1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2015, 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 Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Debug; use Debug;
30 with Elists; use Elists;
31 with Einfo; use Einfo;
32 with Errout; use Errout;
33 with Eval_Fat; use Eval_Fat;
34 with Exp_Ch3; use Exp_Ch3;
35 with Exp_Ch9; use Exp_Ch9;
36 with Exp_Disp; use Exp_Disp;
37 with Exp_Dist; use Exp_Dist;
38 with Exp_Tss; use Exp_Tss;
39 with Exp_Util; use Exp_Util;
40 with Fname; use Fname;
41 with Freeze; use Freeze;
42 with Ghost; use Ghost;
43 with Itypes; use Itypes;
44 with Layout; use Layout;
46 with Lib.Xref; use Lib.Xref;
47 with Namet; use Namet;
48 with Nmake; use Nmake;
50 with Restrict; use Restrict;
51 with Rident; use Rident;
52 with Rtsfind; use Rtsfind;
54 with Sem_Aux; use Sem_Aux;
55 with Sem_Case; use Sem_Case;
56 with Sem_Cat; use Sem_Cat;
57 with Sem_Ch6; use Sem_Ch6;
58 with Sem_Ch7; use Sem_Ch7;
59 with Sem_Ch8; use Sem_Ch8;
60 with Sem_Ch10; use Sem_Ch10;
61 with Sem_Ch13; use Sem_Ch13;
62 with Sem_Dim; use Sem_Dim;
63 with Sem_Disp; use Sem_Disp;
64 with Sem_Dist; use Sem_Dist;
65 with Sem_Elim; use Sem_Elim;
66 with Sem_Eval; use Sem_Eval;
67 with Sem_Mech; use Sem_Mech;
68 with Sem_Prag; use Sem_Prag;
69 with Sem_Res; use Sem_Res;
70 with Sem_Smem; use Sem_Smem;
71 with Sem_Type; use Sem_Type;
72 with Sem_Util; use Sem_Util;
73 with Sem_Warn; use Sem_Warn;
74 with Stand; use Stand;
75 with Sinfo; use Sinfo;
76 with Sinput; use Sinput;
77 with Snames; use Snames;
78 with Targparm; use Targparm;
79 with Tbuild; use Tbuild;
80 with Ttypes; use Ttypes;
81 with Uintp; use Uintp;
82 with Urealp; use Urealp;
84 package body Sem_Ch3 is
86 -----------------------
87 -- Local Subprograms --
88 -----------------------
90 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
91 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
92 -- abstract interface types implemented by a record type or a derived
95 procedure Analyze_Object_Contract (Obj_Id : Entity_Id);
96 -- Analyze all delayed pragmas chained on the contract of object Obj_Id as
97 -- if they appeared at the end of the declarative region. The pragmas to be
105 procedure Build_Derived_Type
107 Parent_Type : Entity_Id;
108 Derived_Type : Entity_Id;
109 Is_Completion : Boolean;
110 Derive_Subps : Boolean := True);
111 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
112 -- the N_Full_Type_Declaration node containing the derived type definition.
113 -- Parent_Type is the entity for the parent type in the derived type
114 -- definition and Derived_Type the actual derived type. Is_Completion must
115 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
116 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
117 -- completion of a private type declaration. If Is_Completion is set to
118 -- True, N is the completion of a private type declaration and Derived_Type
119 -- is different from the defining identifier inside N (i.e. Derived_Type /=
120 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
121 -- subprograms should be derived. The only case where this parameter is
122 -- False is when Build_Derived_Type is recursively called to process an
123 -- implicit derived full type for a type derived from a private type (in
124 -- that case the subprograms must only be derived for the private view of
127 -- ??? These flags need a bit of re-examination and re-documentation:
128 -- ??? are they both necessary (both seem related to the recursion)?
130 procedure Build_Derived_Access_Type
132 Parent_Type : Entity_Id;
133 Derived_Type : Entity_Id);
134 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
135 -- create an implicit base if the parent type is constrained or if the
136 -- subtype indication has a constraint.
138 procedure Build_Derived_Array_Type
140 Parent_Type : Entity_Id;
141 Derived_Type : Entity_Id);
142 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
143 -- create an implicit base if the parent type is constrained or if the
144 -- subtype indication has a constraint.
146 procedure Build_Derived_Concurrent_Type
148 Parent_Type : Entity_Id;
149 Derived_Type : Entity_Id);
150 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
151 -- protected type, inherit entries and protected subprograms, check
152 -- legality of discriminant constraints if any.
154 procedure Build_Derived_Enumeration_Type
156 Parent_Type : Entity_Id;
157 Derived_Type : Entity_Id);
158 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
159 -- type, we must create a new list of literals. Types derived from
160 -- Character and [Wide_]Wide_Character are special-cased.
162 procedure Build_Derived_Numeric_Type
164 Parent_Type : Entity_Id;
165 Derived_Type : Entity_Id);
166 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
167 -- an anonymous base type, and propagate constraint to subtype if needed.
169 procedure Build_Derived_Private_Type
171 Parent_Type : Entity_Id;
172 Derived_Type : Entity_Id;
173 Is_Completion : Boolean;
174 Derive_Subps : Boolean := True);
175 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
176 -- because the parent may or may not have a completion, and the derivation
177 -- may itself be a completion.
179 procedure Build_Derived_Record_Type
181 Parent_Type : Entity_Id;
182 Derived_Type : Entity_Id;
183 Derive_Subps : Boolean := True);
184 -- Subsidiary procedure used for tagged and untagged record types
185 -- by Build_Derived_Type and Analyze_Private_Extension_Declaration.
186 -- All parameters are as in Build_Derived_Type except that N, in
187 -- addition to being an N_Full_Type_Declaration node, can also be an
188 -- N_Private_Extension_Declaration node. See the definition of this routine
189 -- for much more info. Derive_Subps indicates whether subprograms should be
190 -- derived from the parent type. The only case where Derive_Subps is False
191 -- is for an implicit derived full type for a type derived from a private
192 -- type (see Build_Derived_Type).
194 procedure Build_Discriminal (Discrim : Entity_Id);
195 -- Create the discriminal corresponding to discriminant Discrim, that is
196 -- the parameter corresponding to Discrim to be used in initialization
197 -- procedures for the type where Discrim is a discriminant. Discriminals
198 -- are not used during semantic analysis, and are not fully defined
199 -- entities until expansion. Thus they are not given a scope until
200 -- initialization procedures are built.
202 function Build_Discriminant_Constraints
205 Derived_Def : Boolean := False) return Elist_Id;
206 -- Validate discriminant constraints and return the list of the constraints
207 -- in order of discriminant declarations, where T is the discriminated
208 -- unconstrained type. Def is the N_Subtype_Indication node where the
209 -- discriminants constraints for T are specified. Derived_Def is True
210 -- when building the discriminant constraints in a derived type definition
211 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
212 -- type and Def is the constraint "(xxx)" on T and this routine sets the
213 -- Corresponding_Discriminant field of the discriminants in the derived
214 -- type D to point to the corresponding discriminants in the parent type T.
216 procedure Build_Discriminated_Subtype
220 Related_Nod : Node_Id;
221 For_Access : Boolean := False);
222 -- Subsidiary procedure to Constrain_Discriminated_Type and to
223 -- Process_Incomplete_Dependents. Given
225 -- T (a possibly discriminated base type)
226 -- Def_Id (a very partially built subtype for T),
228 -- the call completes Def_Id to be the appropriate E_*_Subtype.
230 -- The Elist is the list of discriminant constraints if any (it is set
231 -- to No_Elist if T is not a discriminated type, and to an empty list if
232 -- T has discriminants but there are no discriminant constraints). The
233 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
234 -- The For_Access says whether or not this subtype is really constraining
235 -- an access type. That is its sole purpose is the designated type of an
236 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
237 -- is built to avoid freezing T when the access subtype is frozen.
239 function Build_Scalar_Bound
242 Der_T : Entity_Id) return Node_Id;
243 -- The bounds of a derived scalar type are conversions of the bounds of
244 -- the parent type. Optimize the representation if the bounds are literals.
245 -- Needs a more complete spec--what are the parameters exactly, and what
246 -- exactly is the returned value, and how is Bound affected???
248 procedure Build_Underlying_Full_View
252 -- If the completion of a private type is itself derived from a private
253 -- type, or if the full view of a private subtype is itself private, the
254 -- back-end has no way to compute the actual size of this type. We build
255 -- an internal subtype declaration of the proper parent type to convey
256 -- this information. This extra mechanism is needed because a full
257 -- view cannot itself have a full view (it would get clobbered during
260 procedure Check_Access_Discriminant_Requires_Limited
263 -- Check the restriction that the type to which an access discriminant
264 -- belongs must be a concurrent type or a descendant of a type with
265 -- the reserved word 'limited' in its declaration.
267 procedure Check_Anonymous_Access_Components
271 Comp_List : Node_Id);
272 -- Ada 2005 AI-382: an access component in a record definition can refer to
273 -- the enclosing record, in which case it denotes the type itself, and not
274 -- the current instance of the type. We create an anonymous access type for
275 -- the component, and flag it as an access to a component, so accessibility
276 -- checks are properly performed on it. The declaration of the access type
277 -- is placed ahead of that of the record to prevent order-of-elaboration
278 -- circularity issues in Gigi. We create an incomplete type for the record
279 -- declaration, which is the designated type of the anonymous access.
281 procedure Check_Delta_Expression (E : Node_Id);
282 -- Check that the expression represented by E is suitable for use as a
283 -- delta expression, i.e. it is of real type and is static.
285 procedure Check_Digits_Expression (E : Node_Id);
286 -- Check that the expression represented by E is suitable for use as a
287 -- digits expression, i.e. it is of integer type, positive and static.
289 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
290 -- Validate the initialization of an object declaration. T is the required
291 -- type, and Exp is the initialization expression.
293 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
294 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
296 procedure Check_Or_Process_Discriminants
299 Prev : Entity_Id := Empty);
300 -- If N is the full declaration of the completion T of an incomplete or
301 -- private type, check its discriminants (which are already known to be
302 -- conformant with those of the partial view, see Find_Type_Name),
303 -- otherwise process them. Prev is the entity of the partial declaration,
306 procedure Check_Real_Bound (Bound : Node_Id);
307 -- Check given bound for being of real type and static. If not, post an
308 -- appropriate message, and rewrite the bound with the real literal zero.
310 procedure Constant_Redeclaration
314 -- Various checks on legality of full declaration of deferred constant.
315 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
316 -- node. The caller has not yet set any attributes of this entity.
318 function Contain_Interface
320 Ifaces : Elist_Id) return Boolean;
321 -- Ada 2005: Determine whether Iface is present in the list Ifaces
323 procedure Convert_Scalar_Bounds
325 Parent_Type : Entity_Id;
326 Derived_Type : Entity_Id;
328 -- For derived scalar types, convert the bounds in the type definition to
329 -- the derived type, and complete their analysis. Given a constraint of the
330 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
331 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
332 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
333 -- subtype are conversions of those bounds to the derived_type, so that
334 -- their typing is consistent.
336 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
337 -- Copies attributes from array base type T2 to array base type T1. Copies
338 -- only attributes that apply to base types, but not subtypes.
340 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
341 -- Copies attributes from array subtype T2 to array subtype T1. Copies
342 -- attributes that apply to both subtypes and base types.
344 procedure Create_Constrained_Components
348 Constraints : Elist_Id);
349 -- Build the list of entities for a constrained discriminated record
350 -- subtype. If a component depends on a discriminant, replace its subtype
351 -- using the discriminant values in the discriminant constraint. Subt
352 -- is the defining identifier for the subtype whose list of constrained
353 -- entities we will create. Decl_Node is the type declaration node where
354 -- we will attach all the itypes created. Typ is the base discriminated
355 -- type for the subtype Subt. Constraints is the list of discriminant
356 -- constraints for Typ.
358 function Constrain_Component_Type
360 Constrained_Typ : Entity_Id;
361 Related_Node : Node_Id;
363 Constraints : Elist_Id) return Entity_Id;
364 -- Given a discriminated base type Typ, a list of discriminant constraints,
365 -- Constraints, for Typ and a component Comp of Typ, create and return the
366 -- type corresponding to Etype (Comp) where all discriminant references
367 -- are replaced with the corresponding constraint. If Etype (Comp) contains
368 -- no discriminant references then it is returned as-is. Constrained_Typ
369 -- is the final constrained subtype to which the constrained component
370 -- belongs. Related_Node is the node where we attach all created itypes.
372 procedure Constrain_Access
373 (Def_Id : in out Entity_Id;
375 Related_Nod : Node_Id);
376 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
377 -- an anonymous type created for a subtype indication. In that case it is
378 -- created in the procedure and attached to Related_Nod.
380 procedure Constrain_Array
381 (Def_Id : in out Entity_Id;
383 Related_Nod : Node_Id;
384 Related_Id : Entity_Id;
386 -- Apply a list of index constraints to an unconstrained array type. The
387 -- first parameter is the entity for the resulting subtype. A value of
388 -- Empty for Def_Id indicates that an implicit type must be created, but
389 -- creation is delayed (and must be done by this procedure) because other
390 -- subsidiary implicit types must be created first (which is why Def_Id
391 -- is an in/out parameter). The second parameter is a subtype indication
392 -- node for the constrained array to be created (e.g. something of the
393 -- form string (1 .. 10)). Related_Nod gives the place where this type
394 -- has to be inserted in the tree. The Related_Id and Suffix parameters
395 -- are used to build the associated Implicit type name.
397 procedure Constrain_Concurrent
398 (Def_Id : in out Entity_Id;
400 Related_Nod : Node_Id;
401 Related_Id : Entity_Id;
403 -- Apply list of discriminant constraints to an unconstrained concurrent
406 -- SI is the N_Subtype_Indication node containing the constraint and
407 -- the unconstrained type to constrain.
409 -- Def_Id is the entity for the resulting constrained subtype. A value
410 -- of Empty for Def_Id indicates that an implicit type must be created,
411 -- but creation is delayed (and must be done by this procedure) because
412 -- other subsidiary implicit types must be created first (which is why
413 -- Def_Id is an in/out parameter).
415 -- Related_Nod gives the place where this type has to be inserted
418 -- The last two arguments are used to create its external name if needed.
420 function Constrain_Corresponding_Record
421 (Prot_Subt : Entity_Id;
422 Corr_Rec : Entity_Id;
423 Related_Nod : Node_Id) return Entity_Id;
424 -- When constraining a protected type or task type with discriminants,
425 -- constrain the corresponding record with the same discriminant values.
427 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
428 -- Constrain a decimal fixed point type with a digits constraint and/or a
429 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
431 procedure Constrain_Discriminated_Type
434 Related_Nod : Node_Id;
435 For_Access : Boolean := False);
436 -- Process discriminant constraints of composite type. Verify that values
437 -- have been provided for all discriminants, that the original type is
438 -- unconstrained, and that the types of the supplied expressions match
439 -- the discriminant types. The first three parameters are like in routine
440 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
443 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
444 -- Constrain an enumeration type with a range constraint. This is identical
445 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
447 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
448 -- Constrain a floating point type with either a digits constraint
449 -- and/or a range constraint, building a E_Floating_Point_Subtype.
451 procedure Constrain_Index
454 Related_Nod : Node_Id;
455 Related_Id : Entity_Id;
458 -- Process an index constraint S in a constrained array declaration. The
459 -- constraint can be a subtype name, or a range with or without an explicit
460 -- subtype mark. The index is the corresponding index of the unconstrained
461 -- array. The Related_Id and Suffix parameters are used to build the
462 -- associated Implicit type name.
464 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
465 -- Build subtype of a signed or modular integer type
467 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
468 -- Constrain an ordinary fixed point type with a range constraint, and
469 -- build an E_Ordinary_Fixed_Point_Subtype entity.
471 procedure Copy_And_Swap (Priv, Full : Entity_Id);
472 -- Copy the Priv entity into the entity of its full declaration then swap
473 -- the two entities in such a manner that the former private type is now
474 -- seen as a full type.
476 procedure Decimal_Fixed_Point_Type_Declaration
479 -- Create a new decimal fixed point type, and apply the constraint to
480 -- obtain a subtype of this new type.
482 procedure Complete_Private_Subtype
485 Full_Base : Entity_Id;
486 Related_Nod : Node_Id);
487 -- Complete the implicit full view of a private subtype by setting the
488 -- appropriate semantic fields. If the full view of the parent is a record
489 -- type, build constrained components of subtype.
491 procedure Derive_Progenitor_Subprograms
492 (Parent_Type : Entity_Id;
493 Tagged_Type : Entity_Id);
494 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
495 -- operations of progenitors of Tagged_Type, and replace the subsidiary
496 -- subtypes with Tagged_Type, to build the specs of the inherited interface
497 -- primitives. The derived primitives are aliased to those of the
498 -- interface. This routine takes care also of transferring to the full view
499 -- subprograms associated with the partial view of Tagged_Type that cover
500 -- interface primitives.
502 procedure Derived_Standard_Character
504 Parent_Type : Entity_Id;
505 Derived_Type : Entity_Id);
506 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
507 -- derivations from types Standard.Character and Standard.Wide_Character.
509 procedure Derived_Type_Declaration
512 Is_Completion : Boolean);
513 -- Process a derived type declaration. Build_Derived_Type is invoked
514 -- to process the actual derived type definition. Parameters N and
515 -- Is_Completion have the same meaning as in Build_Derived_Type.
516 -- T is the N_Defining_Identifier for the entity defined in the
517 -- N_Full_Type_Declaration node N, that is T is the derived type.
519 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
520 -- Insert each literal in symbol table, as an overloadable identifier. Each
521 -- enumeration type is mapped into a sequence of integers, and each literal
522 -- is defined as a constant with integer value. If any of the literals are
523 -- character literals, the type is a character type, which means that
524 -- strings are legal aggregates for arrays of components of the type.
526 function Expand_To_Stored_Constraint
528 Constraint : Elist_Id) return Elist_Id;
529 -- Given a constraint (i.e. a list of expressions) on the discriminants of
530 -- Typ, expand it into a constraint on the stored discriminants and return
531 -- the new list of expressions constraining the stored discriminants.
533 function Find_Type_Of_Object
535 Related_Nod : Node_Id) return Entity_Id;
536 -- Get type entity for object referenced by Obj_Def, attaching the implicit
537 -- types generated to Related_Nod.
539 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
540 -- Create a new float and apply the constraint to obtain subtype of it
542 function Has_Range_Constraint (N : Node_Id) return Boolean;
543 -- Given an N_Subtype_Indication node N, return True if a range constraint
544 -- is present, either directly, or as part of a digits or delta constraint.
545 -- In addition, a digits constraint in the decimal case returns True, since
546 -- it establishes a default range if no explicit range is present.
548 function Inherit_Components
550 Parent_Base : Entity_Id;
551 Derived_Base : Entity_Id;
553 Inherit_Discr : Boolean;
554 Discs : Elist_Id) return Elist_Id;
555 -- Called from Build_Derived_Record_Type to inherit the components of
556 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
557 -- For more information on derived types and component inheritance please
558 -- consult the comment above the body of Build_Derived_Record_Type.
560 -- N is the original derived type declaration
562 -- Is_Tagged is set if we are dealing with tagged types
564 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
565 -- Parent_Base, otherwise no discriminants are inherited.
567 -- Discs gives the list of constraints that apply to Parent_Base in the
568 -- derived type declaration. If Discs is set to No_Elist, then we have
569 -- the following situation:
571 -- type Parent (D1..Dn : ..) is [tagged] record ...;
572 -- type Derived is new Parent [with ...];
574 -- which gets treated as
576 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
578 -- For untagged types the returned value is an association list. The list
579 -- starts from the association (Parent_Base => Derived_Base), and then it
580 -- contains a sequence of the associations of the form
582 -- (Old_Component => New_Component),
584 -- where Old_Component is the Entity_Id of a component in Parent_Base and
585 -- New_Component is the Entity_Id of the corresponding component in
586 -- Derived_Base. For untagged records, this association list is needed when
587 -- copying the record declaration for the derived base. In the tagged case
588 -- the value returned is irrelevant.
590 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id);
591 -- Propagate static and dynamic predicate flags from a parent to the
592 -- subtype in a subtype declaration with and without constraints.
594 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean;
595 -- Subsidiary to Check_Abstract_Overriding and Derive_Subprogram.
596 -- Determine whether subprogram Subp is a procedure subject to pragma
597 -- Extensions_Visible with value False and has at least one controlling
598 -- parameter of mode OUT.
600 function Is_Valid_Constraint_Kind
602 Constraint_Kind : Node_Kind) return Boolean;
603 -- Returns True if it is legal to apply the given kind of constraint to the
604 -- given kind of type (index constraint to an array type, for example).
606 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
607 -- Create new modular type. Verify that modulus is in bounds
609 procedure New_Concatenation_Op (Typ : Entity_Id);
610 -- Create an abbreviated declaration for an operator in order to
611 -- materialize concatenation on array types.
613 procedure Ordinary_Fixed_Point_Type_Declaration
616 -- Create a new ordinary fixed point type, and apply the constraint to
617 -- obtain subtype of it.
619 procedure Prepare_Private_Subtype_Completion
621 Related_Nod : Node_Id);
622 -- Id is a subtype of some private type. Creates the full declaration
623 -- associated with Id whenever possible, i.e. when the full declaration
624 -- of the base type is already known. Records each subtype into
625 -- Private_Dependents of the base type.
627 procedure Process_Incomplete_Dependents
631 -- Process all entities that depend on an incomplete type. There include
632 -- subtypes, subprogram types that mention the incomplete type in their
633 -- profiles, and subprogram with access parameters that designate the
636 -- Inc_T is the defining identifier of an incomplete type declaration, its
637 -- Ekind is E_Incomplete_Type.
639 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
641 -- Full_T is N's defining identifier.
643 -- Subtypes of incomplete types with discriminants are completed when the
644 -- parent type is. This is simpler than private subtypes, because they can
645 -- only appear in the same scope, and there is no need to exchange views.
646 -- Similarly, access_to_subprogram types may have a parameter or a return
647 -- type that is an incomplete type, and that must be replaced with the
650 -- If the full type is tagged, subprogram with access parameters that
651 -- designated the incomplete may be primitive operations of the full type,
652 -- and have to be processed accordingly.
654 procedure Process_Real_Range_Specification (Def : Node_Id);
655 -- Given the type definition for a real type, this procedure processes and
656 -- checks the real range specification of this type definition if one is
657 -- present. If errors are found, error messages are posted, and the
658 -- Real_Range_Specification of Def is reset to Empty.
660 procedure Propagate_Default_Init_Cond_Attributes
661 (From_Typ : Entity_Id;
663 Parent_To_Derivation : Boolean := False;
664 Private_To_Full_View : Boolean := False);
665 -- Subsidiary to routines Build_Derived_Type and Process_Full_View. Inherit
666 -- all attributes related to pragma Default_Initial_Condition from From_Typ
667 -- to To_Typ. Flag Parent_To_Derivation should be set when the context is
668 -- the creation of a derived type. Flag Private_To_Full_View should be set
669 -- when processing both views of a private type.
671 procedure Record_Type_Declaration
675 -- Process a record type declaration (for both untagged and tagged
676 -- records). Parameters T and N are exactly like in procedure
677 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
678 -- for this routine. If this is the completion of an incomplete type
679 -- declaration, Prev is the entity of the incomplete declaration, used for
680 -- cross-referencing. Otherwise Prev = T.
682 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
683 -- This routine is used to process the actual record type definition (both
684 -- for untagged and tagged records). Def is a record type definition node.
685 -- This procedure analyzes the components in this record type definition.
686 -- Prev_T is the entity for the enclosing record type. It is provided so
687 -- that its Has_Task flag can be set if any of the component have Has_Task
688 -- set. If the declaration is the completion of an incomplete type
689 -- declaration, Prev_T is the original incomplete type, whose full view is
692 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
693 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
694 -- build a copy of the declaration tree of the parent, and we create
695 -- independently the list of components for the derived type. Semantic
696 -- information uses the component entities, but record representation
697 -- clauses are validated on the declaration tree. This procedure replaces
698 -- discriminants and components in the declaration with those that have
699 -- been created by Inherit_Components.
701 procedure Set_Fixed_Range
706 -- Build a range node with the given bounds and set it as the Scalar_Range
707 -- of the given fixed-point type entity. Loc is the source location used
708 -- for the constructed range. See body for further details.
710 procedure Set_Scalar_Range_For_Subtype
714 -- This routine is used to set the scalar range field for a subtype given
715 -- Def_Id, the entity for the subtype, and R, the range expression for the
716 -- scalar range. Subt provides the parent subtype to be used to analyze,
717 -- resolve, and check the given range.
719 procedure Set_Default_SSO (T : Entity_Id);
720 -- T is the entity for an array or record being declared. This procedure
721 -- sets the flags SSO_Set_Low_By_Default/SSO_Set_High_By_Default according
722 -- to the setting of Opt.Default_SSO.
724 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
725 -- Create a new signed integer entity, and apply the constraint to obtain
726 -- the required first named subtype of this type.
728 procedure Set_Stored_Constraint_From_Discriminant_Constraint
730 -- E is some record type. This routine computes E's Stored_Constraint
731 -- from its Discriminant_Constraint.
733 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
734 -- Check that an entity in a list of progenitors is an interface,
735 -- emit error otherwise.
737 -----------------------
738 -- Access_Definition --
739 -----------------------
741 function Access_Definition
742 (Related_Nod : Node_Id;
743 N : Node_Id) return Entity_Id
745 Anon_Type : Entity_Id;
746 Anon_Scope : Entity_Id;
747 Desig_Type : Entity_Id;
748 Enclosing_Prot_Type : Entity_Id := Empty;
751 Check_SPARK_05_Restriction ("access type is not allowed", N);
753 if Is_Entry (Current_Scope)
754 and then Is_Task_Type (Etype (Scope (Current_Scope)))
756 Error_Msg_N ("task entries cannot have access parameters", N);
760 -- Ada 2005: For an object declaration the corresponding anonymous
761 -- type is declared in the current scope.
763 -- If the access definition is the return type of another access to
764 -- function, scope is the current one, because it is the one of the
765 -- current type declaration, except for the pathological case below.
767 if Nkind_In (Related_Nod, N_Object_Declaration,
768 N_Access_Function_Definition)
770 Anon_Scope := Current_Scope;
772 -- A pathological case: function returning access functions that
773 -- return access functions, etc. Each anonymous access type created
774 -- is in the enclosing scope of the outermost function.
781 while Nkind_In (Par, N_Access_Function_Definition,
787 if Nkind (Par) = N_Function_Specification then
788 Anon_Scope := Scope (Defining_Entity (Par));
792 -- For the anonymous function result case, retrieve the scope of the
793 -- function specification's associated entity rather than using the
794 -- current scope. The current scope will be the function itself if the
795 -- formal part is currently being analyzed, but will be the parent scope
796 -- in the case of a parameterless function, and we always want to use
797 -- the function's parent scope. Finally, if the function is a child
798 -- unit, we must traverse the tree to retrieve the proper entity.
800 elsif Nkind (Related_Nod) = N_Function_Specification
801 and then Nkind (Parent (N)) /= N_Parameter_Specification
803 -- If the current scope is a protected type, the anonymous access
804 -- is associated with one of the protected operations, and must
805 -- be available in the scope that encloses the protected declaration.
806 -- Otherwise the type is in the scope enclosing the subprogram.
808 -- If the function has formals, The return type of a subprogram
809 -- declaration is analyzed in the scope of the subprogram (see
810 -- Process_Formals) and thus the protected type, if present, is
811 -- the scope of the current function scope.
813 if Ekind (Current_Scope) = E_Protected_Type then
814 Enclosing_Prot_Type := Current_Scope;
816 elsif Ekind (Current_Scope) = E_Function
817 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
819 Enclosing_Prot_Type := Scope (Current_Scope);
822 if Present (Enclosing_Prot_Type) then
823 Anon_Scope := Scope (Enclosing_Prot_Type);
826 Anon_Scope := Scope (Defining_Entity (Related_Nod));
829 -- For an access type definition, if the current scope is a child
830 -- unit it is the scope of the type.
832 elsif Is_Compilation_Unit (Current_Scope) then
833 Anon_Scope := Current_Scope;
835 -- For access formals, access components, and access discriminants, the
836 -- scope is that of the enclosing declaration,
839 Anon_Scope := Scope (Current_Scope);
844 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
847 and then Ada_Version >= Ada_2005
849 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
852 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
853 -- the corresponding semantic routine
855 if Present (Access_To_Subprogram_Definition (N)) then
857 -- Compiler runtime units are compiled in Ada 2005 mode when building
858 -- the runtime library but must also be compilable in Ada 95 mode
859 -- (when bootstrapping the compiler).
861 Check_Compiler_Unit ("anonymous access to subprogram", N);
863 Access_Subprogram_Declaration
864 (T_Name => Anon_Type,
865 T_Def => Access_To_Subprogram_Definition (N));
867 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
869 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
871 Set_Ekind (Anon_Type, E_Anonymous_Access_Subprogram_Type);
874 Set_Can_Use_Internal_Rep
875 (Anon_Type, not Always_Compatible_Rep_On_Target);
877 -- If the anonymous access is associated with a protected operation,
878 -- create a reference to it after the enclosing protected definition
879 -- because the itype will be used in the subsequent bodies.
881 -- If the anonymous access itself is protected, a full type
882 -- declaratiton will be created for it, so that the equivalent
883 -- record type can be constructed. For further details, see
884 -- Replace_Anonymous_Access_To_Protected-Subprogram.
886 if Ekind (Current_Scope) = E_Protected_Type
887 and then not Protected_Present (Access_To_Subprogram_Definition (N))
889 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
895 Find_Type (Subtype_Mark (N));
896 Desig_Type := Entity (Subtype_Mark (N));
898 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
899 Set_Etype (Anon_Type, Anon_Type);
901 -- Make sure the anonymous access type has size and alignment fields
902 -- set, as required by gigi. This is necessary in the case of the
903 -- Task_Body_Procedure.
905 if not Has_Private_Component (Desig_Type) then
906 Layout_Type (Anon_Type);
909 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
910 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
911 -- the null value is allowed. In Ada 95 the null value is never allowed.
913 if Ada_Version >= Ada_2005 then
914 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
916 Set_Can_Never_Be_Null (Anon_Type, True);
919 -- The anonymous access type is as public as the discriminated type or
920 -- subprogram that defines it. It is imported (for back-end purposes)
921 -- if the designated type is.
923 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
925 -- Ada 2005 (AI-231): Propagate the access-constant attribute
927 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
929 -- The context is either a subprogram declaration, object declaration,
930 -- or an access discriminant, in a private or a full type declaration.
931 -- In the case of a subprogram, if the designated type is incomplete,
932 -- the operation will be a primitive operation of the full type, to be
933 -- updated subsequently. If the type is imported through a limited_with
934 -- clause, the subprogram is not a primitive operation of the type
935 -- (which is declared elsewhere in some other scope).
937 if Ekind (Desig_Type) = E_Incomplete_Type
938 and then not From_Limited_With (Desig_Type)
939 and then Is_Overloadable (Current_Scope)
941 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
942 Set_Has_Delayed_Freeze (Current_Scope);
945 -- Ada 2005: If the designated type is an interface that may contain
946 -- tasks, create a Master entity for the declaration. This must be done
947 -- before expansion of the full declaration, because the declaration may
948 -- include an expression that is an allocator, whose expansion needs the
949 -- proper Master for the created tasks.
951 if Nkind (Related_Nod) = N_Object_Declaration and then Expander_Active
953 if Is_Interface (Desig_Type) and then Is_Limited_Record (Desig_Type)
955 Build_Class_Wide_Master (Anon_Type);
957 -- Similarly, if the type is an anonymous access that designates
958 -- tasks, create a master entity for it in the current context.
960 elsif Has_Task (Desig_Type) and then Comes_From_Source (Related_Nod)
962 Build_Master_Entity (Defining_Identifier (Related_Nod));
963 Build_Master_Renaming (Anon_Type);
967 -- For a private component of a protected type, it is imperative that
968 -- the back-end elaborate the type immediately after the protected
969 -- declaration, because this type will be used in the declarations
970 -- created for the component within each protected body, so we must
971 -- create an itype reference for it now.
973 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
974 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
976 -- Similarly, if the access definition is the return result of a
977 -- function, create an itype reference for it because it will be used
978 -- within the function body. For a regular function that is not a
979 -- compilation unit, insert reference after the declaration. For a
980 -- protected operation, insert it after the enclosing protected type
981 -- declaration. In either case, do not create a reference for a type
982 -- obtained through a limited_with clause, because this would introduce
983 -- semantic dependencies.
985 -- Similarly, do not create a reference if the designated type is a
986 -- generic formal, because no use of it will reach the backend.
988 elsif Nkind (Related_Nod) = N_Function_Specification
989 and then not From_Limited_With (Desig_Type)
990 and then not Is_Generic_Type (Desig_Type)
992 if Present (Enclosing_Prot_Type) then
993 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
995 elsif Is_List_Member (Parent (Related_Nod))
996 and then Nkind (Parent (N)) /= N_Parameter_Specification
998 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
1001 -- Finally, create an itype reference for an object declaration of an
1002 -- anonymous access type. This is strictly necessary only for deferred
1003 -- constants, but in any case will avoid out-of-scope problems in the
1006 elsif Nkind (Related_Nod) = N_Object_Declaration then
1007 Build_Itype_Reference (Anon_Type, Related_Nod);
1011 end Access_Definition;
1013 -----------------------------------
1014 -- Access_Subprogram_Declaration --
1015 -----------------------------------
1017 procedure Access_Subprogram_Declaration
1018 (T_Name : Entity_Id;
1021 procedure Check_For_Premature_Usage (Def : Node_Id);
1022 -- Check that type T_Name is not used, directly or recursively, as a
1023 -- parameter or a return type in Def. Def is either a subtype, an
1024 -- access_definition, or an access_to_subprogram_definition.
1026 -------------------------------
1027 -- Check_For_Premature_Usage --
1028 -------------------------------
1030 procedure Check_For_Premature_Usage (Def : Node_Id) is
1034 -- Check for a subtype mark
1036 if Nkind (Def) in N_Has_Etype then
1037 if Etype (Def) = T_Name then
1039 ("type& cannot be used before end of its declaration", Def);
1042 -- If this is not a subtype, then this is an access_definition
1044 elsif Nkind (Def) = N_Access_Definition then
1045 if Present (Access_To_Subprogram_Definition (Def)) then
1046 Check_For_Premature_Usage
1047 (Access_To_Subprogram_Definition (Def));
1049 Check_For_Premature_Usage (Subtype_Mark (Def));
1052 -- The only cases left are N_Access_Function_Definition and
1053 -- N_Access_Procedure_Definition.
1056 if Present (Parameter_Specifications (Def)) then
1057 Param := First (Parameter_Specifications (Def));
1058 while Present (Param) loop
1059 Check_For_Premature_Usage (Parameter_Type (Param));
1060 Param := Next (Param);
1064 if Nkind (Def) = N_Access_Function_Definition then
1065 Check_For_Premature_Usage (Result_Definition (Def));
1068 end Check_For_Premature_Usage;
1072 Formals : constant List_Id := Parameter_Specifications (T_Def);
1075 Desig_Type : constant Entity_Id :=
1076 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1078 -- Start of processing for Access_Subprogram_Declaration
1081 Check_SPARK_05_Restriction ("access type is not allowed", T_Def);
1083 -- Associate the Itype node with the inner full-type declaration or
1084 -- subprogram spec or entry body. This is required to handle nested
1085 -- anonymous declarations. For example:
1088 -- (X : access procedure
1089 -- (Y : access procedure
1092 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1093 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1094 N_Private_Type_Declaration,
1095 N_Private_Extension_Declaration,
1096 N_Procedure_Specification,
1097 N_Function_Specification,
1101 Nkind_In (D_Ityp, N_Object_Declaration,
1102 N_Object_Renaming_Declaration,
1103 N_Formal_Object_Declaration,
1104 N_Formal_Type_Declaration,
1105 N_Task_Type_Declaration,
1106 N_Protected_Type_Declaration))
1108 D_Ityp := Parent (D_Ityp);
1109 pragma Assert (D_Ityp /= Empty);
1112 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1114 if Nkind_In (D_Ityp, N_Procedure_Specification,
1115 N_Function_Specification)
1117 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1119 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1120 N_Object_Declaration,
1121 N_Object_Renaming_Declaration,
1122 N_Formal_Type_Declaration)
1124 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1127 if Nkind (T_Def) = N_Access_Function_Definition then
1128 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1130 Acc : constant Node_Id := Result_Definition (T_Def);
1133 if Present (Access_To_Subprogram_Definition (Acc))
1135 Protected_Present (Access_To_Subprogram_Definition (Acc))
1139 Replace_Anonymous_Access_To_Protected_Subprogram
1145 Access_Definition (T_Def, Result_Definition (T_Def)));
1150 Analyze (Result_Definition (T_Def));
1153 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1156 -- If a null exclusion is imposed on the result type, then
1157 -- create a null-excluding itype (an access subtype) and use
1158 -- it as the function's Etype.
1160 if Is_Access_Type (Typ)
1161 and then Null_Exclusion_In_Return_Present (T_Def)
1163 Set_Etype (Desig_Type,
1164 Create_Null_Excluding_Itype
1166 Related_Nod => T_Def,
1167 Scope_Id => Current_Scope));
1170 if From_Limited_With (Typ) then
1172 -- AI05-151: Incomplete types are allowed in all basic
1173 -- declarations, including access to subprograms.
1175 if Ada_Version >= Ada_2012 then
1180 ("illegal use of incomplete type&",
1181 Result_Definition (T_Def), Typ);
1184 elsif Ekind (Current_Scope) = E_Package
1185 and then In_Private_Part (Current_Scope)
1187 if Ekind (Typ) = E_Incomplete_Type then
1188 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1190 elsif Is_Class_Wide_Type (Typ)
1191 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1194 (Desig_Type, Private_Dependents (Etype (Typ)));
1198 Set_Etype (Desig_Type, Typ);
1203 if not (Is_Type (Etype (Desig_Type))) then
1205 ("expect type in function specification",
1206 Result_Definition (T_Def));
1210 Set_Etype (Desig_Type, Standard_Void_Type);
1213 if Present (Formals) then
1214 Push_Scope (Desig_Type);
1216 -- Some special tests here. These special tests can be removed
1217 -- if and when Itypes always have proper parent pointers to their
1220 -- Special test 1) Link defining_identifier of formals. Required by
1221 -- First_Formal to provide its functionality.
1227 F := First (Formals);
1229 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1230 -- when it is part of an unconstrained type and subtype expansion
1231 -- is disabled. To avoid back-end problems with shared profiles,
1232 -- use previous subprogram type as the designated type, and then
1233 -- remove scope added above.
1235 if ASIS_Mode and then Present (Scope (Defining_Identifier (F)))
1237 Set_Etype (T_Name, T_Name);
1238 Init_Size_Align (T_Name);
1239 Set_Directly_Designated_Type (T_Name,
1240 Scope (Defining_Identifier (F)));
1245 while Present (F) loop
1246 if No (Parent (Defining_Identifier (F))) then
1247 Set_Parent (Defining_Identifier (F), F);
1254 Process_Formals (Formals, Parent (T_Def));
1256 -- Special test 2) End_Scope requires that the parent pointer be set
1257 -- to something reasonable, but Itypes don't have parent pointers. So
1258 -- we set it and then unset it ???
1260 Set_Parent (Desig_Type, T_Name);
1262 Set_Parent (Desig_Type, Empty);
1265 -- Check for premature usage of the type being defined
1267 Check_For_Premature_Usage (T_Def);
1269 -- The return type and/or any parameter type may be incomplete. Mark the
1270 -- subprogram_type as depending on the incomplete type, so that it can
1271 -- be updated when the full type declaration is seen. This only applies
1272 -- to incomplete types declared in some enclosing scope, not to limited
1273 -- views from other packages.
1275 -- Prior to Ada 2012, access to functions can only have in_parameters.
1277 if Present (Formals) then
1278 Formal := First_Formal (Desig_Type);
1279 while Present (Formal) loop
1280 if Ekind (Formal) /= E_In_Parameter
1281 and then Nkind (T_Def) = N_Access_Function_Definition
1282 and then Ada_Version < Ada_2012
1284 Error_Msg_N ("functions can only have IN parameters", Formal);
1287 if Ekind (Etype (Formal)) = E_Incomplete_Type
1288 and then In_Open_Scopes (Scope (Etype (Formal)))
1290 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1291 Set_Has_Delayed_Freeze (Desig_Type);
1294 Next_Formal (Formal);
1298 -- Check whether an indirect call without actuals may be possible. This
1299 -- is used when resolving calls whose result is then indexed.
1301 May_Need_Actuals (Desig_Type);
1303 -- If the return type is incomplete, this is legal as long as the type
1304 -- is declared in the current scope and will be completed in it (rather
1305 -- than being part of limited view).
1307 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1308 and then not Has_Delayed_Freeze (Desig_Type)
1309 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1311 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1312 Set_Has_Delayed_Freeze (Desig_Type);
1315 Check_Delayed_Subprogram (Desig_Type);
1317 if Protected_Present (T_Def) then
1318 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1319 Set_Convention (Desig_Type, Convention_Protected);
1321 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1324 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1326 Set_Etype (T_Name, T_Name);
1327 Init_Size_Align (T_Name);
1328 Set_Directly_Designated_Type (T_Name, Desig_Type);
1330 Generate_Reference_To_Formals (T_Name);
1332 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1334 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1336 Check_Restriction (No_Access_Subprograms, T_Def);
1337 end Access_Subprogram_Declaration;
1339 ----------------------------
1340 -- Access_Type_Declaration --
1341 ----------------------------
1343 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1344 P : constant Node_Id := Parent (Def);
1345 S : constant Node_Id := Subtype_Indication (Def);
1347 Full_Desig : Entity_Id;
1350 Check_SPARK_05_Restriction ("access type is not allowed", Def);
1352 -- Check for permissible use of incomplete type
1354 if Nkind (S) /= N_Subtype_Indication then
1357 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1358 Set_Directly_Designated_Type (T, Entity (S));
1360 -- If the designated type is a limited view, we cannot tell if
1361 -- the full view contains tasks, and there is no way to handle
1362 -- that full view in a client. We create a master entity for the
1363 -- scope, which will be used when a client determines that one
1366 if From_Limited_With (Entity (S))
1367 and then not Is_Class_Wide_Type (Entity (S))
1369 Set_Ekind (T, E_Access_Type);
1370 Build_Master_Entity (T);
1371 Build_Master_Renaming (T);
1375 Set_Directly_Designated_Type (T, Process_Subtype (S, P, T, 'P'));
1378 -- If the access definition is of the form: ACCESS NOT NULL ..
1379 -- the subtype indication must be of an access type. Create
1380 -- a null-excluding subtype of it.
1382 if Null_Excluding_Subtype (Def) then
1383 if not Is_Access_Type (Entity (S)) then
1384 Error_Msg_N ("null exclusion must apply to access type", Def);
1388 Loc : constant Source_Ptr := Sloc (S);
1390 Nam : constant Entity_Id := Make_Temporary (Loc, 'S');
1394 Make_Subtype_Declaration (Loc,
1395 Defining_Identifier => Nam,
1396 Subtype_Indication =>
1397 New_Occurrence_Of (Entity (S), Loc));
1398 Set_Null_Exclusion_Present (Decl);
1399 Insert_Before (Parent (Def), Decl);
1401 Set_Entity (S, Nam);
1407 Set_Directly_Designated_Type (T,
1408 Process_Subtype (S, P, T, 'P'));
1411 if All_Present (Def) or Constant_Present (Def) then
1412 Set_Ekind (T, E_General_Access_Type);
1414 Set_Ekind (T, E_Access_Type);
1417 Full_Desig := Designated_Type (T);
1419 if Base_Type (Full_Desig) = T then
1420 Error_Msg_N ("access type cannot designate itself", S);
1422 -- In Ada 2005, the type may have a limited view through some unit in
1423 -- its own context, allowing the following circularity that cannot be
1424 -- detected earlier.
1426 elsif Is_Class_Wide_Type (Full_Desig) and then Etype (Full_Desig) = T
1429 ("access type cannot designate its own classwide type", S);
1431 -- Clean up indication of tagged status to prevent cascaded errors
1433 Set_Is_Tagged_Type (T, False);
1438 -- If the type has appeared already in a with_type clause, it is frozen
1439 -- and the pointer size is already set. Else, initialize.
1441 if not From_Limited_With (T) then
1442 Init_Size_Align (T);
1445 -- Note that Has_Task is always false, since the access type itself
1446 -- is not a task type. See Einfo for more description on this point.
1447 -- Exactly the same consideration applies to Has_Controlled_Component
1448 -- and to Has_Protected.
1450 Set_Has_Task (T, False);
1451 Set_Has_Controlled_Component (T, False);
1452 Set_Has_Protected (T, False);
1454 -- Initialize field Finalization_Master explicitly to Empty, to avoid
1455 -- problems where an incomplete view of this entity has been previously
1456 -- established by a limited with and an overlaid version of this field
1457 -- (Stored_Constraint) was initialized for the incomplete view.
1459 -- This reset is performed in most cases except where the access type
1460 -- has been created for the purposes of allocating or deallocating a
1461 -- build-in-place object. Such access types have explicitly set pools
1462 -- and finalization masters.
1464 if No (Associated_Storage_Pool (T)) then
1465 Set_Finalization_Master (T, Empty);
1468 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1471 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1472 Set_Is_Access_Constant (T, Constant_Present (Def));
1473 end Access_Type_Declaration;
1475 ----------------------------------
1476 -- Add_Interface_Tag_Components --
1477 ----------------------------------
1479 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1480 Loc : constant Source_Ptr := Sloc (N);
1484 procedure Add_Tag (Iface : Entity_Id);
1485 -- Add tag for one of the progenitor interfaces
1491 procedure Add_Tag (Iface : Entity_Id) is
1498 pragma Assert (Is_Tagged_Type (Iface) and then Is_Interface (Iface));
1500 -- This is a reasonable place to propagate predicates
1502 if Has_Predicates (Iface) then
1503 Set_Has_Predicates (Typ);
1507 Make_Component_Definition (Loc,
1508 Aliased_Present => True,
1509 Subtype_Indication =>
1510 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1512 Tag := Make_Temporary (Loc, 'V');
1515 Make_Component_Declaration (Loc,
1516 Defining_Identifier => Tag,
1517 Component_Definition => Def);
1519 Analyze_Component_Declaration (Decl);
1521 Set_Analyzed (Decl);
1522 Set_Ekind (Tag, E_Component);
1524 Set_Is_Aliased (Tag);
1525 Set_Related_Type (Tag, Iface);
1526 Init_Component_Location (Tag);
1528 pragma Assert (Is_Frozen (Iface));
1530 Set_DT_Entry_Count (Tag,
1531 DT_Entry_Count (First_Entity (Iface)));
1533 if No (Last_Tag) then
1536 Insert_After (Last_Tag, Decl);
1541 -- If the ancestor has discriminants we need to give special support
1542 -- to store the offset_to_top value of the secondary dispatch tables.
1543 -- For this purpose we add a supplementary component just after the
1544 -- field that contains the tag associated with each secondary DT.
1546 if Typ /= Etype (Typ) and then Has_Discriminants (Etype (Typ)) then
1548 Make_Component_Definition (Loc,
1549 Subtype_Indication =>
1550 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1552 Offset := Make_Temporary (Loc, 'V');
1555 Make_Component_Declaration (Loc,
1556 Defining_Identifier => Offset,
1557 Component_Definition => Def);
1559 Analyze_Component_Declaration (Decl);
1561 Set_Analyzed (Decl);
1562 Set_Ekind (Offset, E_Component);
1563 Set_Is_Aliased (Offset);
1564 Set_Related_Type (Offset, Iface);
1565 Init_Component_Location (Offset);
1566 Insert_After (Last_Tag, Decl);
1577 -- Start of processing for Add_Interface_Tag_Components
1580 if not RTE_Available (RE_Interface_Tag) then
1582 ("(Ada 2005) interface types not supported by this run-time!",
1587 if Ekind (Typ) /= E_Record_Type
1588 or else (Is_Concurrent_Record_Type (Typ)
1589 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1590 or else (not Is_Concurrent_Record_Type (Typ)
1591 and then No (Interfaces (Typ))
1592 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1597 -- Find the current last tag
1599 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1600 Ext := Record_Extension_Part (Type_Definition (N));
1602 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1603 Ext := Type_Definition (N);
1608 if not (Present (Component_List (Ext))) then
1609 Set_Null_Present (Ext, False);
1611 Set_Component_List (Ext,
1612 Make_Component_List (Loc,
1613 Component_Items => L,
1614 Null_Present => False));
1616 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1617 L := Component_Items
1619 (Record_Extension_Part
1620 (Type_Definition (N))));
1622 L := Component_Items
1624 (Type_Definition (N)));
1627 -- Find the last tag component
1630 while Present (Comp) loop
1631 if Nkind (Comp) = N_Component_Declaration
1632 and then Is_Tag (Defining_Identifier (Comp))
1641 -- At this point L references the list of components and Last_Tag
1642 -- references the current last tag (if any). Now we add the tag
1643 -- corresponding with all the interfaces that are not implemented
1646 if Present (Interfaces (Typ)) then
1647 Elmt := First_Elmt (Interfaces (Typ));
1648 while Present (Elmt) loop
1649 Add_Tag (Node (Elmt));
1653 end Add_Interface_Tag_Components;
1655 -------------------------------------
1656 -- Add_Internal_Interface_Entities --
1657 -------------------------------------
1659 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1662 Iface_Elmt : Elmt_Id;
1663 Iface_Prim : Entity_Id;
1664 Ifaces_List : Elist_Id;
1665 New_Subp : Entity_Id := Empty;
1667 Restore_Scope : Boolean := False;
1670 pragma Assert (Ada_Version >= Ada_2005
1671 and then Is_Record_Type (Tagged_Type)
1672 and then Is_Tagged_Type (Tagged_Type)
1673 and then Has_Interfaces (Tagged_Type)
1674 and then not Is_Interface (Tagged_Type));
1676 -- Ensure that the internal entities are added to the scope of the type
1678 if Scope (Tagged_Type) /= Current_Scope then
1679 Push_Scope (Scope (Tagged_Type));
1680 Restore_Scope := True;
1683 Collect_Interfaces (Tagged_Type, Ifaces_List);
1685 Iface_Elmt := First_Elmt (Ifaces_List);
1686 while Present (Iface_Elmt) loop
1687 Iface := Node (Iface_Elmt);
1689 -- Originally we excluded here from this processing interfaces that
1690 -- are parents of Tagged_Type because their primitives are located
1691 -- in the primary dispatch table (and hence no auxiliary internal
1692 -- entities are required to handle secondary dispatch tables in such
1693 -- case). However, these auxiliary entities are also required to
1694 -- handle derivations of interfaces in formals of generics (see
1695 -- Derive_Subprograms).
1697 Elmt := First_Elmt (Primitive_Operations (Iface));
1698 while Present (Elmt) loop
1699 Iface_Prim := Node (Elmt);
1701 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1703 Find_Primitive_Covering_Interface
1704 (Tagged_Type => Tagged_Type,
1705 Iface_Prim => Iface_Prim);
1707 if No (Prim) and then Serious_Errors_Detected > 0 then
1711 pragma Assert (Present (Prim));
1713 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1714 -- differs from the name of the interface primitive then it is
1715 -- a private primitive inherited from a parent type. In such
1716 -- case, given that Tagged_Type covers the interface, the
1717 -- inherited private primitive becomes visible. For such
1718 -- purpose we add a new entity that renames the inherited
1719 -- private primitive.
1721 if Chars (Prim) /= Chars (Iface_Prim) then
1722 pragma Assert (Has_Suffix (Prim, 'P'));
1724 (New_Subp => New_Subp,
1725 Parent_Subp => Iface_Prim,
1726 Derived_Type => Tagged_Type,
1727 Parent_Type => Iface);
1728 Set_Alias (New_Subp, Prim);
1729 Set_Is_Abstract_Subprogram
1730 (New_Subp, Is_Abstract_Subprogram (Prim));
1734 (New_Subp => New_Subp,
1735 Parent_Subp => Iface_Prim,
1736 Derived_Type => Tagged_Type,
1737 Parent_Type => Iface);
1739 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1740 -- associated with interface types. These entities are
1741 -- only registered in the list of primitives of its
1742 -- corresponding tagged type because they are only used
1743 -- to fill the contents of the secondary dispatch tables.
1744 -- Therefore they are removed from the homonym chains.
1746 Set_Is_Hidden (New_Subp);
1747 Set_Is_Internal (New_Subp);
1748 Set_Alias (New_Subp, Prim);
1749 Set_Is_Abstract_Subprogram
1750 (New_Subp, Is_Abstract_Subprogram (Prim));
1751 Set_Interface_Alias (New_Subp, Iface_Prim);
1753 -- If the returned type is an interface then propagate it to
1754 -- the returned type. Needed by the thunk to generate the code
1755 -- which displaces "this" to reference the corresponding
1756 -- secondary dispatch table in the returned object.
1758 if Is_Interface (Etype (Iface_Prim)) then
1759 Set_Etype (New_Subp, Etype (Iface_Prim));
1762 -- Internal entities associated with interface types are
1763 -- only registered in the list of primitives of the tagged
1764 -- type. They are only used to fill the contents of the
1765 -- secondary dispatch tables. Therefore they are not needed
1766 -- in the homonym chains.
1768 Remove_Homonym (New_Subp);
1770 -- Hidden entities associated with interfaces must have set
1771 -- the Has_Delay_Freeze attribute to ensure that, in case of
1772 -- locally defined tagged types (or compiling with static
1773 -- dispatch tables generation disabled) the corresponding
1774 -- entry of the secondary dispatch table is filled when
1775 -- such an entity is frozen.
1777 Set_Has_Delayed_Freeze (New_Subp);
1784 Next_Elmt (Iface_Elmt);
1787 if Restore_Scope then
1790 end Add_Internal_Interface_Entities;
1792 -----------------------------------
1793 -- Analyze_Component_Declaration --
1794 -----------------------------------
1796 procedure Analyze_Component_Declaration (N : Node_Id) is
1797 Loc : constant Source_Ptr := Sloc (N);
1798 Id : constant Entity_Id := Defining_Identifier (N);
1799 E : constant Node_Id := Expression (N);
1800 Typ : constant Node_Id :=
1801 Subtype_Indication (Component_Definition (N));
1805 function Contains_POC (Constr : Node_Id) return Boolean;
1806 -- Determines whether a constraint uses the discriminant of a record
1807 -- type thus becoming a per-object constraint (POC).
1809 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1810 -- Typ is the type of the current component, check whether this type is
1811 -- a limited type. Used to validate declaration against that of
1812 -- enclosing record.
1818 function Contains_POC (Constr : Node_Id) return Boolean is
1820 -- Prevent cascaded errors
1822 if Error_Posted (Constr) then
1826 case Nkind (Constr) is
1827 when N_Attribute_Reference =>
1828 return Attribute_Name (Constr) = Name_Access
1829 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1831 when N_Discriminant_Association =>
1832 return Denotes_Discriminant (Expression (Constr));
1834 when N_Identifier =>
1835 return Denotes_Discriminant (Constr);
1837 when N_Index_Or_Discriminant_Constraint =>
1842 IDC := First (Constraints (Constr));
1843 while Present (IDC) loop
1845 -- One per-object constraint is sufficient
1847 if Contains_POC (IDC) then
1858 return Denotes_Discriminant (Low_Bound (Constr))
1860 Denotes_Discriminant (High_Bound (Constr));
1862 when N_Range_Constraint =>
1863 return Denotes_Discriminant (Range_Expression (Constr));
1871 ----------------------
1872 -- Is_Known_Limited --
1873 ----------------------
1875 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1876 P : constant Entity_Id := Etype (Typ);
1877 R : constant Entity_Id := Root_Type (Typ);
1880 if Is_Limited_Record (Typ) then
1883 -- If the root type is limited (and not a limited interface)
1884 -- so is the current type
1886 elsif Is_Limited_Record (R)
1887 and then (not Is_Interface (R) or else not Is_Limited_Interface (R))
1891 -- Else the type may have a limited interface progenitor, but a
1892 -- limited record parent.
1894 elsif R /= P and then Is_Limited_Record (P) then
1900 end Is_Known_Limited;
1902 -- Start of processing for Analyze_Component_Declaration
1905 Generate_Definition (Id);
1908 if Present (Typ) then
1909 T := Find_Type_Of_Object
1910 (Subtype_Indication (Component_Definition (N)), N);
1912 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1913 Check_SPARK_05_Restriction ("subtype mark required", Typ);
1916 -- Ada 2005 (AI-230): Access Definition case
1919 pragma Assert (Present
1920 (Access_Definition (Component_Definition (N))));
1922 T := Access_Definition
1924 N => Access_Definition (Component_Definition (N)));
1925 Set_Is_Local_Anonymous_Access (T);
1927 -- Ada 2005 (AI-254)
1929 if Present (Access_To_Subprogram_Definition
1930 (Access_Definition (Component_Definition (N))))
1931 and then Protected_Present (Access_To_Subprogram_Definition
1933 (Component_Definition (N))))
1935 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1939 -- If the subtype is a constrained subtype of the enclosing record,
1940 -- (which must have a partial view) the back-end does not properly
1941 -- handle the recursion. Rewrite the component declaration with an
1942 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1943 -- the tree directly because side effects have already been removed from
1944 -- discriminant constraints.
1946 if Ekind (T) = E_Access_Subtype
1947 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1948 and then Comes_From_Source (T)
1949 and then Nkind (Parent (T)) = N_Subtype_Declaration
1950 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1953 (Subtype_Indication (Component_Definition (N)),
1954 New_Copy_Tree (Subtype_Indication (Parent (T))));
1955 T := Find_Type_Of_Object
1956 (Subtype_Indication (Component_Definition (N)), N);
1959 -- If the component declaration includes a default expression, then we
1960 -- check that the component is not of a limited type (RM 3.7(5)),
1961 -- and do the special preanalysis of the expression (see section on
1962 -- "Handling of Default and Per-Object Expressions" in the spec of
1966 Check_SPARK_05_Restriction ("default expression is not allowed", E);
1967 Preanalyze_Default_Expression (E, T);
1968 Check_Initialization (T, E);
1970 if Ada_Version >= Ada_2005
1971 and then Ekind (T) = E_Anonymous_Access_Type
1972 and then Etype (E) /= Any_Type
1974 -- Check RM 3.9.2(9): "if the expected type for an expression is
1975 -- an anonymous access-to-specific tagged type, then the object
1976 -- designated by the expression shall not be dynamically tagged
1977 -- unless it is a controlling operand in a call on a dispatching
1980 if Is_Tagged_Type (Directly_Designated_Type (T))
1982 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1984 Ekind (Directly_Designated_Type (Etype (E))) =
1988 ("access to specific tagged type required (RM 3.9.2(9))", E);
1991 -- (Ada 2005: AI-230): Accessibility check for anonymous
1994 if Type_Access_Level (Etype (E)) >
1995 Deepest_Type_Access_Level (T)
1998 ("expression has deeper access level than component " &
1999 "(RM 3.10.2 (12.2))", E);
2002 -- The initialization expression is a reference to an access
2003 -- discriminant. The type of the discriminant is always deeper
2004 -- than any access type.
2006 if Ekind (Etype (E)) = E_Anonymous_Access_Type
2007 and then Is_Entity_Name (E)
2008 and then Ekind (Entity (E)) = E_In_Parameter
2009 and then Present (Discriminal_Link (Entity (E)))
2012 ("discriminant has deeper accessibility level than target",
2018 -- The parent type may be a private view with unknown discriminants,
2019 -- and thus unconstrained. Regular components must be constrained.
2021 if Is_Indefinite_Subtype (T) and then Chars (Id) /= Name_uParent then
2022 if Is_Class_Wide_Type (T) then
2024 ("class-wide subtype with unknown discriminants" &
2025 " in component declaration",
2026 Subtype_Indication (Component_Definition (N)));
2029 ("unconstrained subtype in component declaration",
2030 Subtype_Indication (Component_Definition (N)));
2033 -- Components cannot be abstract, except for the special case of
2034 -- the _Parent field (case of extending an abstract tagged type)
2036 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
2037 Error_Msg_N ("type of a component cannot be abstract", N);
2041 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
2043 -- The component declaration may have a per-object constraint, set
2044 -- the appropriate flag in the defining identifier of the subtype.
2046 if Present (Subtype_Indication (Component_Definition (N))) then
2048 Sindic : constant Node_Id :=
2049 Subtype_Indication (Component_Definition (N));
2051 if Nkind (Sindic) = N_Subtype_Indication
2052 and then Present (Constraint (Sindic))
2053 and then Contains_POC (Constraint (Sindic))
2055 Set_Has_Per_Object_Constraint (Id);
2060 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2061 -- out some static checks.
2063 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
2064 Null_Exclusion_Static_Checks (N);
2067 -- If this component is private (or depends on a private type), flag the
2068 -- record type to indicate that some operations are not available.
2070 P := Private_Component (T);
2074 -- Check for circular definitions
2076 if P = Any_Type then
2077 Set_Etype (Id, Any_Type);
2079 -- There is a gap in the visibility of operations only if the
2080 -- component type is not defined in the scope of the record type.
2082 elsif Scope (P) = Scope (Current_Scope) then
2085 elsif Is_Limited_Type (P) then
2086 Set_Is_Limited_Composite (Current_Scope);
2089 Set_Is_Private_Composite (Current_Scope);
2094 and then Is_Limited_Type (T)
2095 and then Chars (Id) /= Name_uParent
2096 and then Is_Tagged_Type (Current_Scope)
2098 if Is_Derived_Type (Current_Scope)
2099 and then not Is_Known_Limited (Current_Scope)
2102 ("extension of nonlimited type cannot have limited components",
2105 if Is_Interface (Root_Type (Current_Scope)) then
2107 ("\limitedness is not inherited from limited interface", N);
2108 Error_Msg_N ("\add LIMITED to type indication", N);
2111 Explain_Limited_Type (T, N);
2112 Set_Etype (Id, Any_Type);
2113 Set_Is_Limited_Composite (Current_Scope, False);
2115 elsif not Is_Derived_Type (Current_Scope)
2116 and then not Is_Limited_Record (Current_Scope)
2117 and then not Is_Concurrent_Type (Current_Scope)
2120 ("nonlimited tagged type cannot have limited components", N);
2121 Explain_Limited_Type (T, N);
2122 Set_Etype (Id, Any_Type);
2123 Set_Is_Limited_Composite (Current_Scope, False);
2127 -- If the component is an unconstrained task or protected type with
2128 -- discriminants, the component and the enclosing record are limited
2129 -- and the component is constrained by its default values. Compute
2130 -- its actual subtype, else it may be allocated the maximum size by
2131 -- the backend, and possibly overflow.
2133 if Is_Concurrent_Type (T)
2134 and then not Is_Constrained (T)
2135 and then Has_Discriminants (T)
2136 and then not Has_Discriminants (Current_Scope)
2139 Act_T : constant Entity_Id := Build_Default_Subtype (T, N);
2141 Set_Etype (Id, Act_T);
2142 Set_Component_Definition (N,
2143 Make_Component_Definition (Loc,
2144 Subtype_Indication => New_Occurrence_Of (Act_T, Loc)));
2148 Set_Original_Record_Component (Id, Id);
2150 if Has_Aspects (N) then
2151 Analyze_Aspect_Specifications (N, Id);
2154 Analyze_Dimension (N);
2155 end Analyze_Component_Declaration;
2157 --------------------------
2158 -- Analyze_Declarations --
2159 --------------------------
2161 procedure Analyze_Declarations (L : List_Id) is
2164 procedure Adjust_Decl;
2165 -- Adjust Decl not to include implicit label declarations, since these
2166 -- have strange Sloc values that result in elaboration check problems.
2167 -- (They have the sloc of the label as found in the source, and that
2168 -- is ahead of the current declarative part).
2170 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id);
2171 -- Determine whether Body_Decl denotes the body of a late controlled
2172 -- primitive (either Initialize, Adjust or Finalize). If this is the
2173 -- case, add a proper spec if the body lacks one. The spec is inserted
2174 -- before Body_Decl and immedately analyzed.
2176 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id);
2177 -- Spec_Id is the entity of a package that may define abstract states.
2178 -- If the states have visible refinement, remove the visibility of each
2179 -- constituent at the end of the package body declarations.
2185 procedure Adjust_Decl is
2187 while Present (Prev (Decl))
2188 and then Nkind (Decl) = N_Implicit_Label_Declaration
2194 --------------------------------------
2195 -- Handle_Late_Controlled_Primitive --
2196 --------------------------------------
2198 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id) is
2199 Body_Spec : constant Node_Id := Specification (Body_Decl);
2200 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2201 Loc : constant Source_Ptr := Sloc (Body_Id);
2202 Params : constant List_Id :=
2203 Parameter_Specifications (Body_Spec);
2205 Spec_Id : Entity_Id;
2209 -- Consider only procedure bodies whose name matches one of the three
2210 -- controlled primitives.
2212 if Nkind (Body_Spec) /= N_Procedure_Specification
2213 or else not Nam_In (Chars (Body_Id), Name_Adjust,
2219 -- A controlled primitive must have exactly one formal which is not
2220 -- an anonymous access type.
2222 elsif List_Length (Params) /= 1 then
2226 Typ := Parameter_Type (First (Params));
2228 if Nkind (Typ) = N_Access_Definition then
2234 -- The type of the formal must be derived from [Limited_]Controlled
2236 if not Is_Controlled (Entity (Typ)) then
2240 -- Check whether a specification exists for this body. We do not
2241 -- analyze the spec of the body in full, because it will be analyzed
2242 -- again when the body is properly analyzed, and we cannot create
2243 -- duplicate entries in the formals chain. We look for an explicit
2244 -- specification because the body may be an overriding operation and
2245 -- an inherited spec may be present.
2247 Spec_Id := Current_Entity (Body_Id);
2249 while Present (Spec_Id) loop
2250 if Ekind_In (Spec_Id, E_Procedure, E_Generic_Procedure)
2251 and then Scope (Spec_Id) = Current_Scope
2252 and then Present (First_Formal (Spec_Id))
2253 and then No (Next_Formal (First_Formal (Spec_Id)))
2254 and then Etype (First_Formal (Spec_Id)) = Entity (Typ)
2255 and then Comes_From_Source (Spec_Id)
2260 Spec_Id := Homonym (Spec_Id);
2263 -- At this point the body is known to be a late controlled primitive.
2264 -- Generate a matching spec and insert it before the body. Note the
2265 -- use of Copy_Separate_Tree - we want an entirely separate semantic
2266 -- tree in this case.
2268 Spec := Copy_Separate_Tree (Body_Spec);
2270 -- Ensure that the subprogram declaration does not inherit the null
2271 -- indicator from the body as we now have a proper spec/body pair.
2273 Set_Null_Present (Spec, False);
2275 Insert_Before_And_Analyze (Body_Decl,
2276 Make_Subprogram_Declaration (Loc, Specification => Spec));
2277 end Handle_Late_Controlled_Primitive;
2279 --------------------------------
2280 -- Remove_Visible_Refinements --
2281 --------------------------------
2283 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id) is
2284 State_Elmt : Elmt_Id;
2286 if Present (Abstract_States (Spec_Id)) then
2287 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2288 while Present (State_Elmt) loop
2289 Set_Has_Visible_Refinement (Node (State_Elmt), False);
2290 Next_Elmt (State_Elmt);
2293 end Remove_Visible_Refinements;
2298 Freeze_From : Entity_Id := Empty;
2299 Next_Decl : Node_Id;
2300 Spec_Id : Entity_Id;
2302 Body_Seen : Boolean := False;
2303 -- Flag set when the first body [stub] is encountered
2305 In_Package_Body : Boolean := False;
2306 -- Flag set when the current declaration list belongs to a package body
2308 -- Start of processing for Analyze_Declarations
2311 if Restriction_Check_Required (SPARK_05) then
2312 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2316 while Present (Decl) loop
2318 -- Package spec cannot contain a package declaration in SPARK
2320 if Nkind (Decl) = N_Package_Declaration
2321 and then Nkind (Parent (L)) = N_Package_Specification
2323 Check_SPARK_05_Restriction
2324 ("package specification cannot contain a package declaration",
2328 -- Complete analysis of declaration
2331 Next_Decl := Next (Decl);
2333 if No (Freeze_From) then
2334 Freeze_From := First_Entity (Current_Scope);
2337 -- At the end of a declarative part, freeze remaining entities
2338 -- declared in it. The end of the visible declarations of package
2339 -- specification is not the end of a declarative part if private
2340 -- declarations are present. The end of a package declaration is a
2341 -- freezing point only if it a library package. A task definition or
2342 -- protected type definition is not a freeze point either. Finally,
2343 -- we do not freeze entities in generic scopes, because there is no
2344 -- code generated for them and freeze nodes will be generated for
2347 -- The end of a package instantiation is not a freeze point, but
2348 -- for now we make it one, because the generic body is inserted
2349 -- (currently) immediately after. Generic instantiations will not
2350 -- be a freeze point once delayed freezing of bodies is implemented.
2351 -- (This is needed in any case for early instantiations ???).
2353 if No (Next_Decl) then
2354 if Nkind_In (Parent (L), N_Component_List,
2356 N_Protected_Definition)
2360 elsif Nkind (Parent (L)) /= N_Package_Specification then
2361 if Nkind (Parent (L)) = N_Package_Body then
2362 Freeze_From := First_Entity (Current_Scope);
2365 -- There may have been several freezing points previously,
2366 -- for example object declarations or subprogram bodies, but
2367 -- at the end of a declarative part we check freezing from
2368 -- the beginning, even though entities may already be frozen,
2369 -- in order to perform visibility checks on delayed aspects.
2372 Freeze_All (First_Entity (Current_Scope), Decl);
2373 Freeze_From := Last_Entity (Current_Scope);
2375 elsif Scope (Current_Scope) /= Standard_Standard
2376 and then not Is_Child_Unit (Current_Scope)
2377 and then No (Generic_Parent (Parent (L)))
2381 elsif L /= Visible_Declarations (Parent (L))
2382 or else No (Private_Declarations (Parent (L)))
2383 or else Is_Empty_List (Private_Declarations (Parent (L)))
2386 Freeze_All (First_Entity (Current_Scope), Decl);
2387 Freeze_From := Last_Entity (Current_Scope);
2390 -- If next node is a body then freeze all types before the body.
2391 -- An exception occurs for some expander-generated bodies. If these
2392 -- are generated at places where in general language rules would not
2393 -- allow a freeze point, then we assume that the expander has
2394 -- explicitly checked that all required types are properly frozen,
2395 -- and we do not cause general freezing here. This special circuit
2396 -- is used when the encountered body is marked as having already
2399 -- In all other cases (bodies that come from source, and expander
2400 -- generated bodies that have not been analyzed yet), freeze all
2401 -- types now. Note that in the latter case, the expander must take
2402 -- care to attach the bodies at a proper place in the tree so as to
2403 -- not cause unwanted freezing at that point.
2405 elsif not Analyzed (Next_Decl) and then Is_Body (Next_Decl) then
2407 -- When a controlled type is frozen, the expander generates stream
2408 -- and controlled type support routines. If the freeze is caused
2409 -- by the stand alone body of Initialize, Adjust and Finalize, the
2410 -- expander will end up using the wrong version of these routines
2411 -- as the body has not been processed yet. To remedy this, detect
2412 -- a late controlled primitive and create a proper spec for it.
2413 -- This ensures that the primitive will override its inherited
2414 -- counterpart before the freeze takes place.
2416 -- If the declaration we just processed is a body, do not attempt
2417 -- to examine Next_Decl as the late primitive idiom can only apply
2418 -- to the first encountered body.
2420 -- The spec of the late primitive is not generated in ASIS mode to
2421 -- ensure a consistent list of primitives that indicates the true
2422 -- semantic structure of the program (which is not relevant when
2423 -- generating executable code.
2425 -- ??? a cleaner approach may be possible and/or this solution
2426 -- could be extended to general-purpose late primitives, TBD.
2428 if not ASIS_Mode and then not Body_Seen and then not Is_Body (Decl)
2432 if Nkind (Next_Decl) = N_Subprogram_Body then
2433 Handle_Late_Controlled_Primitive (Next_Decl);
2438 Freeze_All (Freeze_From, Decl);
2439 Freeze_From := Last_Entity (Current_Scope);
2445 -- Analyze the contracts of packages and their bodies
2448 Context := Parent (L);
2450 if Nkind (Context) = N_Package_Specification then
2452 -- When a package has private declarations, its contract must be
2453 -- analyzed at the end of the said declarations. This way both the
2454 -- analysis and freeze actions are properly synchronized in case
2455 -- of private type use within the contract.
2457 if L = Private_Declarations (Context) then
2458 Analyze_Package_Contract (Defining_Entity (Context));
2460 -- Build the bodies of the default initial condition procedures
2461 -- for all types subject to pragma Default_Initial_Condition.
2462 -- From a purely Ada stand point, this is a freezing activity,
2463 -- however freezing is not available under GNATprove_Mode. To
2464 -- accomodate both scenarios, the bodies are build at the end
2465 -- of private declaration analysis.
2467 Build_Default_Init_Cond_Procedure_Bodies (L);
2469 -- Otherwise the contract is analyzed at the end of the visible
2472 elsif L = Visible_Declarations (Context)
2473 and then No (Private_Declarations (Context))
2475 Analyze_Package_Contract (Defining_Entity (Context));
2478 elsif Nkind (Context) = N_Package_Body then
2479 In_Package_Body := True;
2480 Spec_Id := Corresponding_Spec (Context);
2482 Analyze_Package_Body_Contract (Defining_Entity (Context));
2486 -- Analyze the contracts of subprogram declarations, subprogram bodies
2487 -- and variables now due to the delayed visibility requirements of their
2491 while Present (Decl) loop
2492 if Nkind (Decl) = N_Object_Declaration then
2493 Analyze_Object_Contract (Defining_Entity (Decl));
2495 elsif Nkind_In (Decl, N_Abstract_Subprogram_Declaration,
2496 N_Generic_Subprogram_Declaration,
2497 N_Subprogram_Declaration)
2499 Analyze_Subprogram_Contract (Defining_Entity (Decl));
2501 elsif Nkind (Decl) = N_Subprogram_Body then
2502 Analyze_Subprogram_Body_Contract (Defining_Entity (Decl));
2504 elsif Nkind (Decl) = N_Subprogram_Body_Stub then
2505 Analyze_Subprogram_Body_Stub_Contract (Defining_Entity (Decl));
2511 -- State refinements are visible upto the end the of the package body
2512 -- declarations. Hide the refinements from visibility to restore the
2513 -- original state conditions.
2515 if In_Package_Body then
2516 Remove_Visible_Refinements (Spec_Id);
2518 end Analyze_Declarations;
2520 -----------------------------------
2521 -- Analyze_Full_Type_Declaration --
2522 -----------------------------------
2524 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2525 Def : constant Node_Id := Type_Definition (N);
2526 Def_Id : constant Entity_Id := Defining_Identifier (N);
2530 Is_Remote : constant Boolean :=
2531 (Is_Remote_Types (Current_Scope)
2532 or else Is_Remote_Call_Interface (Current_Scope))
2533 and then not (In_Private_Part (Current_Scope)
2534 or else In_Package_Body (Current_Scope));
2536 procedure Check_Ops_From_Incomplete_Type;
2537 -- If there is a tagged incomplete partial view of the type, traverse
2538 -- the primitives of the incomplete view and change the type of any
2539 -- controlling formals and result to indicate the full view. The
2540 -- primitives will be added to the full type's primitive operations
2541 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2542 -- is called from Process_Incomplete_Dependents).
2544 ------------------------------------
2545 -- Check_Ops_From_Incomplete_Type --
2546 ------------------------------------
2548 procedure Check_Ops_From_Incomplete_Type is
2555 and then Ekind (Prev) = E_Incomplete_Type
2556 and then Is_Tagged_Type (Prev)
2557 and then Is_Tagged_Type (T)
2559 Elmt := First_Elmt (Primitive_Operations (Prev));
2560 while Present (Elmt) loop
2563 Formal := First_Formal (Op);
2564 while Present (Formal) loop
2565 if Etype (Formal) = Prev then
2566 Set_Etype (Formal, T);
2569 Next_Formal (Formal);
2572 if Etype (Op) = Prev then
2579 end Check_Ops_From_Incomplete_Type;
2581 -- Start of processing for Analyze_Full_Type_Declaration
2584 Prev := Find_Type_Name (N);
2586 -- The type declaration may be subject to pragma Ghost with policy
2587 -- Ignore. Set the mode now to ensure that any nodes generated during
2588 -- analysis and expansion are properly flagged as ignored Ghost.
2590 Set_Ghost_Mode (N, Prev);
2592 -- The full view, if present, now points to the current type. If there
2593 -- is an incomplete partial view, set a link to it, to simplify the
2594 -- retrieval of primitive operations of the type.
2596 -- Ada 2005 (AI-50217): If the type was previously decorated when
2597 -- imported through a LIMITED WITH clause, it appears as incomplete
2598 -- but has no full view.
2600 if Ekind (Prev) = E_Incomplete_Type
2601 and then Present (Full_View (Prev))
2603 T := Full_View (Prev);
2604 Set_Incomplete_View (N, Parent (Prev));
2609 Set_Is_Pure (T, Is_Pure (Current_Scope));
2611 -- We set the flag Is_First_Subtype here. It is needed to set the
2612 -- corresponding flag for the Implicit class-wide-type created
2613 -- during tagged types processing.
2615 Set_Is_First_Subtype (T, True);
2617 -- Only composite types other than array types are allowed to have
2622 -- For derived types, the rule will be checked once we've figured
2623 -- out the parent type.
2625 when N_Derived_Type_Definition =>
2628 -- For record types, discriminants are allowed, unless we are in
2631 when N_Record_Definition =>
2632 if Present (Discriminant_Specifications (N)) then
2633 Check_SPARK_05_Restriction
2634 ("discriminant type is not allowed",
2636 (First (Discriminant_Specifications (N))));
2640 if Present (Discriminant_Specifications (N)) then
2642 ("elementary or array type cannot have discriminants",
2644 (First (Discriminant_Specifications (N))));
2648 -- Elaborate the type definition according to kind, and generate
2649 -- subsidiary (implicit) subtypes where needed. We skip this if it was
2650 -- already done (this happens during the reanalysis that follows a call
2651 -- to the high level optimizer).
2653 if not Analyzed (T) then
2657 when N_Access_To_Subprogram_Definition =>
2658 Access_Subprogram_Declaration (T, Def);
2660 -- If this is a remote access to subprogram, we must create the
2661 -- equivalent fat pointer type, and related subprograms.
2664 Process_Remote_AST_Declaration (N);
2667 -- Validate categorization rule against access type declaration
2668 -- usually a violation in Pure unit, Shared_Passive unit.
2670 Validate_Access_Type_Declaration (T, N);
2672 when N_Access_To_Object_Definition =>
2673 Access_Type_Declaration (T, Def);
2675 -- Validate categorization rule against access type declaration
2676 -- usually a violation in Pure unit, Shared_Passive unit.
2678 Validate_Access_Type_Declaration (T, N);
2680 -- If we are in a Remote_Call_Interface package and define a
2681 -- RACW, then calling stubs and specific stream attributes
2685 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
2687 Add_RACW_Features (Def_Id);
2690 when N_Array_Type_Definition =>
2691 Array_Type_Declaration (T, Def);
2693 when N_Derived_Type_Definition =>
2694 Derived_Type_Declaration (T, N, T /= Def_Id);
2696 when N_Enumeration_Type_Definition =>
2697 Enumeration_Type_Declaration (T, Def);
2699 when N_Floating_Point_Definition =>
2700 Floating_Point_Type_Declaration (T, Def);
2702 when N_Decimal_Fixed_Point_Definition =>
2703 Decimal_Fixed_Point_Type_Declaration (T, Def);
2705 when N_Ordinary_Fixed_Point_Definition =>
2706 Ordinary_Fixed_Point_Type_Declaration (T, Def);
2708 when N_Signed_Integer_Type_Definition =>
2709 Signed_Integer_Type_Declaration (T, Def);
2711 when N_Modular_Type_Definition =>
2712 Modular_Type_Declaration (T, Def);
2714 when N_Record_Definition =>
2715 Record_Type_Declaration (T, N, Prev);
2717 -- If declaration has a parse error, nothing to elaborate.
2723 raise Program_Error;
2728 if Etype (T) = Any_Type then
2732 -- Controlled type is not allowed in SPARK
2734 if Is_Visibly_Controlled (T) then
2735 Check_SPARK_05_Restriction ("controlled type is not allowed", N);
2738 -- A type declared within a Ghost region is automatically Ghost
2739 -- (SPARK RM 6.9(2)).
2741 if Comes_From_Source (T) and then Ghost_Mode > None then
2742 Set_Is_Ghost_Entity (T);
2745 -- Some common processing for all types
2747 Set_Depends_On_Private (T, Has_Private_Component (T));
2748 Check_Ops_From_Incomplete_Type;
2750 -- Both the declared entity, and its anonymous base type if one was
2751 -- created, need freeze nodes allocated.
2754 B : constant Entity_Id := Base_Type (T);
2757 -- In the case where the base type differs from the first subtype, we
2758 -- pre-allocate a freeze node, and set the proper link to the first
2759 -- subtype. Freeze_Entity will use this preallocated freeze node when
2760 -- it freezes the entity.
2762 -- This does not apply if the base type is a generic type, whose
2763 -- declaration is independent of the current derived definition.
2765 if B /= T and then not Is_Generic_Type (B) then
2766 Ensure_Freeze_Node (B);
2767 Set_First_Subtype_Link (Freeze_Node (B), T);
2770 -- A type that is imported through a limited_with clause cannot
2771 -- generate any code, and thus need not be frozen. However, an access
2772 -- type with an imported designated type needs a finalization list,
2773 -- which may be referenced in some other package that has non-limited
2774 -- visibility on the designated type. Thus we must create the
2775 -- finalization list at the point the access type is frozen, to
2776 -- prevent unsatisfied references at link time.
2778 if not From_Limited_With (T) or else Is_Access_Type (T) then
2779 Set_Has_Delayed_Freeze (T);
2783 -- Case where T is the full declaration of some private type which has
2784 -- been swapped in Defining_Identifier (N).
2786 if T /= Def_Id and then Is_Private_Type (Def_Id) then
2787 Process_Full_View (N, T, Def_Id);
2789 -- Record the reference. The form of this is a little strange, since
2790 -- the full declaration has been swapped in. So the first parameter
2791 -- here represents the entity to which a reference is made which is
2792 -- the "real" entity, i.e. the one swapped in, and the second
2793 -- parameter provides the reference location.
2795 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
2796 -- since we don't want a complaint about the full type being an
2797 -- unwanted reference to the private type
2800 B : constant Boolean := Has_Pragma_Unreferenced (T);
2802 Set_Has_Pragma_Unreferenced (T, False);
2803 Generate_Reference (T, T, 'c');
2804 Set_Has_Pragma_Unreferenced (T, B);
2807 Set_Completion_Referenced (Def_Id);
2809 -- For completion of incomplete type, process incomplete dependents
2810 -- and always mark the full type as referenced (it is the incomplete
2811 -- type that we get for any real reference).
2813 elsif Ekind (Prev) = E_Incomplete_Type then
2814 Process_Incomplete_Dependents (N, T, Prev);
2815 Generate_Reference (Prev, Def_Id, 'c');
2816 Set_Completion_Referenced (Def_Id);
2818 -- If not private type or incomplete type completion, this is a real
2819 -- definition of a new entity, so record it.
2822 Generate_Definition (Def_Id);
2825 -- Propagate any pending access types whose finalization masters need to
2826 -- be fully initialized from the partial to the full view. Guard against
2827 -- an illegal full view that remains unanalyzed.
2829 if Is_Type (Def_Id) and then Is_Incomplete_Or_Private_Type (Prev) then
2830 Set_Pending_Access_Types (Def_Id, Pending_Access_Types (Prev));
2833 if Chars (Scope (Def_Id)) = Name_System
2834 and then Chars (Def_Id) = Name_Address
2835 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
2837 Set_Is_Descendent_Of_Address (Def_Id);
2838 Set_Is_Descendent_Of_Address (Base_Type (Def_Id));
2839 Set_Is_Descendent_Of_Address (Prev);
2842 Set_Optimize_Alignment_Flags (Def_Id);
2843 Check_Eliminated (Def_Id);
2845 -- If the declaration is a completion and aspects are present, apply
2846 -- them to the entity for the type which is currently the partial
2847 -- view, but which is the one that will be frozen.
2849 if Has_Aspects (N) then
2851 -- In most cases the partial view is a private type, and both views
2852 -- appear in different declarative parts. In the unusual case where
2853 -- the partial view is incomplete, perform the analysis on the
2854 -- full view, to prevent freezing anomalies with the corresponding
2855 -- class-wide type, which otherwise might be frozen before the
2856 -- dispatch table is built.
2859 and then Ekind (Prev) /= E_Incomplete_Type
2861 Analyze_Aspect_Specifications (N, Prev);
2866 Analyze_Aspect_Specifications (N, Def_Id);
2869 end Analyze_Full_Type_Declaration;
2871 ----------------------------------
2872 -- Analyze_Incomplete_Type_Decl --
2873 ----------------------------------
2875 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
2876 F : constant Boolean := Is_Pure (Current_Scope);
2880 Check_SPARK_05_Restriction ("incomplete type is not allowed", N);
2882 Generate_Definition (Defining_Identifier (N));
2884 -- Process an incomplete declaration. The identifier must not have been
2885 -- declared already in the scope. However, an incomplete declaration may
2886 -- appear in the private part of a package, for a private type that has
2887 -- already been declared.
2889 -- In this case, the discriminants (if any) must match
2891 T := Find_Type_Name (N);
2893 Set_Ekind (T, E_Incomplete_Type);
2894 Init_Size_Align (T);
2895 Set_Is_First_Subtype (T, True);
2898 -- An incomplete type declared within a Ghost region is automatically
2899 -- Ghost (SPARK RM 6.9(2)).
2901 if Ghost_Mode > None then
2902 Set_Is_Ghost_Entity (T);
2905 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
2906 -- incomplete types.
2908 if Tagged_Present (N) then
2909 Set_Is_Tagged_Type (T, True);
2910 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
2911 Make_Class_Wide_Type (T);
2912 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2917 Set_Stored_Constraint (T, No_Elist);
2919 if Present (Discriminant_Specifications (N)) then
2920 Process_Discriminants (N);
2925 -- If the type has discriminants, non-trivial subtypes may be
2926 -- declared before the full view of the type. The full views of those
2927 -- subtypes will be built after the full view of the type.
2929 Set_Private_Dependents (T, New_Elmt_List);
2931 end Analyze_Incomplete_Type_Decl;
2933 -----------------------------------
2934 -- Analyze_Interface_Declaration --
2935 -----------------------------------
2937 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
2938 CW : constant Entity_Id := Class_Wide_Type (T);
2941 Set_Is_Tagged_Type (T);
2942 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
2944 Set_Is_Limited_Record (T, Limited_Present (Def)
2945 or else Task_Present (Def)
2946 or else Protected_Present (Def)
2947 or else Synchronized_Present (Def));
2949 -- Type is abstract if full declaration carries keyword, or if previous
2950 -- partial view did.
2952 Set_Is_Abstract_Type (T);
2953 Set_Is_Interface (T);
2955 -- Type is a limited interface if it includes the keyword limited, task,
2956 -- protected, or synchronized.
2958 Set_Is_Limited_Interface
2959 (T, Limited_Present (Def)
2960 or else Protected_Present (Def)
2961 or else Synchronized_Present (Def)
2962 or else Task_Present (Def));
2964 Set_Interfaces (T, New_Elmt_List);
2965 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2967 -- Complete the decoration of the class-wide entity if it was already
2968 -- built (i.e. during the creation of the limited view)
2970 if Present (CW) then
2971 Set_Is_Interface (CW);
2972 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
2975 -- Check runtime support for synchronized interfaces
2977 if VM_Target = No_VM
2978 and then (Is_Task_Interface (T)
2979 or else Is_Protected_Interface (T)
2980 or else Is_Synchronized_Interface (T))
2981 and then not RTE_Available (RE_Select_Specific_Data)
2983 Error_Msg_CRT ("synchronized interfaces", T);
2985 end Analyze_Interface_Declaration;
2987 -----------------------------
2988 -- Analyze_Itype_Reference --
2989 -----------------------------
2991 -- Nothing to do. This node is placed in the tree only for the benefit of
2992 -- back end processing, and has no effect on the semantic processing.
2994 procedure Analyze_Itype_Reference (N : Node_Id) is
2996 pragma Assert (Is_Itype (Itype (N)));
2998 end Analyze_Itype_Reference;
3000 --------------------------------
3001 -- Analyze_Number_Declaration --
3002 --------------------------------
3004 procedure Analyze_Number_Declaration (N : Node_Id) is
3005 Id : constant Entity_Id := Defining_Identifier (N);
3006 E : constant Node_Id := Expression (N);
3008 Index : Interp_Index;
3012 -- The number declaration may be subject to pragma Ghost with policy
3013 -- Ignore. Set the mode now to ensure that any nodes generated during
3014 -- analysis and expansion are properly flagged as ignored Ghost.
3018 Generate_Definition (Id);
3021 -- A number declared within a Ghost region is automatically Ghost
3022 -- (SPARK RM 6.9(2)).
3024 if Ghost_Mode > None then
3025 Set_Is_Ghost_Entity (Id);
3028 -- This is an optimization of a common case of an integer literal
3030 if Nkind (E) = N_Integer_Literal then
3031 Set_Is_Static_Expression (E, True);
3032 Set_Etype (E, Universal_Integer);
3034 Set_Etype (Id, Universal_Integer);
3035 Set_Ekind (Id, E_Named_Integer);
3036 Set_Is_Frozen (Id, True);
3040 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3042 -- Process expression, replacing error by integer zero, to avoid
3043 -- cascaded errors or aborts further along in the processing
3045 -- Replace Error by integer zero, which seems least likely to cause
3049 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
3050 Set_Error_Posted (E);
3055 -- Verify that the expression is static and numeric. If
3056 -- the expression is overloaded, we apply the preference
3057 -- rule that favors root numeric types.
3059 if not Is_Overloaded (E) then
3061 if Has_Dynamic_Predicate_Aspect (T) then
3063 ("subtype has dynamic predicate, "
3064 & "not allowed in number declaration", N);
3070 Get_First_Interp (E, Index, It);
3071 while Present (It.Typ) loop
3072 if (Is_Integer_Type (It.Typ) or else Is_Real_Type (It.Typ))
3073 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
3075 if T = Any_Type then
3078 elsif It.Typ = Universal_Real
3080 It.Typ = Universal_Integer
3082 -- Choose universal interpretation over any other
3089 Get_Next_Interp (Index, It);
3093 if Is_Integer_Type (T) then
3095 Set_Etype (Id, Universal_Integer);
3096 Set_Ekind (Id, E_Named_Integer);
3098 elsif Is_Real_Type (T) then
3100 -- Because the real value is converted to universal_real, this is a
3101 -- legal context for a universal fixed expression.
3103 if T = Universal_Fixed then
3105 Loc : constant Source_Ptr := Sloc (N);
3106 Conv : constant Node_Id := Make_Type_Conversion (Loc,
3108 New_Occurrence_Of (Universal_Real, Loc),
3109 Expression => Relocate_Node (E));
3116 elsif T = Any_Fixed then
3117 Error_Msg_N ("illegal context for mixed mode operation", E);
3119 -- Expression is of the form : universal_fixed * integer. Try to
3120 -- resolve as universal_real.
3122 T := Universal_Real;
3127 Set_Etype (Id, Universal_Real);
3128 Set_Ekind (Id, E_Named_Real);
3131 Wrong_Type (E, Any_Numeric);
3135 Set_Ekind (Id, E_Constant);
3136 Set_Never_Set_In_Source (Id, True);
3137 Set_Is_True_Constant (Id, True);
3141 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
3142 Set_Etype (E, Etype (Id));
3145 if not Is_OK_Static_Expression (E) then
3146 Flag_Non_Static_Expr
3147 ("non-static expression used in number declaration!", E);
3148 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
3149 Set_Etype (E, Any_Type);
3151 end Analyze_Number_Declaration;
3153 -----------------------------
3154 -- Analyze_Object_Contract --
3155 -----------------------------
3157 procedure Analyze_Object_Contract (Obj_Id : Entity_Id) is
3158 Obj_Typ : constant Entity_Id := Etype (Obj_Id);
3159 AR_Val : Boolean := False;
3160 AW_Val : Boolean := False;
3161 ER_Val : Boolean := False;
3162 EW_Val : Boolean := False;
3164 Seen : Boolean := False;
3167 -- The loop parameter in an element iterator over a formal container
3168 -- is declared with an object declaration but no contracts apply.
3170 if Ekind (Obj_Id) = E_Loop_Parameter then
3174 if Ekind (Obj_Id) = E_Constant then
3176 -- A constant cannot be effectively volatile. This check is only
3177 -- relevant with SPARK_Mode on as it is not a standard Ada legality
3178 -- rule. Do not flag internally-generated constants that map generic
3179 -- formals to actuals in instantiations (SPARK RM 7.1.3(6)).
3182 and then Is_Effectively_Volatile (Obj_Id)
3183 and then No (Corresponding_Generic_Association (Parent (Obj_Id)))
3185 -- Don't give this for internally generated entities (such as the
3186 -- FIRST and LAST temporaries generated for bounds).
3188 and then Comes_From_Source (Obj_Id)
3190 Error_Msg_N ("constant cannot be volatile", Obj_Id);
3193 else pragma Assert (Ekind (Obj_Id) = E_Variable);
3195 -- The following checks are only relevant when SPARK_Mode is on as
3196 -- they are not standard Ada legality rules. Internally generated
3197 -- temporaries are ignored.
3199 if SPARK_Mode = On and then Comes_From_Source (Obj_Id) then
3200 if Is_Effectively_Volatile (Obj_Id) then
3202 -- The declaration of an effectively volatile object must
3203 -- appear at the library level (SPARK RM 7.1.3(7), C.6(6)).
3205 if not Is_Library_Level_Entity (Obj_Id) then
3207 ("volatile variable & must be declared at library level",
3210 -- An object of a discriminated type cannot be effectively
3211 -- volatile (SPARK RM C.6(4)).
3213 elsif Has_Discriminants (Obj_Typ) then
3215 ("discriminated object & cannot be volatile", Obj_Id);
3217 -- An object of a tagged type cannot be effectively volatile
3218 -- (SPARK RM C.6(5)).
3220 elsif Is_Tagged_Type (Obj_Typ) then
3221 Error_Msg_N ("tagged object & cannot be volatile", Obj_Id);
3224 -- The object is not effectively volatile
3227 -- A non-effectively volatile object cannot have effectively
3228 -- volatile components (SPARK RM 7.1.3(7)).
3230 if not Is_Effectively_Volatile (Obj_Id)
3231 and then Has_Volatile_Component (Obj_Typ)
3234 ("non-volatile object & cannot have volatile components",
3240 if Is_Ghost_Entity (Obj_Id) then
3242 -- A Ghost object cannot be effectively volatile (SPARK RM 6.9(8))
3244 if Is_Effectively_Volatile (Obj_Id) then
3245 Error_Msg_N ("ghost variable & cannot be volatile", Obj_Id);
3247 -- A Ghost object cannot be imported or exported (SPARK RM 6.9(8))
3249 elsif Is_Imported (Obj_Id) then
3250 Error_Msg_N ("ghost object & cannot be imported", Obj_Id);
3252 elsif Is_Exported (Obj_Id) then
3253 Error_Msg_N ("ghost object & cannot be exported", Obj_Id);
3257 -- Analyze all external properties
3259 Prag := Get_Pragma (Obj_Id, Pragma_Async_Readers);
3261 if Present (Prag) then
3262 Analyze_External_Property_In_Decl_Part (Prag, AR_Val);
3266 Prag := Get_Pragma (Obj_Id, Pragma_Async_Writers);
3268 if Present (Prag) then
3269 Analyze_External_Property_In_Decl_Part (Prag, AW_Val);
3273 Prag := Get_Pragma (Obj_Id, Pragma_Effective_Reads);
3275 if Present (Prag) then
3276 Analyze_External_Property_In_Decl_Part (Prag, ER_Val);
3280 Prag := Get_Pragma (Obj_Id, Pragma_Effective_Writes);
3282 if Present (Prag) then
3283 Analyze_External_Property_In_Decl_Part (Prag, EW_Val);
3287 -- Verify the mutual interaction of the various external properties
3290 Check_External_Properties (Obj_Id, AR_Val, AW_Val, ER_Val, EW_Val);
3293 -- Check whether the lack of indicator Part_Of agrees with the
3294 -- placement of the variable with respect to the state space.
3296 Prag := Get_Pragma (Obj_Id, Pragma_Part_Of);
3299 Check_Missing_Part_Of (Obj_Id);
3303 -- A ghost object cannot be imported or exported (SPARK RM 6.9(8))
3305 if Is_Ghost_Entity (Obj_Id) then
3306 if Is_Exported (Obj_Id) then
3307 Error_Msg_N ("ghost object & cannot be exported", Obj_Id);
3309 elsif Is_Imported (Obj_Id) then
3310 Error_Msg_N ("ghost object & cannot be imported", Obj_Id);
3313 end Analyze_Object_Contract;
3315 --------------------------------
3316 -- Analyze_Object_Declaration --
3317 --------------------------------
3319 procedure Analyze_Object_Declaration (N : Node_Id) is
3320 Loc : constant Source_Ptr := Sloc (N);
3321 Id : constant Entity_Id := Defining_Identifier (N);
3325 E : Node_Id := Expression (N);
3326 -- E is set to Expression (N) throughout this routine. When
3327 -- Expression (N) is modified, E is changed accordingly.
3329 Prev_Entity : Entity_Id := Empty;
3331 function Count_Tasks (T : Entity_Id) return Uint;
3332 -- This function is called when a non-generic library level object of a
3333 -- task type is declared. Its function is to count the static number of
3334 -- tasks declared within the type (it is only called if Has_Tasks is set
3335 -- for T). As a side effect, if an array of tasks with non-static bounds
3336 -- or a variant record type is encountered, Check_Restrictions is called
3337 -- indicating the count is unknown.
3339 function Delayed_Aspect_Present return Boolean;
3340 -- If the declaration has an expression that is an aggregate, and it
3341 -- has aspects that require delayed analysis, the resolution of the
3342 -- aggregate must be deferred to the freeze point of the objet. This
3343 -- special processing was created for address clauses, but it must
3344 -- also apply to Alignment. This must be done before the aspect
3345 -- specifications are analyzed because we must handle the aggregate
3346 -- before the analysis of the object declaration is complete.
3348 -- Any other relevant delayed aspects on object declarations ???
3354 function Count_Tasks (T : Entity_Id) return Uint is
3360 if Is_Task_Type (T) then
3363 elsif Is_Record_Type (T) then
3364 if Has_Discriminants (T) then
3365 Check_Restriction (Max_Tasks, N);
3370 C := First_Component (T);
3371 while Present (C) loop
3372 V := V + Count_Tasks (Etype (C));
3379 elsif Is_Array_Type (T) then
3380 X := First_Index (T);
3381 V := Count_Tasks (Component_Type (T));
3382 while Present (X) loop
3385 if not Is_OK_Static_Subtype (C) then
3386 Check_Restriction (Max_Tasks, N);
3389 V := V * (UI_Max (Uint_0,
3390 Expr_Value (Type_High_Bound (C)) -
3391 Expr_Value (Type_Low_Bound (C)) + Uint_1));
3404 ----------------------------
3405 -- Delayed_Aspect_Present --
3406 ----------------------------
3408 function Delayed_Aspect_Present return Boolean is
3413 if Present (Aspect_Specifications (N)) then
3414 A := First (Aspect_Specifications (N));
3415 A_Id := Get_Aspect_Id (Chars (Identifier (A)));
3416 while Present (A) loop
3417 if A_Id = Aspect_Alignment or else A_Id = Aspect_Address then
3426 end Delayed_Aspect_Present;
3428 -- Start of processing for Analyze_Object_Declaration
3431 -- There are three kinds of implicit types generated by an
3432 -- object declaration:
3434 -- 1. Those generated by the original Object Definition
3436 -- 2. Those generated by the Expression
3438 -- 3. Those used to constrain the Object Definition with the
3439 -- expression constraints when the definition is unconstrained.
3441 -- They must be generated in this order to avoid order of elaboration
3442 -- issues. Thus the first step (after entering the name) is to analyze
3443 -- the object definition.
3445 if Constant_Present (N) then
3446 Prev_Entity := Current_Entity_In_Scope (Id);
3448 if Present (Prev_Entity)
3450 -- If the homograph is an implicit subprogram, it is overridden
3451 -- by the current declaration.
3453 ((Is_Overloadable (Prev_Entity)
3454 and then Is_Inherited_Operation (Prev_Entity))
3456 -- The current object is a discriminal generated for an entry
3457 -- family index. Even though the index is a constant, in this
3458 -- particular context there is no true constant redeclaration.
3459 -- Enter_Name will handle the visibility.
3462 (Is_Discriminal (Id)
3463 and then Ekind (Discriminal_Link (Id)) =
3464 E_Entry_Index_Parameter)
3466 -- The current object is the renaming for a generic declared
3467 -- within the instance.
3470 (Ekind (Prev_Entity) = E_Package
3471 and then Nkind (Parent (Prev_Entity)) =
3472 N_Package_Renaming_Declaration
3473 and then not Comes_From_Source (Prev_Entity)
3475 Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
3477 Prev_Entity := Empty;
3481 -- The object declaration may be subject to pragma Ghost with policy
3482 -- Ignore. Set the mode now to ensure that any nodes generated during
3483 -- analysis and expansion are properly flagged as ignored Ghost.
3485 Set_Ghost_Mode (N, Prev_Entity);
3487 if Present (Prev_Entity) then
3488 Constant_Redeclaration (Id, N, T);
3490 Generate_Reference (Prev_Entity, Id, 'c');
3491 Set_Completion_Referenced (Id);
3493 if Error_Posted (N) then
3495 -- Type mismatch or illegal redeclaration, Do not analyze
3496 -- expression to avoid cascaded errors.
3498 T := Find_Type_Of_Object (Object_Definition (N), N);
3500 Set_Ekind (Id, E_Variable);
3504 -- In the normal case, enter identifier at the start to catch premature
3505 -- usage in the initialization expression.
3508 Generate_Definition (Id);
3511 Mark_Coextensions (N, Object_Definition (N));
3513 T := Find_Type_Of_Object (Object_Definition (N), N);
3515 if Nkind (Object_Definition (N)) = N_Access_Definition
3517 (Access_To_Subprogram_Definition (Object_Definition (N)))
3518 and then Protected_Present
3519 (Access_To_Subprogram_Definition (Object_Definition (N)))
3521 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
3524 if Error_Posted (Id) then
3526 Set_Ekind (Id, E_Variable);
3531 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
3532 -- out some static checks
3534 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
3536 -- In case of aggregates we must also take care of the correct
3537 -- initialization of nested aggregates bug this is done at the
3538 -- point of the analysis of the aggregate (see sem_aggr.adb).
3540 if Present (Expression (N))
3541 and then Nkind (Expression (N)) = N_Aggregate
3547 Save_Typ : constant Entity_Id := Etype (Id);
3549 Set_Etype (Id, T); -- Temp. decoration for static checks
3550 Null_Exclusion_Static_Checks (N);
3551 Set_Etype (Id, Save_Typ);
3556 -- Object is marked pure if it is in a pure scope
3558 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3560 -- If deferred constant, make sure context is appropriate. We detect
3561 -- a deferred constant as a constant declaration with no expression.
3562 -- A deferred constant can appear in a package body if its completion
3563 -- is by means of an interface pragma.
3565 if Constant_Present (N) and then No (E) then
3567 -- A deferred constant may appear in the declarative part of the
3568 -- following constructs:
3572 -- extended return statements
3575 -- subprogram bodies
3578 -- When declared inside a package spec, a deferred constant must be
3579 -- completed by a full constant declaration or pragma Import. In all
3580 -- other cases, the only proper completion is pragma Import. Extended
3581 -- return statements are flagged as invalid contexts because they do
3582 -- not have a declarative part and so cannot accommodate the pragma.
3584 if Ekind (Current_Scope) = E_Return_Statement then
3586 ("invalid context for deferred constant declaration (RM 7.4)",
3589 ("\declaration requires an initialization expression",
3591 Set_Constant_Present (N, False);
3593 -- In Ada 83, deferred constant must be of private type
3595 elsif not Is_Private_Type (T) then
3596 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
3598 ("(Ada 83) deferred constant must be private type", N);
3602 -- If not a deferred constant, then the object declaration freezes
3603 -- its type, unless the object is of an anonymous type and has delayed
3604 -- aspects. In that case the type is frozen when the object itself is.
3607 Check_Fully_Declared (T, N);
3609 if Has_Delayed_Aspects (Id)
3610 and then Is_Array_Type (T)
3611 and then Is_Itype (T)
3613 Set_Has_Delayed_Freeze (T);
3615 Freeze_Before (N, T);
3619 -- If the object was created by a constrained array definition, then
3620 -- set the link in both the anonymous base type and anonymous subtype
3621 -- that are built to represent the array type to point to the object.
3623 if Nkind (Object_Definition (Declaration_Node (Id))) =
3624 N_Constrained_Array_Definition
3626 Set_Related_Array_Object (T, Id);
3627 Set_Related_Array_Object (Base_Type (T), Id);
3630 -- Special checks for protected objects not at library level
3632 if Is_Protected_Type (T)
3633 and then not Is_Library_Level_Entity (Id)
3635 Check_Restriction (No_Local_Protected_Objects, Id);
3637 -- Protected objects with interrupt handlers must be at library level
3639 -- Ada 2005: This test is not needed (and the corresponding clause
3640 -- in the RM is removed) because accessibility checks are sufficient
3641 -- to make handlers not at the library level illegal.
3643 -- AI05-0303: The AI is in fact a binding interpretation, and thus
3644 -- applies to the '95 version of the language as well.
3646 if Has_Interrupt_Handler (T) and then Ada_Version < Ada_95 then
3648 ("interrupt object can only be declared at library level", Id);
3652 -- The actual subtype of the object is the nominal subtype, unless
3653 -- the nominal one is unconstrained and obtained from the expression.
3657 -- These checks should be performed before the initialization expression
3658 -- is considered, so that the Object_Definition node is still the same
3659 -- as in source code.
3661 -- In SPARK, the nominal subtype is always given by a subtype mark
3662 -- and must not be unconstrained. (The only exception to this is the
3663 -- acceptance of declarations of constants of type String.)
3665 if not Nkind_In (Object_Definition (N), N_Expanded_Name, N_Identifier)
3667 Check_SPARK_05_Restriction
3668 ("subtype mark required", Object_Definition (N));
3670 elsif Is_Array_Type (T)
3671 and then not Is_Constrained (T)
3672 and then T /= Standard_String
3674 Check_SPARK_05_Restriction
3675 ("subtype mark of constrained type expected",
3676 Object_Definition (N));
3679 -- There are no aliased objects in SPARK
3681 if Aliased_Present (N) then
3682 Check_SPARK_05_Restriction ("aliased object is not allowed", N);
3685 -- Process initialization expression if present and not in error
3687 if Present (E) and then E /= Error then
3689 -- Generate an error in case of CPP class-wide object initialization.
3690 -- Required because otherwise the expansion of the class-wide
3691 -- assignment would try to use 'size to initialize the object
3692 -- (primitive that is not available in CPP tagged types).
3694 if Is_Class_Wide_Type (Act_T)
3696 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3698 (Present (Full_View (Root_Type (Etype (Act_T))))
3700 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3703 ("predefined assignment not available for 'C'P'P tagged types",
3707 Mark_Coextensions (N, E);
3710 -- In case of errors detected in the analysis of the expression,
3711 -- decorate it with the expected type to avoid cascaded errors
3713 if No (Etype (E)) then
3717 -- If an initialization expression is present, then we set the
3718 -- Is_True_Constant flag. It will be reset if this is a variable
3719 -- and it is indeed modified.
3721 Set_Is_True_Constant (Id, True);
3723 -- If we are analyzing a constant declaration, set its completion
3724 -- flag after analyzing and resolving the expression.
3726 if Constant_Present (N) then
3727 Set_Has_Completion (Id);
3730 -- Set type and resolve (type may be overridden later on). Note:
3731 -- Ekind (Id) must still be E_Void at this point so that incorrect
3732 -- early usage within E is properly diagnosed.
3736 -- If the expression is an aggregate we must look ahead to detect
3737 -- the possible presence of an address clause, and defer resolution
3738 -- and expansion of the aggregate to the freeze point of the entity.
3740 if Comes_From_Source (N)
3741 and then Expander_Active
3742 and then Nkind (E) = N_Aggregate
3743 and then (Present (Following_Address_Clause (N))
3744 or else Delayed_Aspect_Present)
3752 -- No further action needed if E is a call to an inlined function
3753 -- which returns an unconstrained type and it has been expanded into
3754 -- a procedure call. In that case N has been replaced by an object
3755 -- declaration without initializing expression and it has been
3756 -- analyzed (see Expand_Inlined_Call).
3758 if Back_End_Inlining
3759 and then Expander_Active
3760 and then Nkind (E) = N_Function_Call
3761 and then Nkind (Name (E)) in N_Has_Entity
3762 and then Is_Inlined (Entity (Name (E)))
3763 and then not Is_Constrained (Etype (E))
3764 and then Analyzed (N)
3765 and then No (Expression (N))
3770 -- If E is null and has been replaced by an N_Raise_Constraint_Error
3771 -- node (which was marked already-analyzed), we need to set the type
3772 -- to something other than Any_Access in order to keep gigi happy.
3774 if Etype (E) = Any_Access then
3778 -- If the object is an access to variable, the initialization
3779 -- expression cannot be an access to constant.
3781 if Is_Access_Type (T)
3782 and then not Is_Access_Constant (T)
3783 and then Is_Access_Type (Etype (E))
3784 and then Is_Access_Constant (Etype (E))
3787 ("access to variable cannot be initialized with an "
3788 & "access-to-constant expression", E);
3791 if not Assignment_OK (N) then
3792 Check_Initialization (T, E);
3795 Check_Unset_Reference (E);
3797 -- If this is a variable, then set current value. If this is a
3798 -- declared constant of a scalar type with a static expression,
3799 -- indicate that it is always valid.
3801 if not Constant_Present (N) then
3802 if Compile_Time_Known_Value (E) then
3803 Set_Current_Value (Id, E);
3806 elsif Is_Scalar_Type (T) and then Is_OK_Static_Expression (E) then
3807 Set_Is_Known_Valid (Id);
3810 -- Deal with setting of null flags
3812 if Is_Access_Type (T) then
3813 if Known_Non_Null (E) then
3814 Set_Is_Known_Non_Null (Id, True);
3815 elsif Known_Null (E) and then not Can_Never_Be_Null (Id) then
3816 Set_Is_Known_Null (Id, True);
3820 -- Check incorrect use of dynamically tagged expressions
3822 if Is_Tagged_Type (T) then
3823 Check_Dynamically_Tagged_Expression
3829 Apply_Scalar_Range_Check (E, T);
3830 Apply_Static_Length_Check (E, T);
3832 if Nkind (Original_Node (N)) = N_Object_Declaration
3833 and then Comes_From_Source (Original_Node (N))
3835 -- Only call test if needed
3837 and then Restriction_Check_Required (SPARK_05)
3838 and then not Is_SPARK_05_Initialization_Expr (Original_Node (E))
3840 Check_SPARK_05_Restriction
3841 ("initialization expression is not appropriate", E);
3844 -- A formal parameter of a specific tagged type whose related
3845 -- subprogram is subject to pragma Extensions_Visible with value
3846 -- "False" cannot be implicitly converted to a class-wide type by
3847 -- means of an initialization expression (SPARK RM 6.1.7(3)).
3849 if Is_Class_Wide_Type (T) and then Is_EVF_Expression (E) then
3851 ("formal parameter with Extensions_Visible False cannot be "
3852 & "implicitly converted to class-wide type", E);
3856 -- If the No_Streams restriction is set, check that the type of the
3857 -- object is not, and does not contain, any subtype derived from
3858 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
3859 -- Has_Stream just for efficiency reasons. There is no point in
3860 -- spending time on a Has_Stream check if the restriction is not set.
3862 if Restriction_Check_Required (No_Streams) then
3863 if Has_Stream (T) then
3864 Check_Restriction (No_Streams, N);
3868 -- Deal with predicate check before we start to do major rewriting. It
3869 -- is OK to initialize and then check the initialized value, since the
3870 -- object goes out of scope if we get a predicate failure. Note that we
3871 -- do this in the analyzer and not the expander because the analyzer
3872 -- does some substantial rewriting in some cases.
3874 -- We need a predicate check if the type has predicates, and if either
3875 -- there is an initializing expression, or for default initialization
3876 -- when we have at least one case of an explicit default initial value
3877 -- and then this is not an internal declaration whose initialization
3878 -- comes later (as for an aggregate expansion).
3880 if not Suppress_Assignment_Checks (N)
3881 and then Present (Predicate_Function (T))
3882 and then not No_Initialization (N)
3886 Is_Partially_Initialized_Type (T, Include_Implicit => False))
3888 -- If the type has a static predicate and the expression is known at
3889 -- compile time, see if the expression satisfies the predicate.
3892 Check_Expression_Against_Static_Predicate (E, T);
3896 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
3899 -- Case of unconstrained type
3901 if Is_Indefinite_Subtype (T) then
3903 -- In SPARK, a declaration of unconstrained type is allowed
3904 -- only for constants of type string.
3906 if Is_String_Type (T) and then not Constant_Present (N) then
3907 Check_SPARK_05_Restriction
3908 ("declaration of object of unconstrained type not allowed", N);
3911 -- Nothing to do in deferred constant case
3913 if Constant_Present (N) and then No (E) then
3916 -- Case of no initialization present
3919 if No_Initialization (N) then
3922 elsif Is_Class_Wide_Type (T) then
3924 ("initialization required in class-wide declaration ", N);
3928 ("unconstrained subtype not allowed (need initialization)",
3929 Object_Definition (N));
3931 if Is_Record_Type (T) and then Has_Discriminants (T) then
3933 ("\provide initial value or explicit discriminant values",
3934 Object_Definition (N));
3937 ("\or give default discriminant values for type&",
3938 Object_Definition (N), T);
3940 elsif Is_Array_Type (T) then
3942 ("\provide initial value or explicit array bounds",
3943 Object_Definition (N));
3947 -- Case of initialization present but in error. Set initial
3948 -- expression as absent (but do not make above complaints)
3950 elsif E = Error then
3951 Set_Expression (N, Empty);
3954 -- Case of initialization present
3957 -- Check restrictions in Ada 83
3959 if not Constant_Present (N) then
3961 -- Unconstrained variables not allowed in Ada 83 mode
3963 if Ada_Version = Ada_83
3964 and then Comes_From_Source (Object_Definition (N))
3967 ("(Ada 83) unconstrained variable not allowed",
3968 Object_Definition (N));
3972 -- Now we constrain the variable from the initializing expression
3974 -- If the expression is an aggregate, it has been expanded into
3975 -- individual assignments. Retrieve the actual type from the
3976 -- expanded construct.
3978 if Is_Array_Type (T)
3979 and then No_Initialization (N)
3980 and then Nkind (Original_Node (E)) = N_Aggregate
3984 -- In case of class-wide interface object declarations we delay
3985 -- the generation of the equivalent record type declarations until
3986 -- its expansion because there are cases in they are not required.
3988 elsif Is_Interface (T) then
3991 -- In GNATprove mode, Expand_Subtype_From_Expr does nothing. Thus,
3992 -- we should prevent the generation of another Itype with the
3993 -- same name as the one already generated, or we end up with
3994 -- two identical types in GNATprove.
3996 elsif GNATprove_Mode then
3999 -- If the type is an unchecked union, no subtype can be built from
4000 -- the expression. Rewrite declaration as a renaming, which the
4001 -- back-end can handle properly. This is a rather unusual case,
4002 -- because most unchecked_union declarations have default values
4003 -- for discriminants and are thus not indefinite.
4005 elsif Is_Unchecked_Union (T) then
4006 if Constant_Present (N) or else Nkind (E) = N_Function_Call then
4007 Set_Ekind (Id, E_Constant);
4009 Set_Ekind (Id, E_Variable);
4012 -- An object declared within a Ghost region is automatically
4013 -- Ghost (SPARK RM 6.9(2)).
4015 if Comes_From_Source (Id) and then Ghost_Mode > None then
4016 Set_Is_Ghost_Entity (Id);
4018 -- The Ghost policy in effect at the point of declaration
4019 -- and at the point of completion must match
4020 -- (SPARK RM 6.9(15)).
4022 if Present (Prev_Entity)
4023 and then Is_Ghost_Entity (Prev_Entity)
4025 Check_Ghost_Completion (Prev_Entity, Id);
4030 Make_Object_Renaming_Declaration (Loc,
4031 Defining_Identifier => Id,
4032 Subtype_Mark => New_Occurrence_Of (T, Loc),
4035 Set_Renamed_Object (Id, E);
4036 Freeze_Before (N, T);
4041 Expand_Subtype_From_Expr (N, T, Object_Definition (N), E);
4042 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
4045 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
4047 if Aliased_Present (N) then
4048 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4051 Freeze_Before (N, Act_T);
4052 Freeze_Before (N, T);
4055 elsif Is_Array_Type (T)
4056 and then No_Initialization (N)
4057 and then Nkind (Original_Node (E)) = N_Aggregate
4059 if not Is_Entity_Name (Object_Definition (N)) then
4061 Check_Compile_Time_Size (Act_T);
4063 if Aliased_Present (N) then
4064 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
4068 -- When the given object definition and the aggregate are specified
4069 -- independently, and their lengths might differ do a length check.
4070 -- This cannot happen if the aggregate is of the form (others =>...)
4072 if not Is_Constrained (T) then
4075 elsif Nkind (E) = N_Raise_Constraint_Error then
4077 -- Aggregate is statically illegal. Place back in declaration
4079 Set_Expression (N, E);
4080 Set_No_Initialization (N, False);
4082 elsif T = Etype (E) then
4085 elsif Nkind (E) = N_Aggregate
4086 and then Present (Component_Associations (E))
4087 and then Present (Choices (First (Component_Associations (E))))
4088 and then Nkind (First
4089 (Choices (First (Component_Associations (E))))) = N_Others_Choice
4094 Apply_Length_Check (E, T);
4097 -- If the type is limited unconstrained with defaulted discriminants and
4098 -- there is no expression, then the object is constrained by the
4099 -- defaults, so it is worthwhile building the corresponding subtype.
4101 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
4102 and then not Is_Constrained (T)
4103 and then Has_Discriminants (T)
4106 Act_T := Build_Default_Subtype (T, N);
4108 -- Ada 2005: A limited object may be initialized by means of an
4109 -- aggregate. If the type has default discriminants it has an
4110 -- unconstrained nominal type, Its actual subtype will be obtained
4111 -- from the aggregate, and not from the default discriminants.
4116 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
4118 elsif Nkind (E) = N_Function_Call
4119 and then Constant_Present (N)
4120 and then Has_Unconstrained_Elements (Etype (E))
4122 -- The back-end has problems with constants of a discriminated type
4123 -- with defaults, if the initial value is a function call. We
4124 -- generate an intermediate temporary that will receive a reference
4125 -- to the result of the call. The initialization expression then
4126 -- becomes a dereference of that temporary.
4128 Remove_Side_Effects (E);
4130 -- If this is a constant declaration of an unconstrained type and
4131 -- the initialization is an aggregate, we can use the subtype of the
4132 -- aggregate for the declared entity because it is immutable.
4134 elsif not Is_Constrained (T)
4135 and then Has_Discriminants (T)
4136 and then Constant_Present (N)
4137 and then not Has_Unchecked_Union (T)
4138 and then Nkind (E) = N_Aggregate
4143 -- Check No_Wide_Characters restriction
4145 Check_Wide_Character_Restriction (T, Object_Definition (N));
4147 -- Indicate this is not set in source. Certainly true for constants, and
4148 -- true for variables so far (will be reset for a variable if and when
4149 -- we encounter a modification in the source).
4151 Set_Never_Set_In_Source (Id);
4153 -- Now establish the proper kind and type of the object
4155 if Constant_Present (N) then
4156 Set_Ekind (Id, E_Constant);
4157 Set_Is_True_Constant (Id);
4160 Set_Ekind (Id, E_Variable);
4162 -- A variable is set as shared passive if it appears in a shared
4163 -- passive package, and is at the outer level. This is not done for
4164 -- entities generated during expansion, because those are always
4165 -- manipulated locally.
4167 if Is_Shared_Passive (Current_Scope)
4168 and then Is_Library_Level_Entity (Id)
4169 and then Comes_From_Source (Id)
4171 Set_Is_Shared_Passive (Id);
4172 Check_Shared_Var (Id, T, N);
4175 -- Set Has_Initial_Value if initializing expression present. Note
4176 -- that if there is no initializing expression, we leave the state
4177 -- of this flag unchanged (usually it will be False, but notably in
4178 -- the case of exception choice variables, it will already be true).
4181 Set_Has_Initial_Value (Id);
4185 -- Initialize alignment and size and capture alignment setting
4187 Init_Alignment (Id);
4189 Set_Optimize_Alignment_Flags (Id);
4191 -- An object declared within a Ghost region is automatically Ghost
4192 -- (SPARK RM 6.9(2)).
4194 if Comes_From_Source (Id)
4195 and then (Ghost_Mode > None
4196 or else (Present (Prev_Entity)
4197 and then Is_Ghost_Entity (Prev_Entity)))
4199 Set_Is_Ghost_Entity (Id);
4201 -- The Ghost policy in effect at the point of declaration and at the
4202 -- point of completion must match (SPARK RM 6.9(16)).
4204 if Present (Prev_Entity) and then Is_Ghost_Entity (Prev_Entity) then
4205 Check_Ghost_Completion (Prev_Entity, Id);
4209 -- Deal with aliased case
4211 if Aliased_Present (N) then
4212 Set_Is_Aliased (Id);
4214 -- If the object is aliased and the type is unconstrained with
4215 -- defaulted discriminants and there is no expression, then the
4216 -- object is constrained by the defaults, so it is worthwhile
4217 -- building the corresponding subtype.
4219 -- Ada 2005 (AI-363): If the aliased object is discriminated and
4220 -- unconstrained, then only establish an actual subtype if the
4221 -- nominal subtype is indefinite. In definite cases the object is
4222 -- unconstrained in Ada 2005.
4225 and then Is_Record_Type (T)
4226 and then not Is_Constrained (T)
4227 and then Has_Discriminants (T)
4228 and then (Ada_Version < Ada_2005 or else Is_Indefinite_Subtype (T))
4230 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
4234 -- Now we can set the type of the object
4236 Set_Etype (Id, Act_T);
4238 -- Non-constant object is marked to be treated as volatile if type is
4239 -- volatile and we clear the Current_Value setting that may have been
4240 -- set above. Doing so for constants isn't required and might interfere
4241 -- with possible uses of the object as a static expression in contexts
4242 -- incompatible with volatility (e.g. as a case-statement alternative).
4244 if Ekind (Id) /= E_Constant and then Treat_As_Volatile (Etype (Id)) then
4245 Set_Treat_As_Volatile (Id);
4246 Set_Current_Value (Id, Empty);
4249 -- Deal with controlled types
4251 if Has_Controlled_Component (Etype (Id))
4252 or else Is_Controlled (Etype (Id))
4254 if not Is_Library_Level_Entity (Id) then
4255 Check_Restriction (No_Nested_Finalization, N);
4257 Validate_Controlled_Object (Id);
4261 if Has_Task (Etype (Id)) then
4262 Check_Restriction (No_Tasking, N);
4264 -- Deal with counting max tasks
4266 -- Nothing to do if inside a generic
4268 if Inside_A_Generic then
4271 -- If library level entity, then count tasks
4273 elsif Is_Library_Level_Entity (Id) then
4274 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
4276 -- If not library level entity, then indicate we don't know max
4277 -- tasks and also check task hierarchy restriction and blocking
4278 -- operation (since starting a task is definitely blocking).
4281 Check_Restriction (Max_Tasks, N);
4282 Check_Restriction (No_Task_Hierarchy, N);
4283 Check_Potentially_Blocking_Operation (N);
4286 -- A rather specialized test. If we see two tasks being declared
4287 -- of the same type in the same object declaration, and the task
4288 -- has an entry with an address clause, we know that program error
4289 -- will be raised at run time since we can't have two tasks with
4290 -- entries at the same address.
4292 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
4297 E := First_Entity (Etype (Id));
4298 while Present (E) loop
4299 if Ekind (E) = E_Entry
4300 and then Present (Get_Attribute_Definition_Clause
4301 (E, Attribute_Address))
4303 Error_Msg_Warn := SPARK_Mode /= On;
4305 ("more than one task with same entry address<<", N);
4306 Error_Msg_N ("\Program_Error [<<", N);
4308 Make_Raise_Program_Error (Loc,
4309 Reason => PE_Duplicated_Entry_Address));
4319 -- Some simple constant-propagation: if the expression is a constant
4320 -- string initialized with a literal, share the literal. This avoids
4324 and then Is_Entity_Name (E)
4325 and then Ekind (Entity (E)) = E_Constant
4326 and then Base_Type (Etype (E)) = Standard_String
4329 Val : constant Node_Id := Constant_Value (Entity (E));
4331 if Present (Val) and then Nkind (Val) = N_String_Literal then
4332 Rewrite (E, New_Copy (Val));
4337 -- Another optimization: if the nominal subtype is unconstrained and
4338 -- the expression is a function call that returns an unconstrained
4339 -- type, rewrite the declaration as a renaming of the result of the
4340 -- call. The exceptions below are cases where the copy is expected,
4341 -- either by the back end (Aliased case) or by the semantics, as for
4342 -- initializing controlled types or copying tags for classwide types.
4345 and then Nkind (E) = N_Explicit_Dereference
4346 and then Nkind (Original_Node (E)) = N_Function_Call
4347 and then not Is_Library_Level_Entity (Id)
4348 and then not Is_Constrained (Underlying_Type (T))
4349 and then not Is_Aliased (Id)
4350 and then not Is_Class_Wide_Type (T)
4351 and then not Is_Controlled (T)
4352 and then not Has_Controlled_Component (Base_Type (T))
4353 and then Expander_Active
4356 Make_Object_Renaming_Declaration (Loc,
4357 Defining_Identifier => Id,
4358 Access_Definition => Empty,
4359 Subtype_Mark => New_Occurrence_Of
4360 (Base_Type (Etype (Id)), Loc),
4363 Set_Renamed_Object (Id, E);
4365 -- Force generation of debugging information for the constant and for
4366 -- the renamed function call.
4368 Set_Debug_Info_Needed (Id);
4369 Set_Debug_Info_Needed (Entity (Prefix (E)));
4372 if Present (Prev_Entity)
4373 and then Is_Frozen (Prev_Entity)
4374 and then not Error_Posted (Id)
4376 Error_Msg_N ("full constant declaration appears too late", N);
4379 Check_Eliminated (Id);
4381 -- Deal with setting In_Private_Part flag if in private part
4383 if Ekind (Scope (Id)) = E_Package and then In_Private_Part (Scope (Id))
4385 Set_In_Private_Part (Id);
4388 -- Check for violation of No_Local_Timing_Events
4390 if Restriction_Check_Required (No_Local_Timing_Events)
4391 and then not Is_Library_Level_Entity (Id)
4392 and then Is_RTE (Etype (Id), RE_Timing_Event)
4394 Check_Restriction (No_Local_Timing_Events, N);
4398 -- Initialize the refined state of a variable here because this is a
4399 -- common destination for legal and illegal object declarations.
4401 if Ekind (Id) = E_Variable then
4402 Set_Encapsulating_State (Id, Empty);
4405 if Has_Aspects (N) then
4406 Analyze_Aspect_Specifications (N, Id);
4409 Analyze_Dimension (N);
4411 -- Verify whether the object declaration introduces an illegal hidden
4412 -- state within a package subject to a null abstract state.
4414 if Ekind (Id) = E_Variable then
4415 Check_No_Hidden_State (Id);
4417 end Analyze_Object_Declaration;
4419 ---------------------------
4420 -- Analyze_Others_Choice --
4421 ---------------------------
4423 -- Nothing to do for the others choice node itself, the semantic analysis
4424 -- of the others choice will occur as part of the processing of the parent
4426 procedure Analyze_Others_Choice (N : Node_Id) is
4427 pragma Warnings (Off, N);
4430 end Analyze_Others_Choice;
4432 -------------------------------------------
4433 -- Analyze_Private_Extension_Declaration --
4434 -------------------------------------------
4436 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
4437 T : constant Entity_Id := Defining_Identifier (N);
4438 Indic : constant Node_Id := Subtype_Indication (N);
4439 Parent_Type : Entity_Id;
4440 Parent_Base : Entity_Id;
4443 -- The private extension declaration may be subject to pragma Ghost with
4444 -- policy Ignore. Set the mode now to ensure that any nodes generated
4445 -- during analysis and expansion are properly flagged as ignored Ghost.
4449 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
4451 if Is_Non_Empty_List (Interface_List (N)) then
4457 Intf := First (Interface_List (N));
4458 while Present (Intf) loop
4459 T := Find_Type_Of_Subtype_Indic (Intf);
4461 Diagnose_Interface (Intf, T);
4467 Generate_Definition (T);
4469 -- For other than Ada 2012, just enter the name in the current scope
4471 if Ada_Version < Ada_2012 then
4474 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
4475 -- case of private type that completes an incomplete type.
4482 Prev := Find_Type_Name (N);
4484 pragma Assert (Prev = T
4485 or else (Ekind (Prev) = E_Incomplete_Type
4486 and then Present (Full_View (Prev))
4487 and then Full_View (Prev) = T));
4491 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
4492 Parent_Base := Base_Type (Parent_Type);
4494 if Parent_Type = Any_Type or else Etype (Parent_Type) = Any_Type then
4495 Set_Ekind (T, Ekind (Parent_Type));
4496 Set_Etype (T, Any_Type);
4499 elsif not Is_Tagged_Type (Parent_Type) then
4501 ("parent of type extension must be a tagged type ", Indic);
4504 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
4505 Error_Msg_N ("premature derivation of incomplete type", Indic);
4508 elsif Is_Concurrent_Type (Parent_Type) then
4510 ("parent type of a private extension cannot be "
4511 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
4513 Set_Etype (T, Any_Type);
4514 Set_Ekind (T, E_Limited_Private_Type);
4515 Set_Private_Dependents (T, New_Elmt_List);
4516 Set_Error_Posted (T);
4520 -- Perhaps the parent type should be changed to the class-wide type's
4521 -- specific type in this case to prevent cascading errors ???
4523 if Is_Class_Wide_Type (Parent_Type) then
4525 ("parent of type extension must not be a class-wide type", Indic);
4529 if (not Is_Package_Or_Generic_Package (Current_Scope)
4530 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
4531 or else In_Private_Part (Current_Scope)
4534 Error_Msg_N ("invalid context for private extension", N);
4537 -- Set common attributes
4539 Set_Is_Pure (T, Is_Pure (Current_Scope));
4540 Set_Scope (T, Current_Scope);
4541 Set_Ekind (T, E_Record_Type_With_Private);
4542 Init_Size_Align (T);
4543 Set_Default_SSO (T);
4545 Set_Etype (T, Parent_Base);
4546 Set_Has_Task (T, Has_Task (Parent_Base));
4547 Set_Has_Protected (T, Has_Task (Parent_Base));
4549 Set_Convention (T, Convention (Parent_Type));
4550 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
4551 Set_Is_First_Subtype (T);
4552 Make_Class_Wide_Type (T);
4554 if Unknown_Discriminants_Present (N) then
4555 Set_Discriminant_Constraint (T, No_Elist);
4558 Build_Derived_Record_Type (N, Parent_Type, T);
4560 -- Propagate inherited invariant information. The new type has
4561 -- invariants, if the parent type has inheritable invariants,
4562 -- and these invariants can in turn be inherited.
4564 if Has_Inheritable_Invariants (Parent_Type) then
4565 Set_Has_Inheritable_Invariants (T);
4566 Set_Has_Invariants (T);
4569 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
4570 -- synchronized formal derived type.
4572 if Ada_Version >= Ada_2005 and then Synchronized_Present (N) then
4573 Set_Is_Limited_Record (T);
4575 -- Formal derived type case
4577 if Is_Generic_Type (T) then
4579 -- The parent must be a tagged limited type or a synchronized
4582 if (not Is_Tagged_Type (Parent_Type)
4583 or else not Is_Limited_Type (Parent_Type))
4585 (not Is_Interface (Parent_Type)
4586 or else not Is_Synchronized_Interface (Parent_Type))
4588 Error_Msg_NE ("parent type of & must be tagged limited " &
4589 "or synchronized", N, T);
4592 -- The progenitors (if any) must be limited or synchronized
4595 if Present (Interfaces (T)) then
4598 Iface_Elmt : Elmt_Id;
4601 Iface_Elmt := First_Elmt (Interfaces (T));
4602 while Present (Iface_Elmt) loop
4603 Iface := Node (Iface_Elmt);
4605 if not Is_Limited_Interface (Iface)
4606 and then not Is_Synchronized_Interface (Iface)
4608 Error_Msg_NE ("progenitor & must be limited " &
4609 "or synchronized", N, Iface);
4612 Next_Elmt (Iface_Elmt);
4617 -- Regular derived extension, the parent must be a limited or
4618 -- synchronized interface.
4621 if not Is_Interface (Parent_Type)
4622 or else (not Is_Limited_Interface (Parent_Type)
4623 and then not Is_Synchronized_Interface (Parent_Type))
4626 ("parent type of & must be limited interface", N, T);
4630 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
4631 -- extension with a synchronized parent must be explicitly declared
4632 -- synchronized, because the full view will be a synchronized type.
4633 -- This must be checked before the check for limited types below,
4634 -- to ensure that types declared limited are not allowed to extend
4635 -- synchronized interfaces.
4637 elsif Is_Interface (Parent_Type)
4638 and then Is_Synchronized_Interface (Parent_Type)
4639 and then not Synchronized_Present (N)
4642 ("private extension of& must be explicitly synchronized",
4645 elsif Limited_Present (N) then
4646 Set_Is_Limited_Record (T);
4648 if not Is_Limited_Type (Parent_Type)
4650 (not Is_Interface (Parent_Type)
4651 or else not Is_Limited_Interface (Parent_Type))
4653 Error_Msg_NE ("parent type& of limited extension must be limited",
4659 if Has_Aspects (N) then
4660 Analyze_Aspect_Specifications (N, T);
4662 end Analyze_Private_Extension_Declaration;
4664 ---------------------------------
4665 -- Analyze_Subtype_Declaration --
4666 ---------------------------------
4668 procedure Analyze_Subtype_Declaration
4670 Skip : Boolean := False)
4672 Id : constant Entity_Id := Defining_Identifier (N);
4674 R_Checks : Check_Result;
4677 -- The subtype declaration may be subject to pragma Ghost with policy
4678 -- Ignore. Set the mode now to ensure that any nodes generated during
4679 -- analysis and expansion are properly flagged as ignored Ghost.
4683 Generate_Definition (Id);
4684 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4685 Init_Size_Align (Id);
4687 -- The following guard condition on Enter_Name is to handle cases where
4688 -- the defining identifier has already been entered into the scope but
4689 -- the declaration as a whole needs to be analyzed.
4691 -- This case in particular happens for derived enumeration types. The
4692 -- derived enumeration type is processed as an inserted enumeration type
4693 -- declaration followed by a rewritten subtype declaration. The defining
4694 -- identifier, however, is entered into the name scope very early in the
4695 -- processing of the original type declaration and therefore needs to be
4696 -- avoided here, when the created subtype declaration is analyzed. (See
4697 -- Build_Derived_Types)
4699 -- This also happens when the full view of a private type is derived
4700 -- type with constraints. In this case the entity has been introduced
4701 -- in the private declaration.
4703 -- Finally this happens in some complex cases when validity checks are
4704 -- enabled, where the same subtype declaration may be analyzed twice.
4705 -- This can happen if the subtype is created by the pre-analysis of
4706 -- an attribute tht gives the range of a loop statement, and the loop
4707 -- itself appears within an if_statement that will be rewritten during
4711 or else (Present (Etype (Id))
4712 and then (Is_Private_Type (Etype (Id))
4713 or else Is_Task_Type (Etype (Id))
4714 or else Is_Rewrite_Substitution (N)))
4718 elsif Current_Entity (Id) = Id then
4725 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4727 -- Class-wide equivalent types of records with unknown discriminants
4728 -- involve the generation of an itype which serves as the private view
4729 -- of a constrained record subtype. In such cases the base type of the
4730 -- current subtype we are processing is the private itype. Use the full
4731 -- of the private itype when decorating various attributes.
4734 and then Is_Private_Type (T)
4735 and then Present (Full_View (T))
4740 -- Inherit common attributes
4742 Set_Is_Volatile (Id, Is_Volatile (T));
4743 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4744 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4745 Set_Convention (Id, Convention (T));
4747 -- If ancestor has predicates then so does the subtype, and in addition
4748 -- we must delay the freeze to properly arrange predicate inheritance.
4750 -- The Ancestor_Type test is really unpleasant, there seem to be cases
4751 -- in which T = ID, so the above tests and assignments do nothing???
4753 if Has_Predicates (T)
4754 or else (Present (Ancestor_Subtype (T))
4755 and then Has_Predicates (Ancestor_Subtype (T)))
4757 Set_Has_Predicates (Id);
4758 Set_Has_Delayed_Freeze (Id);
4761 -- Subtype of Boolean cannot have a constraint in SPARK
4763 if Is_Boolean_Type (T)
4764 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4766 Check_SPARK_05_Restriction
4767 ("subtype of Boolean cannot have constraint", N);
4770 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4772 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4778 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4779 One_Cstr := First (Constraints (Cstr));
4780 while Present (One_Cstr) loop
4782 -- Index or discriminant constraint in SPARK must be a
4786 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4788 Check_SPARK_05_Restriction
4789 ("subtype mark required", One_Cstr);
4791 -- String subtype must have a lower bound of 1 in SPARK.
4792 -- Note that we do not need to test for the non-static case
4793 -- here, since that was already taken care of in
4794 -- Process_Range_Expr_In_Decl.
4796 elsif Base_Type (T) = Standard_String then
4797 Get_Index_Bounds (One_Cstr, Low, High);
4799 if Is_OK_Static_Expression (Low)
4800 and then Expr_Value (Low) /= 1
4802 Check_SPARK_05_Restriction
4803 ("String subtype must have lower bound of 1", N);
4813 -- In the case where there is no constraint given in the subtype
4814 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4815 -- semantic attributes must be established here.
4817 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
4818 Set_Etype (Id, Base_Type (T));
4820 -- Subtype of unconstrained array without constraint is not allowed
4823 if Is_Array_Type (T) and then not Is_Constrained (T) then
4824 Check_SPARK_05_Restriction
4825 ("subtype of unconstrained array must have constraint", N);
4830 Set_Ekind (Id, E_Array_Subtype);
4831 Copy_Array_Subtype_Attributes (Id, T);
4833 when Decimal_Fixed_Point_Kind =>
4834 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
4835 Set_Digits_Value (Id, Digits_Value (T));
4836 Set_Delta_Value (Id, Delta_Value (T));
4837 Set_Scale_Value (Id, Scale_Value (T));
4838 Set_Small_Value (Id, Small_Value (T));
4839 Set_Scalar_Range (Id, Scalar_Range (T));
4840 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
4841 Set_Is_Constrained (Id, Is_Constrained (T));
4842 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4843 Set_RM_Size (Id, RM_Size (T));
4845 when Enumeration_Kind =>
4846 Set_Ekind (Id, E_Enumeration_Subtype);
4847 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4848 Set_Scalar_Range (Id, Scalar_Range (T));
4849 Set_Is_Character_Type (Id, Is_Character_Type (T));
4850 Set_Is_Constrained (Id, Is_Constrained (T));
4851 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4852 Set_RM_Size (Id, RM_Size (T));
4853 Inherit_Predicate_Flags (Id, T);
4855 when Ordinary_Fixed_Point_Kind =>
4856 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4857 Set_Scalar_Range (Id, Scalar_Range (T));
4858 Set_Small_Value (Id, Small_Value (T));
4859 Set_Delta_Value (Id, Delta_Value (T));
4860 Set_Is_Constrained (Id, Is_Constrained (T));
4861 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4862 Set_RM_Size (Id, RM_Size (T));
4865 Set_Ekind (Id, E_Floating_Point_Subtype);
4866 Set_Scalar_Range (Id, Scalar_Range (T));
4867 Set_Digits_Value (Id, Digits_Value (T));
4868 Set_Is_Constrained (Id, Is_Constrained (T));
4870 when Signed_Integer_Kind =>
4871 Set_Ekind (Id, E_Signed_Integer_Subtype);
4872 Set_Scalar_Range (Id, Scalar_Range (T));
4873 Set_Is_Constrained (Id, Is_Constrained (T));
4874 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4875 Set_RM_Size (Id, RM_Size (T));
4876 Inherit_Predicate_Flags (Id, T);
4878 when Modular_Integer_Kind =>
4879 Set_Ekind (Id, E_Modular_Integer_Subtype);
4880 Set_Scalar_Range (Id, Scalar_Range (T));
4881 Set_Is_Constrained (Id, Is_Constrained (T));
4882 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4883 Set_RM_Size (Id, RM_Size (T));
4884 Inherit_Predicate_Flags (Id, T);
4886 when Class_Wide_Kind =>
4887 Set_Ekind (Id, E_Class_Wide_Subtype);
4888 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4889 Set_Cloned_Subtype (Id, T);
4890 Set_Is_Tagged_Type (Id, True);
4891 Set_Has_Unknown_Discriminants
4893 Set_No_Tagged_Streams_Pragma
4894 (Id, No_Tagged_Streams_Pragma (T));
4896 if Ekind (T) = E_Class_Wide_Subtype then
4897 Set_Equivalent_Type (Id, Equivalent_Type (T));
4900 when E_Record_Type | E_Record_Subtype =>
4901 Set_Ekind (Id, E_Record_Subtype);
4903 if Ekind (T) = E_Record_Subtype
4904 and then Present (Cloned_Subtype (T))
4906 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
4908 Set_Cloned_Subtype (Id, T);
4911 Set_First_Entity (Id, First_Entity (T));
4912 Set_Last_Entity (Id, Last_Entity (T));
4913 Set_Has_Discriminants (Id, Has_Discriminants (T));
4914 Set_Is_Constrained (Id, Is_Constrained (T));
4915 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4916 Set_Has_Implicit_Dereference
4917 (Id, Has_Implicit_Dereference (T));
4918 Set_Has_Unknown_Discriminants
4919 (Id, Has_Unknown_Discriminants (T));
4921 if Has_Discriminants (T) then
4922 Set_Discriminant_Constraint
4923 (Id, Discriminant_Constraint (T));
4924 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4926 elsif Has_Unknown_Discriminants (Id) then
4927 Set_Discriminant_Constraint (Id, No_Elist);
4930 if Is_Tagged_Type (T) then
4931 Set_Is_Tagged_Type (Id, True);
4932 Set_No_Tagged_Streams_Pragma
4933 (Id, No_Tagged_Streams_Pragma (T));
4934 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4935 Set_Direct_Primitive_Operations
4936 (Id, Direct_Primitive_Operations (T));
4937 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4939 if Is_Interface (T) then
4940 Set_Is_Interface (Id);
4941 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
4945 when Private_Kind =>
4946 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4947 Set_Has_Discriminants (Id, Has_Discriminants (T));
4948 Set_Is_Constrained (Id, Is_Constrained (T));
4949 Set_First_Entity (Id, First_Entity (T));
4950 Set_Last_Entity (Id, Last_Entity (T));
4951 Set_Private_Dependents (Id, New_Elmt_List);
4952 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4953 Set_Has_Implicit_Dereference
4954 (Id, Has_Implicit_Dereference (T));
4955 Set_Has_Unknown_Discriminants
4956 (Id, Has_Unknown_Discriminants (T));
4957 Set_Known_To_Have_Preelab_Init
4958 (Id, Known_To_Have_Preelab_Init (T));
4960 if Is_Tagged_Type (T) then
4961 Set_Is_Tagged_Type (Id);
4962 Set_No_Tagged_Streams_Pragma (Id,
4963 No_Tagged_Streams_Pragma (T));
4964 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4965 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4966 Set_Direct_Primitive_Operations (Id,
4967 Direct_Primitive_Operations (T));
4970 -- In general the attributes of the subtype of a private type
4971 -- are the attributes of the partial view of parent. However,
4972 -- the full view may be a discriminated type, and the subtype
4973 -- must share the discriminant constraint to generate correct
4974 -- calls to initialization procedures.
4976 if Has_Discriminants (T) then
4977 Set_Discriminant_Constraint
4978 (Id, Discriminant_Constraint (T));
4979 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4981 elsif Present (Full_View (T))
4982 and then Has_Discriminants (Full_View (T))
4984 Set_Discriminant_Constraint
4985 (Id, Discriminant_Constraint (Full_View (T)));
4986 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4988 -- This would seem semantically correct, but apparently
4989 -- generates spurious errors about missing components ???
4991 -- Set_Has_Discriminants (Id);
4994 Prepare_Private_Subtype_Completion (Id, N);
4996 -- If this is the subtype of a constrained private type with
4997 -- discriminants that has got a full view and we also have
4998 -- built a completion just above, show that the completion
4999 -- is a clone of the full view to the back-end.
5001 if Has_Discriminants (T)
5002 and then not Has_Unknown_Discriminants (T)
5003 and then not Is_Empty_Elmt_List (Discriminant_Constraint (T))
5004 and then Present (Full_View (T))
5005 and then Present (Full_View (Id))
5007 Set_Cloned_Subtype (Full_View (Id), Full_View (T));
5011 Set_Ekind (Id, E_Access_Subtype);
5012 Set_Is_Constrained (Id, Is_Constrained (T));
5013 Set_Is_Access_Constant
5014 (Id, Is_Access_Constant (T));
5015 Set_Directly_Designated_Type
5016 (Id, Designated_Type (T));
5017 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
5019 -- A Pure library_item must not contain the declaration of a
5020 -- named access type, except within a subprogram, generic
5021 -- subprogram, task unit, or protected unit, or if it has
5022 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
5024 if Comes_From_Source (Id)
5025 and then In_Pure_Unit
5026 and then not In_Subprogram_Task_Protected_Unit
5027 and then not No_Pool_Assigned (Id)
5030 ("named access types not allowed in pure unit", N);
5033 when Concurrent_Kind =>
5034 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
5035 Set_Corresponding_Record_Type (Id,
5036 Corresponding_Record_Type (T));
5037 Set_First_Entity (Id, First_Entity (T));
5038 Set_First_Private_Entity (Id, First_Private_Entity (T));
5039 Set_Has_Discriminants (Id, Has_Discriminants (T));
5040 Set_Is_Constrained (Id, Is_Constrained (T));
5041 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5042 Set_Last_Entity (Id, Last_Entity (T));
5044 if Is_Tagged_Type (T) then
5045 Set_No_Tagged_Streams_Pragma
5046 (Id, No_Tagged_Streams_Pragma (T));
5049 if Has_Discriminants (T) then
5050 Set_Discriminant_Constraint
5051 (Id, Discriminant_Constraint (T));
5052 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
5055 when Incomplete_Kind =>
5056 if Ada_Version >= Ada_2005 then
5058 -- In Ada 2005 an incomplete type can be explicitly tagged:
5059 -- propagate indication. Note that we also have to include
5060 -- subtypes for Ada 2012 extended use of incomplete types.
5062 Set_Ekind (Id, E_Incomplete_Subtype);
5063 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
5064 Set_Private_Dependents (Id, New_Elmt_List);
5066 if Is_Tagged_Type (Id) then
5067 Set_No_Tagged_Streams_Pragma
5068 (Id, No_Tagged_Streams_Pragma (T));
5069 Set_Direct_Primitive_Operations (Id, New_Elmt_List);
5072 -- Ada 2005 (AI-412): Decorate an incomplete subtype of an
5073 -- incomplete type visible through a limited with clause.
5075 if From_Limited_With (T)
5076 and then Present (Non_Limited_View (T))
5078 Set_From_Limited_With (Id);
5079 Set_Non_Limited_View (Id, Non_Limited_View (T));
5081 -- Ada 2005 (AI-412): Add the regular incomplete subtype
5082 -- to the private dependents of the original incomplete
5083 -- type for future transformation.
5086 Append_Elmt (Id, Private_Dependents (T));
5089 -- If the subtype name denotes an incomplete type an error
5090 -- was already reported by Process_Subtype.
5093 Set_Etype (Id, Any_Type);
5097 raise Program_Error;
5101 if Etype (Id) = Any_Type then
5105 -- Some common processing on all types
5107 Set_Size_Info (Id, T);
5108 Set_First_Rep_Item (Id, First_Rep_Item (T));
5110 -- If the parent type is a generic actual, so is the subtype. This may
5111 -- happen in a nested instance. Why Comes_From_Source test???
5113 if not Comes_From_Source (N) then
5114 Set_Is_Generic_Actual_Type (Id, Is_Generic_Actual_Type (T));
5119 Set_Is_Immediately_Visible (Id, True);
5120 Set_Depends_On_Private (Id, Has_Private_Component (T));
5121 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
5123 if Is_Interface (T) then
5124 Set_Is_Interface (Id);
5127 if Present (Generic_Parent_Type (N))
5129 (Nkind (Parent (Generic_Parent_Type (N))) /=
5130 N_Formal_Type_Declaration
5131 or else Nkind (Formal_Type_Definition
5132 (Parent (Generic_Parent_Type (N)))) /=
5133 N_Formal_Private_Type_Definition)
5135 if Is_Tagged_Type (Id) then
5137 -- If this is a generic actual subtype for a synchronized type,
5138 -- the primitive operations are those of the corresponding record
5139 -- for which there is a separate subtype declaration.
5141 if Is_Concurrent_Type (Id) then
5143 elsif Is_Class_Wide_Type (Id) then
5144 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
5146 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
5149 elsif Scope (Etype (Id)) /= Standard_Standard then
5150 Derive_Subprograms (Generic_Parent_Type (N), Id);
5154 if Is_Private_Type (T) and then Present (Full_View (T)) then
5155 Conditional_Delay (Id, Full_View (T));
5157 -- The subtypes of components or subcomponents of protected types
5158 -- do not need freeze nodes, which would otherwise appear in the
5159 -- wrong scope (before the freeze node for the protected type). The
5160 -- proper subtypes are those of the subcomponents of the corresponding
5163 elsif Ekind (Scope (Id)) /= E_Protected_Type
5164 and then Present (Scope (Scope (Id))) -- error defense
5165 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
5167 Conditional_Delay (Id, T);
5170 -- Check that Constraint_Error is raised for a scalar subtype indication
5171 -- when the lower or upper bound of a non-null range lies outside the
5172 -- range of the type mark.
5174 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5175 if Is_Scalar_Type (Etype (Id))
5176 and then Scalar_Range (Id) /=
5177 Scalar_Range (Etype (Subtype_Mark
5178 (Subtype_Indication (N))))
5182 Etype (Subtype_Mark (Subtype_Indication (N))));
5184 -- In the array case, check compatibility for each index
5186 elsif Is_Array_Type (Etype (Id)) and then Present (First_Index (Id))
5188 -- This really should be a subprogram that finds the indications
5192 Subt_Index : Node_Id := First_Index (Id);
5193 Target_Index : Node_Id :=
5195 (Subtype_Mark (Subtype_Indication (N))));
5196 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
5199 while Present (Subt_Index) loop
5200 if ((Nkind (Subt_Index) = N_Identifier
5201 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
5202 or else Nkind (Subt_Index) = N_Subtype_Indication)
5204 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
5207 Target_Typ : constant Entity_Id :=
5208 Etype (Target_Index);
5212 (Scalar_Range (Etype (Subt_Index)),
5215 Defining_Identifier (N));
5217 -- Reset Has_Dynamic_Range_Check on the subtype to
5218 -- prevent elision of the index check due to a dynamic
5219 -- check generated for a preceding index (needed since
5220 -- Insert_Range_Checks tries to avoid generating
5221 -- redundant checks on a given declaration).
5223 Set_Has_Dynamic_Range_Check (N, False);
5229 Sloc (Defining_Identifier (N)));
5231 -- Record whether this index involved a dynamic check
5234 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
5238 Next_Index (Subt_Index);
5239 Next_Index (Target_Index);
5242 -- Finally, mark whether the subtype involves dynamic checks
5244 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
5249 -- A type invariant applies to any subtype in its scope, in particular
5250 -- to a generic actual.
5252 if Has_Invariants (T) and then In_Open_Scopes (Scope (T)) then
5253 Set_Has_Invariants (Id);
5254 Set_Invariant_Procedure (Id, Invariant_Procedure (T));
5257 -- Make sure that generic actual types are properly frozen. The subtype
5258 -- is marked as a generic actual type when the enclosing instance is
5259 -- analyzed, so here we identify the subtype from the tree structure.
5262 and then Is_Generic_Actual_Type (Id)
5263 and then In_Instance
5264 and then not Comes_From_Source (N)
5265 and then Nkind (Subtype_Indication (N)) /= N_Subtype_Indication
5266 and then Is_Frozen (T)
5268 Freeze_Before (N, Id);
5271 Set_Optimize_Alignment_Flags (Id);
5272 Check_Eliminated (Id);
5275 if Has_Aspects (N) then
5276 Analyze_Aspect_Specifications (N, Id);
5279 Analyze_Dimension (N);
5280 end Analyze_Subtype_Declaration;
5282 --------------------------------
5283 -- Analyze_Subtype_Indication --
5284 --------------------------------
5286 procedure Analyze_Subtype_Indication (N : Node_Id) is
5287 T : constant Entity_Id := Subtype_Mark (N);
5288 R : constant Node_Id := Range_Expression (Constraint (N));
5295 Set_Etype (N, Etype (R));
5296 Resolve (R, Entity (T));
5298 Set_Error_Posted (R);
5299 Set_Error_Posted (T);
5301 end Analyze_Subtype_Indication;
5303 --------------------------
5304 -- Analyze_Variant_Part --
5305 --------------------------
5307 procedure Analyze_Variant_Part (N : Node_Id) is
5308 Discr_Name : Node_Id;
5309 Discr_Type : Entity_Id;
5311 procedure Process_Variant (A : Node_Id);
5312 -- Analyze declarations for a single variant
5314 package Analyze_Variant_Choices is
5315 new Generic_Analyze_Choices (Process_Variant);
5316 use Analyze_Variant_Choices;
5318 ---------------------
5319 -- Process_Variant --
5320 ---------------------
5322 procedure Process_Variant (A : Node_Id) is
5323 CL : constant Node_Id := Component_List (A);
5325 if not Null_Present (CL) then
5326 Analyze_Declarations (Component_Items (CL));
5328 if Present (Variant_Part (CL)) then
5329 Analyze (Variant_Part (CL));
5332 end Process_Variant;
5334 -- Start of processing for Analyze_Variant_Part
5337 Discr_Name := Name (N);
5338 Analyze (Discr_Name);
5340 -- If Discr_Name bad, get out (prevent cascaded errors)
5342 if Etype (Discr_Name) = Any_Type then
5346 -- Check invalid discriminant in variant part
5348 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
5349 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
5352 Discr_Type := Etype (Entity (Discr_Name));
5354 if not Is_Discrete_Type (Discr_Type) then
5356 ("discriminant in a variant part must be of a discrete type",
5361 -- Now analyze the choices, which also analyzes the declarations that
5362 -- are associated with each choice.
5364 Analyze_Choices (Variants (N), Discr_Type);
5366 -- Note: we used to instantiate and call Check_Choices here to check
5367 -- that the choices covered the discriminant, but it's too early to do
5368 -- that because of statically predicated subtypes, whose analysis may
5369 -- be deferred to their freeze point which may be as late as the freeze
5370 -- point of the containing record. So this call is now to be found in
5371 -- Freeze_Record_Declaration.
5373 end Analyze_Variant_Part;
5375 ----------------------------
5376 -- Array_Type_Declaration --
5377 ----------------------------
5379 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
5380 Component_Def : constant Node_Id := Component_Definition (Def);
5381 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
5382 Element_Type : Entity_Id;
5383 Implicit_Base : Entity_Id;
5385 Related_Id : Entity_Id := Empty;
5387 P : constant Node_Id := Parent (Def);
5391 if Nkind (Def) = N_Constrained_Array_Definition then
5392 Index := First (Discrete_Subtype_Definitions (Def));
5394 Index := First (Subtype_Marks (Def));
5397 -- Find proper names for the implicit types which may be public. In case
5398 -- of anonymous arrays we use the name of the first object of that type
5402 Related_Id := Defining_Identifier (P);
5408 while Present (Index) loop
5411 -- Test for odd case of trying to index a type by the type itself
5413 if Is_Entity_Name (Index) and then Entity (Index) = T then
5414 Error_Msg_N ("type& cannot be indexed by itself", Index);
5415 Set_Entity (Index, Standard_Boolean);
5416 Set_Etype (Index, Standard_Boolean);
5419 -- Check SPARK restriction requiring a subtype mark
5421 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
5422 Check_SPARK_05_Restriction ("subtype mark required", Index);
5425 -- Add a subtype declaration for each index of private array type
5426 -- declaration whose etype is also private. For example:
5429 -- type Index is private;
5431 -- type Table is array (Index) of ...
5434 -- This is currently required by the expander for the internally
5435 -- generated equality subprogram of records with variant parts in
5436 -- which the etype of some component is such private type.
5438 if Ekind (Current_Scope) = E_Package
5439 and then In_Private_Part (Current_Scope)
5440 and then Has_Private_Declaration (Etype (Index))
5443 Loc : constant Source_Ptr := Sloc (Def);
5448 New_E := Make_Temporary (Loc, 'T');
5449 Set_Is_Internal (New_E);
5452 Make_Subtype_Declaration (Loc,
5453 Defining_Identifier => New_E,
5454 Subtype_Indication =>
5455 New_Occurrence_Of (Etype (Index), Loc));
5457 Insert_Before (Parent (Def), Decl);
5459 Set_Etype (Index, New_E);
5461 -- If the index is a range the Entity attribute is not
5462 -- available. Example:
5465 -- type T is private;
5467 -- type T is new Natural;
5468 -- Table : array (T(1) .. T(10)) of Boolean;
5471 if Nkind (Index) /= N_Range then
5472 Set_Entity (Index, New_E);
5477 Make_Index (Index, P, Related_Id, Nb_Index);
5479 -- Check error of subtype with predicate for index type
5481 Bad_Predicated_Subtype_Use
5482 ("subtype& has predicate, not allowed as index subtype",
5483 Index, Etype (Index));
5485 -- Move to next index
5488 Nb_Index := Nb_Index + 1;
5491 -- Process subtype indication if one is present
5493 if Present (Component_Typ) then
5494 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
5496 Set_Etype (Component_Typ, Element_Type);
5498 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
5499 Check_SPARK_05_Restriction
5500 ("subtype mark required", Component_Typ);
5503 -- Ada 2005 (AI-230): Access Definition case
5505 else pragma Assert (Present (Access_Definition (Component_Def)));
5507 -- Indicate that the anonymous access type is created by the
5508 -- array type declaration.
5510 Element_Type := Access_Definition
5512 N => Access_Definition (Component_Def));
5513 Set_Is_Local_Anonymous_Access (Element_Type);
5515 -- Propagate the parent. This field is needed if we have to generate
5516 -- the master_id associated with an anonymous access to task type
5517 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
5519 Set_Parent (Element_Type, Parent (T));
5521 -- Ada 2005 (AI-230): In case of components that are anonymous access
5522 -- types the level of accessibility depends on the enclosing type
5525 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
5527 -- Ada 2005 (AI-254)
5530 CD : constant Node_Id :=
5531 Access_To_Subprogram_Definition
5532 (Access_Definition (Component_Def));
5534 if Present (CD) and then Protected_Present (CD) then
5536 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
5541 -- Constrained array case
5544 T := Create_Itype (E_Void, P, Related_Id, 'T');
5547 if Nkind (Def) = N_Constrained_Array_Definition then
5549 -- Establish Implicit_Base as unconstrained base type
5551 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
5553 Set_Etype (Implicit_Base, Implicit_Base);
5554 Set_Scope (Implicit_Base, Current_Scope);
5555 Set_Has_Delayed_Freeze (Implicit_Base);
5556 Set_Default_SSO (Implicit_Base);
5558 -- The constrained array type is a subtype of the unconstrained one
5560 Set_Ekind (T, E_Array_Subtype);
5561 Init_Size_Align (T);
5562 Set_Etype (T, Implicit_Base);
5563 Set_Scope (T, Current_Scope);
5564 Set_Is_Constrained (T);
5566 First (Discrete_Subtype_Definitions (Def)));
5567 Set_Has_Delayed_Freeze (T);
5569 -- Complete setup of implicit base type
5571 Set_First_Index (Implicit_Base, First_Index (T));
5572 Set_Component_Type (Implicit_Base, Element_Type);
5573 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
5574 Set_Has_Protected (Implicit_Base, Has_Protected (Element_Type));
5575 Set_Component_Size (Implicit_Base, Uint_0);
5576 Set_Packed_Array_Impl_Type (Implicit_Base, Empty);
5577 Set_Has_Controlled_Component (Implicit_Base,
5578 Has_Controlled_Component (Element_Type)
5579 or else Is_Controlled (Element_Type));
5580 Set_Finalize_Storage_Only (Implicit_Base,
5581 Finalize_Storage_Only (Element_Type));
5583 -- Inherit the "ghostness" from the constrained array type
5585 if Is_Ghost_Entity (T) or else Ghost_Mode > None then
5586 Set_Is_Ghost_Entity (Implicit_Base);
5589 -- Unconstrained array case
5592 Set_Ekind (T, E_Array_Type);
5593 Init_Size_Align (T);
5595 Set_Scope (T, Current_Scope);
5596 Set_Component_Size (T, Uint_0);
5597 Set_Is_Constrained (T, False);
5598 Set_First_Index (T, First (Subtype_Marks (Def)));
5599 Set_Has_Delayed_Freeze (T, True);
5600 Set_Has_Task (T, Has_Task (Element_Type));
5601 Set_Has_Protected (T, Has_Protected (Element_Type));
5602 Set_Has_Controlled_Component (T, Has_Controlled_Component
5605 Is_Controlled (Element_Type));
5606 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
5608 Set_Default_SSO (T);
5611 -- Common attributes for both cases
5613 Set_Component_Type (Base_Type (T), Element_Type);
5614 Set_Packed_Array_Impl_Type (T, Empty);
5616 if Aliased_Present (Component_Definition (Def)) then
5617 Check_SPARK_05_Restriction
5618 ("aliased is not allowed", Component_Definition (Def));
5619 Set_Has_Aliased_Components (Etype (T));
5622 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
5623 -- array type to ensure that objects of this type are initialized.
5625 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (Element_Type) then
5626 Set_Can_Never_Be_Null (T);
5628 if Null_Exclusion_Present (Component_Definition (Def))
5630 -- No need to check itypes because in their case this check was
5631 -- done at their point of creation
5633 and then not Is_Itype (Element_Type)
5636 ("`NOT NULL` not allowed (null already excluded)",
5637 Subtype_Indication (Component_Definition (Def)));
5641 Priv := Private_Component (Element_Type);
5643 if Present (Priv) then
5645 -- Check for circular definitions
5647 if Priv = Any_Type then
5648 Set_Component_Type (Etype (T), Any_Type);
5650 -- There is a gap in the visibility of operations on the composite
5651 -- type only if the component type is defined in a different scope.
5653 elsif Scope (Priv) = Current_Scope then
5656 elsif Is_Limited_Type (Priv) then
5657 Set_Is_Limited_Composite (Etype (T));
5658 Set_Is_Limited_Composite (T);
5660 Set_Is_Private_Composite (Etype (T));
5661 Set_Is_Private_Composite (T);
5665 -- A syntax error in the declaration itself may lead to an empty index
5666 -- list, in which case do a minimal patch.
5668 if No (First_Index (T)) then
5669 Error_Msg_N ("missing index definition in array type declaration", T);
5672 Indexes : constant List_Id :=
5673 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
5675 Set_Discrete_Subtype_Definitions (Def, Indexes);
5676 Set_First_Index (T, First (Indexes));
5681 -- Create a concatenation operator for the new type. Internal array
5682 -- types created for packed entities do not need such, they are
5683 -- compatible with the user-defined type.
5685 if Number_Dimensions (T) = 1
5686 and then not Is_Packed_Array_Impl_Type (T)
5688 New_Concatenation_Op (T);
5691 -- In the case of an unconstrained array the parser has already verified
5692 -- that all the indexes are unconstrained but we still need to make sure
5693 -- that the element type is constrained.
5695 if Is_Indefinite_Subtype (Element_Type) then
5697 ("unconstrained element type in array declaration",
5698 Subtype_Indication (Component_Def));
5700 elsif Is_Abstract_Type (Element_Type) then
5702 ("the type of a component cannot be abstract",
5703 Subtype_Indication (Component_Def));
5706 -- There may be an invariant declared for the component type, but
5707 -- the construction of the component invariant checking procedure
5708 -- takes place during expansion.
5709 end Array_Type_Declaration;
5711 ------------------------------------------------------
5712 -- Replace_Anonymous_Access_To_Protected_Subprogram --
5713 ------------------------------------------------------
5715 function Replace_Anonymous_Access_To_Protected_Subprogram
5716 (N : Node_Id) return Entity_Id
5718 Loc : constant Source_Ptr := Sloc (N);
5720 Curr_Scope : constant Scope_Stack_Entry :=
5721 Scope_Stack.Table (Scope_Stack.Last);
5723 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
5726 -- Access definition in declaration
5729 -- Object definition or formal definition with an access definition
5732 -- Declaration of anonymous access to subprogram type
5735 -- Original specification in access to subprogram
5740 Set_Is_Internal (Anon);
5743 when N_Component_Declaration |
5744 N_Unconstrained_Array_Definition |
5745 N_Constrained_Array_Definition =>
5746 Comp := Component_Definition (N);
5747 Acc := Access_Definition (Comp);
5749 when N_Discriminant_Specification =>
5750 Comp := Discriminant_Type (N);
5753 when N_Parameter_Specification =>
5754 Comp := Parameter_Type (N);
5757 when N_Access_Function_Definition =>
5758 Comp := Result_Definition (N);
5761 when N_Object_Declaration =>
5762 Comp := Object_Definition (N);
5765 when N_Function_Specification =>
5766 Comp := Result_Definition (N);
5770 raise Program_Error;
5773 Spec := Access_To_Subprogram_Definition (Acc);
5776 Make_Full_Type_Declaration (Loc,
5777 Defining_Identifier => Anon,
5778 Type_Definition => Copy_Separate_Tree (Spec));
5780 Mark_Rewrite_Insertion (Decl);
5782 -- In ASIS mode, analyze the profile on the original node, because
5783 -- the separate copy does not provide enough links to recover the
5784 -- original tree. Analysis is limited to type annotations, within
5785 -- a temporary scope that serves as an anonymous subprogram to collect
5786 -- otherwise useless temporaries and itypes.
5790 Typ : constant Entity_Id := Make_Temporary (Loc, 'S');
5793 if Nkind (Spec) = N_Access_Function_Definition then
5794 Set_Ekind (Typ, E_Function);
5796 Set_Ekind (Typ, E_Procedure);
5799 Set_Parent (Typ, N);
5800 Set_Scope (Typ, Current_Scope);
5803 Process_Formals (Parameter_Specifications (Spec), Spec);
5805 if Nkind (Spec) = N_Access_Function_Definition then
5807 Def : constant Node_Id := Result_Definition (Spec);
5810 -- The result might itself be an anonymous access type, so
5813 if Nkind (Def) = N_Access_Definition then
5814 if Present (Access_To_Subprogram_Definition (Def)) then
5817 Replace_Anonymous_Access_To_Protected_Subprogram
5820 Find_Type (Subtype_Mark (Def));
5833 -- Insert the new declaration in the nearest enclosing scope. If the
5834 -- node is a body and N is its return type, the declaration belongs in
5835 -- the enclosing scope.
5839 if Nkind (P) = N_Subprogram_Body
5840 and then Nkind (N) = N_Function_Specification
5845 while Present (P) and then not Has_Declarations (P) loop
5849 pragma Assert (Present (P));
5851 if Nkind (P) = N_Package_Specification then
5852 Prepend (Decl, Visible_Declarations (P));
5854 Prepend (Decl, Declarations (P));
5857 -- Replace the anonymous type with an occurrence of the new declaration.
5858 -- In all cases the rewritten node does not have the null-exclusion
5859 -- attribute because (if present) it was already inherited by the
5860 -- anonymous entity (Anon). Thus, in case of components we do not
5861 -- inherit this attribute.
5863 if Nkind (N) = N_Parameter_Specification then
5864 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5865 Set_Etype (Defining_Identifier (N), Anon);
5866 Set_Null_Exclusion_Present (N, False);
5868 elsif Nkind (N) = N_Object_Declaration then
5869 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5870 Set_Etype (Defining_Identifier (N), Anon);
5872 elsif Nkind (N) = N_Access_Function_Definition then
5873 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5875 elsif Nkind (N) = N_Function_Specification then
5876 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5877 Set_Etype (Defining_Unit_Name (N), Anon);
5881 Make_Component_Definition (Loc,
5882 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
5885 Mark_Rewrite_Insertion (Comp);
5887 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition) then
5891 -- Temporarily remove the current scope (record or subprogram) from
5892 -- the stack to add the new declarations to the enclosing scope.
5894 Scope_Stack.Decrement_Last;
5896 Set_Is_Itype (Anon);
5897 Scope_Stack.Append (Curr_Scope);
5900 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
5901 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
5903 end Replace_Anonymous_Access_To_Protected_Subprogram;
5905 -------------------------------
5906 -- Build_Derived_Access_Type --
5907 -------------------------------
5909 procedure Build_Derived_Access_Type
5911 Parent_Type : Entity_Id;
5912 Derived_Type : Entity_Id)
5914 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
5916 Desig_Type : Entity_Id;
5918 Discr_Con_Elist : Elist_Id;
5919 Discr_Con_El : Elmt_Id;
5923 -- Set the designated type so it is available in case this is an access
5924 -- to a self-referential type, e.g. a standard list type with a next
5925 -- pointer. Will be reset after subtype is built.
5927 Set_Directly_Designated_Type
5928 (Derived_Type, Designated_Type (Parent_Type));
5930 Subt := Process_Subtype (S, N);
5932 if Nkind (S) /= N_Subtype_Indication
5933 and then Subt /= Base_Type (Subt)
5935 Set_Ekind (Derived_Type, E_Access_Subtype);
5938 if Ekind (Derived_Type) = E_Access_Subtype then
5940 Pbase : constant Entity_Id := Base_Type (Parent_Type);
5941 Ibase : constant Entity_Id :=
5942 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
5943 Svg_Chars : constant Name_Id := Chars (Ibase);
5944 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
5947 Copy_Node (Pbase, Ibase);
5949 Set_Chars (Ibase, Svg_Chars);
5950 Set_Next_Entity (Ibase, Svg_Next_E);
5951 Set_Sloc (Ibase, Sloc (Derived_Type));
5952 Set_Scope (Ibase, Scope (Derived_Type));
5953 Set_Freeze_Node (Ibase, Empty);
5954 Set_Is_Frozen (Ibase, False);
5955 Set_Comes_From_Source (Ibase, False);
5956 Set_Is_First_Subtype (Ibase, False);
5958 Set_Etype (Ibase, Pbase);
5959 Set_Etype (Derived_Type, Ibase);
5963 Set_Directly_Designated_Type
5964 (Derived_Type, Designated_Type (Subt));
5966 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
5967 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
5968 Set_Size_Info (Derived_Type, Parent_Type);
5969 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
5970 Set_Depends_On_Private (Derived_Type,
5971 Has_Private_Component (Derived_Type));
5972 Conditional_Delay (Derived_Type, Subt);
5974 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
5975 -- that it is not redundant.
5977 if Null_Exclusion_Present (Type_Definition (N)) then
5978 Set_Can_Never_Be_Null (Derived_Type);
5980 -- What is with the "AND THEN FALSE" here ???
5982 if Can_Never_Be_Null (Parent_Type)
5986 ("`NOT NULL` not allowed (& already excludes null)",
5990 elsif Can_Never_Be_Null (Parent_Type) then
5991 Set_Can_Never_Be_Null (Derived_Type);
5994 -- Note: we do not copy the Storage_Size_Variable, since we always go to
5995 -- the root type for this information.
5997 -- Apply range checks to discriminants for derived record case
5998 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
6000 Desig_Type := Designated_Type (Derived_Type);
6001 if Is_Composite_Type (Desig_Type)
6002 and then (not Is_Array_Type (Desig_Type))
6003 and then Has_Discriminants (Desig_Type)
6004 and then Base_Type (Desig_Type) /= Desig_Type
6006 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
6007 Discr_Con_El := First_Elmt (Discr_Con_Elist);
6009 Discr := First_Discriminant (Base_Type (Desig_Type));
6010 while Present (Discr_Con_El) loop
6011 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
6012 Next_Elmt (Discr_Con_El);
6013 Next_Discriminant (Discr);
6016 end Build_Derived_Access_Type;
6018 ------------------------------
6019 -- Build_Derived_Array_Type --
6020 ------------------------------
6022 procedure Build_Derived_Array_Type
6024 Parent_Type : Entity_Id;
6025 Derived_Type : Entity_Id)
6027 Loc : constant Source_Ptr := Sloc (N);
6028 Tdef : constant Node_Id := Type_Definition (N);
6029 Indic : constant Node_Id := Subtype_Indication (Tdef);
6030 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6031 Implicit_Base : Entity_Id;
6032 New_Indic : Node_Id;
6034 procedure Make_Implicit_Base;
6035 -- If the parent subtype is constrained, the derived type is a subtype
6036 -- of an implicit base type derived from the parent base.
6038 ------------------------
6039 -- Make_Implicit_Base --
6040 ------------------------
6042 procedure Make_Implicit_Base is
6045 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6047 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6048 Set_Etype (Implicit_Base, Parent_Base);
6050 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
6051 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
6053 Set_Has_Delayed_Freeze (Implicit_Base, True);
6055 -- Inherit the "ghostness" from the parent base type
6057 if Is_Ghost_Entity (Parent_Base) or else Ghost_Mode > None then
6058 Set_Is_Ghost_Entity (Implicit_Base);
6060 end Make_Implicit_Base;
6062 -- Start of processing for Build_Derived_Array_Type
6065 if not Is_Constrained (Parent_Type) then
6066 if Nkind (Indic) /= N_Subtype_Indication then
6067 Set_Ekind (Derived_Type, E_Array_Type);
6069 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6070 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
6072 Set_Has_Delayed_Freeze (Derived_Type, True);
6076 Set_Etype (Derived_Type, Implicit_Base);
6079 Make_Subtype_Declaration (Loc,
6080 Defining_Identifier => Derived_Type,
6081 Subtype_Indication =>
6082 Make_Subtype_Indication (Loc,
6083 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6084 Constraint => Constraint (Indic)));
6086 Rewrite (N, New_Indic);
6091 if Nkind (Indic) /= N_Subtype_Indication then
6094 Set_Ekind (Derived_Type, Ekind (Parent_Type));
6095 Set_Etype (Derived_Type, Implicit_Base);
6096 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
6099 Error_Msg_N ("illegal constraint on constrained type", Indic);
6103 -- If parent type is not a derived type itself, and is declared in
6104 -- closed scope (e.g. a subprogram), then we must explicitly introduce
6105 -- the new type's concatenation operator since Derive_Subprograms
6106 -- will not inherit the parent's operator. If the parent type is
6107 -- unconstrained, the operator is of the unconstrained base type.
6109 if Number_Dimensions (Parent_Type) = 1
6110 and then not Is_Limited_Type (Parent_Type)
6111 and then not Is_Derived_Type (Parent_Type)
6112 and then not Is_Package_Or_Generic_Package
6113 (Scope (Base_Type (Parent_Type)))
6115 if not Is_Constrained (Parent_Type)
6116 and then Is_Constrained (Derived_Type)
6118 New_Concatenation_Op (Implicit_Base);
6120 New_Concatenation_Op (Derived_Type);
6123 end Build_Derived_Array_Type;
6125 -----------------------------------
6126 -- Build_Derived_Concurrent_Type --
6127 -----------------------------------
6129 procedure Build_Derived_Concurrent_Type
6131 Parent_Type : Entity_Id;
6132 Derived_Type : Entity_Id)
6134 Loc : constant Source_Ptr := Sloc (N);
6136 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
6137 Corr_Decl : Node_Id;
6138 Corr_Decl_Needed : Boolean;
6139 -- If the derived type has fewer discriminants than its parent, the
6140 -- corresponding record is also a derived type, in order to account for
6141 -- the bound discriminants. We create a full type declaration for it in
6144 Constraint_Present : constant Boolean :=
6145 Nkind (Subtype_Indication (Type_Definition (N))) =
6146 N_Subtype_Indication;
6148 D_Constraint : Node_Id;
6149 New_Constraint : Elist_Id;
6150 Old_Disc : Entity_Id;
6151 New_Disc : Entity_Id;
6155 Set_Stored_Constraint (Derived_Type, No_Elist);
6156 Corr_Decl_Needed := False;
6159 if Present (Discriminant_Specifications (N))
6160 and then Constraint_Present
6162 Old_Disc := First_Discriminant (Parent_Type);
6163 New_Disc := First (Discriminant_Specifications (N));
6164 while Present (New_Disc) and then Present (Old_Disc) loop
6165 Next_Discriminant (Old_Disc);
6170 if Present (Old_Disc) and then Expander_Active then
6172 -- The new type has fewer discriminants, so we need to create a new
6173 -- corresponding record, which is derived from the corresponding
6174 -- record of the parent, and has a stored constraint that captures
6175 -- the values of the discriminant constraints. The corresponding
6176 -- record is needed only if expander is active and code generation is
6179 -- The type declaration for the derived corresponding record has the
6180 -- same discriminant part and constraints as the current declaration.
6181 -- Copy the unanalyzed tree to build declaration.
6183 Corr_Decl_Needed := True;
6184 New_N := Copy_Separate_Tree (N);
6187 Make_Full_Type_Declaration (Loc,
6188 Defining_Identifier => Corr_Record,
6189 Discriminant_Specifications =>
6190 Discriminant_Specifications (New_N),
6192 Make_Derived_Type_Definition (Loc,
6193 Subtype_Indication =>
6194 Make_Subtype_Indication (Loc,
6197 (Corresponding_Record_Type (Parent_Type), Loc),
6200 (Subtype_Indication (Type_Definition (New_N))))));
6203 -- Copy Storage_Size and Relative_Deadline variables if task case
6205 if Is_Task_Type (Parent_Type) then
6206 Set_Storage_Size_Variable (Derived_Type,
6207 Storage_Size_Variable (Parent_Type));
6208 Set_Relative_Deadline_Variable (Derived_Type,
6209 Relative_Deadline_Variable (Parent_Type));
6212 if Present (Discriminant_Specifications (N)) then
6213 Push_Scope (Derived_Type);
6214 Check_Or_Process_Discriminants (N, Derived_Type);
6216 if Constraint_Present then
6218 Expand_To_Stored_Constraint
6220 Build_Discriminant_Constraints
6222 Subtype_Indication (Type_Definition (N)), True));
6227 elsif Constraint_Present then
6229 -- Build constrained subtype, copying the constraint, and derive
6230 -- from it to create a derived constrained type.
6233 Loc : constant Source_Ptr := Sloc (N);
6234 Anon : constant Entity_Id :=
6235 Make_Defining_Identifier (Loc,
6236 Chars => New_External_Name (Chars (Derived_Type), 'T'));
6241 Make_Subtype_Declaration (Loc,
6242 Defining_Identifier => Anon,
6243 Subtype_Indication =>
6244 New_Copy_Tree (Subtype_Indication (Type_Definition (N))));
6245 Insert_Before (N, Decl);
6248 Rewrite (Subtype_Indication (Type_Definition (N)),
6249 New_Occurrence_Of (Anon, Loc));
6250 Set_Analyzed (Derived_Type, False);
6256 -- By default, operations and private data are inherited from parent.
6257 -- However, in the presence of bound discriminants, a new corresponding
6258 -- record will be created, see below.
6260 Set_Has_Discriminants
6261 (Derived_Type, Has_Discriminants (Parent_Type));
6262 Set_Corresponding_Record_Type
6263 (Derived_Type, Corresponding_Record_Type (Parent_Type));
6265 -- Is_Constrained is set according the parent subtype, but is set to
6266 -- False if the derived type is declared with new discriminants.
6270 (Is_Constrained (Parent_Type) or else Constraint_Present)
6271 and then not Present (Discriminant_Specifications (N)));
6273 if Constraint_Present then
6274 if not Has_Discriminants (Parent_Type) then
6275 Error_Msg_N ("untagged parent must have discriminants", N);
6277 elsif Present (Discriminant_Specifications (N)) then
6279 -- Verify that new discriminants are used to constrain old ones
6284 (Constraint (Subtype_Indication (Type_Definition (N)))));
6286 Old_Disc := First_Discriminant (Parent_Type);
6288 while Present (D_Constraint) loop
6289 if Nkind (D_Constraint) /= N_Discriminant_Association then
6291 -- Positional constraint. If it is a reference to a new
6292 -- discriminant, it constrains the corresponding old one.
6294 if Nkind (D_Constraint) = N_Identifier then
6295 New_Disc := First_Discriminant (Derived_Type);
6296 while Present (New_Disc) loop
6297 exit when Chars (New_Disc) = Chars (D_Constraint);
6298 Next_Discriminant (New_Disc);
6301 if Present (New_Disc) then
6302 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
6306 Next_Discriminant (Old_Disc);
6308 -- if this is a named constraint, search by name for the old
6309 -- discriminants constrained by the new one.
6311 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
6313 -- Find new discriminant with that name
6315 New_Disc := First_Discriminant (Derived_Type);
6316 while Present (New_Disc) loop
6318 Chars (New_Disc) = Chars (Expression (D_Constraint));
6319 Next_Discriminant (New_Disc);
6322 if Present (New_Disc) then
6324 -- Verify that new discriminant renames some discriminant
6325 -- of the parent type, and associate the new discriminant
6326 -- with one or more old ones that it renames.
6332 Selector := First (Selector_Names (D_Constraint));
6333 while Present (Selector) loop
6334 Old_Disc := First_Discriminant (Parent_Type);
6335 while Present (Old_Disc) loop
6336 exit when Chars (Old_Disc) = Chars (Selector);
6337 Next_Discriminant (Old_Disc);
6340 if Present (Old_Disc) then
6341 Set_Corresponding_Discriminant
6342 (New_Disc, Old_Disc);
6351 Next (D_Constraint);
6354 New_Disc := First_Discriminant (Derived_Type);
6355 while Present (New_Disc) loop
6356 if No (Corresponding_Discriminant (New_Disc)) then
6358 ("new discriminant& must constrain old one", N, New_Disc);
6361 Subtypes_Statically_Compatible
6363 Etype (Corresponding_Discriminant (New_Disc)))
6366 ("& not statically compatible with parent discriminant",
6370 Next_Discriminant (New_Disc);
6374 elsif Present (Discriminant_Specifications (N)) then
6376 ("missing discriminant constraint in untagged derivation", N);
6379 -- The entity chain of the derived type includes the new discriminants
6380 -- but shares operations with the parent.
6382 if Present (Discriminant_Specifications (N)) then
6383 Old_Disc := First_Discriminant (Parent_Type);
6384 while Present (Old_Disc) loop
6385 if No (Next_Entity (Old_Disc))
6386 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
6389 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
6393 Next_Discriminant (Old_Disc);
6397 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
6398 if Has_Discriminants (Parent_Type) then
6399 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6400 Set_Discriminant_Constraint (
6401 Derived_Type, Discriminant_Constraint (Parent_Type));
6405 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
6407 Set_Has_Completion (Derived_Type);
6409 if Corr_Decl_Needed then
6410 Set_Stored_Constraint (Derived_Type, New_Constraint);
6411 Insert_After (N, Corr_Decl);
6412 Analyze (Corr_Decl);
6413 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
6415 end Build_Derived_Concurrent_Type;
6417 ------------------------------------
6418 -- Build_Derived_Enumeration_Type --
6419 ------------------------------------
6421 procedure Build_Derived_Enumeration_Type
6423 Parent_Type : Entity_Id;
6424 Derived_Type : Entity_Id)
6426 Loc : constant Source_Ptr := Sloc (N);
6427 Def : constant Node_Id := Type_Definition (N);
6428 Indic : constant Node_Id := Subtype_Indication (Def);
6429 Implicit_Base : Entity_Id;
6430 Literal : Entity_Id;
6431 New_Lit : Entity_Id;
6432 Literals_List : List_Id;
6433 Type_Decl : Node_Id;
6435 Rang_Expr : Node_Id;
6438 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
6439 -- not have explicit literals lists we need to process types derived
6440 -- from them specially. This is handled by Derived_Standard_Character.
6441 -- If the parent type is a generic type, there are no literals either,
6442 -- and we construct the same skeletal representation as for the generic
6445 if Is_Standard_Character_Type (Parent_Type) then
6446 Derived_Standard_Character (N, Parent_Type, Derived_Type);
6448 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
6454 if Nkind (Indic) /= N_Subtype_Indication then
6456 Make_Attribute_Reference (Loc,
6457 Attribute_Name => Name_First,
6458 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6459 Set_Etype (Lo, Derived_Type);
6462 Make_Attribute_Reference (Loc,
6463 Attribute_Name => Name_Last,
6464 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6465 Set_Etype (Hi, Derived_Type);
6467 Set_Scalar_Range (Derived_Type,
6473 -- Analyze subtype indication and verify compatibility
6474 -- with parent type.
6476 if Base_Type (Process_Subtype (Indic, N)) /=
6477 Base_Type (Parent_Type)
6480 ("illegal constraint for formal discrete type", N);
6486 -- If a constraint is present, analyze the bounds to catch
6487 -- premature usage of the derived literals.
6489 if Nkind (Indic) = N_Subtype_Indication
6490 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
6492 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
6493 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
6496 -- Introduce an implicit base type for the derived type even if there
6497 -- is no constraint attached to it, since this seems closer to the
6498 -- Ada semantics. Build a full type declaration tree for the derived
6499 -- type using the implicit base type as the defining identifier. The
6500 -- build a subtype declaration tree which applies the constraint (if
6501 -- any) have it replace the derived type declaration.
6503 Literal := First_Literal (Parent_Type);
6504 Literals_List := New_List;
6505 while Present (Literal)
6506 and then Ekind (Literal) = E_Enumeration_Literal
6508 -- Literals of the derived type have the same representation as
6509 -- those of the parent type, but this representation can be
6510 -- overridden by an explicit representation clause. Indicate
6511 -- that there is no explicit representation given yet. These
6512 -- derived literals are implicit operations of the new type,
6513 -- and can be overridden by explicit ones.
6515 if Nkind (Literal) = N_Defining_Character_Literal then
6517 Make_Defining_Character_Literal (Loc, Chars (Literal));
6519 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
6522 Set_Ekind (New_Lit, E_Enumeration_Literal);
6523 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
6524 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
6525 Set_Enumeration_Rep_Expr (New_Lit, Empty);
6526 Set_Alias (New_Lit, Literal);
6527 Set_Is_Known_Valid (New_Lit, True);
6529 Append (New_Lit, Literals_List);
6530 Next_Literal (Literal);
6534 Make_Defining_Identifier (Sloc (Derived_Type),
6535 Chars => New_External_Name (Chars (Derived_Type), 'B'));
6537 -- Indicate the proper nature of the derived type. This must be done
6538 -- before analysis of the literals, to recognize cases when a literal
6539 -- may be hidden by a previous explicit function definition (cf.
6542 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
6543 Set_Etype (Derived_Type, Implicit_Base);
6546 Make_Full_Type_Declaration (Loc,
6547 Defining_Identifier => Implicit_Base,
6548 Discriminant_Specifications => No_List,
6550 Make_Enumeration_Type_Definition (Loc, Literals_List));
6552 Mark_Rewrite_Insertion (Type_Decl);
6553 Insert_Before (N, Type_Decl);
6554 Analyze (Type_Decl);
6556 -- After the implicit base is analyzed its Etype needs to be changed
6557 -- to reflect the fact that it is derived from the parent type which
6558 -- was ignored during analysis. We also set the size at this point.
6560 Set_Etype (Implicit_Base, Parent_Type);
6562 Set_Size_Info (Implicit_Base, Parent_Type);
6563 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
6564 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
6566 -- Copy other flags from parent type
6568 Set_Has_Non_Standard_Rep
6569 (Implicit_Base, Has_Non_Standard_Rep
6571 Set_Has_Pragma_Ordered
6572 (Implicit_Base, Has_Pragma_Ordered
6574 Set_Has_Delayed_Freeze (Implicit_Base);
6576 -- Process the subtype indication including a validation check on the
6577 -- constraint, if any. If a constraint is given, its bounds must be
6578 -- implicitly converted to the new type.
6580 if Nkind (Indic) = N_Subtype_Indication then
6582 R : constant Node_Id :=
6583 Range_Expression (Constraint (Indic));
6586 if Nkind (R) = N_Range then
6587 Hi := Build_Scalar_Bound
6588 (High_Bound (R), Parent_Type, Implicit_Base);
6589 Lo := Build_Scalar_Bound
6590 (Low_Bound (R), Parent_Type, Implicit_Base);
6593 -- Constraint is a Range attribute. Replace with explicit
6594 -- mention of the bounds of the prefix, which must be a
6597 Analyze (Prefix (R));
6599 Convert_To (Implicit_Base,
6600 Make_Attribute_Reference (Loc,
6601 Attribute_Name => Name_Last,
6603 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6606 Convert_To (Implicit_Base,
6607 Make_Attribute_Reference (Loc,
6608 Attribute_Name => Name_First,
6610 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6617 (Type_High_Bound (Parent_Type),
6618 Parent_Type, Implicit_Base);
6621 (Type_Low_Bound (Parent_Type),
6622 Parent_Type, Implicit_Base);
6630 -- If we constructed a default range for the case where no range
6631 -- was given, then the expressions in the range must not freeze
6632 -- since they do not correspond to expressions in the source.
6634 if Nkind (Indic) /= N_Subtype_Indication then
6635 Set_Must_Not_Freeze (Lo);
6636 Set_Must_Not_Freeze (Hi);
6637 Set_Must_Not_Freeze (Rang_Expr);
6641 Make_Subtype_Declaration (Loc,
6642 Defining_Identifier => Derived_Type,
6643 Subtype_Indication =>
6644 Make_Subtype_Indication (Loc,
6645 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6647 Make_Range_Constraint (Loc,
6648 Range_Expression => Rang_Expr))));
6652 -- Propagate the aspects from the original type declaration to the
6653 -- declaration of the implicit base.
6655 Move_Aspects (From => Original_Node (N), To => Type_Decl);
6657 -- Apply a range check. Since this range expression doesn't have an
6658 -- Etype, we have to specifically pass the Source_Typ parameter. Is
6661 if Nkind (Indic) = N_Subtype_Indication then
6663 (Range_Expression (Constraint (Indic)), Parent_Type,
6664 Source_Typ => Entity (Subtype_Mark (Indic)));
6667 end Build_Derived_Enumeration_Type;
6669 --------------------------------
6670 -- Build_Derived_Numeric_Type --
6671 --------------------------------
6673 procedure Build_Derived_Numeric_Type
6675 Parent_Type : Entity_Id;
6676 Derived_Type : Entity_Id)
6678 Loc : constant Source_Ptr := Sloc (N);
6679 Tdef : constant Node_Id := Type_Definition (N);
6680 Indic : constant Node_Id := Subtype_Indication (Tdef);
6681 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6682 No_Constraint : constant Boolean := Nkind (Indic) /=
6683 N_Subtype_Indication;
6684 Implicit_Base : Entity_Id;
6690 -- Process the subtype indication including a validation check on
6691 -- the constraint if any.
6693 Discard_Node (Process_Subtype (Indic, N));
6695 -- Introduce an implicit base type for the derived type even if there
6696 -- is no constraint attached to it, since this seems closer to the Ada
6700 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6702 Set_Etype (Implicit_Base, Parent_Base);
6703 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6704 Set_Size_Info (Implicit_Base, Parent_Base);
6705 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
6706 Set_Parent (Implicit_Base, Parent (Derived_Type));
6707 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
6709 -- Set RM Size for discrete type or decimal fixed-point type
6710 -- Ordinary fixed-point is excluded, why???
6712 if Is_Discrete_Type (Parent_Base)
6713 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
6715 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
6718 Set_Has_Delayed_Freeze (Implicit_Base);
6720 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
6721 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
6723 Set_Scalar_Range (Implicit_Base,
6728 if Has_Infinities (Parent_Base) then
6729 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
6732 -- The Derived_Type, which is the entity of the declaration, is a
6733 -- subtype of the implicit base. Its Ekind is a subtype, even in the
6734 -- absence of an explicit constraint.
6736 Set_Etype (Derived_Type, Implicit_Base);
6738 -- If we did not have a constraint, then the Ekind is set from the
6739 -- parent type (otherwise Process_Subtype has set the bounds)
6741 if No_Constraint then
6742 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
6745 -- If we did not have a range constraint, then set the range from the
6746 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
6748 if No_Constraint or else not Has_Range_Constraint (Indic) then
6749 Set_Scalar_Range (Derived_Type,
6751 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
6752 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
6753 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6755 if Has_Infinities (Parent_Type) then
6756 Set_Includes_Infinities (Scalar_Range (Derived_Type));
6759 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
6762 Set_Is_Descendent_Of_Address (Derived_Type,
6763 Is_Descendent_Of_Address (Parent_Type));
6764 Set_Is_Descendent_Of_Address (Implicit_Base,
6765 Is_Descendent_Of_Address (Parent_Type));
6767 -- Set remaining type-specific fields, depending on numeric type
6769 if Is_Modular_Integer_Type (Parent_Type) then
6770 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
6772 Set_Non_Binary_Modulus
6773 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
6776 (Implicit_Base, Is_Known_Valid (Parent_Base));
6778 elsif Is_Floating_Point_Type (Parent_Type) then
6780 -- Digits of base type is always copied from the digits value of
6781 -- the parent base type, but the digits of the derived type will
6782 -- already have been set if there was a constraint present.
6784 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6785 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
6787 if No_Constraint then
6788 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
6791 elsif Is_Fixed_Point_Type (Parent_Type) then
6793 -- Small of base type and derived type are always copied from the
6794 -- parent base type, since smalls never change. The delta of the
6795 -- base type is also copied from the parent base type. However the
6796 -- delta of the derived type will have been set already if a
6797 -- constraint was present.
6799 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
6800 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
6801 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
6803 if No_Constraint then
6804 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
6807 -- The scale and machine radix in the decimal case are always
6808 -- copied from the parent base type.
6810 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
6811 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
6812 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
6814 Set_Machine_Radix_10
6815 (Derived_Type, Machine_Radix_10 (Parent_Base));
6816 Set_Machine_Radix_10
6817 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6819 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6821 if No_Constraint then
6822 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6825 -- the analysis of the subtype_indication sets the
6826 -- digits value of the derived type.
6833 if Is_Integer_Type (Parent_Type) then
6834 Set_Has_Shift_Operator
6835 (Implicit_Base, Has_Shift_Operator (Parent_Type));
6838 -- The type of the bounds is that of the parent type, and they
6839 -- must be converted to the derived type.
6841 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
6843 -- The implicit_base should be frozen when the derived type is frozen,
6844 -- but note that it is used in the conversions of the bounds. For fixed
6845 -- types we delay the determination of the bounds until the proper
6846 -- freezing point. For other numeric types this is rejected by GCC, for
6847 -- reasons that are currently unclear (???), so we choose to freeze the
6848 -- implicit base now. In the case of integers and floating point types
6849 -- this is harmless because subsequent representation clauses cannot
6850 -- affect anything, but it is still baffling that we cannot use the
6851 -- same mechanism for all derived numeric types.
6853 -- There is a further complication: actually some representation
6854 -- clauses can affect the implicit base type. For example, attribute
6855 -- definition clauses for stream-oriented attributes need to set the
6856 -- corresponding TSS entries on the base type, and this normally
6857 -- cannot be done after the base type is frozen, so the circuitry in
6858 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility
6859 -- and not use Set_TSS in this case.
6861 -- There are also consequences for the case of delayed representation
6862 -- aspects for some cases. For example, a Size aspect is delayed and
6863 -- should not be evaluated to the freeze point. This early freezing
6864 -- means that the size attribute evaluation happens too early???
6866 if Is_Fixed_Point_Type (Parent_Type) then
6867 Conditional_Delay (Implicit_Base, Parent_Type);
6869 Freeze_Before (N, Implicit_Base);
6871 end Build_Derived_Numeric_Type;
6873 --------------------------------
6874 -- Build_Derived_Private_Type --
6875 --------------------------------
6877 procedure Build_Derived_Private_Type
6879 Parent_Type : Entity_Id;
6880 Derived_Type : Entity_Id;
6881 Is_Completion : Boolean;
6882 Derive_Subps : Boolean := True)
6884 Loc : constant Source_Ptr := Sloc (N);
6885 Par_Base : constant Entity_Id := Base_Type (Parent_Type);
6886 Par_Scope : constant Entity_Id := Scope (Par_Base);
6887 Full_N : constant Node_Id := New_Copy_Tree (N);
6888 Full_Der : Entity_Id := New_Copy (Derived_Type);
6891 procedure Build_Full_Derivation;
6892 -- Build full derivation, i.e. derive from the full view
6894 procedure Copy_And_Build;
6895 -- Copy derived type declaration, replace parent with its full view,
6896 -- and build derivation
6898 ---------------------------
6899 -- Build_Full_Derivation --
6900 ---------------------------
6902 procedure Build_Full_Derivation is
6904 -- If parent scope is not open, install the declarations
6906 if not In_Open_Scopes (Par_Scope) then
6907 Install_Private_Declarations (Par_Scope);
6908 Install_Visible_Declarations (Par_Scope);
6910 Uninstall_Declarations (Par_Scope);
6912 -- If parent scope is open and in another unit, and parent has a
6913 -- completion, then the derivation is taking place in the visible
6914 -- part of a child unit. In that case retrieve the full view of
6915 -- the parent momentarily.
6917 elsif not In_Same_Source_Unit (N, Parent_Type) then
6918 Full_P := Full_View (Parent_Type);
6919 Exchange_Declarations (Parent_Type);
6921 Exchange_Declarations (Full_P);
6923 -- Otherwise it is a local derivation
6928 end Build_Full_Derivation;
6930 --------------------
6931 -- Copy_And_Build --
6932 --------------------
6934 procedure Copy_And_Build is
6935 Full_Parent : Entity_Id := Parent_Type;
6938 -- If the parent is itself derived from another private type,
6939 -- installing the private declarations has not affected its
6940 -- privacy status, so use its own full view explicitly.
6942 if Is_Private_Type (Full_Parent)
6943 and then Present (Full_View (Full_Parent))
6945 Full_Parent := Full_View (Full_Parent);
6948 -- And its underlying full view if necessary
6950 if Is_Private_Type (Full_Parent)
6951 and then Present (Underlying_Full_View (Full_Parent))
6953 Full_Parent := Underlying_Full_View (Full_Parent);
6956 -- For record, access and most enumeration types, derivation from
6957 -- the full view requires a fully-fledged declaration. In the other
6958 -- cases, just use an itype.
6960 if Ekind (Full_Parent) in Record_Kind
6961 or else Ekind (Full_Parent) in Access_Kind
6963 (Ekind (Full_Parent) in Enumeration_Kind
6964 and then not Is_Standard_Character_Type (Full_Parent)
6965 and then not Is_Generic_Type (Root_Type (Full_Parent)))
6967 -- Copy and adjust declaration to provide a completion for what
6968 -- is originally a private declaration. Indicate that full view
6969 -- is internally generated.
6971 Set_Comes_From_Source (Full_N, False);
6972 Set_Comes_From_Source (Full_Der, False);
6973 Set_Parent (Full_Der, Full_N);
6974 Set_Defining_Identifier (Full_N, Full_Der);
6976 -- If there are no constraints, adjust the subtype mark
6978 if Nkind (Subtype_Indication (Type_Definition (Full_N))) /=
6979 N_Subtype_Indication
6981 Set_Subtype_Indication
6982 (Type_Definition (Full_N),
6983 New_Occurrence_Of (Full_Parent, Sloc (Full_N)));
6986 Insert_After (N, Full_N);
6988 -- Build full view of derived type from full view of parent which
6989 -- is now installed. Subprograms have been derived on the partial
6990 -- view, the completion does not derive them anew.
6992 if Ekind (Full_Parent) in Record_Kind then
6994 -- If parent type is tagged, the completion inherits the proper
6995 -- primitive operations.
6997 if Is_Tagged_Type (Parent_Type) then
6998 Build_Derived_Record_Type
6999 (Full_N, Full_Parent, Full_Der, Derive_Subps);
7001 Build_Derived_Record_Type
7002 (Full_N, Full_Parent, Full_Der, Derive_Subps => False);
7007 (Full_N, Full_Parent, Full_Der,
7008 Is_Completion => False, Derive_Subps => False);
7011 -- The full declaration has been introduced into the tree and
7012 -- processed in the step above. It should not be analyzed again
7013 -- (when encountered later in the current list of declarations)
7014 -- to prevent spurious name conflicts. The full entity remains
7017 Set_Analyzed (Full_N);
7021 Make_Defining_Identifier (Sloc (Derived_Type),
7022 Chars => Chars (Derived_Type));
7023 Set_Is_Itype (Full_Der);
7024 Set_Associated_Node_For_Itype (Full_Der, N);
7025 Set_Parent (Full_Der, N);
7027 (N, Full_Parent, Full_Der,
7028 Is_Completion => False, Derive_Subps => False);
7031 Set_Has_Private_Declaration (Full_Der);
7032 Set_Has_Private_Declaration (Derived_Type);
7034 Set_Scope (Full_Der, Scope (Derived_Type));
7035 Set_Is_First_Subtype (Full_Der, Is_First_Subtype (Derived_Type));
7036 Set_Has_Size_Clause (Full_Der, False);
7037 Set_Has_Alignment_Clause (Full_Der, False);
7038 Set_Has_Delayed_Freeze (Full_Der);
7039 Set_Is_Frozen (Full_Der, False);
7040 Set_Freeze_Node (Full_Der, Empty);
7041 Set_Depends_On_Private (Full_Der, Has_Private_Component (Full_Der));
7042 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
7044 -- The convention on the base type may be set in the private part
7045 -- and not propagated to the subtype until later, so we obtain the
7046 -- convention from the base type of the parent.
7048 Set_Convention (Full_Der, Convention (Base_Type (Full_Parent)));
7051 -- Start of processing for Build_Derived_Private_Type
7054 if Is_Tagged_Type (Parent_Type) then
7055 Full_P := Full_View (Parent_Type);
7057 -- A type extension of a type with unknown discriminants is an
7058 -- indefinite type that the back-end cannot handle directly.
7059 -- We treat it as a private type, and build a completion that is
7060 -- derived from the full view of the parent, and hopefully has
7061 -- known discriminants.
7063 -- If the full view of the parent type has an underlying record view,
7064 -- use it to generate the underlying record view of this derived type
7065 -- (required for chains of derivations with unknown discriminants).
7067 -- Minor optimization: we avoid the generation of useless underlying
7068 -- record view entities if the private type declaration has unknown
7069 -- discriminants but its corresponding full view has no
7072 if Has_Unknown_Discriminants (Parent_Type)
7073 and then Present (Full_P)
7074 and then (Has_Discriminants (Full_P)
7075 or else Present (Underlying_Record_View (Full_P)))
7076 and then not In_Open_Scopes (Par_Scope)
7077 and then Expander_Active
7080 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
7081 New_Ext : constant Node_Id :=
7083 (Record_Extension_Part (Type_Definition (N)));
7087 Build_Derived_Record_Type
7088 (N, Parent_Type, Derived_Type, Derive_Subps);
7090 -- Build anonymous completion, as a derivation from the full
7091 -- view of the parent. This is not a completion in the usual
7092 -- sense, because the current type is not private.
7095 Make_Full_Type_Declaration (Loc,
7096 Defining_Identifier => Full_Der,
7098 Make_Derived_Type_Definition (Loc,
7099 Subtype_Indication =>
7101 (Subtype_Indication (Type_Definition (N))),
7102 Record_Extension_Part => New_Ext));
7104 -- If the parent type has an underlying record view, use it
7105 -- here to build the new underlying record view.
7107 if Present (Underlying_Record_View (Full_P)) then
7109 (Nkind (Subtype_Indication (Type_Definition (Decl)))
7111 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
7112 Underlying_Record_View (Full_P));
7115 Install_Private_Declarations (Par_Scope);
7116 Install_Visible_Declarations (Par_Scope);
7117 Insert_Before (N, Decl);
7119 -- Mark entity as an underlying record view before analysis,
7120 -- to avoid generating the list of its primitive operations
7121 -- (which is not really required for this entity) and thus
7122 -- prevent spurious errors associated with missing overriding
7123 -- of abstract primitives (overridden only for Derived_Type).
7125 Set_Ekind (Full_Der, E_Record_Type);
7126 Set_Is_Underlying_Record_View (Full_Der);
7127 Set_Default_SSO (Full_Der);
7131 pragma Assert (Has_Discriminants (Full_Der)
7132 and then not Has_Unknown_Discriminants (Full_Der));
7134 Uninstall_Declarations (Par_Scope);
7136 -- Freeze the underlying record view, to prevent generation of
7137 -- useless dispatching information, which is simply shared with
7138 -- the real derived type.
7140 Set_Is_Frozen (Full_Der);
7142 -- If the derived type has access discriminants, create
7143 -- references to their anonymous types now, to prevent
7144 -- back-end problems when their first use is in generated
7145 -- bodies of primitives.
7151 E := First_Entity (Full_Der);
7153 while Present (E) loop
7154 if Ekind (E) = E_Discriminant
7155 and then Ekind (Etype (E)) = E_Anonymous_Access_Type
7157 Build_Itype_Reference (Etype (E), Decl);
7164 -- Set up links between real entity and underlying record view
7166 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
7167 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
7170 -- If discriminants are known, build derived record
7173 Build_Derived_Record_Type
7174 (N, Parent_Type, Derived_Type, Derive_Subps);
7179 elsif Has_Discriminants (Parent_Type) then
7181 -- Build partial view of derived type from partial view of parent.
7182 -- This must be done before building the full derivation because the
7183 -- second derivation will modify the discriminants of the first and
7184 -- the discriminants are chained with the rest of the components in
7185 -- the full derivation.
7187 Build_Derived_Record_Type
7188 (N, Parent_Type, Derived_Type, Derive_Subps);
7190 -- Build the full derivation if this is not the anonymous derived
7191 -- base type created by Build_Derived_Record_Type in the constrained
7192 -- case (see point 5. of its head comment) since we build it for the
7193 -- derived subtype. And skip it for protected types altogether, as
7194 -- gigi does not use these types directly.
7196 if Present (Full_View (Parent_Type))
7197 and then not Is_Itype (Derived_Type)
7198 and then not (Ekind (Full_View (Parent_Type)) in Protected_Kind)
7201 Der_Base : constant Entity_Id := Base_Type (Derived_Type);
7203 Last_Discr : Entity_Id;
7206 -- If this is not a completion, construct the implicit full
7207 -- view by deriving from the full view of the parent type.
7208 -- But if this is a completion, the derived private type
7209 -- being built is a full view and the full derivation can
7210 -- only be its underlying full view.
7212 Build_Full_Derivation;
7214 if not Is_Completion then
7215 Set_Full_View (Derived_Type, Full_Der);
7217 Set_Underlying_Full_View (Derived_Type, Full_Der);
7220 if not Is_Base_Type (Derived_Type) then
7221 Set_Full_View (Der_Base, Base_Type (Full_Der));
7224 -- Copy the discriminant list from full view to the partial
7225 -- view (base type and its subtype). Gigi requires that the
7226 -- partial and full views have the same discriminants.
7228 -- Note that since the partial view points to discriminants
7229 -- in the full view, their scope will be that of the full
7230 -- view. This might cause some front end problems and need
7233 Discr := First_Discriminant (Base_Type (Full_Der));
7234 Set_First_Entity (Der_Base, Discr);
7237 Last_Discr := Discr;
7238 Next_Discriminant (Discr);
7239 exit when No (Discr);
7242 Set_Last_Entity (Der_Base, Last_Discr);
7243 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
7244 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
7246 Set_Stored_Constraint
7247 (Full_Der, Stored_Constraint (Derived_Type));
7251 elsif Present (Full_View (Parent_Type))
7252 and then Has_Discriminants (Full_View (Parent_Type))
7254 if Has_Unknown_Discriminants (Parent_Type)
7255 and then Nkind (Subtype_Indication (Type_Definition (N))) =
7256 N_Subtype_Indication
7259 ("cannot constrain type with unknown discriminants",
7260 Subtype_Indication (Type_Definition (N)));
7264 -- If this is not a completion, construct the implicit full view by
7265 -- deriving from the full view of the parent type. But if this is a
7266 -- completion, the derived private type being built is a full view
7267 -- and the full derivation can only be its underlying full view.
7269 Build_Full_Derivation;
7271 if not Is_Completion then
7272 Set_Full_View (Derived_Type, Full_Der);
7274 Set_Underlying_Full_View (Derived_Type, Full_Der);
7277 -- In any case, the primitive operations are inherited from the
7278 -- parent type, not from the internal full view.
7280 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
7282 if Derive_Subps then
7283 Derive_Subprograms (Parent_Type, Derived_Type);
7286 Set_Stored_Constraint (Derived_Type, No_Elist);
7288 (Derived_Type, Is_Constrained (Full_View (Parent_Type)));
7291 -- Untagged type, No discriminants on either view
7293 if Nkind (Subtype_Indication (Type_Definition (N))) =
7294 N_Subtype_Indication
7297 ("illegal constraint on type without discriminants", N);
7300 if Present (Discriminant_Specifications (N))
7301 and then Present (Full_View (Parent_Type))
7302 and then not Is_Tagged_Type (Full_View (Parent_Type))
7304 Error_Msg_N ("cannot add discriminants to untagged type", N);
7307 Set_Stored_Constraint (Derived_Type, No_Elist);
7308 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7309 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7310 Set_Has_Controlled_Component
7311 (Derived_Type, Has_Controlled_Component
7314 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7316 if not Is_Controlled (Parent_Type) then
7317 Set_Finalize_Storage_Only
7318 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
7321 -- If this is not a completion, construct the implicit full view by
7322 -- deriving from the full view of the parent type.
7324 -- ??? If the parent is untagged private and its completion is
7325 -- tagged, this mechanism will not work because we cannot derive from
7326 -- the tagged full view unless we have an extension.
7328 if Present (Full_View (Parent_Type))
7329 and then not Is_Tagged_Type (Full_View (Parent_Type))
7330 and then not Is_Completion
7332 Build_Full_Derivation;
7333 Set_Full_View (Derived_Type, Full_Der);
7337 Set_Has_Unknown_Discriminants (Derived_Type,
7338 Has_Unknown_Discriminants (Parent_Type));
7340 if Is_Private_Type (Derived_Type) then
7341 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7344 -- If the parent base type is in scope, add the derived type to its
7345 -- list of private dependents, because its full view may become
7346 -- visible subsequently (in a nested private part, a body, or in a
7347 -- further child unit).
7349 if Is_Private_Type (Par_Base) and then In_Open_Scopes (Par_Scope) then
7350 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
7352 -- Check for unusual case where a type completed by a private
7353 -- derivation occurs within a package nested in a child unit, and
7354 -- the parent is declared in an ancestor.
7356 if Is_Child_Unit (Scope (Current_Scope))
7357 and then Is_Completion
7358 and then In_Private_Part (Current_Scope)
7359 and then Scope (Parent_Type) /= Current_Scope
7361 -- Note that if the parent has a completion in the private part,
7362 -- (which is itself a derivation from some other private type)
7363 -- it is that completion that is visible, there is no full view
7364 -- available, and no special processing is needed.
7366 and then Present (Full_View (Parent_Type))
7368 -- In this case, the full view of the parent type will become
7369 -- visible in the body of the enclosing child, and only then will
7370 -- the current type be possibly non-private. Build an underlying
7371 -- full view that will be installed when the enclosing child body
7374 if Present (Underlying_Full_View (Derived_Type)) then
7375 Full_Der := Underlying_Full_View (Derived_Type);
7377 Build_Full_Derivation;
7378 Set_Underlying_Full_View (Derived_Type, Full_Der);
7381 -- The full view will be used to swap entities on entry/exit to
7382 -- the body, and must appear in the entity list for the package.
7384 Append_Entity (Full_Der, Scope (Derived_Type));
7387 end Build_Derived_Private_Type;
7389 -------------------------------
7390 -- Build_Derived_Record_Type --
7391 -------------------------------
7395 -- Ideally we would like to use the same model of type derivation for
7396 -- tagged and untagged record types. Unfortunately this is not quite
7397 -- possible because the semantics of representation clauses is different
7398 -- for tagged and untagged records under inheritance. Consider the
7401 -- type R (...) is [tagged] record ... end record;
7402 -- type T (...) is new R (...) [with ...];
7404 -- The representation clauses for T can specify a completely different
7405 -- record layout from R's. Hence the same component can be placed in two
7406 -- very different positions in objects of type T and R. If R and T are
7407 -- tagged types, representation clauses for T can only specify the layout
7408 -- of non inherited components, thus components that are common in R and T
7409 -- have the same position in objects of type R and T.
7411 -- This has two implications. The first is that the entire tree for R's
7412 -- declaration needs to be copied for T in the untagged case, so that T
7413 -- can be viewed as a record type of its own with its own representation
7414 -- clauses. The second implication is the way we handle discriminants.
7415 -- Specifically, in the untagged case we need a way to communicate to Gigi
7416 -- what are the real discriminants in the record, while for the semantics
7417 -- we need to consider those introduced by the user to rename the
7418 -- discriminants in the parent type. This is handled by introducing the
7419 -- notion of stored discriminants. See below for more.
7421 -- Fortunately the way regular components are inherited can be handled in
7422 -- the same way in tagged and untagged types.
7424 -- To complicate things a bit more the private view of a private extension
7425 -- cannot be handled in the same way as the full view (for one thing the
7426 -- semantic rules are somewhat different). We will explain what differs
7429 -- 2. DISCRIMINANTS UNDER INHERITANCE
7431 -- The semantic rules governing the discriminants of derived types are
7434 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
7435 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
7437 -- If parent type has discriminants, then the discriminants that are
7438 -- declared in the derived type are [3.4 (11)]:
7440 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
7443 -- o Otherwise, each discriminant of the parent type (implicitly declared
7444 -- in the same order with the same specifications). In this case, the
7445 -- discriminants are said to be "inherited", or if unknown in the parent
7446 -- are also unknown in the derived type.
7448 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
7450 -- o The parent subtype must be constrained;
7452 -- o If the parent type is not a tagged type, then each discriminant of
7453 -- the derived type must be used in the constraint defining a parent
7454 -- subtype. [Implementation note: This ensures that the new discriminant
7455 -- can share storage with an existing discriminant.]
7457 -- For the derived type each discriminant of the parent type is either
7458 -- inherited, constrained to equal some new discriminant of the derived
7459 -- type, or constrained to the value of an expression.
7461 -- When inherited or constrained to equal some new discriminant, the
7462 -- parent discriminant and the discriminant of the derived type are said
7465 -- If a discriminant of the parent type is constrained to a specific value
7466 -- in the derived type definition, then the discriminant is said to be
7467 -- "specified" by that derived type definition.
7469 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
7471 -- We have spoken about stored discriminants in point 1 (introduction)
7472 -- above. There are two sort of stored discriminants: implicit and
7473 -- explicit. As long as the derived type inherits the same discriminants as
7474 -- the root record type, stored discriminants are the same as regular
7475 -- discriminants, and are said to be implicit. However, if any discriminant
7476 -- in the root type was renamed in the derived type, then the derived
7477 -- type will contain explicit stored discriminants. Explicit stored
7478 -- discriminants are discriminants in addition to the semantically visible
7479 -- discriminants defined for the derived type. Stored discriminants are
7480 -- used by Gigi to figure out what are the physical discriminants in
7481 -- objects of the derived type (see precise definition in einfo.ads).
7482 -- As an example, consider the following:
7484 -- type R (D1, D2, D3 : Int) is record ... end record;
7485 -- type T1 is new R;
7486 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
7487 -- type T3 is new T2;
7488 -- type T4 (Y : Int) is new T3 (Y, 99);
7490 -- The following table summarizes the discriminants and stored
7491 -- discriminants in R and T1 through T4.
7493 -- Type Discrim Stored Discrim Comment
7494 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
7495 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
7496 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
7497 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
7498 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
7500 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
7501 -- find the corresponding discriminant in the parent type, while
7502 -- Original_Record_Component (abbreviated ORC below), the actual physical
7503 -- component that is renamed. Finally the field Is_Completely_Hidden
7504 -- (abbreviated ICH below) is set for all explicit stored discriminants
7505 -- (see einfo.ads for more info). For the above example this gives:
7507 -- Discrim CD ORC ICH
7508 -- ^^^^^^^ ^^ ^^^ ^^^
7509 -- D1 in R empty itself no
7510 -- D2 in R empty itself no
7511 -- D3 in R empty itself no
7513 -- D1 in T1 D1 in R itself no
7514 -- D2 in T1 D2 in R itself no
7515 -- D3 in T1 D3 in R itself no
7517 -- X1 in T2 D3 in T1 D3 in T2 no
7518 -- X2 in T2 D1 in T1 D1 in T2 no
7519 -- D1 in T2 empty itself yes
7520 -- D2 in T2 empty itself yes
7521 -- D3 in T2 empty itself yes
7523 -- X1 in T3 X1 in T2 D3 in T3 no
7524 -- X2 in T3 X2 in T2 D1 in T3 no
7525 -- D1 in T3 empty itself yes
7526 -- D2 in T3 empty itself yes
7527 -- D3 in T3 empty itself yes
7529 -- Y in T4 X1 in T3 D3 in T3 no
7530 -- D1 in T3 empty itself yes
7531 -- D2 in T3 empty itself yes
7532 -- D3 in T3 empty itself yes
7534 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
7536 -- Type derivation for tagged types is fairly straightforward. If no
7537 -- discriminants are specified by the derived type, these are inherited
7538 -- from the parent. No explicit stored discriminants are ever necessary.
7539 -- The only manipulation that is done to the tree is that of adding a
7540 -- _parent field with parent type and constrained to the same constraint
7541 -- specified for the parent in the derived type definition. For instance:
7543 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
7544 -- type T1 is new R with null record;
7545 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
7547 -- are changed into:
7549 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
7550 -- _parent : R (D1, D2, D3);
7553 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
7554 -- _parent : T1 (X2, 88, X1);
7557 -- The discriminants actually present in R, T1 and T2 as well as their CD,
7558 -- ORC and ICH fields are:
7560 -- Discrim CD ORC ICH
7561 -- ^^^^^^^ ^^ ^^^ ^^^
7562 -- D1 in R empty itself no
7563 -- D2 in R empty itself no
7564 -- D3 in R empty itself no
7566 -- D1 in T1 D1 in R D1 in R no
7567 -- D2 in T1 D2 in R D2 in R no
7568 -- D3 in T1 D3 in R D3 in R no
7570 -- X1 in T2 D3 in T1 D3 in R no
7571 -- X2 in T2 D1 in T1 D1 in R no
7573 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
7575 -- Regardless of whether we dealing with a tagged or untagged type
7576 -- we will transform all derived type declarations of the form
7578 -- type T is new R (...) [with ...];
7580 -- subtype S is R (...);
7581 -- type T is new S [with ...];
7583 -- type BT is new R [with ...];
7584 -- subtype T is BT (...);
7586 -- That is, the base derived type is constrained only if it has no
7587 -- discriminants. The reason for doing this is that GNAT's semantic model
7588 -- assumes that a base type with discriminants is unconstrained.
7590 -- Note that, strictly speaking, the above transformation is not always
7591 -- correct. Consider for instance the following excerpt from ACVC b34011a:
7593 -- procedure B34011A is
7594 -- type REC (D : integer := 0) is record
7599 -- type T6 is new Rec;
7600 -- function F return T6;
7605 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
7608 -- The definition of Q6.U is illegal. However transforming Q6.U into
7610 -- type BaseU is new T6;
7611 -- subtype U is BaseU (Q6.F.I)
7613 -- turns U into a legal subtype, which is incorrect. To avoid this problem
7614 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
7615 -- the transformation described above.
7617 -- There is another instance where the above transformation is incorrect.
7621 -- type Base (D : Integer) is tagged null record;
7622 -- procedure P (X : Base);
7624 -- type Der is new Base (2) with null record;
7625 -- procedure P (X : Der);
7628 -- Then the above transformation turns this into
7630 -- type Der_Base is new Base with null record;
7631 -- -- procedure P (X : Base) is implicitly inherited here
7632 -- -- as procedure P (X : Der_Base).
7634 -- subtype Der is Der_Base (2);
7635 -- procedure P (X : Der);
7636 -- -- The overriding of P (X : Der_Base) is illegal since we
7637 -- -- have a parameter conformance problem.
7639 -- To get around this problem, after having semantically processed Der_Base
7640 -- and the rewritten subtype declaration for Der, we copy Der_Base field
7641 -- Discriminant_Constraint from Der so that when parameter conformance is
7642 -- checked when P is overridden, no semantic errors are flagged.
7644 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
7646 -- Regardless of whether we are dealing with a tagged or untagged type
7647 -- we will transform all derived type declarations of the form
7649 -- type R (D1, .., Dn : ...) is [tagged] record ...;
7650 -- type T is new R [with ...];
7652 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
7654 -- The reason for such transformation is that it allows us to implement a
7655 -- very clean form of component inheritance as explained below.
7657 -- Note that this transformation is not achieved by direct tree rewriting
7658 -- and manipulation, but rather by redoing the semantic actions that the
7659 -- above transformation will entail. This is done directly in routine
7660 -- Inherit_Components.
7662 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
7664 -- In both tagged and untagged derived types, regular non discriminant
7665 -- components are inherited in the derived type from the parent type. In
7666 -- the absence of discriminants component, inheritance is straightforward
7667 -- as components can simply be copied from the parent.
7669 -- If the parent has discriminants, inheriting components constrained with
7670 -- these discriminants requires caution. Consider the following example:
7672 -- type R (D1, D2 : Positive) is [tagged] record
7673 -- S : String (D1 .. D2);
7676 -- type T1 is new R [with null record];
7677 -- type T2 (X : positive) is new R (1, X) [with null record];
7679 -- As explained in 6. above, T1 is rewritten as
7680 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
7681 -- which makes the treatment for T1 and T2 identical.
7683 -- What we want when inheriting S, is that references to D1 and D2 in R are
7684 -- replaced with references to their correct constraints, i.e. D1 and D2 in
7685 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
7686 -- with either discriminant references in the derived type or expressions.
7687 -- This replacement is achieved as follows: before inheriting R's
7688 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
7689 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
7690 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
7691 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
7692 -- by String (1 .. X).
7694 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
7696 -- We explain here the rules governing private type extensions relevant to
7697 -- type derivation. These rules are explained on the following example:
7699 -- type D [(...)] is new A [(...)] with private; <-- partial view
7700 -- type D [(...)] is new P [(...)] with null record; <-- full view
7702 -- Type A is called the ancestor subtype of the private extension.
7703 -- Type P is the parent type of the full view of the private extension. It
7704 -- must be A or a type derived from A.
7706 -- The rules concerning the discriminants of private type extensions are
7709 -- o If a private extension inherits known discriminants from the ancestor
7710 -- subtype, then the full view must also inherit its discriminants from
7711 -- the ancestor subtype and the parent subtype of the full view must be
7712 -- constrained if and only if the ancestor subtype is constrained.
7714 -- o If a partial view has unknown discriminants, then the full view may
7715 -- define a definite or an indefinite subtype, with or without
7718 -- o If a partial view has neither known nor unknown discriminants, then
7719 -- the full view must define a definite subtype.
7721 -- o If the ancestor subtype of a private extension has constrained
7722 -- discriminants, then the parent subtype of the full view must impose a
7723 -- statically matching constraint on those discriminants.
7725 -- This means that only the following forms of private extensions are
7728 -- type D is new A with private; <-- partial view
7729 -- type D is new P with null record; <-- full view
7731 -- If A has no discriminants than P has no discriminants, otherwise P must
7732 -- inherit A's discriminants.
7734 -- type D is new A (...) with private; <-- partial view
7735 -- type D is new P (:::) with null record; <-- full view
7737 -- P must inherit A's discriminants and (...) and (:::) must statically
7740 -- subtype A is R (...);
7741 -- type D is new A with private; <-- partial view
7742 -- type D is new P with null record; <-- full view
7744 -- P must have inherited R's discriminants and must be derived from A or
7745 -- any of its subtypes.
7747 -- type D (..) is new A with private; <-- partial view
7748 -- type D (..) is new P [(:::)] with null record; <-- full view
7750 -- No specific constraints on P's discriminants or constraint (:::).
7751 -- Note that A can be unconstrained, but the parent subtype P must either
7752 -- be constrained or (:::) must be present.
7754 -- type D (..) is new A [(...)] with private; <-- partial view
7755 -- type D (..) is new P [(:::)] with null record; <-- full view
7757 -- P's constraints on A's discriminants must statically match those
7758 -- imposed by (...).
7760 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
7762 -- The full view of a private extension is handled exactly as described
7763 -- above. The model chose for the private view of a private extension is
7764 -- the same for what concerns discriminants (i.e. they receive the same
7765 -- treatment as in the tagged case). However, the private view of the
7766 -- private extension always inherits the components of the parent base,
7767 -- without replacing any discriminant reference. Strictly speaking this is
7768 -- incorrect. However, Gigi never uses this view to generate code so this
7769 -- is a purely semantic issue. In theory, a set of transformations similar
7770 -- to those given in 5. and 6. above could be applied to private views of
7771 -- private extensions to have the same model of component inheritance as
7772 -- for non private extensions. However, this is not done because it would
7773 -- further complicate private type processing. Semantically speaking, this
7774 -- leaves us in an uncomfortable situation. As an example consider:
7777 -- type R (D : integer) is tagged record
7778 -- S : String (1 .. D);
7780 -- procedure P (X : R);
7781 -- type T is new R (1) with private;
7783 -- type T is new R (1) with null record;
7786 -- This is transformed into:
7789 -- type R (D : integer) is tagged record
7790 -- S : String (1 .. D);
7792 -- procedure P (X : R);
7793 -- type T is new R (1) with private;
7795 -- type BaseT is new R with null record;
7796 -- subtype T is BaseT (1);
7799 -- (strictly speaking the above is incorrect Ada)
7801 -- From the semantic standpoint the private view of private extension T
7802 -- should be flagged as constrained since one can clearly have
7806 -- in a unit withing Pack. However, when deriving subprograms for the
7807 -- private view of private extension T, T must be seen as unconstrained
7808 -- since T has discriminants (this is a constraint of the current
7809 -- subprogram derivation model). Thus, when processing the private view of
7810 -- a private extension such as T, we first mark T as unconstrained, we
7811 -- process it, we perform program derivation and just before returning from
7812 -- Build_Derived_Record_Type we mark T as constrained.
7814 -- ??? Are there are other uncomfortable cases that we will have to
7817 -- 10. RECORD_TYPE_WITH_PRIVATE complications
7819 -- Types that are derived from a visible record type and have a private
7820 -- extension present other peculiarities. They behave mostly like private
7821 -- types, but if they have primitive operations defined, these will not
7822 -- have the proper signatures for further inheritance, because other
7823 -- primitive operations will use the implicit base that we define for
7824 -- private derivations below. This affect subprogram inheritance (see
7825 -- Derive_Subprograms for details). We also derive the implicit base from
7826 -- the base type of the full view, so that the implicit base is a record
7827 -- type and not another private type, This avoids infinite loops.
7829 procedure Build_Derived_Record_Type
7831 Parent_Type : Entity_Id;
7832 Derived_Type : Entity_Id;
7833 Derive_Subps : Boolean := True)
7835 Discriminant_Specs : constant Boolean :=
7836 Present (Discriminant_Specifications (N));
7837 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
7838 Loc : constant Source_Ptr := Sloc (N);
7839 Private_Extension : constant Boolean :=
7840 Nkind (N) = N_Private_Extension_Declaration;
7841 Assoc_List : Elist_Id;
7842 Constraint_Present : Boolean;
7844 Discrim : Entity_Id;
7846 Inherit_Discrims : Boolean := False;
7847 Last_Discrim : Entity_Id;
7848 New_Base : Entity_Id;
7850 New_Discrs : Elist_Id;
7851 New_Indic : Node_Id;
7852 Parent_Base : Entity_Id;
7853 Save_Etype : Entity_Id;
7854 Save_Discr_Constr : Elist_Id;
7855 Save_Next_Entity : Entity_Id;
7858 Discs : Elist_Id := New_Elmt_List;
7859 -- An empty Discs list means that there were no constraints in the
7860 -- subtype indication or that there was an error processing it.
7863 if Ekind (Parent_Type) = E_Record_Type_With_Private
7864 and then Present (Full_View (Parent_Type))
7865 and then Has_Discriminants (Parent_Type)
7867 Parent_Base := Base_Type (Full_View (Parent_Type));
7869 Parent_Base := Base_Type (Parent_Type);
7872 -- AI05-0115 : if this is a derivation from a private type in some
7873 -- other scope that may lead to invisible components for the derived
7874 -- type, mark it accordingly.
7876 if Is_Private_Type (Parent_Type) then
7877 if Scope (Parent_Type) = Scope (Derived_Type) then
7880 elsif In_Open_Scopes (Scope (Parent_Type))
7881 and then In_Private_Part (Scope (Parent_Type))
7886 Set_Has_Private_Ancestor (Derived_Type);
7890 Set_Has_Private_Ancestor
7891 (Derived_Type, Has_Private_Ancestor (Parent_Type));
7894 -- Before we start the previously documented transformations, here is
7895 -- little fix for size and alignment of tagged types. Normally when we
7896 -- derive type D from type P, we copy the size and alignment of P as the
7897 -- default for D, and in the absence of explicit representation clauses
7898 -- for D, the size and alignment are indeed the same as the parent.
7900 -- But this is wrong for tagged types, since fields may be added, and
7901 -- the default size may need to be larger, and the default alignment may
7902 -- need to be larger.
7904 -- We therefore reset the size and alignment fields in the tagged case.
7905 -- Note that the size and alignment will in any case be at least as
7906 -- large as the parent type (since the derived type has a copy of the
7907 -- parent type in the _parent field)
7909 -- The type is also marked as being tagged here, which is needed when
7910 -- processing components with a self-referential anonymous access type
7911 -- in the call to Check_Anonymous_Access_Components below. Note that
7912 -- this flag is also set later on for completeness.
7915 Set_Is_Tagged_Type (Derived_Type);
7916 Init_Size_Align (Derived_Type);
7919 -- STEP 0a: figure out what kind of derived type declaration we have
7921 if Private_Extension then
7923 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
7924 Set_Default_SSO (Derived_Type);
7927 Type_Def := Type_Definition (N);
7929 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7930 -- Parent_Base can be a private type or private extension. However,
7931 -- for tagged types with an extension the newly added fields are
7932 -- visible and hence the Derived_Type is always an E_Record_Type.
7933 -- (except that the parent may have its own private fields).
7934 -- For untagged types we preserve the Ekind of the Parent_Base.
7936 if Present (Record_Extension_Part (Type_Def)) then
7937 Set_Ekind (Derived_Type, E_Record_Type);
7938 Set_Default_SSO (Derived_Type);
7940 -- Create internal access types for components with anonymous
7943 if Ada_Version >= Ada_2005 then
7944 Check_Anonymous_Access_Components
7945 (N, Derived_Type, Derived_Type,
7946 Component_List (Record_Extension_Part (Type_Def)));
7950 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7954 -- Indic can either be an N_Identifier if the subtype indication
7955 -- contains no constraint or an N_Subtype_Indication if the subtype
7956 -- indication has a constraint.
7958 Indic := Subtype_Indication (Type_Def);
7959 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
7961 -- Check that the type has visible discriminants. The type may be
7962 -- a private type with unknown discriminants whose full view has
7963 -- discriminants which are invisible.
7965 if Constraint_Present then
7966 if not Has_Discriminants (Parent_Base)
7968 (Has_Unknown_Discriminants (Parent_Base)
7969 and then Is_Private_Type (Parent_Base))
7972 ("invalid constraint: type has no discriminant",
7973 Constraint (Indic));
7975 Constraint_Present := False;
7976 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7978 elsif Is_Constrained (Parent_Type) then
7980 ("invalid constraint: parent type is already constrained",
7981 Constraint (Indic));
7983 Constraint_Present := False;
7984 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7988 -- STEP 0b: If needed, apply transformation given in point 5. above
7990 if not Private_Extension
7991 and then Has_Discriminants (Parent_Type)
7992 and then not Discriminant_Specs
7993 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
7995 -- First, we must analyze the constraint (see comment in point 5.)
7996 -- The constraint may come from the subtype indication of the full
7999 if Constraint_Present then
8000 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
8002 -- If there is no explicit constraint, there might be one that is
8003 -- inherited from a constrained parent type. In that case verify that
8004 -- it conforms to the constraint in the partial view. In perverse
8005 -- cases the parent subtypes of the partial and full view can have
8006 -- different constraints.
8008 elsif Present (Stored_Constraint (Parent_Type)) then
8009 New_Discrs := Stored_Constraint (Parent_Type);
8012 New_Discrs := No_Elist;
8015 if Has_Discriminants (Derived_Type)
8016 and then Has_Private_Declaration (Derived_Type)
8017 and then Present (Discriminant_Constraint (Derived_Type))
8018 and then Present (New_Discrs)
8020 -- Verify that constraints of the full view statically match
8021 -- those given in the partial view.
8027 C1 := First_Elmt (New_Discrs);
8028 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
8029 while Present (C1) and then Present (C2) loop
8030 if Fully_Conformant_Expressions (Node (C1), Node (C2))
8032 (Is_OK_Static_Expression (Node (C1))
8033 and then Is_OK_Static_Expression (Node (C2))
8035 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
8040 if Constraint_Present then
8042 ("constraint not conformant to previous declaration",
8046 ("constraint of full view is incompatible "
8047 & "with partial view", N);
8057 -- Insert and analyze the declaration for the unconstrained base type
8059 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
8062 Make_Full_Type_Declaration (Loc,
8063 Defining_Identifier => New_Base,
8065 Make_Derived_Type_Definition (Loc,
8066 Abstract_Present => Abstract_Present (Type_Def),
8067 Limited_Present => Limited_Present (Type_Def),
8068 Subtype_Indication =>
8069 New_Occurrence_Of (Parent_Base, Loc),
8070 Record_Extension_Part =>
8071 Relocate_Node (Record_Extension_Part (Type_Def)),
8072 Interface_List => Interface_List (Type_Def)));
8074 Set_Parent (New_Decl, Parent (N));
8075 Mark_Rewrite_Insertion (New_Decl);
8076 Insert_Before (N, New_Decl);
8078 -- In the extension case, make sure ancestor is frozen appropriately
8079 -- (see also non-discriminated case below).
8081 if Present (Record_Extension_Part (Type_Def))
8082 or else Is_Interface (Parent_Base)
8084 Freeze_Before (New_Decl, Parent_Type);
8087 -- Note that this call passes False for the Derive_Subps parameter
8088 -- because subprogram derivation is deferred until after creating
8089 -- the subtype (see below).
8092 (New_Decl, Parent_Base, New_Base,
8093 Is_Completion => False, Derive_Subps => False);
8095 -- ??? This needs re-examination to determine whether the
8096 -- above call can simply be replaced by a call to Analyze.
8098 Set_Analyzed (New_Decl);
8100 -- Insert and analyze the declaration for the constrained subtype
8102 if Constraint_Present then
8104 Make_Subtype_Indication (Loc,
8105 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8106 Constraint => Relocate_Node (Constraint (Indic)));
8110 Constr_List : constant List_Id := New_List;
8115 C := First_Elmt (Discriminant_Constraint (Parent_Type));
8116 while Present (C) loop
8119 -- It is safe here to call New_Copy_Tree since we called
8120 -- Force_Evaluation on each constraint previously
8121 -- in Build_Discriminant_Constraints.
8123 Append (New_Copy_Tree (Expr), To => Constr_List);
8129 Make_Subtype_Indication (Loc,
8130 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8132 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
8137 Make_Subtype_Declaration (Loc,
8138 Defining_Identifier => Derived_Type,
8139 Subtype_Indication => New_Indic));
8143 -- Derivation of subprograms must be delayed until the full subtype
8144 -- has been established, to ensure proper overriding of subprograms
8145 -- inherited by full types. If the derivations occurred as part of
8146 -- the call to Build_Derived_Type above, then the check for type
8147 -- conformance would fail because earlier primitive subprograms
8148 -- could still refer to the full type prior the change to the new
8149 -- subtype and hence would not match the new base type created here.
8150 -- Subprograms are not derived, however, when Derive_Subps is False
8151 -- (since otherwise there could be redundant derivations).
8153 if Derive_Subps then
8154 Derive_Subprograms (Parent_Type, Derived_Type);
8157 -- For tagged types the Discriminant_Constraint of the new base itype
8158 -- is inherited from the first subtype so that no subtype conformance
8159 -- problem arise when the first subtype overrides primitive
8160 -- operations inherited by the implicit base type.
8163 Set_Discriminant_Constraint
8164 (New_Base, Discriminant_Constraint (Derived_Type));
8170 -- If we get here Derived_Type will have no discriminants or it will be
8171 -- a discriminated unconstrained base type.
8173 -- STEP 1a: perform preliminary actions/checks for derived tagged types
8177 -- The parent type is frozen for non-private extensions (RM 13.14(7))
8178 -- The declaration of a specific descendant of an interface type
8179 -- freezes the interface type (RM 13.14).
8181 if not Private_Extension or else Is_Interface (Parent_Base) then
8182 Freeze_Before (N, Parent_Type);
8185 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
8186 -- cannot be declared at a deeper level than its parent type is
8187 -- removed. The check on derivation within a generic body is also
8188 -- relaxed, but there's a restriction that a derived tagged type
8189 -- cannot be declared in a generic body if it's derived directly
8190 -- or indirectly from a formal type of that generic.
8192 if Ada_Version >= Ada_2005 then
8193 if Present (Enclosing_Generic_Body (Derived_Type)) then
8195 Ancestor_Type : Entity_Id;
8198 -- Check to see if any ancestor of the derived type is a
8201 Ancestor_Type := Parent_Type;
8202 while not Is_Generic_Type (Ancestor_Type)
8203 and then Etype (Ancestor_Type) /= Ancestor_Type
8205 Ancestor_Type := Etype (Ancestor_Type);
8208 -- If the derived type does have a formal type as an
8209 -- ancestor, then it's an error if the derived type is
8210 -- declared within the body of the generic unit that
8211 -- declares the formal type in its generic formal part. It's
8212 -- sufficient to check whether the ancestor type is declared
8213 -- inside the same generic body as the derived type (such as
8214 -- within a nested generic spec), in which case the
8215 -- derivation is legal. If the formal type is declared
8216 -- outside of that generic body, then it's guaranteed that
8217 -- the derived type is declared within the generic body of
8218 -- the generic unit declaring the formal type.
8220 if Is_Generic_Type (Ancestor_Type)
8221 and then Enclosing_Generic_Body (Ancestor_Type) /=
8222 Enclosing_Generic_Body (Derived_Type)
8225 ("parent type of& must not be descendant of formal type"
8226 & " of an enclosing generic body",
8227 Indic, Derived_Type);
8232 elsif Type_Access_Level (Derived_Type) /=
8233 Type_Access_Level (Parent_Type)
8234 and then not Is_Generic_Type (Derived_Type)
8236 if Is_Controlled (Parent_Type) then
8238 ("controlled type must be declared at the library level",
8242 ("type extension at deeper accessibility level than parent",
8248 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
8251 and then GB /= Enclosing_Generic_Body (Parent_Base)
8254 ("parent type of& must not be outside generic body"
8256 Indic, Derived_Type);
8262 -- Ada 2005 (AI-251)
8264 if Ada_Version >= Ada_2005 and then Is_Tagged then
8266 -- "The declaration of a specific descendant of an interface type
8267 -- freezes the interface type" (RM 13.14).
8272 if Is_Non_Empty_List (Interface_List (Type_Def)) then
8273 Iface := First (Interface_List (Type_Def));
8274 while Present (Iface) loop
8275 Freeze_Before (N, Etype (Iface));
8282 -- STEP 1b : preliminary cleanup of the full view of private types
8284 -- If the type is already marked as having discriminants, then it's the
8285 -- completion of a private type or private extension and we need to
8286 -- retain the discriminants from the partial view if the current
8287 -- declaration has Discriminant_Specifications so that we can verify
8288 -- conformance. However, we must remove any existing components that
8289 -- were inherited from the parent (and attached in Copy_And_Swap)
8290 -- because the full type inherits all appropriate components anyway, and
8291 -- we do not want the partial view's components interfering.
8293 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
8294 Discrim := First_Discriminant (Derived_Type);
8296 Last_Discrim := Discrim;
8297 Next_Discriminant (Discrim);
8298 exit when No (Discrim);
8301 Set_Last_Entity (Derived_Type, Last_Discrim);
8303 -- In all other cases wipe out the list of inherited components (even
8304 -- inherited discriminants), it will be properly rebuilt here.
8307 Set_First_Entity (Derived_Type, Empty);
8308 Set_Last_Entity (Derived_Type, Empty);
8311 -- STEP 1c: Initialize some flags for the Derived_Type
8313 -- The following flags must be initialized here so that
8314 -- Process_Discriminants can check that discriminants of tagged types do
8315 -- not have a default initial value and that access discriminants are
8316 -- only specified for limited records. For completeness, these flags are
8317 -- also initialized along with all the other flags below.
8319 -- AI-419: Limitedness is not inherited from an interface parent, so to
8320 -- be limited in that case the type must be explicitly declared as
8321 -- limited. However, task and protected interfaces are always limited.
8323 if Limited_Present (Type_Def) then
8324 Set_Is_Limited_Record (Derived_Type);
8326 elsif Is_Limited_Record (Parent_Type)
8327 or else (Present (Full_View (Parent_Type))
8328 and then Is_Limited_Record (Full_View (Parent_Type)))
8330 if not Is_Interface (Parent_Type)
8331 or else Is_Synchronized_Interface (Parent_Type)
8332 or else Is_Protected_Interface (Parent_Type)
8333 or else Is_Task_Interface (Parent_Type)
8335 Set_Is_Limited_Record (Derived_Type);
8339 -- STEP 2a: process discriminants of derived type if any
8341 Push_Scope (Derived_Type);
8343 if Discriminant_Specs then
8344 Set_Has_Unknown_Discriminants (Derived_Type, False);
8346 -- The following call initializes fields Has_Discriminants and
8347 -- Discriminant_Constraint, unless we are processing the completion
8348 -- of a private type declaration.
8350 Check_Or_Process_Discriminants (N, Derived_Type);
8352 -- For untagged types, the constraint on the Parent_Type must be
8353 -- present and is used to rename the discriminants.
8355 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
8356 Error_Msg_N ("untagged parent must have discriminants", Indic);
8358 elsif not Is_Tagged and then not Constraint_Present then
8360 ("discriminant constraint needed for derived untagged records",
8363 -- Otherwise the parent subtype must be constrained unless we have a
8364 -- private extension.
8366 elsif not Constraint_Present
8367 and then not Private_Extension
8368 and then not Is_Constrained (Parent_Type)
8371 ("unconstrained type not allowed in this context", Indic);
8373 elsif Constraint_Present then
8374 -- The following call sets the field Corresponding_Discriminant
8375 -- for the discriminants in the Derived_Type.
8377 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
8379 -- For untagged types all new discriminants must rename
8380 -- discriminants in the parent. For private extensions new
8381 -- discriminants cannot rename old ones (implied by [7.3(13)]).
8383 Discrim := First_Discriminant (Derived_Type);
8384 while Present (Discrim) loop
8386 and then No (Corresponding_Discriminant (Discrim))
8389 ("new discriminants must constrain old ones", Discrim);
8391 elsif Private_Extension
8392 and then Present (Corresponding_Discriminant (Discrim))
8395 ("only static constraints allowed for parent"
8396 & " discriminants in the partial view", Indic);
8400 -- If a new discriminant is used in the constraint, then its
8401 -- subtype must be statically compatible with the parent
8402 -- discriminant's subtype (3.7(15)).
8404 -- However, if the record contains an array constrained by
8405 -- the discriminant but with some different bound, the compiler
8406 -- attemps to create a smaller range for the discriminant type.
8407 -- (See exp_ch3.Adjust_Discriminants). In this case, where
8408 -- the discriminant type is a scalar type, the check must use
8409 -- the original discriminant type in the parent declaration.
8412 Corr_Disc : constant Entity_Id :=
8413 Corresponding_Discriminant (Discrim);
8414 Disc_Type : constant Entity_Id := Etype (Discrim);
8415 Corr_Type : Entity_Id;
8418 if Present (Corr_Disc) then
8419 if Is_Scalar_Type (Disc_Type) then
8421 Entity (Discriminant_Type (Parent (Corr_Disc)));
8423 Corr_Type := Etype (Corr_Disc);
8427 Subtypes_Statically_Compatible (Disc_Type, Corr_Type)
8430 ("subtype must be compatible "
8431 & "with parent discriminant",
8437 Next_Discriminant (Discrim);
8440 -- Check whether the constraints of the full view statically
8441 -- match those imposed by the parent subtype [7.3(13)].
8443 if Present (Stored_Constraint (Derived_Type)) then
8448 C1 := First_Elmt (Discs);
8449 C2 := First_Elmt (Stored_Constraint (Derived_Type));
8450 while Present (C1) and then Present (C2) loop
8452 Fully_Conformant_Expressions (Node (C1), Node (C2))
8455 ("not conformant with previous declaration",
8466 -- STEP 2b: No new discriminants, inherit discriminants if any
8469 if Private_Extension then
8470 Set_Has_Unknown_Discriminants
8472 Has_Unknown_Discriminants (Parent_Type)
8473 or else Unknown_Discriminants_Present (N));
8475 -- The partial view of the parent may have unknown discriminants,
8476 -- but if the full view has discriminants and the parent type is
8477 -- in scope they must be inherited.
8479 elsif Has_Unknown_Discriminants (Parent_Type)
8481 (not Has_Discriminants (Parent_Type)
8482 or else not In_Open_Scopes (Scope (Parent_Type)))
8484 Set_Has_Unknown_Discriminants (Derived_Type);
8487 if not Has_Unknown_Discriminants (Derived_Type)
8488 and then not Has_Unknown_Discriminants (Parent_Base)
8489 and then Has_Discriminants (Parent_Type)
8491 Inherit_Discrims := True;
8492 Set_Has_Discriminants
8493 (Derived_Type, True);
8494 Set_Discriminant_Constraint
8495 (Derived_Type, Discriminant_Constraint (Parent_Base));
8498 -- The following test is true for private types (remember
8499 -- transformation 5. is not applied to those) and in an error
8502 if Constraint_Present then
8503 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
8506 -- For now mark a new derived type as constrained only if it has no
8507 -- discriminants. At the end of Build_Derived_Record_Type we properly
8508 -- set this flag in the case of private extensions. See comments in
8509 -- point 9. just before body of Build_Derived_Record_Type.
8513 not (Inherit_Discrims
8514 or else Has_Unknown_Discriminants (Derived_Type)));
8517 -- STEP 3: initialize fields of derived type
8519 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
8520 Set_Stored_Constraint (Derived_Type, No_Elist);
8522 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
8523 -- but cannot be interfaces
8525 if not Private_Extension
8526 and then Ekind (Derived_Type) /= E_Private_Type
8527 and then Ekind (Derived_Type) /= E_Limited_Private_Type
8529 if Interface_Present (Type_Def) then
8530 Analyze_Interface_Declaration (Derived_Type, Type_Def);
8533 Set_Interfaces (Derived_Type, No_Elist);
8536 -- Fields inherited from the Parent_Type
8538 Set_Has_Specified_Layout
8539 (Derived_Type, Has_Specified_Layout (Parent_Type));
8540 Set_Is_Limited_Composite
8541 (Derived_Type, Is_Limited_Composite (Parent_Type));
8542 Set_Is_Private_Composite
8543 (Derived_Type, Is_Private_Composite (Parent_Type));
8545 if Is_Tagged_Type (Parent_Type) then
8546 Set_No_Tagged_Streams_Pragma
8547 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8550 -- Fields inherited from the Parent_Base
8552 Set_Has_Controlled_Component
8553 (Derived_Type, Has_Controlled_Component (Parent_Base));
8554 Set_Has_Non_Standard_Rep
8555 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8556 Set_Has_Primitive_Operations
8557 (Derived_Type, Has_Primitive_Operations (Parent_Base));
8559 -- Fields inherited from the Parent_Base in the non-private case
8561 if Ekind (Derived_Type) = E_Record_Type then
8562 Set_Has_Complex_Representation
8563 (Derived_Type, Has_Complex_Representation (Parent_Base));
8566 -- Fields inherited from the Parent_Base for record types
8568 if Is_Record_Type (Derived_Type) then
8570 Parent_Full : Entity_Id;
8573 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8574 -- Parent_Base can be a private type or private extension. Go
8575 -- to the full view here to get the E_Record_Type specific flags.
8577 if Present (Full_View (Parent_Base)) then
8578 Parent_Full := Full_View (Parent_Base);
8580 Parent_Full := Parent_Base;
8583 Set_OK_To_Reorder_Components
8584 (Derived_Type, OK_To_Reorder_Components (Parent_Full));
8588 -- Set fields for private derived types
8590 if Is_Private_Type (Derived_Type) then
8591 Set_Depends_On_Private (Derived_Type, True);
8592 Set_Private_Dependents (Derived_Type, New_Elmt_List);
8594 -- Inherit fields from non private record types. If this is the
8595 -- completion of a derivation from a private type, the parent itself
8596 -- is private, and the attributes come from its full view, which must
8600 if Is_Private_Type (Parent_Base)
8601 and then not Is_Record_Type (Parent_Base)
8603 Set_Component_Alignment
8604 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
8606 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
8608 Set_Component_Alignment
8609 (Derived_Type, Component_Alignment (Parent_Base));
8611 (Derived_Type, C_Pass_By_Copy (Parent_Base));
8615 -- Set fields for tagged types
8618 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
8620 -- All tagged types defined in Ada.Finalization are controlled
8622 if Chars (Scope (Derived_Type)) = Name_Finalization
8623 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
8624 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
8626 Set_Is_Controlled (Derived_Type);
8628 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
8631 -- Minor optimization: there is no need to generate the class-wide
8632 -- entity associated with an underlying record view.
8634 if not Is_Underlying_Record_View (Derived_Type) then
8635 Make_Class_Wide_Type (Derived_Type);
8638 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
8640 if Has_Discriminants (Derived_Type)
8641 and then Constraint_Present
8643 Set_Stored_Constraint
8644 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
8647 if Ada_Version >= Ada_2005 then
8649 Ifaces_List : Elist_Id;
8652 -- Checks rules 3.9.4 (13/2 and 14/2)
8654 if Comes_From_Source (Derived_Type)
8655 and then not Is_Private_Type (Derived_Type)
8656 and then Is_Interface (Parent_Type)
8657 and then not Is_Interface (Derived_Type)
8659 if Is_Task_Interface (Parent_Type) then
8661 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
8664 elsif Is_Protected_Interface (Parent_Type) then
8666 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
8671 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
8673 Check_Interfaces (N, Type_Def);
8675 -- Ada 2005 (AI-251): Collect the list of progenitors that are
8676 -- not already in the parents.
8680 Ifaces_List => Ifaces_List,
8681 Exclude_Parents => True);
8683 Set_Interfaces (Derived_Type, Ifaces_List);
8685 -- If the derived type is the anonymous type created for
8686 -- a declaration whose parent has a constraint, propagate
8687 -- the interface list to the source type. This must be done
8688 -- prior to the completion of the analysis of the source type
8689 -- because the components in the extension may contain current
8690 -- instances whose legality depends on some ancestor.
8692 if Is_Itype (Derived_Type) then
8694 Def : constant Node_Id :=
8695 Associated_Node_For_Itype (Derived_Type);
8698 and then Nkind (Def) = N_Full_Type_Declaration
8701 (Defining_Identifier (Def), Ifaces_List);
8706 -- Propagate inherited invariant information of parents
8709 if Ada_Version >= Ada_2012
8710 and then not Is_Interface (Derived_Type)
8712 if Has_Inheritable_Invariants (Parent_Type) then
8713 Set_Has_Invariants (Derived_Type);
8714 Set_Has_Inheritable_Invariants (Derived_Type);
8716 elsif not Is_Empty_Elmt_List (Ifaces_List) then
8721 AI := First_Elmt (Ifaces_List);
8722 while Present (AI) loop
8723 if Has_Inheritable_Invariants (Node (AI)) then
8724 Set_Has_Invariants (Derived_Type);
8725 Set_Has_Inheritable_Invariants (Derived_Type);
8736 -- A type extension is automatically Ghost when one of its
8737 -- progenitors is Ghost (SPARK RM 6.9(9)). This property is
8738 -- also inherited when the parent type is Ghost, but this is
8739 -- done in Build_Derived_Type as the mechanism also handles
8740 -- untagged derivations.
8742 if Implements_Ghost_Interface (Derived_Type) then
8743 Set_Is_Ghost_Entity (Derived_Type);
8749 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
8750 Set_Has_Non_Standard_Rep
8751 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8754 -- STEP 4: Inherit components from the parent base and constrain them.
8755 -- Apply the second transformation described in point 6. above.
8757 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
8758 or else not Has_Discriminants (Parent_Type)
8759 or else not Is_Constrained (Parent_Type)
8763 Constrs := Discriminant_Constraint (Parent_Type);
8768 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
8770 -- STEP 5a: Copy the parent record declaration for untagged types
8772 if not Is_Tagged then
8774 -- Discriminant_Constraint (Derived_Type) has been properly
8775 -- constructed. Save it and temporarily set it to Empty because we
8776 -- do not want the call to New_Copy_Tree below to mess this list.
8778 if Has_Discriminants (Derived_Type) then
8779 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
8780 Set_Discriminant_Constraint (Derived_Type, No_Elist);
8782 Save_Discr_Constr := No_Elist;
8785 -- Save the Etype field of Derived_Type. It is correctly set now,
8786 -- but the call to New_Copy tree may remap it to point to itself,
8787 -- which is not what we want. Ditto for the Next_Entity field.
8789 Save_Etype := Etype (Derived_Type);
8790 Save_Next_Entity := Next_Entity (Derived_Type);
8792 -- Assoc_List maps all stored discriminants in the Parent_Base to
8793 -- stored discriminants in the Derived_Type. It is fundamental that
8794 -- no types or itypes with discriminants other than the stored
8795 -- discriminants appear in the entities declared inside
8796 -- Derived_Type, since the back end cannot deal with it.
8800 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
8802 -- Restore the fields saved prior to the New_Copy_Tree call
8803 -- and compute the stored constraint.
8805 Set_Etype (Derived_Type, Save_Etype);
8806 Set_Next_Entity (Derived_Type, Save_Next_Entity);
8808 if Has_Discriminants (Derived_Type) then
8809 Set_Discriminant_Constraint
8810 (Derived_Type, Save_Discr_Constr);
8811 Set_Stored_Constraint
8812 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
8813 Replace_Components (Derived_Type, New_Decl);
8814 Set_Has_Implicit_Dereference
8815 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
8818 -- Insert the new derived type declaration
8820 Rewrite (N, New_Decl);
8822 -- STEP 5b: Complete the processing for record extensions in generics
8824 -- There is no completion for record extensions declared in the
8825 -- parameter part of a generic, so we need to complete processing for
8826 -- these generic record extensions here. The Record_Type_Definition call
8827 -- will change the Ekind of the components from E_Void to E_Component.
8829 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
8830 Record_Type_Definition (Empty, Derived_Type);
8832 -- STEP 5c: Process the record extension for non private tagged types
8834 elsif not Private_Extension then
8835 Expand_Record_Extension (Derived_Type, Type_Def);
8837 -- Note : previously in ASIS mode we set the Parent_Subtype of the
8838 -- derived type to propagate some semantic information. This led
8839 -- to other ASIS failures and has been removed.
8841 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
8842 -- implemented interfaces if we are in expansion mode
8845 and then Has_Interfaces (Derived_Type)
8847 Add_Interface_Tag_Components (N, Derived_Type);
8850 -- Analyze the record extension
8852 Record_Type_Definition
8853 (Record_Extension_Part (Type_Def), Derived_Type);
8858 -- Nothing else to do if there is an error in the derivation.
8859 -- An unusual case: the full view may be derived from a type in an
8860 -- instance, when the partial view was used illegally as an actual
8861 -- in that instance, leading to a circular definition.
8863 if Etype (Derived_Type) = Any_Type
8864 or else Etype (Parent_Type) = Derived_Type
8869 -- Set delayed freeze and then derive subprograms, we need to do
8870 -- this in this order so that derived subprograms inherit the
8871 -- derived freeze if necessary.
8873 Set_Has_Delayed_Freeze (Derived_Type);
8875 if Derive_Subps then
8876 Derive_Subprograms (Parent_Type, Derived_Type);
8879 -- If we have a private extension which defines a constrained derived
8880 -- type mark as constrained here after we have derived subprograms. See
8881 -- comment on point 9. just above the body of Build_Derived_Record_Type.
8883 if Private_Extension and then Inherit_Discrims then
8884 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
8885 Set_Is_Constrained (Derived_Type, True);
8886 Set_Discriminant_Constraint (Derived_Type, Discs);
8888 elsif Is_Constrained (Parent_Type) then
8890 (Derived_Type, True);
8891 Set_Discriminant_Constraint
8892 (Derived_Type, Discriminant_Constraint (Parent_Type));
8896 -- Update the class-wide type, which shares the now-completed entity
8897 -- list with its specific type. In case of underlying record views,
8898 -- we do not generate the corresponding class wide entity.
8901 and then not Is_Underlying_Record_View (Derived_Type)
8904 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
8906 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
8909 Check_Function_Writable_Actuals (N);
8910 end Build_Derived_Record_Type;
8912 ------------------------
8913 -- Build_Derived_Type --
8914 ------------------------
8916 procedure Build_Derived_Type
8918 Parent_Type : Entity_Id;
8919 Derived_Type : Entity_Id;
8920 Is_Completion : Boolean;
8921 Derive_Subps : Boolean := True)
8923 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
8926 -- Set common attributes
8928 Set_Scope (Derived_Type, Current_Scope);
8930 Set_Etype (Derived_Type, Parent_Base);
8931 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8932 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
8933 Set_Has_Protected (Derived_Type, Has_Protected (Parent_Base));
8935 Set_Size_Info (Derived_Type, Parent_Type);
8936 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
8937 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
8938 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
8939 Set_Is_Volatile (Derived_Type, Is_Volatile (Parent_Type));
8941 if Is_Tagged_Type (Derived_Type) then
8942 Set_No_Tagged_Streams_Pragma
8943 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8946 -- If the parent has primitive routines, set the derived type link
8948 if Has_Primitive_Operations (Parent_Type) then
8949 Set_Derived_Type_Link (Parent_Base, Derived_Type);
8952 -- If the parent type is a private subtype, the convention on the base
8953 -- type may be set in the private part, and not propagated to the
8954 -- subtype until later, so we obtain the convention from the base type.
8956 Set_Convention (Derived_Type, Convention (Parent_Base));
8958 -- Set SSO default for record or array type
8960 if (Is_Array_Type (Derived_Type) or else Is_Record_Type (Derived_Type))
8961 and then Is_Base_Type (Derived_Type)
8963 Set_Default_SSO (Derived_Type);
8966 -- Propagate invariant information. The new type has invariants if
8967 -- they are inherited from the parent type, and these invariants can
8968 -- be further inherited, so both flags are set.
8970 -- We similarly inherit predicates
8972 if Has_Predicates (Parent_Type) then
8973 Set_Has_Predicates (Derived_Type);
8976 -- The derived type inherits the representation clauses of the parent
8978 Inherit_Rep_Item_Chain (Derived_Type, Parent_Type);
8980 -- Propagate the attributes related to pragma Default_Initial_Condition
8981 -- from the parent type to the private extension. A derived type always
8982 -- inherits the default initial condition flag from the parent type. If
8983 -- the derived type carries its own Default_Initial_Condition pragma,
8984 -- the flag is later reset in Analyze_Pragma. Note that both flags are
8985 -- mutually exclusive.
8987 Propagate_Default_Init_Cond_Attributes
8988 (From_Typ => Parent_Type,
8989 To_Typ => Derived_Type,
8990 Parent_To_Derivation => True);
8992 -- If the parent type has delayed rep aspects, then mark the derived
8993 -- type as possibly inheriting a delayed rep aspect.
8995 if Has_Delayed_Rep_Aspects (Parent_Type) then
8996 Set_May_Inherit_Delayed_Rep_Aspects (Derived_Type);
8999 -- Propagate the attributes related to pragma Ghost from the parent type
9000 -- to the derived type or type extension (SPARK RM 6.9(9)).
9002 if Is_Ghost_Entity (Parent_Type) then
9003 Set_Is_Ghost_Entity (Derived_Type);
9006 -- Type dependent processing
9008 case Ekind (Parent_Type) is
9009 when Numeric_Kind =>
9010 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
9013 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
9017 | Class_Wide_Kind =>
9018 Build_Derived_Record_Type
9019 (N, Parent_Type, Derived_Type, Derive_Subps);
9022 when Enumeration_Kind =>
9023 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
9026 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
9028 when Incomplete_Or_Private_Kind =>
9029 Build_Derived_Private_Type
9030 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
9032 -- For discriminated types, the derivation includes deriving
9033 -- primitive operations. For others it is done below.
9035 if Is_Tagged_Type (Parent_Type)
9036 or else Has_Discriminants (Parent_Type)
9037 or else (Present (Full_View (Parent_Type))
9038 and then Has_Discriminants (Full_View (Parent_Type)))
9043 when Concurrent_Kind =>
9044 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
9047 raise Program_Error;
9050 -- Nothing more to do if some error occurred
9052 if Etype (Derived_Type) = Any_Type then
9056 -- Set delayed freeze and then derive subprograms, we need to do this
9057 -- in this order so that derived subprograms inherit the derived freeze
9060 Set_Has_Delayed_Freeze (Derived_Type);
9062 if Derive_Subps then
9063 Derive_Subprograms (Parent_Type, Derived_Type);
9066 Set_Has_Primitive_Operations
9067 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
9068 end Build_Derived_Type;
9070 -----------------------
9071 -- Build_Discriminal --
9072 -----------------------
9074 procedure Build_Discriminal (Discrim : Entity_Id) is
9075 D_Minal : Entity_Id;
9076 CR_Disc : Entity_Id;
9079 -- A discriminal has the same name as the discriminant
9081 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9083 Set_Ekind (D_Minal, E_In_Parameter);
9084 Set_Mechanism (D_Minal, Default_Mechanism);
9085 Set_Etype (D_Minal, Etype (Discrim));
9086 Set_Scope (D_Minal, Current_Scope);
9088 Set_Discriminal (Discrim, D_Minal);
9089 Set_Discriminal_Link (D_Minal, Discrim);
9091 -- For task types, build at once the discriminants of the corresponding
9092 -- record, which are needed if discriminants are used in entry defaults
9093 -- and in family bounds.
9095 if Is_Concurrent_Type (Current_Scope)
9097 Is_Limited_Type (Current_Scope)
9099 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
9101 Set_Ekind (CR_Disc, E_In_Parameter);
9102 Set_Mechanism (CR_Disc, Default_Mechanism);
9103 Set_Etype (CR_Disc, Etype (Discrim));
9104 Set_Scope (CR_Disc, Current_Scope);
9105 Set_Discriminal_Link (CR_Disc, Discrim);
9106 Set_CR_Discriminant (Discrim, CR_Disc);
9108 end Build_Discriminal;
9110 ------------------------------------
9111 -- Build_Discriminant_Constraints --
9112 ------------------------------------
9114 function Build_Discriminant_Constraints
9117 Derived_Def : Boolean := False) return Elist_Id
9119 C : constant Node_Id := Constraint (Def);
9120 Nb_Discr : constant Nat := Number_Discriminants (T);
9122 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
9123 -- Saves the expression corresponding to a given discriminant in T
9125 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
9126 -- Return the Position number within array Discr_Expr of a discriminant
9127 -- D within the discriminant list of the discriminated type T.
9129 procedure Process_Discriminant_Expression
9132 -- If this is a discriminant constraint on a partial view, do not
9133 -- generate an overflow check on the discriminant expression. The check
9134 -- will be generated when constraining the full view. Otherwise the
9135 -- backend creates duplicate symbols for the temporaries corresponding
9136 -- to the expressions to be checked, causing spurious assembler errors.
9142 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
9146 Disc := First_Discriminant (T);
9147 for J in Discr_Expr'Range loop
9152 Next_Discriminant (Disc);
9155 -- Note: Since this function is called on discriminants that are
9156 -- known to belong to the discriminated type, falling through the
9157 -- loop with no match signals an internal compiler error.
9159 raise Program_Error;
9162 -------------------------------------
9163 -- Process_Discriminant_Expression --
9164 -------------------------------------
9166 procedure Process_Discriminant_Expression
9170 BDT : constant Entity_Id := Base_Type (Etype (D));
9173 -- If this is a discriminant constraint on a partial view, do
9174 -- not generate an overflow on the discriminant expression. The
9175 -- check will be generated when constraining the full view.
9177 if Is_Private_Type (T)
9178 and then Present (Full_View (T))
9180 Analyze_And_Resolve (Expr, BDT, Suppress => Overflow_Check);
9182 Analyze_And_Resolve (Expr, BDT);
9184 end Process_Discriminant_Expression;
9186 -- Declarations local to Build_Discriminant_Constraints
9190 Elist : constant Elist_Id := New_Elmt_List;
9198 Discrim_Present : Boolean := False;
9200 -- Start of processing for Build_Discriminant_Constraints
9203 -- The following loop will process positional associations only.
9204 -- For a positional association, the (single) discriminant is
9205 -- implicitly specified by position, in textual order (RM 3.7.2).
9207 Discr := First_Discriminant (T);
9208 Constr := First (Constraints (C));
9209 for D in Discr_Expr'Range loop
9210 exit when Nkind (Constr) = N_Discriminant_Association;
9213 Error_Msg_N ("too few discriminants given in constraint", C);
9214 return New_Elmt_List;
9216 elsif Nkind (Constr) = N_Range
9217 or else (Nkind (Constr) = N_Attribute_Reference
9218 and then Attribute_Name (Constr) = Name_Range)
9221 ("a range is not a valid discriminant constraint", Constr);
9222 Discr_Expr (D) := Error;
9225 Process_Discriminant_Expression (Constr, Discr);
9226 Discr_Expr (D) := Constr;
9229 Next_Discriminant (Discr);
9233 if No (Discr) and then Present (Constr) then
9234 Error_Msg_N ("too many discriminants given in constraint", Constr);
9235 return New_Elmt_List;
9238 -- Named associations can be given in any order, but if both positional
9239 -- and named associations are used in the same discriminant constraint,
9240 -- then positional associations must occur first, at their normal
9241 -- position. Hence once a named association is used, the rest of the
9242 -- discriminant constraint must use only named associations.
9244 while Present (Constr) loop
9246 -- Positional association forbidden after a named association
9248 if Nkind (Constr) /= N_Discriminant_Association then
9249 Error_Msg_N ("positional association follows named one", Constr);
9250 return New_Elmt_List;
9252 -- Otherwise it is a named association
9255 -- E records the type of the discriminants in the named
9256 -- association. All the discriminants specified in the same name
9257 -- association must have the same type.
9261 -- Search the list of discriminants in T to see if the simple name
9262 -- given in the constraint matches any of them.
9264 Id := First (Selector_Names (Constr));
9265 while Present (Id) loop
9268 -- If Original_Discriminant is present, we are processing a
9269 -- generic instantiation and this is an instance node. We need
9270 -- to find the name of the corresponding discriminant in the
9271 -- actual record type T and not the name of the discriminant in
9272 -- the generic formal. Example:
9275 -- type G (D : int) is private;
9277 -- subtype W is G (D => 1);
9279 -- type Rec (X : int) is record ... end record;
9280 -- package Q is new P (G => Rec);
9282 -- At the point of the instantiation, formal type G is Rec
9283 -- and therefore when reanalyzing "subtype W is G (D => 1);"
9284 -- which really looks like "subtype W is Rec (D => 1);" at
9285 -- the point of instantiation, we want to find the discriminant
9286 -- that corresponds to D in Rec, i.e. X.
9288 if Present (Original_Discriminant (Id))
9289 and then In_Instance
9291 Discr := Find_Corresponding_Discriminant (Id, T);
9295 Discr := First_Discriminant (T);
9296 while Present (Discr) loop
9297 if Chars (Discr) = Chars (Id) then
9302 Next_Discriminant (Discr);
9306 Error_Msg_N ("& does not match any discriminant", Id);
9307 return New_Elmt_List;
9309 -- If the parent type is a generic formal, preserve the
9310 -- name of the discriminant for subsequent instances.
9311 -- see comment at the beginning of this if statement.
9313 elsif Is_Generic_Type (Root_Type (T)) then
9314 Set_Original_Discriminant (Id, Discr);
9318 Position := Pos_Of_Discr (T, Discr);
9320 if Present (Discr_Expr (Position)) then
9321 Error_Msg_N ("duplicate constraint for discriminant&", Id);
9324 -- Each discriminant specified in the same named association
9325 -- must be associated with a separate copy of the
9326 -- corresponding expression.
9328 if Present (Next (Id)) then
9329 Expr := New_Copy_Tree (Expression (Constr));
9330 Set_Parent (Expr, Parent (Expression (Constr)));
9332 Expr := Expression (Constr);
9335 Discr_Expr (Position) := Expr;
9336 Process_Discriminant_Expression (Expr, Discr);
9339 -- A discriminant association with more than one discriminant
9340 -- name is only allowed if the named discriminants are all of
9341 -- the same type (RM 3.7.1(8)).
9344 E := Base_Type (Etype (Discr));
9346 elsif Base_Type (Etype (Discr)) /= E then
9348 ("all discriminants in an association " &
9349 "must have the same type", Id);
9359 -- A discriminant constraint must provide exactly one value for each
9360 -- discriminant of the type (RM 3.7.1(8)).
9362 for J in Discr_Expr'Range loop
9363 if No (Discr_Expr (J)) then
9364 Error_Msg_N ("too few discriminants given in constraint", C);
9365 return New_Elmt_List;
9369 -- Determine if there are discriminant expressions in the constraint
9371 for J in Discr_Expr'Range loop
9372 if Denotes_Discriminant
9373 (Discr_Expr (J), Check_Concurrent => True)
9375 Discrim_Present := True;
9379 -- Build an element list consisting of the expressions given in the
9380 -- discriminant constraint and apply the appropriate checks. The list
9381 -- is constructed after resolving any named discriminant associations
9382 -- and therefore the expressions appear in the textual order of the
9385 Discr := First_Discriminant (T);
9386 for J in Discr_Expr'Range loop
9387 if Discr_Expr (J) /= Error then
9388 Append_Elmt (Discr_Expr (J), Elist);
9390 -- If any of the discriminant constraints is given by a
9391 -- discriminant and we are in a derived type declaration we
9392 -- have a discriminant renaming. Establish link between new
9393 -- and old discriminant.
9395 if Denotes_Discriminant (Discr_Expr (J)) then
9397 Set_Corresponding_Discriminant
9398 (Entity (Discr_Expr (J)), Discr);
9401 -- Force the evaluation of non-discriminant expressions.
9402 -- If we have found a discriminant in the constraint 3.4(26)
9403 -- and 3.8(18) demand that no range checks are performed are
9404 -- after evaluation. If the constraint is for a component
9405 -- definition that has a per-object constraint, expressions are
9406 -- evaluated but not checked either. In all other cases perform
9410 if Discrim_Present then
9413 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
9415 Has_Per_Object_Constraint
9416 (Defining_Identifier (Parent (Parent (Def))))
9420 elsif Is_Access_Type (Etype (Discr)) then
9421 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
9424 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
9427 Force_Evaluation (Discr_Expr (J));
9430 -- Check that the designated type of an access discriminant's
9431 -- expression is not a class-wide type unless the discriminant's
9432 -- designated type is also class-wide.
9434 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
9435 and then not Is_Class_Wide_Type
9436 (Designated_Type (Etype (Discr)))
9437 and then Etype (Discr_Expr (J)) /= Any_Type
9438 and then Is_Class_Wide_Type
9439 (Designated_Type (Etype (Discr_Expr (J))))
9441 Wrong_Type (Discr_Expr (J), Etype (Discr));
9443 elsif Is_Access_Type (Etype (Discr))
9444 and then not Is_Access_Constant (Etype (Discr))
9445 and then Is_Access_Type (Etype (Discr_Expr (J)))
9446 and then Is_Access_Constant (Etype (Discr_Expr (J)))
9449 ("constraint for discriminant& must be access to variable",
9454 Next_Discriminant (Discr);
9458 end Build_Discriminant_Constraints;
9460 ---------------------------------
9461 -- Build_Discriminated_Subtype --
9462 ---------------------------------
9464 procedure Build_Discriminated_Subtype
9468 Related_Nod : Node_Id;
9469 For_Access : Boolean := False)
9471 Has_Discrs : constant Boolean := Has_Discriminants (T);
9472 Constrained : constant Boolean :=
9474 and then not Is_Empty_Elmt_List (Elist)
9475 and then not Is_Class_Wide_Type (T))
9476 or else Is_Constrained (T);
9479 if Ekind (T) = E_Record_Type then
9481 Set_Ekind (Def_Id, E_Private_Subtype);
9482 Set_Is_For_Access_Subtype (Def_Id, True);
9484 Set_Ekind (Def_Id, E_Record_Subtype);
9487 -- Inherit preelaboration flag from base, for types for which it
9488 -- may have been set: records, private types, protected types.
9490 Set_Known_To_Have_Preelab_Init
9491 (Def_Id, Known_To_Have_Preelab_Init (T));
9493 elsif Ekind (T) = E_Task_Type then
9494 Set_Ekind (Def_Id, E_Task_Subtype);
9496 elsif Ekind (T) = E_Protected_Type then
9497 Set_Ekind (Def_Id, E_Protected_Subtype);
9498 Set_Known_To_Have_Preelab_Init
9499 (Def_Id, Known_To_Have_Preelab_Init (T));
9501 elsif Is_Private_Type (T) then
9502 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
9503 Set_Known_To_Have_Preelab_Init
9504 (Def_Id, Known_To_Have_Preelab_Init (T));
9506 -- Private subtypes may have private dependents
9508 Set_Private_Dependents (Def_Id, New_Elmt_List);
9510 elsif Is_Class_Wide_Type (T) then
9511 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
9514 -- Incomplete type. Attach subtype to list of dependents, to be
9515 -- completed with full view of parent type, unless is it the
9516 -- designated subtype of a record component within an init_proc.
9517 -- This last case arises for a component of an access type whose
9518 -- designated type is incomplete (e.g. a Taft Amendment type).
9519 -- The designated subtype is within an inner scope, and needs no
9520 -- elaboration, because only the access type is needed in the
9521 -- initialization procedure.
9523 Set_Ekind (Def_Id, Ekind (T));
9525 if For_Access and then Within_Init_Proc then
9528 Append_Elmt (Def_Id, Private_Dependents (T));
9532 Set_Etype (Def_Id, T);
9533 Init_Size_Align (Def_Id);
9534 Set_Has_Discriminants (Def_Id, Has_Discrs);
9535 Set_Is_Constrained (Def_Id, Constrained);
9537 Set_First_Entity (Def_Id, First_Entity (T));
9538 Set_Last_Entity (Def_Id, Last_Entity (T));
9539 Set_Has_Implicit_Dereference
9540 (Def_Id, Has_Implicit_Dereference (T));
9542 -- If the subtype is the completion of a private declaration, there may
9543 -- have been representation clauses for the partial view, and they must
9544 -- be preserved. Build_Derived_Type chains the inherited clauses with
9545 -- the ones appearing on the extension. If this comes from a subtype
9546 -- declaration, all clauses are inherited.
9548 if No (First_Rep_Item (Def_Id)) then
9549 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
9552 if Is_Tagged_Type (T) then
9553 Set_Is_Tagged_Type (Def_Id);
9554 Set_No_Tagged_Streams_Pragma (Def_Id, No_Tagged_Streams_Pragma (T));
9555 Make_Class_Wide_Type (Def_Id);
9558 Set_Stored_Constraint (Def_Id, No_Elist);
9561 Set_Discriminant_Constraint (Def_Id, Elist);
9562 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
9565 if Is_Tagged_Type (T) then
9567 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
9568 -- concurrent record type (which has the list of primitive
9571 if Ada_Version >= Ada_2005
9572 and then Is_Concurrent_Type (T)
9574 Set_Corresponding_Record_Type (Def_Id,
9575 Corresponding_Record_Type (T));
9577 Set_Direct_Primitive_Operations (Def_Id,
9578 Direct_Primitive_Operations (T));
9581 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
9584 -- Subtypes introduced by component declarations do not need to be
9585 -- marked as delayed, and do not get freeze nodes, because the semantics
9586 -- verifies that the parents of the subtypes are frozen before the
9587 -- enclosing record is frozen.
9589 if not Is_Type (Scope (Def_Id)) then
9590 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
9592 if Is_Private_Type (T)
9593 and then Present (Full_View (T))
9595 Conditional_Delay (Def_Id, Full_View (T));
9597 Conditional_Delay (Def_Id, T);
9601 if Is_Record_Type (T) then
9602 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
9605 and then not Is_Empty_Elmt_List (Elist)
9606 and then not For_Access
9608 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
9609 elsif not For_Access then
9610 Set_Cloned_Subtype (Def_Id, T);
9613 end Build_Discriminated_Subtype;
9615 ---------------------------
9616 -- Build_Itype_Reference --
9617 ---------------------------
9619 procedure Build_Itype_Reference
9623 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
9626 -- Itype references are only created for use by the back-end
9628 if Inside_A_Generic then
9631 Set_Itype (IR, Ityp);
9632 Insert_After (Nod, IR);
9634 end Build_Itype_Reference;
9636 ------------------------
9637 -- Build_Scalar_Bound --
9638 ------------------------
9640 function Build_Scalar_Bound
9643 Der_T : Entity_Id) return Node_Id
9645 New_Bound : Entity_Id;
9648 -- Note: not clear why this is needed, how can the original bound
9649 -- be unanalyzed at this point? and if it is, what business do we
9650 -- have messing around with it? and why is the base type of the
9651 -- parent type the right type for the resolution. It probably is
9652 -- not. It is OK for the new bound we are creating, but not for
9653 -- the old one??? Still if it never happens, no problem.
9655 Analyze_And_Resolve (Bound, Base_Type (Par_T));
9657 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
9658 New_Bound := New_Copy (Bound);
9659 Set_Etype (New_Bound, Der_T);
9660 Set_Analyzed (New_Bound);
9662 elsif Is_Entity_Name (Bound) then
9663 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
9665 -- The following is almost certainly wrong. What business do we have
9666 -- relocating a node (Bound) that is presumably still attached to
9667 -- the tree elsewhere???
9670 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
9673 Set_Etype (New_Bound, Der_T);
9675 end Build_Scalar_Bound;
9677 --------------------------------
9678 -- Build_Underlying_Full_View --
9679 --------------------------------
9681 procedure Build_Underlying_Full_View
9686 Loc : constant Source_Ptr := Sloc (N);
9687 Subt : constant Entity_Id :=
9688 Make_Defining_Identifier
9689 (Loc, New_External_Name (Chars (Typ), 'S'));
9696 procedure Set_Discriminant_Name (Id : Node_Id);
9697 -- If the derived type has discriminants, they may rename discriminants
9698 -- of the parent. When building the full view of the parent, we need to
9699 -- recover the names of the original discriminants if the constraint is
9700 -- given by named associations.
9702 ---------------------------
9703 -- Set_Discriminant_Name --
9704 ---------------------------
9706 procedure Set_Discriminant_Name (Id : Node_Id) is
9710 Set_Original_Discriminant (Id, Empty);
9712 if Has_Discriminants (Typ) then
9713 Disc := First_Discriminant (Typ);
9714 while Present (Disc) loop
9715 if Chars (Disc) = Chars (Id)
9716 and then Present (Corresponding_Discriminant (Disc))
9718 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
9720 Next_Discriminant (Disc);
9723 end Set_Discriminant_Name;
9725 -- Start of processing for Build_Underlying_Full_View
9728 if Nkind (N) = N_Full_Type_Declaration then
9729 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
9731 elsif Nkind (N) = N_Subtype_Declaration then
9732 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
9734 elsif Nkind (N) = N_Component_Declaration then
9737 (Constraint (Subtype_Indication (Component_Definition (N))));
9740 raise Program_Error;
9743 C := First (Constraints (Constr));
9744 while Present (C) loop
9745 if Nkind (C) = N_Discriminant_Association then
9746 Id := First (Selector_Names (C));
9747 while Present (Id) loop
9748 Set_Discriminant_Name (Id);
9757 Make_Subtype_Declaration (Loc,
9758 Defining_Identifier => Subt,
9759 Subtype_Indication =>
9760 Make_Subtype_Indication (Loc,
9761 Subtype_Mark => New_Occurrence_Of (Par, Loc),
9762 Constraint => New_Copy_Tree (Constr)));
9764 -- If this is a component subtype for an outer itype, it is not
9765 -- a list member, so simply set the parent link for analysis: if
9766 -- the enclosing type does not need to be in a declarative list,
9767 -- neither do the components.
9769 if Is_List_Member (N)
9770 and then Nkind (N) /= N_Component_Declaration
9772 Insert_Before (N, Indic);
9774 Set_Parent (Indic, Parent (N));
9778 Set_Underlying_Full_View (Typ, Full_View (Subt));
9779 end Build_Underlying_Full_View;
9781 -------------------------------
9782 -- Check_Abstract_Overriding --
9783 -------------------------------
9785 procedure Check_Abstract_Overriding (T : Entity_Id) is
9786 Alias_Subp : Entity_Id;
9792 procedure Check_Pragma_Implemented (Subp : Entity_Id);
9793 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
9794 -- which has pragma Implemented already set. Check whether Subp's entity
9795 -- kind conforms to the implementation kind of the overridden routine.
9797 procedure Check_Pragma_Implemented
9799 Iface_Subp : Entity_Id);
9800 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
9801 -- Iface_Subp and both entities have pragma Implemented already set on
9802 -- them. Check whether the two implementation kinds are conforming.
9804 procedure Inherit_Pragma_Implemented
9806 Iface_Subp : Entity_Id);
9807 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
9808 -- subprogram Iface_Subp which has been marked by pragma Implemented.
9809 -- Propagate the implementation kind of Iface_Subp to Subp.
9811 ------------------------------
9812 -- Check_Pragma_Implemented --
9813 ------------------------------
9815 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
9816 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
9817 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
9818 Subp_Alias : constant Entity_Id := Alias (Subp);
9819 Contr_Typ : Entity_Id;
9820 Impl_Subp : Entity_Id;
9823 -- Subp must have an alias since it is a hidden entity used to link
9824 -- an interface subprogram to its overriding counterpart.
9826 pragma Assert (Present (Subp_Alias));
9828 -- Handle aliases to synchronized wrappers
9830 Impl_Subp := Subp_Alias;
9832 if Is_Primitive_Wrapper (Impl_Subp) then
9833 Impl_Subp := Wrapped_Entity (Impl_Subp);
9836 -- Extract the type of the controlling formal
9838 Contr_Typ := Etype (First_Formal (Subp_Alias));
9840 if Is_Concurrent_Record_Type (Contr_Typ) then
9841 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
9844 -- An interface subprogram whose implementation kind is By_Entry must
9845 -- be implemented by an entry.
9847 if Impl_Kind = Name_By_Entry
9848 and then Ekind (Impl_Subp) /= E_Entry
9850 Error_Msg_Node_2 := Iface_Alias;
9852 ("type & must implement abstract subprogram & with an entry",
9853 Subp_Alias, Contr_Typ);
9855 elsif Impl_Kind = Name_By_Protected_Procedure then
9857 -- An interface subprogram whose implementation kind is By_
9858 -- Protected_Procedure cannot be implemented by a primitive
9859 -- procedure of a task type.
9861 if Ekind (Contr_Typ) /= E_Protected_Type then
9862 Error_Msg_Node_2 := Contr_Typ;
9864 ("interface subprogram & cannot be implemented by a " &
9865 "primitive procedure of task type &", Subp_Alias,
9868 -- An interface subprogram whose implementation kind is By_
9869 -- Protected_Procedure must be implemented by a procedure.
9871 elsif Ekind (Impl_Subp) /= E_Procedure then
9872 Error_Msg_Node_2 := Iface_Alias;
9874 ("type & must implement abstract subprogram & with a " &
9875 "procedure", Subp_Alias, Contr_Typ);
9877 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9878 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9880 Error_Msg_Name_1 := Impl_Kind;
9882 ("overriding operation& must have synchronization%",
9886 -- If primitive has Optional synchronization, overriding operation
9887 -- must match if it has an explicit synchronization..
9889 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9890 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9892 Error_Msg_Name_1 := Impl_Kind;
9894 ("overriding operation& must have syncrhonization%",
9897 end Check_Pragma_Implemented;
9899 ------------------------------
9900 -- Check_Pragma_Implemented --
9901 ------------------------------
9903 procedure Check_Pragma_Implemented
9905 Iface_Subp : Entity_Id)
9907 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9908 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
9911 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
9912 -- and overriding subprogram are different. In general this is an
9913 -- error except when the implementation kind of the overridden
9914 -- subprograms is By_Any or Optional.
9916 if Iface_Kind /= Subp_Kind
9917 and then Iface_Kind /= Name_By_Any
9918 and then Iface_Kind /= Name_Optional
9920 if Iface_Kind = Name_By_Entry then
9922 ("incompatible implementation kind, overridden subprogram " &
9923 "is marked By_Entry", Subp);
9926 ("incompatible implementation kind, overridden subprogram " &
9927 "is marked By_Protected_Procedure", Subp);
9930 end Check_Pragma_Implemented;
9932 --------------------------------
9933 -- Inherit_Pragma_Implemented --
9934 --------------------------------
9936 procedure Inherit_Pragma_Implemented
9938 Iface_Subp : Entity_Id)
9940 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9941 Loc : constant Source_Ptr := Sloc (Subp);
9942 Impl_Prag : Node_Id;
9945 -- Since the implementation kind is stored as a representation item
9946 -- rather than a flag, create a pragma node.
9950 Chars => Name_Implemented,
9951 Pragma_Argument_Associations => New_List (
9952 Make_Pragma_Argument_Association (Loc,
9953 Expression => New_Occurrence_Of (Subp, Loc)),
9955 Make_Pragma_Argument_Association (Loc,
9956 Expression => Make_Identifier (Loc, Iface_Kind))));
9958 -- The pragma doesn't need to be analyzed because it is internally
9959 -- built. It is safe to directly register it as a rep item since we
9960 -- are only interested in the characters of the implementation kind.
9962 Record_Rep_Item (Subp, Impl_Prag);
9963 end Inherit_Pragma_Implemented;
9965 -- Start of processing for Check_Abstract_Overriding
9968 Op_List := Primitive_Operations (T);
9970 -- Loop to check primitive operations
9972 Elmt := First_Elmt (Op_List);
9973 while Present (Elmt) loop
9974 Subp := Node (Elmt);
9975 Alias_Subp := Alias (Subp);
9977 -- Inherited subprograms are identified by the fact that they do not
9978 -- come from source, and the associated source location is the
9979 -- location of the first subtype of the derived type.
9981 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
9982 -- subprograms that "require overriding".
9984 -- Special exception, do not complain about failure to override the
9985 -- stream routines _Input and _Output, as well as the primitive
9986 -- operations used in dispatching selects since we always provide
9987 -- automatic overridings for these subprograms.
9989 -- Also ignore this rule for convention CIL since .NET libraries
9990 -- do bizarre things with interfaces???
9992 -- The partial view of T may have been a private extension, for
9993 -- which inherited functions dispatching on result are abstract.
9994 -- If the full view is a null extension, there is no need for
9995 -- overriding in Ada 2005, but wrappers need to be built for them
9996 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
9998 if Is_Null_Extension (T)
9999 and then Has_Controlling_Result (Subp)
10000 and then Ada_Version >= Ada_2005
10001 and then Present (Alias_Subp)
10002 and then not Comes_From_Source (Subp)
10003 and then not Is_Abstract_Subprogram (Alias_Subp)
10004 and then not Is_Access_Type (Etype (Subp))
10008 -- Ada 2005 (AI-251): Internal entities of interfaces need no
10009 -- processing because this check is done with the aliased
10012 elsif Present (Interface_Alias (Subp)) then
10015 elsif (Is_Abstract_Subprogram (Subp)
10016 or else Requires_Overriding (Subp)
10018 (Has_Controlling_Result (Subp)
10019 and then Present (Alias_Subp)
10020 and then not Comes_From_Source (Subp)
10021 and then Sloc (Subp) = Sloc (First_Subtype (T))))
10022 and then not Is_TSS (Subp, TSS_Stream_Input)
10023 and then not Is_TSS (Subp, TSS_Stream_Output)
10024 and then not Is_Abstract_Type (T)
10025 and then Convention (T) /= Convention_CIL
10026 and then not Is_Predefined_Interface_Primitive (Subp)
10028 -- Ada 2005 (AI-251): Do not consider hidden entities associated
10029 -- with abstract interface types because the check will be done
10030 -- with the aliased entity (otherwise we generate a duplicated
10033 and then not Present (Interface_Alias (Subp))
10035 if Present (Alias_Subp) then
10037 -- Only perform the check for a derived subprogram when the
10038 -- type has an explicit record extension. This avoids incorrect
10039 -- flagging of abstract subprograms for the case of a type
10040 -- without an extension that is derived from a formal type
10041 -- with a tagged actual (can occur within a private part).
10043 -- Ada 2005 (AI-391): In the case of an inherited function with
10044 -- a controlling result of the type, the rule does not apply if
10045 -- the type is a null extension (unless the parent function
10046 -- itself is abstract, in which case the function must still be
10047 -- be overridden). The expander will generate an overriding
10048 -- wrapper function calling the parent subprogram (see
10049 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
10051 Type_Def := Type_Definition (Parent (T));
10053 if Nkind (Type_Def) = N_Derived_Type_Definition
10054 and then Present (Record_Extension_Part (Type_Def))
10056 (Ada_Version < Ada_2005
10057 or else not Is_Null_Extension (T)
10058 or else Ekind (Subp) = E_Procedure
10059 or else not Has_Controlling_Result (Subp)
10060 or else Is_Abstract_Subprogram (Alias_Subp)
10061 or else Requires_Overriding (Subp)
10062 or else Is_Access_Type (Etype (Subp)))
10064 -- Avoid reporting error in case of abstract predefined
10065 -- primitive inherited from interface type because the
10066 -- body of internally generated predefined primitives
10067 -- of tagged types are generated later by Freeze_Type
10069 if Is_Interface (Root_Type (T))
10070 and then Is_Abstract_Subprogram (Subp)
10071 and then Is_Predefined_Dispatching_Operation (Subp)
10072 and then not Comes_From_Source (Ultimate_Alias (Subp))
10076 -- A null extension is not obliged to override an inherited
10077 -- procedure subject to pragma Extensions_Visible with value
10078 -- False and at least one controlling OUT parameter
10079 -- (SPARK RM 6.1.7(6)).
10081 elsif Is_Null_Extension (T)
10082 and then Is_EVF_Procedure (Subp)
10088 ("type must be declared abstract or & overridden",
10091 -- Traverse the whole chain of aliased subprograms to
10092 -- complete the error notification. This is especially
10093 -- useful for traceability of the chain of entities when
10094 -- the subprogram corresponds with an interface
10095 -- subprogram (which may be defined in another package).
10097 if Present (Alias_Subp) then
10103 while Present (Alias (E)) loop
10105 -- Avoid reporting redundant errors on entities
10106 -- inherited from interfaces
10108 if Sloc (E) /= Sloc (T) then
10109 Error_Msg_Sloc := Sloc (E);
10111 ("\& has been inherited #", T, Subp);
10117 Error_Msg_Sloc := Sloc (E);
10119 -- AI05-0068: report if there is an overriding
10120 -- non-abstract subprogram that is invisible.
10123 and then not Is_Abstract_Subprogram (E)
10126 ("\& subprogram# is not visible",
10129 -- Clarify the case where a non-null extension must
10130 -- override inherited procedure subject to pragma
10131 -- Extensions_Visible with value False and at least
10132 -- one controlling OUT param.
10134 elsif Is_EVF_Procedure (E) then
10136 ("\& # is subject to Extensions_Visible False",
10141 ("\& has been inherited from subprogram #",
10148 -- Ada 2005 (AI-345): Protected or task type implementing
10149 -- abstract interfaces.
10151 elsif Is_Concurrent_Record_Type (T)
10152 and then Present (Interfaces (T))
10154 -- There is no need to check here RM 9.4(11.9/3) since we
10155 -- are processing the corresponding record type and the
10156 -- mode of the overriding subprograms was verified by
10157 -- Check_Conformance when the corresponding concurrent
10158 -- type declaration was analyzed.
10161 ("interface subprogram & must be overridden", T, Subp);
10163 -- Examine primitive operations of synchronized type to find
10164 -- homonyms that have the wrong profile.
10170 Prim := First_Entity (Corresponding_Concurrent_Type (T));
10171 while Present (Prim) loop
10172 if Chars (Prim) = Chars (Subp) then
10174 ("profile is not type conformant with prefixed "
10175 & "view profile of inherited operation&",
10179 Next_Entity (Prim);
10185 Error_Msg_Node_2 := T;
10187 ("abstract subprogram& not allowed for type&", Subp);
10189 -- Also post unconditional warning on the type (unconditional
10190 -- so that if there are more than one of these cases, we get
10191 -- them all, and not just the first one).
10193 Error_Msg_Node_2 := Subp;
10194 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
10197 -- A subprogram subject to pragma Extensions_Visible with value
10198 -- "True" cannot override a subprogram subject to the same pragma
10199 -- with value "False" (SPARK RM 6.1.7(5)).
10201 elsif Extensions_Visible_Status (Subp) = Extensions_Visible_True
10202 and then Present (Overridden_Operation (Subp))
10203 and then Extensions_Visible_Status (Overridden_Operation (Subp)) =
10204 Extensions_Visible_False
10206 Error_Msg_Sloc := Sloc (Overridden_Operation (Subp));
10208 ("subprogram & with Extensions_Visible True cannot override "
10209 & "subprogram # with Extensions_Visible False", Subp);
10212 -- Ada 2012 (AI05-0030): Perform checks related to pragma Implemented
10214 -- Subp is an expander-generated procedure which maps an interface
10215 -- alias to a protected wrapper. The interface alias is flagged by
10216 -- pragma Implemented. Ensure that Subp is a procedure when the
10217 -- implementation kind is By_Protected_Procedure or an entry when
10220 if Ada_Version >= Ada_2012
10221 and then Is_Hidden (Subp)
10222 and then Present (Interface_Alias (Subp))
10223 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
10225 Check_Pragma_Implemented (Subp);
10228 -- Subp is an interface primitive which overrides another interface
10229 -- primitive marked with pragma Implemented.
10231 if Ada_Version >= Ada_2012
10232 and then Present (Overridden_Operation (Subp))
10233 and then Has_Rep_Pragma
10234 (Overridden_Operation (Subp), Name_Implemented)
10236 -- If the overriding routine is also marked by Implemented, check
10237 -- that the two implementation kinds are conforming.
10239 if Has_Rep_Pragma (Subp, Name_Implemented) then
10240 Check_Pragma_Implemented
10242 Iface_Subp => Overridden_Operation (Subp));
10244 -- Otherwise the overriding routine inherits the implementation
10245 -- kind from the overridden subprogram.
10248 Inherit_Pragma_Implemented
10250 Iface_Subp => Overridden_Operation (Subp));
10254 -- If the operation is a wrapper for a synchronized primitive, it
10255 -- may be called indirectly through a dispatching select. We assume
10256 -- that it will be referenced elsewhere indirectly, and suppress
10257 -- warnings about an unused entity.
10259 if Is_Primitive_Wrapper (Subp)
10260 and then Present (Wrapped_Entity (Subp))
10262 Set_Referenced (Wrapped_Entity (Subp));
10267 end Check_Abstract_Overriding;
10269 ------------------------------------------------
10270 -- Check_Access_Discriminant_Requires_Limited --
10271 ------------------------------------------------
10273 procedure Check_Access_Discriminant_Requires_Limited
10278 -- A discriminant_specification for an access discriminant shall appear
10279 -- only in the declaration for a task or protected type, or for a type
10280 -- with the reserved word 'limited' in its definition or in one of its
10281 -- ancestors (RM 3.7(10)).
10283 -- AI-0063: The proper condition is that type must be immutably limited,
10284 -- or else be a partial view.
10286 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
10287 if Is_Limited_View (Current_Scope)
10289 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
10290 and then Limited_Present (Parent (Current_Scope)))
10296 ("access discriminants allowed only for limited types", Loc);
10299 end Check_Access_Discriminant_Requires_Limited;
10301 -----------------------------------
10302 -- Check_Aliased_Component_Types --
10303 -----------------------------------
10305 procedure Check_Aliased_Component_Types (T : Entity_Id) is
10309 -- ??? Also need to check components of record extensions, but not
10310 -- components of protected types (which are always limited).
10312 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
10313 -- types to be unconstrained. This is safe because it is illegal to
10314 -- create access subtypes to such types with explicit discriminant
10317 if not Is_Limited_Type (T) then
10318 if Ekind (T) = E_Record_Type then
10319 C := First_Component (T);
10320 while Present (C) loop
10322 and then Has_Discriminants (Etype (C))
10323 and then not Is_Constrained (Etype (C))
10324 and then not In_Instance_Body
10325 and then Ada_Version < Ada_2005
10328 ("aliased component must be constrained (RM 3.6(11))",
10332 Next_Component (C);
10335 elsif Ekind (T) = E_Array_Type then
10336 if Has_Aliased_Components (T)
10337 and then Has_Discriminants (Component_Type (T))
10338 and then not Is_Constrained (Component_Type (T))
10339 and then not In_Instance_Body
10340 and then Ada_Version < Ada_2005
10343 ("aliased component type must be constrained (RM 3.6(11))",
10348 end Check_Aliased_Component_Types;
10350 ---------------------------------------
10351 -- Check_Anonymous_Access_Components --
10352 ---------------------------------------
10354 procedure Check_Anonymous_Access_Components
10355 (Typ_Decl : Node_Id;
10358 Comp_List : Node_Id)
10360 Loc : constant Source_Ptr := Sloc (Typ_Decl);
10361 Anon_Access : Entity_Id;
10364 Comp_Def : Node_Id;
10366 Type_Def : Node_Id;
10368 procedure Build_Incomplete_Type_Declaration;
10369 -- If the record type contains components that include an access to the
10370 -- current record, then create an incomplete type declaration for the
10371 -- record, to be used as the designated type of the anonymous access.
10372 -- This is done only once, and only if there is no previous partial
10373 -- view of the type.
10375 function Designates_T (Subt : Node_Id) return Boolean;
10376 -- Check whether a node designates the enclosing record type, or 'Class
10379 function Mentions_T (Acc_Def : Node_Id) return Boolean;
10380 -- Check whether an access definition includes a reference to
10381 -- the enclosing record type. The reference can be a subtype mark
10382 -- in the access definition itself, a 'Class attribute reference, or
10383 -- recursively a reference appearing in a parameter specification
10384 -- or result definition of an access_to_subprogram definition.
10386 --------------------------------------
10387 -- Build_Incomplete_Type_Declaration --
10388 --------------------------------------
10390 procedure Build_Incomplete_Type_Declaration is
10395 -- Is_Tagged indicates whether the type is tagged. It is tagged if
10396 -- it's "is new ... with record" or else "is tagged record ...".
10398 Is_Tagged : constant Boolean :=
10399 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
10401 Present (Record_Extension_Part (Type_Definition (Typ_Decl))))
10403 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
10404 and then Tagged_Present (Type_Definition (Typ_Decl)));
10407 -- If there is a previous partial view, no need to create a new one
10408 -- If the partial view, given by Prev, is incomplete, If Prev is
10409 -- a private declaration, full declaration is flagged accordingly.
10411 if Prev /= Typ then
10413 Make_Class_Wide_Type (Prev);
10414 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
10415 Set_Etype (Class_Wide_Type (Typ), Typ);
10420 elsif Has_Private_Declaration (Typ) then
10422 -- If we refer to T'Class inside T, and T is the completion of a
10423 -- private type, then make sure the class-wide type exists.
10426 Make_Class_Wide_Type (Typ);
10431 -- If there was a previous anonymous access type, the incomplete
10432 -- type declaration will have been created already.
10434 elsif Present (Current_Entity (Typ))
10435 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
10436 and then Full_View (Current_Entity (Typ)) = Typ
10439 and then Comes_From_Source (Current_Entity (Typ))
10440 and then not Is_Tagged_Type (Current_Entity (Typ))
10442 Make_Class_Wide_Type (Typ);
10444 ("incomplete view of tagged type should be declared tagged??",
10445 Parent (Current_Entity (Typ)));
10450 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
10451 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
10453 -- Type has already been inserted into the current scope. Remove
10454 -- it, and add incomplete declaration for type, so that subsequent
10455 -- anonymous access types can use it. The entity is unchained from
10456 -- the homonym list and from immediate visibility. After analysis,
10457 -- the entity in the incomplete declaration becomes immediately
10458 -- visible in the record declaration that follows.
10460 H := Current_Entity (Typ);
10463 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
10466 and then Homonym (H) /= Typ
10468 H := Homonym (Typ);
10471 Set_Homonym (H, Homonym (Typ));
10474 Insert_Before (Typ_Decl, Decl);
10476 Set_Full_View (Inc_T, Typ);
10480 -- Create a common class-wide type for both views, and set the
10481 -- Etype of the class-wide type to the full view.
10483 Make_Class_Wide_Type (Inc_T);
10484 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
10485 Set_Etype (Class_Wide_Type (Typ), Typ);
10488 end Build_Incomplete_Type_Declaration;
10494 function Designates_T (Subt : Node_Id) return Boolean is
10495 Type_Id : constant Name_Id := Chars (Typ);
10497 function Names_T (Nam : Node_Id) return Boolean;
10498 -- The record type has not been introduced in the current scope
10499 -- yet, so we must examine the name of the type itself, either
10500 -- an identifier T, or an expanded name of the form P.T, where
10501 -- P denotes the current scope.
10507 function Names_T (Nam : Node_Id) return Boolean is
10509 if Nkind (Nam) = N_Identifier then
10510 return Chars (Nam) = Type_Id;
10512 elsif Nkind (Nam) = N_Selected_Component then
10513 if Chars (Selector_Name (Nam)) = Type_Id then
10514 if Nkind (Prefix (Nam)) = N_Identifier then
10515 return Chars (Prefix (Nam)) = Chars (Current_Scope);
10517 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
10518 return Chars (Selector_Name (Prefix (Nam))) =
10519 Chars (Current_Scope);
10533 -- Start of processing for Designates_T
10536 if Nkind (Subt) = N_Identifier then
10537 return Chars (Subt) = Type_Id;
10539 -- Reference can be through an expanded name which has not been
10540 -- analyzed yet, and which designates enclosing scopes.
10542 elsif Nkind (Subt) = N_Selected_Component then
10543 if Names_T (Subt) then
10546 -- Otherwise it must denote an entity that is already visible.
10547 -- The access definition may name a subtype of the enclosing
10548 -- type, if there is a previous incomplete declaration for it.
10551 Find_Selected_Component (Subt);
10553 Is_Entity_Name (Subt)
10554 and then Scope (Entity (Subt)) = Current_Scope
10556 (Chars (Base_Type (Entity (Subt))) = Type_Id
10558 (Is_Class_Wide_Type (Entity (Subt))
10560 Chars (Etype (Base_Type (Entity (Subt)))) =
10564 -- A reference to the current type may appear as the prefix of
10565 -- a 'Class attribute.
10567 elsif Nkind (Subt) = N_Attribute_Reference
10568 and then Attribute_Name (Subt) = Name_Class
10570 return Names_T (Prefix (Subt));
10581 function Mentions_T (Acc_Def : Node_Id) return Boolean is
10582 Param_Spec : Node_Id;
10584 Acc_Subprg : constant Node_Id :=
10585 Access_To_Subprogram_Definition (Acc_Def);
10588 if No (Acc_Subprg) then
10589 return Designates_T (Subtype_Mark (Acc_Def));
10592 -- Component is an access_to_subprogram: examine its formals,
10593 -- and result definition in the case of an access_to_function.
10595 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
10596 while Present (Param_Spec) loop
10597 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
10598 and then Mentions_T (Parameter_Type (Param_Spec))
10602 elsif Designates_T (Parameter_Type (Param_Spec)) then
10609 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
10610 if Nkind (Result_Definition (Acc_Subprg)) =
10611 N_Access_Definition
10613 return Mentions_T (Result_Definition (Acc_Subprg));
10615 return Designates_T (Result_Definition (Acc_Subprg));
10622 -- Start of processing for Check_Anonymous_Access_Components
10625 if No (Comp_List) then
10629 Comp := First (Component_Items (Comp_List));
10630 while Present (Comp) loop
10631 if Nkind (Comp) = N_Component_Declaration
10633 (Access_Definition (Component_Definition (Comp)))
10635 Mentions_T (Access_Definition (Component_Definition (Comp)))
10637 Comp_Def := Component_Definition (Comp);
10639 Access_To_Subprogram_Definition (Access_Definition (Comp_Def));
10641 Build_Incomplete_Type_Declaration;
10642 Anon_Access := Make_Temporary (Loc, 'S');
10644 -- Create a declaration for the anonymous access type: either
10645 -- an access_to_object or an access_to_subprogram.
10647 if Present (Acc_Def) then
10648 if Nkind (Acc_Def) = N_Access_Function_Definition then
10650 Make_Access_Function_Definition (Loc,
10651 Parameter_Specifications =>
10652 Parameter_Specifications (Acc_Def),
10653 Result_Definition => Result_Definition (Acc_Def));
10656 Make_Access_Procedure_Definition (Loc,
10657 Parameter_Specifications =>
10658 Parameter_Specifications (Acc_Def));
10663 Make_Access_To_Object_Definition (Loc,
10664 Subtype_Indication =>
10666 (Subtype_Mark (Access_Definition (Comp_Def))));
10668 Set_Constant_Present
10669 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
10671 (Type_Def, All_Present (Access_Definition (Comp_Def)));
10674 Set_Null_Exclusion_Present
10676 Null_Exclusion_Present (Access_Definition (Comp_Def)));
10679 Make_Full_Type_Declaration (Loc,
10680 Defining_Identifier => Anon_Access,
10681 Type_Definition => Type_Def);
10683 Insert_Before (Typ_Decl, Decl);
10686 -- If an access to subprogram, create the extra formals
10688 if Present (Acc_Def) then
10689 Create_Extra_Formals (Designated_Type (Anon_Access));
10691 -- If an access to object, preserve entity of designated type,
10692 -- for ASIS use, before rewriting the component definition.
10699 Desig := Entity (Subtype_Indication (Type_Def));
10701 -- If the access definition is to the current record,
10702 -- the visible entity at this point is an incomplete
10703 -- type. Retrieve the full view to simplify ASIS queries
10705 if Ekind (Desig) = E_Incomplete_Type then
10706 Desig := Full_View (Desig);
10710 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
10715 Make_Component_Definition (Loc,
10716 Subtype_Indication =>
10717 New_Occurrence_Of (Anon_Access, Loc)));
10719 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
10720 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
10722 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
10725 Set_Is_Local_Anonymous_Access (Anon_Access);
10731 if Present (Variant_Part (Comp_List)) then
10735 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
10736 while Present (V) loop
10737 Check_Anonymous_Access_Components
10738 (Typ_Decl, Typ, Prev, Component_List (V));
10739 Next_Non_Pragma (V);
10743 end Check_Anonymous_Access_Components;
10745 ----------------------
10746 -- Check_Completion --
10747 ----------------------
10749 procedure Check_Completion (Body_Id : Node_Id := Empty) is
10752 procedure Post_Error;
10753 -- Post error message for lack of completion for entity E
10759 procedure Post_Error is
10761 procedure Missing_Body;
10762 -- Output missing body message
10768 procedure Missing_Body is
10770 -- Spec is in same unit, so we can post on spec
10772 if In_Same_Source_Unit (Body_Id, E) then
10773 Error_Msg_N ("missing body for &", E);
10775 -- Spec is in a separate unit, so we have to post on the body
10778 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
10782 -- Start of processing for Post_Error
10785 if not Comes_From_Source (E) then
10787 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
10789 -- It may be an anonymous protected type created for a
10790 -- single variable. Post error on variable, if present.
10796 Var := First_Entity (Current_Scope);
10797 while Present (Var) loop
10798 exit when Etype (Var) = E
10799 and then Comes_From_Source (Var);
10804 if Present (Var) then
10811 -- If a generated entity has no completion, then either previous
10812 -- semantic errors have disabled the expansion phase, or else we had
10813 -- missing subunits, or else we are compiling without expansion,
10814 -- or else something is very wrong.
10816 if not Comes_From_Source (E) then
10818 (Serious_Errors_Detected > 0
10819 or else Configurable_Run_Time_Violations > 0
10820 or else Subunits_Missing
10821 or else not Expander_Active);
10824 -- Here for source entity
10827 -- Here if no body to post the error message, so we post the error
10828 -- on the declaration that has no completion. This is not really
10829 -- the right place to post it, think about this later ???
10831 if No (Body_Id) then
10832 if Is_Type (E) then
10834 ("missing full declaration for }", Parent (E), E);
10836 Error_Msg_NE ("missing body for &", Parent (E), E);
10839 -- Package body has no completion for a declaration that appears
10840 -- in the corresponding spec. Post error on the body, with a
10841 -- reference to the non-completed declaration.
10844 Error_Msg_Sloc := Sloc (E);
10846 if Is_Type (E) then
10847 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
10849 elsif Is_Overloadable (E)
10850 and then Current_Entity_In_Scope (E) /= E
10852 -- It may be that the completion is mistyped and appears as
10853 -- a distinct overloading of the entity.
10856 Candidate : constant Entity_Id :=
10857 Current_Entity_In_Scope (E);
10858 Decl : constant Node_Id :=
10859 Unit_Declaration_Node (Candidate);
10862 if Is_Overloadable (Candidate)
10863 and then Ekind (Candidate) = Ekind (E)
10864 and then Nkind (Decl) = N_Subprogram_Body
10865 and then Acts_As_Spec (Decl)
10867 Check_Type_Conformant (Candidate, E);
10883 Pack_Id : constant Entity_Id := Current_Scope;
10885 -- Start of processing for Check_Completion
10888 E := First_Entity (Pack_Id);
10889 while Present (E) loop
10890 if Is_Intrinsic_Subprogram (E) then
10893 -- A Ghost entity declared in a non-Ghost package does not force the
10894 -- need for a body (SPARK RM 6.9(11)).
10896 elsif not Is_Ghost_Entity (Pack_Id) and then Is_Ghost_Entity (E) then
10899 -- The following situation requires special handling: a child unit
10900 -- that appears in the context clause of the body of its parent:
10902 -- procedure Parent.Child (...);
10904 -- with Parent.Child;
10905 -- package body Parent is
10907 -- Here Parent.Child appears as a local entity, but should not be
10908 -- flagged as requiring completion, because it is a compilation
10911 -- Ignore missing completion for a subprogram that does not come from
10912 -- source (including the _Call primitive operation of RAS types,
10913 -- which has to have the flag Comes_From_Source for other purposes):
10914 -- we assume that the expander will provide the missing completion.
10915 -- In case of previous errors, other expansion actions that provide
10916 -- bodies for null procedures with not be invoked, so inhibit message
10919 -- Note that E_Operator is not in the list that follows, because
10920 -- this kind is reserved for predefined operators, that are
10921 -- intrinsic and do not need completion.
10923 elsif Ekind_In (E, E_Function,
10925 E_Generic_Function,
10926 E_Generic_Procedure)
10928 if Has_Completion (E) then
10931 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
10934 elsif Is_Subprogram (E)
10935 and then (not Comes_From_Source (E)
10936 or else Chars (E) = Name_uCall)
10941 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
10945 elsif Nkind (Parent (E)) = N_Procedure_Specification
10946 and then Null_Present (Parent (E))
10947 and then Serious_Errors_Detected > 0
10955 elsif Is_Entry (E) then
10956 if not Has_Completion (E) and then
10957 (Ekind (Scope (E)) = E_Protected_Object
10958 or else Ekind (Scope (E)) = E_Protected_Type)
10963 elsif Is_Package_Or_Generic_Package (E) then
10964 if Unit_Requires_Body (E) then
10965 if not Has_Completion (E)
10966 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
10972 elsif not Is_Child_Unit (E) then
10973 May_Need_Implicit_Body (E);
10976 -- A formal incomplete type (Ada 2012) does not require a completion;
10977 -- other incomplete type declarations do.
10979 elsif Ekind (E) = E_Incomplete_Type
10980 and then No (Underlying_Type (E))
10981 and then not Is_Generic_Type (E)
10985 elsif Ekind_In (E, E_Task_Type, E_Protected_Type)
10986 and then not Has_Completion (E)
10990 -- A single task declared in the current scope is a constant, verify
10991 -- that the body of its anonymous type is in the same scope. If the
10992 -- task is defined elsewhere, this may be a renaming declaration for
10993 -- which no completion is needed.
10995 elsif Ekind (E) = E_Constant
10996 and then Ekind (Etype (E)) = E_Task_Type
10997 and then not Has_Completion (Etype (E))
10998 and then Scope (Etype (E)) = Current_Scope
11002 elsif Ekind (E) = E_Protected_Object
11003 and then not Has_Completion (Etype (E))
11007 elsif Ekind (E) = E_Record_Type then
11008 if Is_Tagged_Type (E) then
11009 Check_Abstract_Overriding (E);
11010 Check_Conventions (E);
11013 Check_Aliased_Component_Types (E);
11015 elsif Ekind (E) = E_Array_Type then
11016 Check_Aliased_Component_Types (E);
11022 end Check_Completion;
11024 ------------------------------------
11025 -- Check_CPP_Type_Has_No_Defaults --
11026 ------------------------------------
11028 procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id) is
11029 Tdef : constant Node_Id := Type_Definition (Declaration_Node (T));
11034 -- Obtain the component list
11036 if Nkind (Tdef) = N_Record_Definition then
11037 Clist := Component_List (Tdef);
11038 else pragma Assert (Nkind (Tdef) = N_Derived_Type_Definition);
11039 Clist := Component_List (Record_Extension_Part (Tdef));
11042 -- Check all components to ensure no default expressions
11044 if Present (Clist) then
11045 Comp := First (Component_Items (Clist));
11046 while Present (Comp) loop
11047 if Present (Expression (Comp)) then
11049 ("component of imported 'C'P'P type cannot have "
11050 & "default expression", Expression (Comp));
11056 end Check_CPP_Type_Has_No_Defaults;
11058 ----------------------------
11059 -- Check_Delta_Expression --
11060 ----------------------------
11062 procedure Check_Delta_Expression (E : Node_Id) is
11064 if not (Is_Real_Type (Etype (E))) then
11065 Wrong_Type (E, Any_Real);
11067 elsif not Is_OK_Static_Expression (E) then
11068 Flag_Non_Static_Expr
11069 ("non-static expression used for delta value!", E);
11071 elsif not UR_Is_Positive (Expr_Value_R (E)) then
11072 Error_Msg_N ("delta expression must be positive", E);
11078 -- If any of above errors occurred, then replace the incorrect
11079 -- expression by the real 0.1, which should prevent further errors.
11082 Make_Real_Literal (Sloc (E), Ureal_Tenth));
11083 Analyze_And_Resolve (E, Standard_Float);
11084 end Check_Delta_Expression;
11086 -----------------------------
11087 -- Check_Digits_Expression --
11088 -----------------------------
11090 procedure Check_Digits_Expression (E : Node_Id) is
11092 if not (Is_Integer_Type (Etype (E))) then
11093 Wrong_Type (E, Any_Integer);
11095 elsif not Is_OK_Static_Expression (E) then
11096 Flag_Non_Static_Expr
11097 ("non-static expression used for digits value!", E);
11099 elsif Expr_Value (E) <= 0 then
11100 Error_Msg_N ("digits value must be greater than zero", E);
11106 -- If any of above errors occurred, then replace the incorrect
11107 -- expression by the integer 1, which should prevent further errors.
11109 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
11110 Analyze_And_Resolve (E, Standard_Integer);
11112 end Check_Digits_Expression;
11114 --------------------------
11115 -- Check_Initialization --
11116 --------------------------
11118 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
11120 -- Special processing for limited types
11122 if Is_Limited_Type (T)
11123 and then not In_Instance
11124 and then not In_Inlined_Body
11126 if not OK_For_Limited_Init (T, Exp) then
11128 -- In GNAT mode, this is just a warning, to allow it to be evilly
11129 -- turned off. Otherwise it is a real error.
11133 ("??cannot initialize entities of limited type!", Exp);
11135 elsif Ada_Version < Ada_2005 then
11137 -- The side effect removal machinery may generate illegal Ada
11138 -- code to avoid the usage of access types and 'reference in
11139 -- SPARK mode. Since this is legal code with respect to theorem
11140 -- proving, do not emit the error.
11143 and then Nkind (Exp) = N_Function_Call
11144 and then Nkind (Parent (Exp)) = N_Object_Declaration
11145 and then not Comes_From_Source
11146 (Defining_Identifier (Parent (Exp)))
11152 ("cannot initialize entities of limited type", Exp);
11153 Explain_Limited_Type (T, Exp);
11157 -- Specialize error message according to kind of illegal
11158 -- initial expression.
11160 if Nkind (Exp) = N_Type_Conversion
11161 and then Nkind (Expression (Exp)) = N_Function_Call
11164 ("illegal context for call"
11165 & " to function with limited result", Exp);
11169 ("initialization of limited object requires aggregate "
11170 & "or function call", Exp);
11176 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag gets
11177 -- set unless we can be sure that no range check is required.
11179 if (GNATprove_Mode or not Expander_Active)
11180 and then Is_Scalar_Type (T)
11181 and then not Is_In_Range (Exp, T, Assume_Valid => True)
11183 Set_Do_Range_Check (Exp);
11185 end Check_Initialization;
11187 ----------------------
11188 -- Check_Interfaces --
11189 ----------------------
11191 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
11192 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
11195 Iface_Def : Node_Id;
11196 Iface_Typ : Entity_Id;
11197 Parent_Node : Node_Id;
11199 Is_Task : Boolean := False;
11200 -- Set True if parent type or any progenitor is a task interface
11202 Is_Protected : Boolean := False;
11203 -- Set True if parent type or any progenitor is a protected interface
11205 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
11206 -- Check that a progenitor is compatible with declaration. If an error
11207 -- message is output, it is posted on Error_Node.
11213 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
11214 Iface_Id : constant Entity_Id :=
11215 Defining_Identifier (Parent (Iface_Def));
11216 Type_Def : Node_Id;
11219 if Nkind (N) = N_Private_Extension_Declaration then
11222 Type_Def := Type_Definition (N);
11225 if Is_Task_Interface (Iface_Id) then
11228 elsif Is_Protected_Interface (Iface_Id) then
11229 Is_Protected := True;
11232 if Is_Synchronized_Interface (Iface_Id) then
11234 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
11235 -- extension derived from a synchronized interface must explicitly
11236 -- be declared synchronized, because the full view will be a
11237 -- synchronized type.
11239 if Nkind (N) = N_Private_Extension_Declaration then
11240 if not Synchronized_Present (N) then
11242 ("private extension of& must be explicitly synchronized",
11246 -- However, by 3.9.4(16/2), a full type that is a record extension
11247 -- is never allowed to derive from a synchronized interface (note
11248 -- that interfaces must be excluded from this check, because those
11249 -- are represented by derived type definitions in some cases).
11251 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11252 and then not Interface_Present (Type_Definition (N))
11254 Error_Msg_N ("record extension cannot derive from synchronized "
11255 & "interface", Error_Node);
11259 -- Check that the characteristics of the progenitor are compatible
11260 -- with the explicit qualifier in the declaration.
11261 -- The check only applies to qualifiers that come from source.
11262 -- Limited_Present also appears in the declaration of corresponding
11263 -- records, and the check does not apply to them.
11265 if Limited_Present (Type_Def)
11267 Is_Concurrent_Record_Type (Defining_Identifier (N))
11269 if Is_Limited_Interface (Parent_Type)
11270 and then not Is_Limited_Interface (Iface_Id)
11273 ("progenitor & must be limited interface",
11274 Error_Node, Iface_Id);
11277 (Task_Present (Iface_Def)
11278 or else Protected_Present (Iface_Def)
11279 or else Synchronized_Present (Iface_Def))
11280 and then Nkind (N) /= N_Private_Extension_Declaration
11281 and then not Error_Posted (N)
11284 ("progenitor & must be limited interface",
11285 Error_Node, Iface_Id);
11288 -- Protected interfaces can only inherit from limited, synchronized
11289 -- or protected interfaces.
11291 elsif Nkind (N) = N_Full_Type_Declaration
11292 and then Protected_Present (Type_Def)
11294 if Limited_Present (Iface_Def)
11295 or else Synchronized_Present (Iface_Def)
11296 or else Protected_Present (Iface_Def)
11300 elsif Task_Present (Iface_Def) then
11301 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11302 & "from task interface", Error_Node);
11305 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11306 & "from non-limited interface", Error_Node);
11309 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
11310 -- limited and synchronized.
11312 elsif Synchronized_Present (Type_Def) then
11313 if Limited_Present (Iface_Def)
11314 or else Synchronized_Present (Iface_Def)
11318 elsif Protected_Present (Iface_Def)
11319 and then Nkind (N) /= N_Private_Extension_Declaration
11321 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11322 & "from protected interface", Error_Node);
11324 elsif Task_Present (Iface_Def)
11325 and then Nkind (N) /= N_Private_Extension_Declaration
11327 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11328 & "from task interface", Error_Node);
11330 elsif not Is_Limited_Interface (Iface_Id) then
11331 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11332 & "from non-limited interface", Error_Node);
11335 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
11336 -- synchronized or task interfaces.
11338 elsif Nkind (N) = N_Full_Type_Declaration
11339 and then Task_Present (Type_Def)
11341 if Limited_Present (Iface_Def)
11342 or else Synchronized_Present (Iface_Def)
11343 or else Task_Present (Iface_Def)
11347 elsif Protected_Present (Iface_Def) then
11348 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11349 & "protected interface", Error_Node);
11352 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11353 & "non-limited interface", Error_Node);
11358 -- Start of processing for Check_Interfaces
11361 if Is_Interface (Parent_Type) then
11362 if Is_Task_Interface (Parent_Type) then
11365 elsif Is_Protected_Interface (Parent_Type) then
11366 Is_Protected := True;
11370 if Nkind (N) = N_Private_Extension_Declaration then
11372 -- Check that progenitors are compatible with declaration
11374 Iface := First (Interface_List (Def));
11375 while Present (Iface) loop
11376 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11378 Parent_Node := Parent (Base_Type (Iface_Typ));
11379 Iface_Def := Type_Definition (Parent_Node);
11381 if not Is_Interface (Iface_Typ) then
11382 Diagnose_Interface (Iface, Iface_Typ);
11384 Check_Ifaces (Iface_Def, Iface);
11390 if Is_Task and Is_Protected then
11392 ("type cannot derive from task and protected interface", N);
11398 -- Full type declaration of derived type.
11399 -- Check compatibility with parent if it is interface type
11401 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11402 and then Is_Interface (Parent_Type)
11404 Parent_Node := Parent (Parent_Type);
11406 -- More detailed checks for interface varieties
11409 (Iface_Def => Type_Definition (Parent_Node),
11410 Error_Node => Subtype_Indication (Type_Definition (N)));
11413 Iface := First (Interface_List (Def));
11414 while Present (Iface) loop
11415 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11417 Parent_Node := Parent (Base_Type (Iface_Typ));
11418 Iface_Def := Type_Definition (Parent_Node);
11420 if not Is_Interface (Iface_Typ) then
11421 Diagnose_Interface (Iface, Iface_Typ);
11424 -- "The declaration of a specific descendant of an interface
11425 -- type freezes the interface type" RM 13.14
11427 Freeze_Before (N, Iface_Typ);
11428 Check_Ifaces (Iface_Def, Error_Node => Iface);
11434 if Is_Task and Is_Protected then
11436 ("type cannot derive from task and protected interface", N);
11438 end Check_Interfaces;
11440 ------------------------------------
11441 -- Check_Or_Process_Discriminants --
11442 ------------------------------------
11444 -- If an incomplete or private type declaration was already given for the
11445 -- type, the discriminants may have already been processed if they were
11446 -- present on the incomplete declaration. In this case a full conformance
11447 -- check has been performed in Find_Type_Name, and we then recheck here
11448 -- some properties that can't be checked on the partial view alone.
11449 -- Otherwise we call Process_Discriminants.
11451 procedure Check_Or_Process_Discriminants
11454 Prev : Entity_Id := Empty)
11457 if Has_Discriminants (T) then
11459 -- Discriminants are already set on T if they were already present
11460 -- on the partial view. Make them visible to component declarations.
11464 -- Discriminant on T (full view) referencing expr on partial view
11466 Prev_D : Entity_Id;
11467 -- Entity of corresponding discriminant on partial view
11470 -- Discriminant specification for full view, expression is
11471 -- the syntactic copy on full view (which has been checked for
11472 -- conformance with partial view), only used here to post error
11476 D := First_Discriminant (T);
11477 New_D := First (Discriminant_Specifications (N));
11478 while Present (D) loop
11479 Prev_D := Current_Entity (D);
11480 Set_Current_Entity (D);
11481 Set_Is_Immediately_Visible (D);
11482 Set_Homonym (D, Prev_D);
11484 -- Handle the case where there is an untagged partial view and
11485 -- the full view is tagged: must disallow discriminants with
11486 -- defaults, unless compiling for Ada 2012, which allows a
11487 -- limited tagged type to have defaulted discriminants (see
11488 -- AI05-0214). However, suppress error here if it was already
11489 -- reported on the default expression of the partial view.
11491 if Is_Tagged_Type (T)
11492 and then Present (Expression (Parent (D)))
11493 and then (not Is_Limited_Type (Current_Scope)
11494 or else Ada_Version < Ada_2012)
11495 and then not Error_Posted (Expression (Parent (D)))
11497 if Ada_Version >= Ada_2012 then
11499 ("discriminants of nonlimited tagged type cannot have "
11501 Expression (New_D));
11504 ("discriminants of tagged type cannot have defaults",
11505 Expression (New_D));
11509 -- Ada 2005 (AI-230): Access discriminant allowed in
11510 -- non-limited record types.
11512 if Ada_Version < Ada_2005 then
11514 -- This restriction gets applied to the full type here. It
11515 -- has already been applied earlier to the partial view.
11517 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
11520 Next_Discriminant (D);
11525 elsif Present (Discriminant_Specifications (N)) then
11526 Process_Discriminants (N, Prev);
11528 end Check_Or_Process_Discriminants;
11530 ----------------------
11531 -- Check_Real_Bound --
11532 ----------------------
11534 procedure Check_Real_Bound (Bound : Node_Id) is
11536 if not Is_Real_Type (Etype (Bound)) then
11538 ("bound in real type definition must be of real type", Bound);
11540 elsif not Is_OK_Static_Expression (Bound) then
11541 Flag_Non_Static_Expr
11542 ("non-static expression used for real type bound!", Bound);
11549 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
11551 Resolve (Bound, Standard_Float);
11552 end Check_Real_Bound;
11554 ------------------------------
11555 -- Complete_Private_Subtype --
11556 ------------------------------
11558 procedure Complete_Private_Subtype
11561 Full_Base : Entity_Id;
11562 Related_Nod : Node_Id)
11564 Save_Next_Entity : Entity_Id;
11565 Save_Homonym : Entity_Id;
11568 -- Set semantic attributes for (implicit) private subtype completion.
11569 -- If the full type has no discriminants, then it is a copy of the
11570 -- full view of the base. Otherwise, it is a subtype of the base with
11571 -- a possible discriminant constraint. Save and restore the original
11572 -- Next_Entity field of full to ensure that the calls to Copy_Node do
11573 -- not corrupt the entity chain.
11575 -- Note that the type of the full view is the same entity as the type
11576 -- of the partial view. In this fashion, the subtype has access to the
11577 -- correct view of the parent.
11579 Save_Next_Entity := Next_Entity (Full);
11580 Save_Homonym := Homonym (Priv);
11582 case Ekind (Full_Base) is
11583 when E_Record_Type |
11589 Copy_Node (Priv, Full);
11591 Set_Has_Discriminants
11592 (Full, Has_Discriminants (Full_Base));
11593 Set_Has_Unknown_Discriminants
11594 (Full, Has_Unknown_Discriminants (Full_Base));
11595 Set_First_Entity (Full, First_Entity (Full_Base));
11596 Set_Last_Entity (Full, Last_Entity (Full_Base));
11598 -- If the underlying base type is constrained, we know that the
11599 -- full view of the subtype is constrained as well (the converse
11600 -- is not necessarily true).
11602 if Is_Constrained (Full_Base) then
11603 Set_Is_Constrained (Full);
11607 Copy_Node (Full_Base, Full);
11609 Set_Chars (Full, Chars (Priv));
11610 Conditional_Delay (Full, Priv);
11611 Set_Sloc (Full, Sloc (Priv));
11614 Set_Next_Entity (Full, Save_Next_Entity);
11615 Set_Homonym (Full, Save_Homonym);
11616 Set_Associated_Node_For_Itype (Full, Related_Nod);
11618 -- Set common attributes for all subtypes: kind, convention, etc.
11620 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
11621 Set_Convention (Full, Convention (Full_Base));
11623 -- The Etype of the full view is inconsistent. Gigi needs to see the
11624 -- structural full view, which is what the current scheme gives: the
11625 -- Etype of the full view is the etype of the full base. However, if the
11626 -- full base is a derived type, the full view then looks like a subtype
11627 -- of the parent, not a subtype of the full base. If instead we write:
11629 -- Set_Etype (Full, Full_Base);
11631 -- then we get inconsistencies in the front-end (confusion between
11632 -- views). Several outstanding bugs are related to this ???
11634 Set_Is_First_Subtype (Full, False);
11635 Set_Scope (Full, Scope (Priv));
11636 Set_Size_Info (Full, Full_Base);
11637 Set_RM_Size (Full, RM_Size (Full_Base));
11638 Set_Is_Itype (Full);
11640 -- A subtype of a private-type-without-discriminants, whose full-view
11641 -- has discriminants with default expressions, is not constrained.
11643 if not Has_Discriminants (Priv) then
11644 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
11646 if Has_Discriminants (Full_Base) then
11647 Set_Discriminant_Constraint
11648 (Full, Discriminant_Constraint (Full_Base));
11650 -- The partial view may have been indefinite, the full view
11653 Set_Has_Unknown_Discriminants
11654 (Full, Has_Unknown_Discriminants (Full_Base));
11658 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
11659 Set_Depends_On_Private (Full, Has_Private_Component (Full));
11661 -- Freeze the private subtype entity if its parent is delayed, and not
11662 -- already frozen. We skip this processing if the type is an anonymous
11663 -- subtype of a record component, or is the corresponding record of a
11664 -- protected type, since these are processed when the enclosing type
11667 if not Is_Type (Scope (Full)) then
11668 Set_Has_Delayed_Freeze (Full,
11669 Has_Delayed_Freeze (Full_Base)
11670 and then (not Is_Frozen (Full_Base)));
11673 Set_Freeze_Node (Full, Empty);
11674 Set_Is_Frozen (Full, False);
11675 Set_Full_View (Priv, Full);
11677 if Has_Discriminants (Full) then
11678 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
11679 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
11681 if Has_Unknown_Discriminants (Full) then
11682 Set_Discriminant_Constraint (Full, No_Elist);
11686 if Ekind (Full_Base) = E_Record_Type
11687 and then Has_Discriminants (Full_Base)
11688 and then Has_Discriminants (Priv) -- might not, if errors
11689 and then not Has_Unknown_Discriminants (Priv)
11690 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
11692 Create_Constrained_Components
11693 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
11695 -- If the full base is itself derived from private, build a congruent
11696 -- subtype of its underlying type, for use by the back end. For a
11697 -- constrained record component, the declaration cannot be placed on
11698 -- the component list, but it must nevertheless be built an analyzed, to
11699 -- supply enough information for Gigi to compute the size of component.
11701 elsif Ekind (Full_Base) in Private_Kind
11702 and then Is_Derived_Type (Full_Base)
11703 and then Has_Discriminants (Full_Base)
11704 and then (Ekind (Current_Scope) /= E_Record_Subtype)
11706 if not Is_Itype (Priv)
11708 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
11710 Build_Underlying_Full_View
11711 (Parent (Priv), Full, Etype (Full_Base));
11713 elsif Nkind (Related_Nod) = N_Component_Declaration then
11714 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
11717 elsif Is_Record_Type (Full_Base) then
11719 -- Show Full is simply a renaming of Full_Base
11721 Set_Cloned_Subtype (Full, Full_Base);
11724 -- It is unsafe to share the bounds of a scalar type, because the Itype
11725 -- is elaborated on demand, and if a bound is non-static then different
11726 -- orders of elaboration in different units will lead to different
11727 -- external symbols.
11729 if Is_Scalar_Type (Full_Base) then
11730 Set_Scalar_Range (Full,
11731 Make_Range (Sloc (Related_Nod),
11733 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
11735 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
11737 -- This completion inherits the bounds of the full parent, but if
11738 -- the parent is an unconstrained floating point type, so is the
11741 if Is_Floating_Point_Type (Full_Base) then
11742 Set_Includes_Infinities
11743 (Scalar_Range (Full), Has_Infinities (Full_Base));
11747 -- ??? It seems that a lot of fields are missing that should be copied
11748 -- from Full_Base to Full. Here are some that are introduced in a
11749 -- non-disruptive way but a cleanup is necessary.
11751 if Is_Tagged_Type (Full_Base) then
11752 Set_Is_Tagged_Type (Full);
11753 Set_Direct_Primitive_Operations
11754 (Full, Direct_Primitive_Operations (Full_Base));
11755 Set_No_Tagged_Streams_Pragma
11756 (Full, No_Tagged_Streams_Pragma (Full_Base));
11758 -- Inherit class_wide type of full_base in case the partial view was
11759 -- not tagged. Otherwise it has already been created when the private
11760 -- subtype was analyzed.
11762 if No (Class_Wide_Type (Full)) then
11763 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
11766 -- If this is a subtype of a protected or task type, constrain its
11767 -- corresponding record, unless this is a subtype without constraints,
11768 -- i.e. a simple renaming as with an actual subtype in an instance.
11770 elsif Is_Concurrent_Type (Full_Base) then
11771 if Has_Discriminants (Full)
11772 and then Present (Corresponding_Record_Type (Full_Base))
11774 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
11776 Set_Corresponding_Record_Type (Full,
11777 Constrain_Corresponding_Record
11778 (Full, Corresponding_Record_Type (Full_Base), Related_Nod));
11781 Set_Corresponding_Record_Type (Full,
11782 Corresponding_Record_Type (Full_Base));
11786 -- Link rep item chain, and also setting of Has_Predicates from private
11787 -- subtype to full subtype, since we will need these on the full subtype
11788 -- to create the predicate function. Note that the full subtype may
11789 -- already have rep items, inherited from the full view of the base
11790 -- type, so we must be sure not to overwrite these entries.
11795 Next_Item : Node_Id;
11798 Item := First_Rep_Item (Full);
11800 -- If no existing rep items on full type, we can just link directly
11801 -- to the list of items on the private type, if any exist.. Same if
11802 -- the rep items are only those inherited from the base
11805 or else Nkind (Item) /= N_Aspect_Specification
11806 or else Entity (Item) = Full_Base)
11807 and then Present (First_Rep_Item (Priv))
11809 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
11811 -- Otherwise, search to the end of items currently linked to the full
11812 -- subtype and append the private items to the end. However, if Priv
11813 -- and Full already have the same list of rep items, then the append
11814 -- is not done, as that would create a circularity.
11816 elsif Item /= First_Rep_Item (Priv) then
11819 Next_Item := Next_Rep_Item (Item);
11820 exit when No (Next_Item);
11823 -- If the private view has aspect specifications, the full view
11824 -- inherits them. Since these aspects may already have been
11825 -- attached to the full view during derivation, do not append
11826 -- them if already present.
11828 if Item = First_Rep_Item (Priv) then
11834 -- And link the private type items at the end of the chain
11837 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
11842 -- Make sure Has_Predicates is set on full type if it is set on the
11843 -- private type. Note that it may already be set on the full type and
11844 -- if so, we don't want to unset it. Similarly, propagate information
11845 -- about delayed aspects, because the corresponding pragmas must be
11846 -- analyzed when one of the views is frozen. This last step is needed
11847 -- in particular when the full type is a scalar type for which an
11848 -- anonymous base type is constructed.
11850 if Has_Predicates (Priv) then
11851 Set_Has_Predicates (Full);
11854 if Has_Delayed_Aspects (Priv) then
11855 Set_Has_Delayed_Aspects (Full);
11857 end Complete_Private_Subtype;
11859 ----------------------------
11860 -- Constant_Redeclaration --
11861 ----------------------------
11863 procedure Constant_Redeclaration
11868 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
11869 Obj_Def : constant Node_Id := Object_Definition (N);
11872 procedure Check_Possible_Deferred_Completion
11873 (Prev_Id : Entity_Id;
11874 Prev_Obj_Def : Node_Id;
11875 Curr_Obj_Def : Node_Id);
11876 -- Determine whether the two object definitions describe the partial
11877 -- and the full view of a constrained deferred constant. Generate
11878 -- a subtype for the full view and verify that it statically matches
11879 -- the subtype of the partial view.
11881 procedure Check_Recursive_Declaration (Typ : Entity_Id);
11882 -- If deferred constant is an access type initialized with an allocator,
11883 -- check whether there is an illegal recursion in the definition,
11884 -- through a default value of some record subcomponent. This is normally
11885 -- detected when generating init procs, but requires this additional
11886 -- mechanism when expansion is disabled.
11888 ----------------------------------------
11889 -- Check_Possible_Deferred_Completion --
11890 ----------------------------------------
11892 procedure Check_Possible_Deferred_Completion
11893 (Prev_Id : Entity_Id;
11894 Prev_Obj_Def : Node_Id;
11895 Curr_Obj_Def : Node_Id)
11898 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
11899 and then Present (Constraint (Prev_Obj_Def))
11900 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
11901 and then Present (Constraint (Curr_Obj_Def))
11904 Loc : constant Source_Ptr := Sloc (N);
11905 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
11906 Decl : constant Node_Id :=
11907 Make_Subtype_Declaration (Loc,
11908 Defining_Identifier => Def_Id,
11909 Subtype_Indication =>
11910 Relocate_Node (Curr_Obj_Def));
11913 Insert_Before_And_Analyze (N, Decl);
11914 Set_Etype (Id, Def_Id);
11916 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
11917 Error_Msg_Sloc := Sloc (Prev_Id);
11918 Error_Msg_N ("subtype does not statically match deferred "
11919 & "declaration #", N);
11923 end Check_Possible_Deferred_Completion;
11925 ---------------------------------
11926 -- Check_Recursive_Declaration --
11927 ---------------------------------
11929 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
11933 if Is_Record_Type (Typ) then
11934 Comp := First_Component (Typ);
11935 while Present (Comp) loop
11936 if Comes_From_Source (Comp) then
11937 if Present (Expression (Parent (Comp)))
11938 and then Is_Entity_Name (Expression (Parent (Comp)))
11939 and then Entity (Expression (Parent (Comp))) = Prev
11941 Error_Msg_Sloc := Sloc (Parent (Comp));
11943 ("illegal circularity with declaration for & #",
11947 elsif Is_Record_Type (Etype (Comp)) then
11948 Check_Recursive_Declaration (Etype (Comp));
11952 Next_Component (Comp);
11955 end Check_Recursive_Declaration;
11957 -- Start of processing for Constant_Redeclaration
11960 if Nkind (Parent (Prev)) = N_Object_Declaration then
11961 if Nkind (Object_Definition
11962 (Parent (Prev))) = N_Subtype_Indication
11964 -- Find type of new declaration. The constraints of the two
11965 -- views must match statically, but there is no point in
11966 -- creating an itype for the full view.
11968 if Nkind (Obj_Def) = N_Subtype_Indication then
11969 Find_Type (Subtype_Mark (Obj_Def));
11970 New_T := Entity (Subtype_Mark (Obj_Def));
11973 Find_Type (Obj_Def);
11974 New_T := Entity (Obj_Def);
11980 -- The full view may impose a constraint, even if the partial
11981 -- view does not, so construct the subtype.
11983 New_T := Find_Type_Of_Object (Obj_Def, N);
11988 -- Current declaration is illegal, diagnosed below in Enter_Name
11994 -- If previous full declaration or a renaming declaration exists, or if
11995 -- a homograph is present, let Enter_Name handle it, either with an
11996 -- error or with the removal of an overridden implicit subprogram.
11997 -- The previous one is a full declaration if it has an expression
11998 -- (which in the case of an aggregate is indicated by the Init flag).
12000 if Ekind (Prev) /= E_Constant
12001 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
12002 or else Present (Expression (Parent (Prev)))
12003 or else Has_Init_Expression (Parent (Prev))
12004 or else Present (Full_View (Prev))
12008 -- Verify that types of both declarations match, or else that both types
12009 -- are anonymous access types whose designated subtypes statically match
12010 -- (as allowed in Ada 2005 by AI-385).
12012 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
12014 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
12015 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
12016 or else Is_Access_Constant (Etype (New_T)) /=
12017 Is_Access_Constant (Etype (Prev))
12018 or else Can_Never_Be_Null (Etype (New_T)) /=
12019 Can_Never_Be_Null (Etype (Prev))
12020 or else Null_Exclusion_Present (Parent (Prev)) /=
12021 Null_Exclusion_Present (Parent (Id))
12022 or else not Subtypes_Statically_Match
12023 (Designated_Type (Etype (Prev)),
12024 Designated_Type (Etype (New_T))))
12026 Error_Msg_Sloc := Sloc (Prev);
12027 Error_Msg_N ("type does not match declaration#", N);
12028 Set_Full_View (Prev, Id);
12029 Set_Etype (Id, Any_Type);
12031 -- A deferred constant whose type is an anonymous array is always
12032 -- illegal (unless imported). A detailed error message might be
12033 -- helpful for Ada beginners.
12035 if Nkind (Object_Definition (Parent (Prev)))
12036 = N_Constrained_Array_Definition
12037 and then Nkind (Object_Definition (N))
12038 = N_Constrained_Array_Definition
12040 Error_Msg_N ("\each anonymous array is a distinct type", N);
12041 Error_Msg_N ("a deferred constant must have a named type",
12042 Object_Definition (Parent (Prev)));
12046 Null_Exclusion_Present (Parent (Prev))
12047 and then not Null_Exclusion_Present (N)
12049 Error_Msg_Sloc := Sloc (Prev);
12050 Error_Msg_N ("null-exclusion does not match declaration#", N);
12051 Set_Full_View (Prev, Id);
12052 Set_Etype (Id, Any_Type);
12054 -- If so, process the full constant declaration
12057 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
12058 -- the deferred declaration is constrained, then the subtype defined
12059 -- by the subtype_indication in the full declaration shall match it
12062 Check_Possible_Deferred_Completion
12064 Prev_Obj_Def => Object_Definition (Parent (Prev)),
12065 Curr_Obj_Def => Obj_Def);
12067 Set_Full_View (Prev, Id);
12068 Set_Is_Public (Id, Is_Public (Prev));
12069 Set_Is_Internal (Id);
12070 Append_Entity (Id, Current_Scope);
12072 -- Check ALIASED present if present before (RM 7.4(7))
12074 if Is_Aliased (Prev)
12075 and then not Aliased_Present (N)
12077 Error_Msg_Sloc := Sloc (Prev);
12078 Error_Msg_N ("ALIASED required (see declaration #)", N);
12081 -- Check that placement is in private part and that the incomplete
12082 -- declaration appeared in the visible part.
12084 if Ekind (Current_Scope) = E_Package
12085 and then not In_Private_Part (Current_Scope)
12087 Error_Msg_Sloc := Sloc (Prev);
12089 ("full constant for declaration # must be in private part", N);
12091 elsif Ekind (Current_Scope) = E_Package
12093 List_Containing (Parent (Prev)) /=
12094 Visible_Declarations (Package_Specification (Current_Scope))
12097 ("deferred constant must be declared in visible part",
12101 if Is_Access_Type (T)
12102 and then Nkind (Expression (N)) = N_Allocator
12104 Check_Recursive_Declaration (Designated_Type (T));
12107 -- A deferred constant is a visible entity. If type has invariants,
12108 -- verify that the initial value satisfies them.
12110 if Has_Invariants (T) and then Present (Invariant_Procedure (T)) then
12112 Make_Invariant_Call (New_Occurrence_Of (Prev, Sloc (N))));
12115 end Constant_Redeclaration;
12117 ----------------------
12118 -- Constrain_Access --
12119 ----------------------
12121 procedure Constrain_Access
12122 (Def_Id : in out Entity_Id;
12124 Related_Nod : Node_Id)
12126 T : constant Entity_Id := Entity (Subtype_Mark (S));
12127 Desig_Type : constant Entity_Id := Designated_Type (T);
12128 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
12129 Constraint_OK : Boolean := True;
12132 if Is_Array_Type (Desig_Type) then
12133 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
12135 elsif (Is_Record_Type (Desig_Type)
12136 or else Is_Incomplete_Or_Private_Type (Desig_Type))
12137 and then not Is_Constrained (Desig_Type)
12139 -- ??? The following code is a temporary bypass to ignore a
12140 -- discriminant constraint on access type if it is constraining
12141 -- the current record. Avoid creating the implicit subtype of the
12142 -- record we are currently compiling since right now, we cannot
12143 -- handle these. For now, just return the access type itself.
12145 if Desig_Type = Current_Scope
12146 and then No (Def_Id)
12148 Set_Ekind (Desig_Subtype, E_Record_Subtype);
12149 Def_Id := Entity (Subtype_Mark (S));
12151 -- This call added to ensure that the constraint is analyzed
12152 -- (needed for a B test). Note that we still return early from
12153 -- this procedure to avoid recursive processing. ???
12155 Constrain_Discriminated_Type
12156 (Desig_Subtype, S, Related_Nod, For_Access => True);
12160 -- Enforce rule that the constraint is illegal if there is an
12161 -- unconstrained view of the designated type. This means that the
12162 -- partial view (either a private type declaration or a derivation
12163 -- from a private type) has no discriminants. (Defect Report
12164 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
12166 -- Rule updated for Ada 2005: The private type is said to have
12167 -- a constrained partial view, given that objects of the type
12168 -- can be declared. Furthermore, the rule applies to all access
12169 -- types, unlike the rule concerning default discriminants (see
12172 if (Ekind (T) = E_General_Access_Type or else Ada_Version >= Ada_2005)
12173 and then Has_Private_Declaration (Desig_Type)
12174 and then In_Open_Scopes (Scope (Desig_Type))
12175 and then Has_Discriminants (Desig_Type)
12178 Pack : constant Node_Id :=
12179 Unit_Declaration_Node (Scope (Desig_Type));
12184 if Nkind (Pack) = N_Package_Declaration then
12185 Decls := Visible_Declarations (Specification (Pack));
12186 Decl := First (Decls);
12187 while Present (Decl) loop
12188 if (Nkind (Decl) = N_Private_Type_Declaration
12189 and then Chars (Defining_Identifier (Decl)) =
12190 Chars (Desig_Type))
12193 (Nkind (Decl) = N_Full_Type_Declaration
12195 Chars (Defining_Identifier (Decl)) =
12197 and then Is_Derived_Type (Desig_Type)
12199 Has_Private_Declaration (Etype (Desig_Type)))
12201 if No (Discriminant_Specifications (Decl)) then
12203 ("cannot constrain access type if designated "
12204 & "type has constrained partial view", S);
12216 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
12217 For_Access => True);
12219 elsif Is_Concurrent_Type (Desig_Type)
12220 and then not Is_Constrained (Desig_Type)
12222 Constrain_Concurrent (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
12225 Error_Msg_N ("invalid constraint on access type", S);
12227 -- We simply ignore an invalid constraint
12229 Desig_Subtype := Desig_Type;
12230 Constraint_OK := False;
12233 if No (Def_Id) then
12234 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
12236 Set_Ekind (Def_Id, E_Access_Subtype);
12239 if Constraint_OK then
12240 Set_Etype (Def_Id, Base_Type (T));
12242 if Is_Private_Type (Desig_Type) then
12243 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
12246 Set_Etype (Def_Id, Any_Type);
12249 Set_Size_Info (Def_Id, T);
12250 Set_Is_Constrained (Def_Id, Constraint_OK);
12251 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
12252 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12253 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
12255 Conditional_Delay (Def_Id, T);
12257 -- AI-363 : Subtypes of general access types whose designated types have
12258 -- default discriminants are disallowed. In instances, the rule has to
12259 -- be checked against the actual, of which T is the subtype. In a
12260 -- generic body, the rule is checked assuming that the actual type has
12261 -- defaulted discriminants.
12263 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
12264 if Ekind (Base_Type (T)) = E_General_Access_Type
12265 and then Has_Defaulted_Discriminants (Desig_Type)
12267 if Ada_Version < Ada_2005 then
12269 ("access subtype of general access type would not " &
12270 "be allowed in Ada 2005?y?", S);
12273 ("access subtype of general access type not allowed", S);
12276 Error_Msg_N ("\discriminants have defaults", S);
12278 elsif Is_Access_Type (T)
12279 and then Is_Generic_Type (Desig_Type)
12280 and then Has_Discriminants (Desig_Type)
12281 and then In_Package_Body (Current_Scope)
12283 if Ada_Version < Ada_2005 then
12285 ("access subtype would not be allowed in generic body "
12286 & "in Ada 2005?y?", S);
12289 ("access subtype not allowed in generic body", S);
12293 ("\designated type is a discriminated formal", S);
12296 end Constrain_Access;
12298 ---------------------
12299 -- Constrain_Array --
12300 ---------------------
12302 procedure Constrain_Array
12303 (Def_Id : in out Entity_Id;
12305 Related_Nod : Node_Id;
12306 Related_Id : Entity_Id;
12307 Suffix : Character)
12309 C : constant Node_Id := Constraint (SI);
12310 Number_Of_Constraints : Nat := 0;
12313 Constraint_OK : Boolean := True;
12316 T := Entity (Subtype_Mark (SI));
12318 if Is_Access_Type (T) then
12319 T := Designated_Type (T);
12322 -- If an index constraint follows a subtype mark in a subtype indication
12323 -- then the type or subtype denoted by the subtype mark must not already
12324 -- impose an index constraint. The subtype mark must denote either an
12325 -- unconstrained array type or an access type whose designated type
12326 -- is such an array type... (RM 3.6.1)
12328 if Is_Constrained (T) then
12329 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
12330 Constraint_OK := False;
12333 S := First (Constraints (C));
12334 while Present (S) loop
12335 Number_Of_Constraints := Number_Of_Constraints + 1;
12339 -- In either case, the index constraint must provide a discrete
12340 -- range for each index of the array type and the type of each
12341 -- discrete range must be the same as that of the corresponding
12342 -- index. (RM 3.6.1)
12344 if Number_Of_Constraints /= Number_Dimensions (T) then
12345 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
12346 Constraint_OK := False;
12349 S := First (Constraints (C));
12350 Index := First_Index (T);
12353 -- Apply constraints to each index type
12355 for J in 1 .. Number_Of_Constraints loop
12356 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
12364 if No (Def_Id) then
12366 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
12367 Set_Parent (Def_Id, Related_Nod);
12370 Set_Ekind (Def_Id, E_Array_Subtype);
12373 Set_Size_Info (Def_Id, (T));
12374 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12375 Set_Etype (Def_Id, Base_Type (T));
12377 if Constraint_OK then
12378 Set_First_Index (Def_Id, First (Constraints (C)));
12380 Set_First_Index (Def_Id, First_Index (T));
12383 Set_Is_Constrained (Def_Id, True);
12384 Set_Is_Aliased (Def_Id, Is_Aliased (T));
12385 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12387 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
12388 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
12390 -- A subtype does not inherit the Packed_Array_Impl_Type of is parent.
12391 -- We need to initialize the attribute because if Def_Id is previously
12392 -- analyzed through a limited_with clause, it will have the attributes
12393 -- of an incomplete type, one of which is an Elist that overlaps the
12394 -- Packed_Array_Impl_Type field.
12396 Set_Packed_Array_Impl_Type (Def_Id, Empty);
12398 -- Build a freeze node if parent still needs one. Also make sure that
12399 -- the Depends_On_Private status is set because the subtype will need
12400 -- reprocessing at the time the base type does, and also we must set a
12401 -- conditional delay.
12403 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
12404 Conditional_Delay (Def_Id, T);
12405 end Constrain_Array;
12407 ------------------------------
12408 -- Constrain_Component_Type --
12409 ------------------------------
12411 function Constrain_Component_Type
12413 Constrained_Typ : Entity_Id;
12414 Related_Node : Node_Id;
12416 Constraints : Elist_Id) return Entity_Id
12418 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
12419 Compon_Type : constant Entity_Id := Etype (Comp);
12421 function Build_Constrained_Array_Type
12422 (Old_Type : Entity_Id) return Entity_Id;
12423 -- If Old_Type is an array type, one of whose indexes is constrained
12424 -- by a discriminant, build an Itype whose constraint replaces the
12425 -- discriminant with its value in the constraint.
12427 function Build_Constrained_Discriminated_Type
12428 (Old_Type : Entity_Id) return Entity_Id;
12429 -- Ditto for record components
12431 function Build_Constrained_Access_Type
12432 (Old_Type : Entity_Id) return Entity_Id;
12433 -- Ditto for access types. Makes use of previous two functions, to
12434 -- constrain designated type.
12436 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
12437 -- T is an array or discriminated type, C is a list of constraints
12438 -- that apply to T. This routine builds the constrained subtype.
12440 function Is_Discriminant (Expr : Node_Id) return Boolean;
12441 -- Returns True if Expr is a discriminant
12443 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
12444 -- Find the value of discriminant Discrim in Constraint
12446 -----------------------------------
12447 -- Build_Constrained_Access_Type --
12448 -----------------------------------
12450 function Build_Constrained_Access_Type
12451 (Old_Type : Entity_Id) return Entity_Id
12453 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
12455 Desig_Subtype : Entity_Id;
12459 -- if the original access type was not embedded in the enclosing
12460 -- type definition, there is no need to produce a new access
12461 -- subtype. In fact every access type with an explicit constraint
12462 -- generates an itype whose scope is the enclosing record.
12464 if not Is_Type (Scope (Old_Type)) then
12467 elsif Is_Array_Type (Desig_Type) then
12468 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
12470 elsif Has_Discriminants (Desig_Type) then
12472 -- This may be an access type to an enclosing record type for
12473 -- which we are constructing the constrained components. Return
12474 -- the enclosing record subtype. This is not always correct,
12475 -- but avoids infinite recursion. ???
12477 Desig_Subtype := Any_Type;
12479 for J in reverse 0 .. Scope_Stack.Last loop
12480 Scop := Scope_Stack.Table (J).Entity;
12483 and then Base_Type (Scop) = Base_Type (Desig_Type)
12485 Desig_Subtype := Scop;
12488 exit when not Is_Type (Scop);
12491 if Desig_Subtype = Any_Type then
12493 Build_Constrained_Discriminated_Type (Desig_Type);
12500 if Desig_Subtype /= Desig_Type then
12502 -- The Related_Node better be here or else we won't be able
12503 -- to attach new itypes to a node in the tree.
12505 pragma Assert (Present (Related_Node));
12507 Itype := Create_Itype (E_Access_Subtype, Related_Node);
12509 Set_Etype (Itype, Base_Type (Old_Type));
12510 Set_Size_Info (Itype, (Old_Type));
12511 Set_Directly_Designated_Type (Itype, Desig_Subtype);
12512 Set_Depends_On_Private (Itype, Has_Private_Component
12514 Set_Is_Access_Constant (Itype, Is_Access_Constant
12517 -- The new itype needs freezing when it depends on a not frozen
12518 -- type and the enclosing subtype needs freezing.
12520 if Has_Delayed_Freeze (Constrained_Typ)
12521 and then not Is_Frozen (Constrained_Typ)
12523 Conditional_Delay (Itype, Base_Type (Old_Type));
12531 end Build_Constrained_Access_Type;
12533 ----------------------------------
12534 -- Build_Constrained_Array_Type --
12535 ----------------------------------
12537 function Build_Constrained_Array_Type
12538 (Old_Type : Entity_Id) return Entity_Id
12542 Old_Index : Node_Id;
12543 Range_Node : Node_Id;
12544 Constr_List : List_Id;
12546 Need_To_Create_Itype : Boolean := False;
12549 Old_Index := First_Index (Old_Type);
12550 while Present (Old_Index) loop
12551 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12553 if Is_Discriminant (Lo_Expr)
12555 Is_Discriminant (Hi_Expr)
12557 Need_To_Create_Itype := True;
12560 Next_Index (Old_Index);
12563 if Need_To_Create_Itype then
12564 Constr_List := New_List;
12566 Old_Index := First_Index (Old_Type);
12567 while Present (Old_Index) loop
12568 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12570 if Is_Discriminant (Lo_Expr) then
12571 Lo_Expr := Get_Discr_Value (Lo_Expr);
12574 if Is_Discriminant (Hi_Expr) then
12575 Hi_Expr := Get_Discr_Value (Hi_Expr);
12580 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
12582 Append (Range_Node, To => Constr_List);
12584 Next_Index (Old_Index);
12587 return Build_Subtype (Old_Type, Constr_List);
12592 end Build_Constrained_Array_Type;
12594 ------------------------------------------
12595 -- Build_Constrained_Discriminated_Type --
12596 ------------------------------------------
12598 function Build_Constrained_Discriminated_Type
12599 (Old_Type : Entity_Id) return Entity_Id
12602 Constr_List : List_Id;
12603 Old_Constraint : Elmt_Id;
12605 Need_To_Create_Itype : Boolean := False;
12608 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12609 while Present (Old_Constraint) loop
12610 Expr := Node (Old_Constraint);
12612 if Is_Discriminant (Expr) then
12613 Need_To_Create_Itype := True;
12616 Next_Elmt (Old_Constraint);
12619 if Need_To_Create_Itype then
12620 Constr_List := New_List;
12622 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12623 while Present (Old_Constraint) loop
12624 Expr := Node (Old_Constraint);
12626 if Is_Discriminant (Expr) then
12627 Expr := Get_Discr_Value (Expr);
12630 Append (New_Copy_Tree (Expr), To => Constr_List);
12632 Next_Elmt (Old_Constraint);
12635 return Build_Subtype (Old_Type, Constr_List);
12640 end Build_Constrained_Discriminated_Type;
12642 -------------------
12643 -- Build_Subtype --
12644 -------------------
12646 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
12648 Subtyp_Decl : Node_Id;
12649 Def_Id : Entity_Id;
12650 Btyp : Entity_Id := Base_Type (T);
12653 -- The Related_Node better be here or else we won't be able to
12654 -- attach new itypes to a node in the tree.
12656 pragma Assert (Present (Related_Node));
12658 -- If the view of the component's type is incomplete or private
12659 -- with unknown discriminants, then the constraint must be applied
12660 -- to the full type.
12662 if Has_Unknown_Discriminants (Btyp)
12663 and then Present (Underlying_Type (Btyp))
12665 Btyp := Underlying_Type (Btyp);
12669 Make_Subtype_Indication (Loc,
12670 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
12671 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
12673 Def_Id := Create_Itype (Ekind (T), Related_Node);
12676 Make_Subtype_Declaration (Loc,
12677 Defining_Identifier => Def_Id,
12678 Subtype_Indication => Indic);
12680 Set_Parent (Subtyp_Decl, Parent (Related_Node));
12682 -- Itypes must be analyzed with checks off (see package Itypes)
12684 Analyze (Subtyp_Decl, Suppress => All_Checks);
12689 ---------------------
12690 -- Get_Discr_Value --
12691 ---------------------
12693 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
12698 -- The discriminant may be declared for the type, in which case we
12699 -- find it by iterating over the list of discriminants. If the
12700 -- discriminant is inherited from a parent type, it appears as the
12701 -- corresponding discriminant of the current type. This will be the
12702 -- case when constraining an inherited component whose constraint is
12703 -- given by a discriminant of the parent.
12705 D := First_Discriminant (Typ);
12706 E := First_Elmt (Constraints);
12708 while Present (D) loop
12709 if D = Entity (Discrim)
12710 or else D = CR_Discriminant (Entity (Discrim))
12711 or else Corresponding_Discriminant (D) = Entity (Discrim)
12716 Next_Discriminant (D);
12720 -- The Corresponding_Discriminant mechanism is incomplete, because
12721 -- the correspondence between new and old discriminants is not one
12722 -- to one: one new discriminant can constrain several old ones. In
12723 -- that case, scan sequentially the stored_constraint, the list of
12724 -- discriminants of the parents, and the constraints.
12726 -- Previous code checked for the present of the Stored_Constraint
12727 -- list for the derived type, but did not use it at all. Should it
12728 -- be present when the component is a discriminated task type?
12730 if Is_Derived_Type (Typ)
12731 and then Scope (Entity (Discrim)) = Etype (Typ)
12733 D := First_Discriminant (Etype (Typ));
12734 E := First_Elmt (Constraints);
12735 while Present (D) loop
12736 if D = Entity (Discrim) then
12740 Next_Discriminant (D);
12745 -- Something is wrong if we did not find the value
12747 raise Program_Error;
12748 end Get_Discr_Value;
12750 ---------------------
12751 -- Is_Discriminant --
12752 ---------------------
12754 function Is_Discriminant (Expr : Node_Id) return Boolean is
12755 Discrim_Scope : Entity_Id;
12758 if Denotes_Discriminant (Expr) then
12759 Discrim_Scope := Scope (Entity (Expr));
12761 -- Either we have a reference to one of Typ's discriminants,
12763 pragma Assert (Discrim_Scope = Typ
12765 -- or to the discriminants of the parent type, in the case
12766 -- of a derivation of a tagged type with variants.
12768 or else Discrim_Scope = Etype (Typ)
12769 or else Full_View (Discrim_Scope) = Etype (Typ)
12771 -- or same as above for the case where the discriminants
12772 -- were declared in Typ's private view.
12774 or else (Is_Private_Type (Discrim_Scope)
12775 and then Chars (Discrim_Scope) = Chars (Typ))
12777 -- or else we are deriving from the full view and the
12778 -- discriminant is declared in the private entity.
12780 or else (Is_Private_Type (Typ)
12781 and then Chars (Discrim_Scope) = Chars (Typ))
12783 -- Or we are constrained the corresponding record of a
12784 -- synchronized type that completes a private declaration.
12786 or else (Is_Concurrent_Record_Type (Typ)
12788 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
12790 -- or we have a class-wide type, in which case make sure the
12791 -- discriminant found belongs to the root type.
12793 or else (Is_Class_Wide_Type (Typ)
12794 and then Etype (Typ) = Discrim_Scope));
12799 -- In all other cases we have something wrong
12802 end Is_Discriminant;
12804 -- Start of processing for Constrain_Component_Type
12807 if Nkind (Parent (Comp)) = N_Component_Declaration
12808 and then Comes_From_Source (Parent (Comp))
12809 and then Comes_From_Source
12810 (Subtype_Indication (Component_Definition (Parent (Comp))))
12813 (Subtype_Indication (Component_Definition (Parent (Comp))))
12815 return Compon_Type;
12817 elsif Is_Array_Type (Compon_Type) then
12818 return Build_Constrained_Array_Type (Compon_Type);
12820 elsif Has_Discriminants (Compon_Type) then
12821 return Build_Constrained_Discriminated_Type (Compon_Type);
12823 elsif Is_Access_Type (Compon_Type) then
12824 return Build_Constrained_Access_Type (Compon_Type);
12827 return Compon_Type;
12829 end Constrain_Component_Type;
12831 --------------------------
12832 -- Constrain_Concurrent --
12833 --------------------------
12835 -- For concurrent types, the associated record value type carries the same
12836 -- discriminants, so when we constrain a concurrent type, we must constrain
12837 -- the corresponding record type as well.
12839 procedure Constrain_Concurrent
12840 (Def_Id : in out Entity_Id;
12842 Related_Nod : Node_Id;
12843 Related_Id : Entity_Id;
12844 Suffix : Character)
12846 -- Retrieve Base_Type to ensure getting to the concurrent type in the
12847 -- case of a private subtype (needed when only doing semantic analysis).
12849 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
12853 if Is_Access_Type (T_Ent) then
12854 T_Ent := Designated_Type (T_Ent);
12857 T_Val := Corresponding_Record_Type (T_Ent);
12859 if Present (T_Val) then
12861 if No (Def_Id) then
12862 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12865 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12867 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12868 Set_Corresponding_Record_Type (Def_Id,
12869 Constrain_Corresponding_Record (Def_Id, T_Val, Related_Nod));
12872 -- If there is no associated record, expansion is disabled and this
12873 -- is a generic context. Create a subtype in any case, so that
12874 -- semantic analysis can proceed.
12876 if No (Def_Id) then
12877 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12880 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12882 end Constrain_Concurrent;
12884 ------------------------------------
12885 -- Constrain_Corresponding_Record --
12886 ------------------------------------
12888 function Constrain_Corresponding_Record
12889 (Prot_Subt : Entity_Id;
12890 Corr_Rec : Entity_Id;
12891 Related_Nod : Node_Id) return Entity_Id
12893 T_Sub : constant Entity_Id :=
12894 Create_Itype (E_Record_Subtype, Related_Nod, Corr_Rec, 'C');
12897 Set_Etype (T_Sub, Corr_Rec);
12898 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
12899 Set_Is_Constrained (T_Sub, True);
12900 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
12901 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
12903 if Has_Discriminants (Prot_Subt) then -- False only if errors.
12904 Set_Discriminant_Constraint
12905 (T_Sub, Discriminant_Constraint (Prot_Subt));
12906 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
12907 Create_Constrained_Components
12908 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
12911 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
12913 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
12914 Conditional_Delay (T_Sub, Corr_Rec);
12917 -- This is a component subtype: it will be frozen in the context of
12918 -- the enclosing record's init_proc, so that discriminant references
12919 -- are resolved to discriminals. (Note: we used to skip freezing
12920 -- altogether in that case, which caused errors downstream for
12921 -- components of a bit packed array type).
12923 Set_Has_Delayed_Freeze (T_Sub);
12927 end Constrain_Corresponding_Record;
12929 -----------------------
12930 -- Constrain_Decimal --
12931 -----------------------
12933 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
12934 T : constant Entity_Id := Entity (Subtype_Mark (S));
12935 C : constant Node_Id := Constraint (S);
12936 Loc : constant Source_Ptr := Sloc (C);
12937 Range_Expr : Node_Id;
12938 Digits_Expr : Node_Id;
12943 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
12945 if Nkind (C) = N_Range_Constraint then
12946 Range_Expr := Range_Expression (C);
12947 Digits_Val := Digits_Value (T);
12950 pragma Assert (Nkind (C) = N_Digits_Constraint);
12952 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
12954 Digits_Expr := Digits_Expression (C);
12955 Analyze_And_Resolve (Digits_Expr, Any_Integer);
12957 Check_Digits_Expression (Digits_Expr);
12958 Digits_Val := Expr_Value (Digits_Expr);
12960 if Digits_Val > Digits_Value (T) then
12962 ("digits expression is incompatible with subtype", C);
12963 Digits_Val := Digits_Value (T);
12966 if Present (Range_Constraint (C)) then
12967 Range_Expr := Range_Expression (Range_Constraint (C));
12969 Range_Expr := Empty;
12973 Set_Etype (Def_Id, Base_Type (T));
12974 Set_Size_Info (Def_Id, (T));
12975 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12976 Set_Delta_Value (Def_Id, Delta_Value (T));
12977 Set_Scale_Value (Def_Id, Scale_Value (T));
12978 Set_Small_Value (Def_Id, Small_Value (T));
12979 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
12980 Set_Digits_Value (Def_Id, Digits_Val);
12982 -- Manufacture range from given digits value if no range present
12984 if No (Range_Expr) then
12985 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
12989 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
12991 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
12994 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
12995 Set_Discrete_RM_Size (Def_Id);
12997 -- Unconditionally delay the freeze, since we cannot set size
12998 -- information in all cases correctly until the freeze point.
13000 Set_Has_Delayed_Freeze (Def_Id);
13001 end Constrain_Decimal;
13003 ----------------------------------
13004 -- Constrain_Discriminated_Type --
13005 ----------------------------------
13007 procedure Constrain_Discriminated_Type
13008 (Def_Id : Entity_Id;
13010 Related_Nod : Node_Id;
13011 For_Access : Boolean := False)
13013 E : constant Entity_Id := Entity (Subtype_Mark (S));
13016 Elist : Elist_Id := New_Elmt_List;
13018 procedure Fixup_Bad_Constraint;
13019 -- This is called after finding a bad constraint, and after having
13020 -- posted an appropriate error message. The mission is to leave the
13021 -- entity T in as reasonable state as possible.
13023 --------------------------
13024 -- Fixup_Bad_Constraint --
13025 --------------------------
13027 procedure Fixup_Bad_Constraint is
13029 -- Set a reasonable Ekind for the entity. For an incomplete type,
13030 -- we can't do much, but for other types, we can set the proper
13031 -- corresponding subtype kind.
13033 if Ekind (T) = E_Incomplete_Type then
13034 Set_Ekind (Def_Id, Ekind (T));
13036 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
13039 -- Set Etype to the known type, to reduce chances of cascaded errors
13041 Set_Etype (Def_Id, E);
13042 Set_Error_Posted (Def_Id);
13043 end Fixup_Bad_Constraint;
13045 -- Start of processing for Constrain_Discriminated_Type
13048 C := Constraint (S);
13050 -- A discriminant constraint is only allowed in a subtype indication,
13051 -- after a subtype mark. This subtype mark must denote either a type
13052 -- with discriminants, or an access type whose designated type is a
13053 -- type with discriminants. A discriminant constraint specifies the
13054 -- values of these discriminants (RM 3.7.2(5)).
13056 T := Base_Type (Entity (Subtype_Mark (S)));
13058 if Is_Access_Type (T) then
13059 T := Designated_Type (T);
13062 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
13063 -- Avoid generating an error for access-to-incomplete subtypes.
13065 if Ada_Version >= Ada_2005
13066 and then Ekind (T) = E_Incomplete_Type
13067 and then Nkind (Parent (S)) = N_Subtype_Declaration
13068 and then not Is_Itype (Def_Id)
13070 -- A little sanity check, emit an error message if the type
13071 -- has discriminants to begin with. Type T may be a regular
13072 -- incomplete type or imported via a limited with clause.
13074 if Has_Discriminants (T)
13075 or else (From_Limited_With (T)
13076 and then Present (Non_Limited_View (T))
13077 and then Nkind (Parent (Non_Limited_View (T))) =
13078 N_Full_Type_Declaration
13079 and then Present (Discriminant_Specifications
13080 (Parent (Non_Limited_View (T)))))
13083 ("(Ada 2005) incomplete subtype may not be constrained", C);
13085 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13088 Fixup_Bad_Constraint;
13091 -- Check that the type has visible discriminants. The type may be
13092 -- a private type with unknown discriminants whose full view has
13093 -- discriminants which are invisible.
13095 elsif not Has_Discriminants (T)
13097 (Has_Unknown_Discriminants (T)
13098 and then Is_Private_Type (T))
13100 Error_Msg_N ("invalid constraint: type has no discriminant", C);
13101 Fixup_Bad_Constraint;
13104 elsif Is_Constrained (E)
13105 or else (Ekind (E) = E_Class_Wide_Subtype
13106 and then Present (Discriminant_Constraint (E)))
13108 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
13109 Fixup_Bad_Constraint;
13113 -- T may be an unconstrained subtype (e.g. a generic actual).
13114 -- Constraint applies to the base type.
13116 T := Base_Type (T);
13118 Elist := Build_Discriminant_Constraints (T, S);
13120 -- If the list returned was empty we had an error in building the
13121 -- discriminant constraint. We have also already signalled an error
13122 -- in the incomplete type case
13124 if Is_Empty_Elmt_List (Elist) then
13125 Fixup_Bad_Constraint;
13129 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
13130 end Constrain_Discriminated_Type;
13132 ---------------------------
13133 -- Constrain_Enumeration --
13134 ---------------------------
13136 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
13137 T : constant Entity_Id := Entity (Subtype_Mark (S));
13138 C : constant Node_Id := Constraint (S);
13141 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13143 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
13145 Set_Etype (Def_Id, Base_Type (T));
13146 Set_Size_Info (Def_Id, (T));
13147 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13148 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13150 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13152 Set_Discrete_RM_Size (Def_Id);
13153 end Constrain_Enumeration;
13155 ----------------------
13156 -- Constrain_Float --
13157 ----------------------
13159 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
13160 T : constant Entity_Id := Entity (Subtype_Mark (S));
13166 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
13168 Set_Etype (Def_Id, Base_Type (T));
13169 Set_Size_Info (Def_Id, (T));
13170 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13172 -- Process the constraint
13174 C := Constraint (S);
13176 -- Digits constraint present
13178 if Nkind (C) = N_Digits_Constraint then
13180 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13181 Check_Restriction (No_Obsolescent_Features, C);
13183 if Warn_On_Obsolescent_Feature then
13185 ("subtype digits constraint is an " &
13186 "obsolescent feature (RM J.3(8))?j?", C);
13189 D := Digits_Expression (C);
13190 Analyze_And_Resolve (D, Any_Integer);
13191 Check_Digits_Expression (D);
13192 Set_Digits_Value (Def_Id, Expr_Value (D));
13194 -- Check that digits value is in range. Obviously we can do this
13195 -- at compile time, but it is strictly a runtime check, and of
13196 -- course there is an ACVC test that checks this.
13198 if Digits_Value (Def_Id) > Digits_Value (T) then
13199 Error_Msg_Uint_1 := Digits_Value (T);
13200 Error_Msg_N ("??digits value is too large, maximum is ^", D);
13202 Make_Raise_Constraint_Error (Sloc (D),
13203 Reason => CE_Range_Check_Failed);
13204 Insert_Action (Declaration_Node (Def_Id), Rais);
13207 C := Range_Constraint (C);
13209 -- No digits constraint present
13212 Set_Digits_Value (Def_Id, Digits_Value (T));
13215 -- Range constraint present
13217 if Nkind (C) = N_Range_Constraint then
13218 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13220 -- No range constraint present
13223 pragma Assert (No (C));
13224 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13227 Set_Is_Constrained (Def_Id);
13228 end Constrain_Float;
13230 ---------------------
13231 -- Constrain_Index --
13232 ---------------------
13234 procedure Constrain_Index
13237 Related_Nod : Node_Id;
13238 Related_Id : Entity_Id;
13239 Suffix : Character;
13240 Suffix_Index : Nat)
13242 Def_Id : Entity_Id;
13243 R : Node_Id := Empty;
13244 T : constant Entity_Id := Etype (Index);
13248 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
13249 Set_Etype (Def_Id, Base_Type (T));
13251 if Nkind (S) = N_Range
13253 (Nkind (S) = N_Attribute_Reference
13254 and then Attribute_Name (S) = Name_Range)
13256 -- A Range attribute will be transformed into N_Range by Resolve
13262 Process_Range_Expr_In_Decl (R, T);
13264 if not Error_Posted (S)
13266 (Nkind (S) /= N_Range
13267 or else not Covers (T, (Etype (Low_Bound (S))))
13268 or else not Covers (T, (Etype (High_Bound (S)))))
13270 if Base_Type (T) /= Any_Type
13271 and then Etype (Low_Bound (S)) /= Any_Type
13272 and then Etype (High_Bound (S)) /= Any_Type
13274 Error_Msg_N ("range expected", S);
13278 elsif Nkind (S) = N_Subtype_Indication then
13280 -- The parser has verified that this is a discrete indication
13282 Resolve_Discrete_Subtype_Indication (S, T);
13283 Bad_Predicated_Subtype_Use
13284 ("subtype& has predicate, not allowed in index constraint",
13285 S, Entity (Subtype_Mark (S)));
13287 R := Range_Expression (Constraint (S));
13289 -- Capture values of bounds and generate temporaries for them if
13290 -- needed, since checks may cause duplication of the expressions
13291 -- which must not be reevaluated.
13293 -- The forced evaluation removes side effects from expressions, which
13294 -- should occur also in GNATprove mode. Otherwise, we end up with
13295 -- unexpected insertions of actions at places where this is not
13296 -- supposed to occur, e.g. on default parameters of a call.
13298 if Expander_Active or GNATprove_Mode then
13300 (Low_Bound (R), Related_Id => Def_Id, Is_Low_Bound => True);
13302 (High_Bound (R), Related_Id => Def_Id, Is_High_Bound => True);
13305 elsif Nkind (S) = N_Discriminant_Association then
13307 -- Syntactically valid in subtype indication
13309 Error_Msg_N ("invalid index constraint", S);
13310 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13313 -- Subtype_Mark case, no anonymous subtypes to construct
13318 if Is_Entity_Name (S) then
13319 if not Is_Type (Entity (S)) then
13320 Error_Msg_N ("expect subtype mark for index constraint", S);
13322 elsif Base_Type (Entity (S)) /= Base_Type (T) then
13323 Wrong_Type (S, Base_Type (T));
13325 -- Check error of subtype with predicate in index constraint
13328 Bad_Predicated_Subtype_Use
13329 ("subtype& has predicate, not allowed in index constraint",
13336 Error_Msg_N ("invalid index constraint", S);
13337 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13342 -- Complete construction of the Itype
13344 if Is_Modular_Integer_Type (T) then
13345 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13347 elsif Is_Integer_Type (T) then
13348 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13351 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13352 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13353 Set_First_Literal (Def_Id, First_Literal (T));
13356 Set_Size_Info (Def_Id, (T));
13357 Set_RM_Size (Def_Id, RM_Size (T));
13358 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13360 Set_Scalar_Range (Def_Id, R);
13362 Set_Etype (S, Def_Id);
13363 Set_Discrete_RM_Size (Def_Id);
13364 end Constrain_Index;
13366 -----------------------
13367 -- Constrain_Integer --
13368 -----------------------
13370 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
13371 T : constant Entity_Id := Entity (Subtype_Mark (S));
13372 C : constant Node_Id := Constraint (S);
13375 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13377 if Is_Modular_Integer_Type (T) then
13378 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13380 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13383 Set_Etype (Def_Id, Base_Type (T));
13384 Set_Size_Info (Def_Id, (T));
13385 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13386 Set_Discrete_RM_Size (Def_Id);
13387 end Constrain_Integer;
13389 ------------------------------
13390 -- Constrain_Ordinary_Fixed --
13391 ------------------------------
13393 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
13394 T : constant Entity_Id := Entity (Subtype_Mark (S));
13400 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
13401 Set_Etype (Def_Id, Base_Type (T));
13402 Set_Size_Info (Def_Id, (T));
13403 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13404 Set_Small_Value (Def_Id, Small_Value (T));
13406 -- Process the constraint
13408 C := Constraint (S);
13410 -- Delta constraint present
13412 if Nkind (C) = N_Delta_Constraint then
13414 Check_SPARK_05_Restriction ("delta constraint is not allowed", S);
13415 Check_Restriction (No_Obsolescent_Features, C);
13417 if Warn_On_Obsolescent_Feature then
13419 ("subtype delta constraint is an " &
13420 "obsolescent feature (RM J.3(7))?j?");
13423 D := Delta_Expression (C);
13424 Analyze_And_Resolve (D, Any_Real);
13425 Check_Delta_Expression (D);
13426 Set_Delta_Value (Def_Id, Expr_Value_R (D));
13428 -- Check that delta value is in range. Obviously we can do this
13429 -- at compile time, but it is strictly a runtime check, and of
13430 -- course there is an ACVC test that checks this.
13432 if Delta_Value (Def_Id) < Delta_Value (T) then
13433 Error_Msg_N ("??delta value is too small", D);
13435 Make_Raise_Constraint_Error (Sloc (D),
13436 Reason => CE_Range_Check_Failed);
13437 Insert_Action (Declaration_Node (Def_Id), Rais);
13440 C := Range_Constraint (C);
13442 -- No delta constraint present
13445 Set_Delta_Value (Def_Id, Delta_Value (T));
13448 -- Range constraint present
13450 if Nkind (C) = N_Range_Constraint then
13451 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13453 -- No range constraint present
13456 pragma Assert (No (C));
13457 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13460 Set_Discrete_RM_Size (Def_Id);
13462 -- Unconditionally delay the freeze, since we cannot set size
13463 -- information in all cases correctly until the freeze point.
13465 Set_Has_Delayed_Freeze (Def_Id);
13466 end Constrain_Ordinary_Fixed;
13468 -----------------------
13469 -- Contain_Interface --
13470 -----------------------
13472 function Contain_Interface
13473 (Iface : Entity_Id;
13474 Ifaces : Elist_Id) return Boolean
13476 Iface_Elmt : Elmt_Id;
13479 if Present (Ifaces) then
13480 Iface_Elmt := First_Elmt (Ifaces);
13481 while Present (Iface_Elmt) loop
13482 if Node (Iface_Elmt) = Iface then
13486 Next_Elmt (Iface_Elmt);
13491 end Contain_Interface;
13493 ---------------------------
13494 -- Convert_Scalar_Bounds --
13495 ---------------------------
13497 procedure Convert_Scalar_Bounds
13499 Parent_Type : Entity_Id;
13500 Derived_Type : Entity_Id;
13503 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
13510 -- Defend against previous errors
13512 if No (Scalar_Range (Derived_Type)) then
13513 Check_Error_Detected;
13517 Lo := Build_Scalar_Bound
13518 (Type_Low_Bound (Derived_Type),
13519 Parent_Type, Implicit_Base);
13521 Hi := Build_Scalar_Bound
13522 (Type_High_Bound (Derived_Type),
13523 Parent_Type, Implicit_Base);
13530 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
13532 Set_Parent (Rng, N);
13533 Set_Scalar_Range (Derived_Type, Rng);
13535 -- Analyze the bounds
13537 Analyze_And_Resolve (Lo, Implicit_Base);
13538 Analyze_And_Resolve (Hi, Implicit_Base);
13540 -- Analyze the range itself, except that we do not analyze it if
13541 -- the bounds are real literals, and we have a fixed-point type.
13542 -- The reason for this is that we delay setting the bounds in this
13543 -- case till we know the final Small and Size values (see circuit
13544 -- in Freeze.Freeze_Fixed_Point_Type for further details).
13546 if Is_Fixed_Point_Type (Parent_Type)
13547 and then Nkind (Lo) = N_Real_Literal
13548 and then Nkind (Hi) = N_Real_Literal
13552 -- Here we do the analysis of the range
13554 -- Note: we do this manually, since if we do a normal Analyze and
13555 -- Resolve call, there are problems with the conversions used for
13556 -- the derived type range.
13559 Set_Etype (Rng, Implicit_Base);
13560 Set_Analyzed (Rng, True);
13562 end Convert_Scalar_Bounds;
13564 -------------------
13565 -- Copy_And_Swap --
13566 -------------------
13568 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
13570 -- Initialize new full declaration entity by copying the pertinent
13571 -- fields of the corresponding private declaration entity.
13573 -- We temporarily set Ekind to a value appropriate for a type to
13574 -- avoid assert failures in Einfo from checking for setting type
13575 -- attributes on something that is not a type. Ekind (Priv) is an
13576 -- appropriate choice, since it allowed the attributes to be set
13577 -- in the first place. This Ekind value will be modified later.
13579 Set_Ekind (Full, Ekind (Priv));
13581 -- Also set Etype temporarily to Any_Type, again, in the absence
13582 -- of errors, it will be properly reset, and if there are errors,
13583 -- then we want a value of Any_Type to remain.
13585 Set_Etype (Full, Any_Type);
13587 -- Now start copying attributes
13589 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
13591 if Has_Discriminants (Full) then
13592 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
13593 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
13596 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
13597 Set_Homonym (Full, Homonym (Priv));
13598 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
13599 Set_Is_Public (Full, Is_Public (Priv));
13600 Set_Is_Pure (Full, Is_Pure (Priv));
13601 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
13602 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
13603 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
13604 Set_Has_Pragma_Unreferenced_Objects
13605 (Full, Has_Pragma_Unreferenced_Objects
13608 Conditional_Delay (Full, Priv);
13610 if Is_Tagged_Type (Full) then
13611 Set_Direct_Primitive_Operations
13612 (Full, Direct_Primitive_Operations (Priv));
13613 Set_No_Tagged_Streams_Pragma
13614 (Full, No_Tagged_Streams_Pragma (Priv));
13616 if Is_Base_Type (Priv) then
13617 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
13621 Set_Is_Volatile (Full, Is_Volatile (Priv));
13622 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
13623 Set_Scope (Full, Scope (Priv));
13624 Set_Next_Entity (Full, Next_Entity (Priv));
13625 Set_First_Entity (Full, First_Entity (Priv));
13626 Set_Last_Entity (Full, Last_Entity (Priv));
13628 -- If access types have been recorded for later handling, keep them in
13629 -- the full view so that they get handled when the full view freeze
13630 -- node is expanded.
13632 if Present (Freeze_Node (Priv))
13633 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
13635 Ensure_Freeze_Node (Full);
13636 Set_Access_Types_To_Process
13637 (Freeze_Node (Full),
13638 Access_Types_To_Process (Freeze_Node (Priv)));
13641 -- Swap the two entities. Now Private is the full type entity and Full
13642 -- is the private one. They will be swapped back at the end of the
13643 -- private part. This swapping ensures that the entity that is visible
13644 -- in the private part is the full declaration.
13646 Exchange_Entities (Priv, Full);
13647 Append_Entity (Full, Scope (Full));
13650 -------------------------------------
13651 -- Copy_Array_Base_Type_Attributes --
13652 -------------------------------------
13654 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
13656 Set_Component_Alignment (T1, Component_Alignment (T2));
13657 Set_Component_Type (T1, Component_Type (T2));
13658 Set_Component_Size (T1, Component_Size (T2));
13659 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
13660 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
13661 Set_Has_Protected (T1, Has_Protected (T2));
13662 Set_Has_Task (T1, Has_Task (T2));
13663 Set_Is_Packed (T1, Is_Packed (T2));
13664 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
13665 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
13666 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
13667 end Copy_Array_Base_Type_Attributes;
13669 -----------------------------------
13670 -- Copy_Array_Subtype_Attributes --
13671 -----------------------------------
13673 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
13675 Set_Size_Info (T1, T2);
13677 Set_First_Index (T1, First_Index (T2));
13678 Set_Is_Aliased (T1, Is_Aliased (T2));
13679 Set_Is_Volatile (T1, Is_Volatile (T2));
13680 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
13681 Set_Is_Constrained (T1, Is_Constrained (T2));
13682 Set_Depends_On_Private (T1, Has_Private_Component (T2));
13683 Inherit_Rep_Item_Chain (T1, T2);
13684 Set_Convention (T1, Convention (T2));
13685 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
13686 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
13687 Set_Packed_Array_Impl_Type (T1, Packed_Array_Impl_Type (T2));
13688 end Copy_Array_Subtype_Attributes;
13690 -----------------------------------
13691 -- Create_Constrained_Components --
13692 -----------------------------------
13694 procedure Create_Constrained_Components
13696 Decl_Node : Node_Id;
13698 Constraints : Elist_Id)
13700 Loc : constant Source_Ptr := Sloc (Subt);
13701 Comp_List : constant Elist_Id := New_Elmt_List;
13702 Parent_Type : constant Entity_Id := Etype (Typ);
13703 Assoc_List : constant List_Id := New_List;
13704 Discr_Val : Elmt_Id;
13708 Is_Static : Boolean := True;
13710 procedure Collect_Fixed_Components (Typ : Entity_Id);
13711 -- Collect parent type components that do not appear in a variant part
13713 procedure Create_All_Components;
13714 -- Iterate over Comp_List to create the components of the subtype
13716 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
13717 -- Creates a new component from Old_Compon, copying all the fields from
13718 -- it, including its Etype, inserts the new component in the Subt entity
13719 -- chain and returns the new component.
13721 function Is_Variant_Record (T : Entity_Id) return Boolean;
13722 -- If true, and discriminants are static, collect only components from
13723 -- variants selected by discriminant values.
13725 ------------------------------
13726 -- Collect_Fixed_Components --
13727 ------------------------------
13729 procedure Collect_Fixed_Components (Typ : Entity_Id) is
13731 -- Build association list for discriminants, and find components of the
13732 -- variant part selected by the values of the discriminants.
13734 Old_C := First_Discriminant (Typ);
13735 Discr_Val := First_Elmt (Constraints);
13736 while Present (Old_C) loop
13737 Append_To (Assoc_List,
13738 Make_Component_Association (Loc,
13739 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
13740 Expression => New_Copy (Node (Discr_Val))));
13742 Next_Elmt (Discr_Val);
13743 Next_Discriminant (Old_C);
13746 -- The tag and the possible parent component are unconditionally in
13749 if Is_Tagged_Type (Typ) or else Has_Controlled_Component (Typ) then
13750 Old_C := First_Component (Typ);
13751 while Present (Old_C) loop
13752 if Nam_In (Chars (Old_C), Name_uTag, Name_uParent) then
13753 Append_Elmt (Old_C, Comp_List);
13756 Next_Component (Old_C);
13759 end Collect_Fixed_Components;
13761 ---------------------------
13762 -- Create_All_Components --
13763 ---------------------------
13765 procedure Create_All_Components is
13769 Comp := First_Elmt (Comp_List);
13770 while Present (Comp) loop
13771 Old_C := Node (Comp);
13772 New_C := Create_Component (Old_C);
13776 Constrain_Component_Type
13777 (Old_C, Subt, Decl_Node, Typ, Constraints));
13778 Set_Is_Public (New_C, Is_Public (Subt));
13782 end Create_All_Components;
13784 ----------------------
13785 -- Create_Component --
13786 ----------------------
13788 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
13789 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
13792 if Ekind (Old_Compon) = E_Discriminant
13793 and then Is_Completely_Hidden (Old_Compon)
13795 -- This is a shadow discriminant created for a discriminant of
13796 -- the parent type, which needs to be present in the subtype.
13797 -- Give the shadow discriminant an internal name that cannot
13798 -- conflict with that of visible components.
13800 Set_Chars (New_Compon, New_Internal_Name ('C'));
13803 -- Set the parent so we have a proper link for freezing etc. This is
13804 -- not a real parent pointer, since of course our parent does not own
13805 -- up to us and reference us, we are an illegitimate child of the
13806 -- original parent.
13808 Set_Parent (New_Compon, Parent (Old_Compon));
13810 -- If the old component's Esize was already determined and is a
13811 -- static value, then the new component simply inherits it. Otherwise
13812 -- the old component's size may require run-time determination, but
13813 -- the new component's size still might be statically determinable
13814 -- (if, for example it has a static constraint). In that case we want
13815 -- Layout_Type to recompute the component's size, so we reset its
13816 -- size and positional fields.
13818 if Frontend_Layout_On_Target
13819 and then not Known_Static_Esize (Old_Compon)
13821 Set_Esize (New_Compon, Uint_0);
13822 Init_Normalized_First_Bit (New_Compon);
13823 Init_Normalized_Position (New_Compon);
13824 Init_Normalized_Position_Max (New_Compon);
13827 -- We do not want this node marked as Comes_From_Source, since
13828 -- otherwise it would get first class status and a separate cross-
13829 -- reference line would be generated. Illegitimate children do not
13830 -- rate such recognition.
13832 Set_Comes_From_Source (New_Compon, False);
13834 -- But it is a real entity, and a birth certificate must be properly
13835 -- registered by entering it into the entity list.
13837 Enter_Name (New_Compon);
13840 end Create_Component;
13842 -----------------------
13843 -- Is_Variant_Record --
13844 -----------------------
13846 function Is_Variant_Record (T : Entity_Id) return Boolean is
13848 return Nkind (Parent (T)) = N_Full_Type_Declaration
13849 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
13850 and then Present (Component_List (Type_Definition (Parent (T))))
13853 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
13854 end Is_Variant_Record;
13856 -- Start of processing for Create_Constrained_Components
13859 pragma Assert (Subt /= Base_Type (Subt));
13860 pragma Assert (Typ = Base_Type (Typ));
13862 Set_First_Entity (Subt, Empty);
13863 Set_Last_Entity (Subt, Empty);
13865 -- Check whether constraint is fully static, in which case we can
13866 -- optimize the list of components.
13868 Discr_Val := First_Elmt (Constraints);
13869 while Present (Discr_Val) loop
13870 if not Is_OK_Static_Expression (Node (Discr_Val)) then
13871 Is_Static := False;
13875 Next_Elmt (Discr_Val);
13878 Set_Has_Static_Discriminants (Subt, Is_Static);
13882 -- Inherit the discriminants of the parent type
13884 Add_Discriminants : declare
13890 Old_C := First_Discriminant (Typ);
13892 while Present (Old_C) loop
13893 Num_Disc := Num_Disc + 1;
13894 New_C := Create_Component (Old_C);
13895 Set_Is_Public (New_C, Is_Public (Subt));
13896 Next_Discriminant (Old_C);
13899 -- For an untagged derived subtype, the number of discriminants may
13900 -- be smaller than the number of inherited discriminants, because
13901 -- several of them may be renamed by a single new discriminant or
13902 -- constrained. In this case, add the hidden discriminants back into
13903 -- the subtype, because they need to be present if the optimizer of
13904 -- the GCC 4.x back-end decides to break apart assignments between
13905 -- objects using the parent view into member-wise assignments.
13909 if Is_Derived_Type (Typ)
13910 and then not Is_Tagged_Type (Typ)
13912 Old_C := First_Stored_Discriminant (Typ);
13914 while Present (Old_C) loop
13915 Num_Gird := Num_Gird + 1;
13916 Next_Stored_Discriminant (Old_C);
13920 if Num_Gird > Num_Disc then
13922 -- Find out multiple uses of new discriminants, and add hidden
13923 -- components for the extra renamed discriminants. We recognize
13924 -- multiple uses through the Corresponding_Discriminant of a
13925 -- new discriminant: if it constrains several old discriminants,
13926 -- this field points to the last one in the parent type. The
13927 -- stored discriminants of the derived type have the same name
13928 -- as those of the parent.
13932 New_Discr : Entity_Id;
13933 Old_Discr : Entity_Id;
13936 Constr := First_Elmt (Stored_Constraint (Typ));
13937 Old_Discr := First_Stored_Discriminant (Typ);
13938 while Present (Constr) loop
13939 if Is_Entity_Name (Node (Constr))
13940 and then Ekind (Entity (Node (Constr))) = E_Discriminant
13942 New_Discr := Entity (Node (Constr));
13944 if Chars (Corresponding_Discriminant (New_Discr)) /=
13947 -- The new discriminant has been used to rename a
13948 -- subsequent old discriminant. Introduce a shadow
13949 -- component for the current old discriminant.
13951 New_C := Create_Component (Old_Discr);
13952 Set_Original_Record_Component (New_C, Old_Discr);
13956 -- The constraint has eliminated the old discriminant.
13957 -- Introduce a shadow component.
13959 New_C := Create_Component (Old_Discr);
13960 Set_Original_Record_Component (New_C, Old_Discr);
13963 Next_Elmt (Constr);
13964 Next_Stored_Discriminant (Old_Discr);
13968 end Add_Discriminants;
13971 and then Is_Variant_Record (Typ)
13973 Collect_Fixed_Components (Typ);
13975 Gather_Components (
13977 Component_List (Type_Definition (Parent (Typ))),
13978 Governed_By => Assoc_List,
13980 Report_Errors => Errors);
13981 pragma Assert (not Errors);
13983 Create_All_Components;
13985 -- If the subtype declaration is created for a tagged type derivation
13986 -- with constraints, we retrieve the record definition of the parent
13987 -- type to select the components of the proper variant.
13990 and then Is_Tagged_Type (Typ)
13991 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
13993 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
13994 and then Is_Variant_Record (Parent_Type)
13996 Collect_Fixed_Components (Typ);
14000 Component_List (Type_Definition (Parent (Parent_Type))),
14001 Governed_By => Assoc_List,
14003 Report_Errors => Errors);
14005 -- Note: previously there was a check at this point that no errors
14006 -- were detected. As a consequence of AI05-220 there may be an error
14007 -- if an inherited discriminant that controls a variant has a non-
14008 -- static constraint.
14010 -- If the tagged derivation has a type extension, collect all the
14011 -- new components therein.
14013 if Present (Record_Extension_Part (Type_Definition (Parent (Typ))))
14015 Old_C := First_Component (Typ);
14016 while Present (Old_C) loop
14017 if Original_Record_Component (Old_C) = Old_C
14018 and then Chars (Old_C) /= Name_uTag
14019 and then Chars (Old_C) /= Name_uParent
14021 Append_Elmt (Old_C, Comp_List);
14024 Next_Component (Old_C);
14028 Create_All_Components;
14031 -- If discriminants are not static, or if this is a multi-level type
14032 -- extension, we have to include all components of the parent type.
14034 Old_C := First_Component (Typ);
14035 while Present (Old_C) loop
14036 New_C := Create_Component (Old_C);
14040 Constrain_Component_Type
14041 (Old_C, Subt, Decl_Node, Typ, Constraints));
14042 Set_Is_Public (New_C, Is_Public (Subt));
14044 Next_Component (Old_C);
14049 end Create_Constrained_Components;
14051 ------------------------------------------
14052 -- Decimal_Fixed_Point_Type_Declaration --
14053 ------------------------------------------
14055 procedure Decimal_Fixed_Point_Type_Declaration
14059 Loc : constant Source_Ptr := Sloc (Def);
14060 Digs_Expr : constant Node_Id := Digits_Expression (Def);
14061 Delta_Expr : constant Node_Id := Delta_Expression (Def);
14062 Implicit_Base : Entity_Id;
14069 Check_SPARK_05_Restriction
14070 ("decimal fixed point type is not allowed", Def);
14071 Check_Restriction (No_Fixed_Point, Def);
14073 -- Create implicit base type
14076 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
14077 Set_Etype (Implicit_Base, Implicit_Base);
14079 -- Analyze and process delta expression
14081 Analyze_And_Resolve (Delta_Expr, Universal_Real);
14083 Check_Delta_Expression (Delta_Expr);
14084 Delta_Val := Expr_Value_R (Delta_Expr);
14086 -- Check delta is power of 10, and determine scale value from it
14092 Scale_Val := Uint_0;
14095 if Val < Ureal_1 then
14096 while Val < Ureal_1 loop
14097 Val := Val * Ureal_10;
14098 Scale_Val := Scale_Val + 1;
14101 if Scale_Val > 18 then
14102 Error_Msg_N ("scale exceeds maximum value of 18", Def);
14103 Scale_Val := UI_From_Int (+18);
14107 while Val > Ureal_1 loop
14108 Val := Val / Ureal_10;
14109 Scale_Val := Scale_Val - 1;
14112 if Scale_Val < -18 then
14113 Error_Msg_N ("scale is less than minimum value of -18", Def);
14114 Scale_Val := UI_From_Int (-18);
14118 if Val /= Ureal_1 then
14119 Error_Msg_N ("delta expression must be a power of 10", Def);
14120 Delta_Val := Ureal_10 ** (-Scale_Val);
14124 -- Set delta, scale and small (small = delta for decimal type)
14126 Set_Delta_Value (Implicit_Base, Delta_Val);
14127 Set_Scale_Value (Implicit_Base, Scale_Val);
14128 Set_Small_Value (Implicit_Base, Delta_Val);
14130 -- Analyze and process digits expression
14132 Analyze_And_Resolve (Digs_Expr, Any_Integer);
14133 Check_Digits_Expression (Digs_Expr);
14134 Digs_Val := Expr_Value (Digs_Expr);
14136 if Digs_Val > 18 then
14137 Digs_Val := UI_From_Int (+18);
14138 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
14141 Set_Digits_Value (Implicit_Base, Digs_Val);
14142 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
14144 -- Set range of base type from digits value for now. This will be
14145 -- expanded to represent the true underlying base range by Freeze.
14147 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
14149 -- Note: We leave size as zero for now, size will be set at freeze
14150 -- time. We have to do this for ordinary fixed-point, because the size
14151 -- depends on the specified small, and we might as well do the same for
14152 -- decimal fixed-point.
14154 pragma Assert (Esize (Implicit_Base) = Uint_0);
14156 -- If there are bounds given in the declaration use them as the
14157 -- bounds of the first named subtype.
14159 if Present (Real_Range_Specification (Def)) then
14161 RRS : constant Node_Id := Real_Range_Specification (Def);
14162 Low : constant Node_Id := Low_Bound (RRS);
14163 High : constant Node_Id := High_Bound (RRS);
14168 Analyze_And_Resolve (Low, Any_Real);
14169 Analyze_And_Resolve (High, Any_Real);
14170 Check_Real_Bound (Low);
14171 Check_Real_Bound (High);
14172 Low_Val := Expr_Value_R (Low);
14173 High_Val := Expr_Value_R (High);
14175 if Low_Val < (-Bound_Val) then
14177 ("range low bound too small for digits value", Low);
14178 Low_Val := -Bound_Val;
14181 if High_Val > Bound_Val then
14183 ("range high bound too large for digits value", High);
14184 High_Val := Bound_Val;
14187 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
14190 -- If no explicit range, use range that corresponds to given
14191 -- digits value. This will end up as the final range for the
14195 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
14198 -- Complete entity for first subtype. The inheritance of the rep item
14199 -- chain ensures that SPARK-related pragmas are not clobbered when the
14200 -- decimal fixed point type acts as a full view of a private type.
14202 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
14203 Set_Etype (T, Implicit_Base);
14204 Set_Size_Info (T, Implicit_Base);
14205 Inherit_Rep_Item_Chain (T, Implicit_Base);
14206 Set_Digits_Value (T, Digs_Val);
14207 Set_Delta_Value (T, Delta_Val);
14208 Set_Small_Value (T, Delta_Val);
14209 Set_Scale_Value (T, Scale_Val);
14210 Set_Is_Constrained (T);
14211 end Decimal_Fixed_Point_Type_Declaration;
14213 -----------------------------------
14214 -- Derive_Progenitor_Subprograms --
14215 -----------------------------------
14217 procedure Derive_Progenitor_Subprograms
14218 (Parent_Type : Entity_Id;
14219 Tagged_Type : Entity_Id)
14224 Iface_Elmt : Elmt_Id;
14225 Iface_Subp : Entity_Id;
14226 New_Subp : Entity_Id := Empty;
14227 Prim_Elmt : Elmt_Id;
14232 pragma Assert (Ada_Version >= Ada_2005
14233 and then Is_Record_Type (Tagged_Type)
14234 and then Is_Tagged_Type (Tagged_Type)
14235 and then Has_Interfaces (Tagged_Type));
14237 -- Step 1: Transfer to the full-view primitives associated with the
14238 -- partial-view that cover interface primitives. Conceptually this
14239 -- work should be done later by Process_Full_View; done here to
14240 -- simplify its implementation at later stages. It can be safely
14241 -- done here because interfaces must be visible in the partial and
14242 -- private view (RM 7.3(7.3/2)).
14244 -- Small optimization: This work is only required if the parent may
14245 -- have entities whose Alias attribute reference an interface primitive.
14246 -- Such a situation may occur if the parent is an abstract type and the
14247 -- primitive has not been yet overridden or if the parent is a generic
14248 -- formal type covering interfaces.
14250 -- If the tagged type is not abstract, it cannot have abstract
14251 -- primitives (the only entities in the list of primitives of
14252 -- non-abstract tagged types that can reference abstract primitives
14253 -- through its Alias attribute are the internal entities that have
14254 -- attribute Interface_Alias, and these entities are generated later
14255 -- by Add_Internal_Interface_Entities).
14257 if In_Private_Part (Current_Scope)
14258 and then (Is_Abstract_Type (Parent_Type)
14260 Is_Generic_Type (Parent_Type))
14262 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
14263 while Present (Elmt) loop
14264 Subp := Node (Elmt);
14266 -- At this stage it is not possible to have entities in the list
14267 -- of primitives that have attribute Interface_Alias.
14269 pragma Assert (No (Interface_Alias (Subp)));
14271 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
14273 if Is_Interface (Typ) then
14274 E := Find_Primitive_Covering_Interface
14275 (Tagged_Type => Tagged_Type,
14276 Iface_Prim => Subp);
14279 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
14281 Replace_Elmt (Elmt, E);
14282 Remove_Homonym (Subp);
14290 -- Step 2: Add primitives of progenitors that are not implemented by
14291 -- parents of Tagged_Type.
14293 if Present (Interfaces (Base_Type (Tagged_Type))) then
14294 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
14295 while Present (Iface_Elmt) loop
14296 Iface := Node (Iface_Elmt);
14298 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
14299 while Present (Prim_Elmt) loop
14300 Iface_Subp := Node (Prim_Elmt);
14302 -- Exclude derivation of predefined primitives except those
14303 -- that come from source, or are inherited from one that comes
14304 -- from source. Required to catch declarations of equality
14305 -- operators of interfaces. For example:
14307 -- type Iface is interface;
14308 -- function "=" (Left, Right : Iface) return Boolean;
14310 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
14311 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
14313 E := Find_Primitive_Covering_Interface
14314 (Tagged_Type => Tagged_Type,
14315 Iface_Prim => Iface_Subp);
14317 -- If not found we derive a new primitive leaving its alias
14318 -- attribute referencing the interface primitive.
14322 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14324 -- Ada 2012 (AI05-0197): If the covering primitive's name
14325 -- differs from the name of the interface primitive then it
14326 -- is a private primitive inherited from a parent type. In
14327 -- such case, given that Tagged_Type covers the interface,
14328 -- the inherited private primitive becomes visible. For such
14329 -- purpose we add a new entity that renames the inherited
14330 -- private primitive.
14332 elsif Chars (E) /= Chars (Iface_Subp) then
14333 pragma Assert (Has_Suffix (E, 'P'));
14335 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14336 Set_Alias (New_Subp, E);
14337 Set_Is_Abstract_Subprogram (New_Subp,
14338 Is_Abstract_Subprogram (E));
14340 -- Propagate to the full view interface entities associated
14341 -- with the partial view.
14343 elsif In_Private_Part (Current_Scope)
14344 and then Present (Alias (E))
14345 and then Alias (E) = Iface_Subp
14347 List_Containing (Parent (E)) /=
14348 Private_Declarations
14350 (Unit_Declaration_Node (Current_Scope)))
14352 Append_Elmt (E, Primitive_Operations (Tagged_Type));
14356 Next_Elmt (Prim_Elmt);
14359 Next_Elmt (Iface_Elmt);
14362 end Derive_Progenitor_Subprograms;
14364 -----------------------
14365 -- Derive_Subprogram --
14366 -----------------------
14368 procedure Derive_Subprogram
14369 (New_Subp : in out Entity_Id;
14370 Parent_Subp : Entity_Id;
14371 Derived_Type : Entity_Id;
14372 Parent_Type : Entity_Id;
14373 Actual_Subp : Entity_Id := Empty)
14375 Formal : Entity_Id;
14376 -- Formal parameter of parent primitive operation
14378 Formal_Of_Actual : Entity_Id;
14379 -- Formal parameter of actual operation, when the derivation is to
14380 -- create a renaming for a primitive operation of an actual in an
14383 New_Formal : Entity_Id;
14384 -- Formal of inherited operation
14386 Visible_Subp : Entity_Id := Parent_Subp;
14388 function Is_Private_Overriding return Boolean;
14389 -- If Subp is a private overriding of a visible operation, the inherited
14390 -- operation derives from the overridden op (even though its body is the
14391 -- overriding one) and the inherited operation is visible now. See
14392 -- sem_disp to see the full details of the handling of the overridden
14393 -- subprogram, which is removed from the list of primitive operations of
14394 -- the type. The overridden subprogram is saved locally in Visible_Subp,
14395 -- and used to diagnose abstract operations that need overriding in the
14398 procedure Replace_Type (Id, New_Id : Entity_Id);
14399 -- When the type is an anonymous access type, create a new access type
14400 -- designating the derived type.
14402 procedure Set_Derived_Name;
14403 -- This procedure sets the appropriate Chars name for New_Subp. This
14404 -- is normally just a copy of the parent name. An exception arises for
14405 -- type support subprograms, where the name is changed to reflect the
14406 -- name of the derived type, e.g. if type foo is derived from type bar,
14407 -- then a procedure barDA is derived with a name fooDA.
14409 ---------------------------
14410 -- Is_Private_Overriding --
14411 ---------------------------
14413 function Is_Private_Overriding return Boolean is
14417 -- If the parent is not a dispatching operation there is no
14418 -- need to investigate overridings
14420 if not Is_Dispatching_Operation (Parent_Subp) then
14424 -- The visible operation that is overridden is a homonym of the
14425 -- parent subprogram. We scan the homonym chain to find the one
14426 -- whose alias is the subprogram we are deriving.
14428 Prev := Current_Entity (Parent_Subp);
14429 while Present (Prev) loop
14430 if Ekind (Prev) = Ekind (Parent_Subp)
14431 and then Alias (Prev) = Parent_Subp
14432 and then Scope (Parent_Subp) = Scope (Prev)
14433 and then not Is_Hidden (Prev)
14435 Visible_Subp := Prev;
14439 Prev := Homonym (Prev);
14443 end Is_Private_Overriding;
14449 procedure Replace_Type (Id, New_Id : Entity_Id) is
14450 Id_Type : constant Entity_Id := Etype (Id);
14451 Acc_Type : Entity_Id;
14452 Par : constant Node_Id := Parent (Derived_Type);
14455 -- When the type is an anonymous access type, create a new access
14456 -- type designating the derived type. This itype must be elaborated
14457 -- at the point of the derivation, not on subsequent calls that may
14458 -- be out of the proper scope for Gigi, so we insert a reference to
14459 -- it after the derivation.
14461 if Ekind (Id_Type) = E_Anonymous_Access_Type then
14463 Desig_Typ : Entity_Id := Designated_Type (Id_Type);
14466 if Ekind (Desig_Typ) = E_Record_Type_With_Private
14467 and then Present (Full_View (Desig_Typ))
14468 and then not Is_Private_Type (Parent_Type)
14470 Desig_Typ := Full_View (Desig_Typ);
14473 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
14475 -- Ada 2005 (AI-251): Handle also derivations of abstract
14476 -- interface primitives.
14478 or else (Is_Interface (Desig_Typ)
14479 and then not Is_Class_Wide_Type (Desig_Typ))
14481 Acc_Type := New_Copy (Id_Type);
14482 Set_Etype (Acc_Type, Acc_Type);
14483 Set_Scope (Acc_Type, New_Subp);
14485 -- Set size of anonymous access type. If we have an access
14486 -- to an unconstrained array, this is a fat pointer, so it
14487 -- is sizes at twice addtress size.
14489 if Is_Array_Type (Desig_Typ)
14490 and then not Is_Constrained (Desig_Typ)
14492 Init_Size (Acc_Type, 2 * System_Address_Size);
14494 -- Other cases use a thin pointer
14497 Init_Size (Acc_Type, System_Address_Size);
14500 -- Set remaining characterstics of anonymous access type
14502 Init_Alignment (Acc_Type);
14503 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
14505 Set_Etype (New_Id, Acc_Type);
14506 Set_Scope (New_Id, New_Subp);
14508 -- Create a reference to it
14510 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
14513 Set_Etype (New_Id, Id_Type);
14517 -- In Ada2012, a formal may have an incomplete type but the type
14518 -- derivation that inherits the primitive follows the full view.
14520 elsif Base_Type (Id_Type) = Base_Type (Parent_Type)
14522 (Ekind (Id_Type) = E_Record_Type_With_Private
14523 and then Present (Full_View (Id_Type))
14525 Base_Type (Full_View (Id_Type)) = Base_Type (Parent_Type))
14527 (Ada_Version >= Ada_2012
14528 and then Ekind (Id_Type) = E_Incomplete_Type
14529 and then Full_View (Id_Type) = Parent_Type)
14531 -- Constraint checks on formals are generated during expansion,
14532 -- based on the signature of the original subprogram. The bounds
14533 -- of the derived type are not relevant, and thus we can use
14534 -- the base type for the formals. However, the return type may be
14535 -- used in a context that requires that the proper static bounds
14536 -- be used (a case statement, for example) and for those cases
14537 -- we must use the derived type (first subtype), not its base.
14539 -- If the derived_type_definition has no constraints, we know that
14540 -- the derived type has the same constraints as the first subtype
14541 -- of the parent, and we can also use it rather than its base,
14542 -- which can lead to more efficient code.
14544 if Etype (Id) = Parent_Type then
14545 if Is_Scalar_Type (Parent_Type)
14547 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
14549 Set_Etype (New_Id, Derived_Type);
14551 elsif Nkind (Par) = N_Full_Type_Declaration
14553 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
14556 (Subtype_Indication (Type_Definition (Par)))
14558 Set_Etype (New_Id, Derived_Type);
14561 Set_Etype (New_Id, Base_Type (Derived_Type));
14565 Set_Etype (New_Id, Base_Type (Derived_Type));
14569 Set_Etype (New_Id, Etype (Id));
14573 ----------------------
14574 -- Set_Derived_Name --
14575 ----------------------
14577 procedure Set_Derived_Name is
14578 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
14580 if Nm = TSS_Null then
14581 Set_Chars (New_Subp, Chars (Parent_Subp));
14583 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
14585 end Set_Derived_Name;
14587 -- Start of processing for Derive_Subprogram
14590 New_Subp := New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
14591 Set_Ekind (New_Subp, Ekind (Parent_Subp));
14593 -- Check whether the inherited subprogram is a private operation that
14594 -- should be inherited but not yet made visible. Such subprograms can
14595 -- become visible at a later point (e.g., the private part of a public
14596 -- child unit) via Declare_Inherited_Private_Subprograms. If the
14597 -- following predicate is true, then this is not such a private
14598 -- operation and the subprogram simply inherits the name of the parent
14599 -- subprogram. Note the special check for the names of controlled
14600 -- operations, which are currently exempted from being inherited with
14601 -- a hidden name because they must be findable for generation of
14602 -- implicit run-time calls.
14604 if not Is_Hidden (Parent_Subp)
14605 or else Is_Internal (Parent_Subp)
14606 or else Is_Private_Overriding
14607 or else Is_Internal_Name (Chars (Parent_Subp))
14608 or else Nam_In (Chars (Parent_Subp), Name_Initialize,
14614 -- An inherited dispatching equality will be overridden by an internally
14615 -- generated one, or by an explicit one, so preserve its name and thus
14616 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
14617 -- private operation it may become invisible if the full view has
14618 -- progenitors, and the dispatch table will be malformed.
14619 -- We check that the type is limited to handle the anomalous declaration
14620 -- of Limited_Controlled, which is derived from a non-limited type, and
14621 -- which is handled specially elsewhere as well.
14623 elsif Chars (Parent_Subp) = Name_Op_Eq
14624 and then Is_Dispatching_Operation (Parent_Subp)
14625 and then Etype (Parent_Subp) = Standard_Boolean
14626 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
14628 Etype (First_Formal (Parent_Subp)) =
14629 Etype (Next_Formal (First_Formal (Parent_Subp)))
14633 -- If parent is hidden, this can be a regular derivation if the
14634 -- parent is immediately visible in a non-instantiating context,
14635 -- or if we are in the private part of an instance. This test
14636 -- should still be refined ???
14638 -- The test for In_Instance_Not_Visible avoids inheriting the derived
14639 -- operation as a non-visible operation in cases where the parent
14640 -- subprogram might not be visible now, but was visible within the
14641 -- original generic, so it would be wrong to make the inherited
14642 -- subprogram non-visible now. (Not clear if this test is fully
14643 -- correct; are there any cases where we should declare the inherited
14644 -- operation as not visible to avoid it being overridden, e.g., when
14645 -- the parent type is a generic actual with private primitives ???)
14647 -- (they should be treated the same as other private inherited
14648 -- subprograms, but it's not clear how to do this cleanly). ???
14650 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
14651 and then Is_Immediately_Visible (Parent_Subp)
14652 and then not In_Instance)
14653 or else In_Instance_Not_Visible
14657 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
14658 -- overrides an interface primitive because interface primitives
14659 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
14661 elsif Ada_Version >= Ada_2005
14662 and then Is_Dispatching_Operation (Parent_Subp)
14663 and then Covers_Some_Interface (Parent_Subp)
14667 -- Otherwise, the type is inheriting a private operation, so enter
14668 -- it with a special name so it can't be overridden.
14671 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
14674 Set_Parent (New_Subp, Parent (Derived_Type));
14676 if Present (Actual_Subp) then
14677 Replace_Type (Actual_Subp, New_Subp);
14679 Replace_Type (Parent_Subp, New_Subp);
14682 Conditional_Delay (New_Subp, Parent_Subp);
14684 -- If we are creating a renaming for a primitive operation of an
14685 -- actual of a generic derived type, we must examine the signature
14686 -- of the actual primitive, not that of the generic formal, which for
14687 -- example may be an interface. However the name and initial value
14688 -- of the inherited operation are those of the formal primitive.
14690 Formal := First_Formal (Parent_Subp);
14692 if Present (Actual_Subp) then
14693 Formal_Of_Actual := First_Formal (Actual_Subp);
14695 Formal_Of_Actual := Empty;
14698 while Present (Formal) loop
14699 New_Formal := New_Copy (Formal);
14701 -- Normally we do not go copying parents, but in the case of
14702 -- formals, we need to link up to the declaration (which is the
14703 -- parameter specification), and it is fine to link up to the
14704 -- original formal's parameter specification in this case.
14706 Set_Parent (New_Formal, Parent (Formal));
14707 Append_Entity (New_Formal, New_Subp);
14709 if Present (Formal_Of_Actual) then
14710 Replace_Type (Formal_Of_Actual, New_Formal);
14711 Next_Formal (Formal_Of_Actual);
14713 Replace_Type (Formal, New_Formal);
14716 Next_Formal (Formal);
14719 -- If this derivation corresponds to a tagged generic actual, then
14720 -- primitive operations rename those of the actual. Otherwise the
14721 -- primitive operations rename those of the parent type, If the parent
14722 -- renames an intrinsic operator, so does the new subprogram. We except
14723 -- concatenation, which is always properly typed, and does not get
14724 -- expanded as other intrinsic operations.
14726 if No (Actual_Subp) then
14727 if Is_Intrinsic_Subprogram (Parent_Subp) then
14728 Set_Is_Intrinsic_Subprogram (New_Subp);
14730 if Present (Alias (Parent_Subp))
14731 and then Chars (Parent_Subp) /= Name_Op_Concat
14733 Set_Alias (New_Subp, Alias (Parent_Subp));
14735 Set_Alias (New_Subp, Parent_Subp);
14739 Set_Alias (New_Subp, Parent_Subp);
14743 Set_Alias (New_Subp, Actual_Subp);
14746 -- Inherit the "ghostness" from the parent subprogram
14748 if Is_Ghost_Entity (Alias (New_Subp)) then
14749 Set_Is_Ghost_Entity (New_Subp);
14752 -- Derived subprograms of a tagged type must inherit the convention
14753 -- of the parent subprogram (a requirement of AI-117). Derived
14754 -- subprograms of untagged types simply get convention Ada by default.
14756 -- If the derived type is a tagged generic formal type with unknown
14757 -- discriminants, its convention is intrinsic (RM 6.3.1 (8)).
14759 -- However, if the type is derived from a generic formal, the further
14760 -- inherited subprogram has the convention of the non-generic ancestor.
14761 -- Otherwise there would be no way to override the operation.
14762 -- (This is subject to forthcoming ARG discussions).
14764 if Is_Tagged_Type (Derived_Type) then
14765 if Is_Generic_Type (Derived_Type)
14766 and then Has_Unknown_Discriminants (Derived_Type)
14768 Set_Convention (New_Subp, Convention_Intrinsic);
14771 if Is_Generic_Type (Parent_Type)
14772 and then Has_Unknown_Discriminants (Parent_Type)
14774 Set_Convention (New_Subp, Convention (Alias (Parent_Subp)));
14776 Set_Convention (New_Subp, Convention (Parent_Subp));
14781 -- Predefined controlled operations retain their name even if the parent
14782 -- is hidden (see above), but they are not primitive operations if the
14783 -- ancestor is not visible, for example if the parent is a private
14784 -- extension completed with a controlled extension. Note that a full
14785 -- type that is controlled can break privacy: the flag Is_Controlled is
14786 -- set on both views of the type.
14788 if Is_Controlled (Parent_Type)
14789 and then Nam_In (Chars (Parent_Subp), Name_Initialize,
14792 and then Is_Hidden (Parent_Subp)
14793 and then not Is_Visibly_Controlled (Parent_Type)
14795 Set_Is_Hidden (New_Subp);
14798 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
14799 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
14801 if Ekind (Parent_Subp) = E_Procedure then
14802 Set_Is_Valued_Procedure
14803 (New_Subp, Is_Valued_Procedure (Parent_Subp));
14805 Set_Has_Controlling_Result
14806 (New_Subp, Has_Controlling_Result (Parent_Subp));
14809 -- No_Return must be inherited properly. If this is overridden in the
14810 -- case of a dispatching operation, then a check is made in Sem_Disp
14811 -- that the overriding operation is also No_Return (no such check is
14812 -- required for the case of non-dispatching operation.
14814 Set_No_Return (New_Subp, No_Return (Parent_Subp));
14816 -- A derived function with a controlling result is abstract. If the
14817 -- Derived_Type is a nonabstract formal generic derived type, then
14818 -- inherited operations are not abstract: the required check is done at
14819 -- instantiation time. If the derivation is for a generic actual, the
14820 -- function is not abstract unless the actual is.
14822 if Is_Generic_Type (Derived_Type)
14823 and then not Is_Abstract_Type (Derived_Type)
14827 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
14828 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
14830 -- A subprogram subject to pragma Extensions_Visible with value False
14831 -- requires overriding if the subprogram has at least one controlling
14832 -- OUT parameter (SPARK RM 6.1.7(6)).
14834 elsif Ada_Version >= Ada_2005
14835 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14836 or else (Is_Tagged_Type (Derived_Type)
14837 and then Etype (New_Subp) = Derived_Type
14838 and then not Is_Null_Extension (Derived_Type))
14839 or else (Is_Tagged_Type (Derived_Type)
14840 and then Ekind (Etype (New_Subp)) =
14841 E_Anonymous_Access_Type
14842 and then Designated_Type (Etype (New_Subp)) =
14844 and then not Is_Null_Extension (Derived_Type))
14845 or else (Comes_From_Source (Alias (New_Subp))
14846 and then Is_EVF_Procedure (Alias (New_Subp))))
14847 and then No (Actual_Subp)
14849 if not Is_Tagged_Type (Derived_Type)
14850 or else Is_Abstract_Type (Derived_Type)
14851 or else Is_Abstract_Subprogram (Alias (New_Subp))
14853 Set_Is_Abstract_Subprogram (New_Subp);
14855 Set_Requires_Overriding (New_Subp);
14858 elsif Ada_Version < Ada_2005
14859 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14860 or else (Is_Tagged_Type (Derived_Type)
14861 and then Etype (New_Subp) = Derived_Type
14862 and then No (Actual_Subp)))
14864 Set_Is_Abstract_Subprogram (New_Subp);
14866 -- AI05-0097 : an inherited operation that dispatches on result is
14867 -- abstract if the derived type is abstract, even if the parent type
14868 -- is concrete and the derived type is a null extension.
14870 elsif Has_Controlling_Result (Alias (New_Subp))
14871 and then Is_Abstract_Type (Etype (New_Subp))
14873 Set_Is_Abstract_Subprogram (New_Subp);
14875 -- Finally, if the parent type is abstract we must verify that all
14876 -- inherited operations are either non-abstract or overridden, or that
14877 -- the derived type itself is abstract (this check is performed at the
14878 -- end of a package declaration, in Check_Abstract_Overriding). A
14879 -- private overriding in the parent type will not be visible in the
14880 -- derivation if we are not in an inner package or in a child unit of
14881 -- the parent type, in which case the abstractness of the inherited
14882 -- operation is carried to the new subprogram.
14884 elsif Is_Abstract_Type (Parent_Type)
14885 and then not In_Open_Scopes (Scope (Parent_Type))
14886 and then Is_Private_Overriding
14887 and then Is_Abstract_Subprogram (Visible_Subp)
14889 if No (Actual_Subp) then
14890 Set_Alias (New_Subp, Visible_Subp);
14891 Set_Is_Abstract_Subprogram (New_Subp, True);
14894 -- If this is a derivation for an instance of a formal derived
14895 -- type, abstractness comes from the primitive operation of the
14896 -- actual, not from the operation inherited from the ancestor.
14898 Set_Is_Abstract_Subprogram
14899 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
14903 New_Overloaded_Entity (New_Subp, Derived_Type);
14905 -- Check for case of a derived subprogram for the instantiation of a
14906 -- formal derived tagged type, if so mark the subprogram as dispatching
14907 -- and inherit the dispatching attributes of the actual subprogram. The
14908 -- derived subprogram is effectively renaming of the actual subprogram,
14909 -- so it needs to have the same attributes as the actual.
14911 if Present (Actual_Subp)
14912 and then Is_Dispatching_Operation (Actual_Subp)
14914 Set_Is_Dispatching_Operation (New_Subp);
14916 if Present (DTC_Entity (Actual_Subp)) then
14917 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
14918 Set_DT_Position_Value (New_Subp, DT_Position (Actual_Subp));
14922 -- Indicate that a derived subprogram does not require a body and that
14923 -- it does not require processing of default expressions.
14925 Set_Has_Completion (New_Subp);
14926 Set_Default_Expressions_Processed (New_Subp);
14928 if Ekind (New_Subp) = E_Function then
14929 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
14931 end Derive_Subprogram;
14933 ------------------------
14934 -- Derive_Subprograms --
14935 ------------------------
14937 procedure Derive_Subprograms
14938 (Parent_Type : Entity_Id;
14939 Derived_Type : Entity_Id;
14940 Generic_Actual : Entity_Id := Empty)
14942 Op_List : constant Elist_Id :=
14943 Collect_Primitive_Operations (Parent_Type);
14945 function Check_Derived_Type return Boolean;
14946 -- Check that all the entities derived from Parent_Type are found in
14947 -- the list of primitives of Derived_Type exactly in the same order.
14949 procedure Derive_Interface_Subprogram
14950 (New_Subp : in out Entity_Id;
14952 Actual_Subp : Entity_Id);
14953 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
14954 -- (which is an interface primitive). If Generic_Actual is present then
14955 -- Actual_Subp is the actual subprogram corresponding with the generic
14956 -- subprogram Subp.
14958 function Check_Derived_Type return Boolean is
14962 New_Subp : Entity_Id;
14967 -- Traverse list of entities in the current scope searching for
14968 -- an incomplete type whose full-view is derived type
14970 E := First_Entity (Scope (Derived_Type));
14971 while Present (E) and then E /= Derived_Type loop
14972 if Ekind (E) = E_Incomplete_Type
14973 and then Present (Full_View (E))
14974 and then Full_View (E) = Derived_Type
14976 -- Disable this test if Derived_Type completes an incomplete
14977 -- type because in such case more primitives can be added
14978 -- later to the list of primitives of Derived_Type by routine
14979 -- Process_Incomplete_Dependents
14984 E := Next_Entity (E);
14987 List := Collect_Primitive_Operations (Derived_Type);
14988 Elmt := First_Elmt (List);
14990 Op_Elmt := First_Elmt (Op_List);
14991 while Present (Op_Elmt) loop
14992 Subp := Node (Op_Elmt);
14993 New_Subp := Node (Elmt);
14995 -- At this early stage Derived_Type has no entities with attribute
14996 -- Interface_Alias. In addition, such primitives are always
14997 -- located at the end of the list of primitives of Parent_Type.
14998 -- Therefore, if found we can safely stop processing pending
15001 exit when Present (Interface_Alias (Subp));
15003 -- Handle hidden entities
15005 if not Is_Predefined_Dispatching_Operation (Subp)
15006 and then Is_Hidden (Subp)
15008 if Present (New_Subp)
15009 and then Primitive_Names_Match (Subp, New_Subp)
15015 if not Present (New_Subp)
15016 or else Ekind (Subp) /= Ekind (New_Subp)
15017 or else not Primitive_Names_Match (Subp, New_Subp)
15025 Next_Elmt (Op_Elmt);
15029 end Check_Derived_Type;
15031 ---------------------------------
15032 -- Derive_Interface_Subprogram --
15033 ---------------------------------
15035 procedure Derive_Interface_Subprogram
15036 (New_Subp : in out Entity_Id;
15038 Actual_Subp : Entity_Id)
15040 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
15041 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
15044 pragma Assert (Is_Interface (Iface_Type));
15047 (New_Subp => New_Subp,
15048 Parent_Subp => Iface_Subp,
15049 Derived_Type => Derived_Type,
15050 Parent_Type => Iface_Type,
15051 Actual_Subp => Actual_Subp);
15053 -- Given that this new interface entity corresponds with a primitive
15054 -- of the parent that was not overridden we must leave it associated
15055 -- with its parent primitive to ensure that it will share the same
15056 -- dispatch table slot when overridden.
15058 if No (Actual_Subp) then
15059 Set_Alias (New_Subp, Subp);
15061 -- For instantiations this is not needed since the previous call to
15062 -- Derive_Subprogram leaves the entity well decorated.
15065 pragma Assert (Alias (New_Subp) = Actual_Subp);
15068 end Derive_Interface_Subprogram;
15072 Alias_Subp : Entity_Id;
15073 Act_List : Elist_Id;
15074 Act_Elmt : Elmt_Id;
15075 Act_Subp : Entity_Id := Empty;
15077 Need_Search : Boolean := False;
15078 New_Subp : Entity_Id := Empty;
15079 Parent_Base : Entity_Id;
15082 -- Start of processing for Derive_Subprograms
15085 if Ekind (Parent_Type) = E_Record_Type_With_Private
15086 and then Has_Discriminants (Parent_Type)
15087 and then Present (Full_View (Parent_Type))
15089 Parent_Base := Full_View (Parent_Type);
15091 Parent_Base := Parent_Type;
15094 if Present (Generic_Actual) then
15095 Act_List := Collect_Primitive_Operations (Generic_Actual);
15096 Act_Elmt := First_Elmt (Act_List);
15098 Act_List := No_Elist;
15099 Act_Elmt := No_Elmt;
15102 -- Derive primitives inherited from the parent. Note that if the generic
15103 -- actual is present, this is not really a type derivation, it is a
15104 -- completion within an instance.
15106 -- Case 1: Derived_Type does not implement interfaces
15108 if not Is_Tagged_Type (Derived_Type)
15109 or else (not Has_Interfaces (Derived_Type)
15110 and then not (Present (Generic_Actual)
15111 and then Has_Interfaces (Generic_Actual)))
15113 Elmt := First_Elmt (Op_List);
15114 while Present (Elmt) loop
15115 Subp := Node (Elmt);
15117 -- Literals are derived earlier in the process of building the
15118 -- derived type, and are skipped here.
15120 if Ekind (Subp) = E_Enumeration_Literal then
15123 -- The actual is a direct descendant and the common primitive
15124 -- operations appear in the same order.
15126 -- If the generic parent type is present, the derived type is an
15127 -- instance of a formal derived type, and within the instance its
15128 -- operations are those of the actual. We derive from the formal
15129 -- type but make the inherited operations aliases of the
15130 -- corresponding operations of the actual.
15133 pragma Assert (No (Node (Act_Elmt))
15134 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
15137 (Subp, Node (Act_Elmt),
15138 Skip_Controlling_Formals => True)));
15141 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
15143 if Present (Act_Elmt) then
15144 Next_Elmt (Act_Elmt);
15151 -- Case 2: Derived_Type implements interfaces
15154 -- If the parent type has no predefined primitives we remove
15155 -- predefined primitives from the list of primitives of generic
15156 -- actual to simplify the complexity of this algorithm.
15158 if Present (Generic_Actual) then
15160 Has_Predefined_Primitives : Boolean := False;
15163 -- Check if the parent type has predefined primitives
15165 Elmt := First_Elmt (Op_List);
15166 while Present (Elmt) loop
15167 Subp := Node (Elmt);
15169 if Is_Predefined_Dispatching_Operation (Subp)
15170 and then not Comes_From_Source (Ultimate_Alias (Subp))
15172 Has_Predefined_Primitives := True;
15179 -- Remove predefined primitives of Generic_Actual. We must use
15180 -- an auxiliary list because in case of tagged types the value
15181 -- returned by Collect_Primitive_Operations is the value stored
15182 -- in its Primitive_Operations attribute (and we don't want to
15183 -- modify its current contents).
15185 if not Has_Predefined_Primitives then
15187 Aux_List : constant Elist_Id := New_Elmt_List;
15190 Elmt := First_Elmt (Act_List);
15191 while Present (Elmt) loop
15192 Subp := Node (Elmt);
15194 if not Is_Predefined_Dispatching_Operation (Subp)
15195 or else Comes_From_Source (Subp)
15197 Append_Elmt (Subp, Aux_List);
15203 Act_List := Aux_List;
15207 Act_Elmt := First_Elmt (Act_List);
15208 Act_Subp := Node (Act_Elmt);
15212 -- Stage 1: If the generic actual is not present we derive the
15213 -- primitives inherited from the parent type. If the generic parent
15214 -- type is present, the derived type is an instance of a formal
15215 -- derived type, and within the instance its operations are those of
15216 -- the actual. We derive from the formal type but make the inherited
15217 -- operations aliases of the corresponding operations of the actual.
15219 Elmt := First_Elmt (Op_List);
15220 while Present (Elmt) loop
15221 Subp := Node (Elmt);
15222 Alias_Subp := Ultimate_Alias (Subp);
15224 -- Do not derive internal entities of the parent that link
15225 -- interface primitives with their covering primitive. These
15226 -- entities will be added to this type when frozen.
15228 if Present (Interface_Alias (Subp)) then
15232 -- If the generic actual is present find the corresponding
15233 -- operation in the generic actual. If the parent type is a
15234 -- direct ancestor of the derived type then, even if it is an
15235 -- interface, the operations are inherited from the primary
15236 -- dispatch table and are in the proper order. If we detect here
15237 -- that primitives are not in the same order we traverse the list
15238 -- of primitive operations of the actual to find the one that
15239 -- implements the interface primitive.
15243 (Present (Generic_Actual)
15244 and then Present (Act_Subp)
15246 (Primitive_Names_Match (Subp, Act_Subp)
15248 Type_Conformant (Subp, Act_Subp,
15249 Skip_Controlling_Formals => True)))
15251 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
15252 Use_Full_View => True));
15254 -- Remember that we need searching for all pending primitives
15256 Need_Search := True;
15258 -- Handle entities associated with interface primitives
15260 if Present (Alias_Subp)
15261 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15262 and then not Is_Predefined_Dispatching_Operation (Subp)
15264 -- Search for the primitive in the homonym chain
15267 Find_Primitive_Covering_Interface
15268 (Tagged_Type => Generic_Actual,
15269 Iface_Prim => Alias_Subp);
15271 -- Previous search may not locate primitives covering
15272 -- interfaces defined in generics units or instantiations.
15273 -- (it fails if the covering primitive has formals whose
15274 -- type is also defined in generics or instantiations).
15275 -- In such case we search in the list of primitives of the
15276 -- generic actual for the internal entity that links the
15277 -- interface primitive and the covering primitive.
15280 and then Is_Generic_Type (Parent_Type)
15282 -- This code has been designed to handle only generic
15283 -- formals that implement interfaces that are defined
15284 -- in a generic unit or instantiation. If this code is
15285 -- needed for other cases we must review it because
15286 -- (given that it relies on Original_Location to locate
15287 -- the primitive of Generic_Actual that covers the
15288 -- interface) it could leave linked through attribute
15289 -- Alias entities of unrelated instantiations).
15293 (Scope (Find_Dispatching_Type (Alias_Subp)))
15295 Instantiation_Depth
15296 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
15299 Iface_Prim_Loc : constant Source_Ptr :=
15300 Original_Location (Sloc (Alias_Subp));
15307 First_Elmt (Primitive_Operations (Generic_Actual));
15309 Search : while Present (Elmt) loop
15310 Prim := Node (Elmt);
15312 if Present (Interface_Alias (Prim))
15313 and then Original_Location
15314 (Sloc (Interface_Alias (Prim))) =
15317 Act_Subp := Alias (Prim);
15326 pragma Assert (Present (Act_Subp)
15327 or else Is_Abstract_Type (Generic_Actual)
15328 or else Serious_Errors_Detected > 0);
15330 -- Handle predefined primitives plus the rest of user-defined
15334 Act_Elmt := First_Elmt (Act_List);
15335 while Present (Act_Elmt) loop
15336 Act_Subp := Node (Act_Elmt);
15338 exit when Primitive_Names_Match (Subp, Act_Subp)
15339 and then Type_Conformant
15341 Skip_Controlling_Formals => True)
15342 and then No (Interface_Alias (Act_Subp));
15344 Next_Elmt (Act_Elmt);
15347 if No (Act_Elmt) then
15353 -- Case 1: If the parent is a limited interface then it has the
15354 -- predefined primitives of synchronized interfaces. However, the
15355 -- actual type may be a non-limited type and hence it does not
15356 -- have such primitives.
15358 if Present (Generic_Actual)
15359 and then not Present (Act_Subp)
15360 and then Is_Limited_Interface (Parent_Base)
15361 and then Is_Predefined_Interface_Primitive (Subp)
15365 -- Case 2: Inherit entities associated with interfaces that were
15366 -- not covered by the parent type. We exclude here null interface
15367 -- primitives because they do not need special management.
15369 -- We also exclude interface operations that are renamings. If the
15370 -- subprogram is an explicit renaming of an interface primitive,
15371 -- it is a regular primitive operation, and the presence of its
15372 -- alias is not relevant: it has to be derived like any other
15375 elsif Present (Alias (Subp))
15376 and then Nkind (Unit_Declaration_Node (Subp)) /=
15377 N_Subprogram_Renaming_Declaration
15378 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15380 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
15381 and then Null_Present (Parent (Alias_Subp)))
15383 -- If this is an abstract private type then we transfer the
15384 -- derivation of the interface primitive from the partial view
15385 -- to the full view. This is safe because all the interfaces
15386 -- must be visible in the partial view. Done to avoid adding
15387 -- a new interface derivation to the private part of the
15388 -- enclosing package; otherwise this new derivation would be
15389 -- decorated as hidden when the analysis of the enclosing
15390 -- package completes.
15392 if Is_Abstract_Type (Derived_Type)
15393 and then In_Private_Part (Current_Scope)
15394 and then Has_Private_Declaration (Derived_Type)
15397 Partial_View : Entity_Id;
15402 Partial_View := First_Entity (Current_Scope);
15404 exit when No (Partial_View)
15405 or else (Has_Private_Declaration (Partial_View)
15407 Full_View (Partial_View) = Derived_Type);
15409 Next_Entity (Partial_View);
15412 -- If the partial view was not found then the source code
15413 -- has errors and the derivation is not needed.
15415 if Present (Partial_View) then
15417 First_Elmt (Primitive_Operations (Partial_View));
15418 while Present (Elmt) loop
15419 Ent := Node (Elmt);
15421 if Present (Alias (Ent))
15422 and then Ultimate_Alias (Ent) = Alias (Subp)
15425 (Ent, Primitive_Operations (Derived_Type));
15432 -- If the interface primitive was not found in the
15433 -- partial view then this interface primitive was
15434 -- overridden. We add a derivation to activate in
15435 -- Derive_Progenitor_Subprograms the machinery to
15439 Derive_Interface_Subprogram
15440 (New_Subp => New_Subp,
15442 Actual_Subp => Act_Subp);
15447 Derive_Interface_Subprogram
15448 (New_Subp => New_Subp,
15450 Actual_Subp => Act_Subp);
15453 -- Case 3: Common derivation
15457 (New_Subp => New_Subp,
15458 Parent_Subp => Subp,
15459 Derived_Type => Derived_Type,
15460 Parent_Type => Parent_Base,
15461 Actual_Subp => Act_Subp);
15464 -- No need to update Act_Elm if we must search for the
15465 -- corresponding operation in the generic actual
15468 and then Present (Act_Elmt)
15470 Next_Elmt (Act_Elmt);
15471 Act_Subp := Node (Act_Elmt);
15478 -- Inherit additional operations from progenitors. If the derived
15479 -- type is a generic actual, there are not new primitive operations
15480 -- for the type because it has those of the actual, and therefore
15481 -- nothing needs to be done. The renamings generated above are not
15482 -- primitive operations, and their purpose is simply to make the
15483 -- proper operations visible within an instantiation.
15485 if No (Generic_Actual) then
15486 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
15490 -- Final check: Direct descendants must have their primitives in the
15491 -- same order. We exclude from this test untagged types and instances
15492 -- of formal derived types. We skip this test if we have already
15493 -- reported serious errors in the sources.
15495 pragma Assert (not Is_Tagged_Type (Derived_Type)
15496 or else Present (Generic_Actual)
15497 or else Serious_Errors_Detected > 0
15498 or else Check_Derived_Type);
15499 end Derive_Subprograms;
15501 --------------------------------
15502 -- Derived_Standard_Character --
15503 --------------------------------
15505 procedure Derived_Standard_Character
15507 Parent_Type : Entity_Id;
15508 Derived_Type : Entity_Id)
15510 Loc : constant Source_Ptr := Sloc (N);
15511 Def : constant Node_Id := Type_Definition (N);
15512 Indic : constant Node_Id := Subtype_Indication (Def);
15513 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
15514 Implicit_Base : constant Entity_Id :=
15516 (E_Enumeration_Type, N, Derived_Type, 'B');
15522 Discard_Node (Process_Subtype (Indic, N));
15524 Set_Etype (Implicit_Base, Parent_Base);
15525 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
15526 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
15528 Set_Is_Character_Type (Implicit_Base, True);
15529 Set_Has_Delayed_Freeze (Implicit_Base);
15531 -- The bounds of the implicit base are the bounds of the parent base.
15532 -- Note that their type is the parent base.
15534 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
15535 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
15537 Set_Scalar_Range (Implicit_Base,
15540 High_Bound => Hi));
15542 Conditional_Delay (Derived_Type, Parent_Type);
15544 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
15545 Set_Etype (Derived_Type, Implicit_Base);
15546 Set_Size_Info (Derived_Type, Parent_Type);
15548 if Unknown_RM_Size (Derived_Type) then
15549 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
15552 Set_Is_Character_Type (Derived_Type, True);
15554 if Nkind (Indic) /= N_Subtype_Indication then
15556 -- If no explicit constraint, the bounds are those
15557 -- of the parent type.
15559 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
15560 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
15561 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
15564 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
15566 -- Because the implicit base is used in the conversion of the bounds, we
15567 -- have to freeze it now. This is similar to what is done for numeric
15568 -- types, and it equally suspicious, but otherwise a non-static bound
15569 -- will have a reference to an unfrozen type, which is rejected by Gigi
15570 -- (???). This requires specific care for definition of stream
15571 -- attributes. For details, see comments at the end of
15572 -- Build_Derived_Numeric_Type.
15574 Freeze_Before (N, Implicit_Base);
15575 end Derived_Standard_Character;
15577 ------------------------------
15578 -- Derived_Type_Declaration --
15579 ------------------------------
15581 procedure Derived_Type_Declaration
15584 Is_Completion : Boolean)
15586 Parent_Type : Entity_Id;
15588 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
15589 -- Check whether the parent type is a generic formal, or derives
15590 -- directly or indirectly from one.
15592 ------------------------
15593 -- Comes_From_Generic --
15594 ------------------------
15596 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
15598 if Is_Generic_Type (Typ) then
15601 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
15604 elsif Is_Private_Type (Typ)
15605 and then Present (Full_View (Typ))
15606 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
15610 elsif Is_Generic_Actual_Type (Typ) then
15616 end Comes_From_Generic;
15620 Def : constant Node_Id := Type_Definition (N);
15621 Iface_Def : Node_Id;
15622 Indic : constant Node_Id := Subtype_Indication (Def);
15623 Extension : constant Node_Id := Record_Extension_Part (Def);
15624 Parent_Node : Node_Id;
15627 -- Start of processing for Derived_Type_Declaration
15630 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
15632 -- Ada 2005 (AI-251): In case of interface derivation check that the
15633 -- parent is also an interface.
15635 if Interface_Present (Def) then
15636 Check_SPARK_05_Restriction ("interface is not allowed", Def);
15638 if not Is_Interface (Parent_Type) then
15639 Diagnose_Interface (Indic, Parent_Type);
15642 Parent_Node := Parent (Base_Type (Parent_Type));
15643 Iface_Def := Type_Definition (Parent_Node);
15645 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
15646 -- other limited interfaces.
15648 if Limited_Present (Def) then
15649 if Limited_Present (Iface_Def) then
15652 elsif Protected_Present (Iface_Def) then
15654 ("descendant of& must be declared"
15655 & " as a protected interface",
15658 elsif Synchronized_Present (Iface_Def) then
15660 ("descendant of& must be declared"
15661 & " as a synchronized interface",
15664 elsif Task_Present (Iface_Def) then
15666 ("descendant of& must be declared as a task interface",
15671 ("(Ada 2005) limited interface cannot "
15672 & "inherit from non-limited interface", Indic);
15675 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
15676 -- from non-limited or limited interfaces.
15678 elsif not Protected_Present (Def)
15679 and then not Synchronized_Present (Def)
15680 and then not Task_Present (Def)
15682 if Limited_Present (Iface_Def) then
15685 elsif Protected_Present (Iface_Def) then
15687 ("descendant of& must be declared"
15688 & " as a protected interface",
15691 elsif Synchronized_Present (Iface_Def) then
15693 ("descendant of& must be declared"
15694 & " as a synchronized interface",
15697 elsif Task_Present (Iface_Def) then
15699 ("descendant of& must be declared as a task interface",
15708 if Is_Tagged_Type (Parent_Type)
15709 and then Is_Concurrent_Type (Parent_Type)
15710 and then not Is_Interface (Parent_Type)
15713 ("parent type of a record extension cannot be "
15714 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
15715 Set_Etype (T, Any_Type);
15719 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
15722 if Is_Tagged_Type (Parent_Type)
15723 and then Is_Non_Empty_List (Interface_List (Def))
15730 Intf := First (Interface_List (Def));
15731 while Present (Intf) loop
15732 T := Find_Type_Of_Subtype_Indic (Intf);
15734 if not Is_Interface (T) then
15735 Diagnose_Interface (Intf, T);
15737 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
15738 -- a limited type from having a nonlimited progenitor.
15740 elsif (Limited_Present (Def)
15741 or else (not Is_Interface (Parent_Type)
15742 and then Is_Limited_Type (Parent_Type)))
15743 and then not Is_Limited_Interface (T)
15746 ("progenitor interface& of limited type must be limited",
15755 if Parent_Type = Any_Type
15756 or else Etype (Parent_Type) = Any_Type
15757 or else (Is_Class_Wide_Type (Parent_Type)
15758 and then Etype (Parent_Type) = T)
15760 -- If Parent_Type is undefined or illegal, make new type into a
15761 -- subtype of Any_Type, and set a few attributes to prevent cascaded
15762 -- errors. If this is a self-definition, emit error now.
15764 if T = Parent_Type or else T = Etype (Parent_Type) then
15765 Error_Msg_N ("type cannot be used in its own definition", Indic);
15768 Set_Ekind (T, Ekind (Parent_Type));
15769 Set_Etype (T, Any_Type);
15770 Set_Scalar_Range (T, Scalar_Range (Any_Type));
15772 if Is_Tagged_Type (T)
15773 and then Is_Record_Type (T)
15775 Set_Direct_Primitive_Operations (T, New_Elmt_List);
15781 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
15782 -- an interface is special because the list of interfaces in the full
15783 -- view can be given in any order. For example:
15785 -- type A is interface;
15786 -- type B is interface and A;
15787 -- type D is new B with private;
15789 -- type D is new A and B with null record; -- 1 --
15791 -- In this case we perform the following transformation of -1-:
15793 -- type D is new B and A with null record;
15795 -- If the parent of the full-view covers the parent of the partial-view
15796 -- we have two possible cases:
15798 -- 1) They have the same parent
15799 -- 2) The parent of the full-view implements some further interfaces
15801 -- In both cases we do not need to perform the transformation. In the
15802 -- first case the source program is correct and the transformation is
15803 -- not needed; in the second case the source program does not fulfill
15804 -- the no-hidden interfaces rule (AI-396) and the error will be reported
15807 -- This transformation not only simplifies the rest of the analysis of
15808 -- this type declaration but also simplifies the correct generation of
15809 -- the object layout to the expander.
15811 if In_Private_Part (Current_Scope)
15812 and then Is_Interface (Parent_Type)
15816 Partial_View : Entity_Id;
15817 Partial_View_Parent : Entity_Id;
15818 New_Iface : Node_Id;
15821 -- Look for the associated private type declaration
15823 Partial_View := First_Entity (Current_Scope);
15825 exit when No (Partial_View)
15826 or else (Has_Private_Declaration (Partial_View)
15827 and then Full_View (Partial_View) = T);
15829 Next_Entity (Partial_View);
15832 -- If the partial view was not found then the source code has
15833 -- errors and the transformation is not needed.
15835 if Present (Partial_View) then
15836 Partial_View_Parent := Etype (Partial_View);
15838 -- If the parent of the full-view covers the parent of the
15839 -- partial-view we have nothing else to do.
15841 if Interface_Present_In_Ancestor
15842 (Parent_Type, Partial_View_Parent)
15846 -- Traverse the list of interfaces of the full-view to look
15847 -- for the parent of the partial-view and perform the tree
15851 Iface := First (Interface_List (Def));
15852 while Present (Iface) loop
15853 if Etype (Iface) = Etype (Partial_View) then
15854 Rewrite (Subtype_Indication (Def),
15855 New_Copy (Subtype_Indication
15856 (Parent (Partial_View))));
15859 Make_Identifier (Sloc (N), Chars (Parent_Type));
15860 Append (New_Iface, Interface_List (Def));
15862 -- Analyze the transformed code
15864 Derived_Type_Declaration (T, N, Is_Completion);
15875 -- Only composite types other than array types are allowed to have
15878 if Present (Discriminant_Specifications (N)) then
15879 if (Is_Elementary_Type (Parent_Type)
15881 Is_Array_Type (Parent_Type))
15882 and then not Error_Posted (N)
15885 ("elementary or array type cannot have discriminants",
15886 Defining_Identifier (First (Discriminant_Specifications (N))));
15887 Set_Has_Discriminants (T, False);
15889 -- The type is allowed to have discriminants
15892 Check_SPARK_05_Restriction ("discriminant type is not allowed", N);
15896 -- In Ada 83, a derived type defined in a package specification cannot
15897 -- be used for further derivation until the end of its visible part.
15898 -- Note that derivation in the private part of the package is allowed.
15900 if Ada_Version = Ada_83
15901 and then Is_Derived_Type (Parent_Type)
15902 and then In_Visible_Part (Scope (Parent_Type))
15904 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
15906 ("(Ada 83): premature use of type for derivation", Indic);
15910 -- Check for early use of incomplete or private type
15912 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
15913 Error_Msg_N ("premature derivation of incomplete type", Indic);
15916 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
15917 and then not Comes_From_Generic (Parent_Type))
15918 or else Has_Private_Component (Parent_Type)
15920 -- The ancestor type of a formal type can be incomplete, in which
15921 -- case only the operations of the partial view are available in the
15922 -- generic. Subsequent checks may be required when the full view is
15923 -- analyzed to verify that a derivation from a tagged type has an
15926 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
15929 elsif No (Underlying_Type (Parent_Type))
15930 or else Has_Private_Component (Parent_Type)
15933 ("premature derivation of derived or private type", Indic);
15935 -- Flag the type itself as being in error, this prevents some
15936 -- nasty problems with subsequent uses of the malformed type.
15938 Set_Error_Posted (T);
15940 -- Check that within the immediate scope of an untagged partial
15941 -- view it's illegal to derive from the partial view if the
15942 -- full view is tagged. (7.3(7))
15944 -- We verify that the Parent_Type is a partial view by checking
15945 -- that it is not a Full_Type_Declaration (i.e. a private type or
15946 -- private extension declaration), to distinguish a partial view
15947 -- from a derivation from a private type which also appears as
15948 -- E_Private_Type. If the parent base type is not declared in an
15949 -- enclosing scope there is no need to check.
15951 elsif Present (Full_View (Parent_Type))
15952 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
15953 and then not Is_Tagged_Type (Parent_Type)
15954 and then Is_Tagged_Type (Full_View (Parent_Type))
15955 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
15958 ("premature derivation from type with tagged full view",
15963 -- Check that form of derivation is appropriate
15965 Taggd := Is_Tagged_Type (Parent_Type);
15967 -- Set the parent type to the class-wide type's specific type in this
15968 -- case to prevent cascading errors
15970 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
15971 Error_Msg_N ("parent type must not be a class-wide type", Indic);
15972 Set_Etype (T, Etype (Parent_Type));
15976 if Present (Extension) and then not Taggd then
15978 ("type derived from untagged type cannot have extension", Indic);
15980 elsif No (Extension) and then Taggd then
15982 -- If this declaration is within a private part (or body) of a
15983 -- generic instantiation then the derivation is allowed (the parent
15984 -- type can only appear tagged in this case if it's a generic actual
15985 -- type, since it would otherwise have been rejected in the analysis
15986 -- of the generic template).
15988 if not Is_Generic_Actual_Type (Parent_Type)
15989 or else In_Visible_Part (Scope (Parent_Type))
15991 if Is_Class_Wide_Type (Parent_Type) then
15993 ("parent type must not be a class-wide type", Indic);
15995 -- Use specific type to prevent cascaded errors.
15997 Parent_Type := Etype (Parent_Type);
16001 ("type derived from tagged type must have extension", Indic);
16006 -- AI-443: Synchronized formal derived types require a private
16007 -- extension. There is no point in checking the ancestor type or
16008 -- the progenitors since the construct is wrong to begin with.
16010 if Ada_Version >= Ada_2005
16011 and then Is_Generic_Type (T)
16012 and then Present (Original_Node (N))
16015 Decl : constant Node_Id := Original_Node (N);
16018 if Nkind (Decl) = N_Formal_Type_Declaration
16019 and then Nkind (Formal_Type_Definition (Decl)) =
16020 N_Formal_Derived_Type_Definition
16021 and then Synchronized_Present (Formal_Type_Definition (Decl))
16022 and then No (Extension)
16024 -- Avoid emitting a duplicate error message
16026 and then not Error_Posted (Indic)
16029 ("synchronized derived type must have extension", N);
16034 if Null_Exclusion_Present (Def)
16035 and then not Is_Access_Type (Parent_Type)
16037 Error_Msg_N ("null exclusion can only apply to an access type", N);
16040 -- Avoid deriving parent primitives of underlying record views
16042 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
16043 Derive_Subps => not Is_Underlying_Record_View (T));
16045 -- AI-419: The parent type of an explicitly limited derived type must
16046 -- be a limited type or a limited interface.
16048 if Limited_Present (Def) then
16049 Set_Is_Limited_Record (T);
16051 if Is_Interface (T) then
16052 Set_Is_Limited_Interface (T);
16055 if not Is_Limited_Type (Parent_Type)
16057 (not Is_Interface (Parent_Type)
16058 or else not Is_Limited_Interface (Parent_Type))
16060 -- AI05-0096: a derivation in the private part of an instance is
16061 -- legal if the generic formal is untagged limited, and the actual
16064 if Is_Generic_Actual_Type (Parent_Type)
16065 and then In_Private_Part (Current_Scope)
16068 (Generic_Parent_Type (Parent (Parent_Type)))
16074 ("parent type& of limited type must be limited",
16080 -- In SPARK, there are no derived type definitions other than type
16081 -- extensions of tagged record types.
16083 if No (Extension) then
16084 Check_SPARK_05_Restriction
16085 ("derived type is not allowed", Original_Node (N));
16087 end Derived_Type_Declaration;
16089 ------------------------
16090 -- Diagnose_Interface --
16091 ------------------------
16093 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
16095 if not Is_Interface (E) and then E /= Any_Type then
16096 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
16098 end Diagnose_Interface;
16100 ----------------------------------
16101 -- Enumeration_Type_Declaration --
16102 ----------------------------------
16104 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16111 -- Create identifier node representing lower bound
16113 B_Node := New_Node (N_Identifier, Sloc (Def));
16114 L := First (Literals (Def));
16115 Set_Chars (B_Node, Chars (L));
16116 Set_Entity (B_Node, L);
16117 Set_Etype (B_Node, T);
16118 Set_Is_Static_Expression (B_Node, True);
16120 R_Node := New_Node (N_Range, Sloc (Def));
16121 Set_Low_Bound (R_Node, B_Node);
16123 Set_Ekind (T, E_Enumeration_Type);
16124 Set_First_Literal (T, L);
16126 Set_Is_Constrained (T);
16130 -- Loop through literals of enumeration type setting pos and rep values
16131 -- except that if the Ekind is already set, then it means the literal
16132 -- was already constructed (case of a derived type declaration and we
16133 -- should not disturb the Pos and Rep values.
16135 while Present (L) loop
16136 if Ekind (L) /= E_Enumeration_Literal then
16137 Set_Ekind (L, E_Enumeration_Literal);
16138 Set_Enumeration_Pos (L, Ev);
16139 Set_Enumeration_Rep (L, Ev);
16140 Set_Is_Known_Valid (L, True);
16144 New_Overloaded_Entity (L);
16145 Generate_Definition (L);
16146 Set_Convention (L, Convention_Intrinsic);
16148 -- Case of character literal
16150 if Nkind (L) = N_Defining_Character_Literal then
16151 Set_Is_Character_Type (T, True);
16153 -- Check violation of No_Wide_Characters
16155 if Restriction_Check_Required (No_Wide_Characters) then
16156 Get_Name_String (Chars (L));
16158 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
16159 Check_Restriction (No_Wide_Characters, L);
16168 -- Now create a node representing upper bound
16170 B_Node := New_Node (N_Identifier, Sloc (Def));
16171 Set_Chars (B_Node, Chars (Last (Literals (Def))));
16172 Set_Entity (B_Node, Last (Literals (Def)));
16173 Set_Etype (B_Node, T);
16174 Set_Is_Static_Expression (B_Node, True);
16176 Set_High_Bound (R_Node, B_Node);
16178 -- Initialize various fields of the type. Some of this information
16179 -- may be overwritten later through rep.clauses.
16181 Set_Scalar_Range (T, R_Node);
16182 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
16183 Set_Enum_Esize (T);
16184 Set_Enum_Pos_To_Rep (T, Empty);
16186 -- Set Discard_Names if configuration pragma set, or if there is
16187 -- a parameterless pragma in the current declarative region
16189 if Global_Discard_Names or else Discard_Names (Scope (T)) then
16190 Set_Discard_Names (T);
16193 -- Process end label if there is one
16195 if Present (Def) then
16196 Process_End_Label (Def, 'e', T);
16198 end Enumeration_Type_Declaration;
16200 ---------------------------------
16201 -- Expand_To_Stored_Constraint --
16202 ---------------------------------
16204 function Expand_To_Stored_Constraint
16206 Constraint : Elist_Id) return Elist_Id
16208 Explicitly_Discriminated_Type : Entity_Id;
16209 Expansion : Elist_Id;
16210 Discriminant : Entity_Id;
16212 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
16213 -- Find the nearest type that actually specifies discriminants
16215 ---------------------------------
16216 -- Type_With_Explicit_Discrims --
16217 ---------------------------------
16219 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
16220 Typ : constant E := Base_Type (Id);
16223 if Ekind (Typ) in Incomplete_Or_Private_Kind then
16224 if Present (Full_View (Typ)) then
16225 return Type_With_Explicit_Discrims (Full_View (Typ));
16229 if Has_Discriminants (Typ) then
16234 if Etype (Typ) = Typ then
16236 elsif Has_Discriminants (Typ) then
16239 return Type_With_Explicit_Discrims (Etype (Typ));
16242 end Type_With_Explicit_Discrims;
16244 -- Start of processing for Expand_To_Stored_Constraint
16247 if No (Constraint) or else Is_Empty_Elmt_List (Constraint) then
16251 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
16253 if No (Explicitly_Discriminated_Type) then
16257 Expansion := New_Elmt_List;
16260 First_Stored_Discriminant (Explicitly_Discriminated_Type);
16261 while Present (Discriminant) loop
16263 (Get_Discriminant_Value
16264 (Discriminant, Explicitly_Discriminated_Type, Constraint),
16266 Next_Stored_Discriminant (Discriminant);
16270 end Expand_To_Stored_Constraint;
16272 ---------------------------
16273 -- Find_Hidden_Interface --
16274 ---------------------------
16276 function Find_Hidden_Interface
16278 Dest : Elist_Id) return Entity_Id
16281 Iface_Elmt : Elmt_Id;
16284 if Present (Src) and then Present (Dest) then
16285 Iface_Elmt := First_Elmt (Src);
16286 while Present (Iface_Elmt) loop
16287 Iface := Node (Iface_Elmt);
16289 if Is_Interface (Iface)
16290 and then not Contain_Interface (Iface, Dest)
16295 Next_Elmt (Iface_Elmt);
16300 end Find_Hidden_Interface;
16302 --------------------
16303 -- Find_Type_Name --
16304 --------------------
16306 function Find_Type_Name (N : Node_Id) return Entity_Id is
16307 Id : constant Entity_Id := Defining_Identifier (N);
16309 New_Id : Entity_Id;
16310 Prev_Par : Node_Id;
16312 procedure Check_Duplicate_Aspects;
16313 -- Check that aspects specified in a completion have not been specified
16314 -- already in the partial view. Type_Invariant and others can be
16315 -- specified on either view but never on both.
16317 procedure Tag_Mismatch;
16318 -- Diagnose a tagged partial view whose full view is untagged.
16319 -- We post the message on the full view, with a reference to
16320 -- the previous partial view. The partial view can be private
16321 -- or incomplete, and these are handled in a different manner,
16322 -- so we determine the position of the error message from the
16323 -- respective slocs of both.
16325 -----------------------------
16326 -- Check_Duplicate_Aspects --
16327 -----------------------------
16328 procedure Check_Duplicate_Aspects is
16329 Prev_Aspects : constant List_Id := Aspect_Specifications (Prev_Par);
16330 Full_Aspects : constant List_Id := Aspect_Specifications (N);
16331 F_Spec, P_Spec : Node_Id;
16334 if Present (Prev_Aspects) and then Present (Full_Aspects) then
16335 F_Spec := First (Full_Aspects);
16336 while Present (F_Spec) loop
16337 P_Spec := First (Prev_Aspects);
16338 while Present (P_Spec) loop
16339 if Chars (Identifier (P_Spec)) = Chars (Identifier (F_Spec))
16342 ("aspect already specified in private declaration",
16354 end Check_Duplicate_Aspects;
16360 procedure Tag_Mismatch is
16362 if Sloc (Prev) < Sloc (Id) then
16363 if Ada_Version >= Ada_2012
16364 and then Nkind (N) = N_Private_Type_Declaration
16367 ("declaration of private } must be a tagged type ", Id, Prev);
16370 ("full declaration of } must be a tagged type ", Id, Prev);
16374 if Ada_Version >= Ada_2012
16375 and then Nkind (N) = N_Private_Type_Declaration
16378 ("declaration of private } must be a tagged type ", Prev, Id);
16381 ("full declaration of } must be a tagged type ", Prev, Id);
16386 -- Start of processing for Find_Type_Name
16389 -- Find incomplete declaration, if one was given
16391 Prev := Current_Entity_In_Scope (Id);
16393 -- New type declaration
16399 -- Previous declaration exists
16402 Prev_Par := Parent (Prev);
16404 -- Error if not incomplete/private case except if previous
16405 -- declaration is implicit, etc. Enter_Name will emit error if
16408 if not Is_Incomplete_Or_Private_Type (Prev) then
16412 -- Check invalid completion of private or incomplete type
16414 elsif not Nkind_In (N, N_Full_Type_Declaration,
16415 N_Task_Type_Declaration,
16416 N_Protected_Type_Declaration)
16418 (Ada_Version < Ada_2012
16419 or else not Is_Incomplete_Type (Prev)
16420 or else not Nkind_In (N, N_Private_Type_Declaration,
16421 N_Private_Extension_Declaration))
16423 -- Completion must be a full type declarations (RM 7.3(4))
16425 Error_Msg_Sloc := Sloc (Prev);
16426 Error_Msg_NE ("invalid completion of }", Id, Prev);
16428 -- Set scope of Id to avoid cascaded errors. Entity is never
16429 -- examined again, except when saving globals in generics.
16431 Set_Scope (Id, Current_Scope);
16434 -- If this is a repeated incomplete declaration, no further
16435 -- checks are possible.
16437 if Nkind (N) = N_Incomplete_Type_Declaration then
16441 -- Case of full declaration of incomplete type
16443 elsif Ekind (Prev) = E_Incomplete_Type
16444 and then (Ada_Version < Ada_2012
16445 or else No (Full_View (Prev))
16446 or else not Is_Private_Type (Full_View (Prev)))
16448 -- Indicate that the incomplete declaration has a matching full
16449 -- declaration. The defining occurrence of the incomplete
16450 -- declaration remains the visible one, and the procedure
16451 -- Get_Full_View dereferences it whenever the type is used.
16453 if Present (Full_View (Prev)) then
16454 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16457 Set_Full_View (Prev, Id);
16458 Append_Entity (Id, Current_Scope);
16459 Set_Is_Public (Id, Is_Public (Prev));
16460 Set_Is_Internal (Id);
16463 -- If the incomplete view is tagged, a class_wide type has been
16464 -- created already. Use it for the private type as well, in order
16465 -- to prevent multiple incompatible class-wide types that may be
16466 -- created for self-referential anonymous access components.
16468 if Is_Tagged_Type (Prev)
16469 and then Present (Class_Wide_Type (Prev))
16471 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
16472 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
16474 -- The type of the classwide type is the current Id. Previously
16475 -- this was not done for private declarations because of order-
16476 -- of elaboration issues in the back-end, but gigi now handles
16479 Set_Etype (Class_Wide_Type (Id), Id);
16482 -- Case of full declaration of private type
16485 -- If the private type was a completion of an incomplete type then
16486 -- update Prev to reference the private type
16488 if Ada_Version >= Ada_2012
16489 and then Ekind (Prev) = E_Incomplete_Type
16490 and then Present (Full_View (Prev))
16491 and then Is_Private_Type (Full_View (Prev))
16493 Prev := Full_View (Prev);
16494 Prev_Par := Parent (Prev);
16497 if Nkind (N) = N_Full_Type_Declaration
16499 (Type_Definition (N), N_Record_Definition,
16500 N_Derived_Type_Definition)
16501 and then Interface_Present (Type_Definition (N))
16504 ("completion of private type cannot be an interface", N);
16507 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
16508 if Etype (Prev) /= Prev then
16510 -- Prev is a private subtype or a derived type, and needs
16513 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16516 elsif Ekind (Prev) = E_Private_Type
16517 and then Nkind_In (N, N_Task_Type_Declaration,
16518 N_Protected_Type_Declaration)
16521 ("completion of nonlimited type cannot be limited", N);
16523 elsif Ekind (Prev) = E_Record_Type_With_Private
16524 and then Nkind_In (N, N_Task_Type_Declaration,
16525 N_Protected_Type_Declaration)
16527 if not Is_Limited_Record (Prev) then
16529 ("completion of nonlimited type cannot be limited", N);
16531 elsif No (Interface_List (N)) then
16533 ("completion of tagged private type must be tagged",
16538 -- Ada 2005 (AI-251): Private extension declaration of a task
16539 -- type or a protected type. This case arises when covering
16540 -- interface types.
16542 elsif Nkind_In (N, N_Task_Type_Declaration,
16543 N_Protected_Type_Declaration)
16547 elsif Nkind (N) /= N_Full_Type_Declaration
16548 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
16551 ("full view of private extension must be an extension", N);
16553 elsif not (Abstract_Present (Parent (Prev)))
16554 and then Abstract_Present (Type_Definition (N))
16557 ("full view of non-abstract extension cannot be abstract", N);
16560 if not In_Private_Part (Current_Scope) then
16562 ("declaration of full view must appear in private part", N);
16565 if Ada_Version >= Ada_2012 then
16566 Check_Duplicate_Aspects;
16569 Copy_And_Swap (Prev, Id);
16570 Set_Has_Private_Declaration (Prev);
16571 Set_Has_Private_Declaration (Id);
16573 -- AI12-0133: Indicate whether we have a partial view with
16574 -- unknown discriminants, in which case initialization of objects
16575 -- of the type do not receive an invariant check.
16577 Set_Partial_View_Has_Unknown_Discr
16578 (Prev, Has_Unknown_Discriminants (Id));
16580 -- Preserve aspect and iterator flags that may have been set on
16581 -- the partial view.
16583 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
16584 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
16586 -- If no error, propagate freeze_node from private to full view.
16587 -- It may have been generated for an early operational item.
16589 if Present (Freeze_Node (Id))
16590 and then Serious_Errors_Detected = 0
16591 and then No (Full_View (Id))
16593 Set_Freeze_Node (Prev, Freeze_Node (Id));
16594 Set_Freeze_Node (Id, Empty);
16595 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
16598 Set_Full_View (Id, Prev);
16602 -- Verify that full declaration conforms to partial one
16604 if Is_Incomplete_Or_Private_Type (Prev)
16605 and then Present (Discriminant_Specifications (Prev_Par))
16607 if Present (Discriminant_Specifications (N)) then
16608 if Ekind (Prev) = E_Incomplete_Type then
16609 Check_Discriminant_Conformance (N, Prev, Prev);
16611 Check_Discriminant_Conformance (N, Prev, Id);
16616 ("missing discriminants in full type declaration", N);
16618 -- To avoid cascaded errors on subsequent use, share the
16619 -- discriminants of the partial view.
16621 Set_Discriminant_Specifications (N,
16622 Discriminant_Specifications (Prev_Par));
16626 -- A prior untagged partial view can have an associated class-wide
16627 -- type due to use of the class attribute, and in this case the full
16628 -- type must also be tagged. This Ada 95 usage is deprecated in favor
16629 -- of incomplete tagged declarations, but we check for it.
16632 and then (Is_Tagged_Type (Prev)
16633 or else Present (Class_Wide_Type (Prev)))
16635 -- Ada 2012 (AI05-0162): A private type may be the completion of
16636 -- an incomplete type.
16638 if Ada_Version >= Ada_2012
16639 and then Is_Incomplete_Type (Prev)
16640 and then Nkind_In (N, N_Private_Type_Declaration,
16641 N_Private_Extension_Declaration)
16643 -- No need to check private extensions since they are tagged
16645 if Nkind (N) = N_Private_Type_Declaration
16646 and then not Tagged_Present (N)
16651 -- The full declaration is either a tagged type (including
16652 -- a synchronized type that implements interfaces) or a
16653 -- type extension, otherwise this is an error.
16655 elsif Nkind_In (N, N_Task_Type_Declaration,
16656 N_Protected_Type_Declaration)
16658 if No (Interface_List (N)) and then not Error_Posted (N) then
16662 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
16664 -- Indicate that the previous declaration (tagged incomplete
16665 -- or private declaration) requires the same on the full one.
16667 if not Tagged_Present (Type_Definition (N)) then
16669 Set_Is_Tagged_Type (Id);
16672 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
16673 if No (Record_Extension_Part (Type_Definition (N))) then
16675 ("full declaration of } must be a record extension",
16678 -- Set some attributes to produce a usable full view
16680 Set_Is_Tagged_Type (Id);
16689 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
16690 and then Present (Premature_Use (Parent (Prev)))
16692 Error_Msg_Sloc := Sloc (N);
16694 ("\full declaration #", Premature_Use (Parent (Prev)));
16699 end Find_Type_Name;
16701 -------------------------
16702 -- Find_Type_Of_Object --
16703 -------------------------
16705 function Find_Type_Of_Object
16706 (Obj_Def : Node_Id;
16707 Related_Nod : Node_Id) return Entity_Id
16709 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
16710 P : Node_Id := Parent (Obj_Def);
16715 -- If the parent is a component_definition node we climb to the
16716 -- component_declaration node
16718 if Nkind (P) = N_Component_Definition then
16722 -- Case of an anonymous array subtype
16724 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
16725 N_Unconstrained_Array_Definition)
16728 Array_Type_Declaration (T, Obj_Def);
16730 -- Create an explicit subtype whenever possible
16732 elsif Nkind (P) /= N_Component_Declaration
16733 and then Def_Kind = N_Subtype_Indication
16735 -- Base name of subtype on object name, which will be unique in
16736 -- the current scope.
16738 -- If this is a duplicate declaration, return base type, to avoid
16739 -- generating duplicate anonymous types.
16741 if Error_Posted (P) then
16742 Analyze (Subtype_Mark (Obj_Def));
16743 return Entity (Subtype_Mark (Obj_Def));
16748 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
16750 T := Make_Defining_Identifier (Sloc (P), Nam);
16752 Insert_Action (Obj_Def,
16753 Make_Subtype_Declaration (Sloc (P),
16754 Defining_Identifier => T,
16755 Subtype_Indication => Relocate_Node (Obj_Def)));
16757 -- This subtype may need freezing, and this will not be done
16758 -- automatically if the object declaration is not in declarative
16759 -- part. Since this is an object declaration, the type cannot always
16760 -- be frozen here. Deferred constants do not freeze their type
16761 -- (which often enough will be private).
16763 if Nkind (P) = N_Object_Declaration
16764 and then Constant_Present (P)
16765 and then No (Expression (P))
16769 -- Here we freeze the base type of object type to catch premature use
16770 -- of discriminated private type without a full view.
16773 Insert_Actions (Obj_Def, Freeze_Entity (Base_Type (T), P));
16776 -- Ada 2005 AI-406: the object definition in an object declaration
16777 -- can be an access definition.
16779 elsif Def_Kind = N_Access_Definition then
16780 T := Access_Definition (Related_Nod, Obj_Def);
16782 Set_Is_Local_Anonymous_Access
16784 V => (Ada_Version < Ada_2012)
16785 or else (Nkind (P) /= N_Object_Declaration)
16786 or else Is_Library_Level_Entity (Defining_Identifier (P)));
16788 -- Otherwise, the object definition is just a subtype_mark
16791 T := Process_Subtype (Obj_Def, Related_Nod);
16793 -- If expansion is disabled an object definition that is an aggregate
16794 -- will not get expanded and may lead to scoping problems in the back
16795 -- end, if the object is referenced in an inner scope. In that case
16796 -- create an itype reference for the object definition now. This
16797 -- may be redundant in some cases, but harmless.
16800 and then Nkind (Related_Nod) = N_Object_Declaration
16803 Build_Itype_Reference (T, Related_Nod);
16808 end Find_Type_Of_Object;
16810 --------------------------------
16811 -- Find_Type_Of_Subtype_Indic --
16812 --------------------------------
16814 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
16818 -- Case of subtype mark with a constraint
16820 if Nkind (S) = N_Subtype_Indication then
16821 Find_Type (Subtype_Mark (S));
16822 Typ := Entity (Subtype_Mark (S));
16825 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
16828 ("incorrect constraint for this kind of type", Constraint (S));
16829 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
16832 -- Otherwise we have a subtype mark without a constraint
16834 elsif Error_Posted (S) then
16835 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
16843 -- Check No_Wide_Characters restriction
16845 Check_Wide_Character_Restriction (Typ, S);
16848 end Find_Type_Of_Subtype_Indic;
16850 -------------------------------------
16851 -- Floating_Point_Type_Declaration --
16852 -------------------------------------
16854 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16855 Digs : constant Node_Id := Digits_Expression (Def);
16856 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
16858 Base_Typ : Entity_Id;
16859 Implicit_Base : Entity_Id;
16862 function Can_Derive_From (E : Entity_Id) return Boolean;
16863 -- Find if given digits value, and possibly a specified range, allows
16864 -- derivation from specified type
16866 function Find_Base_Type return Entity_Id;
16867 -- Find a predefined base type that Def can derive from, or generate
16868 -- an error and substitute Long_Long_Float if none exists.
16870 ---------------------
16871 -- Can_Derive_From --
16872 ---------------------
16874 function Can_Derive_From (E : Entity_Id) return Boolean is
16875 Spec : constant Entity_Id := Real_Range_Specification (Def);
16878 -- Check specified "digits" constraint
16880 if Digs_Val > Digits_Value (E) then
16884 -- Check for matching range, if specified
16886 if Present (Spec) then
16887 if Expr_Value_R (Type_Low_Bound (E)) >
16888 Expr_Value_R (Low_Bound (Spec))
16893 if Expr_Value_R (Type_High_Bound (E)) <
16894 Expr_Value_R (High_Bound (Spec))
16901 end Can_Derive_From;
16903 --------------------
16904 -- Find_Base_Type --
16905 --------------------
16907 function Find_Base_Type return Entity_Id is
16908 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
16911 -- Iterate over the predefined types in order, returning the first
16912 -- one that Def can derive from.
16914 while Present (Choice) loop
16915 if Can_Derive_From (Node (Choice)) then
16916 return Node (Choice);
16919 Next_Elmt (Choice);
16922 -- If we can't derive from any existing type, use Long_Long_Float
16923 -- and give appropriate message explaining the problem.
16925 if Digs_Val > Max_Digs_Val then
16926 -- It might be the case that there is a type with the requested
16927 -- range, just not the combination of digits and range.
16930 ("no predefined type has requested range and precision",
16931 Real_Range_Specification (Def));
16935 ("range too large for any predefined type",
16936 Real_Range_Specification (Def));
16939 return Standard_Long_Long_Float;
16940 end Find_Base_Type;
16942 -- Start of processing for Floating_Point_Type_Declaration
16945 Check_Restriction (No_Floating_Point, Def);
16947 -- Create an implicit base type
16950 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
16952 -- Analyze and verify digits value
16954 Analyze_And_Resolve (Digs, Any_Integer);
16955 Check_Digits_Expression (Digs);
16956 Digs_Val := Expr_Value (Digs);
16958 -- Process possible range spec and find correct type to derive from
16960 Process_Real_Range_Specification (Def);
16962 -- Check that requested number of digits is not too high.
16964 if Digs_Val > Max_Digs_Val then
16966 -- The check for Max_Base_Digits may be somewhat expensive, as it
16967 -- requires reading System, so only do it when necessary.
16970 Max_Base_Digits : constant Uint :=
16973 (Parent (RTE (RE_Max_Base_Digits))));
16976 if Digs_Val > Max_Base_Digits then
16977 Error_Msg_Uint_1 := Max_Base_Digits;
16978 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
16980 elsif No (Real_Range_Specification (Def)) then
16981 Error_Msg_Uint_1 := Max_Digs_Val;
16982 Error_Msg_N ("types with more than ^ digits need range spec "
16983 & "(RM 3.5.7(6))", Digs);
16988 -- Find a suitable type to derive from or complain and use a substitute
16990 Base_Typ := Find_Base_Type;
16992 -- If there are bounds given in the declaration use them as the bounds
16993 -- of the type, otherwise use the bounds of the predefined base type
16994 -- that was chosen based on the Digits value.
16996 if Present (Real_Range_Specification (Def)) then
16997 Set_Scalar_Range (T, Real_Range_Specification (Def));
16998 Set_Is_Constrained (T);
17000 -- The bounds of this range must be converted to machine numbers
17001 -- in accordance with RM 4.9(38).
17003 Bound := Type_Low_Bound (T);
17005 if Nkind (Bound) = N_Real_Literal then
17007 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17008 Set_Is_Machine_Number (Bound);
17011 Bound := Type_High_Bound (T);
17013 if Nkind (Bound) = N_Real_Literal then
17015 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
17016 Set_Is_Machine_Number (Bound);
17020 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
17023 -- Complete definition of implicit base and declared first subtype. The
17024 -- inheritance of the rep item chain ensures that SPARK-related pragmas
17025 -- are not clobbered when the floating point type acts as a full view of
17028 Set_Etype (Implicit_Base, Base_Typ);
17029 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
17030 Set_Size_Info (Implicit_Base, Base_Typ);
17031 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
17032 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
17033 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
17034 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
17036 Set_Ekind (T, E_Floating_Point_Subtype);
17037 Set_Etype (T, Implicit_Base);
17038 Set_Size_Info (T, Implicit_Base);
17039 Set_RM_Size (T, RM_Size (Implicit_Base));
17040 Inherit_Rep_Item_Chain (T, Implicit_Base);
17041 Set_Digits_Value (T, Digs_Val);
17042 end Floating_Point_Type_Declaration;
17044 ----------------------------
17045 -- Get_Discriminant_Value --
17046 ----------------------------
17048 -- This is the situation:
17050 -- There is a non-derived type
17052 -- type T0 (Dx, Dy, Dz...)
17054 -- There are zero or more levels of derivation, with each derivation
17055 -- either purely inheriting the discriminants, or defining its own.
17057 -- type Ti is new Ti-1
17059 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
17061 -- subtype Ti is ...
17063 -- The subtype issue is avoided by the use of Original_Record_Component,
17064 -- and the fact that derived subtypes also derive the constraints.
17066 -- This chain leads back from
17068 -- Typ_For_Constraint
17070 -- Typ_For_Constraint has discriminants, and the value for each
17071 -- discriminant is given by its corresponding Elmt of Constraints.
17073 -- Discriminant is some discriminant in this hierarchy
17075 -- We need to return its value
17077 -- We do this by recursively searching each level, and looking for
17078 -- Discriminant. Once we get to the bottom, we start backing up
17079 -- returning the value for it which may in turn be a discriminant
17080 -- further up, so on the backup we continue the substitution.
17082 function Get_Discriminant_Value
17083 (Discriminant : Entity_Id;
17084 Typ_For_Constraint : Entity_Id;
17085 Constraint : Elist_Id) return Node_Id
17087 function Root_Corresponding_Discriminant
17088 (Discr : Entity_Id) return Entity_Id;
17089 -- Given a discriminant, traverse the chain of inherited discriminants
17090 -- and return the topmost discriminant.
17092 function Search_Derivation_Levels
17094 Discrim_Values : Elist_Id;
17095 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
17096 -- This is the routine that performs the recursive search of levels
17097 -- as described above.
17099 -------------------------------------
17100 -- Root_Corresponding_Discriminant --
17101 -------------------------------------
17103 function Root_Corresponding_Discriminant
17104 (Discr : Entity_Id) return Entity_Id
17110 while Present (Corresponding_Discriminant (D)) loop
17111 D := Corresponding_Discriminant (D);
17115 end Root_Corresponding_Discriminant;
17117 ------------------------------
17118 -- Search_Derivation_Levels --
17119 ------------------------------
17121 function Search_Derivation_Levels
17123 Discrim_Values : Elist_Id;
17124 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
17128 Result : Node_Or_Entity_Id;
17129 Result_Entity : Node_Id;
17132 -- If inappropriate type, return Error, this happens only in
17133 -- cascaded error situations, and we want to avoid a blow up.
17135 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
17139 -- Look deeper if possible. Use Stored_Constraints only for
17140 -- untagged types. For tagged types use the given constraint.
17141 -- This asymmetry needs explanation???
17143 if not Stored_Discrim_Values
17144 and then Present (Stored_Constraint (Ti))
17145 and then not Is_Tagged_Type (Ti)
17148 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
17151 Td : constant Entity_Id := Etype (Ti);
17155 Result := Discriminant;
17158 if Present (Stored_Constraint (Ti)) then
17160 Search_Derivation_Levels
17161 (Td, Stored_Constraint (Ti), True);
17164 Search_Derivation_Levels
17165 (Td, Discrim_Values, Stored_Discrim_Values);
17171 -- Extra underlying places to search, if not found above. For
17172 -- concurrent types, the relevant discriminant appears in the
17173 -- corresponding record. For a type derived from a private type
17174 -- without discriminant, the full view inherits the discriminants
17175 -- of the full view of the parent.
17177 if Result = Discriminant then
17178 if Is_Concurrent_Type (Ti)
17179 and then Present (Corresponding_Record_Type (Ti))
17182 Search_Derivation_Levels (
17183 Corresponding_Record_Type (Ti),
17185 Stored_Discrim_Values);
17187 elsif Is_Private_Type (Ti)
17188 and then not Has_Discriminants (Ti)
17189 and then Present (Full_View (Ti))
17190 and then Etype (Full_View (Ti)) /= Ti
17193 Search_Derivation_Levels (
17196 Stored_Discrim_Values);
17200 -- If Result is not a (reference to a) discriminant, return it,
17201 -- otherwise set Result_Entity to the discriminant.
17203 if Nkind (Result) = N_Defining_Identifier then
17204 pragma Assert (Result = Discriminant);
17205 Result_Entity := Result;
17208 if not Denotes_Discriminant (Result) then
17212 Result_Entity := Entity (Result);
17215 -- See if this level of derivation actually has discriminants because
17216 -- tagged derivations can add them, hence the lower levels need not
17219 if not Has_Discriminants (Ti) then
17223 -- Scan Ti's discriminants for Result_Entity, and return its
17224 -- corresponding value, if any.
17226 Result_Entity := Original_Record_Component (Result_Entity);
17228 Assoc := First_Elmt (Discrim_Values);
17230 if Stored_Discrim_Values then
17231 Disc := First_Stored_Discriminant (Ti);
17233 Disc := First_Discriminant (Ti);
17236 while Present (Disc) loop
17237 pragma Assert (Present (Assoc));
17239 if Original_Record_Component (Disc) = Result_Entity then
17240 return Node (Assoc);
17245 if Stored_Discrim_Values then
17246 Next_Stored_Discriminant (Disc);
17248 Next_Discriminant (Disc);
17252 -- Could not find it
17255 end Search_Derivation_Levels;
17259 Result : Node_Or_Entity_Id;
17261 -- Start of processing for Get_Discriminant_Value
17264 -- ??? This routine is a gigantic mess and will be deleted. For the
17265 -- time being just test for the trivial case before calling recurse.
17267 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
17273 D := First_Discriminant (Typ_For_Constraint);
17274 E := First_Elmt (Constraint);
17275 while Present (D) loop
17276 if Chars (D) = Chars (Discriminant) then
17280 Next_Discriminant (D);
17286 Result := Search_Derivation_Levels
17287 (Typ_For_Constraint, Constraint, False);
17289 -- ??? hack to disappear when this routine is gone
17291 if Nkind (Result) = N_Defining_Identifier then
17297 D := First_Discriminant (Typ_For_Constraint);
17298 E := First_Elmt (Constraint);
17299 while Present (D) loop
17300 if Root_Corresponding_Discriminant (D) = Discriminant then
17304 Next_Discriminant (D);
17310 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
17312 end Get_Discriminant_Value;
17314 --------------------------
17315 -- Has_Range_Constraint --
17316 --------------------------
17318 function Has_Range_Constraint (N : Node_Id) return Boolean is
17319 C : constant Node_Id := Constraint (N);
17322 if Nkind (C) = N_Range_Constraint then
17325 elsif Nkind (C) = N_Digits_Constraint then
17327 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
17328 or else Present (Range_Constraint (C));
17330 elsif Nkind (C) = N_Delta_Constraint then
17331 return Present (Range_Constraint (C));
17336 end Has_Range_Constraint;
17338 ------------------------
17339 -- Inherit_Components --
17340 ------------------------
17342 function Inherit_Components
17344 Parent_Base : Entity_Id;
17345 Derived_Base : Entity_Id;
17346 Is_Tagged : Boolean;
17347 Inherit_Discr : Boolean;
17348 Discs : Elist_Id) return Elist_Id
17350 Assoc_List : constant Elist_Id := New_Elmt_List;
17352 procedure Inherit_Component
17353 (Old_C : Entity_Id;
17354 Plain_Discrim : Boolean := False;
17355 Stored_Discrim : Boolean := False);
17356 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
17357 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
17358 -- True, Old_C is a stored discriminant. If they are both false then
17359 -- Old_C is a regular component.
17361 -----------------------
17362 -- Inherit_Component --
17363 -----------------------
17365 procedure Inherit_Component
17366 (Old_C : Entity_Id;
17367 Plain_Discrim : Boolean := False;
17368 Stored_Discrim : Boolean := False)
17370 procedure Set_Anonymous_Type (Id : Entity_Id);
17371 -- Id denotes the entity of an access discriminant or anonymous
17372 -- access component. Set the type of Id to either the same type of
17373 -- Old_C or create a new one depending on whether the parent and
17374 -- the child types are in the same scope.
17376 ------------------------
17377 -- Set_Anonymous_Type --
17378 ------------------------
17380 procedure Set_Anonymous_Type (Id : Entity_Id) is
17381 Old_Typ : constant Entity_Id := Etype (Old_C);
17384 if Scope (Parent_Base) = Scope (Derived_Base) then
17385 Set_Etype (Id, Old_Typ);
17387 -- The parent and the derived type are in two different scopes.
17388 -- Reuse the type of the original discriminant / component by
17389 -- copying it in order to preserve all attributes.
17393 Typ : constant Entity_Id := New_Copy (Old_Typ);
17396 Set_Etype (Id, Typ);
17398 -- Since we do not generate component declarations for
17399 -- inherited components, associate the itype with the
17402 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
17403 Set_Scope (Typ, Derived_Base);
17406 end Set_Anonymous_Type;
17408 -- Local variables and constants
17410 New_C : constant Entity_Id := New_Copy (Old_C);
17412 Corr_Discrim : Entity_Id;
17413 Discrim : Entity_Id;
17415 -- Start of processing for Inherit_Component
17418 pragma Assert (not Is_Tagged or not Stored_Discrim);
17420 Set_Parent (New_C, Parent (Old_C));
17422 -- Regular discriminants and components must be inserted in the scope
17423 -- of the Derived_Base. Do it here.
17425 if not Stored_Discrim then
17426 Enter_Name (New_C);
17429 -- For tagged types the Original_Record_Component must point to
17430 -- whatever this field was pointing to in the parent type. This has
17431 -- already been achieved by the call to New_Copy above.
17433 if not Is_Tagged then
17434 Set_Original_Record_Component (New_C, New_C);
17437 -- Set the proper type of an access discriminant
17439 if Ekind (New_C) = E_Discriminant
17440 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
17442 Set_Anonymous_Type (New_C);
17445 -- If we have inherited a component then see if its Etype contains
17446 -- references to Parent_Base discriminants. In this case, replace
17447 -- these references with the constraints given in Discs. We do not
17448 -- do this for the partial view of private types because this is
17449 -- not needed (only the components of the full view will be used
17450 -- for code generation) and cause problem. We also avoid this
17451 -- transformation in some error situations.
17453 if Ekind (New_C) = E_Component then
17455 -- Set the proper type of an anonymous access component
17457 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
17458 Set_Anonymous_Type (New_C);
17460 elsif (Is_Private_Type (Derived_Base)
17461 and then not Is_Generic_Type (Derived_Base))
17462 or else (Is_Empty_Elmt_List (Discs)
17463 and then not Expander_Active)
17465 Set_Etype (New_C, Etype (Old_C));
17468 -- The current component introduces a circularity of the
17471 -- limited with Pack_2;
17472 -- package Pack_1 is
17473 -- type T_1 is tagged record
17474 -- Comp : access Pack_2.T_2;
17480 -- package Pack_2 is
17481 -- type T_2 is new Pack_1.T_1 with ...;
17486 Constrain_Component_Type
17487 (Old_C, Derived_Base, N, Parent_Base, Discs));
17491 -- In derived tagged types it is illegal to reference a non
17492 -- discriminant component in the parent type. To catch this, mark
17493 -- these components with an Ekind of E_Void. This will be reset in
17494 -- Record_Type_Definition after processing the record extension of
17495 -- the derived type.
17497 -- If the declaration is a private extension, there is no further
17498 -- record extension to process, and the components retain their
17499 -- current kind, because they are visible at this point.
17501 if Is_Tagged and then Ekind (New_C) = E_Component
17502 and then Nkind (N) /= N_Private_Extension_Declaration
17504 Set_Ekind (New_C, E_Void);
17507 if Plain_Discrim then
17508 Set_Corresponding_Discriminant (New_C, Old_C);
17509 Build_Discriminal (New_C);
17511 -- If we are explicitly inheriting a stored discriminant it will be
17512 -- completely hidden.
17514 elsif Stored_Discrim then
17515 Set_Corresponding_Discriminant (New_C, Empty);
17516 Set_Discriminal (New_C, Empty);
17517 Set_Is_Completely_Hidden (New_C);
17519 -- Set the Original_Record_Component of each discriminant in the
17520 -- derived base to point to the corresponding stored that we just
17523 Discrim := First_Discriminant (Derived_Base);
17524 while Present (Discrim) loop
17525 Corr_Discrim := Corresponding_Discriminant (Discrim);
17527 -- Corr_Discrim could be missing in an error situation
17529 if Present (Corr_Discrim)
17530 and then Original_Record_Component (Corr_Discrim) = Old_C
17532 Set_Original_Record_Component (Discrim, New_C);
17535 Next_Discriminant (Discrim);
17538 Append_Entity (New_C, Derived_Base);
17541 if not Is_Tagged then
17542 Append_Elmt (Old_C, Assoc_List);
17543 Append_Elmt (New_C, Assoc_List);
17545 end Inherit_Component;
17547 -- Variables local to Inherit_Component
17549 Loc : constant Source_Ptr := Sloc (N);
17551 Parent_Discrim : Entity_Id;
17552 Stored_Discrim : Entity_Id;
17554 Component : Entity_Id;
17556 -- Start of processing for Inherit_Components
17559 if not Is_Tagged then
17560 Append_Elmt (Parent_Base, Assoc_List);
17561 Append_Elmt (Derived_Base, Assoc_List);
17564 -- Inherit parent discriminants if needed
17566 if Inherit_Discr then
17567 Parent_Discrim := First_Discriminant (Parent_Base);
17568 while Present (Parent_Discrim) loop
17569 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
17570 Next_Discriminant (Parent_Discrim);
17574 -- Create explicit stored discrims for untagged types when necessary
17576 if not Has_Unknown_Discriminants (Derived_Base)
17577 and then Has_Discriminants (Parent_Base)
17578 and then not Is_Tagged
17581 or else First_Discriminant (Parent_Base) /=
17582 First_Stored_Discriminant (Parent_Base))
17584 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
17585 while Present (Stored_Discrim) loop
17586 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
17587 Next_Stored_Discriminant (Stored_Discrim);
17591 -- See if we can apply the second transformation for derived types, as
17592 -- explained in point 6. in the comments above Build_Derived_Record_Type
17593 -- This is achieved by appending Derived_Base discriminants into Discs,
17594 -- which has the side effect of returning a non empty Discs list to the
17595 -- caller of Inherit_Components, which is what we want. This must be
17596 -- done for private derived types if there are explicit stored
17597 -- discriminants, to ensure that we can retrieve the values of the
17598 -- constraints provided in the ancestors.
17601 and then Is_Empty_Elmt_List (Discs)
17602 and then Present (First_Discriminant (Derived_Base))
17604 (not Is_Private_Type (Derived_Base)
17605 or else Is_Completely_Hidden
17606 (First_Stored_Discriminant (Derived_Base))
17607 or else Is_Generic_Type (Derived_Base))
17609 D := First_Discriminant (Derived_Base);
17610 while Present (D) loop
17611 Append_Elmt (New_Occurrence_Of (D, Loc), Discs);
17612 Next_Discriminant (D);
17616 -- Finally, inherit non-discriminant components unless they are not
17617 -- visible because defined or inherited from the full view of the
17618 -- parent. Don't inherit the _parent field of the parent type.
17620 Component := First_Entity (Parent_Base);
17621 while Present (Component) loop
17623 -- Ada 2005 (AI-251): Do not inherit components associated with
17624 -- secondary tags of the parent.
17626 if Ekind (Component) = E_Component
17627 and then Present (Related_Type (Component))
17631 elsif Ekind (Component) /= E_Component
17632 or else Chars (Component) = Name_uParent
17636 -- If the derived type is within the parent type's declarative
17637 -- region, then the components can still be inherited even though
17638 -- they aren't visible at this point. This can occur for cases
17639 -- such as within public child units where the components must
17640 -- become visible upon entering the child unit's private part.
17642 elsif not Is_Visible_Component (Component)
17643 and then not In_Open_Scopes (Scope (Parent_Base))
17647 elsif Ekind_In (Derived_Base, E_Private_Type,
17648 E_Limited_Private_Type)
17653 Inherit_Component (Component);
17656 Next_Entity (Component);
17659 -- For tagged derived types, inherited discriminants cannot be used in
17660 -- component declarations of the record extension part. To achieve this
17661 -- we mark the inherited discriminants as not visible.
17663 if Is_Tagged and then Inherit_Discr then
17664 D := First_Discriminant (Derived_Base);
17665 while Present (D) loop
17666 Set_Is_Immediately_Visible (D, False);
17667 Next_Discriminant (D);
17672 end Inherit_Components;
17674 -----------------------------
17675 -- Inherit_Predicate_Flags --
17676 -----------------------------
17678 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id) is
17680 Set_Has_Predicates (Subt, Has_Predicates (Par));
17681 Set_Has_Static_Predicate_Aspect
17682 (Subt, Has_Static_Predicate_Aspect (Par));
17683 Set_Has_Dynamic_Predicate_Aspect
17684 (Subt, Has_Dynamic_Predicate_Aspect (Par));
17685 end Inherit_Predicate_Flags;
17687 ----------------------
17688 -- Is_EVF_Procedure --
17689 ----------------------
17691 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean is
17692 Formal : Entity_Id;
17695 -- Examine the formals of an Extensions_Visible False procedure looking
17696 -- for a controlling OUT parameter.
17698 if Ekind (Subp) = E_Procedure
17699 and then Extensions_Visible_Status (Subp) = Extensions_Visible_False
17701 Formal := First_Formal (Subp);
17702 while Present (Formal) loop
17703 if Ekind (Formal) = E_Out_Parameter
17704 and then Is_Controlling_Formal (Formal)
17709 Next_Formal (Formal);
17714 end Is_EVF_Procedure;
17716 -----------------------
17717 -- Is_Null_Extension --
17718 -----------------------
17720 function Is_Null_Extension (T : Entity_Id) return Boolean is
17721 Type_Decl : constant Node_Id := Parent (Base_Type (T));
17722 Comp_List : Node_Id;
17726 if Nkind (Type_Decl) /= N_Full_Type_Declaration
17727 or else not Is_Tagged_Type (T)
17728 or else Nkind (Type_Definition (Type_Decl)) /=
17729 N_Derived_Type_Definition
17730 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
17736 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
17738 if Present (Discriminant_Specifications (Type_Decl)) then
17741 elsif Present (Comp_List)
17742 and then Is_Non_Empty_List (Component_Items (Comp_List))
17744 Comp := First (Component_Items (Comp_List));
17746 -- Only user-defined components are relevant. The component list
17747 -- may also contain a parent component and internal components
17748 -- corresponding to secondary tags, but these do not determine
17749 -- whether this is a null extension.
17751 while Present (Comp) loop
17752 if Comes_From_Source (Comp) then
17764 end Is_Null_Extension;
17766 ------------------------------
17767 -- Is_Valid_Constraint_Kind --
17768 ------------------------------
17770 function Is_Valid_Constraint_Kind
17771 (T_Kind : Type_Kind;
17772 Constraint_Kind : Node_Kind) return Boolean
17776 when Enumeration_Kind |
17778 return Constraint_Kind = N_Range_Constraint;
17780 when Decimal_Fixed_Point_Kind =>
17781 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17782 N_Range_Constraint);
17784 when Ordinary_Fixed_Point_Kind =>
17785 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
17786 N_Range_Constraint);
17789 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17790 N_Range_Constraint);
17797 E_Incomplete_Type |
17800 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
17803 return True; -- Error will be detected later
17805 end Is_Valid_Constraint_Kind;
17807 --------------------------
17808 -- Is_Visible_Component --
17809 --------------------------
17811 function Is_Visible_Component
17813 N : Node_Id := Empty) return Boolean
17815 Original_Comp : Entity_Id := Empty;
17816 Original_Scope : Entity_Id;
17817 Type_Scope : Entity_Id;
17819 function Is_Local_Type (Typ : Entity_Id) return Boolean;
17820 -- Check whether parent type of inherited component is declared locally,
17821 -- possibly within a nested package or instance. The current scope is
17822 -- the derived record itself.
17824 -------------------
17825 -- Is_Local_Type --
17826 -------------------
17828 function Is_Local_Type (Typ : Entity_Id) return Boolean is
17832 Scop := Scope (Typ);
17833 while Present (Scop)
17834 and then Scop /= Standard_Standard
17836 if Scop = Scope (Current_Scope) then
17840 Scop := Scope (Scop);
17846 -- Start of processing for Is_Visible_Component
17849 if Ekind_In (C, E_Component, E_Discriminant) then
17850 Original_Comp := Original_Record_Component (C);
17853 if No (Original_Comp) then
17855 -- Premature usage, or previous error
17860 Original_Scope := Scope (Original_Comp);
17861 Type_Scope := Scope (Base_Type (Scope (C)));
17864 -- This test only concerns tagged types
17866 if not Is_Tagged_Type (Original_Scope) then
17869 -- If it is _Parent or _Tag, there is no visibility issue
17871 elsif not Comes_From_Source (Original_Comp) then
17874 -- Discriminants are visible unless the (private) type has unknown
17875 -- discriminants. If the discriminant reference is inserted for a
17876 -- discriminant check on a full view it is also visible.
17878 elsif Ekind (Original_Comp) = E_Discriminant
17880 (not Has_Unknown_Discriminants (Original_Scope)
17881 or else (Present (N)
17882 and then Nkind (N) = N_Selected_Component
17883 and then Nkind (Prefix (N)) = N_Type_Conversion
17884 and then not Comes_From_Source (Prefix (N))))
17888 -- In the body of an instantiation, no need to check for the visibility
17891 elsif In_Instance_Body then
17894 -- If the component has been declared in an ancestor which is currently
17895 -- a private type, then it is not visible. The same applies if the
17896 -- component's containing type is not in an open scope and the original
17897 -- component's enclosing type is a visible full view of a private type
17898 -- (which can occur in cases where an attempt is being made to reference
17899 -- a component in a sibling package that is inherited from a visible
17900 -- component of a type in an ancestor package; the component in the
17901 -- sibling package should not be visible even though the component it
17902 -- inherited from is visible). This does not apply however in the case
17903 -- where the scope of the type is a private child unit, or when the
17904 -- parent comes from a local package in which the ancestor is currently
17905 -- visible. The latter suppression of visibility is needed for cases
17906 -- that are tested in B730006.
17908 elsif Is_Private_Type (Original_Scope)
17910 (not Is_Private_Descendant (Type_Scope)
17911 and then not In_Open_Scopes (Type_Scope)
17912 and then Has_Private_Declaration (Original_Scope))
17914 -- If the type derives from an entity in a formal package, there
17915 -- are no additional visible components.
17917 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
17918 N_Formal_Package_Declaration
17922 -- if we are not in the private part of the current package, there
17923 -- are no additional visible components.
17925 elsif Ekind (Scope (Current_Scope)) = E_Package
17926 and then not In_Private_Part (Scope (Current_Scope))
17931 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
17932 and then In_Open_Scopes (Scope (Original_Scope))
17933 and then Is_Local_Type (Type_Scope);
17936 -- There is another weird way in which a component may be invisible when
17937 -- the private and the full view are not derived from the same ancestor.
17938 -- Here is an example :
17940 -- type A1 is tagged record F1 : integer; end record;
17941 -- type A2 is new A1 with record F2 : integer; end record;
17942 -- type T is new A1 with private;
17944 -- type T is new A2 with null record;
17946 -- In this case, the full view of T inherits F1 and F2 but the private
17947 -- view inherits only F1
17951 Ancestor : Entity_Id := Scope (C);
17955 if Ancestor = Original_Scope then
17957 elsif Ancestor = Etype (Ancestor) then
17961 Ancestor := Etype (Ancestor);
17965 end Is_Visible_Component;
17967 --------------------------
17968 -- Make_Class_Wide_Type --
17969 --------------------------
17971 procedure Make_Class_Wide_Type (T : Entity_Id) is
17972 CW_Type : Entity_Id;
17974 Next_E : Entity_Id;
17977 if Present (Class_Wide_Type (T)) then
17979 -- The class-wide type is a partially decorated entity created for a
17980 -- unanalyzed tagged type referenced through a limited with clause.
17981 -- When the tagged type is analyzed, its class-wide type needs to be
17982 -- redecorated. Note that we reuse the entity created by Decorate_
17983 -- Tagged_Type in order to preserve all links.
17985 if Materialize_Entity (Class_Wide_Type (T)) then
17986 CW_Type := Class_Wide_Type (T);
17987 Set_Materialize_Entity (CW_Type, False);
17989 -- The class wide type can have been defined by the partial view, in
17990 -- which case everything is already done.
17996 -- Default case, we need to create a new class-wide type
18000 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
18003 -- Inherit root type characteristics
18005 CW_Name := Chars (CW_Type);
18006 Next_E := Next_Entity (CW_Type);
18007 Copy_Node (T, CW_Type);
18008 Set_Comes_From_Source (CW_Type, False);
18009 Set_Chars (CW_Type, CW_Name);
18010 Set_Parent (CW_Type, Parent (T));
18011 Set_Next_Entity (CW_Type, Next_E);
18013 -- Ensure we have a new freeze node for the class-wide type. The partial
18014 -- view may have freeze action of its own, requiring a proper freeze
18015 -- node, and the same freeze node cannot be shared between the two
18018 Set_Has_Delayed_Freeze (CW_Type);
18019 Set_Freeze_Node (CW_Type, Empty);
18021 -- Customize the class-wide type: It has no prim. op., it cannot be
18022 -- abstract and its Etype points back to the specific root type.
18024 Set_Ekind (CW_Type, E_Class_Wide_Type);
18025 Set_Is_Tagged_Type (CW_Type, True);
18026 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
18027 Set_Is_Abstract_Type (CW_Type, False);
18028 Set_Is_Constrained (CW_Type, False);
18029 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
18030 Set_Default_SSO (CW_Type);
18032 if Ekind (T) = E_Class_Wide_Subtype then
18033 Set_Etype (CW_Type, Etype (Base_Type (T)));
18035 Set_Etype (CW_Type, T);
18038 Set_No_Tagged_Streams_Pragma (CW_Type, No_Tagged_Streams);
18040 -- If this is the class_wide type of a constrained subtype, it does
18041 -- not have discriminants.
18043 Set_Has_Discriminants (CW_Type,
18044 Has_Discriminants (T) and then not Is_Constrained (T));
18046 Set_Has_Unknown_Discriminants (CW_Type, True);
18047 Set_Class_Wide_Type (T, CW_Type);
18048 Set_Equivalent_Type (CW_Type, Empty);
18050 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
18052 Set_Class_Wide_Type (CW_Type, CW_Type);
18053 end Make_Class_Wide_Type;
18059 procedure Make_Index
18061 Related_Nod : Node_Id;
18062 Related_Id : Entity_Id := Empty;
18063 Suffix_Index : Nat := 1;
18064 In_Iter_Schm : Boolean := False)
18068 Def_Id : Entity_Id := Empty;
18069 Found : Boolean := False;
18072 -- For a discrete range used in a constrained array definition and
18073 -- defined by a range, an implicit conversion to the predefined type
18074 -- INTEGER is assumed if each bound is either a numeric literal, a named
18075 -- number, or an attribute, and the type of both bounds (prior to the
18076 -- implicit conversion) is the type universal_integer. Otherwise, both
18077 -- bounds must be of the same discrete type, other than universal
18078 -- integer; this type must be determinable independently of the
18079 -- context, but using the fact that the type must be discrete and that
18080 -- both bounds must have the same type.
18082 -- Character literals also have a universal type in the absence of
18083 -- of additional context, and are resolved to Standard_Character.
18085 if Nkind (N) = N_Range then
18087 -- The index is given by a range constraint. The bounds are known
18088 -- to be of a consistent type.
18090 if not Is_Overloaded (N) then
18093 -- For universal bounds, choose the specific predefined type
18095 if T = Universal_Integer then
18096 T := Standard_Integer;
18098 elsif T = Any_Character then
18099 Ambiguous_Character (Low_Bound (N));
18101 T := Standard_Character;
18104 -- The node may be overloaded because some user-defined operators
18105 -- are available, but if a universal interpretation exists it is
18106 -- also the selected one.
18108 elsif Universal_Interpretation (N) = Universal_Integer then
18109 T := Standard_Integer;
18115 Ind : Interp_Index;
18119 Get_First_Interp (N, Ind, It);
18120 while Present (It.Typ) loop
18121 if Is_Discrete_Type (It.Typ) then
18124 and then not Covers (It.Typ, T)
18125 and then not Covers (T, It.Typ)
18127 Error_Msg_N ("ambiguous bounds in discrete range", N);
18135 Get_Next_Interp (Ind, It);
18138 if T = Any_Type then
18139 Error_Msg_N ("discrete type required for range", N);
18140 Set_Etype (N, Any_Type);
18143 elsif T = Universal_Integer then
18144 T := Standard_Integer;
18149 if not Is_Discrete_Type (T) then
18150 Error_Msg_N ("discrete type required for range", N);
18151 Set_Etype (N, Any_Type);
18155 if Nkind (Low_Bound (N)) = N_Attribute_Reference
18156 and then Attribute_Name (Low_Bound (N)) = Name_First
18157 and then Is_Entity_Name (Prefix (Low_Bound (N)))
18158 and then Is_Type (Entity (Prefix (Low_Bound (N))))
18159 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (N))))
18161 -- The type of the index will be the type of the prefix, as long
18162 -- as the upper bound is 'Last of the same type.
18164 Def_Id := Entity (Prefix (Low_Bound (N)));
18166 if Nkind (High_Bound (N)) /= N_Attribute_Reference
18167 or else Attribute_Name (High_Bound (N)) /= Name_Last
18168 or else not Is_Entity_Name (Prefix (High_Bound (N)))
18169 or else Entity (Prefix (High_Bound (N))) /= Def_Id
18176 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
18178 elsif Nkind (N) = N_Subtype_Indication then
18180 -- The index is given by a subtype with a range constraint
18182 T := Base_Type (Entity (Subtype_Mark (N)));
18184 if not Is_Discrete_Type (T) then
18185 Error_Msg_N ("discrete type required for range", N);
18186 Set_Etype (N, Any_Type);
18190 R := Range_Expression (Constraint (N));
18193 Process_Range_Expr_In_Decl
18194 (R, Entity (Subtype_Mark (N)), In_Iter_Schm => In_Iter_Schm);
18196 elsif Nkind (N) = N_Attribute_Reference then
18198 -- Catch beginner's error (use of attribute other than 'Range)
18200 if Attribute_Name (N) /= Name_Range then
18201 Error_Msg_N ("expect attribute ''Range", N);
18202 Set_Etype (N, Any_Type);
18206 -- If the node denotes the range of a type mark, that is also the
18207 -- resulting type, and we do not need to create an Itype for it.
18209 if Is_Entity_Name (Prefix (N))
18210 and then Comes_From_Source (N)
18211 and then Is_Type (Entity (Prefix (N)))
18212 and then Is_Discrete_Type (Entity (Prefix (N)))
18214 Def_Id := Entity (Prefix (N));
18217 Analyze_And_Resolve (N);
18221 -- If none of the above, must be a subtype. We convert this to a
18222 -- range attribute reference because in the case of declared first
18223 -- named subtypes, the types in the range reference can be different
18224 -- from the type of the entity. A range attribute normalizes the
18225 -- reference and obtains the correct types for the bounds.
18227 -- This transformation is in the nature of an expansion, is only
18228 -- done if expansion is active. In particular, it is not done on
18229 -- formal generic types, because we need to retain the name of the
18230 -- original index for instantiation purposes.
18233 if not Is_Entity_Name (N) or else not Is_Type (Entity (N)) then
18234 Error_Msg_N ("invalid subtype mark in discrete range ", N);
18235 Set_Etype (N, Any_Integer);
18239 -- The type mark may be that of an incomplete type. It is only
18240 -- now that we can get the full view, previous analysis does
18241 -- not look specifically for a type mark.
18243 Set_Entity (N, Get_Full_View (Entity (N)));
18244 Set_Etype (N, Entity (N));
18245 Def_Id := Entity (N);
18247 if not Is_Discrete_Type (Def_Id) then
18248 Error_Msg_N ("discrete type required for index", N);
18249 Set_Etype (N, Any_Type);
18254 if Expander_Active then
18256 Make_Attribute_Reference (Sloc (N),
18257 Attribute_Name => Name_Range,
18258 Prefix => Relocate_Node (N)));
18260 -- The original was a subtype mark that does not freeze. This
18261 -- means that the rewritten version must not freeze either.
18263 Set_Must_Not_Freeze (N);
18264 Set_Must_Not_Freeze (Prefix (N));
18265 Analyze_And_Resolve (N);
18269 -- If expander is inactive, type is legal, nothing else to construct
18276 if not Is_Discrete_Type (T) then
18277 Error_Msg_N ("discrete type required for range", N);
18278 Set_Etype (N, Any_Type);
18281 elsif T = Any_Type then
18282 Set_Etype (N, Any_Type);
18286 -- We will now create the appropriate Itype to describe the range, but
18287 -- first a check. If we originally had a subtype, then we just label
18288 -- the range with this subtype. Not only is there no need to construct
18289 -- a new subtype, but it is wrong to do so for two reasons:
18291 -- 1. A legality concern, if we have a subtype, it must not freeze,
18292 -- and the Itype would cause freezing incorrectly
18294 -- 2. An efficiency concern, if we created an Itype, it would not be
18295 -- recognized as the same type for the purposes of eliminating
18296 -- checks in some circumstances.
18298 -- We signal this case by setting the subtype entity in Def_Id
18300 if No (Def_Id) then
18302 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
18303 Set_Etype (Def_Id, Base_Type (T));
18305 if Is_Signed_Integer_Type (T) then
18306 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
18308 elsif Is_Modular_Integer_Type (T) then
18309 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
18312 Set_Ekind (Def_Id, E_Enumeration_Subtype);
18313 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
18314 Set_First_Literal (Def_Id, First_Literal (T));
18317 Set_Size_Info (Def_Id, (T));
18318 Set_RM_Size (Def_Id, RM_Size (T));
18319 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
18321 Set_Scalar_Range (Def_Id, R);
18322 Conditional_Delay (Def_Id, T);
18324 if Nkind (N) = N_Subtype_Indication then
18325 Inherit_Predicate_Flags (Def_Id, Entity (Subtype_Mark (N)));
18328 -- In the subtype indication case, if the immediate parent of the
18329 -- new subtype is non-static, then the subtype we create is non-
18330 -- static, even if its bounds are static.
18332 if Nkind (N) = N_Subtype_Indication
18333 and then not Is_OK_Static_Subtype (Entity (Subtype_Mark (N)))
18335 Set_Is_Non_Static_Subtype (Def_Id);
18339 -- Final step is to label the index with this constructed type
18341 Set_Etype (N, Def_Id);
18344 ------------------------------
18345 -- Modular_Type_Declaration --
18346 ------------------------------
18348 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
18349 Mod_Expr : constant Node_Id := Expression (Def);
18352 procedure Set_Modular_Size (Bits : Int);
18353 -- Sets RM_Size to Bits, and Esize to normal word size above this
18355 ----------------------
18356 -- Set_Modular_Size --
18357 ----------------------
18359 procedure Set_Modular_Size (Bits : Int) is
18361 Set_RM_Size (T, UI_From_Int (Bits));
18366 elsif Bits <= 16 then
18367 Init_Esize (T, 16);
18369 elsif Bits <= 32 then
18370 Init_Esize (T, 32);
18373 Init_Esize (T, System_Max_Binary_Modulus_Power);
18376 if not Non_Binary_Modulus (T) and then Esize (T) = RM_Size (T) then
18377 Set_Is_Known_Valid (T);
18379 end Set_Modular_Size;
18381 -- Start of processing for Modular_Type_Declaration
18384 -- If the mod expression is (exactly) 2 * literal, where literal is
18385 -- 64 or less,then almost certainly the * was meant to be **. Warn.
18387 if Warn_On_Suspicious_Modulus_Value
18388 and then Nkind (Mod_Expr) = N_Op_Multiply
18389 and then Nkind (Left_Opnd (Mod_Expr)) = N_Integer_Literal
18390 and then Intval (Left_Opnd (Mod_Expr)) = Uint_2
18391 and then Nkind (Right_Opnd (Mod_Expr)) = N_Integer_Literal
18392 and then Intval (Right_Opnd (Mod_Expr)) <= Uint_64
18395 ("suspicious MOD value, was '*'* intended'??M?", Mod_Expr);
18398 -- Proceed with analysis of mod expression
18400 Analyze_And_Resolve (Mod_Expr, Any_Integer);
18402 Set_Ekind (T, E_Modular_Integer_Type);
18403 Init_Alignment (T);
18404 Set_Is_Constrained (T);
18406 if not Is_OK_Static_Expression (Mod_Expr) then
18407 Flag_Non_Static_Expr
18408 ("non-static expression used for modular type bound!", Mod_Expr);
18409 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18411 M_Val := Expr_Value (Mod_Expr);
18415 Error_Msg_N ("modulus value must be positive", Mod_Expr);
18416 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18419 if M_Val > 2 ** Standard_Long_Integer_Size then
18420 Check_Restriction (No_Long_Long_Integers, Mod_Expr);
18423 Set_Modulus (T, M_Val);
18425 -- Create bounds for the modular type based on the modulus given in
18426 -- the type declaration and then analyze and resolve those bounds.
18428 Set_Scalar_Range (T,
18429 Make_Range (Sloc (Mod_Expr),
18430 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
18431 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
18433 -- Properly analyze the literals for the range. We do this manually
18434 -- because we can't go calling Resolve, since we are resolving these
18435 -- bounds with the type, and this type is certainly not complete yet.
18437 Set_Etype (Low_Bound (Scalar_Range (T)), T);
18438 Set_Etype (High_Bound (Scalar_Range (T)), T);
18439 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
18440 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
18442 -- Loop through powers of two to find number of bits required
18444 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
18448 if M_Val = 2 ** Bits then
18449 Set_Modular_Size (Bits);
18454 elsif M_Val < 2 ** Bits then
18455 Check_SPARK_05_Restriction ("modulus should be a power of 2", T);
18456 Set_Non_Binary_Modulus (T);
18458 if Bits > System_Max_Nonbinary_Modulus_Power then
18459 Error_Msg_Uint_1 :=
18460 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
18462 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
18463 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18467 -- In the non-binary case, set size as per RM 13.3(55)
18469 Set_Modular_Size (Bits);
18476 -- If we fall through, then the size exceed System.Max_Binary_Modulus
18477 -- so we just signal an error and set the maximum size.
18479 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
18480 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
18482 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18483 Init_Alignment (T);
18485 end Modular_Type_Declaration;
18487 --------------------------
18488 -- New_Concatenation_Op --
18489 --------------------------
18491 procedure New_Concatenation_Op (Typ : Entity_Id) is
18492 Loc : constant Source_Ptr := Sloc (Typ);
18495 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
18496 -- Create abbreviated declaration for the formal of a predefined
18497 -- Operator 'Op' of type 'Typ'
18499 --------------------
18500 -- Make_Op_Formal --
18501 --------------------
18503 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
18504 Formal : Entity_Id;
18506 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
18507 Set_Etype (Formal, Typ);
18508 Set_Mechanism (Formal, Default_Mechanism);
18510 end Make_Op_Formal;
18512 -- Start of processing for New_Concatenation_Op
18515 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
18517 Set_Ekind (Op, E_Operator);
18518 Set_Scope (Op, Current_Scope);
18519 Set_Etype (Op, Typ);
18520 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
18521 Set_Is_Immediately_Visible (Op);
18522 Set_Is_Intrinsic_Subprogram (Op);
18523 Set_Has_Completion (Op);
18524 Append_Entity (Op, Current_Scope);
18526 Set_Name_Entity_Id (Name_Op_Concat, Op);
18528 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18529 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18530 end New_Concatenation_Op;
18532 -------------------------
18533 -- OK_For_Limited_Init --
18534 -------------------------
18536 -- ???Check all calls of this, and compare the conditions under which it's
18539 function OK_For_Limited_Init
18541 Exp : Node_Id) return Boolean
18544 return Is_CPP_Constructor_Call (Exp)
18545 or else (Ada_Version >= Ada_2005
18546 and then not Debug_Flag_Dot_L
18547 and then OK_For_Limited_Init_In_05 (Typ, Exp));
18548 end OK_For_Limited_Init;
18550 -------------------------------
18551 -- OK_For_Limited_Init_In_05 --
18552 -------------------------------
18554 function OK_For_Limited_Init_In_05
18556 Exp : Node_Id) return Boolean
18559 -- An object of a limited interface type can be initialized with any
18560 -- expression of a nonlimited descendant type.
18562 if Is_Class_Wide_Type (Typ)
18563 and then Is_Limited_Interface (Typ)
18564 and then not Is_Limited_Type (Etype (Exp))
18569 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
18570 -- case of limited aggregates (including extension aggregates), and
18571 -- function calls. The function call may have been given in prefixed
18572 -- notation, in which case the original node is an indexed component.
18573 -- If the function is parameterless, the original node was an explicit
18574 -- dereference. The function may also be parameterless, in which case
18575 -- the source node is just an identifier.
18577 case Nkind (Original_Node (Exp)) is
18578 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
18581 when N_Identifier =>
18582 return Present (Entity (Original_Node (Exp)))
18583 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
18585 when N_Qualified_Expression =>
18587 OK_For_Limited_Init_In_05
18588 (Typ, Expression (Original_Node (Exp)));
18590 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
18591 -- with a function call, the expander has rewritten the call into an
18592 -- N_Type_Conversion node to force displacement of the pointer to
18593 -- reference the component containing the secondary dispatch table.
18594 -- Otherwise a type conversion is not a legal context.
18595 -- A return statement for a build-in-place function returning a
18596 -- synchronized type also introduces an unchecked conversion.
18598 when N_Type_Conversion |
18599 N_Unchecked_Type_Conversion =>
18600 return not Comes_From_Source (Exp)
18602 OK_For_Limited_Init_In_05
18603 (Typ, Expression (Original_Node (Exp)));
18605 when N_Indexed_Component |
18606 N_Selected_Component |
18607 N_Explicit_Dereference =>
18608 return Nkind (Exp) = N_Function_Call;
18610 -- A use of 'Input is a function call, hence allowed. Normally the
18611 -- attribute will be changed to a call, but the attribute by itself
18612 -- can occur with -gnatc.
18614 when N_Attribute_Reference =>
18615 return Attribute_Name (Original_Node (Exp)) = Name_Input;
18617 -- For a case expression, all dependent expressions must be legal
18619 when N_Case_Expression =>
18624 Alt := First (Alternatives (Original_Node (Exp)));
18625 while Present (Alt) loop
18626 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
18636 -- For an if expression, all dependent expressions must be legal
18638 when N_If_Expression =>
18640 Then_Expr : constant Node_Id :=
18641 Next (First (Expressions (Original_Node (Exp))));
18642 Else_Expr : constant Node_Id := Next (Then_Expr);
18644 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
18646 OK_For_Limited_Init_In_05 (Typ, Else_Expr);
18652 end OK_For_Limited_Init_In_05;
18654 -------------------------------------------
18655 -- Ordinary_Fixed_Point_Type_Declaration --
18656 -------------------------------------------
18658 procedure Ordinary_Fixed_Point_Type_Declaration
18662 Loc : constant Source_Ptr := Sloc (Def);
18663 Delta_Expr : constant Node_Id := Delta_Expression (Def);
18664 RRS : constant Node_Id := Real_Range_Specification (Def);
18665 Implicit_Base : Entity_Id;
18672 Check_Restriction (No_Fixed_Point, Def);
18674 -- Create implicit base type
18677 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
18678 Set_Etype (Implicit_Base, Implicit_Base);
18680 -- Analyze and process delta expression
18682 Analyze_And_Resolve (Delta_Expr, Any_Real);
18684 Check_Delta_Expression (Delta_Expr);
18685 Delta_Val := Expr_Value_R (Delta_Expr);
18687 Set_Delta_Value (Implicit_Base, Delta_Val);
18689 -- Compute default small from given delta, which is the largest power
18690 -- of two that does not exceed the given delta value.
18700 if Delta_Val < Ureal_1 then
18701 while Delta_Val < Tmp loop
18702 Tmp := Tmp / Ureal_2;
18703 Scale := Scale + 1;
18708 Tmp := Tmp * Ureal_2;
18709 exit when Tmp > Delta_Val;
18710 Scale := Scale - 1;
18714 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
18717 Set_Small_Value (Implicit_Base, Small_Val);
18719 -- If no range was given, set a dummy range
18721 if RRS <= Empty_Or_Error then
18722 Low_Val := -Small_Val;
18723 High_Val := Small_Val;
18725 -- Otherwise analyze and process given range
18729 Low : constant Node_Id := Low_Bound (RRS);
18730 High : constant Node_Id := High_Bound (RRS);
18733 Analyze_And_Resolve (Low, Any_Real);
18734 Analyze_And_Resolve (High, Any_Real);
18735 Check_Real_Bound (Low);
18736 Check_Real_Bound (High);
18738 -- Obtain and set the range
18740 Low_Val := Expr_Value_R (Low);
18741 High_Val := Expr_Value_R (High);
18743 if Low_Val > High_Val then
18744 Error_Msg_NE ("??fixed point type& has null range", Def, T);
18749 -- The range for both the implicit base and the declared first subtype
18750 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
18751 -- set a temporary range in place. Note that the bounds of the base
18752 -- type will be widened to be symmetrical and to fill the available
18753 -- bits when the type is frozen.
18755 -- We could do this with all discrete types, and probably should, but
18756 -- we absolutely have to do it for fixed-point, since the end-points
18757 -- of the range and the size are determined by the small value, which
18758 -- could be reset before the freeze point.
18760 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
18761 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
18763 -- Complete definition of first subtype. The inheritance of the rep item
18764 -- chain ensures that SPARK-related pragmas are not clobbered when the
18765 -- ordinary fixed point type acts as a full view of a private type.
18767 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
18768 Set_Etype (T, Implicit_Base);
18769 Init_Size_Align (T);
18770 Inherit_Rep_Item_Chain (T, Implicit_Base);
18771 Set_Small_Value (T, Small_Val);
18772 Set_Delta_Value (T, Delta_Val);
18773 Set_Is_Constrained (T);
18774 end Ordinary_Fixed_Point_Type_Declaration;
18776 ----------------------------------
18777 -- Preanalyze_Assert_Expression --
18778 ----------------------------------
18780 procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id) is
18782 In_Assertion_Expr := In_Assertion_Expr + 1;
18783 Preanalyze_Spec_Expression (N, T);
18784 In_Assertion_Expr := In_Assertion_Expr - 1;
18785 end Preanalyze_Assert_Expression;
18787 -----------------------------------
18788 -- Preanalyze_Default_Expression --
18789 -----------------------------------
18791 procedure Preanalyze_Default_Expression (N : Node_Id; T : Entity_Id) is
18792 Save_In_Default_Expr : constant Boolean := In_Default_Expr;
18794 In_Default_Expr := True;
18795 Preanalyze_Spec_Expression (N, T);
18796 In_Default_Expr := Save_In_Default_Expr;
18797 end Preanalyze_Default_Expression;
18799 --------------------------------
18800 -- Preanalyze_Spec_Expression --
18801 --------------------------------
18803 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
18804 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
18806 In_Spec_Expression := True;
18807 Preanalyze_And_Resolve (N, T);
18808 In_Spec_Expression := Save_In_Spec_Expression;
18809 end Preanalyze_Spec_Expression;
18811 ----------------------------------------
18812 -- Prepare_Private_Subtype_Completion --
18813 ----------------------------------------
18815 procedure Prepare_Private_Subtype_Completion
18817 Related_Nod : Node_Id)
18819 Id_B : constant Entity_Id := Base_Type (Id);
18820 Full_B : Entity_Id := Full_View (Id_B);
18824 if Present (Full_B) then
18826 -- Get to the underlying full view if necessary
18828 if Is_Private_Type (Full_B)
18829 and then Present (Underlying_Full_View (Full_B))
18831 Full_B := Underlying_Full_View (Full_B);
18834 -- The Base_Type is already completed, we can complete the subtype
18835 -- now. We have to create a new entity with the same name, Thus we
18836 -- can't use Create_Itype.
18838 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
18839 Set_Is_Itype (Full);
18840 Set_Associated_Node_For_Itype (Full, Related_Nod);
18841 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
18844 -- The parent subtype may be private, but the base might not, in some
18845 -- nested instances. In that case, the subtype does not need to be
18846 -- exchanged. It would still be nice to make private subtypes and their
18847 -- bases consistent at all times ???
18849 if Is_Private_Type (Id_B) then
18850 Append_Elmt (Id, Private_Dependents (Id_B));
18852 end Prepare_Private_Subtype_Completion;
18854 ---------------------------
18855 -- Process_Discriminants --
18856 ---------------------------
18858 procedure Process_Discriminants
18860 Prev : Entity_Id := Empty)
18862 Elist : constant Elist_Id := New_Elmt_List;
18865 Discr_Number : Uint;
18866 Discr_Type : Entity_Id;
18867 Default_Present : Boolean := False;
18868 Default_Not_Present : Boolean := False;
18871 -- A composite type other than an array type can have discriminants.
18872 -- On entry, the current scope is the composite type.
18874 -- The discriminants are initially entered into the scope of the type
18875 -- via Enter_Name with the default Ekind of E_Void to prevent premature
18876 -- use, as explained at the end of this procedure.
18878 Discr := First (Discriminant_Specifications (N));
18879 while Present (Discr) loop
18880 Enter_Name (Defining_Identifier (Discr));
18882 -- For navigation purposes we add a reference to the discriminant
18883 -- in the entity for the type. If the current declaration is a
18884 -- completion, place references on the partial view. Otherwise the
18885 -- type is the current scope.
18887 if Present (Prev) then
18889 -- The references go on the partial view, if present. If the
18890 -- partial view has discriminants, the references have been
18891 -- generated already.
18893 if not Has_Discriminants (Prev) then
18894 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
18898 (Current_Scope, Defining_Identifier (Discr), 'd');
18901 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
18902 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
18904 -- Ada 2005 (AI-254)
18906 if Present (Access_To_Subprogram_Definition
18907 (Discriminant_Type (Discr)))
18908 and then Protected_Present (Access_To_Subprogram_Definition
18909 (Discriminant_Type (Discr)))
18912 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
18916 Find_Type (Discriminant_Type (Discr));
18917 Discr_Type := Etype (Discriminant_Type (Discr));
18919 if Error_Posted (Discriminant_Type (Discr)) then
18920 Discr_Type := Any_Type;
18924 -- Handling of discriminants that are access types
18926 if Is_Access_Type (Discr_Type) then
18928 -- Ada 2005 (AI-230): Access discriminant allowed in non-
18929 -- limited record types
18931 if Ada_Version < Ada_2005 then
18932 Check_Access_Discriminant_Requires_Limited
18933 (Discr, Discriminant_Type (Discr));
18936 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
18938 ("(Ada 83) access discriminant not allowed", Discr);
18941 -- If not access type, must be a discrete type
18943 elsif not Is_Discrete_Type (Discr_Type) then
18945 ("discriminants must have a discrete or access type",
18946 Discriminant_Type (Discr));
18949 Set_Etype (Defining_Identifier (Discr), Discr_Type);
18951 -- If a discriminant specification includes the assignment compound
18952 -- delimiter followed by an expression, the expression is the default
18953 -- expression of the discriminant; the default expression must be of
18954 -- the type of the discriminant. (RM 3.7.1) Since this expression is
18955 -- a default expression, we do the special preanalysis, since this
18956 -- expression does not freeze (see section "Handling of Default and
18957 -- Per-Object Expressions" in spec of package Sem).
18959 if Present (Expression (Discr)) then
18960 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
18964 if Nkind (N) = N_Formal_Type_Declaration then
18966 ("discriminant defaults not allowed for formal type",
18967 Expression (Discr));
18969 -- Flag an error for a tagged type with defaulted discriminants,
18970 -- excluding limited tagged types when compiling for Ada 2012
18971 -- (see AI05-0214).
18973 elsif Is_Tagged_Type (Current_Scope)
18974 and then (not Is_Limited_Type (Current_Scope)
18975 or else Ada_Version < Ada_2012)
18976 and then Comes_From_Source (N)
18978 -- Note: see similar test in Check_Or_Process_Discriminants, to
18979 -- handle the (illegal) case of the completion of an untagged
18980 -- view with discriminants with defaults by a tagged full view.
18981 -- We skip the check if Discr does not come from source, to
18982 -- account for the case of an untagged derived type providing
18983 -- defaults for a renamed discriminant from a private untagged
18984 -- ancestor with a tagged full view (ACATS B460006).
18986 if Ada_Version >= Ada_2012 then
18988 ("discriminants of nonlimited tagged type cannot have"
18990 Expression (Discr));
18993 ("discriminants of tagged type cannot have defaults",
18994 Expression (Discr));
18998 Default_Present := True;
18999 Append_Elmt (Expression (Discr), Elist);
19001 -- Tag the defining identifiers for the discriminants with
19002 -- their corresponding default expressions from the tree.
19004 Set_Discriminant_Default_Value
19005 (Defining_Identifier (Discr), Expression (Discr));
19008 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag
19009 -- gets set unless we can be sure that no range check is required.
19011 if (GNATprove_Mode or not Expander_Active)
19014 (Expression (Discr), Discr_Type, Assume_Valid => True)
19016 Set_Do_Range_Check (Expression (Discr));
19019 -- No default discriminant value given
19022 Default_Not_Present := True;
19025 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
19026 -- Discr_Type but with the null-exclusion attribute
19028 if Ada_Version >= Ada_2005 then
19030 -- Ada 2005 (AI-231): Static checks
19032 if Can_Never_Be_Null (Discr_Type) then
19033 Null_Exclusion_Static_Checks (Discr);
19035 elsif Is_Access_Type (Discr_Type)
19036 and then Null_Exclusion_Present (Discr)
19038 -- No need to check itypes because in their case this check
19039 -- was done at their point of creation
19041 and then not Is_Itype (Discr_Type)
19043 if Can_Never_Be_Null (Discr_Type) then
19045 ("`NOT NULL` not allowed (& already excludes null)",
19050 Set_Etype (Defining_Identifier (Discr),
19051 Create_Null_Excluding_Itype
19053 Related_Nod => Discr));
19055 -- Check for improper null exclusion if the type is otherwise
19056 -- legal for a discriminant.
19058 elsif Null_Exclusion_Present (Discr)
19059 and then Is_Discrete_Type (Discr_Type)
19062 ("null exclusion can only apply to an access type", Discr);
19065 -- Ada 2005 (AI-402): access discriminants of nonlimited types
19066 -- can't have defaults. Synchronized types, or types that are
19067 -- explicitly limited are fine, but special tests apply to derived
19068 -- types in generics: in a generic body we have to assume the
19069 -- worst, and therefore defaults are not allowed if the parent is
19070 -- a generic formal private type (see ACATS B370001).
19072 if Is_Access_Type (Discr_Type) and then Default_Present then
19073 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
19074 or else Is_Limited_Record (Current_Scope)
19075 or else Is_Concurrent_Type (Current_Scope)
19076 or else Is_Concurrent_Record_Type (Current_Scope)
19077 or else Ekind (Current_Scope) = E_Limited_Private_Type
19079 if not Is_Derived_Type (Current_Scope)
19080 or else not Is_Generic_Type (Etype (Current_Scope))
19081 or else not In_Package_Body (Scope (Etype (Current_Scope)))
19082 or else Limited_Present
19083 (Type_Definition (Parent (Current_Scope)))
19089 ("access discriminants of nonlimited types cannot "
19090 & "have defaults", Expression (Discr));
19093 elsif Present (Expression (Discr)) then
19095 ("(Ada 2005) access discriminants of nonlimited types "
19096 & "cannot have defaults", Expression (Discr));
19101 -- A discriminant cannot be effectively volatile. This check is only
19102 -- relevant when SPARK_Mode is on as it is not standard Ada legality
19103 -- rule (SPARK RM 7.1.3(6)).
19106 and then Is_Effectively_Volatile (Defining_Identifier (Discr))
19108 Error_Msg_N ("discriminant cannot be volatile", Discr);
19114 -- An element list consisting of the default expressions of the
19115 -- discriminants is constructed in the above loop and used to set
19116 -- the Discriminant_Constraint attribute for the type. If an object
19117 -- is declared of this (record or task) type without any explicit
19118 -- discriminant constraint given, this element list will form the
19119 -- actual parameters for the corresponding initialization procedure
19122 Set_Discriminant_Constraint (Current_Scope, Elist);
19123 Set_Stored_Constraint (Current_Scope, No_Elist);
19125 -- Default expressions must be provided either for all or for none
19126 -- of the discriminants of a discriminant part. (RM 3.7.1)
19128 if Default_Present and then Default_Not_Present then
19130 ("incomplete specification of defaults for discriminants", N);
19133 -- The use of the name of a discriminant is not allowed in default
19134 -- expressions of a discriminant part if the specification of the
19135 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
19137 -- To detect this, the discriminant names are entered initially with an
19138 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
19139 -- attempt to use a void entity (for example in an expression that is
19140 -- type-checked) produces the error message: premature usage. Now after
19141 -- completing the semantic analysis of the discriminant part, we can set
19142 -- the Ekind of all the discriminants appropriately.
19144 Discr := First (Discriminant_Specifications (N));
19145 Discr_Number := Uint_1;
19146 while Present (Discr) loop
19147 Id := Defining_Identifier (Discr);
19148 Set_Ekind (Id, E_Discriminant);
19149 Init_Component_Location (Id);
19151 Set_Discriminant_Number (Id, Discr_Number);
19153 -- Make sure this is always set, even in illegal programs
19155 Set_Corresponding_Discriminant (Id, Empty);
19157 -- Initialize the Original_Record_Component to the entity itself.
19158 -- Inherit_Components will propagate the right value to
19159 -- discriminants in derived record types.
19161 Set_Original_Record_Component (Id, Id);
19163 -- Create the discriminal for the discriminant
19165 Build_Discriminal (Id);
19168 Discr_Number := Discr_Number + 1;
19171 Set_Has_Discriminants (Current_Scope);
19172 end Process_Discriminants;
19174 -----------------------
19175 -- Process_Full_View --
19176 -----------------------
19178 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
19179 procedure Collect_Implemented_Interfaces
19181 Ifaces : Elist_Id);
19182 -- Ada 2005: Gather all the interfaces that Typ directly or
19183 -- inherently implements. Duplicate entries are not added to
19184 -- the list Ifaces.
19186 ------------------------------------
19187 -- Collect_Implemented_Interfaces --
19188 ------------------------------------
19190 procedure Collect_Implemented_Interfaces
19195 Iface_Elmt : Elmt_Id;
19198 -- Abstract interfaces are only associated with tagged record types
19200 if not Is_Tagged_Type (Typ) or else not Is_Record_Type (Typ) then
19204 -- Recursively climb to the ancestors
19206 if Etype (Typ) /= Typ
19208 -- Protect the frontend against wrong cyclic declarations like:
19210 -- type B is new A with private;
19211 -- type C is new A with private;
19213 -- type B is new C with null record;
19214 -- type C is new B with null record;
19216 and then Etype (Typ) /= Priv_T
19217 and then Etype (Typ) /= Full_T
19219 -- Keep separate the management of private type declarations
19221 if Ekind (Typ) = E_Record_Type_With_Private then
19223 -- Handle the following illegal usage:
19224 -- type Private_Type is tagged private;
19226 -- type Private_Type is new Type_Implementing_Iface;
19228 if Present (Full_View (Typ))
19229 and then Etype (Typ) /= Full_View (Typ)
19231 if Is_Interface (Etype (Typ)) then
19232 Append_Unique_Elmt (Etype (Typ), Ifaces);
19235 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19238 -- Non-private types
19241 if Is_Interface (Etype (Typ)) then
19242 Append_Unique_Elmt (Etype (Typ), Ifaces);
19245 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19249 -- Handle entities in the list of abstract interfaces
19251 if Present (Interfaces (Typ)) then
19252 Iface_Elmt := First_Elmt (Interfaces (Typ));
19253 while Present (Iface_Elmt) loop
19254 Iface := Node (Iface_Elmt);
19256 pragma Assert (Is_Interface (Iface));
19258 if not Contain_Interface (Iface, Ifaces) then
19259 Append_Elmt (Iface, Ifaces);
19260 Collect_Implemented_Interfaces (Iface, Ifaces);
19263 Next_Elmt (Iface_Elmt);
19266 end Collect_Implemented_Interfaces;
19270 Full_Indic : Node_Id;
19271 Full_Parent : Entity_Id;
19272 Priv_Parent : Entity_Id;
19274 -- Start of processing for Process_Full_View
19277 -- First some sanity checks that must be done after semantic
19278 -- decoration of the full view and thus cannot be placed with other
19279 -- similar checks in Find_Type_Name
19281 if not Is_Limited_Type (Priv_T)
19282 and then (Is_Limited_Type (Full_T)
19283 or else Is_Limited_Composite (Full_T))
19285 if In_Instance then
19289 ("completion of nonlimited type cannot be limited", Full_T);
19290 Explain_Limited_Type (Full_T, Full_T);
19293 elsif Is_Abstract_Type (Full_T)
19294 and then not Is_Abstract_Type (Priv_T)
19297 ("completion of nonabstract type cannot be abstract", Full_T);
19299 elsif Is_Tagged_Type (Priv_T)
19300 and then Is_Limited_Type (Priv_T)
19301 and then not Is_Limited_Type (Full_T)
19303 -- If pragma CPP_Class was applied to the private declaration
19304 -- propagate the limitedness to the full-view
19306 if Is_CPP_Class (Priv_T) then
19307 Set_Is_Limited_Record (Full_T);
19309 -- GNAT allow its own definition of Limited_Controlled to disobey
19310 -- this rule in order in ease the implementation. This test is safe
19311 -- because Root_Controlled is defined in a child of System that
19312 -- normal programs are not supposed to use.
19314 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
19315 Set_Is_Limited_Composite (Full_T);
19318 ("completion of limited tagged type must be limited", Full_T);
19321 elsif Is_Generic_Type (Priv_T) then
19322 Error_Msg_N ("generic type cannot have a completion", Full_T);
19325 -- Check that ancestor interfaces of private and full views are
19326 -- consistent. We omit this check for synchronized types because
19327 -- they are performed on the corresponding record type when frozen.
19329 if Ada_Version >= Ada_2005
19330 and then Is_Tagged_Type (Priv_T)
19331 and then Is_Tagged_Type (Full_T)
19332 and then not Is_Concurrent_Type (Full_T)
19336 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
19337 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
19340 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
19341 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
19343 -- Ada 2005 (AI-251): The partial view shall be a descendant of
19344 -- an interface type if and only if the full type is descendant
19345 -- of the interface type (AARM 7.3 (7.3/2)).
19347 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
19349 if Present (Iface) then
19351 ("interface in partial view& not implemented by full type "
19352 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19355 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
19357 if Present (Iface) then
19359 ("interface & not implemented by partial view "
19360 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19365 if Is_Tagged_Type (Priv_T)
19366 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19367 and then Is_Derived_Type (Full_T)
19369 Priv_Parent := Etype (Priv_T);
19371 -- The full view of a private extension may have been transformed
19372 -- into an unconstrained derived type declaration and a subtype
19373 -- declaration (see build_derived_record_type for details).
19375 if Nkind (N) = N_Subtype_Declaration then
19376 Full_Indic := Subtype_Indication (N);
19377 Full_Parent := Etype (Base_Type (Full_T));
19379 Full_Indic := Subtype_Indication (Type_Definition (N));
19380 Full_Parent := Etype (Full_T);
19383 -- Check that the parent type of the full type is a descendant of
19384 -- the ancestor subtype given in the private extension. If either
19385 -- entity has an Etype equal to Any_Type then we had some previous
19386 -- error situation [7.3(8)].
19388 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
19391 -- Ada 2005 (AI-251): Interfaces in the full type can be given in
19392 -- any order. Therefore we don't have to check that its parent must
19393 -- be a descendant of the parent of the private type declaration.
19395 elsif Is_Interface (Priv_Parent)
19396 and then Is_Interface (Full_Parent)
19400 -- Ada 2005 (AI-251): If the parent of the private type declaration
19401 -- is an interface there is no need to check that it is an ancestor
19402 -- of the associated full type declaration. The required tests for
19403 -- this case are performed by Build_Derived_Record_Type.
19405 elsif not Is_Interface (Base_Type (Priv_Parent))
19406 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
19409 ("parent of full type must descend from parent"
19410 & " of private extension", Full_Indic);
19412 -- First check a formal restriction, and then proceed with checking
19413 -- Ada rules. Since the formal restriction is not a serious error, we
19414 -- don't prevent further error detection for this check, hence the
19418 -- In formal mode, when completing a private extension the type
19419 -- named in the private part must be exactly the same as that
19420 -- named in the visible part.
19422 if Priv_Parent /= Full_Parent then
19423 Error_Msg_Name_1 := Chars (Priv_Parent);
19424 Check_SPARK_05_Restriction ("% expected", Full_Indic);
19427 -- Check the rules of 7.3(10): if the private extension inherits
19428 -- known discriminants, then the full type must also inherit those
19429 -- discriminants from the same (ancestor) type, and the parent
19430 -- subtype of the full type must be constrained if and only if
19431 -- the ancestor subtype of the private extension is constrained.
19433 if No (Discriminant_Specifications (Parent (Priv_T)))
19434 and then not Has_Unknown_Discriminants (Priv_T)
19435 and then Has_Discriminants (Base_Type (Priv_Parent))
19438 Priv_Indic : constant Node_Id :=
19439 Subtype_Indication (Parent (Priv_T));
19441 Priv_Constr : constant Boolean :=
19442 Is_Constrained (Priv_Parent)
19444 Nkind (Priv_Indic) = N_Subtype_Indication
19446 Is_Constrained (Entity (Priv_Indic));
19448 Full_Constr : constant Boolean :=
19449 Is_Constrained (Full_Parent)
19451 Nkind (Full_Indic) = N_Subtype_Indication
19453 Is_Constrained (Entity (Full_Indic));
19455 Priv_Discr : Entity_Id;
19456 Full_Discr : Entity_Id;
19459 Priv_Discr := First_Discriminant (Priv_Parent);
19460 Full_Discr := First_Discriminant (Full_Parent);
19461 while Present (Priv_Discr) and then Present (Full_Discr) loop
19462 if Original_Record_Component (Priv_Discr) =
19463 Original_Record_Component (Full_Discr)
19465 Corresponding_Discriminant (Priv_Discr) =
19466 Corresponding_Discriminant (Full_Discr)
19473 Next_Discriminant (Priv_Discr);
19474 Next_Discriminant (Full_Discr);
19477 if Present (Priv_Discr) or else Present (Full_Discr) then
19479 ("full view must inherit discriminants of the parent"
19480 & " type used in the private extension", Full_Indic);
19482 elsif Priv_Constr and then not Full_Constr then
19484 ("parent subtype of full type must be constrained",
19487 elsif Full_Constr and then not Priv_Constr then
19489 ("parent subtype of full type must be unconstrained",
19494 -- Check the rules of 7.3(12): if a partial view has neither
19495 -- known or unknown discriminants, then the full type
19496 -- declaration shall define a definite subtype.
19498 elsif not Has_Unknown_Discriminants (Priv_T)
19499 and then not Has_Discriminants (Priv_T)
19500 and then not Is_Constrained (Full_T)
19503 ("full view must define a constrained type if partial view"
19504 & " has no discriminants", Full_T);
19507 -- ??????? Do we implement the following properly ?????
19508 -- If the ancestor subtype of a private extension has constrained
19509 -- discriminants, then the parent subtype of the full view shall
19510 -- impose a statically matching constraint on those discriminants
19515 -- For untagged types, verify that a type without discriminants is
19516 -- not completed with an unconstrained type. A separate error message
19517 -- is produced if the full type has defaulted discriminants.
19519 if not Is_Indefinite_Subtype (Priv_T)
19520 and then Is_Indefinite_Subtype (Full_T)
19522 Error_Msg_Sloc := Sloc (Parent (Priv_T));
19524 ("full view of& not compatible with declaration#",
19527 if not Is_Tagged_Type (Full_T) then
19529 ("\one is constrained, the other unconstrained", Full_T);
19534 -- AI-419: verify that the use of "limited" is consistent
19537 Orig_Decl : constant Node_Id := Original_Node (N);
19540 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19541 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
19543 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
19545 if not Limited_Present (Parent (Priv_T))
19546 and then not Synchronized_Present (Parent (Priv_T))
19547 and then Limited_Present (Type_Definition (Orig_Decl))
19550 ("full view of non-limited extension cannot be limited", N);
19552 -- Conversely, if the partial view carries the limited keyword,
19553 -- the full view must as well, even if it may be redundant.
19555 elsif Limited_Present (Parent (Priv_T))
19556 and then not Limited_Present (Type_Definition (Orig_Decl))
19559 ("full view of limited extension must be explicitly limited",
19565 -- Ada 2005 (AI-443): A synchronized private extension must be
19566 -- completed by a task or protected type.
19568 if Ada_Version >= Ada_2005
19569 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19570 and then Synchronized_Present (Parent (Priv_T))
19571 and then not Is_Concurrent_Type (Full_T)
19573 Error_Msg_N ("full view of synchronized extension must " &
19574 "be synchronized type", N);
19577 -- Ada 2005 AI-363: if the full view has discriminants with
19578 -- defaults, it is illegal to declare constrained access subtypes
19579 -- whose designated type is the current type. This allows objects
19580 -- of the type that are declared in the heap to be unconstrained.
19582 if not Has_Unknown_Discriminants (Priv_T)
19583 and then not Has_Discriminants (Priv_T)
19584 and then Has_Discriminants (Full_T)
19586 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
19588 Set_Has_Constrained_Partial_View (Full_T);
19589 Set_Has_Constrained_Partial_View (Priv_T);
19592 -- Create a full declaration for all its subtypes recorded in
19593 -- Private_Dependents and swap them similarly to the base type. These
19594 -- are subtypes that have been define before the full declaration of
19595 -- the private type. We also swap the entry in Private_Dependents list
19596 -- so we can properly restore the private view on exit from the scope.
19599 Priv_Elmt : Elmt_Id;
19600 Priv_Scop : Entity_Id;
19605 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
19606 while Present (Priv_Elmt) loop
19607 Priv := Node (Priv_Elmt);
19608 Priv_Scop := Scope (Priv);
19610 if Ekind_In (Priv, E_Private_Subtype,
19611 E_Limited_Private_Subtype,
19612 E_Record_Subtype_With_Private)
19614 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
19615 Set_Is_Itype (Full);
19616 Set_Parent (Full, Parent (Priv));
19617 Set_Associated_Node_For_Itype (Full, N);
19619 -- Now we need to complete the private subtype, but since the
19620 -- base type has already been swapped, we must also swap the
19621 -- subtypes (and thus, reverse the arguments in the call to
19622 -- Complete_Private_Subtype). Also note that we may need to
19623 -- re-establish the scope of the private subtype.
19625 Copy_And_Swap (Priv, Full);
19627 if not In_Open_Scopes (Priv_Scop) then
19628 Push_Scope (Priv_Scop);
19631 -- Reset Priv_Scop to Empty to indicate no scope was pushed
19633 Priv_Scop := Empty;
19636 Complete_Private_Subtype (Full, Priv, Full_T, N);
19638 if Present (Priv_Scop) then
19642 Replace_Elmt (Priv_Elmt, Full);
19645 Next_Elmt (Priv_Elmt);
19649 -- If the private view was tagged, copy the new primitive operations
19650 -- from the private view to the full view.
19652 if Is_Tagged_Type (Full_T) then
19654 Disp_Typ : Entity_Id;
19655 Full_List : Elist_Id;
19657 Prim_Elmt : Elmt_Id;
19658 Priv_List : Elist_Id;
19662 L : Elist_Id) return Boolean;
19663 -- Determine whether list L contains element E
19671 L : Elist_Id) return Boolean
19673 List_Elmt : Elmt_Id;
19676 List_Elmt := First_Elmt (L);
19677 while Present (List_Elmt) loop
19678 if Node (List_Elmt) = E then
19682 Next_Elmt (List_Elmt);
19688 -- Start of processing
19691 if Is_Tagged_Type (Priv_T) then
19692 Priv_List := Primitive_Operations (Priv_T);
19693 Prim_Elmt := First_Elmt (Priv_List);
19695 -- In the case of a concurrent type completing a private tagged
19696 -- type, primitives may have been declared in between the two
19697 -- views. These subprograms need to be wrapped the same way
19698 -- entries and protected procedures are handled because they
19699 -- cannot be directly shared by the two views.
19701 if Is_Concurrent_Type (Full_T) then
19703 Conc_Typ : constant Entity_Id :=
19704 Corresponding_Record_Type (Full_T);
19705 Curr_Nod : Node_Id := Parent (Conc_Typ);
19706 Wrap_Spec : Node_Id;
19709 while Present (Prim_Elmt) loop
19710 Prim := Node (Prim_Elmt);
19712 if Comes_From_Source (Prim)
19713 and then not Is_Abstract_Subprogram (Prim)
19716 Make_Subprogram_Declaration (Sloc (Prim),
19720 Obj_Typ => Conc_Typ,
19722 Parameter_Specifications (
19725 Insert_After (Curr_Nod, Wrap_Spec);
19726 Curr_Nod := Wrap_Spec;
19728 Analyze (Wrap_Spec);
19731 Next_Elmt (Prim_Elmt);
19737 -- For non-concurrent types, transfer explicit primitives, but
19738 -- omit those inherited from the parent of the private view
19739 -- since they will be re-inherited later on.
19742 Full_List := Primitive_Operations (Full_T);
19744 while Present (Prim_Elmt) loop
19745 Prim := Node (Prim_Elmt);
19747 if Comes_From_Source (Prim)
19748 and then not Contains (Prim, Full_List)
19750 Append_Elmt (Prim, Full_List);
19753 Next_Elmt (Prim_Elmt);
19757 -- Untagged private view
19760 Full_List := Primitive_Operations (Full_T);
19762 -- In this case the partial view is untagged, so here we locate
19763 -- all of the earlier primitives that need to be treated as
19764 -- dispatching (those that appear between the two views). Note
19765 -- that these additional operations must all be new operations
19766 -- (any earlier operations that override inherited operations
19767 -- of the full view will already have been inserted in the
19768 -- primitives list, marked by Check_Operation_From_Private_View
19769 -- as dispatching. Note that implicit "/=" operators are
19770 -- excluded from being added to the primitives list since they
19771 -- shouldn't be treated as dispatching (tagged "/=" is handled
19774 Prim := Next_Entity (Full_T);
19775 while Present (Prim) and then Prim /= Priv_T loop
19776 if Ekind_In (Prim, E_Procedure, E_Function) then
19777 Disp_Typ := Find_Dispatching_Type (Prim);
19779 if Disp_Typ = Full_T
19780 and then (Chars (Prim) /= Name_Op_Ne
19781 or else Comes_From_Source (Prim))
19783 Check_Controlling_Formals (Full_T, Prim);
19785 if not Is_Dispatching_Operation (Prim) then
19786 Append_Elmt (Prim, Full_List);
19787 Set_Is_Dispatching_Operation (Prim, True);
19788 Set_DT_Position_Value (Prim, No_Uint);
19791 elsif Is_Dispatching_Operation (Prim)
19792 and then Disp_Typ /= Full_T
19795 -- Verify that it is not otherwise controlled by a
19796 -- formal or a return value of type T.
19798 Check_Controlling_Formals (Disp_Typ, Prim);
19802 Next_Entity (Prim);
19806 -- For the tagged case, the two views can share the same primitive
19807 -- operations list and the same class-wide type. Update attributes
19808 -- of the class-wide type which depend on the full declaration.
19810 if Is_Tagged_Type (Priv_T) then
19811 Set_Direct_Primitive_Operations (Priv_T, Full_List);
19812 Set_Class_Wide_Type
19813 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
19815 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
19817 (Class_Wide_Type (Priv_T), Has_Protected (Full_T));
19822 -- Ada 2005 AI 161: Check preelaborable initialization consistency
19824 if Known_To_Have_Preelab_Init (Priv_T) then
19826 -- Case where there is a pragma Preelaborable_Initialization. We
19827 -- always allow this in predefined units, which is cheating a bit,
19828 -- but it means we don't have to struggle to meet the requirements in
19829 -- the RM for having Preelaborable Initialization. Otherwise we
19830 -- require that the type meets the RM rules. But we can't check that
19831 -- yet, because of the rule about overriding Initialize, so we simply
19832 -- set a flag that will be checked at freeze time.
19834 if not In_Predefined_Unit (Full_T) then
19835 Set_Must_Have_Preelab_Init (Full_T);
19839 -- If pragma CPP_Class was applied to the private type declaration,
19840 -- propagate it now to the full type declaration.
19842 if Is_CPP_Class (Priv_T) then
19843 Set_Is_CPP_Class (Full_T);
19844 Set_Convention (Full_T, Convention_CPP);
19846 -- Check that components of imported CPP types do not have default
19849 Check_CPP_Type_Has_No_Defaults (Full_T);
19852 -- If the private view has user specified stream attributes, then so has
19855 -- Why the test, how could these flags be already set in Full_T ???
19857 if Has_Specified_Stream_Read (Priv_T) then
19858 Set_Has_Specified_Stream_Read (Full_T);
19861 if Has_Specified_Stream_Write (Priv_T) then
19862 Set_Has_Specified_Stream_Write (Full_T);
19865 if Has_Specified_Stream_Input (Priv_T) then
19866 Set_Has_Specified_Stream_Input (Full_T);
19869 if Has_Specified_Stream_Output (Priv_T) then
19870 Set_Has_Specified_Stream_Output (Full_T);
19873 -- Propagate the attributes related to pragma Default_Initial_Condition
19874 -- from the private to the full view. Note that both flags are mutually
19877 if Has_Default_Init_Cond (Priv_T)
19878 or else Has_Inherited_Default_Init_Cond (Priv_T)
19880 Propagate_Default_Init_Cond_Attributes
19881 (From_Typ => Priv_T,
19883 Private_To_Full_View => True);
19885 -- In the case where the full view is derived from another private type,
19886 -- the attributes related to pragma Default_Initial_Condition must be
19887 -- propagated from the full to the private view to maintain consistency
19891 -- type Parent_Typ is private
19892 -- with Default_Initial_Condition ...;
19894 -- type Parent_Typ is ...;
19897 -- with Pack; use Pack;
19898 -- package Pack_2 is
19899 -- type Deriv_Typ is private; -- must inherit
19901 -- type Deriv_Typ is new Parent_Typ; -- must inherit
19904 elsif Has_Default_Init_Cond (Full_T)
19905 or else Has_Inherited_Default_Init_Cond (Full_T)
19907 Propagate_Default_Init_Cond_Attributes
19908 (From_Typ => Full_T,
19910 Private_To_Full_View => True);
19913 -- Propagate the attributes related to pragma Ghost from the private to
19916 if Is_Ghost_Entity (Priv_T) then
19917 Set_Is_Ghost_Entity (Full_T);
19919 -- The Ghost policy in effect at the point of declaration and at the
19920 -- point of completion must match (SPARK RM 6.9(15)).
19922 Check_Ghost_Completion (Priv_T, Full_T);
19924 -- In the case where the private view of a tagged type lacks a parent
19925 -- type and is subject to pragma Ghost, ensure that the parent type
19926 -- specified by the full view is also Ghost (SPARK RM 6.9(9)).
19928 if Is_Derived_Type (Full_T) then
19929 Check_Ghost_Derivation (Full_T);
19933 -- Propagate invariants to full type
19935 if Has_Invariants (Priv_T) then
19936 Set_Has_Invariants (Full_T);
19937 Set_Invariant_Procedure (Full_T, Invariant_Procedure (Priv_T));
19940 if Has_Inheritable_Invariants (Priv_T) then
19941 Set_Has_Inheritable_Invariants (Full_T);
19944 -- Check hidden inheritance of class-wide type invariants
19946 if Ada_Version >= Ada_2012
19947 and then not Has_Inheritable_Invariants (Full_T)
19948 and then In_Private_Part (Current_Scope)
19949 and then Has_Interfaces (Full_T)
19956 Collect_Interfaces (Full_T, Ifaces, Exclude_Parents => True);
19958 AI := First_Elmt (Ifaces);
19959 while Present (AI) loop
19960 if Has_Inheritable_Invariants (Node (AI)) then
19962 ("hidden inheritance of class-wide type invariants " &
19972 -- Propagate predicates to full type, and predicate function if already
19973 -- defined. It is not clear that this can actually happen? the partial
19974 -- view cannot be frozen yet, and the predicate function has not been
19975 -- built. Still it is a cheap check and seems safer to make it.
19977 if Has_Predicates (Priv_T) then
19978 if Present (Predicate_Function (Priv_T)) then
19979 Set_Predicate_Function (Full_T, Predicate_Function (Priv_T));
19982 Set_Has_Predicates (Full_T);
19984 end Process_Full_View;
19986 -----------------------------------
19987 -- Process_Incomplete_Dependents --
19988 -----------------------------------
19990 procedure Process_Incomplete_Dependents
19992 Full_T : Entity_Id;
19995 Inc_Elmt : Elmt_Id;
19996 Priv_Dep : Entity_Id;
19997 New_Subt : Entity_Id;
19999 Disc_Constraint : Elist_Id;
20002 if No (Private_Dependents (Inc_T)) then
20006 -- Itypes that may be generated by the completion of an incomplete
20007 -- subtype are not used by the back-end and not attached to the tree.
20008 -- They are created only for constraint-checking purposes.
20010 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
20011 while Present (Inc_Elmt) loop
20012 Priv_Dep := Node (Inc_Elmt);
20014 if Ekind (Priv_Dep) = E_Subprogram_Type then
20016 -- An Access_To_Subprogram type may have a return type or a
20017 -- parameter type that is incomplete. Replace with the full view.
20019 if Etype (Priv_Dep) = Inc_T then
20020 Set_Etype (Priv_Dep, Full_T);
20024 Formal : Entity_Id;
20027 Formal := First_Formal (Priv_Dep);
20028 while Present (Formal) loop
20029 if Etype (Formal) = Inc_T then
20030 Set_Etype (Formal, Full_T);
20033 Next_Formal (Formal);
20037 elsif Is_Overloadable (Priv_Dep) then
20039 -- If a subprogram in the incomplete dependents list is primitive
20040 -- for a tagged full type then mark it as a dispatching operation,
20041 -- check whether it overrides an inherited subprogram, and check
20042 -- restrictions on its controlling formals. Note that a protected
20043 -- operation is never dispatching: only its wrapper operation
20044 -- (which has convention Ada) is.
20046 if Is_Tagged_Type (Full_T)
20047 and then Is_Primitive (Priv_Dep)
20048 and then Convention (Priv_Dep) /= Convention_Protected
20050 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
20051 Set_Is_Dispatching_Operation (Priv_Dep);
20052 Check_Controlling_Formals (Full_T, Priv_Dep);
20055 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
20057 -- Can happen during processing of a body before the completion
20058 -- of a TA type. Ignore, because spec is also on dependent list.
20062 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
20063 -- corresponding subtype of the full view.
20065 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
20066 Set_Subtype_Indication
20067 (Parent (Priv_Dep), New_Occurrence_Of (Full_T, Sloc (Priv_Dep)));
20068 Set_Etype (Priv_Dep, Full_T);
20069 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
20070 Set_Analyzed (Parent (Priv_Dep), False);
20072 -- Reanalyze the declaration, suppressing the call to
20073 -- Enter_Name to avoid duplicate names.
20075 Analyze_Subtype_Declaration
20076 (N => Parent (Priv_Dep),
20079 -- Dependent is a subtype
20082 -- We build a new subtype indication using the full view of the
20083 -- incomplete parent. The discriminant constraints have been
20084 -- elaborated already at the point of the subtype declaration.
20086 New_Subt := Create_Itype (E_Void, N);
20088 if Has_Discriminants (Full_T) then
20089 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
20091 Disc_Constraint := No_Elist;
20094 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
20095 Set_Full_View (Priv_Dep, New_Subt);
20098 Next_Elmt (Inc_Elmt);
20100 end Process_Incomplete_Dependents;
20102 --------------------------------
20103 -- Process_Range_Expr_In_Decl --
20104 --------------------------------
20106 procedure Process_Range_Expr_In_Decl
20109 Subtyp : Entity_Id := Empty;
20110 Check_List : List_Id := Empty_List;
20111 R_Check_Off : Boolean := False;
20112 In_Iter_Schm : Boolean := False)
20115 R_Checks : Check_Result;
20116 Insert_Node : Node_Id;
20117 Def_Id : Entity_Id;
20120 Analyze_And_Resolve (R, Base_Type (T));
20122 if Nkind (R) = N_Range then
20124 -- In SPARK, all ranges should be static, with the exception of the
20125 -- discrete type definition of a loop parameter specification.
20127 if not In_Iter_Schm
20128 and then not Is_OK_Static_Range (R)
20130 Check_SPARK_05_Restriction ("range should be static", R);
20133 Lo := Low_Bound (R);
20134 Hi := High_Bound (R);
20136 -- Validity checks on the range of a quantified expression are
20137 -- delayed until the construct is transformed into a loop.
20139 if Nkind (Parent (R)) = N_Loop_Parameter_Specification
20140 and then Nkind (Parent (Parent (R))) = N_Quantified_Expression
20144 -- We need to ensure validity of the bounds here, because if we
20145 -- go ahead and do the expansion, then the expanded code will get
20146 -- analyzed with range checks suppressed and we miss the check.
20148 -- WARNING: The capture of the range bounds with xxx_FIRST/_LAST and
20149 -- the temporaries generated by routine Remove_Side_Effects by means
20150 -- of validity checks must use the same names. When a range appears
20151 -- in the parent of a generic, the range is processed with checks
20152 -- disabled as part of the generic context and with checks enabled
20153 -- for code generation purposes. This leads to link issues as the
20154 -- generic contains references to xxx_FIRST/_LAST, but the inlined
20155 -- template sees the temporaries generated by Remove_Side_Effects.
20158 Validity_Check_Range (R, Subtyp);
20161 -- If there were errors in the declaration, try and patch up some
20162 -- common mistakes in the bounds. The cases handled are literals
20163 -- which are Integer where the expected type is Real and vice versa.
20164 -- These corrections allow the compilation process to proceed further
20165 -- along since some basic assumptions of the format of the bounds
20168 if Etype (R) = Any_Type then
20169 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
20171 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
20173 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
20175 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
20177 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
20179 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
20181 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
20183 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
20190 -- If the bounds of the range have been mistakenly given as string
20191 -- literals (perhaps in place of character literals), then an error
20192 -- has already been reported, but we rewrite the string literal as a
20193 -- bound of the range's type to avoid blowups in later processing
20194 -- that looks at static values.
20196 if Nkind (Lo) = N_String_Literal then
20198 Make_Attribute_Reference (Sloc (Lo),
20199 Prefix => New_Occurrence_Of (T, Sloc (Lo)),
20200 Attribute_Name => Name_First));
20201 Analyze_And_Resolve (Lo);
20204 if Nkind (Hi) = N_String_Literal then
20206 Make_Attribute_Reference (Sloc (Hi),
20207 Prefix => New_Occurrence_Of (T, Sloc (Hi)),
20208 Attribute_Name => Name_First));
20209 Analyze_And_Resolve (Hi);
20212 -- If bounds aren't scalar at this point then exit, avoiding
20213 -- problems with further processing of the range in this procedure.
20215 if not Is_Scalar_Type (Etype (Lo)) then
20219 -- Resolve (actually Sem_Eval) has checked that the bounds are in
20220 -- then range of the base type. Here we check whether the bounds
20221 -- are in the range of the subtype itself. Note that if the bounds
20222 -- represent the null range the Constraint_Error exception should
20225 -- ??? The following code should be cleaned up as follows
20227 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
20228 -- is done in the call to Range_Check (R, T); below
20230 -- 2. The use of R_Check_Off should be investigated and possibly
20231 -- removed, this would clean up things a bit.
20233 if Is_Null_Range (Lo, Hi) then
20237 -- Capture values of bounds and generate temporaries for them
20238 -- if needed, before applying checks, since checks may cause
20239 -- duplication of the expression without forcing evaluation.
20241 -- The forced evaluation removes side effects from expressions,
20242 -- which should occur also in GNATprove mode. Otherwise, we end up
20243 -- with unexpected insertions of actions at places where this is
20244 -- not supposed to occur, e.g. on default parameters of a call.
20246 if Expander_Active or GNATprove_Mode then
20248 -- Call Force_Evaluation to create declarations as needed to
20249 -- deal with side effects, and also create typ_FIRST/LAST
20250 -- entities for bounds if we have a subtype name.
20252 -- Note: we do this transformation even if expansion is not
20253 -- active if we are in GNATprove_Mode since the transformation
20254 -- is in general required to ensure that the resulting tree has
20255 -- proper Ada semantics.
20258 (Lo, Related_Id => Subtyp, Is_Low_Bound => True);
20260 (Hi, Related_Id => Subtyp, Is_High_Bound => True);
20263 -- We use a flag here instead of suppressing checks on the type
20264 -- because the type we check against isn't necessarily the place
20265 -- where we put the check.
20267 if not R_Check_Off then
20268 R_Checks := Get_Range_Checks (R, T);
20270 -- Look up tree to find an appropriate insertion point. We
20271 -- can't just use insert_actions because later processing
20272 -- depends on the insertion node. Prior to Ada 2012 the
20273 -- insertion point could only be a declaration or a loop, but
20274 -- quantified expressions can appear within any context in an
20275 -- expression, and the insertion point can be any statement,
20276 -- pragma, or declaration.
20278 Insert_Node := Parent (R);
20279 while Present (Insert_Node) loop
20281 Nkind (Insert_Node) in N_Declaration
20284 (Insert_Node, N_Component_Declaration,
20285 N_Loop_Parameter_Specification,
20286 N_Function_Specification,
20287 N_Procedure_Specification);
20289 exit when Nkind (Insert_Node) in N_Later_Decl_Item
20290 or else Nkind (Insert_Node) in
20291 N_Statement_Other_Than_Procedure_Call
20292 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
20295 Insert_Node := Parent (Insert_Node);
20298 -- Why would Type_Decl not be present??? Without this test,
20299 -- short regression tests fail.
20301 if Present (Insert_Node) then
20303 -- Case of loop statement. Verify that the range is part
20304 -- of the subtype indication of the iteration scheme.
20306 if Nkind (Insert_Node) = N_Loop_Statement then
20311 Indic := Parent (R);
20312 while Present (Indic)
20313 and then Nkind (Indic) /= N_Subtype_Indication
20315 Indic := Parent (Indic);
20318 if Present (Indic) then
20319 Def_Id := Etype (Subtype_Mark (Indic));
20321 Insert_Range_Checks
20325 Sloc (Insert_Node),
20327 Do_Before => True);
20331 -- Insertion before a declaration. If the declaration
20332 -- includes discriminants, the list of applicable checks
20333 -- is given by the caller.
20335 elsif Nkind (Insert_Node) in N_Declaration then
20336 Def_Id := Defining_Identifier (Insert_Node);
20338 if (Ekind (Def_Id) = E_Record_Type
20339 and then Depends_On_Discriminant (R))
20341 (Ekind (Def_Id) = E_Protected_Type
20342 and then Has_Discriminants (Def_Id))
20344 Append_Range_Checks
20346 Check_List, Def_Id, Sloc (Insert_Node), R);
20349 Insert_Range_Checks
20351 Insert_Node, Def_Id, Sloc (Insert_Node), R);
20355 -- Insertion before a statement. Range appears in the
20356 -- context of a quantified expression. Insertion will
20357 -- take place when expression is expanded.
20366 -- Case of other than an explicit N_Range node
20368 -- The forced evaluation removes side effects from expressions, which
20369 -- should occur also in GNATprove mode. Otherwise, we end up with
20370 -- unexpected insertions of actions at places where this is not
20371 -- supposed to occur, e.g. on default parameters of a call.
20373 elsif Expander_Active or GNATprove_Mode then
20374 Get_Index_Bounds (R, Lo, Hi);
20375 Force_Evaluation (Lo);
20376 Force_Evaluation (Hi);
20378 end Process_Range_Expr_In_Decl;
20380 --------------------------------------
20381 -- Process_Real_Range_Specification --
20382 --------------------------------------
20384 procedure Process_Real_Range_Specification (Def : Node_Id) is
20385 Spec : constant Node_Id := Real_Range_Specification (Def);
20388 Err : Boolean := False;
20390 procedure Analyze_Bound (N : Node_Id);
20391 -- Analyze and check one bound
20393 -------------------
20394 -- Analyze_Bound --
20395 -------------------
20397 procedure Analyze_Bound (N : Node_Id) is
20399 Analyze_And_Resolve (N, Any_Real);
20401 if not Is_OK_Static_Expression (N) then
20402 Flag_Non_Static_Expr
20403 ("bound in real type definition is not static!", N);
20408 -- Start of processing for Process_Real_Range_Specification
20411 if Present (Spec) then
20412 Lo := Low_Bound (Spec);
20413 Hi := High_Bound (Spec);
20414 Analyze_Bound (Lo);
20415 Analyze_Bound (Hi);
20417 -- If error, clear away junk range specification
20420 Set_Real_Range_Specification (Def, Empty);
20423 end Process_Real_Range_Specification;
20425 ---------------------
20426 -- Process_Subtype --
20427 ---------------------
20429 function Process_Subtype
20431 Related_Nod : Node_Id;
20432 Related_Id : Entity_Id := Empty;
20433 Suffix : Character := ' ') return Entity_Id
20436 Def_Id : Entity_Id;
20437 Error_Node : Node_Id;
20438 Full_View_Id : Entity_Id;
20439 Subtype_Mark_Id : Entity_Id;
20441 May_Have_Null_Exclusion : Boolean;
20443 procedure Check_Incomplete (T : Entity_Id);
20444 -- Called to verify that an incomplete type is not used prematurely
20446 ----------------------
20447 -- Check_Incomplete --
20448 ----------------------
20450 procedure Check_Incomplete (T : Entity_Id) is
20452 -- Ada 2005 (AI-412): Incomplete subtypes are legal
20454 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
20456 not (Ada_Version >= Ada_2005
20458 (Nkind (Parent (T)) = N_Subtype_Declaration
20459 or else (Nkind (Parent (T)) = N_Subtype_Indication
20460 and then Nkind (Parent (Parent (T))) =
20461 N_Subtype_Declaration)))
20463 Error_Msg_N ("invalid use of type before its full declaration", T);
20465 end Check_Incomplete;
20467 -- Start of processing for Process_Subtype
20470 -- Case of no constraints present
20472 if Nkind (S) /= N_Subtype_Indication then
20474 Check_Incomplete (S);
20477 -- Ada 2005 (AI-231): Static check
20479 if Ada_Version >= Ada_2005
20480 and then Present (P)
20481 and then Null_Exclusion_Present (P)
20482 and then Nkind (P) /= N_Access_To_Object_Definition
20483 and then not Is_Access_Type (Entity (S))
20485 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
20488 -- The following is ugly, can't we have a range or even a flag???
20490 May_Have_Null_Exclusion :=
20491 Nkind_In (P, N_Access_Definition,
20492 N_Access_Function_Definition,
20493 N_Access_Procedure_Definition,
20494 N_Access_To_Object_Definition,
20496 N_Component_Definition)
20498 Nkind_In (P, N_Derived_Type_Definition,
20499 N_Discriminant_Specification,
20500 N_Formal_Object_Declaration,
20501 N_Object_Declaration,
20502 N_Object_Renaming_Declaration,
20503 N_Parameter_Specification,
20504 N_Subtype_Declaration);
20506 -- Create an Itype that is a duplicate of Entity (S) but with the
20507 -- null-exclusion attribute.
20509 if May_Have_Null_Exclusion
20510 and then Is_Access_Type (Entity (S))
20511 and then Null_Exclusion_Present (P)
20513 -- No need to check the case of an access to object definition.
20514 -- It is correct to define double not-null pointers.
20517 -- type Not_Null_Int_Ptr is not null access Integer;
20518 -- type Acc is not null access Not_Null_Int_Ptr;
20520 and then Nkind (P) /= N_Access_To_Object_Definition
20522 if Can_Never_Be_Null (Entity (S)) then
20523 case Nkind (Related_Nod) is
20524 when N_Full_Type_Declaration =>
20525 if Nkind (Type_Definition (Related_Nod))
20526 in N_Array_Type_Definition
20530 (Component_Definition
20531 (Type_Definition (Related_Nod)));
20534 Subtype_Indication (Type_Definition (Related_Nod));
20537 when N_Subtype_Declaration =>
20538 Error_Node := Subtype_Indication (Related_Nod);
20540 when N_Object_Declaration =>
20541 Error_Node := Object_Definition (Related_Nod);
20543 when N_Component_Declaration =>
20545 Subtype_Indication (Component_Definition (Related_Nod));
20547 when N_Allocator =>
20548 Error_Node := Expression (Related_Nod);
20551 pragma Assert (False);
20552 Error_Node := Related_Nod;
20556 ("`NOT NULL` not allowed (& already excludes null)",
20562 Create_Null_Excluding_Itype
20564 Related_Nod => P));
20565 Set_Entity (S, Etype (S));
20570 -- Case of constraint present, so that we have an N_Subtype_Indication
20571 -- node (this node is created only if constraints are present).
20574 Find_Type (Subtype_Mark (S));
20576 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
20578 (Nkind (Parent (S)) = N_Subtype_Declaration
20579 and then Is_Itype (Defining_Identifier (Parent (S))))
20581 Check_Incomplete (Subtype_Mark (S));
20585 Subtype_Mark_Id := Entity (Subtype_Mark (S));
20587 -- Explicit subtype declaration case
20589 if Nkind (P) = N_Subtype_Declaration then
20590 Def_Id := Defining_Identifier (P);
20592 -- Explicit derived type definition case
20594 elsif Nkind (P) = N_Derived_Type_Definition then
20595 Def_Id := Defining_Identifier (Parent (P));
20597 -- Implicit case, the Def_Id must be created as an implicit type.
20598 -- The one exception arises in the case of concurrent types, array
20599 -- and access types, where other subsidiary implicit types may be
20600 -- created and must appear before the main implicit type. In these
20601 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
20602 -- has not yet been called to create Def_Id.
20605 if Is_Array_Type (Subtype_Mark_Id)
20606 or else Is_Concurrent_Type (Subtype_Mark_Id)
20607 or else Is_Access_Type (Subtype_Mark_Id)
20611 -- For the other cases, we create a new unattached Itype,
20612 -- and set the indication to ensure it gets attached later.
20616 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20620 -- If the kind of constraint is invalid for this kind of type,
20621 -- then give an error, and then pretend no constraint was given.
20623 if not Is_Valid_Constraint_Kind
20624 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
20627 ("incorrect constraint for this kind of type", Constraint (S));
20629 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
20631 -- Set Ekind of orphan itype, to prevent cascaded errors
20633 if Present (Def_Id) then
20634 Set_Ekind (Def_Id, Ekind (Any_Type));
20637 -- Make recursive call, having got rid of the bogus constraint
20639 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
20642 -- Remaining processing depends on type. Select on Base_Type kind to
20643 -- ensure getting to the concrete type kind in the case of a private
20644 -- subtype (needed when only doing semantic analysis).
20646 case Ekind (Base_Type (Subtype_Mark_Id)) is
20647 when Access_Kind =>
20649 -- If this is a constraint on a class-wide type, discard it.
20650 -- There is currently no way to express a partial discriminant
20651 -- constraint on a type with unknown discriminants. This is
20652 -- a pathology that the ACATS wisely decides not to test.
20654 if Is_Class_Wide_Type (Designated_Type (Subtype_Mark_Id)) then
20655 if Comes_From_Source (S) then
20657 ("constraint on class-wide type ignored??",
20661 if Nkind (P) = N_Subtype_Declaration then
20662 Set_Subtype_Indication (P,
20663 New_Occurrence_Of (Subtype_Mark_Id, Sloc (S)));
20666 return Subtype_Mark_Id;
20669 Constrain_Access (Def_Id, S, Related_Nod);
20672 and then Is_Itype (Designated_Type (Def_Id))
20673 and then Nkind (Related_Nod) = N_Subtype_Declaration
20674 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
20676 Build_Itype_Reference
20677 (Designated_Type (Def_Id), Related_Nod);
20681 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
20683 when Decimal_Fixed_Point_Kind =>
20684 Constrain_Decimal (Def_Id, S);
20686 when Enumeration_Kind =>
20687 Constrain_Enumeration (Def_Id, S);
20688 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20690 when Ordinary_Fixed_Point_Kind =>
20691 Constrain_Ordinary_Fixed (Def_Id, S);
20694 Constrain_Float (Def_Id, S);
20696 when Integer_Kind =>
20697 Constrain_Integer (Def_Id, S);
20698 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20700 when E_Record_Type |
20703 E_Incomplete_Type =>
20704 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20706 if Ekind (Def_Id) = E_Incomplete_Type then
20707 Set_Private_Dependents (Def_Id, New_Elmt_List);
20710 when Private_Kind =>
20711 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20712 Set_Private_Dependents (Def_Id, New_Elmt_List);
20714 -- In case of an invalid constraint prevent further processing
20715 -- since the type constructed is missing expected fields.
20717 if Etype (Def_Id) = Any_Type then
20721 -- If the full view is that of a task with discriminants,
20722 -- we must constrain both the concurrent type and its
20723 -- corresponding record type. Otherwise we will just propagate
20724 -- the constraint to the full view, if available.
20726 if Present (Full_View (Subtype_Mark_Id))
20727 and then Has_Discriminants (Subtype_Mark_Id)
20728 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
20731 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20733 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
20734 Constrain_Concurrent (Full_View_Id, S,
20735 Related_Nod, Related_Id, Suffix);
20736 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
20737 Set_Full_View (Def_Id, Full_View_Id);
20739 -- Introduce an explicit reference to the private subtype,
20740 -- to prevent scope anomalies in gigi if first use appears
20741 -- in a nested context, e.g. a later function body.
20742 -- Should this be generated in other contexts than a full
20743 -- type declaration?
20745 if Is_Itype (Def_Id)
20747 Nkind (Parent (P)) = N_Full_Type_Declaration
20749 Build_Itype_Reference (Def_Id, Parent (P));
20753 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
20756 when Concurrent_Kind =>
20757 Constrain_Concurrent (Def_Id, S,
20758 Related_Nod, Related_Id, Suffix);
20761 Error_Msg_N ("invalid subtype mark in subtype indication", S);
20764 -- Size and Convention are always inherited from the base type
20766 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
20767 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
20771 end Process_Subtype;
20773 --------------------------------------------
20774 -- Propagate_Default_Init_Cond_Attributes --
20775 --------------------------------------------
20777 procedure Propagate_Default_Init_Cond_Attributes
20778 (From_Typ : Entity_Id;
20779 To_Typ : Entity_Id;
20780 Parent_To_Derivation : Boolean := False;
20781 Private_To_Full_View : Boolean := False)
20783 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id);
20784 -- Remove the default initial procedure (if any) from the rep chain of
20787 ----------------------------------------
20788 -- Remove_Default_Init_Cond_Procedure --
20789 ----------------------------------------
20791 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id) is
20792 Found : Boolean := False;
20798 Subp := Subprograms_For_Type (Typ);
20799 while Present (Subp) loop
20800 if Is_Default_Init_Cond_Procedure (Subp) then
20806 Subp := Subprograms_For_Type (Subp);
20810 Set_Subprograms_For_Type (Prev, Subprograms_For_Type (Subp));
20811 Set_Subprograms_For_Type (Subp, Empty);
20813 end Remove_Default_Init_Cond_Procedure;
20817 Inherit_Procedure : Boolean := False;
20819 -- Start of processing for Propagate_Default_Init_Cond_Attributes
20822 if Has_Default_Init_Cond (From_Typ) then
20824 -- A derived type inherits the attributes from its parent type
20826 if Parent_To_Derivation then
20827 Set_Has_Inherited_Default_Init_Cond (To_Typ);
20829 -- A full view shares the attributes with its private view
20832 Set_Has_Default_Init_Cond (To_Typ);
20835 Inherit_Procedure := True;
20837 -- Due to the order of expansion, a derived private type is processed
20838 -- by two routines which both attempt to set the attributes related
20839 -- to pragma Default_Initial_Condition - Build_Derived_Type and then
20840 -- Process_Full_View.
20843 -- type Parent_Typ is private
20844 -- with Default_Initial_Condition ...;
20846 -- type Parent_Typ is ...;
20849 -- with Pack; use Pack;
20850 -- package Pack_2 is
20851 -- type Deriv_Typ is private
20852 -- with Default_Initial_Condition ...;
20854 -- type Deriv_Typ is new Parent_Typ;
20857 -- When Build_Derived_Type operates, it sets the attributes on the
20858 -- full view without taking into account that the private view may
20859 -- define its own default initial condition procedure. This becomes
20860 -- apparent in Process_Full_View which must undo some of the work by
20861 -- Build_Derived_Type and propagate the attributes from the private
20862 -- to the full view.
20864 if Private_To_Full_View then
20865 Set_Has_Inherited_Default_Init_Cond (To_Typ, False);
20866 Remove_Default_Init_Cond_Procedure (To_Typ);
20869 -- A type must inherit the default initial condition procedure from a
20870 -- parent type when the parent itself is inheriting the procedure or
20871 -- when it is defining one. This circuitry is also used when dealing
20872 -- with the private / full view of a type.
20874 elsif Has_Inherited_Default_Init_Cond (From_Typ)
20875 or (Parent_To_Derivation
20876 and Present (Get_Pragma
20877 (From_Typ, Pragma_Default_Initial_Condition)))
20879 Set_Has_Inherited_Default_Init_Cond (To_Typ);
20880 Inherit_Procedure := True;
20883 if Inherit_Procedure
20884 and then No (Default_Init_Cond_Procedure (To_Typ))
20886 Set_Default_Init_Cond_Procedure
20887 (To_Typ, Default_Init_Cond_Procedure (From_Typ));
20889 end Propagate_Default_Init_Cond_Attributes;
20891 -----------------------------
20892 -- Record_Type_Declaration --
20893 -----------------------------
20895 procedure Record_Type_Declaration
20900 Def : constant Node_Id := Type_Definition (N);
20901 Is_Tagged : Boolean;
20902 Tag_Comp : Entity_Id;
20905 -- These flags must be initialized before calling Process_Discriminants
20906 -- because this routine makes use of them.
20908 Set_Ekind (T, E_Record_Type);
20910 Init_Size_Align (T);
20911 Set_Interfaces (T, No_Elist);
20912 Set_Stored_Constraint (T, No_Elist);
20913 Set_Default_SSO (T);
20917 if Ada_Version < Ada_2005 or else not Interface_Present (Def) then
20918 if Limited_Present (Def) then
20919 Check_SPARK_05_Restriction ("limited is not allowed", N);
20922 if Abstract_Present (Def) then
20923 Check_SPARK_05_Restriction ("abstract is not allowed", N);
20926 -- The flag Is_Tagged_Type might have already been set by
20927 -- Find_Type_Name if it detected an error for declaration T. This
20928 -- arises in the case of private tagged types where the full view
20929 -- omits the word tagged.
20932 Tagged_Present (Def)
20933 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
20935 Set_Is_Limited_Record (T, Limited_Present (Def));
20938 Set_Is_Tagged_Type (T, True);
20939 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
20942 -- Type is abstract if full declaration carries keyword, or if
20943 -- previous partial view did.
20945 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
20946 or else Abstract_Present (Def));
20949 Check_SPARK_05_Restriction ("interface is not allowed", N);
20952 Analyze_Interface_Declaration (T, Def);
20954 if Present (Discriminant_Specifications (N)) then
20956 ("interface types cannot have discriminants",
20957 Defining_Identifier
20958 (First (Discriminant_Specifications (N))));
20962 -- First pass: if there are self-referential access components,
20963 -- create the required anonymous access type declarations, and if
20964 -- need be an incomplete type declaration for T itself.
20966 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
20968 if Ada_Version >= Ada_2005
20969 and then Present (Interface_List (Def))
20971 Check_Interfaces (N, Def);
20974 Ifaces_List : Elist_Id;
20977 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
20978 -- already in the parents.
20982 Ifaces_List => Ifaces_List,
20983 Exclude_Parents => True);
20985 Set_Interfaces (T, Ifaces_List);
20989 -- Records constitute a scope for the component declarations within.
20990 -- The scope is created prior to the processing of these declarations.
20991 -- Discriminants are processed first, so that they are visible when
20992 -- processing the other components. The Ekind of the record type itself
20993 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
20995 -- Enter record scope
20999 -- If an incomplete or private type declaration was already given for
21000 -- the type, then this scope already exists, and the discriminants have
21001 -- been declared within. We must verify that the full declaration
21002 -- matches the incomplete one.
21004 Check_Or_Process_Discriminants (N, T, Prev);
21006 Set_Is_Constrained (T, not Has_Discriminants (T));
21007 Set_Has_Delayed_Freeze (T, True);
21009 -- For tagged types add a manually analyzed component corresponding
21010 -- to the component _tag, the corresponding piece of tree will be
21011 -- expanded as part of the freezing actions if it is not a CPP_Class.
21015 -- Do not add the tag unless we are in expansion mode
21017 if Expander_Active then
21018 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
21019 Enter_Name (Tag_Comp);
21021 Set_Ekind (Tag_Comp, E_Component);
21022 Set_Is_Tag (Tag_Comp);
21023 Set_Is_Aliased (Tag_Comp);
21024 Set_Etype (Tag_Comp, RTE (RE_Tag));
21025 Set_DT_Entry_Count (Tag_Comp, No_Uint);
21026 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
21027 Init_Component_Location (Tag_Comp);
21029 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
21030 -- implemented interfaces.
21032 if Has_Interfaces (T) then
21033 Add_Interface_Tag_Components (N, T);
21037 Make_Class_Wide_Type (T);
21038 Set_Direct_Primitive_Operations (T, New_Elmt_List);
21041 -- We must suppress range checks when processing record components in
21042 -- the presence of discriminants, since we don't want spurious checks to
21043 -- be generated during their analysis, but Suppress_Range_Checks flags
21044 -- must be reset the after processing the record definition.
21046 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
21047 -- couldn't we just use the normal range check suppression method here.
21048 -- That would seem cleaner ???
21050 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
21051 Set_Kill_Range_Checks (T, True);
21052 Record_Type_Definition (Def, Prev);
21053 Set_Kill_Range_Checks (T, False);
21055 Record_Type_Definition (Def, Prev);
21058 -- Exit from record scope
21062 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
21063 -- the implemented interfaces and associate them an aliased entity.
21066 and then not Is_Empty_List (Interface_List (Def))
21068 Derive_Progenitor_Subprograms (T, T);
21071 Check_Function_Writable_Actuals (N);
21072 end Record_Type_Declaration;
21074 ----------------------------
21075 -- Record_Type_Definition --
21076 ----------------------------
21078 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
21079 Component : Entity_Id;
21080 Ctrl_Components : Boolean := False;
21081 Final_Storage_Only : Boolean;
21085 if Ekind (Prev_T) = E_Incomplete_Type then
21086 T := Full_View (Prev_T);
21091 -- In SPARK, tagged types and type extensions may only be declared in
21092 -- the specification of library unit packages.
21094 if Present (Def) and then Is_Tagged_Type (T) then
21100 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
21101 Typ := Parent (Def);
21104 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
21105 Typ := Parent (Parent (Def));
21108 Ctxt := Parent (Typ);
21110 if Nkind (Ctxt) = N_Package_Body
21111 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
21113 Check_SPARK_05_Restriction
21114 ("type should be defined in package specification", Typ);
21116 elsif Nkind (Ctxt) /= N_Package_Specification
21117 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
21119 Check_SPARK_05_Restriction
21120 ("type should be defined in library unit package", Typ);
21125 Final_Storage_Only := not Is_Controlled (T);
21127 -- Ada 2005: Check whether an explicit Limited is present in a derived
21128 -- type declaration.
21130 if Nkind (Parent (Def)) = N_Derived_Type_Definition
21131 and then Limited_Present (Parent (Def))
21133 Set_Is_Limited_Record (T);
21136 -- If the component list of a record type is defined by the reserved
21137 -- word null and there is no discriminant part, then the record type has
21138 -- no components and all records of the type are null records (RM 3.7)
21139 -- This procedure is also called to process the extension part of a
21140 -- record extension, in which case the current scope may have inherited
21144 or else No (Component_List (Def))
21145 or else Null_Present (Component_List (Def))
21147 if not Is_Tagged_Type (T) then
21148 Check_SPARK_05_Restriction ("untagged record cannot be null", Def);
21152 Analyze_Declarations (Component_Items (Component_List (Def)));
21154 if Present (Variant_Part (Component_List (Def))) then
21155 Check_SPARK_05_Restriction ("variant part is not allowed", Def);
21156 Analyze (Variant_Part (Component_List (Def)));
21160 -- After completing the semantic analysis of the record definition,
21161 -- record components, both new and inherited, are accessible. Set their
21162 -- kind accordingly. Exclude malformed itypes from illegal declarations,
21163 -- whose Ekind may be void.
21165 Component := First_Entity (Current_Scope);
21166 while Present (Component) loop
21167 if Ekind (Component) = E_Void
21168 and then not Is_Itype (Component)
21170 Set_Ekind (Component, E_Component);
21171 Init_Component_Location (Component);
21174 if Has_Task (Etype (Component)) then
21178 if Has_Protected (Etype (Component)) then
21179 Set_Has_Protected (T);
21182 if Ekind (Component) /= E_Component then
21185 -- Do not set Has_Controlled_Component on a class-wide equivalent
21186 -- type. See Make_CW_Equivalent_Type.
21188 elsif not Is_Class_Wide_Equivalent_Type (T)
21189 and then (Has_Controlled_Component (Etype (Component))
21190 or else (Chars (Component) /= Name_uParent
21191 and then Is_Controlled (Etype (Component))))
21193 Set_Has_Controlled_Component (T, True);
21194 Final_Storage_Only :=
21196 and then Finalize_Storage_Only (Etype (Component));
21197 Ctrl_Components := True;
21200 Next_Entity (Component);
21203 -- A Type is Finalize_Storage_Only only if all its controlled components
21206 if Ctrl_Components then
21207 Set_Finalize_Storage_Only (T, Final_Storage_Only);
21210 -- Place reference to end record on the proper entity, which may
21211 -- be a partial view.
21213 if Present (Def) then
21214 Process_End_Label (Def, 'e', Prev_T);
21216 end Record_Type_Definition;
21218 ------------------------
21219 -- Replace_Components --
21220 ------------------------
21222 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
21223 function Process (N : Node_Id) return Traverse_Result;
21229 function Process (N : Node_Id) return Traverse_Result is
21233 if Nkind (N) = N_Discriminant_Specification then
21234 Comp := First_Discriminant (Typ);
21235 while Present (Comp) loop
21236 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21237 Set_Defining_Identifier (N, Comp);
21241 Next_Discriminant (Comp);
21244 elsif Nkind (N) = N_Component_Declaration then
21245 Comp := First_Component (Typ);
21246 while Present (Comp) loop
21247 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21248 Set_Defining_Identifier (N, Comp);
21252 Next_Component (Comp);
21259 procedure Replace is new Traverse_Proc (Process);
21261 -- Start of processing for Replace_Components
21265 end Replace_Components;
21267 -------------------------------
21268 -- Set_Completion_Referenced --
21269 -------------------------------
21271 procedure Set_Completion_Referenced (E : Entity_Id) is
21273 -- If in main unit, mark entity that is a completion as referenced,
21274 -- warnings go on the partial view when needed.
21276 if In_Extended_Main_Source_Unit (E) then
21277 Set_Referenced (E);
21279 end Set_Completion_Referenced;
21281 ---------------------
21282 -- Set_Default_SSO --
21283 ---------------------
21285 procedure Set_Default_SSO (T : Entity_Id) is
21287 case Opt.Default_SSO is
21291 Set_SSO_Set_Low_By_Default (T, True);
21293 Set_SSO_Set_High_By_Default (T, True);
21295 raise Program_Error;
21297 end Set_Default_SSO;
21299 ---------------------
21300 -- Set_Fixed_Range --
21301 ---------------------
21303 -- The range for fixed-point types is complicated by the fact that we
21304 -- do not know the exact end points at the time of the declaration. This
21305 -- is true for three reasons:
21307 -- A size clause may affect the fudging of the end-points.
21308 -- A small clause may affect the values of the end-points.
21309 -- We try to include the end-points if it does not affect the size.
21311 -- This means that the actual end-points must be established at the
21312 -- point when the type is frozen. Meanwhile, we first narrow the range
21313 -- as permitted (so that it will fit if necessary in a small specified
21314 -- size), and then build a range subtree with these narrowed bounds.
21315 -- Set_Fixed_Range constructs the range from real literal values, and
21316 -- sets the range as the Scalar_Range of the given fixed-point type entity.
21318 -- The parent of this range is set to point to the entity so that it is
21319 -- properly hooked into the tree (unlike normal Scalar_Range entries for
21320 -- other scalar types, which are just pointers to the range in the
21321 -- original tree, this would otherwise be an orphan).
21323 -- The tree is left unanalyzed. When the type is frozen, the processing
21324 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
21325 -- analyzed, and uses this as an indication that it should complete
21326 -- work on the range (it will know the final small and size values).
21328 procedure Set_Fixed_Range
21334 S : constant Node_Id :=
21336 Low_Bound => Make_Real_Literal (Loc, Lo),
21337 High_Bound => Make_Real_Literal (Loc, Hi));
21339 Set_Scalar_Range (E, S);
21342 -- Before the freeze point, the bounds of a fixed point are universal
21343 -- and carry the corresponding type.
21345 Set_Etype (Low_Bound (S), Universal_Real);
21346 Set_Etype (High_Bound (S), Universal_Real);
21347 end Set_Fixed_Range;
21349 ----------------------------------
21350 -- Set_Scalar_Range_For_Subtype --
21351 ----------------------------------
21353 procedure Set_Scalar_Range_For_Subtype
21354 (Def_Id : Entity_Id;
21358 Kind : constant Entity_Kind := Ekind (Def_Id);
21361 -- Defend against previous error
21363 if Nkind (R) = N_Error then
21367 Set_Scalar_Range (Def_Id, R);
21369 -- We need to link the range into the tree before resolving it so
21370 -- that types that are referenced, including importantly the subtype
21371 -- itself, are properly frozen (Freeze_Expression requires that the
21372 -- expression be properly linked into the tree). Of course if it is
21373 -- already linked in, then we do not disturb the current link.
21375 if No (Parent (R)) then
21376 Set_Parent (R, Def_Id);
21379 -- Reset the kind of the subtype during analysis of the range, to
21380 -- catch possible premature use in the bounds themselves.
21382 Set_Ekind (Def_Id, E_Void);
21383 Process_Range_Expr_In_Decl (R, Subt, Subtyp => Def_Id);
21384 Set_Ekind (Def_Id, Kind);
21385 end Set_Scalar_Range_For_Subtype;
21387 --------------------------------------------------------
21388 -- Set_Stored_Constraint_From_Discriminant_Constraint --
21389 --------------------------------------------------------
21391 procedure Set_Stored_Constraint_From_Discriminant_Constraint
21395 -- Make sure set if encountered during Expand_To_Stored_Constraint
21397 Set_Stored_Constraint (E, No_Elist);
21399 -- Give it the right value
21401 if Is_Constrained (E) and then Has_Discriminants (E) then
21402 Set_Stored_Constraint (E,
21403 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
21405 end Set_Stored_Constraint_From_Discriminant_Constraint;
21407 -------------------------------------
21408 -- Signed_Integer_Type_Declaration --
21409 -------------------------------------
21411 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
21412 Implicit_Base : Entity_Id;
21413 Base_Typ : Entity_Id;
21416 Errs : Boolean := False;
21420 function Can_Derive_From (E : Entity_Id) return Boolean;
21421 -- Determine whether given bounds allow derivation from specified type
21423 procedure Check_Bound (Expr : Node_Id);
21424 -- Check bound to make sure it is integral and static. If not, post
21425 -- appropriate error message and set Errs flag
21427 ---------------------
21428 -- Can_Derive_From --
21429 ---------------------
21431 -- Note we check both bounds against both end values, to deal with
21432 -- strange types like ones with a range of 0 .. -12341234.
21434 function Can_Derive_From (E : Entity_Id) return Boolean is
21435 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
21436 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
21438 return Lo <= Lo_Val and then Lo_Val <= Hi
21440 Lo <= Hi_Val and then Hi_Val <= Hi;
21441 end Can_Derive_From;
21447 procedure Check_Bound (Expr : Node_Id) is
21449 -- If a range constraint is used as an integer type definition, each
21450 -- bound of the range must be defined by a static expression of some
21451 -- integer type, but the two bounds need not have the same integer
21452 -- type (Negative bounds are allowed.) (RM 3.5.4)
21454 if not Is_Integer_Type (Etype (Expr)) then
21456 ("integer type definition bounds must be of integer type", Expr);
21459 elsif not Is_OK_Static_Expression (Expr) then
21460 Flag_Non_Static_Expr
21461 ("non-static expression used for integer type bound!", Expr);
21464 -- The bounds are folded into literals, and we set their type to be
21465 -- universal, to avoid typing difficulties: we cannot set the type
21466 -- of the literal to the new type, because this would be a forward
21467 -- reference for the back end, and if the original type is user-
21468 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
21471 if Is_Entity_Name (Expr) then
21472 Fold_Uint (Expr, Expr_Value (Expr), True);
21475 Set_Etype (Expr, Universal_Integer);
21479 -- Start of processing for Signed_Integer_Type_Declaration
21482 -- Create an anonymous base type
21485 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
21487 -- Analyze and check the bounds, they can be of any integer type
21489 Lo := Low_Bound (Def);
21490 Hi := High_Bound (Def);
21492 -- Arbitrarily use Integer as the type if either bound had an error
21494 if Hi = Error or else Lo = Error then
21495 Base_Typ := Any_Integer;
21496 Set_Error_Posted (T, True);
21498 -- Here both bounds are OK expressions
21501 Analyze_And_Resolve (Lo, Any_Integer);
21502 Analyze_And_Resolve (Hi, Any_Integer);
21508 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21509 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21512 -- Find type to derive from
21514 Lo_Val := Expr_Value (Lo);
21515 Hi_Val := Expr_Value (Hi);
21517 if Can_Derive_From (Standard_Short_Short_Integer) then
21518 Base_Typ := Base_Type (Standard_Short_Short_Integer);
21520 elsif Can_Derive_From (Standard_Short_Integer) then
21521 Base_Typ := Base_Type (Standard_Short_Integer);
21523 elsif Can_Derive_From (Standard_Integer) then
21524 Base_Typ := Base_Type (Standard_Integer);
21526 elsif Can_Derive_From (Standard_Long_Integer) then
21527 Base_Typ := Base_Type (Standard_Long_Integer);
21529 elsif Can_Derive_From (Standard_Long_Long_Integer) then
21530 Check_Restriction (No_Long_Long_Integers, Def);
21531 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21534 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21535 Error_Msg_N ("integer type definition bounds out of range", Def);
21536 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21537 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21541 -- Complete both implicit base and declared first subtype entities. The
21542 -- inheritance of the rep item chain ensures that SPARK-related pragmas
21543 -- are not clobbered when the signed integer type acts as a full view of
21546 Set_Etype (Implicit_Base, Base_Typ);
21547 Set_Size_Info (Implicit_Base, Base_Typ);
21548 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
21549 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
21550 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
21552 Set_Ekind (T, E_Signed_Integer_Subtype);
21553 Set_Etype (T, Implicit_Base);
21554 Set_Size_Info (T, Implicit_Base);
21555 Inherit_Rep_Item_Chain (T, Implicit_Base);
21556 Set_Scalar_Range (T, Def);
21557 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
21558 Set_Is_Constrained (T);
21559 end Signed_Integer_Type_Declaration;