Type (T));
10868 Set_Size_Info (Def_Id, (T));
10869 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10870 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
10872 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
10874 Set_Discrete_RM_Size (Def_Id);
10875 end Constrain_Enumeration;
10877 ----------------------
10878 -- Constrain_Float --
10879 ----------------------
10881 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
10882 T : constant Entity_Id := Entity (Subtype_Mark (S));
10888 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
10890 Set_Etype (Def_Id, Base_Type (T));
10891 Set_Size_Info (Def_Id, (T));
10892 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10894 -- Process the constraint
10896 C := Constraint (S);
10898 -- Digits constraint present
10900 if Nkind (C) = N_Digits_Constraint then
10901 Check_Restriction (No_Obsolescent_Features, C);
10903 if Warn_On_Obsolescent_Feature then
10905 ("subtype digits constraint is an " &
10906 "obsolescent feature (RM J.3(8))?", C);
10909 D := Digits_Expression (C);
10910 Analyze_And_Resolve (D, Any_Integer);
10911 Check_Digits_Expression (D);
10912 Set_Digits_Value (Def_Id, Expr_Value (D));
10914 -- Check that digits value is in range. Obviously we can do this
10915 -- at compile time, but it is strictly a runtime check, and of
10916 -- course there is an ACVC test that checks this!
10918 if Digits_Value (Def_Id) > Digits_Value (T) then
10919 Error_Msg_Uint_1 := Digits_Value (T);
10920 Error_Msg_N ("?digits value is too large, maximum is ^", D);
10922 Make_Raise_Constraint_Error (Sloc (D),
10923 Reason => CE_Range_Check_Failed);
10924 Insert_Action (Declaration_Node (Def_Id), Rais);
10927 C := Range_Constraint (C);
10929 -- No digits constraint present
10932 Set_Digits_Value (Def_Id, Digits_Value (T));
10935 -- Range constraint present
10937 if Nkind (C) = N_Range_Constraint then
10938 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
10940 -- No range constraint present
10943 pragma Assert (No (C));
10944 Set_Scalar_Range (Def_Id, Scalar_Range (T));
10947 Set_Is_Constrained (Def_Id);
10948 end Constrain_Float;
10950 ---------------------
10951 -- Constrain_Index --
10952 ---------------------
10954 procedure Constrain_Index
10957 Related_Nod : Node_Id;
10958 Related_Id : Entity_Id;
10959 Suffix : Character;
10960 Suffix_Index : Nat)
10962 Def_Id : Entity_Id;
10963 R : Node_Id := Empty;
10964 T : constant Entity_Id := Etype (Index);
10967 if Nkind (S) = N_Range
10969 (Nkind (S) = N_Attribute_Reference
10970 and then Attribute_Name (S) = Name_Range)
10972 -- A Range attribute will transformed into N_Range by Resolve
10978 Process_Range_Expr_In_Decl (R, T, Empty_List);
10980 if not Error_Posted (S)
10982 (Nkind (S) /= N_Range
10983 or else not Covers (T, (Etype (Low_Bound (S))))
10984 or else not Covers (T, (Etype (High_Bound (S)))))
10986 if Base_Type (T) /= Any_Type
10987 and then Etype (Low_Bound (S)) /= Any_Type
10988 and then Etype (High_Bound (S)) /= Any_Type
10990 Error_Msg_N ("range expected", S);
10994 elsif Nkind (S) = N_Subtype_Indication then
10996 -- The parser has verified that this is a discrete indication
10998 Resolve_Discrete_Subtype_Indication (S, T);
10999 R := Range_Expression (Constraint (S));
11001 elsif Nkind (S) = N_Discriminant_Association then
11003 -- Syntactically valid in subtype indication
11005 Error_Msg_N ("invalid index constraint", S);
11006 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11009 -- Subtype_Mark case, no anonymous subtypes to construct
11014 if Is_Entity_Name (S) then
11015 if not Is_Type (Entity (S)) then
11016 Error_Msg_N ("expect subtype mark for index constraint", S);
11018 elsif Base_Type (Entity (S)) /= Base_Type (T) then
11019 Wrong_Type (S, Base_Type (T));
11025 Error_Msg_N ("invalid index constraint", S);
11026 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11032 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
11034 Set_Etype (Def_Id, Base_Type (T));
11036 if Is_Modular_Integer_Type (T) then
11037 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11039 elsif Is_Integer_Type (T) then
11040 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11043 Set_Ekind (Def_Id, E_Enumeration_Subtype);
11044 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
11047 Set_Size_Info (Def_Id, (T));
11048 Set_RM_Size (Def_Id, RM_Size (T));
11049 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11051 Set_Scalar_Range (Def_Id, R);
11053 Set_Etype (S, Def_Id);
11054 Set_Discrete_RM_Size (Def_Id);
11055 end Constrain_Index;
11057 -----------------------
11058 -- Constrain_Integer --
11059 -----------------------
11061 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
11062 T : constant Entity_Id := Entity (Subtype_Mark (S));
11063 C : constant Node_Id := Constraint (S);
11066 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11068 if Is_Modular_Integer_Type (T) then
11069 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11071 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11074 Set_Etype (Def_Id, Base_Type (T));
11075 Set_Size_Info (Def_Id, (T));
11076 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11077 Set_Discrete_RM_Size (Def_Id);
11078 end Constrain_Integer;
11080 ------------------------------
11081 -- Constrain_Ordinary_Fixed --
11082 ------------------------------
11084 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
11085 T : constant Entity_Id := Entity (Subtype_Mark (S));
11091 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
11092 Set_Etype (Def_Id, Base_Type (T));
11093 Set_Size_Info (Def_Id, (T));
11094 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11095 Set_Small_Value (Def_Id, Small_Value (T));
11097 -- Process the constraint
11099 C := Constraint (S);
11101 -- Delta constraint present
11103 if Nkind (C) = N_Delta_Constraint then
11104 Check_Restriction (No_Obsolescent_Features, C);
11106 if Warn_On_Obsolescent_Feature then
11108 ("subtype delta constraint is an " &
11109 "obsolescent feature (RM J.3(7))?");
11112 D := Delta_Expression (C);
11113 Analyze_And_Resolve (D, Any_Real);
11114 Check_Delta_Expression (D);
11115 Set_Delta_Value (Def_Id, Expr_Value_R (D));
11117 -- Check that delta value is in range. Obviously we can do this
11118 -- at compile time, but it is strictly a runtime check, and of
11119 -- course there is an ACVC test that checks this!
11121 if Delta_Value (Def_Id) < Delta_Value (T) then
11122 Error_Msg_N ("?delta value is too small", D);
11124 Make_Raise_Constraint_Error (Sloc (D),
11125 Reason => CE_Range_Check_Failed);
11126 Insert_Action (Declaration_Node (Def_Id), Rais);
11129 C := Range_Constraint (C);
11131 -- No delta constraint present
11134 Set_Delta_Value (Def_Id, Delta_Value (T));
11137 -- Range constraint present
11139 if Nkind (C) = N_Range_Constraint then
11140 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11142 -- No range constraint present
11145 pragma Assert (No (C));
11146 Set_Scalar_Range (Def_Id, Scalar_Range (T));
11150 Set_Discrete_RM_Size (Def_Id);
11152 -- Unconditionally delay the freeze, since we cannot set size
11153 -- information in all cases correctly until the freeze point.
11155 Set_Has_Delayed_Freeze (Def_Id);
11156 end Constrain_Ordinary_Fixed;
11158 -----------------------
11159 -- Contain_Interface --
11160 -----------------------
11162 function Contain_Interface
11163 (Iface : Entity_Id;
11164 Ifaces : Elist_Id) return Boolean
11166 Iface_Elmt : Elmt_Id;
11169 if Present (Ifaces) then
11170 Iface_Elmt := First_Elmt (Ifaces);
11171 while Present (Iface_Elmt) loop
11172 if Node (Iface_Elmt) = Iface then
11176 Next_Elmt (Iface_Elmt);
11181 end Contain_Interface;
11183 ---------------------------
11184 -- Convert_Scalar_Bounds --
11185 ---------------------------
11187 procedure Convert_Scalar_Bounds
11189 Parent_Type : Entity_Id;
11190 Derived_Type : Entity_Id;
11193 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
11200 Lo := Build_Scalar_Bound
11201 (Type_Low_Bound (Derived_Type),
11202 Parent_Type, Implicit_Base);
11204 Hi := Build_Scalar_Bound
11205 (Type_High_Bound (Derived_Type),
11206 Parent_Type, Implicit_Base);
11213 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
11215 Set_Parent (Rng, N);
11216 Set_Scalar_Range (Derived_Type, Rng);
11218 -- Analyze the bounds
11220 Analyze_And_Resolve (Lo, Implicit_Base);
11221 Analyze_And_Resolve (Hi, Implicit_Base);
11223 -- Analyze the range itself, except that we do not analyze it if
11224 -- the bounds are real literals, and we have a fixed-point type.
11225 -- The reason for this is that we delay setting the bounds in this
11226 -- case till we know the final Small and Size values (see circuit
11227 -- in Freeze.Freeze_Fixed_Point_Type for further details).
11229 if Is_Fixed_Point_Type (Parent_Type)
11230 and then Nkind (Lo) = N_Real_Literal
11231 and then Nkind (Hi) = N_Real_Literal
11235 -- Here we do the analysis of the range
11237 -- Note: we do this manually, since if we do a normal Analyze and
11238 -- Resolve call, there are problems with the conversions used for
11239 -- the derived type range.
11242 Set_Etype (Rng, Implicit_Base);
11243 Set_Analyzed (Rng, True);
11245 end Convert_Scalar_Bounds;
11247 -------------------
11248 -- Copy_And_Swap --
11249 -------------------
11251 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
11253 -- Initialize new full declaration entity by copying the pertinent
11254 -- fields of the corresponding private declaration entity.
11256 -- We temporarily set Ekind to a value appropriate for a type to
11257 -- avoid assert failures in Einfo from checking for setting type
11258 -- attributes on something that is not a type. Ekind (Priv) is an
11259 -- appropriate choice, since it allowed the attributes to be set
11260 -- in the first place. This Ekind value will be modified later.
11262 Set_Ekind (Full, Ekind (Priv));
11264 -- Also set Etype temporarily to Any_Type, again, in the absence
11265 -- of errors, it will be properly reset, and if there are errors,
11266 -- then we want a value of Any_Type to remain.
11268 Set_Etype (Full, Any_Type);
11270 -- Now start copying attributes
11272 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
11274 if Has_Discriminants (Full) then
11275 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
11276 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
11279 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
11280 Set_Homonym (Full, Homonym (Priv));
11281 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
11282 Set_Is_Public (Full, Is_Public (Priv));
11283 Set_Is_Pure (Full, Is_Pure (Priv));
11284 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
11285 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
11286 Set_Has_Pragma_Unreferenced_Objects
11287 (Full, Has_Pragma_Unreferenced_Objects
11290 Conditional_Delay (Full, Priv);
11292 if Is_Tagged_Type (Full) then
11293 Set_Primitive_Operations (Full, Primitive_Operations (Priv));
11295 if Priv = Base_Type (Priv) then
11296 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
11300 Set_Is_Volatile (Full, Is_Volatile (Priv));
11301 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
11302 Set_Scope (Full, Scope (Priv));
11303 Set_Next_Entity (Full, Next_Entity (Priv));
11304 Set_First_Entity (Full, First_Entity (Priv));
11305 Set_Last_Entity (Full, Last_Entity (Priv));
11307 -- If access types have been recorded for later handling, keep them in
11308 -- the full view so that they get handled when the full view freeze
11309 -- node is expanded.
11311 if Present (Freeze_Node (Priv))
11312 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
11314 Ensure_Freeze_Node (Full);
11315 Set_Access_Types_To_Process
11316 (Freeze_Node (Full),
11317 Access_Types_To_Process (Freeze_Node (Priv)));
11320 -- Swap the two entities. Now Privat is the full type entity and
11321 -- Full is the private one. They will be swapped back at the end
11322 -- of the private part. This swapping ensures that the entity that
11323 -- is visible in the private part is the full declaration.
11325 Exchange_Entities (Priv, Full);
11326 Append_Entity (Full, Scope (Full));
11329 -------------------------------------
11330 -- Copy_Array_Base_Type_Attributes --
11331 -------------------------------------
11333 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
11335 Set_Component_Alignment (T1, Component_Alignment (T2));
11336 Set_Component_Type (T1, Component_Type (T2));
11337 Set_Component_Size (T1, Component_Size (T2));
11338 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
11339 Set_Finalize_Storage_Only (T1, Finalize_Storage_Only (T2));
11340 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
11341 Set_Has_Task (T1, Has_Task (T2));
11342 Set_Is_Packed (T1, Is_Packed (T2));
11343 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
11344 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
11345 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
11346 end Copy_Array_Base_Type_Attributes;
11348 -----------------------------------
11349 -- Copy_Array_Subtype_Attributes --
11350 -----------------------------------
11352 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
11354 Set_Size_Info (T1, T2);
11356 Set_First_Index (T1, First_Index (T2));
11357 Set_Is_Aliased (T1, Is_Aliased (T2));
11358 Set_Is_Atomic (T1, Is_Atomic (T2));
11359 Set_Is_Volatile (T1, Is_Volatile (T2));
11360 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
11361 Set_Is_Constrained (T1, Is_Constrained (T2));
11362 Set_Depends_On_Private (T1, Has_Private_Component (T2));
11363 Set_First_Rep_Item (T1, First_Rep_Item (T2));
11364 Set_Convention (T1, Convention (T2));
11365 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
11366 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
11367 Set_Packed_Array_Type (T1, Packed_Array_Type (T2));
11368 end Copy_Array_Subtype_Attributes;
11370 -----------------------------------
11371 -- Create_Constrained_Components --
11372 -----------------------------------
11374 procedure Create_Constrained_Components
11376 Decl_Node : Node_Id;
11378 Constraints : Elist_Id)
11380 Loc : constant Source_Ptr := Sloc (Subt);
11381 Comp_List : constant Elist_Id := New_Elmt_List;
11382 Parent_Type : constant Entity_Id := Etype (Typ);
11383 Assoc_List : constant List_Id := New_List;
11384 Discr_Val : Elmt_Id;
11388 Is_Static : Boolean := True;
11390 procedure Collect_Fixed_Components (Typ : Entity_Id);
11391 -- Collect parent type components that do not appear in a variant part
11393 procedure Create_All_Components;
11394 -- Iterate over Comp_List to create the components of the subtype
11396 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
11397 -- Creates a new component from Old_Compon, copying all the fields from
11398 -- it, including its Etype, inserts the new component in the Subt entity
11399 -- chain and returns the new component.
11401 function Is_Variant_Record (T : Entity_Id) return Boolean;
11402 -- If true, and discriminants are static, collect only components from
11403 -- variants selected by discriminant values.
11405 ------------------------------
11406 -- Collect_Fixed_Components --
11407 ------------------------------
11409 procedure Collect_Fixed_Components (Typ : Entity_Id) is
11411 -- Build association list for discriminants, and find components of the
11412 -- variant part selected by the values of the discriminants.
11414 Old_C := First_Discriminant (Typ);
11415 Discr_Val := First_Elmt (Constraints);
11416 while Present (Old_C) loop
11417 Append_To (Assoc_List,
11418 Make_Component_Association (Loc,
11419 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
11420 Expression => New_Copy (Node (Discr_Val))));
11422 Next_Elmt (Discr_Val);
11423 Next_Discriminant (Old_C);
11426 -- The tag, and the possible parent and controller components
11427 -- are unconditionally in the subtype.
11429 if Is_Tagged_Type (Typ)
11430 or else Has_Controlled_Component (Typ)
11432 Old_C := First_Component (Typ);
11433 while Present (Old_C) loop
11434 if Chars ((Old_C)) = Name_uTag
11435 or else Chars ((Old_C)) = Name_uParent
11436 or else Chars ((Old_C)) = Name_uController
11438 Append_Elmt (Old_C, Comp_List);
11441 Next_Component (Old_C);
11444 end Collect_Fixed_Components;
11446 ---------------------------
11447 -- Create_All_Components --
11448 ---------------------------
11450 procedure Create_All_Components is
11454 Comp := First_Elmt (Comp_List);
11455 while Present (Comp) loop
11456 Old_C := Node (Comp);
11457 New_C := Create_Component (Old_C);
11461 Constrain_Component_Type
11462 (Old_C, Subt, Decl_Node, Typ, Constraints));
11463 Set_Is_Public (New_C, Is_Public (Subt));
11467 end Create_All_Components;
11469 ----------------------
11470 -- Create_Component --
11471 ----------------------
11473 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
11474 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
11477 if Ekind (Old_Compon) = E_Discriminant
11478 and then Is_Completely_Hidden (Old_Compon)
11480 -- This is a shadow discriminant created for a discriminant of
11481 -- the parent type, which needs to be present in the subtype.
11482 -- Give the shadow discriminant an internal name that cannot
11483 -- conflict with that of visible components.
11485 Set_Chars (New_Compon, New_Internal_Name ('C'));
11488 -- Set the parent so we have a proper link for freezing etc. This is
11489 -- not a real parent pointer, since of course our parent does not own
11490 -- up to us and reference us, we are an illegitimate child of the
11491 -- original parent!
11493 Set_Parent (New_Compon, Parent (Old_Compon));
11495 -- If the old component's Esize was already determined and is a
11496 -- static value, then the new component simply inherits it. Otherwise
11497 -- the old component's size may require run-time determination, but
11498 -- the new component's size still might be statically determinable
11499 -- (if, for example it has a static constraint). In that case we want
11500 -- Layout_Type to recompute the component's size, so we reset its
11501 -- size and positional fields.
11503 if Frontend_Layout_On_Target
11504 and then not Known_Static_Esize (Old_Compon)
11506 Set_Esize (New_Compon, Uint_0);
11507 Init_Normalized_First_Bit (New_Compon);
11508 Init_Normalized_Position (New_Compon);
11509 Init_Normalized_Position_Max (New_Compon);
11512 -- We do not want this node marked as Comes_From_Source, since
11513 -- otherwise it would get first class status and a separate cross-
11514 -- reference line would be generated. Illegitimate children do not
11515 -- rate such recognition.
11517 Set_Comes_From_Source (New_Compon, False);
11519 -- But it is a real entity, and a birth certificate must be properly
11520 -- registered by entering it into the entity list.
11522 Enter_Name (New_Compon);
11525 end Create_Component;
11527 -----------------------
11528 -- Is_Variant_Record --
11529 -----------------------
11531 function Is_Variant_Record (T : Entity_Id) return Boolean is
11533 return Nkind (Parent (T)) = N_Full_Type_Declaration
11534 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
11535 and then Present (Component_List (Type_Definition (Parent (T))))
11538 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
11539 end Is_Variant_Record;
11541 -- Start of processing for Create_Constrained_Components
11544 pragma Assert (Subt /= Base_Type (Subt));
11545 pragma Assert (Typ = Base_Type (Typ));
11547 Set_First_Entity (Subt, Empty);
11548 Set_Last_Entity (Subt, Empty);
11550 -- Check whether constraint is fully static, in which case we can
11551 -- optimize the list of components.
11553 Discr_Val := First_Elmt (Constraints);
11554 while Present (Discr_Val) loop
11555 if not Is_OK_Static_Expression (Node (Discr_Val)) then
11556 Is_Static := False;
11560 Next_Elmt (Discr_Val);
11563 Set_Has_Static_Discriminants (Subt, Is_Static);
11567 -- Inherit the discriminants of the parent type
11569 Add_Discriminants : declare
11575 Old_C := First_Discriminant (Typ);
11577 while Present (Old_C) loop
11578 Num_Disc := Num_Disc + 1;
11579 New_C := Create_Component (Old_C);
11580 Set_Is_Public (New_C, Is_Public (Subt));
11581 Next_Discriminant (Old_C);
11584 -- For an untagged derived subtype, the number of discriminants may
11585 -- be smaller than the number of inherited discriminants, because
11586 -- several of them may be renamed by a single new discriminant or
11587 -- constrained. In this case, add the hidden discriminants back into
11588 -- the subtype, because they need to be present if the optimizer of
11589 -- the GCC 4.x back-end decides to break apart assignments between
11590 -- objects using the parent view into member-wise assignments.
11594 if Is_Derived_Type (Typ)
11595 and then not Is_Tagged_Type (Typ)
11597 Old_C := First_Stored_Discriminant (Typ);
11599 while Present (Old_C) loop
11600 Num_Gird := Num_Gird + 1;
11601 Next_Stored_Discriminant (Old_C);
11605 if Num_Gird > Num_Disc then
11607 -- Find out multiple uses of new discriminants, and add hidden
11608 -- components for the extra renamed discriminants. We recognize
11609 -- multiple uses through the Corresponding_Discriminant of a
11610 -- new discriminant: if it constrains several old discriminants,
11611 -- this field points to the last one in the parent type. The
11612 -- stored discriminants of the derived type have the same name
11613 -- as those of the parent.
11617 New_Discr : Entity_Id;
11618 Old_Discr : Entity_Id;
11621 Constr := First_Elmt (Stored_Constraint (Typ));
11622 Old_Discr := First_Stored_Discriminant (Typ);
11623 while Present (Constr) loop
11624 if Is_Entity_Name (Node (Constr))
11625 and then Ekind (Entity (Node (Constr))) = E_Discriminant
11627 New_Discr := Entity (Node (Constr));
11629 if Chars (Corresponding_Discriminant (New_Discr)) /=
11632 -- The new discriminant has been used to rename a
11633 -- subsequent old discriminant. Introduce a shadow
11634 -- component for the current old discriminant.
11636 New_C := Create_Component (Old_Discr);
11637 Set_Original_Record_Component (New_C, Old_Discr);
11641 -- The constraint has eliminated the old discriminant.
11642 -- Introduce a shadow component.
11644 New_C := Create_Component (Old_Discr);
11645 Set_Original_Record_Component (New_C, Old_Discr);
11648 Next_Elmt (Constr);
11649 Next_Stored_Discriminant (Old_Discr);
11653 end Add_Discriminants;
11656 and then Is_Variant_Record (Typ)
11658 Collect_Fixed_Components (Typ);
11660 Gather_Components (
11662 Component_List (Type_Definition (Parent (Typ))),
11663 Governed_By => Assoc_List,
11665 Report_Errors => Errors);
11666 pragma Assert (not Errors);
11668 Create_All_Components;
11670 -- If the subtype declaration is created for a tagged type derivation
11671 -- with constraints, we retrieve the record definition of the parent
11672 -- type to select the components of the proper variant.
11675 and then Is_Tagged_Type (Typ)
11676 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
11678 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
11679 and then Is_Variant_Record (Parent_Type)
11681 Collect_Fixed_Components (Typ);
11683 Gather_Components (
11685 Component_List (Type_Definition (Parent (Parent_Type))),
11686 Governed_By => Assoc_List,
11688 Report_Errors => Errors);
11689 pragma Assert (not Errors);
11691 -- If the tagged derivation has a type extension, collect all the
11692 -- new components therein.
11695 (Record_Extension_Part (Type_Definition (Parent (Typ))))
11697 Old_C := First_Component (Typ);
11698 while Present (Old_C) loop
11699 if Original_Record_Component (Old_C) = Old_C
11700 and then Chars (Old_C) /= Name_uTag
11701 and then Chars (Old_C) /= Name_uParent
11702 and then Chars (Old_C) /= Name_uController
11704 Append_Elmt (Old_C, Comp_List);
11707 Next_Component (Old_C);
11711 Create_All_Components;
11714 -- If discriminants are not static, or if this is a multi-level type
11715 -- extension, we have to include all components of the parent type.
11717 Old_C := First_Component (Typ);
11718 while Present (Old_C) loop
11719 New_C := Create_Component (Old_C);
11723 Constrain_Component_Type
11724 (Old_C, Subt, Decl_Node, Typ, Constraints));
11725 Set_Is_Public (New_C, Is_Public (Subt));
11727 Next_Component (Old_C);
11732 end Create_Constrained_Components;
11734 ------------------------------------------
11735 -- Decimal_Fixed_Point_Type_Declaration --
11736 ------------------------------------------
11738 procedure Decimal_Fixed_Point_Type_Declaration
11742 Loc : constant Source_Ptr := Sloc (Def);
11743 Digs_Expr : constant Node_Id := Digits_Expression (Def);
11744 Delta_Expr : constant Node_Id := Delta_Expression (Def);
11745 Implicit_Base : Entity_Id;
11752 Check_Restriction (No_Fixed_Point, Def);
11754 -- Create implicit base type
11757 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
11758 Set_Etype (Implicit_Base, Implicit_Base);
11760 -- Analyze and process delta expression
11762 Analyze_And_Resolve (Delta_Expr, Universal_Real);
11764 Check_Delta_Expression (Delta_Expr);
11765 Delta_Val := Expr_Value_R (Delta_Expr);
11767 -- Check delta is power of 10, and determine scale value from it
11773 Scale_Val := Uint_0;
11776 if Val < Ureal_1 then
11777 while Val < Ureal_1 loop
11778 Val := Val * Ureal_10;
11779 Scale_Val := Scale_Val + 1;
11782 if Scale_Val > 18 then
11783 Error_Msg_N ("scale exceeds maximum value of 18", Def);
11784 Scale_Val := UI_From_Int (+18);
11788 while Val > Ureal_1 loop
11789 Val := Val / Ureal_10;
11790 Scale_Val := Scale_Val - 1;
11793 if Scale_Val < -18 then
11794 Error_Msg_N ("scale is less than minimum value of -18", Def);
11795 Scale_Val := UI_From_Int (-18);
11799 if Val /= Ureal_1 then
11800 Error_Msg_N ("delta expression must be a power of 10", Def);
11801 Delta_Val := Ureal_10 ** (-Scale_Val);
11805 -- Set delta, scale and small (small = delta for decimal type)
11807 Set_Delta_Value (Implicit_Base, Delta_Val);
11808 Set_Scale_Value (Implicit_Base, Scale_Val);
11809 Set_Small_Value (Implicit_Base, Delta_Val);
11811 -- Analyze and process digits expression
11813 Analyze_And_Resolve (Digs_Expr, Any_Integer);
11814 Check_Digits_Expression (Digs_Expr);
11815 Digs_Val := Expr_Value (Digs_Expr);
11817 if Digs_Val > 18 then
11818 Digs_Val := UI_From_Int (+18);
11819 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
11822 Set_Digits_Value (Implicit_Base, Digs_Val);
11823 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
11825 -- Set range of base type from digits value for now. This will be
11826 -- expanded to represent the true underlying base range by Freeze.
11828 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
11830 -- Note: We leave size as zero for now, size will be set at freeze
11831 -- time. We have to do this for ordinary fixed-point, because the size
11832 -- depends on the specified small, and we might as well do the same for
11833 -- decimal fixed-point.
11835 pragma Assert (Esize (Implicit_Base) = Uint_0);
11837 -- If there are bounds given in the declaration use them as the
11838 -- bounds of the first named subtype.
11840 if Present (Real_Range_Specification (Def)) then
11842 RRS : constant Node_Id := Real_Range_Specification (Def);
11843 Low : constant Node_Id := Low_Bound (RRS);
11844 High : constant Node_Id := High_Bound (RRS);
11849 Analyze_And_Resolve (Low, Any_Real);
11850 Analyze_And_Resolve (High, Any_Real);
11851 Check_Real_Bound (Low);
11852 Check_Real_Bound (High);
11853 Low_Val := Expr_Value_R (Low);
11854 High_Val := Expr_Value_R (High);
11856 if Low_Val < (-Bound_Val) then
11858 ("range low bound too small for digits value", Low);
11859 Low_Val := -Bound_Val;
11862 if High_Val > Bound_Val then
11864 ("range high bound too large for digits value", High);
11865 High_Val := Bound_Val;
11868 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
11871 -- If no explicit range, use range that corresponds to given
11872 -- digits value. This will end up as the final range for the
11876 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
11879 -- Complete entity for first subtype
11881 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
11882 Set_Etype (T, Implicit_Base);
11883 Set_Size_Info (T, Implicit_Base);
11884 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
11885 Set_Digits_Value (T, Digs_Val);
11886 Set_Delta_Value (T, Delta_Val);
11887 Set_Small_Value (T, Delta_Val);
11888 Set_Scale_Value (T, Scale_Val);
11889 Set_Is_Constrained (T);
11890 end Decimal_Fixed_Point_Type_Declaration;
11892 -----------------------------------
11893 -- Derive_Progenitor_Subprograms --
11894 -----------------------------------
11896 procedure Derive_Progenitor_Subprograms
11897 (Parent_Type : Entity_Id;
11898 Tagged_Type : Entity_Id)
11903 Iface_Elmt : Elmt_Id;
11904 Iface_Subp : Entity_Id;
11905 New_Subp : Entity_Id := Empty;
11906 Prim_Elmt : Elmt_Id;
11911 pragma Assert (Ada_Version >= Ada_05
11912 and then Is_Record_Type (Tagged_Type)
11913 and then Is_Tagged_Type (Tagged_Type)
11914 and then Has_Interfaces (Tagged_Type));
11916 -- Step 1: Transfer to the full-view primitives associated with the
11917 -- partial-view that cover interface primitives. Conceptually this
11918 -- work should be done later by Process_Full_View; done here to
11919 -- simplify its implementation at later stages. It can be safely
11920 -- done here because interfaces must be visible in the partial and
11921 -- private view (RM 7.3(7.3/2)).
11923 -- Small optimization: This work is only required if the parent is
11924 -- abstract. If the tagged type is not abstract, it cannot have
11925 -- abstract primitives (the only entities in the list of primitives of
11926 -- non-abstract tagged types that can reference abstract primitives
11927 -- through its Alias attribute are the internal entities that have
11928 -- attribute Interface_Alias, and these entities are generated later
11929 -- by Freeze_Record_Type).
11931 if In_Private_Part (Current_Scope)
11932 and then Is_Abstract_Type (Parent_Type)
11934 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
11935 while Present (Elmt) loop
11936 Subp := Node (Elmt);
11938 -- At this stage it is not possible to have entities in the list
11939 -- of primitives that have attribute Interface_Alias
11941 pragma Assert (No (Interface_Alias (Subp)));
11943 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
11945 if Is_Interface (Typ) then
11946 E := Find_Primitive_Covering_Interface
11947 (Tagged_Type => Tagged_Type,
11948 Iface_Prim => Subp);
11951 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
11953 Replace_Elmt (Elmt, E);
11954 Remove_Homonym (Subp);
11962 -- Step 2: Add primitives of progenitors that are not implemented by
11963 -- parents of Tagged_Type
11965 if Present (Interfaces (Base_Type (Tagged_Type))) then
11966 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
11967 while Present (Iface_Elmt) loop
11968 Iface := Node (Iface_Elmt);
11970 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
11971 while Present (Prim_Elmt) loop
11972 Iface_Subp := Node (Prim_Elmt);
11974 -- Exclude derivation of predefined primitives except those
11975 -- that come from source. Required to catch declarations of
11976 -- equality operators of interfaces. For example:
11978 -- type Iface is interface;
11979 -- function "=" (Left, Right : Iface) return Boolean;
11981 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
11982 or else Comes_From_Source (Iface_Subp)
11984 E := Find_Primitive_Covering_Interface
11985 (Tagged_Type => Tagged_Type,
11986 Iface_Prim => Iface_Subp);
11988 -- If not found we derive a new primitive leaving its alias
11989 -- attribute referencing the interface primitive
11993 (New_Subp, Iface_Subp, Tagged_Type, Iface);
11995 -- Propagate to the full view interface entities associated
11996 -- with the partial view
11998 elsif In_Private_Part (Current_Scope)
11999 and then Present (Alias (E))
12000 and then Alias (E) = Iface_Subp
12002 List_Containing (Parent (E)) /=
12003 Private_Declarations
12005 (Unit_Declaration_Node (Current_Scope)))
12007 Append_Elmt (E, Primitive_Operations (Tagged_Type));
12011 Next_Elmt (Prim_Elmt);
12014 Next_Elmt (Iface_Elmt);
12017 end Derive_Progenitor_Subprograms;
12019 -----------------------
12020 -- Derive_Subprogram --
12021 -----------------------
12023 procedure Derive_Subprogram
12024 (New_Subp : in out Entity_Id;
12025 Parent_Subp : Entity_Id;
12026 Derived_Type : Entity_Id;
12027 Parent_Type : Entity_Id;
12028 Actual_Subp : Entity_Id := Empty)
12030 Formal : Entity_Id;
12031 -- Formal parameter of parent primitive operation
12033 Formal_Of_Actual : Entity_Id;
12034 -- Formal parameter of actual operation, when the derivation is to
12035 -- create a renaming for a primitive operation of an actual in an
12038 New_Formal : Entity_Id;
12039 -- Formal of inherited operation
12041 Visible_Subp : Entity_Id := Parent_Subp;
12043 function Is_Private_Overriding return Boolean;
12044 -- If Subp is a private overriding of a visible operation, the inherited
12045 -- operation derives from the overridden op (even though its body is the
12046 -- overriding one) and the inherited operation is visible now. See
12047 -- sem_disp to see the full details of the handling of the overridden
12048 -- subprogram, which is removed from the list of primitive operations of
12049 -- the type. The overridden subprogram is saved locally in Visible_Subp,
12050 -- and used to diagnose abstract operations that need overriding in the
12053 procedure Replace_Type (Id, New_Id : Entity_Id);
12054 -- When the type is an anonymous access type, create a new access type
12055 -- designating the derived type.
12057 procedure Set_Derived_Name;
12058 -- This procedure sets the appropriate Chars name for New_Subp. This
12059 -- is normally just a copy of the parent name. An exception arises for
12060 -- type support subprograms, where the name is changed to reflect the
12061 -- name of the derived type, e.g. if type foo is derived from type bar,
12062 -- then a procedure barDA is derived with a name fooDA.
12064 ---------------------------
12065 -- Is_Private_Overriding --
12066 ---------------------------
12068 function Is_Private_Overriding return Boolean is
12072 -- If the parent is not a dispatching operation there is no
12073 -- need to investigate overridings
12075 if not Is_Dispatching_Operation (Parent_Subp) then
12079 -- The visible operation that is overridden is a homonym of the
12080 -- parent subprogram. We scan the homonym chain to find the one
12081 -- whose alias is the subprogram we are deriving.
12083 Prev := Current_Entity (Parent_Subp);
12084 while Present (Prev) loop
12085 if Ekind (Prev) = Ekind (Parent_Subp)
12086 and then Alias (Prev) = Parent_Subp
12087 and then Scope (Parent_Subp) = Scope (Prev)
12088 and then not Is_Hidden (Prev)
12090 Visible_Subp := Prev;
12094 Prev := Homonym (Prev);
12098 end Is_Private_Overriding;
12104 procedure Replace_Type (Id, New_Id : Entity_Id) is
12105 Acc_Type : Entity_Id;
12106 Par : constant Node_Id := Parent (Derived_Type);
12109 -- When the type is an anonymous access type, create a new access
12110 -- type designating the derived type. This itype must be elaborated
12111 -- at the point of the derivation, not on subsequent calls that may
12112 -- be out of the proper scope for Gigi, so we insert a reference to
12113 -- it after the derivation.
12115 if Ekind (Etype (Id)) = E_Anonymous_Access_Type then
12117 Desig_Typ : Entity_Id := Designated_Type (Etype (Id));
12120 if Ekind (Desig_Typ) = E_Record_Type_With_Private
12121 and then Present (Full_View (Desig_Typ))
12122 and then not Is_Private_Type (Parent_Type)
12124 Desig_Typ := Full_View (Desig_Typ);
12127 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
12129 -- Ada 2005 (AI-251): Handle also derivations of abstract
12130 -- interface primitives.
12132 or else (Is_Interface (Desig_Typ)
12133 and then not Is_Class_Wide_Type (Desig_Typ))
12135 Acc_Type := New_Copy (Etype (Id));
12136 Set_Etype (Acc_Type, Acc_Type);
12137 Set_Scope (Acc_Type, New_Subp);
12139 -- Compute size of anonymous access type
12141 if Is_Array_Type (Desig_Typ)
12142 and then not Is_Constrained (Desig_Typ)
12144 Init_Size (Acc_Type, 2 * System_Address_Size);
12146 Init_Size (Acc_Type, System_Address_Size);
12149 Init_Alignment (Acc_Type);
12150 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
12152 Set_Etype (New_Id, Acc_Type);
12153 Set_Scope (New_Id, New_Subp);
12155 -- Create a reference to it
12156 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
12159 Set_Etype (New_Id, Etype (Id));
12163 elsif Base_Type (Etype (Id)) = Base_Type (Parent_Type)
12165 (Ekind (Etype (Id)) = E_Record_Type_With_Private
12166 and then Present (Full_View (Etype (Id)))
12168 Base_Type (Full_View (Etype (Id))) = Base_Type (Parent_Type))
12170 -- Constraint checks on formals are generated during expansion,
12171 -- based on the signature of the original subprogram. The bounds
12172 -- of the derived type are not relevant, and thus we can use
12173 -- the base type for the formals. However, the return type may be
12174 -- used in a context that requires that the proper static bounds
12175 -- be used (a case statement, for example) and for those cases
12176 -- we must use the derived type (first subtype), not its base.
12178 -- If the derived_type_definition has no constraints, we know that
12179 -- the derived type has the same constraints as the first subtype
12180 -- of the parent, and we can also use it rather than its base,
12181 -- which can lead to more efficient code.
12183 if Etype (Id) = Parent_Type then
12184 if Is_Scalar_Type (Parent_Type)
12186 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
12188 Set_Etype (New_Id, Derived_Type);
12190 elsif Nkind (Par) = N_Full_Type_Declaration
12192 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
12195 (Subtype_Indication (Type_Definition (Par)))
12197 Set_Etype (New_Id, Derived_Type);
12200 Set_Etype (New_Id, Base_Type (Derived_Type));
12204 Set_Etype (New_Id, Base_Type (Derived_Type));
12207 -- Ada 2005 (AI-251): Handle derivations of abstract interface
12210 elsif Is_Interface (Etype (Id))
12211 and then not Is_Class_Wide_Type (Etype (Id))
12212 and then Is_Progenitor (Etype (Id), Derived_Type)
12214 Set_Etype (New_Id, Derived_Type);
12217 Set_Etype (New_Id, Etype (Id));
12221 ----------------------
12222 -- Set_Derived_Name --
12223 ----------------------
12225 procedure Set_Derived_Name is
12226 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
12228 if Nm = TSS_Null then
12229 Set_Chars (New_Subp, Chars (Parent_Subp));
12231 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
12233 end Set_Derived_Name;
12237 Parent_Overrides_Interface_Primitive : Boolean := False;
12239 -- Start of processing for Derive_Subprogram
12243 New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
12244 Set_Ekind (New_Subp, Ekind (Parent_Subp));
12246 -- Check whether the parent overrides an interface primitive
12248 if Is_Overriding_Operation (Parent_Subp) then
12250 E : Entity_Id := Parent_Subp;
12252 while Present (Overridden_Operation (E)) loop
12253 E := Ultimate_Alias (Overridden_Operation (E));
12256 Parent_Overrides_Interface_Primitive :=
12257 Is_Dispatching_Operation (E)
12258 and then Present (Find_Dispatching_Type (E))
12259 and then Is_Interface (Find_Dispatching_Type (E));
12263 -- Check whether the inherited subprogram is a private operation that
12264 -- should be inherited but not yet made visible. Such subprograms can
12265 -- become visible at a later point (e.g., the private part of a public
12266 -- child unit) via Declare_Inherited_Private_Subprograms. If the
12267 -- following predicate is true, then this is not such a private
12268 -- operation and the subprogram simply inherits the name of the parent
12269 -- subprogram. Note the special check for the names of controlled
12270 -- operations, which are currently exempted from being inherited with
12271 -- a hidden name because they must be findable for generation of
12272 -- implicit run-time calls.
12274 if not Is_Hidden (Parent_Subp)
12275 or else Is_Internal (Parent_Subp)
12276 or else Is_Private_Overriding
12277 or else Is_Internal_Name (Chars (Parent_Subp))
12278 or else Chars (Parent_Subp) = Name_Initialize
12279 or else Chars (Parent_Subp) = Name_Adjust
12280 or else Chars (Parent_Subp) = Name_Finalize
12284 -- An inherited dispatching equality will be overridden by an internally
12285 -- generated one, or by an explicit one, so preserve its name and thus
12286 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
12287 -- private operation it may become invisible if the full view has
12288 -- progenitors, and the dispatch table will be malformed.
12289 -- We check that the type is limited to handle the anomalous declaration
12290 -- of Limited_Controlled, which is derived from a non-limited type, and
12291 -- which is handled specially elsewhere as well.
12293 elsif Chars (Parent_Subp) = Name_Op_Eq
12294 and then Is_Dispatching_Operation (Parent_Subp)
12295 and then Etype (Parent_Subp) = Standard_Boolean
12296 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
12298 Etype (First_Formal (Parent_Subp)) =
12299 Etype (Next_Formal (First_Formal (Parent_Subp)))
12303 -- If parent is hidden, this can be a regular derivation if the
12304 -- parent is immediately visible in a non-instantiating context,
12305 -- or if we are in the private part of an instance. This test
12306 -- should still be refined ???
12308 -- The test for In_Instance_Not_Visible avoids inheriting the derived
12309 -- operation as a non-visible operation in cases where the parent
12310 -- subprogram might not be visible now, but was visible within the
12311 -- original generic, so it would be wrong to make the inherited
12312 -- subprogram non-visible now. (Not clear if this test is fully
12313 -- correct; are there any cases where we should declare the inherited
12314 -- operation as not visible to avoid it being overridden, e.g., when
12315 -- the parent type is a generic actual with private primitives ???)
12317 -- (they should be treated the same as other private inherited
12318 -- subprograms, but it's not clear how to do this cleanly). ???
12320 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
12321 and then Is_Immediately_Visible (Parent_Subp)
12322 and then not In_Instance)
12323 or else In_Instance_Not_Visible
12327 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
12328 -- overrides an interface primitive because interface primitives
12329 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
12331 elsif Parent_Overrides_Interface_Primitive then
12334 -- Otherwise, the type is inheriting a private operation, so enter
12335 -- it with a special name so it can't be overridden.
12338 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
12341 Set_Parent (New_Subp, Parent (Derived_Type));
12343 if Present (Actual_Subp) then
12344 Replace_Type (Actual_Subp, New_Subp);
12346 Replace_Type (Parent_Subp, New_Subp);
12349 Conditional_Delay (New_Subp, Parent_Subp);
12351 -- If we are creating a renaming for a primitive operation of an
12352 -- actual of a generic derived type, we must examine the signature
12353 -- of the actual primitive, not that of the generic formal, which for
12354 -- example may be an interface. However the name and initial value
12355 -- of the inherited operation are those of the formal primitive.
12357 Formal := First_Formal (Parent_Subp);
12359 if Present (Actual_Subp) then
12360 Formal_Of_Actual := First_Formal (Actual_Subp);
12362 Formal_Of_Actual := Empty;
12365 while Present (Formal) loop
12366 New_Formal := New_Copy (Formal);
12368 -- Normally we do not go copying parents, but in the case of
12369 -- formals, we need to link up to the declaration (which is the
12370 -- parameter specification), and it is fine to link up to the
12371 -- original formal's parameter specification in this case.
12373 Set_Parent (New_Formal, Parent (Formal));
12374 Append_Entity (New_Formal, New_Subp);
12376 if Present (Formal_Of_Actual) then
12377 Replace_Type (Formal_Of_Actual, New_Formal);
12378 Next_Formal (Formal_Of_Actual);
12380 Replace_Type (Formal, New_Formal);
12383 Next_Formal (Formal);
12386 -- If this derivation corresponds to a tagged generic actual, then
12387 -- primitive operations rename those of the actual. Otherwise the
12388 -- primitive operations rename those of the parent type, If the parent
12389 -- renames an intrinsic operator, so does the new subprogram. We except
12390 -- concatenation, which is always properly typed, and does not get
12391 -- expanded as other intrinsic operations.
12393 if No (Actual_Subp) then
12394 if Is_Intrinsic_Subprogram (Parent_Subp) then
12395 Set_Is_Intrinsic_Subprogram (New_Subp);
12397 if Present (Alias (Parent_Subp))
12398 and then Chars (Parent_Subp) /= Name_Op_Concat
12400 Set_Alias (New_Subp, Alias (Parent_Subp));
12402 Set_Alias (New_Subp, Parent_Subp);
12406 Set_Alias (New_Subp, Parent_Subp);
12410 Set_Alias (New_Subp, Actual_Subp);
12413 -- Derived subprograms of a tagged type must inherit the convention
12414 -- of the parent subprogram (a requirement of AI-117). Derived
12415 -- subprograms of untagged types simply get convention Ada by default.
12417 if Is_Tagged_Type (Derived_Type) then
12418 Set_Convention (New_Subp, Convention (Parent_Subp));
12421 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
12422 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
12424 if Ekind (Parent_Subp) = E_Procedure then
12425 Set_Is_Valued_Procedure
12426 (New_Subp, Is_Valued_Procedure (Parent_Subp));
12429 -- No_Return must be inherited properly. If this is overridden in the
12430 -- case of a dispatching operation, then a check is made in Sem_Disp
12431 -- that the overriding operation is also No_Return (no such check is
12432 -- required for the case of non-dispatching operation.
12434 Set_No_Return (New_Subp, No_Return (Parent_Subp));
12436 -- A derived function with a controlling result is abstract. If the
12437 -- Derived_Type is a nonabstract formal generic derived type, then
12438 -- inherited operations are not abstract: the required check is done at
12439 -- instantiation time. If the derivation is for a generic actual, the
12440 -- function is not abstract unless the actual is.
12442 if Is_Generic_Type (Derived_Type)
12443 and then not Is_Abstract_Type (Derived_Type)
12447 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
12448 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
12450 elsif Ada_Version >= Ada_05
12451 and then (Is_Abstract_Subprogram (Alias (New_Subp))
12452 or else (Is_Tagged_Type (Derived_Type)
12453 and then Etype (New_Subp) = Derived_Type
12454 and then not Is_Null_Extension (Derived_Type))
12455 or else (Is_Tagged_Type (Derived_Type)
12456 and then Ekind (Etype (New_Subp)) =
12457 E_Anonymous_Access_Type
12458 and then Designated_Type (Etype (New_Subp)) =
12460 and then not Is_Null_Extension (Derived_Type)))
12461 and then No (Actual_Subp)
12463 if not Is_Tagged_Type (Derived_Type)
12464 or else Is_Abstract_Type (Derived_Type)
12465 or else Is_Abstract_Subprogram (Alias (New_Subp))
12467 Set_Is_Abstract_Subprogram (New_Subp);
12469 Set_Requires_Overriding (New_Subp);
12472 elsif Ada_Version < Ada_05
12473 and then (Is_Abstract_Subprogram (Alias (New_Subp))
12474 or else (Is_Tagged_Type (Derived_Type)
12475 and then Etype (New_Subp) = Derived_Type
12476 and then No (Actual_Subp)))
12478 Set_Is_Abstract_Subprogram (New_Subp);
12480 -- Finally, if the parent type is abstract we must verify that all
12481 -- inherited operations are either non-abstract or overridden, or that
12482 -- the derived type itself is abstract (this check is performed at the
12483 -- end of a package declaration, in Check_Abstract_Overriding). A
12484 -- private overriding in the parent type will not be visible in the
12485 -- derivation if we are not in an inner package or in a child unit of
12486 -- the parent type, in which case the abstractness of the inherited
12487 -- operation is carried to the new subprogram.
12489 elsif Is_Abstract_Type (Parent_Type)
12490 and then not In_Open_Scopes (Scope (Parent_Type))
12491 and then Is_Private_Overriding
12492 and then Is_Abstract_Subprogram (Visible_Subp)
12494 if No (Actual_Subp) then
12495 Set_Alias (New_Subp, Visible_Subp);
12496 Set_Is_Abstract_Subprogram
12499 -- If this is a derivation for an instance of a formal derived
12500 -- type, abstractness comes from the primitive operation of the
12501 -- actual, not from the operation inherited from the ancestor.
12503 Set_Is_Abstract_Subprogram
12504 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
12508 New_Overloaded_Entity (New_Subp, Derived_Type);
12510 -- Check for case of a derived subprogram for the instantiation of a
12511 -- formal derived tagged type, if so mark the subprogram as dispatching
12512 -- and inherit the dispatching attributes of the parent subprogram. The
12513 -- derived subprogram is effectively renaming of the actual subprogram,
12514 -- so it needs to have the same attributes as the actual.
12516 if Present (Actual_Subp)
12517 and then Is_Dispatching_Operation (Parent_Subp)
12519 Set_Is_Dispatching_Operation (New_Subp);
12521 if Present (DTC_Entity (Parent_Subp)) then
12522 Set_DTC_Entity (New_Subp, DTC_Entity (Parent_Subp));
12523 Set_DT_Position (New_Subp, DT_Position (Parent_Subp));
12527 -- Indicate that a derived subprogram does not require a body and that
12528 -- it does not require processing of default expressions.
12530 Set_Has_Completion (New_Subp);
12531 Set_Default_Expressions_Processed (New_Subp);
12533 if Ekind (New_Subp) = E_Function then
12534 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
12536 end Derive_Subprogram;
12538 ------------------------
12539 -- Derive_Subprograms --
12540 ------------------------
12542 procedure Derive_Subprograms
12543 (Parent_Type : Entity_Id;
12544 Derived_Type : Entity_Id;
12545 Generic_Actual : Entity_Id := Empty)
12547 Op_List : constant Elist_Id :=
12548 Collect_Primitive_Operations (Parent_Type);
12550 function Check_Derived_Type return Boolean;
12551 -- Check that all primitive inherited from Parent_Type are found in
12552 -- the list of primitives of Derived_Type exactly in the same order.
12554 function Check_Derived_Type return Boolean is
12558 New_Subp : Entity_Id;
12563 -- Traverse list of entities in the current scope searching for
12564 -- an incomplete type whose full-view is derived type
12566 E := First_Entity (Scope (Derived_Type));
12568 and then E /= Derived_Type
12570 if Ekind (E) = E_Incomplete_Type
12571 and then Present (Full_View (E))
12572 and then Full_View (E) = Derived_Type
12574 -- Disable this test if Derived_Type completes an incomplete
12575 -- type because in such case more primitives can be added
12576 -- later to the list of primitives of Derived_Type by routine
12577 -- Process_Incomplete_Dependents
12582 E := Next_Entity (E);
12585 List := Collect_Primitive_Operations (Derived_Type);
12586 Elmt := First_Elmt (List);
12588 Op_Elmt := First_Elmt (Op_List);
12589 while Present (Op_Elmt) loop
12590 Subp := Node (Op_Elmt);
12591 New_Subp := Node (Elmt);
12593 -- At this early stage Derived_Type has no entities with attribute
12594 -- Interface_Alias. In addition, such primitives are always
12595 -- located at the end of the list of primitives of Parent_Type.
12596 -- Therefore, if found we can safely stop processing pending
12599 exit when Present (Interface_Alias (Subp));
12601 -- Handle hidden entities
12603 if not Is_Predefined_Dispatching_Operation (Subp)
12604 and then Is_Hidden (Subp)
12606 if Present (New_Subp)
12607 and then Primitive_Names_Match (Subp, New_Subp)
12613 if not Present (New_Subp)
12614 or else Ekind (Subp) /= Ekind (New_Subp)
12615 or else not Primitive_Names_Match (Subp, New_Subp)
12623 Next_Elmt (Op_Elmt);
12627 end Check_Derived_Type;
12631 Alias_Subp : Entity_Id;
12632 Act_List : Elist_Id;
12633 Act_Elmt : Elmt_Id := No_Elmt;
12634 Act_Subp : Entity_Id := Empty;
12636 Need_Search : Boolean := False;
12637 New_Subp : Entity_Id := Empty;
12638 Parent_Base : Entity_Id;
12641 -- Start of processing for Derive_Subprograms
12644 if Ekind (Parent_Type) = E_Record_Type_With_Private
12645 and then Has_Discriminants (Parent_Type)
12646 and then Present (Full_View (Parent_Type))
12648 Parent_Base := Full_View (Parent_Type);
12650 Parent_Base := Parent_Type;
12653 if Present (Generic_Actual) then
12654 Act_List := Collect_Primitive_Operations (Generic_Actual);
12655 Act_Elmt := First_Elmt (Act_List);
12658 -- Derive primitives inherited from the parent. Note that if the generic
12659 -- actual is present, this is not really a type derivation, it is a
12660 -- completion within an instance.
12662 -- Case 1: Derived_Type does not implement interfaces
12664 if not Is_Tagged_Type (Derived_Type)
12665 or else (not Has_Interfaces (Derived_Type)
12666 and then not (Present (Generic_Actual)
12668 Has_Interfaces (Generic_Actual)))
12670 Elmt := First_Elmt (Op_List);
12671 while Present (Elmt) loop
12672 Subp := Node (Elmt);
12674 -- Literals are derived earlier in the process of building the
12675 -- derived type, and are skipped here.
12677 if Ekind (Subp) = E_Enumeration_Literal then
12680 -- The actual is a direct descendant and the common primitive
12681 -- operations appear in the same order.
12683 -- If the generic parent type is present, the derived type is an
12684 -- instance of a formal derived type, and within the instance its
12685 -- operations are those of the actual. We derive from the formal
12686 -- type but make the inherited operations aliases of the
12687 -- corresponding operations of the actual.
12691 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
12693 if Present (Act_Elmt) then
12694 Next_Elmt (Act_Elmt);
12701 -- Case 2: Derived_Type implements interfaces
12704 -- If the parent type has no predefined primitives we remove
12705 -- predefined primitives from the list of primitives of generic
12706 -- actual to simplify the complexity of this algorithm.
12708 if Present (Generic_Actual) then
12710 Has_Predefined_Primitives : Boolean := False;
12713 -- Check if the parent type has predefined primitives
12715 Elmt := First_Elmt (Op_List);
12716 while Present (Elmt) loop
12717 Subp := Node (Elmt);
12719 if Is_Predefined_Dispatching_Operation (Subp)
12720 and then not Comes_From_Source (Ultimate_Alias (Subp))
12722 Has_Predefined_Primitives := True;
12729 -- Remove predefined primitives of Generic_Actual. We must use
12730 -- an auxiliary list because in case of tagged types the value
12731 -- returned by Collect_Primitive_Operations is the value stored
12732 -- in its Primitive_Operations attribute (and we don't want to
12733 -- modify its current contents).
12735 if not Has_Predefined_Primitives then
12737 Aux_List : constant Elist_Id := New_Elmt_List;
12740 Elmt := First_Elmt (Act_List);
12741 while Present (Elmt) loop
12742 Subp := Node (Elmt);
12744 if not Is_Predefined_Dispatching_Operation (Subp)
12745 or else Comes_From_Source (Subp)
12747 Append_Elmt (Subp, Aux_List);
12753 Act_List := Aux_List;
12757 Act_Elmt := First_Elmt (Act_List);
12758 Act_Subp := Node (Act_Elmt);
12762 -- Stage 1: If the generic actual is not present we derive the
12763 -- primitives inherited from the parent type. If the generic parent
12764 -- type is present, the derived type is an instance of a formal
12765 -- derived type, and within the instance its operations are those of
12766 -- the actual. We derive from the formal type but make the inherited
12767 -- operations aliases of the corresponding operations of the actual.
12769 Elmt := First_Elmt (Op_List);
12770 while Present (Elmt) loop
12771 Subp := Node (Elmt);
12772 Alias_Subp := Ultimate_Alias (Subp);
12774 -- At this early stage Derived_Type has no entities with attribute
12775 -- Interface_Alias. In addition, such primitives are always
12776 -- located at the end of the list of primitives of Parent_Type.
12777 -- Therefore, if found we can safely stop processing pending
12780 exit when Present (Interface_Alias (Subp));
12782 -- If the generic actual is present find the corresponding
12783 -- operation in the generic actual. If the parent type is a
12784 -- direct ancestor of the derived type then, even if it is an
12785 -- interface, the operations are inherited from the primary
12786 -- dispatch table and are in the proper order. If we detect here
12787 -- that primitives are not in the same order we traverse the list
12788 -- of primitive operations of the actual to find the one that
12789 -- implements the interface primitive.
12793 (Present (Generic_Actual)
12794 and then Present (Act_Subp)
12795 and then not Primitive_Names_Match (Subp, Act_Subp))
12797 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual));
12798 pragma Assert (Is_Interface (Parent_Base));
12800 -- Remember that we need searching for all the pending
12803 Need_Search := True;
12805 -- Handle entities associated with interface primitives
12807 if Present (Alias (Subp))
12808 and then Is_Interface (Find_Dispatching_Type (Alias (Subp)))
12809 and then not Is_Predefined_Dispatching_Operation (Subp)
12812 Find_Primitive_Covering_Interface
12813 (Tagged_Type => Generic_Actual,
12814 Iface_Prim => Subp);
12816 -- Handle predefined primitives plus the rest of user-defined
12820 Act_Elmt := First_Elmt (Act_List);
12821 while Present (Act_Elmt) loop
12822 Act_Subp := Node (Act_Elmt);
12824 exit when Primitive_Names_Match (Subp, Act_Subp)
12825 and then Type_Conformant (Subp, Act_Subp,
12826 Skip_Controlling_Formals => True)
12827 and then No (Interface_Alias (Act_Subp));
12829 Next_Elmt (Act_Elmt);
12834 -- Case 1: If the parent is a limited interface then it has the
12835 -- predefined primitives of synchronized interfaces. However, the
12836 -- actual type may be a non-limited type and hence it does not
12837 -- have such primitives.
12839 if Present (Generic_Actual)
12840 and then not Present (Act_Subp)
12841 and then Is_Limited_Interface (Parent_Base)
12842 and then Is_Predefined_Interface_Primitive (Subp)
12846 -- Case 2: Inherit entities associated with interfaces that
12847 -- were not covered by the parent type. We exclude here null
12848 -- interface primitives because they do not need special
12851 elsif Present (Alias (Subp))
12852 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
12854 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
12855 and then Null_Present (Parent (Alias_Subp)))
12858 (New_Subp => New_Subp,
12859 Parent_Subp => Alias_Subp,
12860 Derived_Type => Derived_Type,
12861 Parent_Type => Find_Dispatching_Type (Alias_Subp),
12862 Actual_Subp => Act_Subp);
12864 if No (Generic_Actual) then
12865 Set_Alias (New_Subp, Subp);
12868 -- Case 3: Common derivation
12872 (New_Subp => New_Subp,
12873 Parent_Subp => Subp,
12874 Derived_Type => Derived_Type,
12875 Parent_Type => Parent_Base,
12876 Actual_Subp => Act_Subp);
12879 -- No need to update Act_Elm if we must search for the
12880 -- corresponding operation in the generic actual
12883 and then Present (Act_Elmt)
12885 Next_Elmt (Act_Elmt);
12886 Act_Subp := Node (Act_Elmt);
12892 -- Inherit additional operations from progenitors. If the derived
12893 -- type is a generic actual, there are not new primitive operations
12894 -- for the type because it has those of the actual, and therefore
12895 -- nothing needs to be done. The renamings generated above are not
12896 -- primitive operations, and their purpose is simply to make the
12897 -- proper operations visible within an instantiation.
12899 if No (Generic_Actual) then
12900 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
12904 -- Final check: Direct descendants must have their primitives in the
12905 -- same order. We exclude from this test non-tagged types and instances
12906 -- of formal derived types. We skip this test if we have already
12907 -- reported serious errors in the sources.
12909 pragma Assert (not Is_Tagged_Type (Derived_Type)
12910 or else Present (Generic_Actual)
12911 or else Serious_Errors_Detected > 0
12912 or else Check_Derived_Type);
12913 end Derive_Subprograms;
12915 --------------------------------
12916 -- Derived_Standard_Character --
12917 --------------------------------
12919 procedure Derived_Standard_Character
12921 Parent_Type : Entity_Id;
12922 Derived_Type : Entity_Id)
12924 Loc : constant Source_Ptr := Sloc (N);
12925 Def : constant Node_Id := Type_Definition (N);
12926 Indic : constant Node_Id := Subtype_Indication (Def);
12927 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
12928 Implicit_Base : constant Entity_Id :=
12930 (E_Enumeration_Type, N, Derived_Type, 'B');
12936 Discard_Node (Process_Subtype (Indic, N));
12938 Set_Etype (Implicit_Base, Parent_Base);
12939 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
12940 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
12942 Set_Is_Character_Type (Implicit_Base, True);
12943 Set_Has_Delayed_Freeze (Implicit_Base);
12945 -- The bounds of the implicit base are the bounds of the parent base.
12946 -- Note that their type is the parent base.
12948 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
12949 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
12951 Set_Scalar_Range (Implicit_Base,
12954 High_Bound => Hi));
12956 Conditional_Delay (Derived_Type, Parent_Type);
12958 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
12959 Set_Etype (Derived_Type, Implicit_Base);
12960 Set_Size_Info (Derived_Type, Parent_Type);
12962 if Unknown_RM_Size (Derived_Type) then
12963 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
12966 Set_Is_Character_Type (Derived_Type, True);
12968 if Nkind (Indic) /= N_Subtype_Indication then
12970 -- If no explicit constraint, the bounds are those
12971 -- of the parent type.
12973 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
12974 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
12975 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
12978 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
12980 -- Because the implicit base is used in the conversion of the bounds, we
12981 -- have to freeze it now. This is similar to what is done for numeric
12982 -- types, and it equally suspicious, but otherwise a non-static bound
12983 -- will have a reference to an unfrozen type, which is rejected by Gigi
12984 -- (???). This requires specific care for definition of stream
12985 -- attributes. For details, see comments at the end of
12986 -- Build_Derived_Numeric_Type.
12988 Freeze_Before (N, Implicit_Base);
12989 end Derived_Standard_Character;
12991 ------------------------------
12992 -- Derived_Type_Declaration --
12993 ------------------------------
12995 procedure Derived_Type_Declaration
12998 Is_Completion : Boolean)
13000 Parent_Type : Entity_Id;
13002 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
13003 -- Check whether the parent type is a generic formal, or derives
13004 -- directly or indirectly from one.
13006 ------------------------
13007 -- Comes_From_Generic --
13008 ------------------------
13010 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
13012 if Is_Generic_Type (Typ) then
13015 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
13018 elsif Is_Private_Type (Typ)
13019 and then Present (Full_View (Typ))
13020 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
13024 elsif Is_Generic_Actual_Type (Typ) then
13030 end Comes_From_Generic;
13034 Def : constant Node_Id := Type_Definition (N);
13035 Iface_Def : Node_Id;
13036 Indic : constant Node_Id := Subtype_Indication (Def);
13037 Extension : constant Node_Id := Record_Extension_Part (Def);
13038 Parent_Node : Node_Id;
13039 Parent_Scope : Entity_Id;
13042 -- Start of processing for Derived_Type_Declaration
13045 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
13047 -- Ada 2005 (AI-251): In case of interface derivation check that the
13048 -- parent is also an interface.
13050 if Interface_Present (Def) then
13051 if not Is_Interface (Parent_Type) then
13052 Diagnose_Interface (Indic, Parent_Type);
13055 Parent_Node := Parent (Base_Type (Parent_Type));
13056 Iface_Def := Type_Definition (Parent_Node);
13058 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
13059 -- other limited interfaces.
13061 if Limited_Present (Def) then
13062 if Limited_Present (Iface_Def) then
13065 elsif Protected_Present (Iface_Def) then
13067 ("descendant of& must be declared"
13068 & " as a protected interface",
13071 elsif Synchronized_Present (Iface_Def) then
13073 ("descendant of& must be declared"
13074 & " as a synchronized interface",
13077 elsif Task_Present (Iface_Def) then
13079 ("descendant of& must be declared as a task interface",
13084 ("(Ada 2005) limited interface cannot "
13085 & "inherit from non-limited interface", Indic);
13088 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
13089 -- from non-limited or limited interfaces.
13091 elsif not Protected_Present (Def)
13092 and then not Synchronized_Present (Def)
13093 and then not Task_Present (Def)
13095 if Limited_Present (Iface_Def) then
13098 elsif Protected_Present (Iface_Def) then
13100 ("descendant of& must be declared"
13101 & " as a protected interface",
13104 elsif Synchronized_Present (Iface_Def) then
13106 ("descendant of& must be declared"
13107 & " as a synchronized interface",
13110 elsif Task_Present (Iface_Def) then
13112 ("descendant of& must be declared as a task interface",
13121 if Is_Tagged_Type (Parent_Type)
13122 and then Is_Concurrent_Type (Parent_Type)
13123 and then not Is_Interface (Parent_Type)
13126 ("parent type of a record extension cannot be "
13127 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
13128 Set_Etype (T, Any_Type);
13132 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
13135 if Is_Tagged_Type (Parent_Type)
13136 and then Is_Non_Empty_List (Interface_List (Def))
13143 Intf := First (Interface_List (Def));
13144 while Present (Intf) loop
13145 T := Find_Type_Of_Subtype_Indic (Intf);
13147 if not Is_Interface (T) then
13148 Diagnose_Interface (Intf, T);
13150 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
13151 -- a limited type from having a nonlimited progenitor.
13153 elsif (Limited_Present (Def)
13154 or else (not Is_Interface (Parent_Type)
13155 and then Is_Limited_Type (Parent_Type)))
13156 and then not Is_Limited_Interface (T)
13159 ("progenitor interface& of limited type must be limited",
13168 if Parent_Type = Any_Type
13169 or else Etype (Parent_Type) = Any_Type
13170 or else (Is_Class_Wide_Type (Parent_Type)
13171 and then Etype (Parent_Type) = T)
13173 -- If Parent_Type is undefined or illegal, make new type into a
13174 -- subtype of Any_Type, and set a few attributes to prevent cascaded
13175 -- errors. If this is a self-definition, emit error now.
13178 or else T = Etype (Parent_Type)
13180 Error_Msg_N ("type cannot be used in its own definition", Indic);
13183 Set_Ekind (T, Ekind (Parent_Type));
13184 Set_Etype (T, Any_Type);
13185 Set_Scalar_Range (T, Scalar_Range (Any_Type));
13187 if Is_Tagged_Type (T) then
13188 Set_Primitive_Operations (T, New_Elmt_List);
13194 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
13195 -- an interface is special because the list of interfaces in the full
13196 -- view can be given in any order. For example:
13198 -- type A is interface;
13199 -- type B is interface and A;
13200 -- type D is new B with private;
13202 -- type D is new A and B with null record; -- 1 --
13204 -- In this case we perform the following transformation of -1-:
13206 -- type D is new B and A with null record;
13208 -- If the parent of the full-view covers the parent of the partial-view
13209 -- we have two possible cases:
13211 -- 1) They have the same parent
13212 -- 2) The parent of the full-view implements some further interfaces
13214 -- In both cases we do not need to perform the transformation. In the
13215 -- first case the source program is correct and the transformation is
13216 -- not needed; in the second case the source program does not fulfill
13217 -- the no-hidden interfaces rule (AI-396) and the error will be reported
13220 -- This transformation not only simplifies the rest of the analysis of
13221 -- this type declaration but also simplifies the correct generation of
13222 -- the object layout to the expander.
13224 if In_Private_Part (Current_Scope)
13225 and then Is_Interface (Parent_Type)
13229 Partial_View : Entity_Id;
13230 Partial_View_Parent : Entity_Id;
13231 New_Iface : Node_Id;
13234 -- Look for the associated private type declaration
13236 Partial_View := First_Entity (Current_Scope);
13238 exit when No (Partial_View)
13239 or else (Has_Private_Declaration (Partial_View)
13240 and then Full_View (Partial_View) = T);
13242 Next_Entity (Partial_View);
13245 -- If the partial view was not found then the source code has
13246 -- errors and the transformation is not needed.
13248 if Present (Partial_View) then
13249 Partial_View_Parent := Etype (Partial_View);
13251 -- If the parent of the full-view covers the parent of the
13252 -- partial-view we have nothing else to do.
13254 if Interface_Present_In_Ancestor
13255 (Parent_Type, Partial_View_Parent)
13259 -- Traverse the list of interfaces of the full-view to look
13260 -- for the parent of the partial-view and perform the tree
13264 Iface := First (Interface_List (Def));
13265 while Present (Iface) loop
13266 if Etype (Iface) = Etype (Partial_View) then
13267 Rewrite (Subtype_Indication (Def),
13268 New_Copy (Subtype_Indication
13269 (Parent (Partial_View))));
13271 New_Iface := Make_Identifier (Sloc (N),
13272 Chars (Parent_Type));
13273 Append (New_Iface, Interface_List (Def));
13275 -- Analyze the transformed code
13277 Derived_Type_Declaration (T, N, Is_Completion);
13288 -- Only composite types other than array types are allowed to have
13291 if Present (Discriminant_Specifications (N))
13292 and then (Is_Elementary_Type (Parent_Type)
13293 or else Is_Array_Type (Parent_Type))
13294 and then not Error_Posted (N)
13297 ("elementary or array type cannot have discriminants",
13298 Defining_Identifier (First (Discriminant_Specifications (N))));
13299 Set_Has_Discriminants (T, False);
13302 -- In Ada 83, a derived type defined in a package specification cannot
13303 -- be used for further derivation until the end of its visible part.
13304 -- Note that derivation in the private part of the package is allowed.
13306 if Ada_Version = Ada_83
13307 and then Is_Derived_Type (Parent_Type)
13308 and then In_Visible_Part (Scope (Parent_Type))
13310 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
13312 ("(Ada 83): premature use of type for derivation", Indic);
13316 -- Check for early use of incomplete or private type
13318 if Ekind (Parent_Type) = E_Void
13319 or else Ekind (Parent_Type) = E_Incomplete_Type
13321 Error_Msg_N ("premature derivation of incomplete type", Indic);
13324 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
13325 and then not Comes_From_Generic (Parent_Type))
13326 or else Has_Private_Component (Parent_Type)
13328 -- The ancestor type of a formal type can be incomplete, in which
13329 -- case only the operations of the partial view are available in
13330 -- the generic. Subsequent checks may be required when the full
13331 -- view is analyzed, to verify that derivation from a tagged type
13332 -- has an extension.
13334 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
13337 elsif No (Underlying_Type (Parent_Type))
13338 or else Has_Private_Component (Parent_Type)
13341 ("premature derivation of derived or private type", Indic);
13343 -- Flag the type itself as being in error, this prevents some
13344 -- nasty problems with subsequent uses of the malformed type.
13346 Set_Error_Posted (T);
13348 -- Check that within the immediate scope of an untagged partial
13349 -- view it's illegal to derive from the partial view if the
13350 -- full view is tagged. (7.3(7))
13352 -- We verify that the Parent_Type is a partial view by checking
13353 -- that it is not a Full_Type_Declaration (i.e. a private type or
13354 -- private extension declaration), to distinguish a partial view
13355 -- from a derivation from a private type which also appears as
13358 elsif Present (Full_View (Parent_Type))
13359 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
13360 and then not Is_Tagged_Type (Parent_Type)
13361 and then Is_Tagged_Type (Full_View (Parent_Type))
13363 Parent_Scope := Scope (T);
13364 while Present (Parent_Scope)
13365 and then Parent_Scope /= Standard_Standard
13367 if Parent_Scope = Scope (Parent_Type) then
13369 ("premature derivation from type with tagged full view",
13373 Parent_Scope := Scope (Parent_Scope);
13378 -- Check that form of derivation is appropriate
13380 Taggd := Is_Tagged_Type (Parent_Type);
13382 -- Perhaps the parent type should be changed to the class-wide type's
13383 -- specific type in this case to prevent cascading errors ???
13385 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
13386 Error_Msg_N ("parent type must not be a class-wide type", Indic);
13390 if Present (Extension) and then not Taggd then
13392 ("type derived from untagged type cannot have extension", Indic);
13394 elsif No (Extension) and then Taggd then
13396 -- If this declaration is within a private part (or body) of a
13397 -- generic instantiation then the derivation is allowed (the parent
13398 -- type can only appear tagged in this case if it's a generic actual
13399 -- type, since it would otherwise have been rejected in the analysis
13400 -- of the generic template).
13402 if not Is_Generic_Actual_Type (Parent_Type)
13403 or else In_Visible_Part (Scope (Parent_Type))
13406 ("type derived from tagged type must have extension", Indic);
13410 -- AI-443: Synchronized formal derived types require a private
13411 -- extension. There is no point in checking the ancestor type or
13412 -- the progenitors since the construct is wrong to begin with.
13414 if Ada_Version >= Ada_05
13415 and then Is_Generic_Type (T)
13416 and then Present (Original_Node (N))
13419 Decl : constant Node_Id := Original_Node (N);
13422 if Nkind (Decl) = N_Formal_Type_Declaration
13423 and then Nkind (Formal_Type_Definition (Decl)) =
13424 N_Formal_Derived_Type_Definition
13425 and then Synchronized_Present (Formal_Type_Definition (Decl))
13426 and then No (Extension)
13428 -- Avoid emitting a duplicate error message
13430 and then not Error_Posted (Indic)
13433 ("synchronized derived type must have extension", N);
13438 if Null_Exclusion_Present (Def)
13439 and then not Is_Access_Type (Parent_Type)
13441 Error_Msg_N ("null exclusion can only apply to an access type", N);
13444 -- Avoid deriving parent primitives of underlying record views
13446 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
13447 Derive_Subps => not Is_Underlying_Record_View (T));
13449 -- AI-419: The parent type of an explicitly limited derived type must
13450 -- be a limited type or a limited interface.
13452 if Limited_Present (Def) then
13453 Set_Is_Limited_Record (T);
13455 if Is_Interface (T) then
13456 Set_Is_Limited_Interface (T);
13459 if not Is_Limited_Type (Parent_Type)
13461 (not Is_Interface (Parent_Type)
13462 or else not Is_Limited_Interface (Parent_Type))
13464 Error_Msg_NE ("parent type& of limited type must be limited",
13468 end Derived_Type_Declaration;
13470 ------------------------
13471 -- Diagnose_Interface --
13472 ------------------------
13474 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
13476 if not Is_Interface (E)
13477 and then E /= Any_Type
13479 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
13481 end Diagnose_Interface;
13483 ----------------------------------
13484 -- Enumeration_Type_Declaration --
13485 ----------------------------------
13487 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
13494 -- Create identifier node representing lower bound
13496 B_Node := New_Node (N_Identifier, Sloc (Def));
13497 L := First (Literals (Def));
13498 Set_Chars (B_Node, Chars (L));
13499 Set_Entity (B_Node, L);
13500 Set_Etype (B_Node, T);
13501 Set_Is_Static_Expression (B_Node, True);
13503 R_Node := New_Node (N_Range, Sloc (Def));
13504 Set_Low_Bound (R_Node, B_Node);
13506 Set_Ekind (T, E_Enumeration_Type);
13507 Set_First_Literal (T, L);
13509 Set_Is_Constrained (T);
13513 -- Loop through literals of enumeration type setting pos and rep values
13514 -- except that if the Ekind is already set, then it means the literal
13515 -- was already constructed (case of a derived type declaration and we
13516 -- should not disturb the Pos and Rep values.
13518 while Present (L) loop
13519 if Ekind (L) /= E_Enumeration_Literal then
13520 Set_Ekind (L, E_Enumeration_Literal);
13521 Set_Enumeration_Pos (L, Ev);
13522 Set_Enumeration_Rep (L, Ev);
13523 Set_Is_Known_Valid (L, True);
13527 New_Overloaded_Entity (L);
13528 Generate_Definition (L);
13529 Set_Convention (L, Convention_Intrinsic);
13531 if Nkind (L) = N_Defining_Character_Literal then
13532 Set_Is_Character_Type (T, True);
13539 -- Now create a node representing upper bound
13541 B_Node := New_Node (N_Identifier, Sloc (Def));
13542 Set_Chars (B_Node, Chars (Last (Literals (Def))));
13543 Set_Entity (B_Node, Last (Literals (Def)));
13544 Set_Etype (B_Node, T);
13545 Set_Is_Static_Expression (B_Node, True);
13547 Set_High_Bound (R_Node, B_Node);
13549 -- Initialize various fields of the type. Some of this information
13550 -- may be overwritten later through rep.clauses.
13552 Set_Scalar_Range (T, R_Node);
13553 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
13554 Set_Enum_Esize (T);
13555 Set_Enum_Pos_To_Rep (T, Empty);
13557 -- Set Discard_Names if configuration pragma set, or if there is
13558 -- a parameterless pragma in the current declarative region
13560 if Global_Discard_Names
13561 or else Discard_Names (Scope (T))
13563 Set_Discard_Names (T);
13566 -- Process end label if there is one
13568 if Present (Def) then
13569 Process_End_Label (Def, 'e', T);
13571 end Enumeration_Type_Declaration;
13573 ---------------------------------
13574 -- Expand_To_Stored_Constraint --
13575 ---------------------------------
13577 function Expand_To_Stored_Constraint
13579 Constraint : Elist_Id) return Elist_Id
13581 Explicitly_Discriminated_Type : Entity_Id;
13582 Expansion : Elist_Id;
13583 Discriminant : Entity_Id;
13585 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
13586 -- Find the nearest type that actually specifies discriminants
13588 ---------------------------------
13589 -- Type_With_Explicit_Discrims --
13590 ---------------------------------
13592 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
13593 Typ : constant E := Base_Type (Id);
13596 if Ekind (Typ) in Incomplete_Or_Private_Kind then
13597 if Present (Full_View (Typ)) then
13598 return Type_With_Explicit_Discrims (Full_View (Typ));
13602 if Has_Discriminants (Typ) then
13607 if Etype (Typ) = Typ then
13609 elsif Has_Discriminants (Typ) then
13612 return Type_With_Explicit_Discrims (Etype (Typ));
13615 end Type_With_Explicit_Discrims;
13617 -- Start of processing for Expand_To_Stored_Constraint
13621 or else Is_Empty_Elmt_List (Constraint)
13626 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
13628 if No (Explicitly_Discriminated_Type) then
13632 Expansion := New_Elmt_List;
13635 First_Stored_Discriminant (Explicitly_Discriminated_Type);
13636 while Present (Discriminant) loop
13638 Get_Discriminant_Value (
13639 Discriminant, Explicitly_Discriminated_Type, Constraint),
13641 Next_Stored_Discriminant (Discriminant);
13645 end Expand_To_Stored_Constraint;
13647 ---------------------------
13648 -- Find_Hidden_Interface --
13649 ---------------------------
13651 function Find_Hidden_Interface
13653 Dest : Elist_Id) return Entity_Id
13656 Iface_Elmt : Elmt_Id;
13659 if Present (Src) and then Present (Dest) then
13660 Iface_Elmt := First_Elmt (Src);
13661 while Present (Iface_Elmt) loop
13662 Iface := Node (Iface_Elmt);
13664 if Is_Interface (Iface)
13665 and then not Contain_Interface (Iface, Dest)
13670 Next_Elmt (Iface_Elmt);
13675 end Find_Hidden_Interface;
13677 --------------------
13678 -- Find_Type_Name --
13679 --------------------
13681 function Find_Type_Name (N : Node_Id) return Entity_Id is
13682 Id : constant Entity_Id := Defining_Identifier (N);
13684 New_Id : Entity_Id;
13685 Prev_Par : Node_Id;
13687 procedure Tag_Mismatch;
13688 -- Diagnose a tagged partial view whose full view is untagged.
13689 -- We post the message on the full view, with a reference to
13690 -- the previous partial view. The partial view can be private
13691 -- or incomplete, and these are handled in a different manner,
13692 -- so we determine the position of the error message from the
13693 -- respective slocs of both.
13699 procedure Tag_Mismatch is
13701 if Sloc (Prev) < Sloc (Id) then
13703 ("full declaration of } must be a tagged type ", Id, Prev);
13706 ("full declaration of } must be a tagged type ", Prev, Id);
13710 -- Start of processing for Find_Type_Name
13713 -- Find incomplete declaration, if one was given
13715 Prev := Current_Entity_In_Scope (Id);
13717 if Present (Prev) then
13719 -- Previous declaration exists. Error if not incomplete/private case
13720 -- except if previous declaration is implicit, etc. Enter_Name will
13721 -- emit error if appropriate.
13723 Prev_Par := Parent (Prev);
13725 if not Is_Incomplete_Or_Private_Type (Prev) then
13729 elsif not Nkind_In (N, N_Full_Type_Declaration,
13730 N_Task_Type_Declaration,
13731 N_Protected_Type_Declaration)
13733 -- Completion must be a full type declarations (RM 7.3(4))
13735 Error_Msg_Sloc := Sloc (Prev);
13736 Error_Msg_NE ("invalid completion of }", Id, Prev);
13738 -- Set scope of Id to avoid cascaded errors. Entity is never
13739 -- examined again, except when saving globals in generics.
13741 Set_Scope (Id, Current_Scope);
13744 -- If this is a repeated incomplete declaration, no further
13745 -- checks are possible.
13747 if Nkind (N) = N_Incomplete_Type_Declaration then
13751 -- Case of full declaration of incomplete type
13753 elsif Ekind (Prev) = E_Incomplete_Type then
13755 -- Indicate that the incomplete declaration has a matching full
13756 -- declaration. The defining occurrence of the incomplete
13757 -- declaration remains the visible one, and the procedure
13758 -- Get_Full_View dereferences it whenever the type is used.
13760 if Present (Full_View (Prev)) then
13761 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
13764 Set_Full_View (Prev, Id);
13765 Append_Entity (Id, Current_Scope);
13766 Set_Is_Public (Id, Is_Public (Prev));
13767 Set_Is_Internal (Id);
13770 -- Case of full declaration of private type
13773 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
13774 if Etype (Prev) /= Prev then
13776 -- Prev is a private subtype or a derived type, and needs
13779 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
13782 elsif Ekind (Prev) = E_Private_Type
13783 and then Nkind_In (N, N_Task_Type_Declaration,
13784 N_Protected_Type_Declaration)
13787 ("completion of nonlimited type cannot be limited", N);
13789 elsif Ekind (Prev) = E_Record_Type_With_Private
13790 and then Nkind_In (N, N_Task_Type_Declaration,
13791 N_Protected_Type_Declaration)
13793 if not Is_Limited_Record (Prev) then
13795 ("completion of nonlimited type cannot be limited", N);
13797 elsif No (Interface_List (N)) then
13799 ("completion of tagged private type must be tagged",
13803 elsif Nkind (N) = N_Full_Type_Declaration
13805 Nkind (Type_Definition (N)) = N_Record_Definition
13806 and then Interface_Present (Type_Definition (N))
13809 ("completion of private type cannot be an interface", N);
13812 -- Ada 2005 (AI-251): Private extension declaration of a task
13813 -- type or a protected type. This case arises when covering
13814 -- interface types.
13816 elsif Nkind_In (N, N_Task_Type_Declaration,
13817 N_Protected_Type_Declaration)
13821 elsif Nkind (N) /= N_Full_Type_Declaration
13822 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
13825 ("full view of private extension must be an extension", N);
13827 elsif not (Abstract_Present (Parent (Prev)))
13828 and then Abstract_Present (Type_Definition (N))
13831 ("full view of non-abstract extension cannot be abstract", N);
13834 if not In_Private_Part (Current_Scope) then
13836 ("declaration of full view must appear in private part", N);
13839 Copy_And_Swap (Prev, Id);
13840 Set_Has_Private_Declaration (Prev);
13841 Set_Has_Private_Declaration (Id);
13843 -- If no error, propagate freeze_node from private to full view.
13844 -- It may have been generated for an early operational item.
13846 if Present (Freeze_Node (Id))
13847 and then Serious_Errors_Detected = 0
13848 and then No (Full_View (Id))
13850 Set_Freeze_Node (Prev, Freeze_Node (Id));
13851 Set_Freeze_Node (Id, Empty);
13852 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
13855 Set_Full_View (Id, Prev);
13859 -- Verify that full declaration conforms to partial one
13861 if Is_Incomplete_Or_Private_Type (Prev)
13862 and then Present (Discriminant_Specifications (Prev_Par))
13864 if Present (Discriminant_Specifications (N)) then
13865 if Ekind (Prev) = E_Incomplete_Type then
13866 Check_Discriminant_Conformance (N, Prev, Prev);
13868 Check_Discriminant_Conformance (N, Prev, Id);
13873 ("missing discriminants in full type declaration", N);
13875 -- To avoid cascaded errors on subsequent use, share the
13876 -- discriminants of the partial view.
13878 Set_Discriminant_Specifications (N,
13879 Discriminant_Specifications (Prev_Par));
13883 -- A prior untagged partial view can have an associated class-wide
13884 -- type due to use of the class attribute, and in this case the full
13885 -- type must also be tagged. This Ada 95 usage is deprecated in favor
13886 -- of incomplete tagged declarations, but we check for it.
13889 and then (Is_Tagged_Type (Prev)
13890 or else Present (Class_Wide_Type (Prev)))
13892 -- The full declaration is either a tagged type (including
13893 -- a synchronized type that implements interfaces) or a
13894 -- type extension, otherwise this is an error.
13896 if Nkind_In (N, N_Task_Type_Declaration,
13897 N_Protected_Type_Declaration)
13899 if No (Interface_List (N))
13900 and then not Error_Posted (N)
13905 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
13907 -- Indicate that the previous declaration (tagged incomplete
13908 -- or private declaration) requires the same on the full one.
13910 if not Tagged_Present (Type_Definition (N)) then
13912 Set_Is_Tagged_Type (Id);
13913 Set_Primitive_Operations (Id, New_Elmt_List);
13916 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
13917 if No (Record_Extension_Part (Type_Definition (N))) then
13919 "full declaration of } must be a record extension",
13922 -- Set some attributes to produce a usable full view
13924 Set_Is_Tagged_Type (Id);
13925 Set_Primitive_Operations (Id, New_Elmt_List);
13936 -- New type declaration
13941 end Find_Type_Name;
13943 -------------------------
13944 -- Find_Type_Of_Object --
13945 -------------------------
13947 function Find_Type_Of_Object
13948 (Obj_Def : Node_Id;
13949 Related_Nod : Node_Id) return Entity_Id
13951 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
13952 P : Node_Id := Parent (Obj_Def);
13957 -- If the parent is a component_definition node we climb to the
13958 -- component_declaration node
13960 if Nkind (P) = N_Component_Definition then
13964 -- Case of an anonymous array subtype
13966 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
13967 N_Unconstrained_Array_Definition)
13970 Array_Type_Declaration (T, Obj_Def);
13972 -- Create an explicit subtype whenever possible
13974 elsif Nkind (P) /= N_Component_Declaration
13975 and then Def_Kind = N_Subtype_Indication
13977 -- Base name of subtype on object name, which will be unique in
13978 -- the current scope.
13980 -- If this is a duplicate declaration, return base type, to avoid
13981 -- generating duplicate anonymous types.
13983 if Error_Posted (P) then
13984 Analyze (Subtype_Mark (Obj_Def));
13985 return Entity (Subtype_Mark (Obj_Def));
13990 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
13992 T := Make_Defining_Identifier (Sloc (P), Nam);
13994 Insert_Action (Obj_Def,
13995 Make_Subtype_Declaration (Sloc (P),
13996 Defining_Identifier => T,
13997 Subtype_Indication => Relocate_Node (Obj_Def)));
13999 -- This subtype may need freezing, and this will not be done
14000 -- automatically if the object declaration is not in declarative
14001 -- part. Since this is an object declaration, the type cannot always
14002 -- be frozen here. Deferred constants do not freeze their type
14003 -- (which often enough will be private).
14005 if Nkind (P) = N_Object_Declaration
14006 and then Constant_Present (P)
14007 and then No (Expression (P))
14011 Insert_Actions (Obj_Def, Freeze_Entity (T, Sloc (P)));
14014 -- Ada 2005 AI-406: the object definition in an object declaration
14015 -- can be an access definition.
14017 elsif Def_Kind = N_Access_Definition then
14018 T := Access_Definition (Related_Nod, Obj_Def);
14019 Set_Is_Local_Anonymous_Access (T);
14021 -- Otherwise, the object definition is just a subtype_mark
14024 T := Process_Subtype (Obj_Def, Related_Nod);
14028 end Find_Type_Of_Object;
14030 --------------------------------
14031 -- Find_Type_Of_Subtype_Indic --
14032 --------------------------------
14034 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
14038 -- Case of subtype mark with a constraint
14040 if Nkind (S) = N_Subtype_Indication then
14041 Find_Type (Subtype_Mark (S));
14042 Typ := Entity (Subtype_Mark (S));
14045 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
14048 ("incorrect constraint for this kind of type", Constraint (S));
14049 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
14052 -- Otherwise we have a subtype mark without a constraint
14054 elsif Error_Posted (S) then
14055 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
14063 -- Check No_Wide_Characters restriction
14065 if Typ = Standard_Wide_Character
14066 or else Typ = Standard_Wide_Wide_Character
14067 or else Typ = Standard_Wide_String
14068 or else Typ = Standard_Wide_Wide_String
14070 Check_Restriction (No_Wide_Characters, S);
14074 end Find_Type_Of_Subtype_Indic;
14076 -------------------------------------
14077 -- Floating_Point_Type_Declaration --
14078 -------------------------------------
14080 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
14081 Digs : constant Node_Id := Digits_Expression (Def);
14083 Base_Typ : Entity_Id;
14084 Implicit_Base : Entity_Id;
14087 function Can_Derive_From (E : Entity_Id) return Boolean;
14088 -- Find if given digits value allows derivation from specified type
14090 ---------------------
14091 -- Can_Derive_From --
14092 ---------------------
14094 function Can_Derive_From (E : Entity_Id) return Boolean is
14095 Spec : constant Entity_Id := Real_Range_Specification (Def);
14098 if Digs_Val > Digits_Value (E) then
14102 if Present (Spec) then
14103 if Expr_Value_R (Type_Low_Bound (E)) >
14104 Expr_Value_R (Low_Bound (Spec))
14109 if Expr_Value_R (Type_High_Bound (E)) <
14110 Expr_Value_R (High_Bound (Spec))
14117 end Can_Derive_From;
14119 -- Start of processing for Floating_Point_Type_Declaration
14122 Check_Restriction (No_Floating_Point, Def);
14124 -- Create an implicit base type
14127 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
14129 -- Analyze and verify digits value
14131 Analyze_And_Resolve (Digs, Any_Integer);
14132 Check_Digits_Expression (Digs);
14133 Digs_Val := Expr_Value (Digs);
14135 -- Process possible range spec and find correct type to derive from
14137 Process_Real_Range_Specification (Def);
14139 if Can_Derive_From (Standard_Short_Float) then
14140 Base_Typ := Standard_Short_Float;
14141 elsif Can_Derive_From (Standard_Float) then
14142 Base_Typ := Standard_Float;
14143 elsif Can_Derive_From (Standard_Long_Float) then
14144 Base_Typ := Standard_Long_Float;
14145 elsif Can_Derive_From (Standard_Long_Long_Float) then
14146 Base_Typ := Standard_Long_Long_Float;
14148 -- If we can't derive from any existing type, use long_long_float
14149 -- and give appropriate message explaining the problem.
14152 Base_Typ := Standard_Long_Long_Float;
14154 if Digs_Val >= Digits_Value (Standard_Long_Long_Float) then
14155 Error_Msg_Uint_1 := Digits_Value (Standard_Long_Long_Float);
14156 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
14160 ("range too large for any predefined type",
14161 Real_Range_Specification (Def));
14165 -- If there are bounds given in the declaration use them as the bounds
14166 -- of the type, otherwise use the bounds of the predefined base type
14167 -- that was chosen based on the Digits value.
14169 if Present (Real_Range_Specification (Def)) then
14170 Set_Scalar_Range (T, Real_Range_Specification (Def));
14171 Set_Is_Constrained (T);
14173 -- The bounds of this range must be converted to machine numbers
14174 -- in accordance with RM 4.9(38).
14176 Bound := Type_Low_Bound (T);
14178 if Nkind (Bound) = N_Real_Literal then
14180 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
14181 Set_Is_Machine_Number (Bound);
14184 Bound := Type_High_Bound (T);
14186 if Nkind (Bound) = N_Real_Literal then
14188 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
14189 Set_Is_Machine_Number (Bound);
14193 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
14196 -- Complete definition of implicit base and declared first subtype
14198 Set_Etype (Implicit_Base, Base_Typ);
14200 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
14201 Set_Size_Info (Implicit_Base, (Base_Typ));
14202 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
14203 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
14204 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
14205 Set_Vax_Float (Implicit_Base, Vax_Float (Base_Typ));
14207 Set_Ekind (T, E_Floating_Point_Subtype);
14208 Set_Etype (T, Implicit_Base);
14210 Set_Size_Info (T, (Implicit_Base));
14211 Set_RM_Size (T, RM_Size (Implicit_Base));
14212 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
14213 Set_Digits_Value (T, Digs_Val);
14214 end Floating_Point_Type_Declaration;
14216 ----------------------------
14217 -- Get_Discriminant_Value --
14218 ----------------------------
14220 -- This is the situation:
14222 -- There is a non-derived type
14224 -- type T0 (Dx, Dy, Dz...)
14226 -- There are zero or more levels of derivation, with each derivation
14227 -- either purely inheriting the discriminants, or defining its own.
14229 -- type Ti is new Ti-1
14231 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
14233 -- subtype Ti is ...
14235 -- The subtype issue is avoided by the use of Original_Record_Component,
14236 -- and the fact that derived subtypes also derive the constraints.
14238 -- This chain leads back from
14240 -- Typ_For_Constraint
14242 -- Typ_For_Constraint has discriminants, and the value for each
14243 -- discriminant is given by its corresponding Elmt of Constraints.
14245 -- Discriminant is some discriminant in this hierarchy
14247 -- We need to return its value
14249 -- We do this by recursively searching each level, and looking for
14250 -- Discriminant. Once we get to the bottom, we start backing up
14251 -- returning the value for it which may in turn be a discriminant
14252 -- further up, so on the backup we continue the substitution.
14254 function Get_Discriminant_Value
14255 (Discriminant : Entity_Id;
14256 Typ_For_Constraint : Entity_Id;
14257 Constraint : Elist_Id) return Node_Id
14259 function Search_Derivation_Levels
14261 Discrim_Values : Elist_Id;
14262 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
14263 -- This is the routine that performs the recursive search of levels
14264 -- as described above.
14266 ------------------------------
14267 -- Search_Derivation_Levels --
14268 ------------------------------
14270 function Search_Derivation_Levels
14272 Discrim_Values : Elist_Id;
14273 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
14277 Result : Node_Or_Entity_Id;
14278 Result_Entity : Node_Id;
14281 -- If inappropriate type, return Error, this happens only in
14282 -- cascaded error situations, and we want to avoid a blow up.
14284 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
14288 -- Look deeper if possible. Use Stored_Constraints only for
14289 -- untagged types. For tagged types use the given constraint.
14290 -- This asymmetry needs explanation???
14292 if not Stored_Discrim_Values
14293 and then Present (Stored_Constraint (Ti))
14294 and then not Is_Tagged_Type (Ti)
14297 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
14300 Td : constant Entity_Id := Etype (Ti);
14304 Result := Discriminant;
14307 if Present (Stored_Constraint (Ti)) then
14309 Search_Derivation_Levels
14310 (Td, Stored_Constraint (Ti), True);
14313 Search_Derivation_Levels
14314 (Td, Discrim_Values, Stored_Discrim_Values);
14320 -- Extra underlying places to search, if not found above. For
14321 -- concurrent types, the relevant discriminant appears in the
14322 -- corresponding record. For a type derived from a private type
14323 -- without discriminant, the full view inherits the discriminants
14324 -- of the full view of the parent.
14326 if Result = Discriminant then
14327 if Is_Concurrent_Type (Ti)
14328 and then Present (Corresponding_Record_Type (Ti))
14331 Search_Derivation_Levels (
14332 Corresponding_Record_Type (Ti),
14334 Stored_Discrim_Values);
14336 elsif Is_Private_Type (Ti)
14337 and then not Has_Discriminants (Ti)
14338 and then Present (Full_View (Ti))
14339 and then Etype (Full_View (Ti)) /= Ti
14342 Search_Derivation_Levels (
14345 Stored_Discrim_Values);
14349 -- If Result is not a (reference to a) discriminant, return it,
14350 -- otherwise set Result_Entity to the discriminant.
14352 if Nkind (Result) = N_Defining_Identifier then
14353 pragma Assert (Result = Discriminant);
14354 Result_Entity := Result;
14357 if not Denotes_Discriminant (Result) then
14361 Result_Entity := Entity (Result);
14364 -- See if this level of derivation actually has discriminants
14365 -- because tagged derivations can add them, hence the lower
14366 -- levels need not have any.
14368 if not Has_Discriminants (Ti) then
14372 -- Scan Ti's discriminants for Result_Entity,
14373 -- and return its corresponding value, if any.
14375 Result_Entity := Original_Record_Component (Result_Entity);
14377 Assoc := First_Elmt (Discrim_Values);
14379 if Stored_Discrim_Values then
14380 Disc := First_Stored_Discriminant (Ti);
14382 Disc := First_Discriminant (Ti);
14385 while Present (Disc) loop
14386 pragma Assert (Present (Assoc));
14388 if Original_Record_Component (Disc) = Result_Entity then
14389 return Node (Assoc);
14394 if Stored_Discrim_Values then
14395 Next_Stored_Discriminant (Disc);
14397 Next_Discriminant (Disc);
14401 -- Could not find it
14404 end Search_Derivation_Levels;
14408 Result : Node_Or_Entity_Id;
14410 -- Start of processing for Get_Discriminant_Value
14413 -- ??? This routine is a gigantic mess and will be deleted. For the
14414 -- time being just test for the trivial case before calling recurse.
14416 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
14422 D := First_Discriminant (Typ_For_Constraint);
14423 E := First_Elmt (Constraint);
14424 while Present (D) loop
14425 if Chars (D) = Chars (Discriminant) then
14429 Next_Discriminant (D);
14435 Result := Search_Derivation_Levels
14436 (Typ_For_Constraint, Constraint, False);
14438 -- ??? hack to disappear when this routine is gone
14440 if Nkind (Result) = N_Defining_Identifier then
14446 D := First_Discriminant (Typ_For_Constraint);
14447 E := First_Elmt (Constraint);
14448 while Present (D) loop
14449 if Corresponding_Discriminant (D) = Discriminant then
14453 Next_Discriminant (D);
14459 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
14461 end Get_Discriminant_Value;
14463 --------------------------
14464 -- Has_Range_Constraint --
14465 --------------------------
14467 function Has_Range_Constraint (N : Node_Id) return Boolean is
14468 C : constant Node_Id := Constraint (N);
14471 if Nkind (C) = N_Range_Constraint then
14474 elsif Nkind (C) = N_Digits_Constraint then
14476 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
14478 Present (Range_Constraint (C));
14480 elsif Nkind (C) = N_Delta_Constraint then
14481 return Present (Range_Constraint (C));
14486 end Has_Range_Constraint;
14488 ------------------------
14489 -- Inherit_Components --
14490 ------------------------
14492 function Inherit_Components
14494 Parent_Base : Entity_Id;
14495 Derived_Base : Entity_Id;
14496 Is_Tagged : Boolean;
14497 Inherit_Discr : Boolean;
14498 Discs : Elist_Id) return Elist_Id
14500 Assoc_List : constant Elist_Id := New_Elmt_List;
14502 procedure Inherit_Component
14503 (Old_C : Entity_Id;
14504 Plain_Discrim : Boolean := False;
14505 Stored_Discrim : Boolean := False);
14506 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
14507 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
14508 -- True, Old_C is a stored discriminant. If they are both false then
14509 -- Old_C is a regular component.
14511 -----------------------
14512 -- Inherit_Component --
14513 -----------------------
14515 procedure Inherit_Component
14516 (Old_C : Entity_Id;
14517 Plain_Discrim : Boolean := False;
14518 Stored_Discrim : Boolean := False)
14520 New_C : constant Entity_Id := New_Copy (Old_C);
14522 Discrim : Entity_Id;
14523 Corr_Discrim : Entity_Id;
14526 pragma Assert (not Is_Tagged or else not Stored_Discrim);
14528 Set_Parent (New_C, Parent (Old_C));
14530 -- Regular discriminants and components must be inserted in the scope
14531 -- of the Derived_Base. Do it here.
14533 if not Stored_Discrim then
14534 Enter_Name (New_C);
14537 -- For tagged types the Original_Record_Component must point to
14538 -- whatever this field was pointing to in the parent type. This has
14539 -- already been achieved by the call to New_Copy above.
14541 if not Is_Tagged then
14542 Set_Original_Record_Component (New_C, New_C);
14545 -- If we have inherited a component then see if its Etype contains
14546 -- references to Parent_Base discriminants. In this case, replace
14547 -- these references with the constraints given in Discs. We do not
14548 -- do this for the partial view of private types because this is
14549 -- not needed (only the components of the full view will be used
14550 -- for code generation) and cause problem. We also avoid this
14551 -- transformation in some error situations.
14553 if Ekind (New_C) = E_Component then
14554 if (Is_Private_Type (Derived_Base)
14555 and then not Is_Generic_Type (Derived_Base))
14556 or else (Is_Empty_Elmt_List (Discs)
14557 and then not Expander_Active)
14559 Set_Etype (New_C, Etype (Old_C));
14562 -- The current component introduces a circularity of the
14565 -- limited with Pack_2;
14566 -- package Pack_1 is
14567 -- type T_1 is tagged record
14568 -- Comp : access Pack_2.T_2;
14574 -- package Pack_2 is
14575 -- type T_2 is new Pack_1.T_1 with ...;
14580 Constrain_Component_Type
14581 (Old_C, Derived_Base, N, Parent_Base, Discs));
14585 -- In derived tagged types it is illegal to reference a non
14586 -- discriminant component in the parent type. To catch this, mark
14587 -- these components with an Ekind of E_Void. This will be reset in
14588 -- Record_Type_Definition after processing the record extension of
14589 -- the derived type.
14591 -- If the declaration is a private extension, there is no further
14592 -- record extension to process, and the components retain their
14593 -- current kind, because they are visible at this point.
14595 if Is_Tagged and then Ekind (New_C) = E_Component
14596 and then Nkind (N) /= N_Private_Extension_Declaration
14598 Set_Ekind (New_C, E_Void);
14601 if Plain_Discrim then
14602 Set_Corresponding_Discriminant (New_C, Old_C);
14603 Build_Discriminal (New_C);
14605 -- If we are explicitly inheriting a stored discriminant it will be
14606 -- completely hidden.
14608 elsif Stored_Discrim then
14609 Set_Corresponding_Discriminant (New_C, Empty);
14610 Set_Discriminal (New_C, Empty);
14611 Set_Is_Completely_Hidden (New_C);
14613 -- Set the Original_Record_Component of each discriminant in the
14614 -- derived base to point to the corresponding stored that we just
14617 Discrim := First_Discriminant (Derived_Base);
14618 while Present (Discrim) loop
14619 Corr_Discrim := Corresponding_Discriminant (Discrim);
14621 -- Corr_Discrim could be missing in an error situation
14623 if Present (Corr_Discrim)
14624 and then Original_Record_Component (Corr_Discrim) = Old_C
14626 Set_Original_Record_Component (Discrim, New_C);
14629 Next_Discriminant (Discrim);
14632 Append_Entity (New_C, Derived_Base);
14635 if not Is_Tagged then
14636 Append_Elmt (Old_C, Assoc_List);
14637 Append_Elmt (New_C, Assoc_List);
14639 end Inherit_Component;
14641 -- Variables local to Inherit_Component
14643 Loc : constant Source_Ptr := Sloc (N);
14645 Parent_Discrim : Entity_Id;
14646 Stored_Discrim : Entity_Id;
14648 Component : Entity_Id;
14650 -- Start of processing for Inherit_Components
14653 if not Is_Tagged then
14654 Append_Elmt (Parent_Base, Assoc_List);
14655 Append_Elmt (Derived_Base, Assoc_List);
14658 -- Inherit parent discriminants if needed
14660 if Inherit_Discr then
14661 Parent_Discrim := First_Discriminant (Parent_Base);
14662 while Present (Parent_Discrim) loop
14663 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
14664 Next_Discriminant (Parent_Discrim);
14668 -- Create explicit stored discrims for untagged types when necessary
14670 if not Has_Unknown_Discriminants (Derived_Base)
14671 and then Has_Discriminants (Parent_Base)
14672 and then not Is_Tagged
14675 or else First_Discriminant (Parent_Base) /=
14676 First_Stored_Discriminant (Parent_Base))
14678 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
14679 while Present (Stored_Discrim) loop
14680 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
14681 Next_Stored_Discriminant (Stored_Discrim);
14685 -- See if we can apply the second transformation for derived types, as
14686 -- explained in point 6. in the comments above Build_Derived_Record_Type
14687 -- This is achieved by appending Derived_Base discriminants into Discs,
14688 -- which has the side effect of returning a non empty Discs list to the
14689 -- caller of Inherit_Components, which is what we want. This must be
14690 -- done for private derived types if there are explicit stored
14691 -- discriminants, to ensure that we can retrieve the values of the
14692 -- constraints provided in the ancestors.
14695 and then Is_Empty_Elmt_List (Discs)
14696 and then Present (First_Discriminant (Derived_Base))
14698 (not Is_Private_Type (Derived_Base)
14699 or else Is_Completely_Hidden
14700 (First_Stored_Discriminant (Derived_Base))
14701 or else Is_Generic_Type (Derived_Base))
14703 D := First_Discriminant (Derived_Base);
14704 while Present (D) loop
14705 Append_Elmt (New_Reference_To (D, Loc), Discs);
14706 Next_Discriminant (D);
14710 -- Finally, inherit non-discriminant components unless they are not
14711 -- visible because defined or inherited from the full view of the
14712 -- parent. Don't inherit the _parent field of the parent type.
14714 Component := First_Entity (Parent_Base);
14715 while Present (Component) loop
14717 -- Ada 2005 (AI-251): Do not inherit components associated with
14718 -- secondary tags of the parent.
14720 if Ekind (Component) = E_Component
14721 and then Present (Related_Type (Component))
14725 elsif Ekind (Component) /= E_Component
14726 or else Chars (Component) = Name_uParent
14730 -- If the derived type is within the parent type's declarative
14731 -- region, then the components can still be inherited even though
14732 -- they aren't visible at this point. This can occur for cases
14733 -- such as within public child units where the components must
14734 -- become visible upon entering the child unit's private part.
14736 elsif not Is_Visible_Component (Component)
14737 and then not In_Open_Scopes (Scope (Parent_Base))
14741 elsif Ekind (Derived_Base) = E_Private_Type
14742 or else Ekind (Derived_Base) = E_Limited_Private_Type
14747 Inherit_Component (Component);
14750 Next_Entity (Component);
14753 -- For tagged derived types, inherited discriminants cannot be used in
14754 -- component declarations of the record extension part. To achieve this
14755 -- we mark the inherited discriminants as not visible.
14757 if Is_Tagged and then Inherit_Discr then
14758 D := First_Discriminant (Derived_Base);
14759 while Present (D) loop
14760 Set_Is_Immediately_Visible (D, False);
14761 Next_Discriminant (D);
14766 end Inherit_Components;
14768 -----------------------
14769 -- Is_Null_Extension --
14770 -----------------------
14772 function Is_Null_Extension (T : Entity_Id) return Boolean is
14773 Type_Decl : constant Node_Id := Parent (Base_Type (T));
14774 Comp_List : Node_Id;
14778 if Nkind (Type_Decl) /= N_Full_Type_Declaration
14779 or else not Is_Tagged_Type (T)
14780 or else Nkind (Type_Definition (Type_Decl)) /=
14781 N_Derived_Type_Definition
14782 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
14788 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
14790 if Present (Discriminant_Specifications (Type_Decl)) then
14793 elsif Present (Comp_List)
14794 and then Is_Non_Empty_List (Component_Items (Comp_List))
14796 Comp := First (Component_Items (Comp_List));
14798 -- Only user-defined components are relevant. The component list
14799 -- may also contain a parent component and internal components
14800 -- corresponding to secondary tags, but these do not determine
14801 -- whether this is a null extension.
14803 while Present (Comp) loop
14804 if Comes_From_Source (Comp) then
14815 end Is_Null_Extension;
14817 --------------------
14818 -- Is_Progenitor --
14819 --------------------
14821 function Is_Progenitor
14822 (Iface : Entity_Id;
14823 Typ : Entity_Id) return Boolean
14826 return Implements_Interface (Typ, Iface,
14827 Exclude_Parents => True);
14830 ------------------------------
14831 -- Is_Valid_Constraint_Kind --
14832 ------------------------------
14834 function Is_Valid_Constraint_Kind
14835 (T_Kind : Type_Kind;
14836 Constraint_Kind : Node_Kind) return Boolean
14840 when Enumeration_Kind |
14842 return Constraint_Kind = N_Range_Constraint;
14844 when Decimal_Fixed_Point_Kind =>
14845 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
14846 N_Range_Constraint);
14848 when Ordinary_Fixed_Point_Kind =>
14849 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
14850 N_Range_Constraint);
14853 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
14854 N_Range_Constraint);
14861 E_Incomplete_Type |
14864 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
14867 return True; -- Error will be detected later
14869 end Is_Valid_Constraint_Kind;
14871 --------------------------
14872 -- Is_Visible_Component --
14873 --------------------------
14875 function Is_Visible_Component (C : Entity_Id) return Boolean is
14876 Original_Comp : Entity_Id := Empty;
14877 Original_Scope : Entity_Id;
14878 Type_Scope : Entity_Id;
14880 function Is_Local_Type (Typ : Entity_Id) return Boolean;
14881 -- Check whether parent type of inherited component is declared locally,
14882 -- possibly within a nested package or instance. The current scope is
14883 -- the derived record itself.
14885 -------------------
14886 -- Is_Local_Type --
14887 -------------------
14889 function Is_Local_Type (Typ : Entity_Id) return Boolean is
14893 Scop := Scope (Typ);
14894 while Present (Scop)
14895 and then Scop /= Standard_Standard
14897 if Scop = Scope (Current_Scope) then
14901 Scop := Scope (Scop);
14907 -- Start of processing for Is_Visible_Component
14910 if Ekind (C) = E_Component
14911 or else Ekind (C) = E_Discriminant
14913 Original_Comp := Original_Record_Component (C);
14916 if No (Original_Comp) then
14918 -- Premature usage, or previous error
14923 Original_Scope := Scope (Original_Comp);
14924 Type_Scope := Scope (Base_Type (Scope (C)));
14927 -- This test only concerns tagged types
14929 if not Is_Tagged_Type (Original_Scope) then
14932 -- If it is _Parent or _Tag, there is no visibility issue
14934 elsif not Comes_From_Source (Original_Comp) then
14937 -- If we are in the body of an instantiation, the component is visible
14938 -- even when the parent type (possibly defined in an enclosing unit or
14939 -- in a parent unit) might not.
14941 elsif In_Instance_Body then
14944 -- Discriminants are always visible
14946 elsif Ekind (Original_Comp) = E_Discriminant
14947 and then not Has_Unknown_Discriminants (Original_Scope)
14951 -- If the component has been declared in an ancestor which is currently
14952 -- a private type, then it is not visible. The same applies if the
14953 -- component's containing type is not in an open scope and the original
14954 -- component's enclosing type is a visible full view of a private type
14955 -- (which can occur in cases where an attempt is being made to reference
14956 -- a component in a sibling package that is inherited from a visible
14957 -- component of a type in an ancestor package; the component in the
14958 -- sibling package should not be visible even though the component it
14959 -- inherited from is visible). This does not apply however in the case
14960 -- where the scope of the type is a private child unit, or when the
14961 -- parent comes from a local package in which the ancestor is currently
14962 -- visible. The latter suppression of visibility is needed for cases
14963 -- that are tested in B730006.
14965 elsif Is_Private_Type (Original_Scope)
14967 (not Is_Private_Descendant (Type_Scope)
14968 and then not In_Open_Scopes (Type_Scope)
14969 and then Has_Private_Declaration (Original_Scope))
14971 -- If the type derives from an entity in a formal package, there
14972 -- are no additional visible components.
14974 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
14975 N_Formal_Package_Declaration
14979 -- if we are not in the private part of the current package, there
14980 -- are no additional visible components.
14982 elsif Ekind (Scope (Current_Scope)) = E_Package
14983 and then not In_Private_Part (Scope (Current_Scope))
14988 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
14989 and then In_Open_Scopes (Scope (Original_Scope))
14990 and then Is_Local_Type (Type_Scope);
14993 -- There is another weird way in which a component may be invisible
14994 -- when the private and the full view are not derived from the same
14995 -- ancestor. Here is an example :
14997 -- type A1 is tagged record F1 : integer; end record;
14998 -- type A2 is new A1 with record F2 : integer; end record;
14999 -- type T is new A1 with private;
15001 -- type T is new A2 with null record;
15003 -- In this case, the full view of T inherits F1 and F2 but the private
15004 -- view inherits only F1
15008 Ancestor : Entity_Id := Scope (C);
15012 if Ancestor = Original_Scope then
15014 elsif Ancestor = Etype (Ancestor) then
15018 Ancestor := Etype (Ancestor);
15022 end Is_Visible_Component;
15024 --------------------------
15025 -- Make_Class_Wide_Type --
15026 --------------------------
15028 procedure Make_Class_Wide_Type (T : Entity_Id) is
15029 CW_Type : Entity_Id;
15031 Next_E : Entity_Id;
15034 -- The class wide type can have been defined by the partial view, in
15035 -- which case everything is already done.
15037 if Present (Class_Wide_Type (T)) then
15042 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
15044 -- Inherit root type characteristics
15046 CW_Name := Chars (CW_Type);
15047 Next_E := Next_Entity (CW_Type);
15048 Copy_Node (T, CW_Type);
15049 Set_Comes_From_Source (CW_Type, False);
15050 Set_Chars (CW_Type, CW_Name);
15051 Set_Parent (CW_Type, Parent (T));
15052 Set_Next_Entity (CW_Type, Next_E);
15054 -- Ensure we have a new freeze node for the class-wide type. The partial
15055 -- view may have freeze action of its own, requiring a proper freeze
15056 -- node, and the same freeze node cannot be shared between the two
15059 Set_Has_Delayed_Freeze (CW_Type);
15060 Set_Freeze_Node (CW_Type, Empty);
15062 -- Customize the class-wide type: It has no prim. op., it cannot be
15063 -- abstract and its Etype points back to the specific root type.
15065 Set_Ekind (CW_Type, E_Class_Wide_Type);
15066 Set_Is_Tagged_Type (CW_Type, True);
15067 Set_Primitive_Operations (CW_Type, New_Elmt_List);
15068 Set_Is_Abstract_Type (CW_Type, False);
15069 Set_Is_Constrained (CW_Type, False);
15070 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
15072 if Ekind (T) = E_Class_Wide_Subtype then
15073 Set_Etype (CW_Type, Etype (Base_Type (T)));
15075 Set_Etype (CW_Type, T);
15078 -- If this is the class_wide type of a constrained subtype, it does
15079 -- not have discriminants.
15081 Set_Has_Discriminants (CW_Type,
15082 Has_Discriminants (T) and then not Is_Constrained (T));
15084 Set_Has_Unknown_Discriminants (CW_Type, True);
15085 Set_Class_Wide_Type (T, CW_Type);
15086 Set_Equivalent_Type (CW_Type, Empty);
15088 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
15090 Set_Class_Wide_Type (CW_Type, CW_Type);
15091 end Make_Class_Wide_Type;
15097 procedure Make_Index
15099 Related_Nod : Node_Id;
15100 Related_Id : Entity_Id := Empty;
15101 Suffix_Index : Nat := 1)
15105 Def_Id : Entity_Id := Empty;
15106 Found : Boolean := False;
15109 -- For a discrete range used in a constrained array definition and
15110 -- defined by a range, an implicit conversion to the predefined type
15111 -- INTEGER is assumed if each bound is either a numeric literal, a named
15112 -- number, or an attribute, and the type of both bounds (prior to the
15113 -- implicit conversion) is the type universal_integer. Otherwise, both
15114 -- bounds must be of the same discrete type, other than universal
15115 -- integer; this type must be determinable independently of the
15116 -- context, but using the fact that the type must be discrete and that
15117 -- both bounds must have the same type.
15119 -- Character literals also have a universal type in the absence of
15120 -- of additional context, and are resolved to Standard_Character.
15122 if Nkind (I) = N_Range then
15124 -- The index is given by a range constraint. The bounds are known
15125 -- to be of a consistent type.
15127 if not Is_Overloaded (I) then
15130 -- For universal bounds, choose the specific predefined type
15132 if T = Universal_Integer then
15133 T := Standard_Integer;
15135 elsif T = Any_Character then
15136 Ambiguous_Character (Low_Bound (I));
15138 T := Standard_Character;
15141 -- The node may be overloaded because some user-defined operators
15142 -- are available, but if a universal interpretation exists it is
15143 -- also the selected one.
15145 elsif Universal_Interpretation (I) = Universal_Integer then
15146 T := Standard_Integer;
15152 Ind : Interp_Index;
15156 Get_First_Interp (I, Ind, It);
15157 while Present (It.Typ) loop
15158 if Is_Discrete_Type (It.Typ) then
15161 and then not Covers (It.Typ, T)
15162 and then not Covers (T, It.Typ)
15164 Error_Msg_N ("ambiguous bounds in discrete range", I);
15172 Get_Next_Interp (Ind, It);
15175 if T = Any_Type then
15176 Error_Msg_N ("discrete type required for range", I);
15177 Set_Etype (I, Any_Type);
15180 elsif T = Universal_Integer then
15181 T := Standard_Integer;
15186 if not Is_Discrete_Type (T) then
15187 Error_Msg_N ("discrete type required for range", I);
15188 Set_Etype (I, Any_Type);
15192 if Nkind (Low_Bound (I)) = N_Attribute_Reference
15193 and then Attribute_Name (Low_Bound (I)) = Name_First
15194 and then Is_Entity_Name (Prefix (Low_Bound (I)))
15195 and then Is_Type (Entity (Prefix (Low_Bound (I))))
15196 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (I))))
15198 -- The type of the index will be the type of the prefix, as long
15199 -- as the upper bound is 'Last of the same type.
15201 Def_Id := Entity (Prefix (Low_Bound (I)));
15203 if Nkind (High_Bound (I)) /= N_Attribute_Reference
15204 or else Attribute_Name (High_Bound (I)) /= Name_Last
15205 or else not Is_Entity_Name (Prefix (High_Bound (I)))
15206 or else Entity (Prefix (High_Bound (I))) /= Def_Id
15213 Process_Range_Expr_In_Decl (R, T);
15215 elsif Nkind (I) = N_Subtype_Indication then
15217 -- The index is given by a subtype with a range constraint
15219 T := Base_Type (Entity (Subtype_Mark (I)));
15221 if not Is_Discrete_Type (T) then
15222 Error_Msg_N ("discrete type required for range", I);
15223 Set_Etype (I, Any_Type);
15227 R := Range_Expression (Constraint (I));
15230 Process_Range_Expr_In_Decl (R, Entity (Subtype_Mark (I)));
15232 elsif Nkind (I) = N_Attribute_Reference then
15234 -- The parser guarantees that the attribute is a RANGE attribute
15236 -- If the node denotes the range of a type mark, that is also the
15237 -- resulting type, and we do no need to create an Itype for it.
15239 if Is_Entity_Name (Prefix (I))
15240 and then Comes_From_Source (I)
15241 and then Is_Type (Entity (Prefix (I)))
15242 and then Is_Discrete_Type (Entity (Prefix (I)))
15244 Def_Id := Entity (Prefix (I));
15247 Analyze_And_Resolve (I);
15251 -- If none of the above, must be a subtype. We convert this to a
15252 -- range attribute reference because in the case of declared first
15253 -- named subtypes, the types in the range reference can be different
15254 -- from the type of the entity. A range attribute normalizes the
15255 -- reference and obtains the correct types for the bounds.
15257 -- This transformation is in the nature of an expansion, is only
15258 -- done if expansion is active. In particular, it is not done on
15259 -- formal generic types, because we need to retain the name of the
15260 -- original index for instantiation purposes.
15263 if not Is_Entity_Name (I) or else not Is_Type (Entity (I)) then
15264 Error_Msg_N ("invalid subtype mark in discrete range ", I);
15265 Set_Etype (I, Any_Integer);
15269 -- The type mark may be that of an incomplete type. It is only
15270 -- now that we can get the full view, previous analysis does
15271 -- not look specifically for a type mark.
15273 Set_Entity (I, Get_Full_View (Entity (I)));
15274 Set_Etype (I, Entity (I));
15275 Def_Id := Entity (I);
15277 if not Is_Discrete_Type (Def_Id) then
15278 Error_Msg_N ("discrete type required for index", I);
15279 Set_Etype (I, Any_Type);
15284 if Expander_Active then
15286 Make_Attribute_Reference (Sloc (I),
15287 Attribute_Name => Name_Range,
15288 Prefix => Relocate_Node (I)));
15290 -- The original was a subtype mark that does not freeze. This
15291 -- means that the rewritten version must not freeze either.
15293 Set_Must_Not_Freeze (I);
15294 Set_Must_Not_Freeze (Prefix (I));
15296 -- Is order critical??? if so, document why, if not
15297 -- use Analyze_And_Resolve
15299 Analyze_And_Resolve (I);
15303 -- If expander is inactive, type is legal, nothing else to construct
15310 if not Is_Discrete_Type (T) then
15311 Error_Msg_N ("discrete type required for range", I);
15312 Set_Etype (I, Any_Type);
15315 elsif T = Any_Type then
15316 Set_Etype (I, Any_Type);
15320 -- We will now create the appropriate Itype to describe the range, but
15321 -- first a check. If we originally had a subtype, then we just label
15322 -- the range with this subtype. Not only is there no need to construct
15323 -- a new subtype, but it is wrong to do so for two reasons:
15325 -- 1. A legality concern, if we have a subtype, it must not freeze,
15326 -- and the Itype would cause freezing incorrectly
15328 -- 2. An efficiency concern, if we created an Itype, it would not be
15329 -- recognized as the same type for the purposes of eliminating
15330 -- checks in some circumstances.
15332 -- We signal this case by setting the subtype entity in Def_Id
15334 if No (Def_Id) then
15336 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
15337 Set_Etype (Def_Id, Base_Type (T));
15339 if Is_Signed_Integer_Type (T) then
15340 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
15342 elsif Is_Modular_Integer_Type (T) then
15343 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
15346 Set_Ekind (Def_Id, E_Enumeration_Subtype);
15347 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
15348 Set_First_Literal (Def_Id, First_Literal (T));
15351 Set_Size_Info (Def_Id, (T));
15352 Set_RM_Size (Def_Id, RM_Size (T));
15353 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
15355 Set_Scalar_Range (Def_Id, R);
15356 Conditional_Delay (Def_Id, T);
15358 -- In the subtype indication case, if the immediate parent of the
15359 -- new subtype is non-static, then the subtype we create is non-
15360 -- static, even if its bounds are static.
15362 if Nkind (I) = N_Subtype_Indication
15363 and then not Is_Static_Subtype (Entity (Subtype_Mark (I)))
15365 Set_Is_Non_Static_Subtype (Def_Id);
15369 -- Final step is to label the index with this constructed type
15371 Set_Etype (I, Def_Id);
15374 ------------------------------
15375 -- Modular_Type_Declaration --
15376 ------------------------------
15378 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
15379 Mod_Expr : constant Node_Id := Expression (Def);
15382 procedure Set_Modular_Size (Bits : Int);
15383 -- Sets RM_Size to Bits, and Esize to normal word size above this
15385 ----------------------
15386 -- Set_Modular_Size --
15387 ----------------------
15389 procedure Set_Modular_Size (Bits : Int) is
15391 Set_RM_Size (T, UI_From_Int (Bits));
15396 elsif Bits <= 16 then
15397 Init_Esize (T, 16);
15399 elsif Bits <= 32 then
15400 Init_Esize (T, 32);
15403 Init_Esize (T, System_Max_Binary_Modulus_Power);
15406 if not Non_Binary_Modulus (T)
15407 and then Esize (T) = RM_Size (T)
15409 Set_Is_Known_Valid (T);
15411 end Set_Modular_Size;
15413 -- Start of processing for Modular_Type_Declaration
15416 Analyze_And_Resolve (Mod_Expr, Any_Integer);
15418 Set_Ekind (T, E_Modular_Integer_Type);
15419 Init_Alignment (T);
15420 Set_Is_Constrained (T);
15422 if not Is_OK_Static_Expression (Mod_Expr) then
15423 Flag_Non_Static_Expr
15424 ("non-static expression used for modular type bound!", Mod_Expr);
15425 M_Val := 2 ** System_Max_Binary_Modulus_Power;
15427 M_Val := Expr_Value (Mod_Expr);
15431 Error_Msg_N ("modulus value must be positive", Mod_Expr);
15432 M_Val := 2 ** System_Max_Binary_Modulus_Power;
15435 Set_Modulus (T, M_Val);
15437 -- Create bounds for the modular type based on the modulus given in
15438 -- the type declaration and then analyze and resolve those bounds.
15440 Set_Scalar_Range (T,
15441 Make_Range (Sloc (Mod_Expr),
15443 Make_Integer_Literal (Sloc (Mod_Expr), 0),
15445 Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
15447 -- Properly analyze the literals for the range. We do this manually
15448 -- because we can't go calling Resolve, since we are resolving these
15449 -- bounds with the type, and this type is certainly not complete yet!
15451 Set_Etype (Low_Bound (Scalar_Range (T)), T);
15452 Set_Etype (High_Bound (Scalar_Range (T)), T);
15453 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
15454 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
15456 -- Loop through powers of two to find number of bits required
15458 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
15462 if M_Val = 2 ** Bits then
15463 Set_Modular_Size (Bits);
15468 elsif M_Val < 2 ** Bits then
15469 Set_Non_Binary_Modulus (T);
15471 if Bits > System_Max_Nonbinary_Modulus_Power then
15472 Error_Msg_Uint_1 :=
15473 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
15475 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
15476 Set_Modular_Size (System_Max_Binary_Modulus_Power);
15480 -- In the non-binary case, set size as per RM 13.3(55)
15482 Set_Modular_Size (Bits);
15489 -- If we fall through, then the size exceed System.Max_Binary_Modulus
15490 -- so we just signal an error and set the maximum size.
15492 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
15493 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
15495 Set_Modular_Size (System_Max_Binary_Modulus_Power);
15496 Init_Alignment (T);
15498 end Modular_Type_Declaration;
15500 --------------------------
15501 -- New_Concatenation_Op --
15502 --------------------------
15504 procedure New_Concatenation_Op (Typ : Entity_Id) is
15505 Loc : constant Source_Ptr := Sloc (Typ);
15508 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
15509 -- Create abbreviated declaration for the formal of a predefined
15510 -- Operator 'Op' of type 'Typ'
15512 --------------------
15513 -- Make_Op_Formal --
15514 --------------------
15516 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
15517 Formal : Entity_Id;
15519 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
15520 Set_Etype (Formal, Typ);
15521 Set_Mechanism (Formal, Default_Mechanism);
15523 end Make_Op_Formal;
15525 -- Start of processing for New_Concatenation_Op
15528 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
15530 Set_Ekind (Op, E_Operator);
15531 Set_Scope (Op, Current_Scope);
15532 Set_Etype (Op, Typ);
15533 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
15534 Set_Is_Immediately_Visible (Op);
15535 Set_Is_Intrinsic_Subprogram (Op);
15536 Set_Has_Completion (Op);
15537 Append_Entity (Op, Current_Scope);
15539 Set_Name_Entity_Id (Name_Op_Concat, Op);
15541 Append_Entity (Make_Op_Formal (Typ, Op), Op);
15542 Append_Entity (Make_Op_Formal (Typ, Op), Op);
15543 end New_Concatenation_Op;
15545 -------------------------
15546 -- OK_For_Limited_Init --
15547 -------------------------
15549 -- ???Check all calls of this, and compare the conditions under which it's
15552 function OK_For_Limited_Init
15554 Exp : Node_Id) return Boolean
15557 return Is_CPP_Constructor_Call (Exp)
15558 or else (Ada_Version >= Ada_05
15559 and then not Debug_Flag_Dot_L
15560 and then OK_For_Limited_Init_In_05 (Typ, Exp));
15561 end OK_For_Limited_Init;
15563 -------------------------------
15564 -- OK_For_Limited_Init_In_05 --
15565 -------------------------------
15567 function OK_For_Limited_Init_In_05
15569 Exp : Node_Id) return Boolean
15572 -- An object of a limited interface type can be initialized with any
15573 -- expression of a nonlimited descendant type.
15575 if Is_Class_Wide_Type (Typ)
15576 and then Is_Limited_Interface (Typ)
15577 and then not Is_Limited_Type (Etype (Exp))
15582 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
15583 -- case of limited aggregates (including extension aggregates), and
15584 -- function calls. The function call may have been give in prefixed
15585 -- notation, in which case the original node is an indexed component.
15587 case Nkind (Original_Node (Exp)) is
15588 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
15591 when N_Qualified_Expression =>
15593 OK_For_Limited_Init_In_05
15594 (Typ, Expression (Original_Node (Exp)));
15596 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
15597 -- with a function call, the expander has rewritten the call into an
15598 -- N_Type_Conversion node to force displacement of the pointer to
15599 -- reference the component containing the secondary dispatch table.
15600 -- Otherwise a type conversion is not a legal context.
15601 -- A return statement for a build-in-place function returning a
15602 -- synchronized type also introduces an unchecked conversion.
15604 when N_Type_Conversion | N_Unchecked_Type_Conversion =>
15605 return not Comes_From_Source (Exp)
15607 OK_For_Limited_Init_In_05
15608 (Typ, Expression (Original_Node (Exp)));
15610 when N_Indexed_Component | N_Selected_Component =>
15611 return Nkind (Exp) = N_Function_Call;
15613 -- A use of 'Input is a function call, hence allowed. Normally the
15614 -- attribute will be changed to a call, but the attribute by itself
15615 -- can occur with -gnatc.
15617 when N_Attribute_Reference =>
15618 return Attribute_Name (Original_Node (Exp)) = Name_Input;
15623 end OK_For_Limited_Init_In_05;
15625 -------------------------------------------
15626 -- Ordinary_Fixed_Point_Type_Declaration --
15627 -------------------------------------------
15629 procedure Ordinary_Fixed_Point_Type_Declaration
15633 Loc : constant Source_Ptr := Sloc (Def);
15634 Delta_Expr : constant Node_Id := Delta_Expression (Def);
15635 RRS : constant Node_Id := Real_Range_Specification (Def);
15636 Implicit_Base : Entity_Id;
15643 Check_Restriction (No_Fixed_Point, Def);
15645 -- Create implicit base type
15648 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
15649 Set_Etype (Implicit_Base, Implicit_Base);
15651 -- Analyze and process delta expression
15653 Analyze_And_Resolve (Delta_Expr, Any_Real);
15655 Check_Delta_Expression (Delta_Expr);
15656 Delta_Val := Expr_Value_R (Delta_Expr);
15658 Set_Delta_Value (Implicit_Base, Delta_Val);
15660 -- Compute default small from given delta, which is the largest power
15661 -- of two that does not exceed the given delta value.
15671 if Delta_Val < Ureal_1 then
15672 while Delta_Val < Tmp loop
15673 Tmp := Tmp / Ureal_2;
15674 Scale := Scale + 1;
15679 Tmp := Tmp * Ureal_2;
15680 exit when Tmp > Delta_Val;
15681 Scale := Scale - 1;
15685 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
15688 Set_Small_Value (Implicit_Base, Small_Val);
15690 -- If no range was given, set a dummy range
15692 if RRS <= Empty_Or_Error then
15693 Low_Val := -Small_Val;
15694 High_Val := Small_Val;
15696 -- Otherwise analyze and process given range
15700 Low : constant Node_Id := Low_Bound (RRS);
15701 High : constant Node_Id := High_Bound (RRS);
15704 Analyze_And_Resolve (Low, Any_Real);
15705 Analyze_And_Resolve (High, Any_Real);
15706 Check_Real_Bound (Low);
15707 Check_Real_Bound (High);
15709 -- Obtain and set the range
15711 Low_Val := Expr_Value_R (Low);
15712 High_Val := Expr_Value_R (High);
15714 if Low_Val > High_Val then
15715 Error_Msg_NE ("?fixed point type& has null range", Def, T);
15720 -- The range for both the implicit base and the declared first subtype
15721 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
15722 -- set a temporary range in place. Note that the bounds of the base
15723 -- type will be widened to be symmetrical and to fill the available
15724 -- bits when the type is frozen.
15726 -- We could do this with all discrete types, and probably should, but
15727 -- we absolutely have to do it for fixed-point, since the end-points
15728 -- of the range and the size are determined by the small value, which
15729 -- could be reset before the freeze point.
15731 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
15732 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
15734 -- Complete definition of first subtype
15736 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
15737 Set_Etype (T, Implicit_Base);
15738 Init_Size_Align (T);
15739 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
15740 Set_Small_Value (T, Small_Val);
15741 Set_Delta_Value (T, Delta_Val);
15742 Set_Is_Constrained (T);
15744 end Ordinary_Fixed_Point_Type_Declaration;
15746 ----------------------------------------
15747 -- Prepare_Private_Subtype_Completion --
15748 ----------------------------------------
15750 procedure Prepare_Private_Subtype_Completion
15752 Related_Nod : Node_Id)
15754 Id_B : constant Entity_Id := Base_Type (Id);
15755 Full_B : constant Entity_Id := Full_View (Id_B);
15759 if Present (Full_B) then
15761 -- The Base_Type is already completed, we can complete the subtype
15762 -- now. We have to create a new entity with the same name, Thus we
15763 -- can't use Create_Itype.
15765 -- This is messy, should be fixed ???
15767 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
15768 Set_Is_Itype (Full);
15769 Set_Associated_Node_For_Itype (Full, Related_Nod);
15770 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
15773 -- The parent subtype may be private, but the base might not, in some
15774 -- nested instances. In that case, the subtype does not need to be
15775 -- exchanged. It would still be nice to make private subtypes and their
15776 -- bases consistent at all times ???
15778 if Is_Private_Type (Id_B) then
15779 Append_Elmt (Id, Private_Dependents (Id_B));
15782 end Prepare_Private_Subtype_Completion;
15784 ---------------------------
15785 -- Process_Discriminants --
15786 ---------------------------
15788 procedure Process_Discriminants
15790 Prev : Entity_Id := Empty)
15792 Elist : constant Elist_Id := New_Elmt_List;
15795 Discr_Number : Uint;
15796 Discr_Type : Entity_Id;
15797 Default_Present : Boolean := False;
15798 Default_Not_Present : Boolean := False;
15801 -- A composite type other than an array type can have discriminants.
15802 -- On entry, the current scope is the composite type.
15804 -- The discriminants are initially entered into the scope of the type
15805 -- via Enter_Name with the default Ekind of E_Void to prevent premature
15806 -- use, as explained at the end of this procedure.
15808 Discr := First (Discriminant_Specifications (N));
15809 while Present (Discr) loop
15810 Enter_Name (Defining_Identifier (Discr));
15812 -- For navigation purposes we add a reference to the discriminant
15813 -- in the entity for the type. If the current declaration is a
15814 -- completion, place references on the partial view. Otherwise the
15815 -- type is the current scope.
15817 if Present (Prev) then
15819 -- The references go on the partial view, if present. If the
15820 -- partial view has discriminants, the references have been
15821 -- generated already.
15823 if not Has_Discriminants (Prev) then
15824 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
15828 (Current_Scope, Defining_Identifier (Discr), 'd');
15831 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
15832 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
15834 -- Ada 2005 (AI-254)
15836 if Present (Access_To_Subprogram_Definition
15837 (Discriminant_Type (Discr)))
15838 and then Protected_Present (Access_To_Subprogram_Definition
15839 (Discriminant_Type (Discr)))
15842 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
15846 Find_Type (Discriminant_Type (Discr));
15847 Discr_Type := Etype (Discriminant_Type (Discr));
15849 if Error_Posted (Discriminant_Type (Discr)) then
15850 Discr_Type := Any_Type;
15854 if Is_Access_Type (Discr_Type) then
15856 -- Ada 2005 (AI-230): Access discriminant allowed in non-limited
15859 if Ada_Version < Ada_05 then
15860 Check_Access_Discriminant_Requires_Limited
15861 (Discr, Discriminant_Type (Discr));
15864 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
15866 ("(Ada 83) access discriminant not allowed", Discr);
15869 elsif not Is_Discrete_Type (Discr_Type) then
15870 Error_Msg_N ("discriminants must have a discrete or access type",
15871 Discriminant_Type (Discr));
15874 Set_Etype (Defining_Identifier (Discr), Discr_Type);
15876 -- If a discriminant specification includes the assignment compound
15877 -- delimiter followed by an expression, the expression is the default
15878 -- expression of the discriminant; the default expression must be of
15879 -- the type of the discriminant. (RM 3.7.1) Since this expression is
15880 -- a default expression, we do the special preanalysis, since this
15881 -- expression does not freeze (see "Handling of Default and Per-
15882 -- Object Expressions" in spec of package Sem).
15884 if Present (Expression (Discr)) then
15885 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
15887 if Nkind (N) = N_Formal_Type_Declaration then
15889 ("discriminant defaults not allowed for formal type",
15890 Expression (Discr));
15892 -- Tagged types cannot have defaulted discriminants, but a
15893 -- non-tagged private type with defaulted discriminants
15894 -- can have a tagged completion.
15896 elsif Is_Tagged_Type (Current_Scope)
15897 and then Comes_From_Source (N)
15900 ("discriminants of tagged type cannot have defaults",
15901 Expression (Discr));
15904 Default_Present := True;
15905 Append_Elmt (Expression (Discr), Elist);
15907 -- Tag the defining identifiers for the discriminants with
15908 -- their corresponding default expressions from the tree.
15910 Set_Discriminant_Default_Value
15911 (Defining_Identifier (Discr), Expression (Discr));
15915 Default_Not_Present := True;
15918 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
15919 -- Discr_Type but with the null-exclusion attribute
15921 if Ada_Version >= Ada_05 then
15923 -- Ada 2005 (AI-231): Static checks
15925 if Can_Never_Be_Null (Discr_Type) then
15926 Null_Exclusion_Static_Checks (Discr);
15928 elsif Is_Access_Type (Discr_Type)
15929 and then Null_Exclusion_Present (Discr)
15931 -- No need to check itypes because in their case this check
15932 -- was done at their point of creation
15934 and then not Is_Itype (Discr_Type)
15936 if Can_Never_Be_Null (Discr_Type) then
15938 ("`NOT NULL` not allowed (& already excludes null)",
15943 Set_Etype (Defining_Identifier (Discr),
15944 Create_Null_Excluding_Itype
15946 Related_Nod => Discr));
15948 -- Check for improper null exclusion if the type is otherwise
15949 -- legal for a discriminant.
15951 elsif Null_Exclusion_Present (Discr)
15952 and then Is_Discrete_Type (Discr_Type)
15955 ("null exclusion can only apply to an access type", Discr);
15958 -- Ada 2005 (AI-402): access discriminants of nonlimited types
15959 -- can't have defaults. Synchronized types, or types that are
15960 -- explicitly limited are fine, but special tests apply to derived
15961 -- types in generics: in a generic body we have to assume the
15962 -- worst, and therefore defaults are not allowed if the parent is
15963 -- a generic formal private type (see ACATS B370001).
15965 if Is_Access_Type (Discr_Type) then
15966 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
15967 or else not Default_Present
15968 or else Is_Limited_Record (Current_Scope)
15969 or else Is_Concurrent_Type (Current_Scope)
15970 or else Is_Concurrent_Record_Type (Current_Scope)
15971 or else Ekind (Current_Scope) = E_Limited_Private_Type
15973 if not Is_Derived_Type (Current_Scope)
15974 or else not Is_Generic_Type (Etype (Current_Scope))
15975 or else not In_Package_Body (Scope (Etype (Current_Scope)))
15976 or else Limited_Present
15977 (Type_Definition (Parent (Current_Scope)))
15982 Error_Msg_N ("access discriminants of nonlimited types",
15983 Expression (Discr));
15984 Error_Msg_N ("\cannot have defaults", Expression (Discr));
15987 elsif Present (Expression (Discr)) then
15989 ("(Ada 2005) access discriminants of nonlimited types",
15990 Expression (Discr));
15991 Error_Msg_N ("\cannot have defaults", Expression (Discr));
15999 -- An element list consisting of the default expressions of the
16000 -- discriminants is constructed in the above loop and used to set
16001 -- the Discriminant_Constraint attribute for the type. If an object
16002 -- is declared of this (record or task) type without any explicit
16003 -- discriminant constraint given, this element list will form the
16004 -- actual parameters for the corresponding initialization procedure
16007 Set_Discriminant_Constraint (Current_Scope, Elist);
16008 Set_Stored_Constraint (Current_Scope, No_Elist);
16010 -- Default expressions must be provided either for all or for none
16011 -- of the discriminants of a discriminant part. (RM 3.7.1)
16013 if Default_Present and then Default_Not_Present then
16015 ("incomplete specification of defaults for discriminants", N);
16018 -- The use of the name of a discriminant is not allowed in default
16019 -- expressions of a discriminant part if the specification of the
16020 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
16022 -- To detect this, the discriminant names are entered initially with an
16023 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
16024 -- attempt to use a void entity (for example in an expression that is
16025 -- type-checked) produces the error message: premature usage. Now after
16026 -- completing the semantic analysis of the discriminant part, we can set
16027 -- the Ekind of all the discriminants appropriately.
16029 Discr := First (Discriminant_Specifications (N));
16030 Discr_Number := Uint_1;
16031 while Present (Discr) loop
16032 Id := Defining_Identifier (Discr);
16033 Set_Ekind (Id, E_Discriminant);
16034 Init_Component_Location (Id);
16036 Set_Discriminant_Number (Id, Discr_Number);
16038 -- Make sure this is always set, even in illegal programs
16040 Set_Corresponding_Discriminant (Id, Empty);
16042 -- Initialize the Original_Record_Component to the entity itself.
16043 -- Inherit_Components will propagate the right value to
16044 -- discriminants in derived record types.
16046 Set_Original_Record_Component (Id, Id);
16048 -- Create the discriminal for the discriminant
16050 Build_Discriminal (Id);
16053 Discr_Number := Discr_Number + 1;
16056 Set_Has_Discriminants (Current_Scope);
16057 end Process_Discriminants;
16059 -----------------------
16060 -- Process_Full_View --
16061 -----------------------
16063 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
16064 Priv_Parent : Entity_Id;
16065 Full_Parent : Entity_Id;
16066 Full_Indic : Node_Id;
16068 procedure Collect_Implemented_Interfaces
16070 Ifaces : Elist_Id);
16071 -- Ada 2005: Gather all the interfaces that Typ directly or
16072 -- inherently implements. Duplicate entries are not added to
16073 -- the list Ifaces.
16075 ------------------------------------
16076 -- Collect_Implemented_Interfaces --
16077 ------------------------------------
16079 procedure Collect_Implemented_Interfaces
16084 Iface_Elmt : Elmt_Id;
16087 -- Abstract interfaces are only associated with tagged record types
16089 if not Is_Tagged_Type (Typ)
16090 or else not Is_Record_Type (Typ)
16095 -- Recursively climb to the ancestors
16097 if Etype (Typ) /= Typ
16099 -- Protect the frontend against wrong cyclic declarations like:
16101 -- type B is new A with private;
16102 -- type C is new A with private;
16104 -- type B is new C with null record;
16105 -- type C is new B with null record;
16107 and then Etype (Typ) /= Priv_T
16108 and then Etype (Typ) /= Full_T
16110 -- Keep separate the management of private type declarations
16112 if Ekind (Typ) = E_Record_Type_With_Private then
16114 -- Handle the following erronous case:
16115 -- type Private_Type is tagged private;
16117 -- type Private_Type is new Type_Implementing_Iface;
16119 if Present (Full_View (Typ))
16120 and then Etype (Typ) /= Full_View (Typ)
16122 if Is_Interface (Etype (Typ)) then
16123 Append_Unique_Elmt (Etype (Typ), Ifaces);
16126 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
16129 -- Non-private types
16132 if Is_Interface (Etype (Typ)) then
16133 Append_Unique_Elmt (Etype (Typ), Ifaces);
16136 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
16140 -- Handle entities in the list of abstract interfaces
16142 if Present (Interfaces (Typ)) then
16143 Iface_Elmt := First_Elmt (Interfaces (Typ));
16144 while Present (Iface_Elmt) loop
16145 Iface := Node (Iface_Elmt);
16147 pragma Assert (Is_Interface (Iface));
16149 if not Contain_Interface (Iface, Ifaces) then
16150 Append_Elmt (Iface, Ifaces);
16151 Collect_Implemented_Interfaces (Iface, Ifaces);
16154 Next_Elmt (Iface_Elmt);
16157 end Collect_Implemented_Interfaces;
16159 -- Start of processing for Process_Full_View
16162 -- First some sanity checks that must be done after semantic
16163 -- decoration of the full view and thus cannot be placed with other
16164 -- similar checks in Find_Type_Name
16166 if not Is_Limited_Type (Priv_T)
16167 and then (Is_Limited_Type (Full_T)
16168 or else Is_Limited_Composite (Full_T))
16171 ("completion of nonlimited type cannot be limited", Full_T);
16172 Explain_Limited_Type (Full_T, Full_T);
16174 elsif Is_Abstract_Type (Full_T)
16175 and then not Is_Abstract_Type (Priv_T)
16178 ("completion of nonabstract type cannot be abstract", Full_T);
16180 elsif Is_Tagged_Type (Priv_T)
16181 and then Is_Limited_Type (Priv_T)
16182 and then not Is_Limited_Type (Full_T)
16184 -- If pragma CPP_Class was applied to the private declaration
16185 -- propagate the limitedness to the full-view
16187 if Is_CPP_Class (Priv_T) then
16188 Set_Is_Limited_Record (Full_T);
16190 -- GNAT allow its own definition of Limited_Controlled to disobey
16191 -- this rule in order in ease the implementation. The next test is
16192 -- safe because Root_Controlled is defined in a private system child
16194 elsif Etype (Full_T) = Full_View (RTE (RE_Root_Controlled)) then
16195 Set_Is_Limited_Composite (Full_T);
16198 ("completion of limited tagged type must be limited", Full_T);
16201 elsif Is_Generic_Type (Priv_T) then
16202 Error_Msg_N ("generic type cannot have a completion", Full_T);
16205 -- Check that ancestor interfaces of private and full views are
16206 -- consistent. We omit this check for synchronized types because
16207 -- they are performed on the corresponding record type when frozen.
16209 if Ada_Version >= Ada_05
16210 and then Is_Tagged_Type (Priv_T)
16211 and then Is_Tagged_Type (Full_T)
16212 and then not Is_Concurrent_Type (Full_T)
16216 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
16217 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
16220 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
16221 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
16223 -- Ada 2005 (AI-251): The partial view shall be a descendant of
16224 -- an interface type if and only if the full type is descendant
16225 -- of the interface type (AARM 7.3 (7.3/2).
16227 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
16229 if Present (Iface) then
16230 Error_Msg_NE ("interface & not implemented by full type " &
16231 "(RM-2005 7.3 (7.3/2))", Priv_T, Iface);
16234 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
16236 if Present (Iface) then
16237 Error_Msg_NE ("interface & not implemented by partial view " &
16238 "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
16243 if Is_Tagged_Type (Priv_T)
16244 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
16245 and then Is_Derived_Type (Full_T)
16247 Priv_Parent := Etype (Priv_T);
16249 -- The full view of a private extension may have been transformed
16250 -- into an unconstrained derived type declaration and a subtype
16251 -- declaration (see build_derived_record_type for details).
16253 if Nkind (N) = N_Subtype_Declaration then
16254 Full_Indic := Subtype_Indication (N);
16255 Full_Parent := Etype (Base_Type (Full_T));
16257 Full_Indic := Subtype_Indication (Type_Definition (N));
16258 Full_Parent := Etype (Full_T);
16261 -- Check that the parent type of the full type is a descendant of
16262 -- the ancestor subtype given in the private extension. If either
16263 -- entity has an Etype equal to Any_Type then we had some previous
16264 -- error situation [7.3(8)].
16266 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
16269 -- Ada 2005 (AI-251): Interfaces in the full-typ can be given in
16270 -- any order. Therefore we don't have to check that its parent must
16271 -- be a descendant of the parent of the private type declaration.
16273 elsif Is_Interface (Priv_Parent)
16274 and then Is_Interface (Full_Parent)
16278 -- Ada 2005 (AI-251): If the parent of the private type declaration
16279 -- is an interface there is no need to check that it is an ancestor
16280 -- of the associated full type declaration. The required tests for
16281 -- this case are performed by Build_Derived_Record_Type.
16283 elsif not Is_Interface (Base_Type (Priv_Parent))
16284 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
16287 ("parent of full type must descend from parent"
16288 & " of private extension", Full_Indic);
16290 -- Check the rules of 7.3(10): if the private extension inherits
16291 -- known discriminants, then the full type must also inherit those
16292 -- discriminants from the same (ancestor) type, and the parent
16293 -- subtype of the full type must be constrained if and only if
16294 -- the ancestor subtype of the private extension is constrained.
16296 elsif No (Discriminant_Specifications (Parent (Priv_T)))
16297 and then not Has_Unknown_Discriminants (Priv_T)
16298 and then Has_Discriminants (Base_Type (Priv_Parent))
16301 Priv_Indic : constant Node_Id :=
16302 Subtype_Indication (Parent (Priv_T));
16304 Priv_Constr : constant Boolean :=
16305 Is_Constrained (Priv_Parent)
16307 Nkind (Priv_Indic) = N_Subtype_Indication
16308 or else Is_Constrained (Entity (Priv_Indic));
16310 Full_Constr : constant Boolean :=
16311 Is_Constrained (Full_Parent)
16313 Nkind (Full_Indic) = N_Subtype_Indication
16314 or else Is_Constrained (Entity (Full_Indic));
16316 Priv_Discr : Entity_Id;
16317 Full_Discr : Entity_Id;
16320 Priv_Discr := First_Discriminant (Priv_Parent);
16321 Full_Discr := First_Discriminant (Full_Parent);
16322 while Present (Priv_Discr) and then Present (Full_Discr) loop
16323 if Original_Record_Component (Priv_Discr) =
16324 Original_Record_Component (Full_Discr)
16326 Corresponding_Discriminant (Priv_Discr) =
16327 Corresponding_Discriminant (Full_Discr)
16334 Next_Discriminant (Priv_Discr);
16335 Next_Discriminant (Full_Discr);
16338 if Present (Priv_Discr) or else Present (Full_Discr) then
16340 ("full view must inherit discriminants of the parent type"
16341 & " used in the private extension", Full_Indic);
16343 elsif Priv_Constr and then not Full_Constr then
16345 ("parent subtype of full type must be constrained",
16348 elsif Full_Constr and then not Priv_Constr then
16350 ("parent subtype of full type must be unconstrained",
16355 -- Check the rules of 7.3(12): if a partial view has neither known
16356 -- or unknown discriminants, then the full type declaration shall
16357 -- define a definite subtype.
16359 elsif not Has_Unknown_Discriminants (Priv_T)
16360 and then not Has_Discriminants (Priv_T)
16361 and then not Is_Constrained (Full_T)
16364 ("full view must define a constrained type if partial view"
16365 & " has no discriminants", Full_T);
16368 -- ??????? Do we implement the following properly ?????
16369 -- If the ancestor subtype of a private extension has constrained
16370 -- discriminants, then the parent subtype of the full view shall
16371 -- impose a statically matching constraint on those discriminants
16375 -- For untagged types, verify that a type without discriminants
16376 -- is not completed with an unconstrained type.
16378 if not Is_Indefinite_Subtype (Priv_T)
16379 and then Is_Indefinite_Subtype (Full_T)
16381 Error_Msg_N ("full view of type must be definite subtype", Full_T);
16385 -- AI-419: verify that the use of "limited" is consistent
16388 Orig_Decl : constant Node_Id := Original_Node (N);
16391 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
16392 and then not Limited_Present (Parent (Priv_T))
16393 and then not Synchronized_Present (Parent (Priv_T))
16394 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
16396 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
16397 and then Limited_Present (Type_Definition (Orig_Decl))
16400 ("full view of non-limited extension cannot be limited", N);
16404 -- Ada 2005 (AI-443): A synchronized private extension must be
16405 -- completed by a task or protected type.
16407 if Ada_Version >= Ada_05
16408 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
16409 and then Synchronized_Present (Parent (Priv_T))
16410 and then not Is_Concurrent_Type (Full_T)
16412 Error_Msg_N ("full view of synchronized extension must " &
16413 "be synchronized type", N);
16416 -- Ada 2005 AI-363: if the full view has discriminants with
16417 -- defaults, it is illegal to declare constrained access subtypes
16418 -- whose designated type is the current type. This allows objects
16419 -- of the type that are declared in the heap to be unconstrained.
16421 if not Has_Unknown_Discriminants (Priv_T)
16422 and then not Has_Discriminants (Priv_T)
16423 and then Has_Discriminants (Full_T)
16425 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
16427 Set_Has_Constrained_Partial_View (Full_T);
16428 Set_Has_Constrained_Partial_View (Priv_T);
16431 -- Create a full declaration for all its subtypes recorded in
16432 -- Private_Dependents and swap them similarly to the base type. These
16433 -- are subtypes that have been define before the full declaration of
16434 -- the private type. We also swap the entry in Private_Dependents list
16435 -- so we can properly restore the private view on exit from the scope.
16438 Priv_Elmt : Elmt_Id;
16443 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
16444 while Present (Priv_Elmt) loop
16445 Priv := Node (Priv_Elmt);
16447 if Ekind (Priv) = E_Private_Subtype
16448 or else Ekind (Priv) = E_Limited_Private_Subtype
16449 or else Ekind (Priv) = E_Record_Subtype_With_Private
16451 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
16452 Set_Is_Itype (Full);
16453 Set_Parent (Full, Parent (Priv));
16454 Set_Associated_Node_For_Itype (Full, N);
16456 -- Now we need to complete the private subtype, but since the
16457 -- base type has already been swapped, we must also swap the
16458 -- subtypes (and thus, reverse the arguments in the call to
16459 -- Complete_Private_Subtype).
16461 Copy_And_Swap (Priv, Full);
16462 Complete_Private_Subtype (Full, Priv, Full_T, N);
16463 Replace_Elmt (Priv_Elmt, Full);
16466 Next_Elmt (Priv_Elmt);
16470 -- If the private view was tagged, copy the new primitive operations
16471 -- from the private view to the full view.
16473 if Is_Tagged_Type (Full_T) then
16475 Disp_Typ : Entity_Id;
16476 Full_List : Elist_Id;
16478 Prim_Elmt : Elmt_Id;
16479 Priv_List : Elist_Id;
16483 L : Elist_Id) return Boolean;
16484 -- Determine whether list L contains element E
16492 L : Elist_Id) return Boolean
16494 List_Elmt : Elmt_Id;
16497 List_Elmt := First_Elmt (L);
16498 while Present (List_Elmt) loop
16499 if Node (List_Elmt) = E then
16503 Next_Elmt (List_Elmt);
16509 -- Start of processing
16512 if Is_Tagged_Type (Priv_T) then
16513 Priv_List := Primitive_Operations (Priv_T);
16514 Prim_Elmt := First_Elmt (Priv_List);
16516 -- In the case of a concurrent type completing a private tagged
16517 -- type, primitives may have been declared in between the two
16518 -- views. These subprograms need to be wrapped the same way
16519 -- entries and protected procedures are handled because they
16520 -- cannot be directly shared by the two views.
16522 if Is_Concurrent_Type (Full_T) then
16524 Conc_Typ : constant Entity_Id :=
16525 Corresponding_Record_Type (Full_T);
16526 Curr_Nod : Node_Id := Parent (Conc_Typ);
16527 Wrap_Spec : Node_Id;
16530 while Present (Prim_Elmt) loop
16531 Prim := Node (Prim_Elmt);
16533 if Comes_From_Source (Prim)
16534 and then not Is_Abstract_Subprogram (Prim)
16537 Make_Subprogram_Declaration (Sloc (Prim),
16541 Obj_Typ => Conc_Typ,
16543 Parameter_Specifications (
16546 Insert_After (Curr_Nod, Wrap_Spec);
16547 Curr_Nod := Wrap_Spec;
16549 Analyze (Wrap_Spec);
16552 Next_Elmt (Prim_Elmt);
16558 -- For non-concurrent types, transfer explicit primitives, but
16559 -- omit those inherited from the parent of the private view
16560 -- since they will be re-inherited later on.
16563 Full_List := Primitive_Operations (Full_T);
16565 while Present (Prim_Elmt) loop
16566 Prim := Node (Prim_Elmt);
16568 if Comes_From_Source (Prim)
16569 and then not Contains (Prim, Full_List)
16571 Append_Elmt (Prim, Full_List);
16574 Next_Elmt (Prim_Elmt);
16578 -- Untagged private view
16581 Full_List := Primitive_Operations (Full_T);
16583 -- In this case the partial view is untagged, so here we locate
16584 -- all of the earlier primitives that need to be treated as
16585 -- dispatching (those that appear between the two views). Note
16586 -- that these additional operations must all be new operations
16587 -- (any earlier operations that override inherited operations
16588 -- of the full view will already have been inserted in the
16589 -- primitives list, marked by Check_Operation_From_Private_View
16590 -- as dispatching. Note that implicit "/=" operators are
16591 -- excluded from being added to the primitives list since they
16592 -- shouldn't be treated as dispatching (tagged "/=" is handled
16595 Prim := Next_Entity (Full_T);
16596 while Present (Prim) and then Prim /= Priv_T loop
16597 if Ekind (Prim) = E_Procedure
16599 Ekind (Prim) = E_Function
16601 Disp_Typ := Find_Dispatching_Type (Prim);
16603 if Disp_Typ = Full_T
16604 and then (Chars (Prim) /= Name_Op_Ne
16605 or else Comes_From_Source (Prim))
16607 Check_Controlling_Formals (Full_T, Prim);
16609 if not Is_Dispatching_Operation (Prim) then
16610 Append_Elmt (Prim, Full_List);
16611 Set_Is_Dispatching_Operation (Prim, True);
16612 Set_DT_Position (Prim, No_Uint);
16615 elsif Is_Dispatching_Operation (Prim)
16616 and then Disp_Typ /= Full_T
16619 -- Verify that it is not otherwise controlled by a
16620 -- formal or a return value of type T.
16622 Check_Controlling_Formals (Disp_Typ, Prim);
16626 Next_Entity (Prim);
16630 -- For the tagged case, the two views can share the same
16631 -- Primitive Operation list and the same class wide type.
16632 -- Update attributes of the class-wide type which depend on
16633 -- the full declaration.
16635 if Is_Tagged_Type (Priv_T) then
16636 Set_Primitive_Operations (Priv_T, Full_List);
16637 Set_Class_Wide_Type
16638 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
16640 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
16645 -- Ada 2005 AI 161: Check preelaboratable initialization consistency
16647 if Known_To_Have_Preelab_Init (Priv_T) then
16649 -- Case where there is a pragma Preelaborable_Initialization. We
16650 -- always allow this in predefined units, which is a bit of a kludge,
16651 -- but it means we don't have to struggle to meet the requirements in
16652 -- the RM for having Preelaborable Initialization. Otherwise we
16653 -- require that the type meets the RM rules. But we can't check that
16654 -- yet, because of the rule about overriding Ininitialize, so we
16655 -- simply set a flag that will be checked at freeze time.
16657 if not In_Predefined_Unit (Full_T) then
16658 Set_Must_Have_Preelab_Init (Full_T);
16662 -- If pragma CPP_Class was applied to the private type declaration,
16663 -- propagate it now to the full type declaration.
16665 if Is_CPP_Class (Priv_T) then
16666 Set_Is_CPP_Class (Full_T);
16667 Set_Convention (Full_T, Convention_CPP);
16670 -- If the private view has user specified stream attributes, then so has
16673 if Has_Specified_Stream_Read (Priv_T) then
16674 Set_Has_Specified_Stream_Read (Full_T);
16676 if Has_Specified_Stream_Write (Priv_T) then
16677 Set_Has_Specified_Stream_Write (Full_T);
16679 if Has_Specified_Stream_Input (Priv_T) then
16680 Set_Has_Specified_Stream_Input (Full_T);
16682 if Has_Specified_Stream_Output (Priv_T) then
16683 Set_Has_Specified_Stream_Output (Full_T);
16685 end Process_Full_View;
16687 -----------------------------------
16688 -- Process_Incomplete_Dependents --
16689 -----------------------------------
16691 procedure Process_Incomplete_Dependents
16693 Full_T : Entity_Id;
16696 Inc_Elmt : Elmt_Id;
16697 Priv_Dep : Entity_Id;
16698 New_Subt : Entity_Id;
16700 Disc_Constraint : Elist_Id;
16703 if No (Private_Dependents (Inc_T)) then
16707 -- Itypes that may be generated by the completion of an incomplete
16708 -- subtype are not used by the back-end and not attached to the tree.
16709 -- They are created only for constraint-checking purposes.
16711 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
16712 while Present (Inc_Elmt) loop
16713 Priv_Dep := Node (Inc_Elmt);
16715 if Ekind (Priv_Dep) = E_Subprogram_Type then
16717 -- An Access_To_Subprogram type may have a return type or a
16718 -- parameter type that is incomplete. Replace with the full view.
16720 if Etype (Priv_Dep) = Inc_T then
16721 Set_Etype (Priv_Dep, Full_T);
16725 Formal : Entity_Id;
16728 Formal := First_Formal (Priv_Dep);
16729 while Present (Formal) loop
16730 if Etype (Formal) = Inc_T then
16731 Set_Etype (Formal, Full_T);
16734 Next_Formal (Formal);
16738 elsif Is_Overloadable (Priv_Dep) then
16740 -- A protected operation is never dispatching: only its
16741 -- wrapper operation (which has convention Ada) is.
16743 if Is_Tagged_Type (Full_T)
16744 and then Convention (Priv_Dep) /= Convention_Protected
16747 -- Subprogram has an access parameter whose designated type
16748 -- was incomplete. Reexamine declaration now, because it may
16749 -- be a primitive operation of the full type.
16751 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
16752 Set_Is_Dispatching_Operation (Priv_Dep);
16753 Check_Controlling_Formals (Full_T, Priv_Dep);
16756 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
16758 -- Can happen during processing of a body before the completion
16759 -- of a TA type. Ignore, because spec is also on dependent list.
16763 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
16764 -- corresponding subtype of the full view.
16766 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
16767 Set_Subtype_Indication
16768 (Parent (Priv_Dep), New_Reference_To (Full_T, Sloc (Priv_Dep)));
16769 Set_Etype (Priv_Dep, Full_T);
16770 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
16771 Set_Analyzed (Parent (Priv_Dep), False);
16773 -- Reanalyze the declaration, suppressing the call to
16774 -- Enter_Name to avoid duplicate names.
16776 Analyze_Subtype_Declaration
16777 (N => Parent (Priv_Dep),
16780 -- Dependent is a subtype
16783 -- We build a new subtype indication using the full view of the
16784 -- incomplete parent. The discriminant constraints have been
16785 -- elaborated already at the point of the subtype declaration.
16787 New_Subt := Create_Itype (E_Void, N);
16789 if Has_Discriminants (Full_T) then
16790 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
16792 Disc_Constraint := No_Elist;
16795 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
16796 Set_Full_View (Priv_Dep, New_Subt);
16799 Next_Elmt (Inc_Elmt);
16801 end Process_Incomplete_Dependents;
16803 --------------------------------
16804 -- Process_Range_Expr_In_Decl --
16805 --------------------------------
16807 procedure Process_Range_Expr_In_Decl
16810 Check_List : List_Id := Empty_List;
16811 R_Check_Off : Boolean := False)
16814 R_Checks : Check_Result;
16815 Type_Decl : Node_Id;
16816 Def_Id : Entity_Id;
16819 Analyze_And_Resolve (R, Base_Type (T));
16821 if Nkind (R) = N_Range then
16822 Lo := Low_Bound (R);
16823 Hi := High_Bound (R);
16825 -- We need to ensure validity of the bounds here, because if we
16826 -- go ahead and do the expansion, then the expanded code will get
16827 -- analyzed with range checks suppressed and we miss the check.
16829 Validity_Check_Range (R);
16831 -- If there were errors in the declaration, try and patch up some
16832 -- common mistakes in the bounds. The cases handled are literals
16833 -- which are Integer where the expected type is Real and vice versa.
16834 -- These corrections allow the compilation process to proceed further
16835 -- along since some basic assumptions of the format of the bounds
16838 if Etype (R) = Any_Type then
16840 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
16842 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
16844 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
16846 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
16848 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
16850 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
16852 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
16854 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
16861 -- If the bounds of the range have been mistakenly given as string
16862 -- literals (perhaps in place of character literals), then an error
16863 -- has already been reported, but we rewrite the string literal as a
16864 -- bound of the range's type to avoid blowups in later processing
16865 -- that looks at static values.
16867 if Nkind (Lo) = N_String_Literal then
16869 Make_Attribute_Reference (Sloc (Lo),
16870 Attribute_Name => Name_First,
16871 Prefix => New_Reference_To (T, Sloc (Lo))));
16872 Analyze_And_Resolve (Lo);
16875 if Nkind (Hi) = N_String_Literal then
16877 Make_Attribute_Reference (Sloc (Hi),
16878 Attribute_Name => Name_First,
16879 Prefix => New_Reference_To (T, Sloc (Hi))));
16880 Analyze_And_Resolve (Hi);
16883 -- If bounds aren't scalar at this point then exit, avoiding
16884 -- problems with further processing of the range in this procedure.
16886 if not Is_Scalar_Type (Etype (Lo)) then
16890 -- Resolve (actually Sem_Eval) has checked that the bounds are in
16891 -- then range of the base type. Here we check whether the bounds
16892 -- are in the range of the subtype itself. Note that if the bounds
16893 -- represent the null range the Constraint_Error exception should
16896 -- ??? The following code should be cleaned up as follows
16898 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
16899 -- is done in the call to Range_Check (R, T); below
16901 -- 2. The use of R_Check_Off should be investigated and possibly
16902 -- removed, this would clean up things a bit.
16904 if Is_Null_Range (Lo, Hi) then
16908 -- Capture values of bounds and generate temporaries for them
16909 -- if needed, before applying checks, since checks may cause
16910 -- duplication of the expression without forcing evaluation.
16912 if Expander_Active then
16913 Force_Evaluation (Lo);
16914 Force_Evaluation (Hi);
16917 -- We use a flag here instead of suppressing checks on the
16918 -- type because the type we check against isn't necessarily
16919 -- the place where we put the check.
16921 if not R_Check_Off then
16922 R_Checks := Get_Range_Checks (R, T);
16924 -- Look up tree to find an appropriate insertion point.
16925 -- This seems really junk code, and very brittle, couldn't
16926 -- we just use an insert actions call of some kind ???
16928 Type_Decl := Parent (R);
16929 while Present (Type_Decl) and then not
16930 (Nkind_In (Type_Decl, N_Full_Type_Declaration,
16931 N_Subtype_Declaration,
16933 N_Task_Type_Declaration)
16935 Nkind_In (Type_Decl, N_Single_Task_Declaration,
16936 N_Protected_Type_Declaration,
16937 N_Single_Protected_Declaration))
16939 Type_Decl := Parent (Type_Decl);
16942 -- Why would Type_Decl not be present??? Without this test,
16943 -- short regression tests fail.
16945 if Present (Type_Decl) then
16947 -- Case of loop statement (more comments ???)
16949 if Nkind (Type_Decl) = N_Loop_Statement then
16954 Indic := Parent (R);
16955 while Present (Indic)
16956 and then Nkind (Indic) /= N_Subtype_Indication
16958 Indic := Parent (Indic);
16961 if Present (Indic) then
16962 Def_Id := Etype (Subtype_Mark (Indic));
16964 Insert_Range_Checks
16970 Do_Before => True);
16974 -- All other cases (more comments ???)
16977 Def_Id := Defining_Identifier (Type_Decl);
16979 if (Ekind (Def_Id) = E_Record_Type
16980 and then Depends_On_Discriminant (R))
16982 (Ekind (Def_Id) = E_Protected_Type
16983 and then Has_Discriminants (Def_Id))
16985 Append_Range_Checks
16986 (R_Checks, Check_List, Def_Id, Sloc (Type_Decl), R);
16989 Insert_Range_Checks
16990 (R_Checks, Type_Decl, Def_Id, Sloc (Type_Decl), R);
16998 elsif Expander_Active then
16999 Get_Index_Bounds (R, Lo, Hi);
17000 Force_Evaluation (Lo);
17001 Force_Evaluation (Hi);
17003 end Process_Range_Expr_In_Decl;
17005 --------------------------------------
17006 -- Process_Real_Range_Specification --
17007 --------------------------------------
17009 procedure Process_Real_Range_Specification (Def : Node_Id) is
17010 Spec : constant Node_Id := Real_Range_Specification (Def);
17013 Err : Boolean := False;
17015 procedure Analyze_Bound (N : Node_Id);
17016 -- Analyze and check one bound
17018 -------------------
17019 -- Analyze_Bound --
17020 -------------------
17022 procedure Analyze_Bound (N : Node_Id) is
17024 Analyze_And_Resolve (N, Any_Real);
17026 if not Is_OK_Static_Expression (N) then
17027 Flag_Non_Static_Expr
17028 ("bound in real type definition is not static!", N);
17033 -- Start of processing for Process_Real_Range_Specification
17036 if Present (Spec) then
17037 Lo := Low_Bound (Spec);
17038 Hi := High_Bound (Spec);
17039 Analyze_Bound (Lo);
17040 Analyze_Bound (Hi);
17042 -- If error, clear away junk range specification
17045 Set_Real_Range_Specification (Def, Empty);
17048 end Process_Real_Range_Specification;
17050 ---------------------
17051 -- Process_Subtype --
17052 ---------------------
17054 function Process_Subtype
17056 Related_Nod : Node_Id;
17057 Related_Id : Entity_Id := Empty;
17058 Suffix : Character := ' ') return Entity_Id
17061 Def_Id : Entity_Id;
17062 Error_Node : Node_Id;
17063 Full_View_Id : Entity_Id;
17064 Subtype_Mark_Id : Entity_Id;
17066 May_Have_Null_Exclusion : Boolean;
17068 procedure Check_Incomplete (T : Entity_Id);
17069 -- Called to verify that an incomplete type is not used prematurely
17071 ----------------------
17072 -- Check_Incomplete --
17073 ----------------------
17075 procedure Check_Incomplete (T : Entity_Id) is
17077 -- Ada 2005 (AI-412): Incomplete subtypes are legal
17079 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
17081 not (Ada_Version >= Ada_05
17083 (Nkind (Parent (T)) = N_Subtype_Declaration
17085 (Nkind (Parent (T)) = N_Subtype_Indication
17086 and then Nkind (Parent (Parent (T))) =
17087 N_Subtype_Declaration)))
17089 Error_Msg_N ("invalid use of type before its full declaration", T);
17091 end Check_Incomplete;
17093 -- Start of processing for Process_Subtype
17096 -- Case of no constraints present
17098 if Nkind (S) /= N_Subtype_Indication then
17100 Check_Incomplete (S);
17103 -- Ada 2005 (AI-231): Static check
17105 if Ada_Version >= Ada_05
17106 and then Present (P)
17107 and then Null_Exclusion_Present (P)
17108 and then Nkind (P) /= N_Access_To_Object_Definition
17109 and then not Is_Access_Type (Entity (S))
17111 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
17114 -- The following is ugly, can't we have a range or even a flag???
17116 May_Have_Null_Exclusion :=
17117 Nkind_In (P, N_Access_Definition,
17118 N_Access_Function_Definition,
17119 N_Access_Procedure_Definition,
17120 N_Access_To_Object_Definition,
17122 N_Component_Definition)
17124 Nkind_In (P, N_Derived_Type_Definition,
17125 N_Discriminant_Specification,
17126 N_Formal_Object_Declaration,
17127 N_Object_Declaration,
17128 N_Object_Renaming_Declaration,
17129 N_Parameter_Specification,
17130 N_Subtype_Declaration);
17132 -- Create an Itype that is a duplicate of Entity (S) but with the
17133 -- null-exclusion attribute
17135 if May_Have_Null_Exclusion
17136 and then Is_Access_Type (Entity (S))
17137 and then Null_Exclusion_Present (P)
17139 -- No need to check the case of an access to object definition.
17140 -- It is correct to define double not-null pointers.
17143 -- type Not_Null_Int_Ptr is not null access Integer;
17144 -- type Acc is not null access Not_Null_Int_Ptr;
17146 and then Nkind (P) /= N_Access_To_Object_Definition
17148 if Can_Never_Be_Null (Entity (S)) then
17149 case Nkind (Related_Nod) is
17150 when N_Full_Type_Declaration =>
17151 if Nkind (Type_Definition (Related_Nod))
17152 in N_Array_Type_Definition
17156 (Component_Definition
17157 (Type_Definition (Related_Nod)));
17160 Subtype_Indication (Type_Definition (Related_Nod));
17163 when N_Subtype_Declaration =>
17164 Error_Node := Subtype_Indication (Related_Nod);
17166 when N_Object_Declaration =>
17167 Error_Node := Object_Definition (Related_Nod);
17169 when N_Component_Declaration =>
17171 Subtype_Indication (Component_Definition (Related_Nod));
17173 when N_Allocator =>
17174 Error_Node := Expression (Related_Nod);
17177 pragma Assert (False);
17178 Error_Node := Related_Nod;
17182 ("`NOT NULL` not allowed (& already excludes null)",
17188 Create_Null_Excluding_Itype
17190 Related_Nod => P));
17191 Set_Entity (S, Etype (S));
17196 -- Case of constraint present, so that we have an N_Subtype_Indication
17197 -- node (this node is created only if constraints are present).
17200 Find_Type (Subtype_Mark (S));
17202 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
17204 (Nkind (Parent (S)) = N_Subtype_Declaration
17205 and then Is_Itype (Defining_Identifier (Parent (S))))
17207 Check_Incomplete (Subtype_Mark (S));
17211 Subtype_Mark_Id := Entity (Subtype_Mark (S));
17213 -- Explicit subtype declaration case
17215 if Nkind (P) = N_Subtype_Declaration then
17216 Def_Id := Defining_Identifier (P);
17218 -- Explicit derived type definition case
17220 elsif Nkind (P) = N_Derived_Type_Definition then
17221 Def_Id := Defining_Identifier (Parent (P));
17223 -- Implicit case, the Def_Id must be created as an implicit type.
17224 -- The one exception arises in the case of concurrent types, array
17225 -- and access types, where other subsidiary implicit types may be
17226 -- created and must appear before the main implicit type. In these
17227 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
17228 -- has not yet been called to create Def_Id.
17231 if Is_Array_Type (Subtype_Mark_Id)
17232 or else Is_Concurrent_Type (Subtype_Mark_Id)
17233 or else Is_Access_Type (Subtype_Mark_Id)
17237 -- For the other cases, we create a new unattached Itype,
17238 -- and set the indication to ensure it gets attached later.
17242 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
17246 -- If the kind of constraint is invalid for this kind of type,
17247 -- then give an error, and then pretend no constraint was given.
17249 if not Is_Valid_Constraint_Kind
17250 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
17253 ("incorrect constraint for this kind of type", Constraint (S));
17255 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
17257 -- Set Ekind of orphan itype, to prevent cascaded errors
17259 if Present (Def_Id) then
17260 Set_Ekind (Def_Id, Ekind (Any_Type));
17263 -- Make recursive call, having got rid of the bogus constraint
17265 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
17268 -- Remaining processing depends on type
17270 case Ekind (Subtype_Mark_Id) is
17271 when Access_Kind =>
17272 Constrain_Access (Def_Id, S, Related_Nod);
17275 and then Is_Itype (Designated_Type (Def_Id))
17276 and then Nkind (Related_Nod) = N_Subtype_Declaration
17277 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
17279 Build_Itype_Reference
17280 (Designated_Type (Def_Id), Related_Nod);
17284 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
17286 when Decimal_Fixed_Point_Kind =>
17287 Constrain_Decimal (Def_Id, S);
17289 when Enumeration_Kind =>
17290 Constrain_Enumeration (Def_Id, S);
17292 when Ordinary_Fixed_Point_Kind =>
17293 Constrain_Ordinary_Fixed (Def_Id, S);
17296 Constrain_Float (Def_Id, S);
17298 when Integer_Kind =>
17299 Constrain_Integer (Def_Id, S);
17301 when E_Record_Type |
17304 E_Incomplete_Type =>
17305 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
17307 if Ekind (Def_Id) = E_Incomplete_Type then
17308 Set_Private_Dependents (Def_Id, New_Elmt_List);
17311 when Private_Kind =>
17312 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
17313 Set_Private_Dependents (Def_Id, New_Elmt_List);
17315 -- In case of an invalid constraint prevent further processing
17316 -- since the type constructed is missing expected fields.
17318 if Etype (Def_Id) = Any_Type then
17322 -- If the full view is that of a task with discriminants,
17323 -- we must constrain both the concurrent type and its
17324 -- corresponding record type. Otherwise we will just propagate
17325 -- the constraint to the full view, if available.
17327 if Present (Full_View (Subtype_Mark_Id))
17328 and then Has_Discriminants (Subtype_Mark_Id)
17329 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
17332 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
17334 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
17335 Constrain_Concurrent (Full_View_Id, S,
17336 Related_Nod, Related_Id, Suffix);
17337 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
17338 Set_Full_View (Def_Id, Full_View_Id);
17340 -- Introduce an explicit reference to the private subtype,
17341 -- to prevent scope anomalies in gigi if first use appears
17342 -- in a nested context, e.g. a later function body.
17343 -- Should this be generated in other contexts than a full
17344 -- type declaration?
17346 if Is_Itype (Def_Id)
17348 Nkind (Parent (P)) = N_Full_Type_Declaration
17350 Build_Itype_Reference (Def_Id, Parent (P));
17354 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
17357 when Concurrent_Kind =>
17358 Constrain_Concurrent (Def_Id, S,
17359 Related_Nod, Related_Id, Suffix);
17362 Error_Msg_N ("invalid subtype mark in subtype indication", S);
17365 -- Size and Convention are always inherited from the base type
17367 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
17368 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
17372 end Process_Subtype;
17374 ---------------------------------------
17375 -- Check_Anonymous_Access_Components --
17376 ---------------------------------------
17378 procedure Check_Anonymous_Access_Components
17379 (Typ_Decl : Node_Id;
17382 Comp_List : Node_Id)
17384 Loc : constant Source_Ptr := Sloc (Typ_Decl);
17385 Anon_Access : Entity_Id;
17388 Comp_Def : Node_Id;
17390 Type_Def : Node_Id;
17392 procedure Build_Incomplete_Type_Declaration;
17393 -- If the record type contains components that include an access to the
17394 -- current record, then create an incomplete type declaration for the
17395 -- record, to be used as the designated type of the anonymous access.
17396 -- This is done only once, and only if there is no previous partial
17397 -- view of the type.
17399 function Designates_T (Subt : Node_Id) return Boolean;
17400 -- Check whether a node designates the enclosing record type, or 'Class
17403 function Mentions_T (Acc_Def : Node_Id) return Boolean;
17404 -- Check whether an access definition includes a reference to
17405 -- the enclosing record type. The reference can be a subtype mark
17406 -- in the access definition itself, a 'Class attribute reference, or
17407 -- recursively a reference appearing in a parameter specification
17408 -- or result definition of an access_to_subprogram definition.
17410 --------------------------------------
17411 -- Build_Incomplete_Type_Declaration --
17412 --------------------------------------
17414 procedure Build_Incomplete_Type_Declaration is
17419 -- Is_Tagged indicates whether the type is tagged. It is tagged if
17420 -- it's "is new ... with record" or else "is tagged record ...".
17422 Is_Tagged : constant Boolean :=
17423 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
17426 (Record_Extension_Part (Type_Definition (Typ_Decl))))
17428 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
17429 and then Tagged_Present (Type_Definition (Typ_Decl)));
17432 -- If there is a previous partial view, no need to create a new one
17433 -- If the partial view, given by Prev, is incomplete, If Prev is
17434 -- a private declaration, full declaration is flagged accordingly.
17436 if Prev /= Typ then
17438 Make_Class_Wide_Type (Prev);
17439 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
17440 Set_Etype (Class_Wide_Type (Typ), Typ);
17445 elsif Has_Private_Declaration (Typ) then
17447 -- If we refer to T'Class inside T, and T is the completion of a
17448 -- private type, then we need to make sure the class-wide type
17452 Make_Class_Wide_Type (Typ);
17457 -- If there was a previous anonymous access type, the incomplete
17458 -- type declaration will have been created already.
17460 elsif Present (Current_Entity (Typ))
17461 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
17462 and then Full_View (Current_Entity (Typ)) = Typ
17467 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
17468 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
17470 -- Type has already been inserted into the current scope.
17471 -- Remove it, and add incomplete declaration for type, so
17472 -- that subsequent anonymous access types can use it.
17473 -- The entity is unchained from the homonym list and from
17474 -- immediate visibility. After analysis, the entity in the
17475 -- incomplete declaration becomes immediately visible in the
17476 -- record declaration that follows.
17478 H := Current_Entity (Typ);
17481 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
17484 and then Homonym (H) /= Typ
17486 H := Homonym (Typ);
17489 Set_Homonym (H, Homonym (Typ));
17492 Insert_Before (Typ_Decl, Decl);
17494 Set_Full_View (Inc_T, Typ);
17497 -- Create a common class-wide type for both views, and set
17498 -- the Etype of the class-wide type to the full view.
17500 Make_Class_Wide_Type (Inc_T);
17501 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
17502 Set_Etype (Class_Wide_Type (Typ), Typ);
17505 end Build_Incomplete_Type_Declaration;
17511 function Designates_T (Subt : Node_Id) return Boolean is
17512 Type_Id : constant Name_Id := Chars (Typ);
17514 function Names_T (Nam : Node_Id) return Boolean;
17515 -- The record type has not been introduced in the current scope
17516 -- yet, so we must examine the name of the type itself, either
17517 -- an identifier T, or an expanded name of the form P.T, where
17518 -- P denotes the current scope.
17524 function Names_T (Nam : Node_Id) return Boolean is
17526 if Nkind (Nam) = N_Identifier then
17527 return Chars (Nam) = Type_Id;
17529 elsif Nkind (Nam) = N_Selected_Component then
17530 if Chars (Selector_Name (Nam)) = Type_Id then
17531 if Nkind (Prefix (Nam)) = N_Identifier then
17532 return Chars (Prefix (Nam)) = Chars (Current_Scope);
17534 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
17535 return Chars (Selector_Name (Prefix (Nam))) =
17536 Chars (Current_Scope);
17550 -- Start of processing for Designates_T
17553 if Nkind (Subt) = N_Identifier then
17554 return Chars (Subt) = Type_Id;
17556 -- Reference can be through an expanded name which has not been
17557 -- analyzed yet, and which designates enclosing scopes.
17559 elsif Nkind (Subt) = N_Selected_Component then
17560 if Names_T (Subt) then
17563 -- Otherwise it must denote an entity that is already visible.
17564 -- The access definition may name a subtype of the enclosing
17565 -- type, if there is a previous incomplete declaration for it.
17568 Find_Selected_Component (Subt);
17570 Is_Entity_Name (Subt)
17571 and then Scope (Entity (Subt)) = Current_Scope
17573 (Chars (Base_Type (Entity (Subt))) = Type_Id
17575 (Is_Class_Wide_Type (Entity (Subt))
17577 Chars (Etype (Base_Type (Entity (Subt)))) =
17581 -- A reference to the current type may appear as the prefix of
17582 -- a 'Class attribute.
17584 elsif Nkind (Subt) = N_Attribute_Reference
17585 and then Attribute_Name (Subt) = Name_Class
17587 return Names_T (Prefix (Subt));
17598 function Mentions_T (Acc_Def : Node_Id) return Boolean is
17599 Param_Spec : Node_Id;
17601 Acc_Subprg : constant Node_Id :=
17602 Access_To_Subprogram_Definition (Acc_Def);
17605 if No (Acc_Subprg) then
17606 return Designates_T (Subtype_Mark (Acc_Def));
17609 -- Component is an access_to_subprogram: examine its formals,
17610 -- and result definition in the case of an access_to_function.
17612 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
17613 while Present (Param_Spec) loop
17614 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
17615 and then Mentions_T (Parameter_Type (Param_Spec))
17619 elsif Designates_T (Parameter_Type (Param_Spec)) then
17626 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
17627 if Nkind (Result_Definition (Acc_Subprg)) =
17628 N_Access_Definition
17630 return Mentions_T (Result_Definition (Acc_Subprg));
17632 return Designates_T (Result_Definition (Acc_Subprg));
17639 -- Start of processing for Check_Anonymous_Access_Components
17642 if No (Comp_List) then
17646 Comp := First (Component_Items (Comp_List));
17647 while Present (Comp) loop
17648 if Nkind (Comp) = N_Component_Declaration
17650 (Access_Definition (Component_Definition (Comp)))
17652 Mentions_T (Access_Definition (Component_Definition (Comp)))
17654 Comp_Def := Component_Definition (Comp);
17656 Access_To_Subprogram_Definition
17657 (Access_Definition (Comp_Def));
17659 Build_Incomplete_Type_Declaration;
17661 Make_Defining_Identifier (Loc,
17662 Chars => New_Internal_Name ('S'));
17664 -- Create a declaration for the anonymous access type: either
17665 -- an access_to_object or an access_to_subprogram.
17667 if Present (Acc_Def) then
17668 if Nkind (Acc_Def) = N_Access_Function_Definition then
17670 Make_Access_Function_Definition (Loc,
17671 Parameter_Specifications =>
17672 Parameter_Specifications (Acc_Def),
17673 Result_Definition => Result_Definition (Acc_Def));
17676 Make_Access_Procedure_Definition (Loc,
17677 Parameter_Specifications =>
17678 Parameter_Specifications (Acc_Def));
17683 Make_Access_To_Object_Definition (Loc,
17684 Subtype_Indication =>
17687 (Access_Definition (Comp_Def))));
17689 Set_Constant_Present
17690 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
17692 (Type_Def, All_Present (Access_Definition (Comp_Def)));
17695 Set_Null_Exclusion_Present
17697 Null_Exclusion_Present (Access_Definition (Comp_Def)));
17700 Make_Full_Type_Declaration (Loc,
17701 Defining_Identifier => Anon_Access,
17702 Type_Definition => Type_Def);
17704 Insert_Before (Typ_Decl, Decl);
17707 -- If an access to object, Preserve entity of designated type,
17708 -- for ASIS use, before rewriting the component definition.
17710 if No (Acc_Def) then
17715 Desig := Entity (Subtype_Indication (Type_Def));
17717 -- If the access definition is to the current record,
17718 -- the visible entity at this point is an incomplete
17719 -- type. Retrieve the full view to simplify ASIS queries
17721 if Ekind (Desig) = E_Incomplete_Type then
17722 Desig := Full_View (Desig);
17726 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
17731 Make_Component_Definition (Loc,
17732 Subtype_Indication =>
17733 New_Occurrence_Of (Anon_Access, Loc)));
17735 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
17736 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
17738 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
17741 Set_Is_Local_Anonymous_Access (Anon_Access);
17747 if Present (Variant_Part (Comp_List)) then
17751 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
17752 while Present (V) loop
17753 Check_Anonymous_Access_Components
17754 (Typ_Decl, Typ, Prev, Component_List (V));
17755 Next_Non_Pragma (V);
17759 end Check_Anonymous_Access_Components;
17761 --------------------------------
17762 -- Preanalyze_Spec_Expression --
17763 --------------------------------
17765 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
17766 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
17768 In_Spec_Expression := True;
17769 Preanalyze_And_Resolve (N, T);
17770 In_Spec_Expression := Save_In_Spec_Expression;
17771 end Preanalyze_Spec_Expression;
17773 -----------------------------
17774 -- Record_Type_Declaration --
17775 -----------------------------
17777 procedure Record_Type_Declaration
17782 Def : constant Node_Id := Type_Definition (N);
17783 Is_Tagged : Boolean;
17784 Tag_Comp : Entity_Id;
17787 -- These flags must be initialized before calling Process_Discriminants
17788 -- because this routine makes use of them.
17790 Set_Ekind (T, E_Record_Type);
17792 Init_Size_Align (T);
17793 Set_Interfaces (T, No_Elist);
17794 Set_Stored_Constraint (T, No_Elist);
17798 if Ada_Version < Ada_05
17799 or else not Interface_Present (Def)
17801 -- The flag Is_Tagged_Type might have already been set by
17802 -- Find_Type_Name if it detected an error for declaration T. This
17803 -- arises in the case of private tagged types where the full view
17804 -- omits the word tagged.
17807 Tagged_Present (Def)
17808 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
17810 Set_Is_Tagged_Type (T, Is_Tagged);
17811 Set_Is_Limited_Record (T, Limited_Present (Def));
17813 -- Type is abstract if full declaration carries keyword, or if
17814 -- previous partial view did.
17816 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
17817 or else Abstract_Present (Def));
17821 Analyze_Interface_Declaration (T, Def);
17823 if Present (Discriminant_Specifications (N)) then
17825 ("interface types cannot have discriminants",
17826 Defining_Identifier
17827 (First (Discriminant_Specifications (N))));
17831 -- First pass: if there are self-referential access components,
17832 -- create the required anonymous access type declarations, and if
17833 -- need be an incomplete type declaration for T itself.
17835 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
17837 if Ada_Version >= Ada_05
17838 and then Present (Interface_List (Def))
17840 Check_Interfaces (N, Def);
17843 Ifaces_List : Elist_Id;
17846 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
17847 -- already in the parents.
17851 Ifaces_List => Ifaces_List,
17852 Exclude_Parents => True);
17854 Set_Interfaces (T, Ifaces_List);
17858 -- Records constitute a scope for the component declarations within.
17859 -- The scope is created prior to the processing of these declarations.
17860 -- Discriminants are processed first, so that they are visible when
17861 -- processing the other components. The Ekind of the record type itself
17862 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
17864 -- Enter record scope
17868 -- If an incomplete or private type declaration was already given for
17869 -- the type, then this scope already exists, and the discriminants have
17870 -- been declared within. We must verify that the full declaration
17871 -- matches the incomplete one.
17873 Check_Or_Process_Discriminants (N, T, Prev);
17875 Set_Is_Constrained (T, not Has_Discriminants (T));
17876 Set_Has_Delayed_Freeze (T, True);
17878 -- For tagged types add a manually analyzed component corresponding
17879 -- to the component _tag, the corresponding piece of tree will be
17880 -- expanded as part of the freezing actions if it is not a CPP_Class.
17884 -- Do not add the tag unless we are in expansion mode
17886 if Expander_Active then
17887 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
17888 Enter_Name (Tag_Comp);
17890 Set_Ekind (Tag_Comp, E_Component);
17891 Set_Is_Tag (Tag_Comp);
17892 Set_Is_Aliased (Tag_Comp);
17893 Set_Etype (Tag_Comp, RTE (RE_Tag));
17894 Set_DT_Entry_Count (Tag_Comp, No_Uint);
17895 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
17896 Init_Component_Location (Tag_Comp);
17898 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
17899 -- implemented interfaces.
17901 if Has_Interfaces (T) then
17902 Add_Interface_Tag_Components (N, T);
17906 Make_Class_Wide_Type (T);
17907 Set_Primitive_Operations (T, New_Elmt_List);
17910 -- We must suppress range checks when processing the components
17911 -- of a record in the presence of discriminants, since we don't
17912 -- want spurious checks to be generated during their analysis, but
17913 -- must reset the Suppress_Range_Checks flags after having processed
17914 -- the record definition.
17916 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
17917 -- couldn't we just use the normal range check suppression method here.
17918 -- That would seem cleaner ???
17920 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
17921 Set_Kill_Range_Checks (T, True);
17922 Record_Type_Definition (Def, Prev);
17923 Set_Kill_Range_Checks (T, False);
17925 Record_Type_Definition (Def, Prev);
17928 -- Exit from record scope
17932 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
17933 -- the implemented interfaces and associate them an aliased entity.
17936 and then not Is_Empty_List (Interface_List (Def))
17938 Derive_Progenitor_Subprograms (T, T);
17940 end Record_Type_Declaration;
17942 ----------------------------
17943 -- Record_Type_Definition --
17944 ----------------------------
17946 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
17947 Component : Entity_Id;
17948 Ctrl_Components : Boolean := False;
17949 Final_Storage_Only : Boolean;
17953 if Ekind (Prev_T) = E_Incomplete_Type then
17954 T := Full_View (Prev_T);
17959 Final_Storage_Only := not Is_Controlled (T);
17961 -- Ada 2005: check whether an explicit Limited is present in a derived
17962 -- type declaration.
17964 if Nkind (Parent (Def)) = N_Derived_Type_Definition
17965 and then Limited_Present (Parent (Def))
17967 Set_Is_Limited_Record (T);
17970 -- If the component list of a record type is defined by the reserved
17971 -- word null and there is no discriminant part, then the record type has
17972 -- no components and all records of the type are null records (RM 3.7)
17973 -- This procedure is also called to process the extension part of a
17974 -- record extension, in which case the current scope may have inherited
17978 or else No (Component_List (Def))
17979 or else Null_Present (Component_List (Def))
17984 Analyze_Declarations (Component_Items (Component_List (Def)));
17986 if Present (Variant_Part (Component_List (Def))) then
17987 Analyze (Variant_Part (Component_List (Def)));
17991 -- After completing the semantic analysis of the record definition,
17992 -- record components, both new and inherited, are accessible. Set their
17993 -- kind accordingly. Exclude malformed itypes from illegal declarations,
17994 -- whose Ekind may be void.
17996 Component := First_Entity (Current_Scope);
17997 while Present (Component) loop
17998 if Ekind (Component) = E_Void
17999 and then not Is_Itype (Component)
18001 Set_Ekind (Component, E_Component);
18002 Init_Component_Location (Component);
18005 if Has_Task (Etype (Component)) then
18009 if Ekind (Component) /= E_Component then
18012 elsif Has_Controlled_Component (Etype (Component))
18013 or else (Chars (Component) /= Name_uParent
18014 and then Is_Controlled (Etype (Component)))
18016 Set_Has_Controlled_Component (T, True);
18017 Final_Storage_Only :=
18019 and then Finalize_Storage_Only (Etype (Component));
18020 Ctrl_Components := True;
18023 Next_Entity (Component);
18026 -- A Type is Finalize_Storage_Only only if all its controlled components
18029 if Ctrl_Components then
18030 Set_Finalize_Storage_Only (T, Final_Storage_Only);
18033 -- Place reference to end record on the proper entity, which may
18034 -- be a partial view.
18036 if Present (Def) then
18037 Process_End_Label (Def, 'e', Prev_T);
18039 end Record_Type_Definition;
18041 ------------------------
18042 -- Replace_Components --
18043 ------------------------
18045 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
18046 function Process (N : Node_Id) return Traverse_Result;
18052 function Process (N : Node_Id) return Traverse_Result is
18056 if Nkind (N) = N_Discriminant_Specification then
18057 Comp := First_Discriminant (Typ);
18058 while Present (Comp) loop
18059 if Chars (Comp) = Chars (Defining_Identifier (N)) then
18060 Set_Defining_Identifier (N, Comp);
18064 Next_Discriminant (Comp);
18067 elsif Nkind (N) = N_Component_Declaration then
18068 Comp := First_Component (Typ);
18069 while Present (Comp) loop
18070 if Chars (Comp) = Chars (Defining_Identifier (N)) then
18071 Set_Defining_Identifier (N, Comp);
18075 Next_Component (Comp);
18082 procedure Replace is new Traverse_Proc (Process);
18084 -- Start of processing for Replace_Components
18088 end Replace_Components;
18090 -------------------------------
18091 -- Set_Completion_Referenced --
18092 -------------------------------
18094 procedure Set_Completion_Referenced (E : Entity_Id) is
18096 -- If in main unit, mark entity that is a completion as referenced,
18097 -- warnings go on the partial view when needed.
18099 if In_Extended_Main_Source_Unit (E) then
18100 Set_Referenced (E);
18102 end Set_Completion_Referenced;
18104 ---------------------
18105 -- Set_Fixed_Range --
18106 ---------------------
18108 -- The range for fixed-point types is complicated by the fact that we
18109 -- do not know the exact end points at the time of the declaration. This
18110 -- is true for three reasons:
18112 -- A size clause may affect the fudging of the end-points
18113 -- A small clause may affect the values of the end-points
18114 -- We try to include the end-points if it does not affect the size
18116 -- This means that the actual end-points must be established at the point
18117 -- when the type is frozen. Meanwhile, we first narrow the range as
18118 -- permitted (so that it will fit if necessary in a small specified size),
18119 -- and then build a range subtree with these narrowed bounds.
18121 -- Set_Fixed_Range constructs the range from real literal values, and sets
18122 -- the range as the Scalar_Range of the given fixed-point type entity.
18124 -- The parent of this range is set to point to the entity so that it is
18125 -- properly hooked into the tree (unlike normal Scalar_Range entries for
18126 -- other scalar types, which are just pointers to the range in the
18127 -- original tree, this would otherwise be an orphan).
18129 -- The tree is left unanalyzed. When the type is frozen, the processing
18130 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
18131 -- analyzed, and uses this as an indication that it should complete
18132 -- work on the range (it will know the final small and size values).
18134 procedure Set_Fixed_Range
18140 S : constant Node_Id :=
18142 Low_Bound => Make_Real_Literal (Loc, Lo),
18143 High_Bound => Make_Real_Literal (Loc, Hi));
18145 Set_Scalar_Range (E, S);
18147 end Set_Fixed_Range;
18149 ----------------------------------
18150 -- Set_Scalar_Range_For_Subtype --
18151 ----------------------------------
18153 procedure Set_Scalar_Range_For_Subtype
18154 (Def_Id : Entity_Id;
18158 Kind : constant Entity_Kind := Ekind (Def_Id);
18161 Set_Scalar_Range (Def_Id, R);
18163 -- We need to link the range into the tree before resolving it so
18164 -- that types that are referenced, including importantly the subtype
18165 -- itself, are properly frozen (Freeze_Expression requires that the
18166 -- expression be properly linked into the tree). Of course if it is
18167 -- already linked in, then we do not disturb the current link.
18169 if No (Parent (R)) then
18170 Set_Parent (R, Def_Id);
18173 -- Reset the kind of the subtype during analysis of the range, to
18174 -- catch possible premature use in the bounds themselves.
18176 Set_Ekind (Def_Id, E_Void);
18177 Process_Range_Expr_In_Decl (R, Subt);
18178 Set_Ekind (Def_Id, Kind);
18179 end Set_Scalar_Range_For_Subtype;
18181 --------------------------------------------------------
18182 -- Set_Stored_Constraint_From_Discriminant_Constraint --
18183 --------------------------------------------------------
18185 procedure Set_Stored_Constraint_From_Discriminant_Constraint
18189 -- Make sure set if encountered during Expand_To_Stored_Constraint
18191 Set_Stored_Constraint (E, No_Elist);
18193 -- Give it the right value
18195 if Is_Constrained (E) and then Has_Discriminants (E) then
18196 Set_Stored_Constraint (E,
18197 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
18199 end Set_Stored_Constraint_From_Discriminant_Constraint;
18201 -------------------------------------
18202 -- Signed_Integer_Type_Declaration --
18203 -------------------------------------
18205 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
18206 Implicit_Base : Entity_Id;
18207 Base_Typ : Entity_Id;
18210 Errs : Boolean := False;
18214 function Can_Derive_From (E : Entity_Id) return Boolean;
18215 -- Determine whether given bounds allow derivation from specified type
18217 procedure Check_Bound (Expr : Node_Id);
18218 -- Check bound to make sure it is integral and static. If not, post
18219 -- appropriate error message and set Errs flag
18221 ---------------------
18222 -- Can_Derive_From --
18223 ---------------------
18225 -- Note we check both bounds against both end values, to deal with
18226 -- strange types like ones with a range of 0 .. -12341234.
18228 function Can_Derive_From (E : Entity_Id) return Boolean is
18229 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
18230 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
18232 return Lo <= Lo_Val and then Lo_Val <= Hi
18234 Lo <= Hi_Val and then Hi_Val <= Hi;
18235 end Can_Derive_From;
18241 procedure Check_Bound (Expr : Node_Id) is
18243 -- If a range constraint is used as an integer type definition, each
18244 -- bound of the range must be defined by a static expression of some
18245 -- integer type, but the two bounds need not have the same integer
18246 -- type (Negative bounds are allowed.) (RM 3.5.4)
18248 if not Is_Integer_Type (Etype (Expr)) then
18250 ("integer type definition bounds must be of integer type", Expr);
18253 elsif not Is_OK_Static_Expression (Expr) then
18254 Flag_Non_Static_Expr
18255 ("non-static expression used for integer type bound!", Expr);
18258 -- The bounds are folded into literals, and we set their type to be
18259 -- universal, to avoid typing difficulties: we cannot set the type
18260 -- of the literal to the new type, because this would be a forward
18261 -- reference for the back end, and if the original type is user-
18262 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
18265 if Is_Entity_Name (Expr) then
18266 Fold_Uint (Expr, Expr_Value (Expr), True);
18269 Set_Etype (Expr, Universal_Integer);
18273 -- Start of processing for Signed_Integer_Type_Declaration
18276 -- Create an anonymous base type
18279 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
18281 -- Analyze and check the bounds, they can be of any integer type
18283 Lo := Low_Bound (Def);
18284 Hi := High_Bound (Def);
18286 -- Arbitrarily use Integer as the type if either bound had an error
18288 if Hi = Error or else Lo = Error then
18289 Base_Typ := Any_Integer;
18290 Set_Error_Posted (T, True);
18292 -- Here both bounds are OK expressions
18295 Analyze_And_Resolve (Lo, Any_Integer);
18296 Analyze_And_Resolve (Hi, Any_Integer);
18302 Hi := Type_High_Bound (Standard_Long_Long_Integer);
18303 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
18306 -- Find type to derive from
18308 Lo_Val := Expr_Value (Lo);
18309 Hi_Val := Expr_Value (Hi);
18311 if Can_Derive_From (Standard_Short_Short_Integer) then
18312 Base_Typ := Base_Type (Standard_Short_Short_Integer);
18314 elsif Can_Derive_From (Standard_Short_Integer) then
18315 Base_Typ := Base_Type (Standard_Short_Integer);
18317 elsif Can_Derive_From (Standard_Integer) then
18318 Base_Typ := Base_Type (Standard_Integer);
18320 elsif Can_Derive_From (Standard_Long_Integer) then
18321 Base_Typ := Base_Type (Standard_Long_Integer);
18323 elsif Can_Derive_From (Standard_Long_Long_Integer) then
18324 Base_Typ := Base_Type (Standard_Long_Long_Integer);
18327 Base_Typ := Base_Type (Standard_Long_Long_Integer);
18328 Error_Msg_N ("integer type definition bounds out of range", Def);
18329 Hi := Type_High_Bound (Standard_Long_Long_Integer);
18330 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
18334 -- Complete both implicit base and declared first subtype entities
18336 Set_Etype (Implicit_Base, Base_Typ);
18337 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
18338 Set_Size_Info (Implicit_Base, (Base_Typ));
18339 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
18340 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
18342 Set_Ekind (T, E_Signed_Integer_Subtype);
18343 Set_Etype (T, Implicit_Base);
18345 Set_Size_Info (T, (Implicit_Base));
18346 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
18347 Set_Scalar_Range (T, Def);
18348 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
18349 Set_Is_Constrained (T);
18350 end Signed_Integer_Type_Declaration;