1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2014, 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_Pakd; use Exp_Pakd;
39 with Exp_Tss; use Exp_Tss;
40 with Exp_Util; use Exp_Util;
41 with Fname; use Fname;
42 with Freeze; use Freeze;
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 aspects chained on the contract of object Obj_Id as
97 -- if they appeared at the end of the declarative region. The aspects 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 constraint
365 -- Constraints for Typ and a component of Typ, with type Compon_Type,
366 -- create and return the type corresponding to Compon_type where all
367 -- discriminant references are replaced with the corresponding constraint.
368 -- If no discriminant references occur in Compon_Typ then return it as is.
369 -- Constrained_Typ is the final constrained subtype to which the
370 -- constrained Compon_Type belongs. Related_Node is the node where we will
371 -- attach all the itypes created.
373 -- Above description is confused, what is Compon_Type???
375 procedure Constrain_Access
376 (Def_Id : in out Entity_Id;
378 Related_Nod : Node_Id);
379 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
380 -- an anonymous type created for a subtype indication. In that case it is
381 -- created in the procedure and attached to Related_Nod.
383 procedure Constrain_Array
384 (Def_Id : in out Entity_Id;
386 Related_Nod : Node_Id;
387 Related_Id : Entity_Id;
389 -- Apply a list of index constraints to an unconstrained array type. The
390 -- first parameter is the entity for the resulting subtype. A value of
391 -- Empty for Def_Id indicates that an implicit type must be created, but
392 -- creation is delayed (and must be done by this procedure) because other
393 -- subsidiary implicit types must be created first (which is why Def_Id
394 -- is an in/out parameter). The second parameter is a subtype indication
395 -- node for the constrained array to be created (e.g. something of the
396 -- form string (1 .. 10)). Related_Nod gives the place where this type
397 -- has to be inserted in the tree. The Related_Id and Suffix parameters
398 -- are used to build the associated Implicit type name.
400 procedure Constrain_Concurrent
401 (Def_Id : in out Entity_Id;
403 Related_Nod : Node_Id;
404 Related_Id : Entity_Id;
406 -- Apply list of discriminant constraints to an unconstrained concurrent
409 -- SI is the N_Subtype_Indication node containing the constraint and
410 -- the unconstrained type to constrain.
412 -- Def_Id is the entity for the resulting constrained subtype. A value
413 -- of Empty for Def_Id indicates that an implicit type must be created,
414 -- but creation is delayed (and must be done by this procedure) because
415 -- other subsidiary implicit types must be created first (which is why
416 -- Def_Id is an in/out parameter).
418 -- Related_Nod gives the place where this type has to be inserted
421 -- The last two arguments are used to create its external name if needed.
423 function Constrain_Corresponding_Record
424 (Prot_Subt : Entity_Id;
425 Corr_Rec : Entity_Id;
426 Related_Nod : Node_Id;
427 Related_Id : Entity_Id) return Entity_Id;
428 -- When constraining a protected type or task type with discriminants,
429 -- constrain the corresponding record with the same discriminant values.
431 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
432 -- Constrain a decimal fixed point type with a digits constraint and/or a
433 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
435 procedure Constrain_Discriminated_Type
438 Related_Nod : Node_Id;
439 For_Access : Boolean := False);
440 -- Process discriminant constraints of composite type. Verify that values
441 -- have been provided for all discriminants, that the original type is
442 -- unconstrained, and that the types of the supplied expressions match
443 -- the discriminant types. The first three parameters are like in routine
444 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
447 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
448 -- Constrain an enumeration type with a range constraint. This is identical
449 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
451 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
452 -- Constrain a floating point type with either a digits constraint
453 -- and/or a range constraint, building a E_Floating_Point_Subtype.
455 procedure Constrain_Index
458 Related_Nod : Node_Id;
459 Related_Id : Entity_Id;
462 -- Process an index constraint S in a constrained array declaration. The
463 -- constraint can be a subtype name, or a range with or without an explicit
464 -- subtype mark. The index is the corresponding index of the unconstrained
465 -- array. The Related_Id and Suffix parameters are used to build the
466 -- associated Implicit type name.
468 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
469 -- Build subtype of a signed or modular integer type
471 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
472 -- Constrain an ordinary fixed point type with a range constraint, and
473 -- build an E_Ordinary_Fixed_Point_Subtype entity.
475 procedure Copy_And_Swap (Priv, Full : Entity_Id);
476 -- Copy the Priv entity into the entity of its full declaration then swap
477 -- the two entities in such a manner that the former private type is now
478 -- seen as a full type.
480 procedure Decimal_Fixed_Point_Type_Declaration
483 -- Create a new decimal fixed point type, and apply the constraint to
484 -- obtain a subtype of this new type.
486 procedure Complete_Private_Subtype
489 Full_Base : Entity_Id;
490 Related_Nod : Node_Id);
491 -- Complete the implicit full view of a private subtype by setting the
492 -- appropriate semantic fields. If the full view of the parent is a record
493 -- type, build constrained components of subtype.
495 procedure Derive_Progenitor_Subprograms
496 (Parent_Type : Entity_Id;
497 Tagged_Type : Entity_Id);
498 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
499 -- operations of progenitors of Tagged_Type, and replace the subsidiary
500 -- subtypes with Tagged_Type, to build the specs of the inherited interface
501 -- primitives. The derived primitives are aliased to those of the
502 -- interface. This routine takes care also of transferring to the full view
503 -- subprograms associated with the partial view of Tagged_Type that cover
504 -- interface primitives.
506 procedure Derived_Standard_Character
508 Parent_Type : Entity_Id;
509 Derived_Type : Entity_Id);
510 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
511 -- derivations from types Standard.Character and Standard.Wide_Character.
513 procedure Derived_Type_Declaration
516 Is_Completion : Boolean);
517 -- Process a derived type declaration. Build_Derived_Type is invoked
518 -- to process the actual derived type definition. Parameters N and
519 -- Is_Completion have the same meaning as in Build_Derived_Type.
520 -- T is the N_Defining_Identifier for the entity defined in the
521 -- N_Full_Type_Declaration node N, that is T is the derived type.
523 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
524 -- Insert each literal in symbol table, as an overloadable identifier. Each
525 -- enumeration type is mapped into a sequence of integers, and each literal
526 -- is defined as a constant with integer value. If any of the literals are
527 -- character literals, the type is a character type, which means that
528 -- strings are legal aggregates for arrays of components of the type.
530 function Expand_To_Stored_Constraint
532 Constraint : Elist_Id) return Elist_Id;
533 -- Given a constraint (i.e. a list of expressions) on the discriminants of
534 -- Typ, expand it into a constraint on the stored discriminants and return
535 -- the new list of expressions constraining the stored discriminants.
537 function Find_Type_Of_Object
539 Related_Nod : Node_Id) return Entity_Id;
540 -- Get type entity for object referenced by Obj_Def, attaching the
541 -- implicit types generated to Related_Nod
543 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
544 -- Create a new float and apply the constraint to obtain subtype of it
546 function Has_Range_Constraint (N : Node_Id) return Boolean;
547 -- Given an N_Subtype_Indication node N, return True if a range constraint
548 -- is present, either directly, or as part of a digits or delta constraint.
549 -- In addition, a digits constraint in the decimal case returns True, since
550 -- it establishes a default range if no explicit range is present.
552 function Inherit_Components
554 Parent_Base : Entity_Id;
555 Derived_Base : Entity_Id;
557 Inherit_Discr : Boolean;
558 Discs : Elist_Id) return Elist_Id;
559 -- Called from Build_Derived_Record_Type to inherit the components of
560 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
561 -- For more information on derived types and component inheritance please
562 -- consult the comment above the body of Build_Derived_Record_Type.
564 -- N is the original derived type declaration
566 -- Is_Tagged is set if we are dealing with tagged types
568 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
569 -- Parent_Base, otherwise no discriminants are inherited.
571 -- Discs gives the list of constraints that apply to Parent_Base in the
572 -- derived type declaration. If Discs is set to No_Elist, then we have
573 -- the following situation:
575 -- type Parent (D1..Dn : ..) is [tagged] record ...;
576 -- type Derived is new Parent [with ...];
578 -- which gets treated as
580 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
582 -- For untagged types the returned value is an association list. The list
583 -- starts from the association (Parent_Base => Derived_Base), and then it
584 -- contains a sequence of the associations of the form
586 -- (Old_Component => New_Component),
588 -- where Old_Component is the Entity_Id of a component in Parent_Base and
589 -- New_Component is the Entity_Id of the corresponding component in
590 -- Derived_Base. For untagged records, this association list is needed when
591 -- copying the record declaration for the derived base. In the tagged case
592 -- the value returned is irrelevant.
594 function Is_Valid_Constraint_Kind
596 Constraint_Kind : Node_Kind) return Boolean;
597 -- Returns True if it is legal to apply the given kind of constraint to the
598 -- given kind of type (index constraint to an array type, for example).
600 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
601 -- Create new modular type. Verify that modulus is in bounds
603 procedure New_Concatenation_Op (Typ : Entity_Id);
604 -- Create an abbreviated declaration for an operator in order to
605 -- materialize concatenation on array types.
607 procedure Ordinary_Fixed_Point_Type_Declaration
610 -- Create a new ordinary fixed point type, and apply the constraint to
611 -- obtain subtype of it.
613 procedure Prepare_Private_Subtype_Completion
615 Related_Nod : Node_Id);
616 -- Id is a subtype of some private type. Creates the full declaration
617 -- associated with Id whenever possible, i.e. when the full declaration
618 -- of the base type is already known. Records each subtype into
619 -- Private_Dependents of the base type.
621 procedure Process_Incomplete_Dependents
625 -- Process all entities that depend on an incomplete type. There include
626 -- subtypes, subprogram types that mention the incomplete type in their
627 -- profiles, and subprogram with access parameters that designate the
630 -- Inc_T is the defining identifier of an incomplete type declaration, its
631 -- Ekind is E_Incomplete_Type.
633 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
635 -- Full_T is N's defining identifier.
637 -- Subtypes of incomplete types with discriminants are completed when the
638 -- parent type is. This is simpler than private subtypes, because they can
639 -- only appear in the same scope, and there is no need to exchange views.
640 -- Similarly, access_to_subprogram types may have a parameter or a return
641 -- type that is an incomplete type, and that must be replaced with the
644 -- If the full type is tagged, subprogram with access parameters that
645 -- designated the incomplete may be primitive operations of the full type,
646 -- and have to be processed accordingly.
648 procedure Process_Real_Range_Specification (Def : Node_Id);
649 -- Given the type definition for a real type, this procedure processes and
650 -- checks the real range specification of this type definition if one is
651 -- present. If errors are found, error messages are posted, and the
652 -- Real_Range_Specification of Def is reset to Empty.
654 procedure Record_Type_Declaration
658 -- Process a record type declaration (for both untagged and tagged
659 -- records). Parameters T and N are exactly like in procedure
660 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
661 -- for this routine. If this is the completion of an incomplete type
662 -- declaration, Prev is the entity of the incomplete declaration, used for
663 -- cross-referencing. Otherwise Prev = T.
665 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
666 -- This routine is used to process the actual record type definition (both
667 -- for untagged and tagged records). Def is a record type definition node.
668 -- This procedure analyzes the components in this record type definition.
669 -- Prev_T is the entity for the enclosing record type. It is provided so
670 -- that its Has_Task flag can be set if any of the component have Has_Task
671 -- set. If the declaration is the completion of an incomplete type
672 -- declaration, Prev_T is the original incomplete type, whose full view is
675 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
676 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
677 -- build a copy of the declaration tree of the parent, and we create
678 -- independently the list of components for the derived type. Semantic
679 -- information uses the component entities, but record representation
680 -- clauses are validated on the declaration tree. This procedure replaces
681 -- discriminants and components in the declaration with those that have
682 -- been created by Inherit_Components.
684 procedure Set_Fixed_Range
689 -- Build a range node with the given bounds and set it as the Scalar_Range
690 -- of the given fixed-point type entity. Loc is the source location used
691 -- for the constructed range. See body for further details.
693 procedure Set_Scalar_Range_For_Subtype
697 -- This routine is used to set the scalar range field for a subtype given
698 -- Def_Id, the entity for the subtype, and R, the range expression for the
699 -- scalar range. Subt provides the parent subtype to be used to analyze,
700 -- resolve, and check the given range.
702 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
703 -- Create a new signed integer entity, and apply the constraint to obtain
704 -- the required first named subtype of this type.
706 procedure Set_Stored_Constraint_From_Discriminant_Constraint
708 -- E is some record type. This routine computes E's Stored_Constraint
709 -- from its Discriminant_Constraint.
711 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
712 -- Check that an entity in a list of progenitors is an interface,
713 -- emit error otherwise.
715 -----------------------
716 -- Access_Definition --
717 -----------------------
719 function Access_Definition
720 (Related_Nod : Node_Id;
721 N : Node_Id) return Entity_Id
723 Anon_Type : Entity_Id;
724 Anon_Scope : Entity_Id;
725 Desig_Type : Entity_Id;
726 Enclosing_Prot_Type : Entity_Id := Empty;
729 Check_SPARK_Restriction ("access type is not allowed", N);
731 if Is_Entry (Current_Scope)
732 and then Is_Task_Type (Etype (Scope (Current_Scope)))
734 Error_Msg_N ("task entries cannot have access parameters", N);
738 -- Ada 2005: For an object declaration the corresponding anonymous
739 -- type is declared in the current scope.
741 -- If the access definition is the return type of another access to
742 -- function, scope is the current one, because it is the one of the
743 -- current type declaration, except for the pathological case below.
745 if Nkind_In (Related_Nod, N_Object_Declaration,
746 N_Access_Function_Definition)
748 Anon_Scope := Current_Scope;
750 -- A pathological case: function returning access functions that
751 -- return access functions, etc. Each anonymous access type created
752 -- is in the enclosing scope of the outermost function.
759 while Nkind_In (Par, N_Access_Function_Definition,
765 if Nkind (Par) = N_Function_Specification then
766 Anon_Scope := Scope (Defining_Entity (Par));
770 -- For the anonymous function result case, retrieve the scope of the
771 -- function specification's associated entity rather than using the
772 -- current scope. The current scope will be the function itself if the
773 -- formal part is currently being analyzed, but will be the parent scope
774 -- in the case of a parameterless function, and we always want to use
775 -- the function's parent scope. Finally, if the function is a child
776 -- unit, we must traverse the tree to retrieve the proper entity.
778 elsif Nkind (Related_Nod) = N_Function_Specification
779 and then Nkind (Parent (N)) /= N_Parameter_Specification
781 -- If the current scope is a protected type, the anonymous access
782 -- is associated with one of the protected operations, and must
783 -- be available in the scope that encloses the protected declaration.
784 -- Otherwise the type is in the scope enclosing the subprogram.
786 -- If the function has formals, The return type of a subprogram
787 -- declaration is analyzed in the scope of the subprogram (see
788 -- Process_Formals) and thus the protected type, if present, is
789 -- the scope of the current function scope.
791 if Ekind (Current_Scope) = E_Protected_Type then
792 Enclosing_Prot_Type := Current_Scope;
794 elsif Ekind (Current_Scope) = E_Function
795 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
797 Enclosing_Prot_Type := Scope (Current_Scope);
800 if Present (Enclosing_Prot_Type) then
801 Anon_Scope := Scope (Enclosing_Prot_Type);
804 Anon_Scope := Scope (Defining_Entity (Related_Nod));
807 -- For an access type definition, if the current scope is a child
808 -- unit it is the scope of the type.
810 elsif Is_Compilation_Unit (Current_Scope) then
811 Anon_Scope := Current_Scope;
813 -- For access formals, access components, and access discriminants, the
814 -- scope is that of the enclosing declaration,
817 Anon_Scope := Scope (Current_Scope);
822 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
825 and then Ada_Version >= Ada_2005
827 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
830 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
831 -- the corresponding semantic routine
833 if Present (Access_To_Subprogram_Definition (N)) then
835 -- Compiler runtime units are compiled in Ada 2005 mode when building
836 -- the runtime library but must also be compilable in Ada 95 mode
837 -- (when bootstrapping the compiler).
839 Check_Compiler_Unit ("anonymous access to subprogram", N);
841 Access_Subprogram_Declaration
842 (T_Name => Anon_Type,
843 T_Def => Access_To_Subprogram_Definition (N));
845 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
847 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
850 (Anon_Type, E_Anonymous_Access_Subprogram_Type);
853 Set_Can_Use_Internal_Rep
854 (Anon_Type, not Always_Compatible_Rep_On_Target);
856 -- If the anonymous access is associated with a protected operation,
857 -- create a reference to it after the enclosing protected definition
858 -- because the itype will be used in the subsequent bodies.
860 if Ekind (Current_Scope) = E_Protected_Type then
861 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
867 Find_Type (Subtype_Mark (N));
868 Desig_Type := Entity (Subtype_Mark (N));
870 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
871 Set_Etype (Anon_Type, Anon_Type);
873 -- Make sure the anonymous access type has size and alignment fields
874 -- set, as required by gigi. This is necessary in the case of the
875 -- Task_Body_Procedure.
877 if not Has_Private_Component (Desig_Type) then
878 Layout_Type (Anon_Type);
881 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
882 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
883 -- the null value is allowed. In Ada 95 the null value is never allowed.
885 if Ada_Version >= Ada_2005 then
886 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
888 Set_Can_Never_Be_Null (Anon_Type, True);
891 -- The anonymous access type is as public as the discriminated type or
892 -- subprogram that defines it. It is imported (for back-end purposes)
893 -- if the designated type is.
895 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
897 -- Ada 2005 (AI-231): Propagate the access-constant attribute
899 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
901 -- The context is either a subprogram declaration, object declaration,
902 -- or an access discriminant, in a private or a full type declaration.
903 -- In the case of a subprogram, if the designated type is incomplete,
904 -- the operation will be a primitive operation of the full type, to be
905 -- updated subsequently. If the type is imported through a limited_with
906 -- clause, the subprogram is not a primitive operation of the type
907 -- (which is declared elsewhere in some other scope).
909 if Ekind (Desig_Type) = E_Incomplete_Type
910 and then not From_Limited_With (Desig_Type)
911 and then Is_Overloadable (Current_Scope)
913 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
914 Set_Has_Delayed_Freeze (Current_Scope);
917 -- Ada 2005: If the designated type is an interface that may contain
918 -- tasks, create a Master entity for the declaration. This must be done
919 -- before expansion of the full declaration, because the declaration may
920 -- include an expression that is an allocator, whose expansion needs the
921 -- proper Master for the created tasks.
923 if Nkind (Related_Nod) = N_Object_Declaration and then Expander_Active
925 if Is_Interface (Desig_Type) and then Is_Limited_Record (Desig_Type)
927 Build_Class_Wide_Master (Anon_Type);
929 -- Similarly, if the type is an anonymous access that designates
930 -- tasks, create a master entity for it in the current context.
932 elsif Has_Task (Desig_Type) and then Comes_From_Source (Related_Nod)
934 Build_Master_Entity (Defining_Identifier (Related_Nod));
935 Build_Master_Renaming (Anon_Type);
939 -- For a private component of a protected type, it is imperative that
940 -- the back-end elaborate the type immediately after the protected
941 -- declaration, because this type will be used in the declarations
942 -- created for the component within each protected body, so we must
943 -- create an itype reference for it now.
945 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
946 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
948 -- Similarly, if the access definition is the return result of a
949 -- function, create an itype reference for it because it will be used
950 -- within the function body. For a regular function that is not a
951 -- compilation unit, insert reference after the declaration. For a
952 -- protected operation, insert it after the enclosing protected type
953 -- declaration. In either case, do not create a reference for a type
954 -- obtained through a limited_with clause, because this would introduce
955 -- semantic dependencies.
957 -- Similarly, do not create a reference if the designated type is a
958 -- generic formal, because no use of it will reach the backend.
960 elsif Nkind (Related_Nod) = N_Function_Specification
961 and then not From_Limited_With (Desig_Type)
962 and then not Is_Generic_Type (Desig_Type)
964 if Present (Enclosing_Prot_Type) then
965 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
967 elsif Is_List_Member (Parent (Related_Nod))
968 and then Nkind (Parent (N)) /= N_Parameter_Specification
970 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
973 -- Finally, create an itype reference for an object declaration of an
974 -- anonymous access type. This is strictly necessary only for deferred
975 -- constants, but in any case will avoid out-of-scope problems in the
978 elsif Nkind (Related_Nod) = N_Object_Declaration then
979 Build_Itype_Reference (Anon_Type, Related_Nod);
983 end Access_Definition;
985 -----------------------------------
986 -- Access_Subprogram_Declaration --
987 -----------------------------------
989 procedure Access_Subprogram_Declaration
993 procedure Check_For_Premature_Usage (Def : Node_Id);
994 -- Check that type T_Name is not used, directly or recursively, as a
995 -- parameter or a return type in Def. Def is either a subtype, an
996 -- access_definition, or an access_to_subprogram_definition.
998 -------------------------------
999 -- Check_For_Premature_Usage --
1000 -------------------------------
1002 procedure Check_For_Premature_Usage (Def : Node_Id) is
1006 -- Check for a subtype mark
1008 if Nkind (Def) in N_Has_Etype then
1009 if Etype (Def) = T_Name then
1011 ("type& cannot be used before end of its declaration", Def);
1014 -- If this is not a subtype, then this is an access_definition
1016 elsif Nkind (Def) = N_Access_Definition then
1017 if Present (Access_To_Subprogram_Definition (Def)) then
1018 Check_For_Premature_Usage
1019 (Access_To_Subprogram_Definition (Def));
1021 Check_For_Premature_Usage (Subtype_Mark (Def));
1024 -- The only cases left are N_Access_Function_Definition and
1025 -- N_Access_Procedure_Definition.
1028 if Present (Parameter_Specifications (Def)) then
1029 Param := First (Parameter_Specifications (Def));
1030 while Present (Param) loop
1031 Check_For_Premature_Usage (Parameter_Type (Param));
1032 Param := Next (Param);
1036 if Nkind (Def) = N_Access_Function_Definition then
1037 Check_For_Premature_Usage (Result_Definition (Def));
1040 end Check_For_Premature_Usage;
1044 Formals : constant List_Id := Parameter_Specifications (T_Def);
1047 Desig_Type : constant Entity_Id :=
1048 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1050 -- Start of processing for Access_Subprogram_Declaration
1053 Check_SPARK_Restriction ("access type is not allowed", T_Def);
1055 -- Associate the Itype node with the inner full-type declaration or
1056 -- subprogram spec or entry body. This is required to handle nested
1057 -- anonymous declarations. For example:
1060 -- (X : access procedure
1061 -- (Y : access procedure
1064 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1065 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1066 N_Private_Type_Declaration,
1067 N_Private_Extension_Declaration,
1068 N_Procedure_Specification,
1069 N_Function_Specification,
1073 Nkind_In (D_Ityp, N_Object_Declaration,
1074 N_Object_Renaming_Declaration,
1075 N_Formal_Object_Declaration,
1076 N_Formal_Type_Declaration,
1077 N_Task_Type_Declaration,
1078 N_Protected_Type_Declaration))
1080 D_Ityp := Parent (D_Ityp);
1081 pragma Assert (D_Ityp /= Empty);
1084 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1086 if Nkind_In (D_Ityp, N_Procedure_Specification,
1087 N_Function_Specification)
1089 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1091 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1092 N_Object_Declaration,
1093 N_Object_Renaming_Declaration,
1094 N_Formal_Type_Declaration)
1096 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1099 if Nkind (T_Def) = N_Access_Function_Definition then
1100 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1102 Acc : constant Node_Id := Result_Definition (T_Def);
1105 if Present (Access_To_Subprogram_Definition (Acc))
1107 Protected_Present (Access_To_Subprogram_Definition (Acc))
1111 Replace_Anonymous_Access_To_Protected_Subprogram
1117 Access_Definition (T_Def, Result_Definition (T_Def)));
1122 Analyze (Result_Definition (T_Def));
1125 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1128 -- If a null exclusion is imposed on the result type, then
1129 -- create a null-excluding itype (an access subtype) and use
1130 -- it as the function's Etype.
1132 if Is_Access_Type (Typ)
1133 and then Null_Exclusion_In_Return_Present (T_Def)
1135 Set_Etype (Desig_Type,
1136 Create_Null_Excluding_Itype
1138 Related_Nod => T_Def,
1139 Scope_Id => Current_Scope));
1142 if From_Limited_With (Typ) then
1144 -- AI05-151: Incomplete types are allowed in all basic
1145 -- declarations, including access to subprograms.
1147 if Ada_Version >= Ada_2012 then
1152 ("illegal use of incomplete type&",
1153 Result_Definition (T_Def), Typ);
1156 elsif Ekind (Current_Scope) = E_Package
1157 and then In_Private_Part (Current_Scope)
1159 if Ekind (Typ) = E_Incomplete_Type then
1160 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1162 elsif Is_Class_Wide_Type (Typ)
1163 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1166 (Desig_Type, Private_Dependents (Etype (Typ)));
1170 Set_Etype (Desig_Type, Typ);
1175 if not (Is_Type (Etype (Desig_Type))) then
1177 ("expect type in function specification",
1178 Result_Definition (T_Def));
1182 Set_Etype (Desig_Type, Standard_Void_Type);
1185 if Present (Formals) then
1186 Push_Scope (Desig_Type);
1188 -- Some special tests here. These special tests can be removed
1189 -- if and when Itypes always have proper parent pointers to their
1192 -- Special test 1) Link defining_identifier of formals. Required by
1193 -- First_Formal to provide its functionality.
1199 F := First (Formals);
1201 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1202 -- when it is part of an unconstrained type and subtype expansion
1203 -- is disabled. To avoid back-end problems with shared profiles,
1204 -- use previous subprogram type as the designated type, and then
1205 -- remove scope added above.
1207 if ASIS_Mode and then Present (Scope (Defining_Identifier (F)))
1209 Set_Etype (T_Name, T_Name);
1210 Init_Size_Align (T_Name);
1211 Set_Directly_Designated_Type (T_Name,
1212 Scope (Defining_Identifier (F)));
1217 while Present (F) loop
1218 if No (Parent (Defining_Identifier (F))) then
1219 Set_Parent (Defining_Identifier (F), F);
1226 Process_Formals (Formals, Parent (T_Def));
1228 -- Special test 2) End_Scope requires that the parent pointer be set
1229 -- to something reasonable, but Itypes don't have parent pointers. So
1230 -- we set it and then unset it ???
1232 Set_Parent (Desig_Type, T_Name);
1234 Set_Parent (Desig_Type, Empty);
1237 -- Check for premature usage of the type being defined
1239 Check_For_Premature_Usage (T_Def);
1241 -- The return type and/or any parameter type may be incomplete. Mark the
1242 -- subprogram_type as depending on the incomplete type, so that it can
1243 -- be updated when the full type declaration is seen. This only applies
1244 -- to incomplete types declared in some enclosing scope, not to limited
1245 -- views from other packages.
1247 -- Prior to Ada 2012, access to functions can only have in_parameters.
1249 if Present (Formals) then
1250 Formal := First_Formal (Desig_Type);
1251 while Present (Formal) loop
1252 if Ekind (Formal) /= E_In_Parameter
1253 and then Nkind (T_Def) = N_Access_Function_Definition
1254 and then Ada_Version < Ada_2012
1256 Error_Msg_N ("functions can only have IN parameters", Formal);
1259 if Ekind (Etype (Formal)) = E_Incomplete_Type
1260 and then In_Open_Scopes (Scope (Etype (Formal)))
1262 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1263 Set_Has_Delayed_Freeze (Desig_Type);
1266 Next_Formal (Formal);
1270 -- Check whether an indirect call without actuals may be possible. This
1271 -- is used when resolving calls whose result is then indexed.
1273 May_Need_Actuals (Desig_Type);
1275 -- If the return type is incomplete, this is legal as long as the type
1276 -- is declared in the current scope and will be completed in it (rather
1277 -- than being part of limited view).
1279 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1280 and then not Has_Delayed_Freeze (Desig_Type)
1281 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1283 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1284 Set_Has_Delayed_Freeze (Desig_Type);
1287 Check_Delayed_Subprogram (Desig_Type);
1289 if Protected_Present (T_Def) then
1290 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1291 Set_Convention (Desig_Type, Convention_Protected);
1293 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1296 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1298 Set_Etype (T_Name, T_Name);
1299 Init_Size_Align (T_Name);
1300 Set_Directly_Designated_Type (T_Name, Desig_Type);
1302 Generate_Reference_To_Formals (T_Name);
1304 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1306 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1308 Check_Restriction (No_Access_Subprograms, T_Def);
1309 end Access_Subprogram_Declaration;
1311 ----------------------------
1312 -- Access_Type_Declaration --
1313 ----------------------------
1315 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1316 P : constant Node_Id := Parent (Def);
1317 S : constant Node_Id := Subtype_Indication (Def);
1319 Full_Desig : Entity_Id;
1322 Check_SPARK_Restriction ("access type is not allowed", Def);
1324 -- Check for permissible use of incomplete type
1326 if Nkind (S) /= N_Subtype_Indication then
1329 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1330 Set_Directly_Designated_Type (T, Entity (S));
1332 Set_Directly_Designated_Type (T,
1333 Process_Subtype (S, P, T, 'P'));
1337 Set_Directly_Designated_Type (T,
1338 Process_Subtype (S, P, T, 'P'));
1341 if All_Present (Def) or Constant_Present (Def) then
1342 Set_Ekind (T, E_General_Access_Type);
1344 Set_Ekind (T, E_Access_Type);
1347 Full_Desig := Designated_Type (T);
1349 if Base_Type (Full_Desig) = T then
1350 Error_Msg_N ("access type cannot designate itself", S);
1352 -- In Ada 2005, the type may have a limited view through some unit in
1353 -- its own context, allowing the following circularity that cannot be
1356 elsif Is_Class_Wide_Type (Full_Desig) and then Etype (Full_Desig) = T
1359 ("access type cannot designate its own classwide type", S);
1361 -- Clean up indication of tagged status to prevent cascaded errors
1363 Set_Is_Tagged_Type (T, False);
1368 -- If the type has appeared already in a with_type clause, it is frozen
1369 -- and the pointer size is already set. Else, initialize.
1371 if not From_Limited_With (T) then
1372 Init_Size_Align (T);
1375 -- Note that Has_Task is always false, since the access type itself
1376 -- is not a task type. See Einfo for more description on this point.
1377 -- Exactly the same consideration applies to Has_Controlled_Component.
1379 Set_Has_Task (T, False);
1380 Set_Has_Controlled_Component (T, False);
1382 -- Initialize field Finalization_Master explicitly to Empty, to avoid
1383 -- problems where an incomplete view of this entity has been previously
1384 -- established by a limited with and an overlaid version of this field
1385 -- (Stored_Constraint) was initialized for the incomplete view.
1387 -- This reset is performed in most cases except where the access type
1388 -- has been created for the purposes of allocating or deallocating a
1389 -- build-in-place object. Such access types have explicitly set pools
1390 -- and finalization masters.
1392 if No (Associated_Storage_Pool (T)) then
1393 Set_Finalization_Master (T, Empty);
1396 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1399 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1400 Set_Is_Access_Constant (T, Constant_Present (Def));
1401 end Access_Type_Declaration;
1403 ----------------------------------
1404 -- Add_Interface_Tag_Components --
1405 ----------------------------------
1407 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1408 Loc : constant Source_Ptr := Sloc (N);
1412 procedure Add_Tag (Iface : Entity_Id);
1413 -- Add tag for one of the progenitor interfaces
1419 procedure Add_Tag (Iface : Entity_Id) is
1426 pragma Assert (Is_Tagged_Type (Iface) and then Is_Interface (Iface));
1428 -- This is a reasonable place to propagate predicates
1430 if Has_Predicates (Iface) then
1431 Set_Has_Predicates (Typ);
1435 Make_Component_Definition (Loc,
1436 Aliased_Present => True,
1437 Subtype_Indication =>
1438 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1440 Tag := Make_Temporary (Loc, 'V');
1443 Make_Component_Declaration (Loc,
1444 Defining_Identifier => Tag,
1445 Component_Definition => Def);
1447 Analyze_Component_Declaration (Decl);
1449 Set_Analyzed (Decl);
1450 Set_Ekind (Tag, E_Component);
1452 Set_Is_Aliased (Tag);
1453 Set_Related_Type (Tag, Iface);
1454 Init_Component_Location (Tag);
1456 pragma Assert (Is_Frozen (Iface));
1458 Set_DT_Entry_Count (Tag,
1459 DT_Entry_Count (First_Entity (Iface)));
1461 if No (Last_Tag) then
1464 Insert_After (Last_Tag, Decl);
1469 -- If the ancestor has discriminants we need to give special support
1470 -- to store the offset_to_top value of the secondary dispatch tables.
1471 -- For this purpose we add a supplementary component just after the
1472 -- field that contains the tag associated with each secondary DT.
1474 if Typ /= Etype (Typ) and then Has_Discriminants (Etype (Typ)) then
1476 Make_Component_Definition (Loc,
1477 Subtype_Indication =>
1478 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1480 Offset := Make_Temporary (Loc, 'V');
1483 Make_Component_Declaration (Loc,
1484 Defining_Identifier => Offset,
1485 Component_Definition => Def);
1487 Analyze_Component_Declaration (Decl);
1489 Set_Analyzed (Decl);
1490 Set_Ekind (Offset, E_Component);
1491 Set_Is_Aliased (Offset);
1492 Set_Related_Type (Offset, Iface);
1493 Init_Component_Location (Offset);
1494 Insert_After (Last_Tag, Decl);
1505 -- Start of processing for Add_Interface_Tag_Components
1508 if not RTE_Available (RE_Interface_Tag) then
1510 ("(Ada 2005) interface types not supported by this run-time!",
1515 if Ekind (Typ) /= E_Record_Type
1516 or else (Is_Concurrent_Record_Type (Typ)
1517 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1518 or else (not Is_Concurrent_Record_Type (Typ)
1519 and then No (Interfaces (Typ))
1520 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1525 -- Find the current last tag
1527 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1528 Ext := Record_Extension_Part (Type_Definition (N));
1530 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1531 Ext := Type_Definition (N);
1536 if not (Present (Component_List (Ext))) then
1537 Set_Null_Present (Ext, False);
1539 Set_Component_List (Ext,
1540 Make_Component_List (Loc,
1541 Component_Items => L,
1542 Null_Present => False));
1544 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1545 L := Component_Items
1547 (Record_Extension_Part
1548 (Type_Definition (N))));
1550 L := Component_Items
1552 (Type_Definition (N)));
1555 -- Find the last tag component
1558 while Present (Comp) loop
1559 if Nkind (Comp) = N_Component_Declaration
1560 and then Is_Tag (Defining_Identifier (Comp))
1569 -- At this point L references the list of components and Last_Tag
1570 -- references the current last tag (if any). Now we add the tag
1571 -- corresponding with all the interfaces that are not implemented
1574 if Present (Interfaces (Typ)) then
1575 Elmt := First_Elmt (Interfaces (Typ));
1576 while Present (Elmt) loop
1577 Add_Tag (Node (Elmt));
1581 end Add_Interface_Tag_Components;
1583 -------------------------------------
1584 -- Add_Internal_Interface_Entities --
1585 -------------------------------------
1587 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1590 Iface_Elmt : Elmt_Id;
1591 Iface_Prim : Entity_Id;
1592 Ifaces_List : Elist_Id;
1593 New_Subp : Entity_Id := Empty;
1595 Restore_Scope : Boolean := False;
1598 pragma Assert (Ada_Version >= Ada_2005
1599 and then Is_Record_Type (Tagged_Type)
1600 and then Is_Tagged_Type (Tagged_Type)
1601 and then Has_Interfaces (Tagged_Type)
1602 and then not Is_Interface (Tagged_Type));
1604 -- Ensure that the internal entities are added to the scope of the type
1606 if Scope (Tagged_Type) /= Current_Scope then
1607 Push_Scope (Scope (Tagged_Type));
1608 Restore_Scope := True;
1611 Collect_Interfaces (Tagged_Type, Ifaces_List);
1613 Iface_Elmt := First_Elmt (Ifaces_List);
1614 while Present (Iface_Elmt) loop
1615 Iface := Node (Iface_Elmt);
1617 -- Originally we excluded here from this processing interfaces that
1618 -- are parents of Tagged_Type because their primitives are located
1619 -- in the primary dispatch table (and hence no auxiliary internal
1620 -- entities are required to handle secondary dispatch tables in such
1621 -- case). However, these auxiliary entities are also required to
1622 -- handle derivations of interfaces in formals of generics (see
1623 -- Derive_Subprograms).
1625 Elmt := First_Elmt (Primitive_Operations (Iface));
1626 while Present (Elmt) loop
1627 Iface_Prim := Node (Elmt);
1629 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1631 Find_Primitive_Covering_Interface
1632 (Tagged_Type => Tagged_Type,
1633 Iface_Prim => Iface_Prim);
1635 if No (Prim) and then Serious_Errors_Detected > 0 then
1639 pragma Assert (Present (Prim));
1641 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1642 -- differs from the name of the interface primitive then it is
1643 -- a private primitive inherited from a parent type. In such
1644 -- case, given that Tagged_Type covers the interface, the
1645 -- inherited private primitive becomes visible. For such
1646 -- purpose we add a new entity that renames the inherited
1647 -- private primitive.
1649 if Chars (Prim) /= Chars (Iface_Prim) then
1650 pragma Assert (Has_Suffix (Prim, 'P'));
1652 (New_Subp => New_Subp,
1653 Parent_Subp => Iface_Prim,
1654 Derived_Type => Tagged_Type,
1655 Parent_Type => Iface);
1656 Set_Alias (New_Subp, Prim);
1657 Set_Is_Abstract_Subprogram
1658 (New_Subp, Is_Abstract_Subprogram (Prim));
1662 (New_Subp => New_Subp,
1663 Parent_Subp => Iface_Prim,
1664 Derived_Type => Tagged_Type,
1665 Parent_Type => Iface);
1667 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1668 -- associated with interface types. These entities are
1669 -- only registered in the list of primitives of its
1670 -- corresponding tagged type because they are only used
1671 -- to fill the contents of the secondary dispatch tables.
1672 -- Therefore they are removed from the homonym chains.
1674 Set_Is_Hidden (New_Subp);
1675 Set_Is_Internal (New_Subp);
1676 Set_Alias (New_Subp, Prim);
1677 Set_Is_Abstract_Subprogram
1678 (New_Subp, Is_Abstract_Subprogram (Prim));
1679 Set_Interface_Alias (New_Subp, Iface_Prim);
1681 -- If the returned type is an interface then propagate it to
1682 -- the returned type. Needed by the thunk to generate the code
1683 -- which displaces "this" to reference the corresponding
1684 -- secondary dispatch table in the returned object.
1686 if Is_Interface (Etype (Iface_Prim)) then
1687 Set_Etype (New_Subp, Etype (Iface_Prim));
1690 -- Internal entities associated with interface types are
1691 -- only registered in the list of primitives of the tagged
1692 -- type. They are only used to fill the contents of the
1693 -- secondary dispatch tables. Therefore they are not needed
1694 -- in the homonym chains.
1696 Remove_Homonym (New_Subp);
1698 -- Hidden entities associated with interfaces must have set
1699 -- the Has_Delay_Freeze attribute to ensure that, in case of
1700 -- locally defined tagged types (or compiling with static
1701 -- dispatch tables generation disabled) the corresponding
1702 -- entry of the secondary dispatch table is filled when
1703 -- such an entity is frozen.
1705 Set_Has_Delayed_Freeze (New_Subp);
1712 Next_Elmt (Iface_Elmt);
1715 if Restore_Scope then
1718 end Add_Internal_Interface_Entities;
1720 -----------------------------------
1721 -- Analyze_Component_Declaration --
1722 -----------------------------------
1724 procedure Analyze_Component_Declaration (N : Node_Id) is
1725 Id : constant Entity_Id := Defining_Identifier (N);
1726 E : constant Node_Id := Expression (N);
1727 Typ : constant Node_Id :=
1728 Subtype_Indication (Component_Definition (N));
1732 function Contains_POC (Constr : Node_Id) return Boolean;
1733 -- Determines whether a constraint uses the discriminant of a record
1734 -- type thus becoming a per-object constraint (POC).
1736 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1737 -- Typ is the type of the current component, check whether this type is
1738 -- a limited type. Used to validate declaration against that of
1739 -- enclosing record.
1745 function Contains_POC (Constr : Node_Id) return Boolean is
1747 -- Prevent cascaded errors
1749 if Error_Posted (Constr) then
1753 case Nkind (Constr) is
1754 when N_Attribute_Reference =>
1755 return Attribute_Name (Constr) = Name_Access
1756 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1758 when N_Discriminant_Association =>
1759 return Denotes_Discriminant (Expression (Constr));
1761 when N_Identifier =>
1762 return Denotes_Discriminant (Constr);
1764 when N_Index_Or_Discriminant_Constraint =>
1769 IDC := First (Constraints (Constr));
1770 while Present (IDC) loop
1772 -- One per-object constraint is sufficient
1774 if Contains_POC (IDC) then
1785 return Denotes_Discriminant (Low_Bound (Constr))
1787 Denotes_Discriminant (High_Bound (Constr));
1789 when N_Range_Constraint =>
1790 return Denotes_Discriminant (Range_Expression (Constr));
1798 ----------------------
1799 -- Is_Known_Limited --
1800 ----------------------
1802 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1803 P : constant Entity_Id := Etype (Typ);
1804 R : constant Entity_Id := Root_Type (Typ);
1807 if Is_Limited_Record (Typ) then
1810 -- If the root type is limited (and not a limited interface)
1811 -- so is the current type
1813 elsif Is_Limited_Record (R)
1814 and then (not Is_Interface (R) or else not Is_Limited_Interface (R))
1818 -- Else the type may have a limited interface progenitor, but a
1819 -- limited record parent.
1821 elsif R /= P and then Is_Limited_Record (P) then
1827 end Is_Known_Limited;
1829 -- Start of processing for Analyze_Component_Declaration
1832 Generate_Definition (Id);
1835 if Present (Typ) then
1836 T := Find_Type_Of_Object
1837 (Subtype_Indication (Component_Definition (N)), N);
1839 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1840 Check_SPARK_Restriction ("subtype mark required", Typ);
1843 -- Ada 2005 (AI-230): Access Definition case
1846 pragma Assert (Present
1847 (Access_Definition (Component_Definition (N))));
1849 T := Access_Definition
1851 N => Access_Definition (Component_Definition (N)));
1852 Set_Is_Local_Anonymous_Access (T);
1854 -- Ada 2005 (AI-254)
1856 if Present (Access_To_Subprogram_Definition
1857 (Access_Definition (Component_Definition (N))))
1858 and then Protected_Present (Access_To_Subprogram_Definition
1860 (Component_Definition (N))))
1862 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1866 -- If the subtype is a constrained subtype of the enclosing record,
1867 -- (which must have a partial view) the back-end does not properly
1868 -- handle the recursion. Rewrite the component declaration with an
1869 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1870 -- the tree directly because side effects have already been removed from
1871 -- discriminant constraints.
1873 if Ekind (T) = E_Access_Subtype
1874 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1875 and then Comes_From_Source (T)
1876 and then Nkind (Parent (T)) = N_Subtype_Declaration
1877 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1880 (Subtype_Indication (Component_Definition (N)),
1881 New_Copy_Tree (Subtype_Indication (Parent (T))));
1882 T := Find_Type_Of_Object
1883 (Subtype_Indication (Component_Definition (N)), N);
1886 -- If the component declaration includes a default expression, then we
1887 -- check that the component is not of a limited type (RM 3.7(5)),
1888 -- and do the special preanalysis of the expression (see section on
1889 -- "Handling of Default and Per-Object Expressions" in the spec of
1893 Check_SPARK_Restriction ("default expression is not allowed", E);
1894 Preanalyze_Spec_Expression (E, T);
1895 Check_Initialization (T, E);
1897 if Ada_Version >= Ada_2005
1898 and then Ekind (T) = E_Anonymous_Access_Type
1899 and then Etype (E) /= Any_Type
1901 -- Check RM 3.9.2(9): "if the expected type for an expression is
1902 -- an anonymous access-to-specific tagged type, then the object
1903 -- designated by the expression shall not be dynamically tagged
1904 -- unless it is a controlling operand in a call on a dispatching
1907 if Is_Tagged_Type (Directly_Designated_Type (T))
1909 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1911 Ekind (Directly_Designated_Type (Etype (E))) =
1915 ("access to specific tagged type required (RM 3.9.2(9))", E);
1918 -- (Ada 2005: AI-230): Accessibility check for anonymous
1921 if Type_Access_Level (Etype (E)) >
1922 Deepest_Type_Access_Level (T)
1925 ("expression has deeper access level than component " &
1926 "(RM 3.10.2 (12.2))", E);
1929 -- The initialization expression is a reference to an access
1930 -- discriminant. The type of the discriminant is always deeper
1931 -- than any access type.
1933 if Ekind (Etype (E)) = E_Anonymous_Access_Type
1934 and then Is_Entity_Name (E)
1935 and then Ekind (Entity (E)) = E_In_Parameter
1936 and then Present (Discriminal_Link (Entity (E)))
1939 ("discriminant has deeper accessibility level than target",
1945 -- The parent type may be a private view with unknown discriminants,
1946 -- and thus unconstrained. Regular components must be constrained.
1948 if Is_Indefinite_Subtype (T) and then Chars (Id) /= Name_uParent then
1949 if Is_Class_Wide_Type (T) then
1951 ("class-wide subtype with unknown discriminants" &
1952 " in component declaration",
1953 Subtype_Indication (Component_Definition (N)));
1956 ("unconstrained subtype in component declaration",
1957 Subtype_Indication (Component_Definition (N)));
1960 -- Components cannot be abstract, except for the special case of
1961 -- the _Parent field (case of extending an abstract tagged type)
1963 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
1964 Error_Msg_N ("type of a component cannot be abstract", N);
1968 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
1970 -- The component declaration may have a per-object constraint, set
1971 -- the appropriate flag in the defining identifier of the subtype.
1973 if Present (Subtype_Indication (Component_Definition (N))) then
1975 Sindic : constant Node_Id :=
1976 Subtype_Indication (Component_Definition (N));
1978 if Nkind (Sindic) = N_Subtype_Indication
1979 and then Present (Constraint (Sindic))
1980 and then Contains_POC (Constraint (Sindic))
1982 Set_Has_Per_Object_Constraint (Id);
1987 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
1988 -- out some static checks.
1990 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
1991 Null_Exclusion_Static_Checks (N);
1994 -- If this component is private (or depends on a private type), flag the
1995 -- record type to indicate that some operations are not available.
1997 P := Private_Component (T);
2001 -- Check for circular definitions
2003 if P = Any_Type then
2004 Set_Etype (Id, Any_Type);
2006 -- There is a gap in the visibility of operations only if the
2007 -- component type is not defined in the scope of the record type.
2009 elsif Scope (P) = Scope (Current_Scope) then
2012 elsif Is_Limited_Type (P) then
2013 Set_Is_Limited_Composite (Current_Scope);
2016 Set_Is_Private_Composite (Current_Scope);
2021 and then Is_Limited_Type (T)
2022 and then Chars (Id) /= Name_uParent
2023 and then Is_Tagged_Type (Current_Scope)
2025 if Is_Derived_Type (Current_Scope)
2026 and then not Is_Known_Limited (Current_Scope)
2029 ("extension of nonlimited type cannot have limited components",
2032 if Is_Interface (Root_Type (Current_Scope)) then
2034 ("\limitedness is not inherited from limited interface", N);
2035 Error_Msg_N ("\add LIMITED to type indication", N);
2038 Explain_Limited_Type (T, N);
2039 Set_Etype (Id, Any_Type);
2040 Set_Is_Limited_Composite (Current_Scope, False);
2042 elsif not Is_Derived_Type (Current_Scope)
2043 and then not Is_Limited_Record (Current_Scope)
2044 and then not Is_Concurrent_Type (Current_Scope)
2047 ("nonlimited tagged type cannot have limited components", N);
2048 Explain_Limited_Type (T, N);
2049 Set_Etype (Id, Any_Type);
2050 Set_Is_Limited_Composite (Current_Scope, False);
2054 Set_Original_Record_Component (Id, Id);
2056 if Has_Aspects (N) then
2057 Analyze_Aspect_Specifications (N, Id);
2060 Analyze_Dimension (N);
2061 end Analyze_Component_Declaration;
2063 --------------------------
2064 -- Analyze_Declarations --
2065 --------------------------
2067 procedure Analyze_Declarations (L : List_Id) is
2070 procedure Adjust_Decl;
2071 -- Adjust Decl not to include implicit label declarations, since these
2072 -- have strange Sloc values that result in elaboration check problems.
2073 -- (They have the sloc of the label as found in the source, and that
2074 -- is ahead of the current declarative part).
2076 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id);
2077 -- Determine whether Body_Decl denotes the body of a late controlled
2078 -- primitive (either Initialize, Adjust or Finalize). If this is the
2079 -- case, add a proper spec if the body lacks one. The spec is inserted
2080 -- before Body_Decl and immedately analyzed.
2082 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id);
2083 -- Spec_Id is the entity of a package that may define abstract states.
2084 -- If the states have visible refinement, remove the visibility of each
2085 -- constituent at the end of the package body declarations.
2091 procedure Adjust_Decl is
2093 while Present (Prev (Decl))
2094 and then Nkind (Decl) = N_Implicit_Label_Declaration
2100 --------------------------------------
2101 -- Handle_Late_Controlled_Primitive --
2102 --------------------------------------
2104 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id) is
2105 Body_Spec : constant Node_Id := Specification (Body_Decl);
2106 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2107 Loc : constant Source_Ptr := Sloc (Body_Id);
2108 Params : constant List_Id :=
2109 Parameter_Specifications (Body_Spec);
2111 Spec_Id : Entity_Id;
2114 pragma Unreferenced (Dummy);
2115 -- A dummy variable used to capture the unused result of subprogram
2119 -- Consider only procedure bodies whose name matches one of the three
2120 -- controlled primitives.
2122 if Nkind (Body_Spec) /= N_Procedure_Specification
2123 or else not Nam_In (Chars (Body_Id), Name_Adjust,
2129 -- A controlled primitive must have exactly one formal
2131 elsif List_Length (Params) /= 1 then
2135 Dummy := Analyze_Subprogram_Specification (Body_Spec);
2137 -- The type of the formal must be derived from [Limited_]Controlled
2139 if not Is_Controlled (Etype (Defining_Entity (First (Params)))) then
2143 Spec_Id := Find_Corresponding_Spec (Body_Decl, Post_Error => False);
2145 -- The body has a matching spec, therefore it cannot be a late
2148 if Present (Spec_Id) then
2152 -- At this point the body is known to be a late controlled primitive.
2153 -- Generate a matching spec and insert it before the body. Note the
2154 -- use of Copy_Separate_Tree - we want an entirely separate semantic
2155 -- tree in this case.
2157 Spec := Copy_Separate_Tree (Body_Spec);
2159 -- Ensure that the subprogram declaration does not inherit the null
2160 -- indicator from the body as we now have a proper spec/body pair.
2162 Set_Null_Present (Spec, False);
2164 Insert_Before_And_Analyze (Body_Decl,
2165 Make_Subprogram_Declaration (Loc,
2166 Specification => Spec));
2167 end Handle_Late_Controlled_Primitive;
2169 --------------------------------
2170 -- Remove_Visible_Refinements --
2171 --------------------------------
2173 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id) is
2174 State_Elmt : Elmt_Id;
2176 if Present (Abstract_States (Spec_Id)) then
2177 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2178 while Present (State_Elmt) loop
2179 Set_Has_Visible_Refinement (Node (State_Elmt), False);
2180 Next_Elmt (State_Elmt);
2183 end Remove_Visible_Refinements;
2188 Freeze_From : Entity_Id := Empty;
2189 Next_Decl : Node_Id;
2190 Spec_Id : Entity_Id;
2192 Body_Seen : Boolean := False;
2193 -- Flag set when the first body [stub] is encountered
2195 In_Package_Body : Boolean := False;
2196 -- Flag set when the current declaration list belongs to a package body
2198 -- Start of processing for Analyze_Declarations
2201 if Restriction_Check_Required (SPARK_05) then
2202 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2206 while Present (Decl) loop
2208 -- Package spec cannot contain a package declaration in SPARK
2210 if Nkind (Decl) = N_Package_Declaration
2211 and then Nkind (Parent (L)) = N_Package_Specification
2213 Check_SPARK_Restriction
2214 ("package specification cannot contain a package declaration",
2218 -- Complete analysis of declaration
2221 Next_Decl := Next (Decl);
2223 if No (Freeze_From) then
2224 Freeze_From := First_Entity (Current_Scope);
2227 -- At the end of a declarative part, freeze remaining entities
2228 -- declared in it. The end of the visible declarations of package
2229 -- specification is not the end of a declarative part if private
2230 -- declarations are present. The end of a package declaration is a
2231 -- freezing point only if it a library package. A task definition or
2232 -- protected type definition is not a freeze point either. Finally,
2233 -- we do not freeze entities in generic scopes, because there is no
2234 -- code generated for them and freeze nodes will be generated for
2237 -- The end of a package instantiation is not a freeze point, but
2238 -- for now we make it one, because the generic body is inserted
2239 -- (currently) immediately after. Generic instantiations will not
2240 -- be a freeze point once delayed freezing of bodies is implemented.
2241 -- (This is needed in any case for early instantiations ???).
2243 if No (Next_Decl) then
2244 if Nkind_In (Parent (L), N_Component_List,
2246 N_Protected_Definition)
2250 elsif Nkind (Parent (L)) /= N_Package_Specification then
2251 if Nkind (Parent (L)) = N_Package_Body then
2252 Freeze_From := First_Entity (Current_Scope);
2255 -- There may have been several freezing points previously,
2256 -- for example object declarations or subprogram bodies, but
2257 -- at the end of a declarative part we check freezing from
2258 -- the beginning, even though entities may already be frozen,
2259 -- in order to perform visibility checks on delayed aspects.
2262 Freeze_All (First_Entity (Current_Scope), Decl);
2263 Freeze_From := Last_Entity (Current_Scope);
2265 elsif Scope (Current_Scope) /= Standard_Standard
2266 and then not Is_Child_Unit (Current_Scope)
2267 and then No (Generic_Parent (Parent (L)))
2271 elsif L /= Visible_Declarations (Parent (L))
2272 or else No (Private_Declarations (Parent (L)))
2273 or else Is_Empty_List (Private_Declarations (Parent (L)))
2276 Freeze_All (First_Entity (Current_Scope), Decl);
2277 Freeze_From := Last_Entity (Current_Scope);
2280 -- If next node is a body then freeze all types before the body.
2281 -- An exception occurs for some expander-generated bodies. If these
2282 -- are generated at places where in general language rules would not
2283 -- allow a freeze point, then we assume that the expander has
2284 -- explicitly checked that all required types are properly frozen,
2285 -- and we do not cause general freezing here. This special circuit
2286 -- is used when the encountered body is marked as having already
2289 -- In all other cases (bodies that come from source, and expander
2290 -- generated bodies that have not been analyzed yet), freeze all
2291 -- types now. Note that in the latter case, the expander must take
2292 -- care to attach the bodies at a proper place in the tree so as to
2293 -- not cause unwanted freezing at that point.
2295 elsif not Analyzed (Next_Decl) and then Is_Body (Next_Decl) then
2297 -- When a controlled type is frozen, the expander generates stream
2298 -- and controlled type support routines. If the freeze is caused
2299 -- by the stand alone body of Initialize, Adjust and Finalize, the
2300 -- expander will end up using the wrong version of these routines
2301 -- as the body has not been processed yet. To remedy this, detect
2302 -- a late controlled primitive and create a proper spec for it.
2303 -- This ensures that the primitive will override its inherited
2304 -- counterpart before the freeze takes place.
2306 -- If the declaration we just processed is a body, do not attempt
2307 -- to examine Next_Decl as the late primitive idiom can only apply
2308 -- to the first encountered body.
2310 -- The spec of the late primitive is not generated in ASIS mode to
2311 -- ensure a consistent list of primitives that indicates the true
2312 -- semantic structure of the program (which is not relevant when
2313 -- generating executable code.
2315 -- ??? a cleaner approach may be possible and/or this solution
2316 -- could be extended to general-purpose late primitives, TBD.
2318 if not ASIS_Mode and then not Body_Seen and then not Is_Body (Decl)
2322 if Nkind (Next_Decl) = N_Subprogram_Body then
2323 Handle_Late_Controlled_Primitive (Next_Decl);
2328 Freeze_All (Freeze_From, Decl);
2329 Freeze_From := Last_Entity (Current_Scope);
2335 -- Analyze the contracts of packages and their bodies
2338 Context := Parent (L);
2340 if Nkind (Context) = N_Package_Specification then
2342 -- When a package has private declarations, its contract must be
2343 -- analyzed at the end of the said declarations. This way both the
2344 -- analysis and freeze actions are properly synchronized in case
2345 -- of private type use within the contract.
2347 if L = Private_Declarations (Context) then
2348 Analyze_Package_Contract (Defining_Entity (Context));
2350 -- Otherwise the contract is analyzed at the end of the visible
2353 elsif L = Visible_Declarations (Context)
2354 and then No (Private_Declarations (Context))
2356 Analyze_Package_Contract (Defining_Entity (Context));
2359 elsif Nkind (Context) = N_Package_Body then
2360 In_Package_Body := True;
2361 Spec_Id := Corresponding_Spec (Context);
2363 Analyze_Package_Body_Contract (Defining_Entity (Context));
2367 -- Analyze the contracts of subprogram declarations, subprogram bodies
2368 -- and variables now due to the delayed visibility requirements of their
2372 while Present (Decl) loop
2373 if Nkind (Decl) = N_Object_Declaration then
2374 Analyze_Object_Contract (Defining_Entity (Decl));
2376 elsif Nkind_In (Decl, N_Abstract_Subprogram_Declaration,
2377 N_Subprogram_Declaration)
2379 Analyze_Subprogram_Contract (Defining_Entity (Decl));
2381 elsif Nkind (Decl) = N_Subprogram_Body then
2382 Analyze_Subprogram_Body_Contract (Defining_Entity (Decl));
2384 elsif Nkind (Decl) = N_Subprogram_Body_Stub then
2385 Analyze_Subprogram_Body_Stub_Contract (Defining_Entity (Decl));
2391 -- State refinements are visible upto the end the of the package body
2392 -- declarations. Hide the refinements from visibility to restore the
2393 -- original state conditions.
2395 if In_Package_Body then
2396 Remove_Visible_Refinements (Spec_Id);
2398 end Analyze_Declarations;
2400 -----------------------------------
2401 -- Analyze_Full_Type_Declaration --
2402 -----------------------------------
2404 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2405 Def : constant Node_Id := Type_Definition (N);
2406 Def_Id : constant Entity_Id := Defining_Identifier (N);
2410 Is_Remote : constant Boolean :=
2411 (Is_Remote_Types (Current_Scope)
2412 or else Is_Remote_Call_Interface (Current_Scope))
2413 and then not (In_Private_Part (Current_Scope)
2414 or else In_Package_Body (Current_Scope));
2416 procedure Check_Ops_From_Incomplete_Type;
2417 -- If there is a tagged incomplete partial view of the type, traverse
2418 -- the primitives of the incomplete view and change the type of any
2419 -- controlling formals and result to indicate the full view. The
2420 -- primitives will be added to the full type's primitive operations
2421 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2422 -- is called from Process_Incomplete_Dependents).
2424 ------------------------------------
2425 -- Check_Ops_From_Incomplete_Type --
2426 ------------------------------------
2428 procedure Check_Ops_From_Incomplete_Type is
2435 and then Ekind (Prev) = E_Incomplete_Type
2436 and then Is_Tagged_Type (Prev)
2437 and then Is_Tagged_Type (T)
2439 Elmt := First_Elmt (Primitive_Operations (Prev));
2440 while Present (Elmt) loop
2443 Formal := First_Formal (Op);
2444 while Present (Formal) loop
2445 if Etype (Formal) = Prev then
2446 Set_Etype (Formal, T);
2449 Next_Formal (Formal);
2452 if Etype (Op) = Prev then
2459 end Check_Ops_From_Incomplete_Type;
2461 -- Start of processing for Analyze_Full_Type_Declaration
2464 Prev := Find_Type_Name (N);
2466 -- The full view, if present, now points to the current type
2468 -- Ada 2005 (AI-50217): If the type was previously decorated when
2469 -- imported through a LIMITED WITH clause, it appears as incomplete
2470 -- but has no full view.
2472 if Ekind (Prev) = E_Incomplete_Type and then Present (Full_View (Prev))
2474 T := Full_View (Prev);
2479 Set_Is_Pure (T, Is_Pure (Current_Scope));
2481 -- We set the flag Is_First_Subtype here. It is needed to set the
2482 -- corresponding flag for the Implicit class-wide-type created
2483 -- during tagged types processing.
2485 Set_Is_First_Subtype (T, True);
2487 -- Only composite types other than array types are allowed to have
2492 -- For derived types, the rule will be checked once we've figured
2493 -- out the parent type.
2495 when N_Derived_Type_Definition =>
2498 -- For record types, discriminants are allowed, unless we are in
2501 when N_Record_Definition =>
2502 if Present (Discriminant_Specifications (N)) then
2503 Check_SPARK_Restriction
2504 ("discriminant type is not allowed",
2506 (First (Discriminant_Specifications (N))));
2510 if Present (Discriminant_Specifications (N)) then
2512 ("elementary or array type cannot have discriminants",
2514 (First (Discriminant_Specifications (N))));
2518 -- Elaborate the type definition according to kind, and generate
2519 -- subsidiary (implicit) subtypes where needed. We skip this if it was
2520 -- already done (this happens during the reanalysis that follows a call
2521 -- to the high level optimizer).
2523 if not Analyzed (T) then
2528 when N_Access_To_Subprogram_Definition =>
2529 Access_Subprogram_Declaration (T, Def);
2531 -- If this is a remote access to subprogram, we must create the
2532 -- equivalent fat pointer type, and related subprograms.
2535 Process_Remote_AST_Declaration (N);
2538 -- Validate categorization rule against access type declaration
2539 -- usually a violation in Pure unit, Shared_Passive unit.
2541 Validate_Access_Type_Declaration (T, N);
2543 when N_Access_To_Object_Definition =>
2544 Access_Type_Declaration (T, Def);
2546 -- Validate categorization rule against access type declaration
2547 -- usually a violation in Pure unit, Shared_Passive unit.
2549 Validate_Access_Type_Declaration (T, N);
2551 -- If we are in a Remote_Call_Interface package and define a
2552 -- RACW, then calling stubs and specific stream attributes
2556 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
2558 Add_RACW_Features (Def_Id);
2561 -- Set no strict aliasing flag if config pragma seen
2563 if Opt.No_Strict_Aliasing then
2564 Set_No_Strict_Aliasing (Base_Type (Def_Id));
2567 when N_Array_Type_Definition =>
2568 Array_Type_Declaration (T, Def);
2570 when N_Derived_Type_Definition =>
2571 Derived_Type_Declaration (T, N, T /= Def_Id);
2573 when N_Enumeration_Type_Definition =>
2574 Enumeration_Type_Declaration (T, Def);
2576 when N_Floating_Point_Definition =>
2577 Floating_Point_Type_Declaration (T, Def);
2579 when N_Decimal_Fixed_Point_Definition =>
2580 Decimal_Fixed_Point_Type_Declaration (T, Def);
2582 when N_Ordinary_Fixed_Point_Definition =>
2583 Ordinary_Fixed_Point_Type_Declaration (T, Def);
2585 when N_Signed_Integer_Type_Definition =>
2586 Signed_Integer_Type_Declaration (T, Def);
2588 when N_Modular_Type_Definition =>
2589 Modular_Type_Declaration (T, Def);
2591 when N_Record_Definition =>
2592 Record_Type_Declaration (T, N, Prev);
2594 -- If declaration has a parse error, nothing to elaborate.
2600 raise Program_Error;
2605 if Etype (T) = Any_Type then
2609 -- Controlled type is not allowed in SPARK
2611 if Is_Visibly_Controlled (T) then
2612 Check_SPARK_Restriction ("controlled type is not allowed", N);
2615 -- Some common processing for all types
2617 Set_Depends_On_Private (T, Has_Private_Component (T));
2618 Check_Ops_From_Incomplete_Type;
2620 -- Both the declared entity, and its anonymous base type if one
2621 -- was created, need freeze nodes allocated.
2624 B : constant Entity_Id := Base_Type (T);
2627 -- In the case where the base type differs from the first subtype, we
2628 -- pre-allocate a freeze node, and set the proper link to the first
2629 -- subtype. Freeze_Entity will use this preallocated freeze node when
2630 -- it freezes the entity.
2632 -- This does not apply if the base type is a generic type, whose
2633 -- declaration is independent of the current derived definition.
2635 if B /= T and then not Is_Generic_Type (B) then
2636 Ensure_Freeze_Node (B);
2637 Set_First_Subtype_Link (Freeze_Node (B), T);
2640 -- A type that is imported through a limited_with clause cannot
2641 -- generate any code, and thus need not be frozen. However, an access
2642 -- type with an imported designated type needs a finalization list,
2643 -- which may be referenced in some other package that has non-limited
2644 -- visibility on the designated type. Thus we must create the
2645 -- finalization list at the point the access type is frozen, to
2646 -- prevent unsatisfied references at link time.
2648 if not From_Limited_With (T) or else Is_Access_Type (T) then
2649 Set_Has_Delayed_Freeze (T);
2653 -- Case where T is the full declaration of some private type which has
2654 -- been swapped in Defining_Identifier (N).
2656 if T /= Def_Id and then Is_Private_Type (Def_Id) then
2657 Process_Full_View (N, T, Def_Id);
2659 -- Record the reference. The form of this is a little strange, since
2660 -- the full declaration has been swapped in. So the first parameter
2661 -- here represents the entity to which a reference is made which is
2662 -- the "real" entity, i.e. the one swapped in, and the second
2663 -- parameter provides the reference location.
2665 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
2666 -- since we don't want a complaint about the full type being an
2667 -- unwanted reference to the private type
2670 B : constant Boolean := Has_Pragma_Unreferenced (T);
2672 Set_Has_Pragma_Unreferenced (T, False);
2673 Generate_Reference (T, T, 'c');
2674 Set_Has_Pragma_Unreferenced (T, B);
2677 Set_Completion_Referenced (Def_Id);
2679 -- For completion of incomplete type, process incomplete dependents
2680 -- and always mark the full type as referenced (it is the incomplete
2681 -- type that we get for any real reference).
2683 elsif Ekind (Prev) = E_Incomplete_Type then
2684 Process_Incomplete_Dependents (N, T, Prev);
2685 Generate_Reference (Prev, Def_Id, 'c');
2686 Set_Completion_Referenced (Def_Id);
2688 -- If not private type or incomplete type completion, this is a real
2689 -- definition of a new entity, so record it.
2692 Generate_Definition (Def_Id);
2695 if Chars (Scope (Def_Id)) = Name_System
2696 and then Chars (Def_Id) = Name_Address
2697 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
2699 Set_Is_Descendent_Of_Address (Def_Id);
2700 Set_Is_Descendent_Of_Address (Base_Type (Def_Id));
2701 Set_Is_Descendent_Of_Address (Prev);
2704 Set_Optimize_Alignment_Flags (Def_Id);
2705 Check_Eliminated (Def_Id);
2707 -- If the declaration is a completion and aspects are present, apply
2708 -- them to the entity for the type which is currently the partial
2709 -- view, but which is the one that will be frozen.
2711 if Has_Aspects (N) then
2712 if Prev /= Def_Id then
2713 Analyze_Aspect_Specifications (N, Prev);
2715 Analyze_Aspect_Specifications (N, Def_Id);
2718 end Analyze_Full_Type_Declaration;
2720 ----------------------------------
2721 -- Analyze_Incomplete_Type_Decl --
2722 ----------------------------------
2724 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
2725 F : constant Boolean := Is_Pure (Current_Scope);
2729 Check_SPARK_Restriction ("incomplete type is not allowed", N);
2731 Generate_Definition (Defining_Identifier (N));
2733 -- Process an incomplete declaration. The identifier must not have been
2734 -- declared already in the scope. However, an incomplete declaration may
2735 -- appear in the private part of a package, for a private type that has
2736 -- already been declared.
2738 -- In this case, the discriminants (if any) must match
2740 T := Find_Type_Name (N);
2742 Set_Ekind (T, E_Incomplete_Type);
2743 Init_Size_Align (T);
2744 Set_Is_First_Subtype (T, True);
2747 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
2748 -- incomplete types.
2750 if Tagged_Present (N) then
2751 Set_Is_Tagged_Type (T);
2752 Make_Class_Wide_Type (T);
2753 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2758 Set_Stored_Constraint (T, No_Elist);
2760 if Present (Discriminant_Specifications (N)) then
2761 Process_Discriminants (N);
2766 -- If the type has discriminants, non-trivial subtypes may be
2767 -- declared before the full view of the type. The full views of those
2768 -- subtypes will be built after the full view of the type.
2770 Set_Private_Dependents (T, New_Elmt_List);
2772 end Analyze_Incomplete_Type_Decl;
2774 -----------------------------------
2775 -- Analyze_Interface_Declaration --
2776 -----------------------------------
2778 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
2779 CW : constant Entity_Id := Class_Wide_Type (T);
2782 Set_Is_Tagged_Type (T);
2784 Set_Is_Limited_Record (T, Limited_Present (Def)
2785 or else Task_Present (Def)
2786 or else Protected_Present (Def)
2787 or else Synchronized_Present (Def));
2789 -- Type is abstract if full declaration carries keyword, or if previous
2790 -- partial view did.
2792 Set_Is_Abstract_Type (T);
2793 Set_Is_Interface (T);
2795 -- Type is a limited interface if it includes the keyword limited, task,
2796 -- protected, or synchronized.
2798 Set_Is_Limited_Interface
2799 (T, Limited_Present (Def)
2800 or else Protected_Present (Def)
2801 or else Synchronized_Present (Def)
2802 or else Task_Present (Def));
2804 Set_Interfaces (T, New_Elmt_List);
2805 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2807 -- Complete the decoration of the class-wide entity if it was already
2808 -- built (i.e. during the creation of the limited view)
2810 if Present (CW) then
2811 Set_Is_Interface (CW);
2812 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
2815 -- Check runtime support for synchronized interfaces
2817 if VM_Target = No_VM
2818 and then (Is_Task_Interface (T)
2819 or else Is_Protected_Interface (T)
2820 or else Is_Synchronized_Interface (T))
2821 and then not RTE_Available (RE_Select_Specific_Data)
2823 Error_Msg_CRT ("synchronized interfaces", T);
2825 end Analyze_Interface_Declaration;
2827 -----------------------------
2828 -- Analyze_Itype_Reference --
2829 -----------------------------
2831 -- Nothing to do. This node is placed in the tree only for the benefit of
2832 -- back end processing, and has no effect on the semantic processing.
2834 procedure Analyze_Itype_Reference (N : Node_Id) is
2836 pragma Assert (Is_Itype (Itype (N)));
2838 end Analyze_Itype_Reference;
2840 --------------------------------
2841 -- Analyze_Number_Declaration --
2842 --------------------------------
2844 procedure Analyze_Number_Declaration (N : Node_Id) is
2845 Id : constant Entity_Id := Defining_Identifier (N);
2846 E : constant Node_Id := Expression (N);
2848 Index : Interp_Index;
2852 Generate_Definition (Id);
2855 -- This is an optimization of a common case of an integer literal
2857 if Nkind (E) = N_Integer_Literal then
2858 Set_Is_Static_Expression (E, True);
2859 Set_Etype (E, Universal_Integer);
2861 Set_Etype (Id, Universal_Integer);
2862 Set_Ekind (Id, E_Named_Integer);
2863 Set_Is_Frozen (Id, True);
2867 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2869 -- Process expression, replacing error by integer zero, to avoid
2870 -- cascaded errors or aborts further along in the processing
2872 -- Replace Error by integer zero, which seems least likely to cause
2876 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
2877 Set_Error_Posted (E);
2882 -- Verify that the expression is static and numeric. If
2883 -- the expression is overloaded, we apply the preference
2884 -- rule that favors root numeric types.
2886 if not Is_Overloaded (E) then
2892 Get_First_Interp (E, Index, It);
2893 while Present (It.Typ) loop
2894 if (Is_Integer_Type (It.Typ) or else Is_Real_Type (It.Typ))
2895 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
2897 if T = Any_Type then
2900 elsif It.Typ = Universal_Real
2901 or else It.Typ = Universal_Integer
2903 -- Choose universal interpretation over any other
2910 Get_Next_Interp (Index, It);
2914 if Is_Integer_Type (T) then
2916 Set_Etype (Id, Universal_Integer);
2917 Set_Ekind (Id, E_Named_Integer);
2919 elsif Is_Real_Type (T) then
2921 -- Because the real value is converted to universal_real, this is a
2922 -- legal context for a universal fixed expression.
2924 if T = Universal_Fixed then
2926 Loc : constant Source_Ptr := Sloc (N);
2927 Conv : constant Node_Id := Make_Type_Conversion (Loc,
2929 New_Occurrence_Of (Universal_Real, Loc),
2930 Expression => Relocate_Node (E));
2937 elsif T = Any_Fixed then
2938 Error_Msg_N ("illegal context for mixed mode operation", E);
2940 -- Expression is of the form : universal_fixed * integer. Try to
2941 -- resolve as universal_real.
2943 T := Universal_Real;
2948 Set_Etype (Id, Universal_Real);
2949 Set_Ekind (Id, E_Named_Real);
2952 Wrong_Type (E, Any_Numeric);
2956 Set_Ekind (Id, E_Constant);
2957 Set_Never_Set_In_Source (Id, True);
2958 Set_Is_True_Constant (Id, True);
2962 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
2963 Set_Etype (E, Etype (Id));
2966 if not Is_OK_Static_Expression (E) then
2967 Flag_Non_Static_Expr
2968 ("non-static expression used in number declaration!", E);
2969 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
2970 Set_Etype (E, Any_Type);
2972 end Analyze_Number_Declaration;
2974 -----------------------------
2975 -- Analyze_Object_Contract --
2976 -----------------------------
2978 procedure Analyze_Object_Contract (Obj_Id : Entity_Id) is
2979 Obj_Typ : constant Entity_Id := Etype (Obj_Id);
2980 AR_Val : Boolean := False;
2981 AW_Val : Boolean := False;
2982 ER_Val : Boolean := False;
2983 EW_Val : Boolean := False;
2985 Seen : Boolean := False;
2988 if Ekind (Obj_Id) = E_Constant then
2990 -- A constant cannot be volatile. This check is only relevant when
2991 -- SPARK_Mode is on as it is not standard Ada legality rule. Do not
2992 -- flag internally-generated constants that map generic formals to
2993 -- actuals in instantiations (SPARK RM 7.1.3(6)).
2996 and then Is_SPARK_Volatile (Obj_Id)
2997 and then No (Corresponding_Generic_Association (Parent (Obj_Id)))
2999 Error_Msg_N ("constant cannot be volatile", Obj_Id);
3002 else pragma Assert (Ekind (Obj_Id) = E_Variable);
3004 -- The following checks are only relevant when SPARK_Mode is on as
3005 -- they are not standard Ada legality rules.
3007 if SPARK_Mode = On then
3008 if Is_SPARK_Volatile (Obj_Id) then
3010 -- The declaration of a volatile object must appear at the
3011 -- library level (SPARK RM 7.1.3(7), C.6(6)).
3013 if not Is_Library_Level_Entity (Obj_Id) then
3015 ("volatile variable & must be declared at library level",
3018 -- An object of a discriminated type cannot be volatile
3019 -- (SPARK RM C.6(4)).
3021 elsif Has_Discriminants (Obj_Typ) then
3023 ("discriminated object & cannot be volatile", Obj_Id);
3025 -- An object of a tagged type cannot be volatile
3026 -- (SPARK RM C.6(5)).
3028 elsif Is_Tagged_Type (Obj_Typ) then
3029 Error_Msg_N ("tagged object & cannot be volatile", Obj_Id);
3032 -- The object is not volatile
3035 -- A non-volatile object cannot have volatile components
3036 -- (SPARK RM 7.1.3(7)).
3038 if not Is_SPARK_Volatile (Obj_Id)
3039 and then Has_Volatile_Component (Obj_Typ)
3042 ("non-volatile object & cannot have volatile components",
3048 -- Analyze all external properties
3050 Prag := Get_Pragma (Obj_Id, Pragma_Async_Readers);
3052 if Present (Prag) then
3053 Analyze_External_Property_In_Decl_Part (Prag, AR_Val);
3057 Prag := Get_Pragma (Obj_Id, Pragma_Async_Writers);
3059 if Present (Prag) then
3060 Analyze_External_Property_In_Decl_Part (Prag, AW_Val);
3064 Prag := Get_Pragma (Obj_Id, Pragma_Effective_Reads);
3066 if Present (Prag) then
3067 Analyze_External_Property_In_Decl_Part (Prag, ER_Val);
3071 Prag := Get_Pragma (Obj_Id, Pragma_Effective_Writes);
3073 if Present (Prag) then
3074 Analyze_External_Property_In_Decl_Part (Prag, EW_Val);
3078 -- Verify the mutual interaction of the various external properties
3081 Check_External_Properties (Obj_Id, AR_Val, AW_Val, ER_Val, EW_Val);
3084 -- Check whether the lack of indicator Part_Of agrees with the
3085 -- placement of the variable with respect to the state space.
3087 Prag := Get_Pragma (Obj_Id, Pragma_Part_Of);
3090 Check_Missing_Part_Of (Obj_Id);
3093 end Analyze_Object_Contract;
3095 --------------------------------
3096 -- Analyze_Object_Declaration --
3097 --------------------------------
3099 procedure Analyze_Object_Declaration (N : Node_Id) is
3100 Loc : constant Source_Ptr := Sloc (N);
3101 Id : constant Entity_Id := Defining_Identifier (N);
3105 E : Node_Id := Expression (N);
3106 -- E is set to Expression (N) throughout this routine. When
3107 -- Expression (N) is modified, E is changed accordingly.
3109 Prev_Entity : Entity_Id := Empty;
3111 function Count_Tasks (T : Entity_Id) return Uint;
3112 -- This function is called when a non-generic library level object of a
3113 -- task type is declared. Its function is to count the static number of
3114 -- tasks declared within the type (it is only called if Has_Tasks is set
3115 -- for T). As a side effect, if an array of tasks with non-static bounds
3116 -- or a variant record type is encountered, Check_Restrictions is called
3117 -- indicating the count is unknown.
3123 function Count_Tasks (T : Entity_Id) return Uint is
3129 if Is_Task_Type (T) then
3132 elsif Is_Record_Type (T) then
3133 if Has_Discriminants (T) then
3134 Check_Restriction (Max_Tasks, N);
3139 C := First_Component (T);
3140 while Present (C) loop
3141 V := V + Count_Tasks (Etype (C));
3148 elsif Is_Array_Type (T) then
3149 X := First_Index (T);
3150 V := Count_Tasks (Component_Type (T));
3151 while Present (X) loop
3154 if not Is_Static_Subtype (C) then
3155 Check_Restriction (Max_Tasks, N);
3158 V := V * (UI_Max (Uint_0,
3159 Expr_Value (Type_High_Bound (C)) -
3160 Expr_Value (Type_Low_Bound (C)) + Uint_1));
3173 -- Start of processing for Analyze_Object_Declaration
3176 -- There are three kinds of implicit types generated by an
3177 -- object declaration:
3179 -- 1. Those generated by the original Object Definition
3181 -- 2. Those generated by the Expression
3183 -- 3. Those used to constrain the Object Definition with the
3184 -- expression constraints when the definition is unconstrained.
3186 -- They must be generated in this order to avoid order of elaboration
3187 -- issues. Thus the first step (after entering the name) is to analyze
3188 -- the object definition.
3190 if Constant_Present (N) then
3191 Prev_Entity := Current_Entity_In_Scope (Id);
3193 if Present (Prev_Entity)
3195 -- If the homograph is an implicit subprogram, it is overridden
3196 -- by the current declaration.
3198 ((Is_Overloadable (Prev_Entity)
3199 and then Is_Inherited_Operation (Prev_Entity))
3201 -- The current object is a discriminal generated for an entry
3202 -- family index. Even though the index is a constant, in this
3203 -- particular context there is no true constant redeclaration.
3204 -- Enter_Name will handle the visibility.
3207 (Is_Discriminal (Id)
3208 and then Ekind (Discriminal_Link (Id)) =
3209 E_Entry_Index_Parameter)
3211 -- The current object is the renaming for a generic declared
3212 -- within the instance.
3215 (Ekind (Prev_Entity) = E_Package
3216 and then Nkind (Parent (Prev_Entity)) =
3217 N_Package_Renaming_Declaration
3218 and then not Comes_From_Source (Prev_Entity)
3219 and then Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
3221 Prev_Entity := Empty;
3225 if Present (Prev_Entity) then
3226 Constant_Redeclaration (Id, N, T);
3228 Generate_Reference (Prev_Entity, Id, 'c');
3229 Set_Completion_Referenced (Id);
3231 if Error_Posted (N) then
3233 -- Type mismatch or illegal redeclaration, Do not analyze
3234 -- expression to avoid cascaded errors.
3236 T := Find_Type_Of_Object (Object_Definition (N), N);
3238 Set_Ekind (Id, E_Variable);
3242 -- In the normal case, enter identifier at the start to catch premature
3243 -- usage in the initialization expression.
3246 Generate_Definition (Id);
3249 Mark_Coextensions (N, Object_Definition (N));
3251 T := Find_Type_Of_Object (Object_Definition (N), N);
3253 if Nkind (Object_Definition (N)) = N_Access_Definition
3255 (Access_To_Subprogram_Definition (Object_Definition (N)))
3256 and then Protected_Present
3257 (Access_To_Subprogram_Definition (Object_Definition (N)))
3259 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
3262 if Error_Posted (Id) then
3264 Set_Ekind (Id, E_Variable);
3269 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
3270 -- out some static checks
3272 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
3274 -- In case of aggregates we must also take care of the correct
3275 -- initialization of nested aggregates bug this is done at the
3276 -- point of the analysis of the aggregate (see sem_aggr.adb).
3278 if Present (Expression (N))
3279 and then Nkind (Expression (N)) = N_Aggregate
3285 Save_Typ : constant Entity_Id := Etype (Id);
3287 Set_Etype (Id, T); -- Temp. decoration for static checks
3288 Null_Exclusion_Static_Checks (N);
3289 Set_Etype (Id, Save_Typ);
3294 -- Object is marked pure if it is in a pure scope
3296 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3298 -- If deferred constant, make sure context is appropriate. We detect
3299 -- a deferred constant as a constant declaration with no expression.
3300 -- A deferred constant can appear in a package body if its completion
3301 -- is by means of an interface pragma.
3303 if Constant_Present (N) and then No (E) then
3305 -- A deferred constant may appear in the declarative part of the
3306 -- following constructs:
3310 -- extended return statements
3313 -- subprogram bodies
3316 -- When declared inside a package spec, a deferred constant must be
3317 -- completed by a full constant declaration or pragma Import. In all
3318 -- other cases, the only proper completion is pragma Import. Extended
3319 -- return statements are flagged as invalid contexts because they do
3320 -- not have a declarative part and so cannot accommodate the pragma.
3322 if Ekind (Current_Scope) = E_Return_Statement then
3324 ("invalid context for deferred constant declaration (RM 7.4)",
3327 ("\declaration requires an initialization expression",
3329 Set_Constant_Present (N, False);
3331 -- In Ada 83, deferred constant must be of private type
3333 elsif not Is_Private_Type (T) then
3334 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
3336 ("(Ada 83) deferred constant must be private type", N);
3340 -- If not a deferred constant, then object declaration freezes its type
3343 Check_Fully_Declared (T, N);
3344 Freeze_Before (N, T);
3347 -- If the object was created by a constrained array definition, then
3348 -- set the link in both the anonymous base type and anonymous subtype
3349 -- that are built to represent the array type to point to the object.
3351 if Nkind (Object_Definition (Declaration_Node (Id))) =
3352 N_Constrained_Array_Definition
3354 Set_Related_Array_Object (T, Id);
3355 Set_Related_Array_Object (Base_Type (T), Id);
3358 -- Special checks for protected objects not at library level
3360 if Is_Protected_Type (T)
3361 and then not Is_Library_Level_Entity (Id)
3363 Check_Restriction (No_Local_Protected_Objects, Id);
3365 -- Protected objects with interrupt handlers must be at library level
3367 -- Ada 2005: This test is not needed (and the corresponding clause
3368 -- in the RM is removed) because accessibility checks are sufficient
3369 -- to make handlers not at the library level illegal.
3371 -- AI05-0303: The AI is in fact a binding interpretation, and thus
3372 -- applies to the '95 version of the language as well.
3374 if Has_Interrupt_Handler (T) and then Ada_Version < Ada_95 then
3376 ("interrupt object can only be declared at library level", Id);
3380 -- The actual subtype of the object is the nominal subtype, unless
3381 -- the nominal one is unconstrained and obtained from the expression.
3385 -- These checks should be performed before the initialization expression
3386 -- is considered, so that the Object_Definition node is still the same
3387 -- as in source code.
3389 -- In SPARK, the nominal subtype shall be given by a subtype mark and
3390 -- shall not be unconstrained. (The only exception to this is the
3391 -- admission of declarations of constants of type String.)
3394 Nkind_In (Object_Definition (N), N_Identifier, N_Expanded_Name)
3396 Check_SPARK_Restriction
3397 ("subtype mark required", Object_Definition (N));
3399 elsif Is_Array_Type (T)
3400 and then not Is_Constrained (T)
3401 and then T /= Standard_String
3403 Check_SPARK_Restriction
3404 ("subtype mark of constrained type expected",
3405 Object_Definition (N));
3408 -- There are no aliased objects in SPARK
3410 if Aliased_Present (N) then
3411 Check_SPARK_Restriction ("aliased object is not allowed", N);
3414 -- Process initialization expression if present and not in error
3416 if Present (E) and then E /= Error then
3418 -- Generate an error in case of CPP class-wide object initialization.
3419 -- Required because otherwise the expansion of the class-wide
3420 -- assignment would try to use 'size to initialize the object
3421 -- (primitive that is not available in CPP tagged types).
3423 if Is_Class_Wide_Type (Act_T)
3425 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3427 (Present (Full_View (Root_Type (Etype (Act_T))))
3429 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3432 ("predefined assignment not available for 'C'P'P tagged types",
3436 Mark_Coextensions (N, E);
3439 -- In case of errors detected in the analysis of the expression,
3440 -- decorate it with the expected type to avoid cascaded errors
3442 if No (Etype (E)) then
3446 -- If an initialization expression is present, then we set the
3447 -- Is_True_Constant flag. It will be reset if this is a variable
3448 -- and it is indeed modified.
3450 Set_Is_True_Constant (Id, True);
3452 -- If we are analyzing a constant declaration, set its completion
3453 -- flag after analyzing and resolving the expression.
3455 if Constant_Present (N) then
3456 Set_Has_Completion (Id);
3459 -- Set type and resolve (type may be overridden later on). Note:
3460 -- Ekind (Id) must still be E_Void at this point so that incorrect
3461 -- early usage within E is properly diagnosed.
3466 -- No further action needed if E is a call to an inlined function
3467 -- which returns an unconstrained type and it has been expanded into
3468 -- a procedure call. In that case N has been replaced by an object
3469 -- declaration without initializing expression and it has been
3470 -- analyzed (see Expand_Inlined_Call).
3473 and then Expander_Active
3474 and then Nkind (E) = N_Function_Call
3475 and then Nkind (Name (E)) in N_Has_Entity
3476 and then Is_Inlined (Entity (Name (E)))
3477 and then not Is_Constrained (Etype (E))
3478 and then Analyzed (N)
3479 and then No (Expression (N))
3484 -- If E is null and has been replaced by an N_Raise_Constraint_Error
3485 -- node (which was marked already-analyzed), we need to set the type
3486 -- to something other than Any_Access in order to keep gigi happy.
3488 if Etype (E) = Any_Access then
3492 -- If the object is an access to variable, the initialization
3493 -- expression cannot be an access to constant.
3495 if Is_Access_Type (T)
3496 and then not Is_Access_Constant (T)
3497 and then Is_Access_Type (Etype (E))
3498 and then Is_Access_Constant (Etype (E))
3501 ("access to variable cannot be initialized "
3502 & "with an access-to-constant expression", E);
3505 if not Assignment_OK (N) then
3506 Check_Initialization (T, E);
3509 Check_Unset_Reference (E);
3511 -- If this is a variable, then set current value. If this is a
3512 -- declared constant of a scalar type with a static expression,
3513 -- indicate that it is always valid.
3515 if not Constant_Present (N) then
3516 if Compile_Time_Known_Value (E) then
3517 Set_Current_Value (Id, E);
3520 elsif Is_Scalar_Type (T) and then Is_OK_Static_Expression (E) then
3521 Set_Is_Known_Valid (Id);
3524 -- Deal with setting of null flags
3526 if Is_Access_Type (T) then
3527 if Known_Non_Null (E) then
3528 Set_Is_Known_Non_Null (Id, True);
3529 elsif Known_Null (E) and then not Can_Never_Be_Null (Id) then
3530 Set_Is_Known_Null (Id, True);
3534 -- Check incorrect use of dynamically tagged expressions
3536 if Is_Tagged_Type (T) then
3537 Check_Dynamically_Tagged_Expression
3543 Apply_Scalar_Range_Check (E, T);
3544 Apply_Static_Length_Check (E, T);
3546 if Nkind (Original_Node (N)) = N_Object_Declaration
3547 and then Comes_From_Source (Original_Node (N))
3549 -- Only call test if needed
3551 and then Restriction_Check_Required (SPARK_05)
3552 and then not Is_SPARK_Initialization_Expr (Original_Node (E))
3554 Check_SPARK_Restriction
3555 ("initialization expression is not appropriate", E);
3559 -- If the No_Streams restriction is set, check that the type of the
3560 -- object is not, and does not contain, any subtype derived from
3561 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
3562 -- Has_Stream just for efficiency reasons. There is no point in
3563 -- spending time on a Has_Stream check if the restriction is not set.
3565 if Restriction_Check_Required (No_Streams) then
3566 if Has_Stream (T) then
3567 Check_Restriction (No_Streams, N);
3571 -- Deal with predicate check before we start to do major rewriting. It
3572 -- is OK to initialize and then check the initialized value, since the
3573 -- object goes out of scope if we get a predicate failure. Note that we
3574 -- do this in the analyzer and not the expander because the analyzer
3575 -- does some substantial rewriting in some cases.
3577 -- We need a predicate check if the type has predicates, and if either
3578 -- there is an initializing expression, or for default initialization
3579 -- when we have at least one case of an explicit default initial value
3580 -- and then this is not an internal declaration whose initialization
3581 -- comes later (as for an aggregate expansion).
3583 if not Suppress_Assignment_Checks (N)
3584 and then Present (Predicate_Function (T))
3585 and then not No_Initialization (N)
3589 Is_Partially_Initialized_Type (T, Include_Implicit => False))
3591 -- If the type has a static predicate and the expression is known at
3592 -- compile time, see if the expression satisfies the predicate.
3595 Check_Expression_Against_Static_Predicate (E, T);
3599 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
3602 -- Case of unconstrained type
3604 if Is_Indefinite_Subtype (T) then
3606 -- In SPARK, a declaration of unconstrained type is allowed
3607 -- only for constants of type string.
3609 if Is_String_Type (T) and then not Constant_Present (N) then
3610 Check_SPARK_Restriction
3611 ("declaration of object of unconstrained type not allowed", N);
3614 -- Nothing to do in deferred constant case
3616 if Constant_Present (N) and then No (E) then
3619 -- Case of no initialization present
3622 if No_Initialization (N) then
3625 elsif Is_Class_Wide_Type (T) then
3627 ("initialization required in class-wide declaration ", N);
3631 ("unconstrained subtype not allowed (need initialization)",
3632 Object_Definition (N));
3634 if Is_Record_Type (T) and then Has_Discriminants (T) then
3636 ("\provide initial value or explicit discriminant values",
3637 Object_Definition (N));
3640 ("\or give default discriminant values for type&",
3641 Object_Definition (N), T);
3643 elsif Is_Array_Type (T) then
3645 ("\provide initial value or explicit array bounds",
3646 Object_Definition (N));
3650 -- Case of initialization present but in error. Set initial
3651 -- expression as absent (but do not make above complaints)
3653 elsif E = Error then
3654 Set_Expression (N, Empty);
3657 -- Case of initialization present
3660 -- Check restrictions in Ada 83
3662 if not Constant_Present (N) then
3664 -- Unconstrained variables not allowed in Ada 83 mode
3666 if Ada_Version = Ada_83
3667 and then Comes_From_Source (Object_Definition (N))
3670 ("(Ada 83) unconstrained variable not allowed",
3671 Object_Definition (N));
3675 -- Now we constrain the variable from the initializing expression
3677 -- If the expression is an aggregate, it has been expanded into
3678 -- individual assignments. Retrieve the actual type from the
3679 -- expanded construct.
3681 if Is_Array_Type (T)
3682 and then No_Initialization (N)
3683 and then Nkind (Original_Node (E)) = N_Aggregate
3687 -- In case of class-wide interface object declarations we delay
3688 -- the generation of the equivalent record type declarations until
3689 -- its expansion because there are cases in they are not required.
3691 elsif Is_Interface (T) then
3695 Expand_Subtype_From_Expr (N, T, Object_Definition (N), E);
3696 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
3699 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
3701 if Aliased_Present (N) then
3702 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3705 Freeze_Before (N, Act_T);
3706 Freeze_Before (N, T);
3709 elsif Is_Array_Type (T)
3710 and then No_Initialization (N)
3711 and then Nkind (Original_Node (E)) = N_Aggregate
3713 if not Is_Entity_Name (Object_Definition (N)) then
3715 Check_Compile_Time_Size (Act_T);
3717 if Aliased_Present (N) then
3718 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3722 -- When the given object definition and the aggregate are specified
3723 -- independently, and their lengths might differ do a length check.
3724 -- This cannot happen if the aggregate is of the form (others =>...)
3726 if not Is_Constrained (T) then
3729 elsif Nkind (E) = N_Raise_Constraint_Error then
3731 -- Aggregate is statically illegal. Place back in declaration
3733 Set_Expression (N, E);
3734 Set_No_Initialization (N, False);
3736 elsif T = Etype (E) then
3739 elsif Nkind (E) = N_Aggregate
3740 and then Present (Component_Associations (E))
3741 and then Present (Choices (First (Component_Associations (E))))
3742 and then Nkind (First
3743 (Choices (First (Component_Associations (E))))) = N_Others_Choice
3748 Apply_Length_Check (E, T);
3751 -- If the type is limited unconstrained with defaulted discriminants and
3752 -- there is no expression, then the object is constrained by the
3753 -- defaults, so it is worthwhile building the corresponding subtype.
3755 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
3756 and then not Is_Constrained (T)
3757 and then Has_Discriminants (T)
3760 Act_T := Build_Default_Subtype (T, N);
3762 -- Ada 2005: A limited object may be initialized by means of an
3763 -- aggregate. If the type has default discriminants it has an
3764 -- unconstrained nominal type, Its actual subtype will be obtained
3765 -- from the aggregate, and not from the default discriminants.
3770 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
3772 elsif Nkind (E) = N_Function_Call
3773 and then Constant_Present (N)
3774 and then Has_Unconstrained_Elements (Etype (E))
3776 -- The back-end has problems with constants of a discriminated type
3777 -- with defaults, if the initial value is a function call. We
3778 -- generate an intermediate temporary that will receive a reference
3779 -- to the result of the call. The initialization expression then
3780 -- becomes a dereference of that temporary.
3782 Remove_Side_Effects (E);
3784 -- If this is a constant declaration of an unconstrained type and
3785 -- the initialization is an aggregate, we can use the subtype of the
3786 -- aggregate for the declared entity because it is immutable.
3788 elsif not Is_Constrained (T)
3789 and then Has_Discriminants (T)
3790 and then Constant_Present (N)
3791 and then not Has_Unchecked_Union (T)
3792 and then Nkind (E) = N_Aggregate
3797 -- Check No_Wide_Characters restriction
3799 Check_Wide_Character_Restriction (T, Object_Definition (N));
3801 -- Indicate this is not set in source. Certainly true for constants, and
3802 -- true for variables so far (will be reset for a variable if and when
3803 -- we encounter a modification in the source).
3805 Set_Never_Set_In_Source (Id, True);
3807 -- Now establish the proper kind and type of the object
3809 if Constant_Present (N) then
3810 Set_Ekind (Id, E_Constant);
3811 Set_Is_True_Constant (Id);
3814 Set_Ekind (Id, E_Variable);
3816 -- A variable is set as shared passive if it appears in a shared
3817 -- passive package, and is at the outer level. This is not done for
3818 -- entities generated during expansion, because those are always
3819 -- manipulated locally.
3821 if Is_Shared_Passive (Current_Scope)
3822 and then Is_Library_Level_Entity (Id)
3823 and then Comes_From_Source (Id)
3825 Set_Is_Shared_Passive (Id);
3826 Check_Shared_Var (Id, T, N);
3829 -- Set Has_Initial_Value if initializing expression present. Note
3830 -- that if there is no initializing expression, we leave the state
3831 -- of this flag unchanged (usually it will be False, but notably in
3832 -- the case of exception choice variables, it will already be true).
3835 Set_Has_Initial_Value (Id, True);
3838 Set_Contract (Id, Make_Contract (Sloc (Id)));
3841 -- Initialize alignment and size and capture alignment setting
3843 Init_Alignment (Id);
3845 Set_Optimize_Alignment_Flags (Id);
3847 -- Deal with aliased case
3849 if Aliased_Present (N) then
3850 Set_Is_Aliased (Id);
3852 -- If the object is aliased and the type is unconstrained with
3853 -- defaulted discriminants and there is no expression, then the
3854 -- object is constrained by the defaults, so it is worthwhile
3855 -- building the corresponding subtype.
3857 -- Ada 2005 (AI-363): If the aliased object is discriminated and
3858 -- unconstrained, then only establish an actual subtype if the
3859 -- nominal subtype is indefinite. In definite cases the object is
3860 -- unconstrained in Ada 2005.
3863 and then Is_Record_Type (T)
3864 and then not Is_Constrained (T)
3865 and then Has_Discriminants (T)
3866 and then (Ada_Version < Ada_2005 or else Is_Indefinite_Subtype (T))
3868 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
3872 -- Now we can set the type of the object
3874 Set_Etype (Id, Act_T);
3876 -- Object is marked to be treated as volatile if type is volatile and
3877 -- we clear the Current_Value setting that may have been set above.
3879 if Treat_As_Volatile (Etype (Id)) then
3880 Set_Treat_As_Volatile (Id);
3881 Set_Current_Value (Id, Empty);
3884 -- Deal with controlled types
3886 if Has_Controlled_Component (Etype (Id))
3887 or else Is_Controlled (Etype (Id))
3889 if not Is_Library_Level_Entity (Id) then
3890 Check_Restriction (No_Nested_Finalization, N);
3892 Validate_Controlled_Object (Id);
3896 if Has_Task (Etype (Id)) then
3897 Check_Restriction (No_Tasking, N);
3899 -- Deal with counting max tasks
3901 -- Nothing to do if inside a generic
3903 if Inside_A_Generic then
3906 -- If library level entity, then count tasks
3908 elsif Is_Library_Level_Entity (Id) then
3909 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
3911 -- If not library level entity, then indicate we don't know max
3912 -- tasks and also check task hierarchy restriction and blocking
3913 -- operation (since starting a task is definitely blocking).
3916 Check_Restriction (Max_Tasks, N);
3917 Check_Restriction (No_Task_Hierarchy, N);
3918 Check_Potentially_Blocking_Operation (N);
3921 -- A rather specialized test. If we see two tasks being declared
3922 -- of the same type in the same object declaration, and the task
3923 -- has an entry with an address clause, we know that program error
3924 -- will be raised at run time since we can't have two tasks with
3925 -- entries at the same address.
3927 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
3932 E := First_Entity (Etype (Id));
3933 while Present (E) loop
3934 if Ekind (E) = E_Entry
3935 and then Present (Get_Attribute_Definition_Clause
3936 (E, Attribute_Address))
3938 Error_Msg_Warn := SPARK_Mode /= On;
3940 ("more than one task with same entry address<<", N);
3941 Error_Msg_N ("\Program_Error [<<", N);
3943 Make_Raise_Program_Error (Loc,
3944 Reason => PE_Duplicated_Entry_Address));
3954 -- Some simple constant-propagation: if the expression is a constant
3955 -- string initialized with a literal, share the literal. This avoids
3959 and then Is_Entity_Name (E)
3960 and then Ekind (Entity (E)) = E_Constant
3961 and then Base_Type (Etype (E)) = Standard_String
3964 Val : constant Node_Id := Constant_Value (Entity (E));
3966 if Present (Val) and then Nkind (Val) = N_String_Literal then
3967 Rewrite (E, New_Copy (Val));
3972 -- Another optimization: if the nominal subtype is unconstrained and
3973 -- the expression is a function call that returns an unconstrained
3974 -- type, rewrite the declaration as a renaming of the result of the
3975 -- call. The exceptions below are cases where the copy is expected,
3976 -- either by the back end (Aliased case) or by the semantics, as for
3977 -- initializing controlled types or copying tags for classwide types.
3980 and then Nkind (E) = N_Explicit_Dereference
3981 and then Nkind (Original_Node (E)) = N_Function_Call
3982 and then not Is_Library_Level_Entity (Id)
3983 and then not Is_Constrained (Underlying_Type (T))
3984 and then not Is_Aliased (Id)
3985 and then not Is_Class_Wide_Type (T)
3986 and then not Is_Controlled (T)
3987 and then not Has_Controlled_Component (Base_Type (T))
3988 and then Expander_Active
3991 Make_Object_Renaming_Declaration (Loc,
3992 Defining_Identifier => Id,
3993 Access_Definition => Empty,
3994 Subtype_Mark => New_Occurrence_Of
3995 (Base_Type (Etype (Id)), Loc),
3998 Set_Renamed_Object (Id, E);
4000 -- Force generation of debugging information for the constant and for
4001 -- the renamed function call.
4003 Set_Debug_Info_Needed (Id);
4004 Set_Debug_Info_Needed (Entity (Prefix (E)));
4007 if Present (Prev_Entity)
4008 and then Is_Frozen (Prev_Entity)
4009 and then not Error_Posted (Id)
4011 Error_Msg_N ("full constant declaration appears too late", N);
4014 Check_Eliminated (Id);
4016 -- Deal with setting In_Private_Part flag if in private part
4018 if Ekind (Scope (Id)) = E_Package and then In_Private_Part (Scope (Id))
4020 Set_In_Private_Part (Id);
4023 -- Check for violation of No_Local_Timing_Events
4025 if Restriction_Check_Required (No_Local_Timing_Events)
4026 and then not Is_Library_Level_Entity (Id)
4027 and then Is_RTE (Etype (Id), RE_Timing_Event)
4029 Check_Restriction (No_Local_Timing_Events, N);
4033 -- Initialize the refined state of a variable here because this is a
4034 -- common destination for legal and illegal object declarations.
4036 if Ekind (Id) = E_Variable then
4037 Set_Encapsulating_State (Id, Empty);
4040 if Has_Aspects (N) then
4041 Analyze_Aspect_Specifications (N, Id);
4044 Analyze_Dimension (N);
4046 -- Verify whether the object declaration introduces an illegal hidden
4047 -- state within a package subject to a null abstract state.
4049 if Ekind (Id) = E_Variable then
4050 Check_No_Hidden_State (Id);
4052 end Analyze_Object_Declaration;
4054 ---------------------------
4055 -- Analyze_Others_Choice --
4056 ---------------------------
4058 -- Nothing to do for the others choice node itself, the semantic analysis
4059 -- of the others choice will occur as part of the processing of the parent
4061 procedure Analyze_Others_Choice (N : Node_Id) is
4062 pragma Warnings (Off, N);
4065 end Analyze_Others_Choice;
4067 -------------------------------------------
4068 -- Analyze_Private_Extension_Declaration --
4069 -------------------------------------------
4071 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
4072 T : constant Entity_Id := Defining_Identifier (N);
4073 Indic : constant Node_Id := Subtype_Indication (N);
4074 Parent_Type : Entity_Id;
4075 Parent_Base : Entity_Id;
4078 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
4080 if Is_Non_Empty_List (Interface_List (N)) then
4086 Intf := First (Interface_List (N));
4087 while Present (Intf) loop
4088 T := Find_Type_Of_Subtype_Indic (Intf);
4090 Diagnose_Interface (Intf, T);
4096 Generate_Definition (T);
4098 -- For other than Ada 2012, just enter the name in the current scope
4100 if Ada_Version < Ada_2012 then
4103 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
4104 -- case of private type that completes an incomplete type.
4111 Prev := Find_Type_Name (N);
4113 pragma Assert (Prev = T
4114 or else (Ekind (Prev) = E_Incomplete_Type
4115 and then Present (Full_View (Prev))
4116 and then Full_View (Prev) = T));
4120 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
4121 Parent_Base := Base_Type (Parent_Type);
4123 if Parent_Type = Any_Type
4124 or else Etype (Parent_Type) = Any_Type
4126 Set_Ekind (T, Ekind (Parent_Type));
4127 Set_Etype (T, Any_Type);
4130 elsif not Is_Tagged_Type (Parent_Type) then
4132 ("parent of type extension must be a tagged type ", Indic);
4135 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
4136 Error_Msg_N ("premature derivation of incomplete type", Indic);
4139 elsif Is_Concurrent_Type (Parent_Type) then
4141 ("parent type of a private extension cannot be "
4142 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
4144 Set_Etype (T, Any_Type);
4145 Set_Ekind (T, E_Limited_Private_Type);
4146 Set_Private_Dependents (T, New_Elmt_List);
4147 Set_Error_Posted (T);
4151 -- Perhaps the parent type should be changed to the class-wide type's
4152 -- specific type in this case to prevent cascading errors ???
4154 if Is_Class_Wide_Type (Parent_Type) then
4156 ("parent of type extension must not be a class-wide type", Indic);
4160 if (not Is_Package_Or_Generic_Package (Current_Scope)
4161 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
4162 or else In_Private_Part (Current_Scope)
4165 Error_Msg_N ("invalid context for private extension", N);
4168 -- Set common attributes
4170 Set_Is_Pure (T, Is_Pure (Current_Scope));
4171 Set_Scope (T, Current_Scope);
4172 Set_Ekind (T, E_Record_Type_With_Private);
4173 Init_Size_Align (T);
4175 Set_Etype (T, Parent_Base);
4176 Set_Has_Task (T, Has_Task (Parent_Base));
4178 Set_Convention (T, Convention (Parent_Type));
4179 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
4180 Set_Is_First_Subtype (T);
4181 Make_Class_Wide_Type (T);
4183 if Unknown_Discriminants_Present (N) then
4184 Set_Discriminant_Constraint (T, No_Elist);
4187 Build_Derived_Record_Type (N, Parent_Type, T);
4189 -- Propagate inherited invariant information. The new type has
4190 -- invariants, if the parent type has inheritable invariants,
4191 -- and these invariants can in turn be inherited.
4193 if Has_Inheritable_Invariants (Parent_Type) then
4194 Set_Has_Inheritable_Invariants (T);
4195 Set_Has_Invariants (T);
4198 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
4199 -- synchronized formal derived type.
4201 if Ada_Version >= Ada_2005 and then Synchronized_Present (N) then
4202 Set_Is_Limited_Record (T);
4204 -- Formal derived type case
4206 if Is_Generic_Type (T) then
4208 -- The parent must be a tagged limited type or a synchronized
4211 if (not Is_Tagged_Type (Parent_Type)
4212 or else not Is_Limited_Type (Parent_Type))
4214 (not Is_Interface (Parent_Type)
4215 or else not Is_Synchronized_Interface (Parent_Type))
4217 Error_Msg_NE ("parent type of & must be tagged limited " &
4218 "or synchronized", N, T);
4221 -- The progenitors (if any) must be limited or synchronized
4224 if Present (Interfaces (T)) then
4227 Iface_Elmt : Elmt_Id;
4230 Iface_Elmt := First_Elmt (Interfaces (T));
4231 while Present (Iface_Elmt) loop
4232 Iface := Node (Iface_Elmt);
4234 if not Is_Limited_Interface (Iface)
4235 and then not Is_Synchronized_Interface (Iface)
4237 Error_Msg_NE ("progenitor & must be limited " &
4238 "or synchronized", N, Iface);
4241 Next_Elmt (Iface_Elmt);
4246 -- Regular derived extension, the parent must be a limited or
4247 -- synchronized interface.
4250 if not Is_Interface (Parent_Type)
4251 or else (not Is_Limited_Interface (Parent_Type)
4252 and then not Is_Synchronized_Interface (Parent_Type))
4255 ("parent type of & must be limited interface", N, T);
4259 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
4260 -- extension with a synchronized parent must be explicitly declared
4261 -- synchronized, because the full view will be a synchronized type.
4262 -- This must be checked before the check for limited types below,
4263 -- to ensure that types declared limited are not allowed to extend
4264 -- synchronized interfaces.
4266 elsif Is_Interface (Parent_Type)
4267 and then Is_Synchronized_Interface (Parent_Type)
4268 and then not Synchronized_Present (N)
4271 ("private extension of& must be explicitly synchronized",
4274 elsif Limited_Present (N) then
4275 Set_Is_Limited_Record (T);
4277 if not Is_Limited_Type (Parent_Type)
4279 (not Is_Interface (Parent_Type)
4280 or else not Is_Limited_Interface (Parent_Type))
4282 Error_Msg_NE ("parent type& of limited extension must be limited",
4288 if Has_Aspects (N) then
4289 Analyze_Aspect_Specifications (N, T);
4291 end Analyze_Private_Extension_Declaration;
4293 ---------------------------------
4294 -- Analyze_Subtype_Declaration --
4295 ---------------------------------
4297 procedure Analyze_Subtype_Declaration
4299 Skip : Boolean := False)
4301 Id : constant Entity_Id := Defining_Identifier (N);
4303 R_Checks : Check_Result;
4306 Generate_Definition (Id);
4307 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4308 Init_Size_Align (Id);
4310 -- The following guard condition on Enter_Name is to handle cases where
4311 -- the defining identifier has already been entered into the scope but
4312 -- the declaration as a whole needs to be analyzed.
4314 -- This case in particular happens for derived enumeration types. The
4315 -- derived enumeration type is processed as an inserted enumeration type
4316 -- declaration followed by a rewritten subtype declaration. The defining
4317 -- identifier, however, is entered into the name scope very early in the
4318 -- processing of the original type declaration and therefore needs to be
4319 -- avoided here, when the created subtype declaration is analyzed. (See
4320 -- Build_Derived_Types)
4322 -- This also happens when the full view of a private type is derived
4323 -- type with constraints. In this case the entity has been introduced
4324 -- in the private declaration.
4326 -- Finally this happens in some complex cases when validity checks are
4327 -- enabled, where the same subtype declaration may be analyzed twice.
4328 -- This can happen if the subtype is created by the pre-analysis of
4329 -- an attribute tht gives the range of a loop statement, and the loop
4330 -- itself appears within an if_statement that will be rewritten during
4334 or else (Present (Etype (Id))
4335 and then (Is_Private_Type (Etype (Id))
4336 or else Is_Task_Type (Etype (Id))
4337 or else Is_Rewrite_Substitution (N)))
4341 elsif Current_Entity (Id) = Id then
4348 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4350 -- Class-wide equivalent types of records with unknown discriminants
4351 -- involve the generation of an itype which serves as the private view
4352 -- of a constrained record subtype. In such cases the base type of the
4353 -- current subtype we are processing is the private itype. Use the full
4354 -- of the private itype when decorating various attributes.
4357 and then Is_Private_Type (T)
4358 and then Present (Full_View (T))
4363 -- Inherit common attributes
4365 Set_Is_Volatile (Id, Is_Volatile (T));
4366 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4367 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4368 Set_Convention (Id, Convention (T));
4370 -- If ancestor has predicates then so does the subtype, and in addition
4371 -- we must delay the freeze to properly arrange predicate inheritance.
4373 -- The Ancestor_Type test is really unpleasant, there seem to be cases
4374 -- in which T = ID, so the above tests and assignments do nothing???
4376 if Has_Predicates (T)
4377 or else (Present (Ancestor_Subtype (T))
4378 and then Has_Predicates (Ancestor_Subtype (T)))
4380 Set_Has_Predicates (Id);
4381 Set_Has_Delayed_Freeze (Id);
4384 -- Subtype of Boolean cannot have a constraint in SPARK
4386 if Is_Boolean_Type (T)
4387 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4389 Check_SPARK_Restriction
4390 ("subtype of Boolean cannot have constraint", N);
4393 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4395 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4401 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4402 One_Cstr := First (Constraints (Cstr));
4403 while Present (One_Cstr) loop
4405 -- Index or discriminant constraint in SPARK must be a
4409 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4411 Check_SPARK_Restriction
4412 ("subtype mark required", One_Cstr);
4414 -- String subtype must have a lower bound of 1 in SPARK.
4415 -- Note that we do not need to test for the non-static case
4416 -- here, since that was already taken care of in
4417 -- Process_Range_Expr_In_Decl.
4419 elsif Base_Type (T) = Standard_String then
4420 Get_Index_Bounds (One_Cstr, Low, High);
4422 if Is_OK_Static_Expression (Low)
4423 and then Expr_Value (Low) /= 1
4425 Check_SPARK_Restriction
4426 ("String subtype must have lower bound of 1", N);
4436 -- In the case where there is no constraint given in the subtype
4437 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4438 -- semantic attributes must be established here.
4440 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
4441 Set_Etype (Id, Base_Type (T));
4443 -- Subtype of unconstrained array without constraint is not allowed
4446 if Is_Array_Type (T) and then not Is_Constrained (T) then
4447 Check_SPARK_Restriction
4448 ("subtype of unconstrained array must have constraint", N);
4453 Set_Ekind (Id, E_Array_Subtype);
4454 Copy_Array_Subtype_Attributes (Id, T);
4456 when Decimal_Fixed_Point_Kind =>
4457 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
4458 Set_Digits_Value (Id, Digits_Value (T));
4459 Set_Delta_Value (Id, Delta_Value (T));
4460 Set_Scale_Value (Id, Scale_Value (T));
4461 Set_Small_Value (Id, Small_Value (T));
4462 Set_Scalar_Range (Id, Scalar_Range (T));
4463 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
4464 Set_Is_Constrained (Id, Is_Constrained (T));
4465 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4466 Set_RM_Size (Id, RM_Size (T));
4468 when Enumeration_Kind =>
4469 Set_Ekind (Id, E_Enumeration_Subtype);
4470 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4471 Set_Scalar_Range (Id, Scalar_Range (T));
4472 Set_Is_Character_Type (Id, Is_Character_Type (T));
4473 Set_Is_Constrained (Id, Is_Constrained (T));
4474 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4475 Set_RM_Size (Id, RM_Size (T));
4477 when Ordinary_Fixed_Point_Kind =>
4478 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4479 Set_Scalar_Range (Id, Scalar_Range (T));
4480 Set_Small_Value (Id, Small_Value (T));
4481 Set_Delta_Value (Id, Delta_Value (T));
4482 Set_Is_Constrained (Id, Is_Constrained (T));
4483 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4484 Set_RM_Size (Id, RM_Size (T));
4487 Set_Ekind (Id, E_Floating_Point_Subtype);
4488 Set_Scalar_Range (Id, Scalar_Range (T));
4489 Set_Digits_Value (Id, Digits_Value (T));
4490 Set_Is_Constrained (Id, Is_Constrained (T));
4492 when Signed_Integer_Kind =>
4493 Set_Ekind (Id, E_Signed_Integer_Subtype);
4494 Set_Scalar_Range (Id, Scalar_Range (T));
4495 Set_Is_Constrained (Id, Is_Constrained (T));
4496 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4497 Set_RM_Size (Id, RM_Size (T));
4499 when Modular_Integer_Kind =>
4500 Set_Ekind (Id, E_Modular_Integer_Subtype);
4501 Set_Scalar_Range (Id, Scalar_Range (T));
4502 Set_Is_Constrained (Id, Is_Constrained (T));
4503 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4504 Set_RM_Size (Id, RM_Size (T));
4506 when Class_Wide_Kind =>
4507 Set_Ekind (Id, E_Class_Wide_Subtype);
4508 Set_First_Entity (Id, First_Entity (T));
4509 Set_Last_Entity (Id, Last_Entity (T));
4510 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4511 Set_Cloned_Subtype (Id, T);
4512 Set_Is_Tagged_Type (Id, True);
4513 Set_Has_Unknown_Discriminants
4516 if Ekind (T) = E_Class_Wide_Subtype then
4517 Set_Equivalent_Type (Id, Equivalent_Type (T));
4520 when E_Record_Type | E_Record_Subtype =>
4521 Set_Ekind (Id, E_Record_Subtype);
4523 if Ekind (T) = E_Record_Subtype
4524 and then Present (Cloned_Subtype (T))
4526 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
4528 Set_Cloned_Subtype (Id, T);
4531 Set_First_Entity (Id, First_Entity (T));
4532 Set_Last_Entity (Id, Last_Entity (T));
4533 Set_Has_Discriminants (Id, Has_Discriminants (T));
4534 Set_Is_Constrained (Id, Is_Constrained (T));
4535 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4536 Set_Has_Implicit_Dereference
4537 (Id, Has_Implicit_Dereference (T));
4538 Set_Has_Unknown_Discriminants
4539 (Id, Has_Unknown_Discriminants (T));
4541 if Has_Discriminants (T) then
4542 Set_Discriminant_Constraint
4543 (Id, Discriminant_Constraint (T));
4544 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4546 elsif Has_Unknown_Discriminants (Id) then
4547 Set_Discriminant_Constraint (Id, No_Elist);
4550 if Is_Tagged_Type (T) then
4551 Set_Is_Tagged_Type (Id);
4552 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4553 Set_Direct_Primitive_Operations
4554 (Id, Direct_Primitive_Operations (T));
4555 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4557 if Is_Interface (T) then
4558 Set_Is_Interface (Id);
4559 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
4563 when Private_Kind =>
4564 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4565 Set_Has_Discriminants (Id, Has_Discriminants (T));
4566 Set_Is_Constrained (Id, Is_Constrained (T));
4567 Set_First_Entity (Id, First_Entity (T));
4568 Set_Last_Entity (Id, Last_Entity (T));
4569 Set_Private_Dependents (Id, New_Elmt_List);
4570 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4571 Set_Has_Implicit_Dereference
4572 (Id, Has_Implicit_Dereference (T));
4573 Set_Has_Unknown_Discriminants
4574 (Id, Has_Unknown_Discriminants (T));
4575 Set_Known_To_Have_Preelab_Init
4576 (Id, Known_To_Have_Preelab_Init (T));
4578 if Is_Tagged_Type (T) then
4579 Set_Is_Tagged_Type (Id);
4580 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4581 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4582 Set_Direct_Primitive_Operations (Id,
4583 Direct_Primitive_Operations (T));
4586 -- In general the attributes of the subtype of a private type
4587 -- are the attributes of the partial view of parent. However,
4588 -- the full view may be a discriminated type, and the subtype
4589 -- must share the discriminant constraint to generate correct
4590 -- calls to initialization procedures.
4592 if Has_Discriminants (T) then
4593 Set_Discriminant_Constraint
4594 (Id, Discriminant_Constraint (T));
4595 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4597 elsif Present (Full_View (T))
4598 and then Has_Discriminants (Full_View (T))
4600 Set_Discriminant_Constraint
4601 (Id, Discriminant_Constraint (Full_View (T)));
4602 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4604 -- This would seem semantically correct, but apparently
4605 -- generates spurious errors about missing components ???
4607 -- Set_Has_Discriminants (Id);
4610 Prepare_Private_Subtype_Completion (Id, N);
4612 -- If this is the subtype of a constrained private type with
4613 -- discriminants that has got a full view and we also have
4614 -- built a completion just above, show that the completion
4615 -- is a clone of the full view to the back-end.
4617 if Has_Discriminants (T)
4618 and then not Has_Unknown_Discriminants (T)
4619 and then not Is_Empty_Elmt_List (Discriminant_Constraint (T))
4620 and then Present (Full_View (T))
4621 and then Present (Full_View (Id))
4623 Set_Cloned_Subtype (Full_View (Id), Full_View (T));
4627 Set_Ekind (Id, E_Access_Subtype);
4628 Set_Is_Constrained (Id, Is_Constrained (T));
4629 Set_Is_Access_Constant
4630 (Id, Is_Access_Constant (T));
4631 Set_Directly_Designated_Type
4632 (Id, Designated_Type (T));
4633 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
4635 -- A Pure library_item must not contain the declaration of a
4636 -- named access type, except within a subprogram, generic
4637 -- subprogram, task unit, or protected unit, or if it has
4638 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
4640 if Comes_From_Source (Id)
4641 and then In_Pure_Unit
4642 and then not In_Subprogram_Task_Protected_Unit
4643 and then not No_Pool_Assigned (Id)
4646 ("named access types not allowed in pure unit", N);
4649 when Concurrent_Kind =>
4650 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4651 Set_Corresponding_Record_Type (Id,
4652 Corresponding_Record_Type (T));
4653 Set_First_Entity (Id, First_Entity (T));
4654 Set_First_Private_Entity (Id, First_Private_Entity (T));
4655 Set_Has_Discriminants (Id, Has_Discriminants (T));
4656 Set_Is_Constrained (Id, Is_Constrained (T));
4657 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4658 Set_Last_Entity (Id, Last_Entity (T));
4660 if Has_Discriminants (T) then
4661 Set_Discriminant_Constraint (Id,
4662 Discriminant_Constraint (T));
4663 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4666 when E_Incomplete_Type =>
4667 if Ada_Version >= Ada_2005 then
4669 -- In Ada 2005 an incomplete type can be explicitly tagged:
4670 -- propagate indication.
4672 Set_Ekind (Id, E_Incomplete_Subtype);
4673 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4674 Set_Private_Dependents (Id, New_Elmt_List);
4676 -- Ada 2005 (AI-412): Decorate an incomplete subtype of an
4677 -- incomplete type visible through a limited with clause.
4679 if From_Limited_With (T)
4680 and then Present (Non_Limited_View (T))
4682 Set_From_Limited_With (Id);
4683 Set_Non_Limited_View (Id, Non_Limited_View (T));
4685 -- Ada 2005 (AI-412): Add the regular incomplete subtype
4686 -- to the private dependents of the original incomplete
4687 -- type for future transformation.
4690 Append_Elmt (Id, Private_Dependents (T));
4693 -- If the subtype name denotes an incomplete type an error
4694 -- was already reported by Process_Subtype.
4697 Set_Etype (Id, Any_Type);
4701 raise Program_Error;
4705 if Etype (Id) = Any_Type then
4709 -- Some common processing on all types
4711 Set_Size_Info (Id, T);
4712 Set_First_Rep_Item (Id, First_Rep_Item (T));
4714 -- If the parent type is a generic actual, so is the subtype. This may
4715 -- happen in a nested instance. Why Comes_From_Source test???
4717 if not Comes_From_Source (N) then
4718 Set_Is_Generic_Actual_Type (Id, Is_Generic_Actual_Type (T));
4723 Set_Is_Immediately_Visible (Id, True);
4724 Set_Depends_On_Private (Id, Has_Private_Component (T));
4725 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
4727 if Is_Interface (T) then
4728 Set_Is_Interface (Id);
4731 if Present (Generic_Parent_Type (N))
4733 (Nkind (Parent (Generic_Parent_Type (N))) /=
4734 N_Formal_Type_Declaration
4736 (Formal_Type_Definition (Parent (Generic_Parent_Type (N)))) /=
4737 N_Formal_Private_Type_Definition)
4739 if Is_Tagged_Type (Id) then
4741 -- If this is a generic actual subtype for a synchronized type,
4742 -- the primitive operations are those of the corresponding record
4743 -- for which there is a separate subtype declaration.
4745 if Is_Concurrent_Type (Id) then
4747 elsif Is_Class_Wide_Type (Id) then
4748 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
4750 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
4753 elsif Scope (Etype (Id)) /= Standard_Standard then
4754 Derive_Subprograms (Generic_Parent_Type (N), Id);
4758 if Is_Private_Type (T) and then Present (Full_View (T)) then
4759 Conditional_Delay (Id, Full_View (T));
4761 -- The subtypes of components or subcomponents of protected types
4762 -- do not need freeze nodes, which would otherwise appear in the
4763 -- wrong scope (before the freeze node for the protected type). The
4764 -- proper subtypes are those of the subcomponents of the corresponding
4767 elsif Ekind (Scope (Id)) /= E_Protected_Type
4768 and then Present (Scope (Scope (Id))) -- error defense
4769 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
4771 Conditional_Delay (Id, T);
4774 -- Check that Constraint_Error is raised for a scalar subtype indication
4775 -- when the lower or upper bound of a non-null range lies outside the
4776 -- range of the type mark.
4778 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4779 if Is_Scalar_Type (Etype (Id))
4780 and then Scalar_Range (Id) /=
4781 Scalar_Range (Etype (Subtype_Mark
4782 (Subtype_Indication (N))))
4786 Etype (Subtype_Mark (Subtype_Indication (N))));
4788 -- In the array case, check compatibility for each index
4790 elsif Is_Array_Type (Etype (Id)) and then Present (First_Index (Id))
4792 -- This really should be a subprogram that finds the indications
4796 Subt_Index : Node_Id := First_Index (Id);
4797 Target_Index : Node_Id :=
4799 (Subtype_Mark (Subtype_Indication (N))));
4800 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
4803 while Present (Subt_Index) loop
4804 if ((Nkind (Subt_Index) = N_Identifier
4805 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
4806 or else Nkind (Subt_Index) = N_Subtype_Indication)
4808 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
4811 Target_Typ : constant Entity_Id :=
4812 Etype (Target_Index);
4816 (Scalar_Range (Etype (Subt_Index)),
4819 Defining_Identifier (N));
4821 -- Reset Has_Dynamic_Range_Check on the subtype to
4822 -- prevent elision of the index check due to a dynamic
4823 -- check generated for a preceding index (needed since
4824 -- Insert_Range_Checks tries to avoid generating
4825 -- redundant checks on a given declaration).
4827 Set_Has_Dynamic_Range_Check (N, False);
4833 Sloc (Defining_Identifier (N)));
4835 -- Record whether this index involved a dynamic check
4838 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
4842 Next_Index (Subt_Index);
4843 Next_Index (Target_Index);
4846 -- Finally, mark whether the subtype involves dynamic checks
4848 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
4853 -- Make sure that generic actual types are properly frozen. The subtype
4854 -- is marked as a generic actual type when the enclosing instance is
4855 -- analyzed, so here we identify the subtype from the tree structure.
4858 and then Is_Generic_Actual_Type (Id)
4859 and then In_Instance
4860 and then not Comes_From_Source (N)
4861 and then Nkind (Subtype_Indication (N)) /= N_Subtype_Indication
4862 and then Is_Frozen (T)
4864 Freeze_Before (N, Id);
4867 Set_Optimize_Alignment_Flags (Id);
4868 Check_Eliminated (Id);
4871 if Has_Aspects (N) then
4872 Analyze_Aspect_Specifications (N, Id);
4875 Analyze_Dimension (N);
4876 end Analyze_Subtype_Declaration;
4878 --------------------------------
4879 -- Analyze_Subtype_Indication --
4880 --------------------------------
4882 procedure Analyze_Subtype_Indication (N : Node_Id) is
4883 T : constant Entity_Id := Subtype_Mark (N);
4884 R : constant Node_Id := Range_Expression (Constraint (N));
4891 Set_Etype (N, Etype (R));
4892 Resolve (R, Entity (T));
4894 Set_Error_Posted (R);
4895 Set_Error_Posted (T);
4897 end Analyze_Subtype_Indication;
4899 --------------------------
4900 -- Analyze_Variant_Part --
4901 --------------------------
4903 procedure Analyze_Variant_Part (N : Node_Id) is
4904 Discr_Name : Node_Id;
4905 Discr_Type : Entity_Id;
4907 procedure Process_Variant (A : Node_Id);
4908 -- Analyze declarations for a single variant
4910 package Analyze_Variant_Choices is
4911 new Generic_Analyze_Choices (Process_Variant);
4912 use Analyze_Variant_Choices;
4914 ---------------------
4915 -- Process_Variant --
4916 ---------------------
4918 procedure Process_Variant (A : Node_Id) is
4919 CL : constant Node_Id := Component_List (A);
4921 if not Null_Present (CL) then
4922 Analyze_Declarations (Component_Items (CL));
4924 if Present (Variant_Part (CL)) then
4925 Analyze (Variant_Part (CL));
4928 end Process_Variant;
4930 -- Start of processing for Analyze_Variant_Part
4933 Discr_Name := Name (N);
4934 Analyze (Discr_Name);
4936 -- If Discr_Name bad, get out (prevent cascaded errors)
4938 if Etype (Discr_Name) = Any_Type then
4942 -- Check invalid discriminant in variant part
4944 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
4945 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
4948 Discr_Type := Etype (Entity (Discr_Name));
4950 if not Is_Discrete_Type (Discr_Type) then
4952 ("discriminant in a variant part must be of a discrete type",
4957 -- Now analyze the choices, which also analyzes the declarations that
4958 -- are associated with each choice.
4960 Analyze_Choices (Variants (N), Discr_Type);
4962 -- Note: we used to instantiate and call Check_Choices here to check
4963 -- that the choices covered the discriminant, but it's too early to do
4964 -- that because of statically predicated subtypes, whose analysis may
4965 -- be deferred to their freeze point which may be as late as the freeze
4966 -- point of the containing record. So this call is now to be found in
4967 -- Freeze_Record_Declaration.
4969 end Analyze_Variant_Part;
4971 ----------------------------
4972 -- Array_Type_Declaration --
4973 ----------------------------
4975 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
4976 Component_Def : constant Node_Id := Component_Definition (Def);
4977 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
4978 Element_Type : Entity_Id;
4979 Implicit_Base : Entity_Id;
4981 Related_Id : Entity_Id := Empty;
4983 P : constant Node_Id := Parent (Def);
4987 if Nkind (Def) = N_Constrained_Array_Definition then
4988 Index := First (Discrete_Subtype_Definitions (Def));
4990 Index := First (Subtype_Marks (Def));
4993 -- Find proper names for the implicit types which may be public. In case
4994 -- of anonymous arrays we use the name of the first object of that type
4998 Related_Id := Defining_Identifier (P);
5004 while Present (Index) loop
5007 -- Test for odd case of trying to index a type by the type itself
5009 if Is_Entity_Name (Index) and then Entity (Index) = T then
5010 Error_Msg_N ("type& cannot be indexed by itself", Index);
5011 Set_Entity (Index, Standard_Boolean);
5012 Set_Etype (Index, Standard_Boolean);
5015 -- Check SPARK restriction requiring a subtype mark
5017 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
5018 Check_SPARK_Restriction ("subtype mark required", Index);
5021 -- Add a subtype declaration for each index of private array type
5022 -- declaration whose etype is also private. For example:
5025 -- type Index is private;
5027 -- type Table is array (Index) of ...
5030 -- This is currently required by the expander for the internally
5031 -- generated equality subprogram of records with variant parts in
5032 -- which the etype of some component is such private type.
5034 if Ekind (Current_Scope) = E_Package
5035 and then In_Private_Part (Current_Scope)
5036 and then Has_Private_Declaration (Etype (Index))
5039 Loc : constant Source_Ptr := Sloc (Def);
5044 New_E := Make_Temporary (Loc, 'T');
5045 Set_Is_Internal (New_E);
5048 Make_Subtype_Declaration (Loc,
5049 Defining_Identifier => New_E,
5050 Subtype_Indication =>
5051 New_Occurrence_Of (Etype (Index), Loc));
5053 Insert_Before (Parent (Def), Decl);
5055 Set_Etype (Index, New_E);
5057 -- If the index is a range the Entity attribute is not
5058 -- available. Example:
5061 -- type T is private;
5063 -- type T is new Natural;
5064 -- Table : array (T(1) .. T(10)) of Boolean;
5067 if Nkind (Index) /= N_Range then
5068 Set_Entity (Index, New_E);
5073 Make_Index (Index, P, Related_Id, Nb_Index);
5075 -- Check error of subtype with predicate for index type
5077 Bad_Predicated_Subtype_Use
5078 ("subtype& has predicate, not allowed as index subtype",
5079 Index, Etype (Index));
5081 -- Move to next index
5084 Nb_Index := Nb_Index + 1;
5087 -- Process subtype indication if one is present
5089 if Present (Component_Typ) then
5090 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
5092 Set_Etype (Component_Typ, Element_Type);
5094 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
5095 Check_SPARK_Restriction ("subtype mark required", Component_Typ);
5098 -- Ada 2005 (AI-230): Access Definition case
5100 else pragma Assert (Present (Access_Definition (Component_Def)));
5102 -- Indicate that the anonymous access type is created by the
5103 -- array type declaration.
5105 Element_Type := Access_Definition
5107 N => Access_Definition (Component_Def));
5108 Set_Is_Local_Anonymous_Access (Element_Type);
5110 -- Propagate the parent. This field is needed if we have to generate
5111 -- the master_id associated with an anonymous access to task type
5112 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
5114 Set_Parent (Element_Type, Parent (T));
5116 -- Ada 2005 (AI-230): In case of components that are anonymous access
5117 -- types the level of accessibility depends on the enclosing type
5120 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
5122 -- Ada 2005 (AI-254)
5125 CD : constant Node_Id :=
5126 Access_To_Subprogram_Definition
5127 (Access_Definition (Component_Def));
5129 if Present (CD) and then Protected_Present (CD) then
5131 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
5136 -- Constrained array case
5139 T := Create_Itype (E_Void, P, Related_Id, 'T');
5142 if Nkind (Def) = N_Constrained_Array_Definition then
5144 -- Establish Implicit_Base as unconstrained base type
5146 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
5148 Set_Etype (Implicit_Base, Implicit_Base);
5149 Set_Scope (Implicit_Base, Current_Scope);
5150 Set_Has_Delayed_Freeze (Implicit_Base);
5152 -- The constrained array type is a subtype of the unconstrained one
5154 Set_Ekind (T, E_Array_Subtype);
5155 Init_Size_Align (T);
5156 Set_Etype (T, Implicit_Base);
5157 Set_Scope (T, Current_Scope);
5158 Set_Is_Constrained (T, True);
5159 Set_First_Index (T, First (Discrete_Subtype_Definitions (Def)));
5160 Set_Has_Delayed_Freeze (T);
5162 -- Complete setup of implicit base type
5164 Set_First_Index (Implicit_Base, First_Index (T));
5165 Set_Component_Type (Implicit_Base, Element_Type);
5166 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
5167 Set_Component_Size (Implicit_Base, Uint_0);
5168 Set_Packed_Array_Type (Implicit_Base, Empty);
5169 Set_Has_Controlled_Component
5170 (Implicit_Base, Has_Controlled_Component
5172 or else Is_Controlled
5174 Set_Finalize_Storage_Only
5175 (Implicit_Base, Finalize_Storage_Only
5178 -- Unconstrained array case
5181 Set_Ekind (T, E_Array_Type);
5182 Init_Size_Align (T);
5184 Set_Scope (T, Current_Scope);
5185 Set_Component_Size (T, Uint_0);
5186 Set_Is_Constrained (T, False);
5187 Set_First_Index (T, First (Subtype_Marks (Def)));
5188 Set_Has_Delayed_Freeze (T, True);
5189 Set_Has_Task (T, Has_Task (Element_Type));
5190 Set_Has_Controlled_Component (T, Has_Controlled_Component
5193 Is_Controlled (Element_Type));
5194 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
5198 -- Common attributes for both cases
5200 Set_Component_Type (Base_Type (T), Element_Type);
5201 Set_Packed_Array_Type (T, Empty);
5203 if Aliased_Present (Component_Definition (Def)) then
5204 Check_SPARK_Restriction
5205 ("aliased is not allowed", Component_Definition (Def));
5206 Set_Has_Aliased_Components (Etype (T));
5209 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
5210 -- array type to ensure that objects of this type are initialized.
5212 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (Element_Type) then
5213 Set_Can_Never_Be_Null (T);
5215 if Null_Exclusion_Present (Component_Definition (Def))
5217 -- No need to check itypes because in their case this check was
5218 -- done at their point of creation
5220 and then not Is_Itype (Element_Type)
5223 ("`NOT NULL` not allowed (null already excluded)",
5224 Subtype_Indication (Component_Definition (Def)));
5228 Priv := Private_Component (Element_Type);
5230 if Present (Priv) then
5232 -- Check for circular definitions
5234 if Priv = Any_Type then
5235 Set_Component_Type (Etype (T), Any_Type);
5237 -- There is a gap in the visibility of operations on the composite
5238 -- type only if the component type is defined in a different scope.
5240 elsif Scope (Priv) = Current_Scope then
5243 elsif Is_Limited_Type (Priv) then
5244 Set_Is_Limited_Composite (Etype (T));
5245 Set_Is_Limited_Composite (T);
5247 Set_Is_Private_Composite (Etype (T));
5248 Set_Is_Private_Composite (T);
5252 -- A syntax error in the declaration itself may lead to an empty index
5253 -- list, in which case do a minimal patch.
5255 if No (First_Index (T)) then
5256 Error_Msg_N ("missing index definition in array type declaration", T);
5259 Indexes : constant List_Id :=
5260 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
5262 Set_Discrete_Subtype_Definitions (Def, Indexes);
5263 Set_First_Index (T, First (Indexes));
5268 -- Create a concatenation operator for the new type. Internal array
5269 -- types created for packed entities do not need such, they are
5270 -- compatible with the user-defined type.
5272 if Number_Dimensions (T) = 1 and then not Is_Packed_Array_Type (T) then
5273 New_Concatenation_Op (T);
5276 -- In the case of an unconstrained array the parser has already verified
5277 -- that all the indexes are unconstrained but we still need to make sure
5278 -- that the element type is constrained.
5280 if Is_Indefinite_Subtype (Element_Type) then
5282 ("unconstrained element type in array declaration",
5283 Subtype_Indication (Component_Def));
5285 elsif Is_Abstract_Type (Element_Type) then
5287 ("the type of a component cannot be abstract",
5288 Subtype_Indication (Component_Def));
5291 -- There may be an invariant declared for the component type, but
5292 -- the construction of the component invariant checking procedure
5293 -- takes place during expansion.
5294 end Array_Type_Declaration;
5296 ------------------------------------------------------
5297 -- Replace_Anonymous_Access_To_Protected_Subprogram --
5298 ------------------------------------------------------
5300 function Replace_Anonymous_Access_To_Protected_Subprogram
5301 (N : Node_Id) return Entity_Id
5303 Loc : constant Source_Ptr := Sloc (N);
5305 Curr_Scope : constant Scope_Stack_Entry :=
5306 Scope_Stack.Table (Scope_Stack.Last);
5308 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
5311 -- Access definition in declaration
5314 -- Object definition or formal definition with an access definition
5317 -- Declaration of anonymous access to subprogram type
5320 -- Original specification in access to subprogram
5325 Set_Is_Internal (Anon);
5328 when N_Component_Declaration |
5329 N_Unconstrained_Array_Definition |
5330 N_Constrained_Array_Definition =>
5331 Comp := Component_Definition (N);
5332 Acc := Access_Definition (Comp);
5334 when N_Discriminant_Specification =>
5335 Comp := Discriminant_Type (N);
5338 when N_Parameter_Specification =>
5339 Comp := Parameter_Type (N);
5342 when N_Access_Function_Definition =>
5343 Comp := Result_Definition (N);
5346 when N_Object_Declaration =>
5347 Comp := Object_Definition (N);
5350 when N_Function_Specification =>
5351 Comp := Result_Definition (N);
5355 raise Program_Error;
5358 Spec := Access_To_Subprogram_Definition (Acc);
5361 Make_Full_Type_Declaration (Loc,
5362 Defining_Identifier => Anon,
5363 Type_Definition => Copy_Separate_Tree (Spec));
5365 Mark_Rewrite_Insertion (Decl);
5367 -- In ASIS mode, analyze the profile on the original node, because
5368 -- the separate copy does not provide enough links to recover the
5369 -- original tree. Analysis is limited to type annotations, within
5370 -- a temporary scope that serves as an anonymous subprogram to collect
5371 -- otherwise useless temporaries and itypes.
5375 Typ : constant Entity_Id := Make_Temporary (Loc, 'S');
5378 if Nkind (Spec) = N_Access_Function_Definition then
5379 Set_Ekind (Typ, E_Function);
5381 Set_Ekind (Typ, E_Procedure);
5384 Set_Parent (Typ, N);
5385 Set_Scope (Typ, Current_Scope);
5388 Process_Formals (Parameter_Specifications (Spec), Spec);
5390 if Nkind (Spec) = N_Access_Function_Definition then
5392 Def : constant Node_Id := Result_Definition (Spec);
5395 -- The result might itself be an anonymous access type, so
5398 if Nkind (Def) = N_Access_Definition then
5399 if Present (Access_To_Subprogram_Definition (Def)) then
5402 Replace_Anonymous_Access_To_Protected_Subprogram
5405 Find_Type (Subtype_Mark (Def));
5418 -- Insert the new declaration in the nearest enclosing scope. If the
5419 -- node is a body and N is its return type, the declaration belongs in
5420 -- the enclosing scope.
5424 if Nkind (P) = N_Subprogram_Body
5425 and then Nkind (N) = N_Function_Specification
5430 while Present (P) and then not Has_Declarations (P) loop
5434 pragma Assert (Present (P));
5436 if Nkind (P) = N_Package_Specification then
5437 Prepend (Decl, Visible_Declarations (P));
5439 Prepend (Decl, Declarations (P));
5442 -- Replace the anonymous type with an occurrence of the new declaration.
5443 -- In all cases the rewritten node does not have the null-exclusion
5444 -- attribute because (if present) it was already inherited by the
5445 -- anonymous entity (Anon). Thus, in case of components we do not
5446 -- inherit this attribute.
5448 if Nkind (N) = N_Parameter_Specification then
5449 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5450 Set_Etype (Defining_Identifier (N), Anon);
5451 Set_Null_Exclusion_Present (N, False);
5453 elsif Nkind (N) = N_Object_Declaration then
5454 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5455 Set_Etype (Defining_Identifier (N), Anon);
5457 elsif Nkind (N) = N_Access_Function_Definition then
5458 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5460 elsif Nkind (N) = N_Function_Specification then
5461 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5462 Set_Etype (Defining_Unit_Name (N), Anon);
5466 Make_Component_Definition (Loc,
5467 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
5470 Mark_Rewrite_Insertion (Comp);
5472 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition) then
5476 -- Temporarily remove the current scope (record or subprogram) from
5477 -- the stack to add the new declarations to the enclosing scope.
5479 Scope_Stack.Decrement_Last;
5481 Set_Is_Itype (Anon);
5482 Scope_Stack.Append (Curr_Scope);
5485 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
5486 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
5488 end Replace_Anonymous_Access_To_Protected_Subprogram;
5490 -------------------------------
5491 -- Build_Derived_Access_Type --
5492 -------------------------------
5494 procedure Build_Derived_Access_Type
5496 Parent_Type : Entity_Id;
5497 Derived_Type : Entity_Id)
5499 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
5501 Desig_Type : Entity_Id;
5503 Discr_Con_Elist : Elist_Id;
5504 Discr_Con_El : Elmt_Id;
5508 -- Set the designated type so it is available in case this is an access
5509 -- to a self-referential type, e.g. a standard list type with a next
5510 -- pointer. Will be reset after subtype is built.
5512 Set_Directly_Designated_Type
5513 (Derived_Type, Designated_Type (Parent_Type));
5515 Subt := Process_Subtype (S, N);
5517 if Nkind (S) /= N_Subtype_Indication
5518 and then Subt /= Base_Type (Subt)
5520 Set_Ekind (Derived_Type, E_Access_Subtype);
5523 if Ekind (Derived_Type) = E_Access_Subtype then
5525 Pbase : constant Entity_Id := Base_Type (Parent_Type);
5526 Ibase : constant Entity_Id :=
5527 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
5528 Svg_Chars : constant Name_Id := Chars (Ibase);
5529 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
5532 Copy_Node (Pbase, Ibase);
5534 Set_Chars (Ibase, Svg_Chars);
5535 Set_Next_Entity (Ibase, Svg_Next_E);
5536 Set_Sloc (Ibase, Sloc (Derived_Type));
5537 Set_Scope (Ibase, Scope (Derived_Type));
5538 Set_Freeze_Node (Ibase, Empty);
5539 Set_Is_Frozen (Ibase, False);
5540 Set_Comes_From_Source (Ibase, False);
5541 Set_Is_First_Subtype (Ibase, False);
5543 Set_Etype (Ibase, Pbase);
5544 Set_Etype (Derived_Type, Ibase);
5548 Set_Directly_Designated_Type
5549 (Derived_Type, Designated_Type (Subt));
5551 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
5552 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
5553 Set_Size_Info (Derived_Type, Parent_Type);
5554 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
5555 Set_Depends_On_Private (Derived_Type,
5556 Has_Private_Component (Derived_Type));
5557 Conditional_Delay (Derived_Type, Subt);
5559 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
5560 -- that it is not redundant.
5562 if Null_Exclusion_Present (Type_Definition (N)) then
5563 Set_Can_Never_Be_Null (Derived_Type);
5565 -- What is with the "AND THEN FALSE" here ???
5567 if Can_Never_Be_Null (Parent_Type)
5571 ("`NOT NULL` not allowed (& already excludes null)",
5575 elsif Can_Never_Be_Null (Parent_Type) then
5576 Set_Can_Never_Be_Null (Derived_Type);
5579 -- Note: we do not copy the Storage_Size_Variable, since we always go to
5580 -- the root type for this information.
5582 -- Apply range checks to discriminants for derived record case
5583 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
5585 Desig_Type := Designated_Type (Derived_Type);
5586 if Is_Composite_Type (Desig_Type)
5587 and then (not Is_Array_Type (Desig_Type))
5588 and then Has_Discriminants (Desig_Type)
5589 and then Base_Type (Desig_Type) /= Desig_Type
5591 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
5592 Discr_Con_El := First_Elmt (Discr_Con_Elist);
5594 Discr := First_Discriminant (Base_Type (Desig_Type));
5595 while Present (Discr_Con_El) loop
5596 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
5597 Next_Elmt (Discr_Con_El);
5598 Next_Discriminant (Discr);
5601 end Build_Derived_Access_Type;
5603 ------------------------------
5604 -- Build_Derived_Array_Type --
5605 ------------------------------
5607 procedure Build_Derived_Array_Type
5609 Parent_Type : Entity_Id;
5610 Derived_Type : Entity_Id)
5612 Loc : constant Source_Ptr := Sloc (N);
5613 Tdef : constant Node_Id := Type_Definition (N);
5614 Indic : constant Node_Id := Subtype_Indication (Tdef);
5615 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5616 Implicit_Base : Entity_Id;
5617 New_Indic : Node_Id;
5619 procedure Make_Implicit_Base;
5620 -- If the parent subtype is constrained, the derived type is a subtype
5621 -- of an implicit base type derived from the parent base.
5623 ------------------------
5624 -- Make_Implicit_Base --
5625 ------------------------
5627 procedure Make_Implicit_Base is
5630 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5632 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5633 Set_Etype (Implicit_Base, Parent_Base);
5635 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
5636 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
5638 Set_Has_Delayed_Freeze (Implicit_Base, True);
5639 end Make_Implicit_Base;
5641 -- Start of processing for Build_Derived_Array_Type
5644 if not Is_Constrained (Parent_Type) then
5645 if Nkind (Indic) /= N_Subtype_Indication then
5646 Set_Ekind (Derived_Type, E_Array_Type);
5648 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5649 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
5651 Set_Has_Delayed_Freeze (Derived_Type, True);
5655 Set_Etype (Derived_Type, Implicit_Base);
5658 Make_Subtype_Declaration (Loc,
5659 Defining_Identifier => Derived_Type,
5660 Subtype_Indication =>
5661 Make_Subtype_Indication (Loc,
5662 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
5663 Constraint => Constraint (Indic)));
5665 Rewrite (N, New_Indic);
5670 if Nkind (Indic) /= N_Subtype_Indication then
5673 Set_Ekind (Derived_Type, Ekind (Parent_Type));
5674 Set_Etype (Derived_Type, Implicit_Base);
5675 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5678 Error_Msg_N ("illegal constraint on constrained type", Indic);
5682 -- If parent type is not a derived type itself, and is declared in
5683 -- closed scope (e.g. a subprogram), then we must explicitly introduce
5684 -- the new type's concatenation operator since Derive_Subprograms
5685 -- will not inherit the parent's operator. If the parent type is
5686 -- unconstrained, the operator is of the unconstrained base type.
5688 if Number_Dimensions (Parent_Type) = 1
5689 and then not Is_Limited_Type (Parent_Type)
5690 and then not Is_Derived_Type (Parent_Type)
5691 and then not Is_Package_Or_Generic_Package
5692 (Scope (Base_Type (Parent_Type)))
5694 if not Is_Constrained (Parent_Type)
5695 and then Is_Constrained (Derived_Type)
5697 New_Concatenation_Op (Implicit_Base);
5699 New_Concatenation_Op (Derived_Type);
5702 end Build_Derived_Array_Type;
5704 -----------------------------------
5705 -- Build_Derived_Concurrent_Type --
5706 -----------------------------------
5708 procedure Build_Derived_Concurrent_Type
5710 Parent_Type : Entity_Id;
5711 Derived_Type : Entity_Id)
5713 Loc : constant Source_Ptr := Sloc (N);
5715 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
5716 Corr_Decl : Node_Id;
5717 Corr_Decl_Needed : Boolean;
5718 -- If the derived type has fewer discriminants than its parent, the
5719 -- corresponding record is also a derived type, in order to account for
5720 -- the bound discriminants. We create a full type declaration for it in
5723 Constraint_Present : constant Boolean :=
5724 Nkind (Subtype_Indication (Type_Definition (N))) =
5725 N_Subtype_Indication;
5727 D_Constraint : Node_Id;
5728 New_Constraint : Elist_Id;
5729 Old_Disc : Entity_Id;
5730 New_Disc : Entity_Id;
5734 Set_Stored_Constraint (Derived_Type, No_Elist);
5735 Corr_Decl_Needed := False;
5738 if Present (Discriminant_Specifications (N))
5739 and then Constraint_Present
5741 Old_Disc := First_Discriminant (Parent_Type);
5742 New_Disc := First (Discriminant_Specifications (N));
5743 while Present (New_Disc) and then Present (Old_Disc) loop
5744 Next_Discriminant (Old_Disc);
5749 if Present (Old_Disc) and then Expander_Active then
5751 -- The new type has fewer discriminants, so we need to create a new
5752 -- corresponding record, which is derived from the corresponding
5753 -- record of the parent, and has a stored constraint that captures
5754 -- the values of the discriminant constraints. The corresponding
5755 -- record is needed only if expander is active and code generation is
5758 -- The type declaration for the derived corresponding record has the
5759 -- same discriminant part and constraints as the current declaration.
5760 -- Copy the unanalyzed tree to build declaration.
5762 Corr_Decl_Needed := True;
5763 New_N := Copy_Separate_Tree (N);
5766 Make_Full_Type_Declaration (Loc,
5767 Defining_Identifier => Corr_Record,
5768 Discriminant_Specifications =>
5769 Discriminant_Specifications (New_N),
5771 Make_Derived_Type_Definition (Loc,
5772 Subtype_Indication =>
5773 Make_Subtype_Indication (Loc,
5776 (Corresponding_Record_Type (Parent_Type), Loc),
5779 (Subtype_Indication (Type_Definition (New_N))))));
5782 -- Copy Storage_Size and Relative_Deadline variables if task case
5784 if Is_Task_Type (Parent_Type) then
5785 Set_Storage_Size_Variable (Derived_Type,
5786 Storage_Size_Variable (Parent_Type));
5787 Set_Relative_Deadline_Variable (Derived_Type,
5788 Relative_Deadline_Variable (Parent_Type));
5791 if Present (Discriminant_Specifications (N)) then
5792 Push_Scope (Derived_Type);
5793 Check_Or_Process_Discriminants (N, Derived_Type);
5795 if Constraint_Present then
5797 Expand_To_Stored_Constraint
5799 Build_Discriminant_Constraints
5801 Subtype_Indication (Type_Definition (N)), True));
5806 elsif Constraint_Present then
5808 -- Build constrained subtype, copying the constraint, and derive
5809 -- from it to create a derived constrained type.
5812 Loc : constant Source_Ptr := Sloc (N);
5813 Anon : constant Entity_Id :=
5814 Make_Defining_Identifier (Loc,
5815 Chars => New_External_Name (Chars (Derived_Type), 'T'));
5820 Make_Subtype_Declaration (Loc,
5821 Defining_Identifier => Anon,
5822 Subtype_Indication =>
5823 New_Copy_Tree (Subtype_Indication (Type_Definition (N))));
5824 Insert_Before (N, Decl);
5827 Rewrite (Subtype_Indication (Type_Definition (N)),
5828 New_Occurrence_Of (Anon, Loc));
5829 Set_Analyzed (Derived_Type, False);
5835 -- By default, operations and private data are inherited from parent.
5836 -- However, in the presence of bound discriminants, a new corresponding
5837 -- record will be created, see below.
5839 Set_Has_Discriminants
5840 (Derived_Type, Has_Discriminants (Parent_Type));
5841 Set_Corresponding_Record_Type
5842 (Derived_Type, Corresponding_Record_Type (Parent_Type));
5844 -- Is_Constrained is set according the parent subtype, but is set to
5845 -- False if the derived type is declared with new discriminants.
5849 (Is_Constrained (Parent_Type) or else Constraint_Present)
5850 and then not Present (Discriminant_Specifications (N)));
5852 if Constraint_Present then
5853 if not Has_Discriminants (Parent_Type) then
5854 Error_Msg_N ("untagged parent must have discriminants", N);
5856 elsif Present (Discriminant_Specifications (N)) then
5858 -- Verify that new discriminants are used to constrain old ones
5863 (Constraint (Subtype_Indication (Type_Definition (N)))));
5865 Old_Disc := First_Discriminant (Parent_Type);
5867 while Present (D_Constraint) loop
5868 if Nkind (D_Constraint) /= N_Discriminant_Association then
5870 -- Positional constraint. If it is a reference to a new
5871 -- discriminant, it constrains the corresponding old one.
5873 if Nkind (D_Constraint) = N_Identifier then
5874 New_Disc := First_Discriminant (Derived_Type);
5875 while Present (New_Disc) loop
5876 exit when Chars (New_Disc) = Chars (D_Constraint);
5877 Next_Discriminant (New_Disc);
5880 if Present (New_Disc) then
5881 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
5885 Next_Discriminant (Old_Disc);
5887 -- if this is a named constraint, search by name for the old
5888 -- discriminants constrained by the new one.
5890 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
5892 -- Find new discriminant with that name
5894 New_Disc := First_Discriminant (Derived_Type);
5895 while Present (New_Disc) loop
5897 Chars (New_Disc) = Chars (Expression (D_Constraint));
5898 Next_Discriminant (New_Disc);
5901 if Present (New_Disc) then
5903 -- Verify that new discriminant renames some discriminant
5904 -- of the parent type, and associate the new discriminant
5905 -- with one or more old ones that it renames.
5911 Selector := First (Selector_Names (D_Constraint));
5912 while Present (Selector) loop
5913 Old_Disc := First_Discriminant (Parent_Type);
5914 while Present (Old_Disc) loop
5915 exit when Chars (Old_Disc) = Chars (Selector);
5916 Next_Discriminant (Old_Disc);
5919 if Present (Old_Disc) then
5920 Set_Corresponding_Discriminant
5921 (New_Disc, Old_Disc);
5930 Next (D_Constraint);
5933 New_Disc := First_Discriminant (Derived_Type);
5934 while Present (New_Disc) loop
5935 if No (Corresponding_Discriminant (New_Disc)) then
5937 ("new discriminant& must constrain old one", N, New_Disc);
5940 Subtypes_Statically_Compatible
5942 Etype (Corresponding_Discriminant (New_Disc)))
5945 ("& not statically compatible with parent discriminant",
5949 Next_Discriminant (New_Disc);
5953 elsif Present (Discriminant_Specifications (N)) then
5955 ("missing discriminant constraint in untagged derivation", N);
5958 -- The entity chain of the derived type includes the new discriminants
5959 -- but shares operations with the parent.
5961 if Present (Discriminant_Specifications (N)) then
5962 Old_Disc := First_Discriminant (Parent_Type);
5963 while Present (Old_Disc) loop
5964 if No (Next_Entity (Old_Disc))
5965 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
5968 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
5972 Next_Discriminant (Old_Disc);
5976 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
5977 if Has_Discriminants (Parent_Type) then
5978 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5979 Set_Discriminant_Constraint (
5980 Derived_Type, Discriminant_Constraint (Parent_Type));
5984 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
5986 Set_Has_Completion (Derived_Type);
5988 if Corr_Decl_Needed then
5989 Set_Stored_Constraint (Derived_Type, New_Constraint);
5990 Insert_After (N, Corr_Decl);
5991 Analyze (Corr_Decl);
5992 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
5994 end Build_Derived_Concurrent_Type;
5996 ------------------------------------
5997 -- Build_Derived_Enumeration_Type --
5998 ------------------------------------
6000 procedure Build_Derived_Enumeration_Type
6002 Parent_Type : Entity_Id;
6003 Derived_Type : Entity_Id)
6005 Loc : constant Source_Ptr := Sloc (N);
6006 Def : constant Node_Id := Type_Definition (N);
6007 Indic : constant Node_Id := Subtype_Indication (Def);
6008 Implicit_Base : Entity_Id;
6009 Literal : Entity_Id;
6010 New_Lit : Entity_Id;
6011 Literals_List : List_Id;
6012 Type_Decl : Node_Id;
6014 Rang_Expr : Node_Id;
6017 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
6018 -- not have explicit literals lists we need to process types derived
6019 -- from them specially. This is handled by Derived_Standard_Character.
6020 -- If the parent type is a generic type, there are no literals either,
6021 -- and we construct the same skeletal representation as for the generic
6024 if Is_Standard_Character_Type (Parent_Type) then
6025 Derived_Standard_Character (N, Parent_Type, Derived_Type);
6027 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
6033 if Nkind (Indic) /= N_Subtype_Indication then
6035 Make_Attribute_Reference (Loc,
6036 Attribute_Name => Name_First,
6037 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6038 Set_Etype (Lo, Derived_Type);
6041 Make_Attribute_Reference (Loc,
6042 Attribute_Name => Name_Last,
6043 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6044 Set_Etype (Hi, Derived_Type);
6046 Set_Scalar_Range (Derived_Type,
6052 -- Analyze subtype indication and verify compatibility
6053 -- with parent type.
6055 if Base_Type (Process_Subtype (Indic, N)) /=
6056 Base_Type (Parent_Type)
6059 ("illegal constraint for formal discrete type", N);
6065 -- If a constraint is present, analyze the bounds to catch
6066 -- premature usage of the derived literals.
6068 if Nkind (Indic) = N_Subtype_Indication
6069 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
6071 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
6072 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
6075 -- Introduce an implicit base type for the derived type even if there
6076 -- is no constraint attached to it, since this seems closer to the
6077 -- Ada semantics. Build a full type declaration tree for the derived
6078 -- type using the implicit base type as the defining identifier. The
6079 -- build a subtype declaration tree which applies the constraint (if
6080 -- any) have it replace the derived type declaration.
6082 Literal := First_Literal (Parent_Type);
6083 Literals_List := New_List;
6084 while Present (Literal)
6085 and then Ekind (Literal) = E_Enumeration_Literal
6087 -- Literals of the derived type have the same representation as
6088 -- those of the parent type, but this representation can be
6089 -- overridden by an explicit representation clause. Indicate
6090 -- that there is no explicit representation given yet. These
6091 -- derived literals are implicit operations of the new type,
6092 -- and can be overridden by explicit ones.
6094 if Nkind (Literal) = N_Defining_Character_Literal then
6096 Make_Defining_Character_Literal (Loc, Chars (Literal));
6098 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
6101 Set_Ekind (New_Lit, E_Enumeration_Literal);
6102 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
6103 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
6104 Set_Enumeration_Rep_Expr (New_Lit, Empty);
6105 Set_Alias (New_Lit, Literal);
6106 Set_Is_Known_Valid (New_Lit, True);
6108 Append (New_Lit, Literals_List);
6109 Next_Literal (Literal);
6113 Make_Defining_Identifier (Sloc (Derived_Type),
6114 Chars => New_External_Name (Chars (Derived_Type), 'B'));
6116 -- Indicate the proper nature of the derived type. This must be done
6117 -- before analysis of the literals, to recognize cases when a literal
6118 -- may be hidden by a previous explicit function definition (cf.
6121 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
6122 Set_Etype (Derived_Type, Implicit_Base);
6125 Make_Full_Type_Declaration (Loc,
6126 Defining_Identifier => Implicit_Base,
6127 Discriminant_Specifications => No_List,
6129 Make_Enumeration_Type_Definition (Loc, Literals_List));
6131 Mark_Rewrite_Insertion (Type_Decl);
6132 Insert_Before (N, Type_Decl);
6133 Analyze (Type_Decl);
6135 -- After the implicit base is analyzed its Etype needs to be changed
6136 -- to reflect the fact that it is derived from the parent type which
6137 -- was ignored during analysis. We also set the size at this point.
6139 Set_Etype (Implicit_Base, Parent_Type);
6141 Set_Size_Info (Implicit_Base, Parent_Type);
6142 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
6143 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
6145 -- Copy other flags from parent type
6147 Set_Has_Non_Standard_Rep
6148 (Implicit_Base, Has_Non_Standard_Rep
6150 Set_Has_Pragma_Ordered
6151 (Implicit_Base, Has_Pragma_Ordered
6153 Set_Has_Delayed_Freeze (Implicit_Base);
6155 -- Process the subtype indication including a validation check on the
6156 -- constraint, if any. If a constraint is given, its bounds must be
6157 -- implicitly converted to the new type.
6159 if Nkind (Indic) = N_Subtype_Indication then
6161 R : constant Node_Id :=
6162 Range_Expression (Constraint (Indic));
6165 if Nkind (R) = N_Range then
6166 Hi := Build_Scalar_Bound
6167 (High_Bound (R), Parent_Type, Implicit_Base);
6168 Lo := Build_Scalar_Bound
6169 (Low_Bound (R), Parent_Type, Implicit_Base);
6172 -- Constraint is a Range attribute. Replace with explicit
6173 -- mention of the bounds of the prefix, which must be a
6176 Analyze (Prefix (R));
6178 Convert_To (Implicit_Base,
6179 Make_Attribute_Reference (Loc,
6180 Attribute_Name => Name_Last,
6182 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6185 Convert_To (Implicit_Base,
6186 Make_Attribute_Reference (Loc,
6187 Attribute_Name => Name_First,
6189 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6196 (Type_High_Bound (Parent_Type),
6197 Parent_Type, Implicit_Base);
6200 (Type_Low_Bound (Parent_Type),
6201 Parent_Type, Implicit_Base);
6209 -- If we constructed a default range for the case where no range
6210 -- was given, then the expressions in the range must not freeze
6211 -- since they do not correspond to expressions in the source.
6213 if Nkind (Indic) /= N_Subtype_Indication then
6214 Set_Must_Not_Freeze (Lo);
6215 Set_Must_Not_Freeze (Hi);
6216 Set_Must_Not_Freeze (Rang_Expr);
6220 Make_Subtype_Declaration (Loc,
6221 Defining_Identifier => Derived_Type,
6222 Subtype_Indication =>
6223 Make_Subtype_Indication (Loc,
6224 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6226 Make_Range_Constraint (Loc,
6227 Range_Expression => Rang_Expr))));
6231 -- Apply a range check. Since this range expression doesn't have an
6232 -- Etype, we have to specifically pass the Source_Typ parameter. Is
6235 if Nkind (Indic) = N_Subtype_Indication then
6236 Apply_Range_Check (Range_Expression (Constraint (Indic)),
6238 Source_Typ => Entity (Subtype_Mark (Indic)));
6241 end Build_Derived_Enumeration_Type;
6243 --------------------------------
6244 -- Build_Derived_Numeric_Type --
6245 --------------------------------
6247 procedure Build_Derived_Numeric_Type
6249 Parent_Type : Entity_Id;
6250 Derived_Type : Entity_Id)
6252 Loc : constant Source_Ptr := Sloc (N);
6253 Tdef : constant Node_Id := Type_Definition (N);
6254 Indic : constant Node_Id := Subtype_Indication (Tdef);
6255 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6256 No_Constraint : constant Boolean := Nkind (Indic) /=
6257 N_Subtype_Indication;
6258 Implicit_Base : Entity_Id;
6264 -- Process the subtype indication including a validation check on
6265 -- the constraint if any.
6267 Discard_Node (Process_Subtype (Indic, N));
6269 -- Introduce an implicit base type for the derived type even if there
6270 -- is no constraint attached to it, since this seems closer to the Ada
6274 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6276 Set_Etype (Implicit_Base, Parent_Base);
6277 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6278 Set_Size_Info (Implicit_Base, Parent_Base);
6279 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
6280 Set_Parent (Implicit_Base, Parent (Derived_Type));
6281 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
6283 -- Set RM Size for discrete type or decimal fixed-point type
6284 -- Ordinary fixed-point is excluded, why???
6286 if Is_Discrete_Type (Parent_Base)
6287 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
6289 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
6292 Set_Has_Delayed_Freeze (Implicit_Base);
6294 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
6295 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
6297 Set_Scalar_Range (Implicit_Base,
6302 if Has_Infinities (Parent_Base) then
6303 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
6306 -- The Derived_Type, which is the entity of the declaration, is a
6307 -- subtype of the implicit base. Its Ekind is a subtype, even in the
6308 -- absence of an explicit constraint.
6310 Set_Etype (Derived_Type, Implicit_Base);
6312 -- If we did not have a constraint, then the Ekind is set from the
6313 -- parent type (otherwise Process_Subtype has set the bounds)
6315 if No_Constraint then
6316 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
6319 -- If we did not have a range constraint, then set the range from the
6320 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
6323 or else not Has_Range_Constraint (Indic)
6325 Set_Scalar_Range (Derived_Type,
6327 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
6328 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
6329 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6331 if Has_Infinities (Parent_Type) then
6332 Set_Includes_Infinities (Scalar_Range (Derived_Type));
6335 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
6338 Set_Is_Descendent_Of_Address (Derived_Type,
6339 Is_Descendent_Of_Address (Parent_Type));
6340 Set_Is_Descendent_Of_Address (Implicit_Base,
6341 Is_Descendent_Of_Address (Parent_Type));
6343 -- Set remaining type-specific fields, depending on numeric type
6345 if Is_Modular_Integer_Type (Parent_Type) then
6346 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
6348 Set_Non_Binary_Modulus
6349 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
6352 (Implicit_Base, Is_Known_Valid (Parent_Base));
6354 elsif Is_Floating_Point_Type (Parent_Type) then
6356 -- Digits of base type is always copied from the digits value of
6357 -- the parent base type, but the digits of the derived type will
6358 -- already have been set if there was a constraint present.
6360 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6361 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
6363 if No_Constraint then
6364 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
6367 elsif Is_Fixed_Point_Type (Parent_Type) then
6369 -- Small of base type and derived type are always copied from the
6370 -- parent base type, since smalls never change. The delta of the
6371 -- base type is also copied from the parent base type. However the
6372 -- delta of the derived type will have been set already if a
6373 -- constraint was present.
6375 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
6376 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
6377 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
6379 if No_Constraint then
6380 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
6383 -- The scale and machine radix in the decimal case are always
6384 -- copied from the parent base type.
6386 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
6387 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
6388 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
6390 Set_Machine_Radix_10
6391 (Derived_Type, Machine_Radix_10 (Parent_Base));
6392 Set_Machine_Radix_10
6393 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6395 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6397 if No_Constraint then
6398 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6401 -- the analysis of the subtype_indication sets the
6402 -- digits value of the derived type.
6409 if Is_Integer_Type (Parent_Type) then
6410 Set_Has_Shift_Operator
6411 (Implicit_Base, Has_Shift_Operator (Parent_Type));
6414 -- The type of the bounds is that of the parent type, and they
6415 -- must be converted to the derived type.
6417 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
6419 -- The implicit_base should be frozen when the derived type is frozen,
6420 -- but note that it is used in the conversions of the bounds. For fixed
6421 -- types we delay the determination of the bounds until the proper
6422 -- freezing point. For other numeric types this is rejected by GCC, for
6423 -- reasons that are currently unclear (???), so we choose to freeze the
6424 -- implicit base now. In the case of integers and floating point types
6425 -- this is harmless because subsequent representation clauses cannot
6426 -- affect anything, but it is still baffling that we cannot use the
6427 -- same mechanism for all derived numeric types.
6429 -- There is a further complication: actually some representation
6430 -- clauses can affect the implicit base type. For example, attribute
6431 -- definition clauses for stream-oriented attributes need to set the
6432 -- corresponding TSS entries on the base type, and this normally
6433 -- cannot be done after the base type is frozen, so the circuitry in
6434 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility
6435 -- and not use Set_TSS in this case.
6437 -- There are also consequences for the case of delayed representation
6438 -- aspects for some cases. For example, a Size aspect is delayed and
6439 -- should not be evaluated to the freeze point. This early freezing
6440 -- means that the size attribute evaluation happens too early???
6442 if Is_Fixed_Point_Type (Parent_Type) then
6443 Conditional_Delay (Implicit_Base, Parent_Type);
6445 Freeze_Before (N, Implicit_Base);
6447 end Build_Derived_Numeric_Type;
6449 --------------------------------
6450 -- Build_Derived_Private_Type --
6451 --------------------------------
6453 procedure Build_Derived_Private_Type
6455 Parent_Type : Entity_Id;
6456 Derived_Type : Entity_Id;
6457 Is_Completion : Boolean;
6458 Derive_Subps : Boolean := True)
6460 Loc : constant Source_Ptr := Sloc (N);
6461 Der_Base : Entity_Id;
6463 Full_Decl : Node_Id := Empty;
6464 Full_Der : Entity_Id;
6466 Last_Discr : Entity_Id;
6467 Par_Scope : constant Entity_Id := Scope (Base_Type (Parent_Type));
6468 Swapped : Boolean := False;
6470 procedure Copy_And_Build;
6471 -- Copy derived type declaration, replace parent with its full view,
6472 -- and analyze new declaration.
6474 --------------------
6475 -- Copy_And_Build --
6476 --------------------
6478 procedure Copy_And_Build is
6482 if Ekind (Parent_Type) in Record_Kind
6484 (Ekind (Parent_Type) in Enumeration_Kind
6485 and then not Is_Standard_Character_Type (Parent_Type)
6486 and then not Is_Generic_Type (Root_Type (Parent_Type)))
6488 Full_N := New_Copy_Tree (N);
6489 Insert_After (N, Full_N);
6490 Build_Derived_Type (
6491 Full_N, Parent_Type, Full_Der, True, Derive_Subps => False);
6494 Build_Derived_Type (
6495 N, Parent_Type, Full_Der, True, Derive_Subps => False);
6499 -- Start of processing for Build_Derived_Private_Type
6502 if Is_Tagged_Type (Parent_Type) then
6503 Full_P := Full_View (Parent_Type);
6505 -- A type extension of a type with unknown discriminants is an
6506 -- indefinite type that the back-end cannot handle directly.
6507 -- We treat it as a private type, and build a completion that is
6508 -- derived from the full view of the parent, and hopefully has
6509 -- known discriminants.
6511 -- If the full view of the parent type has an underlying record view,
6512 -- use it to generate the underlying record view of this derived type
6513 -- (required for chains of derivations with unknown discriminants).
6515 -- Minor optimization: we avoid the generation of useless underlying
6516 -- record view entities if the private type declaration has unknown
6517 -- discriminants but its corresponding full view has no
6520 if Has_Unknown_Discriminants (Parent_Type)
6521 and then Present (Full_P)
6522 and then (Has_Discriminants (Full_P)
6523 or else Present (Underlying_Record_View (Full_P)))
6524 and then not In_Open_Scopes (Par_Scope)
6525 and then Expander_Active
6528 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
6529 New_Ext : constant Node_Id :=
6531 (Record_Extension_Part (Type_Definition (N)));
6535 Build_Derived_Record_Type
6536 (N, Parent_Type, Derived_Type, Derive_Subps);
6538 -- Build anonymous completion, as a derivation from the full
6539 -- view of the parent. This is not a completion in the usual
6540 -- sense, because the current type is not private.
6543 Make_Full_Type_Declaration (Loc,
6544 Defining_Identifier => Full_Der,
6546 Make_Derived_Type_Definition (Loc,
6547 Subtype_Indication =>
6549 (Subtype_Indication (Type_Definition (N))),
6550 Record_Extension_Part => New_Ext));
6552 -- If the parent type has an underlying record view, use it
6553 -- here to build the new underlying record view.
6555 if Present (Underlying_Record_View (Full_P)) then
6557 (Nkind (Subtype_Indication (Type_Definition (Decl)))
6559 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
6560 Underlying_Record_View (Full_P));
6563 Install_Private_Declarations (Par_Scope);
6564 Install_Visible_Declarations (Par_Scope);
6565 Insert_Before (N, Decl);
6567 -- Mark entity as an underlying record view before analysis,
6568 -- to avoid generating the list of its primitive operations
6569 -- (which is not really required for this entity) and thus
6570 -- prevent spurious errors associated with missing overriding
6571 -- of abstract primitives (overridden only for Derived_Type).
6573 Set_Ekind (Full_Der, E_Record_Type);
6574 Set_Is_Underlying_Record_View (Full_Der);
6578 pragma Assert (Has_Discriminants (Full_Der)
6579 and then not Has_Unknown_Discriminants (Full_Der));
6581 Uninstall_Declarations (Par_Scope);
6583 -- Freeze the underlying record view, to prevent generation of
6584 -- useless dispatching information, which is simply shared with
6585 -- the real derived type.
6587 Set_Is_Frozen (Full_Der);
6589 -- Set up links between real entity and underlying record view
6591 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
6592 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
6595 -- If discriminants are known, build derived record
6598 Build_Derived_Record_Type
6599 (N, Parent_Type, Derived_Type, Derive_Subps);
6604 elsif Has_Discriminants (Parent_Type) then
6605 if Present (Full_View (Parent_Type)) then
6606 if not Is_Completion then
6608 -- Copy declaration for subsequent analysis, to provide a
6609 -- completion for what is a private declaration. Indicate that
6610 -- the full type is internally generated.
6612 Full_Decl := New_Copy_Tree (N);
6613 Full_Der := New_Copy (Derived_Type);
6614 Set_Comes_From_Source (Full_Decl, False);
6615 Set_Comes_From_Source (Full_Der, False);
6616 Set_Parent (Full_Der, Full_Decl);
6618 Insert_After (N, Full_Decl);
6621 -- If this is a completion, the full view being built is itself
6622 -- private. We build a subtype of the parent with the same
6623 -- constraints as this full view, to convey to the back end the
6624 -- constrained components and the size of this subtype. If the
6625 -- parent is constrained, its full view can serve as the
6626 -- underlying full view of the derived type.
6628 if No (Discriminant_Specifications (N)) then
6629 if Nkind (Subtype_Indication (Type_Definition (N))) =
6630 N_Subtype_Indication
6632 Build_Underlying_Full_View (N, Derived_Type, Parent_Type);
6634 elsif Is_Constrained (Full_View (Parent_Type)) then
6635 Set_Underlying_Full_View
6636 (Derived_Type, Full_View (Parent_Type));
6640 -- If there are new discriminants, the parent subtype is
6641 -- constrained by them, but it is not clear how to build
6642 -- the Underlying_Full_View in this case???
6649 -- Build partial view of derived type from partial view of parent
6651 Build_Derived_Record_Type
6652 (N, Parent_Type, Derived_Type, Derive_Subps);
6654 if Present (Full_View (Parent_Type)) and then not Is_Completion then
6655 if not In_Open_Scopes (Par_Scope)
6656 or else not In_Same_Source_Unit (N, Parent_Type)
6658 -- Swap partial and full views temporarily
6660 Install_Private_Declarations (Par_Scope);
6661 Install_Visible_Declarations (Par_Scope);
6665 -- Build full view of derived type from full view of parent which
6666 -- is now installed. Subprograms have been derived on the partial
6667 -- view, the completion does not derive them anew.
6669 if not Is_Tagged_Type (Parent_Type) then
6671 -- If the parent is itself derived from another private type,
6672 -- installing the private declarations has not affected its
6673 -- privacy status, so use its own full view explicitly.
6675 if Is_Private_Type (Parent_Type) then
6676 Build_Derived_Record_Type
6677 (Full_Decl, Full_View (Parent_Type), Full_Der, False);
6679 Build_Derived_Record_Type
6680 (Full_Decl, Parent_Type, Full_Der, False);
6684 -- If full view of parent is tagged, the completion inherits
6685 -- the proper primitive operations.
6687 Set_Defining_Identifier (Full_Decl, Full_Der);
6688 Build_Derived_Record_Type
6689 (Full_Decl, Parent_Type, Full_Der, Derive_Subps);
6692 -- The full declaration has been introduced into the tree and
6693 -- processed in the step above. It should not be analyzed again
6694 -- (when encountered later in the current list of declarations)
6695 -- to prevent spurious name conflicts. The full entity remains
6698 Set_Analyzed (Full_Decl);
6701 Uninstall_Declarations (Par_Scope);
6703 if In_Open_Scopes (Par_Scope) then
6704 Install_Visible_Declarations (Par_Scope);
6708 Der_Base := Base_Type (Derived_Type);
6709 Set_Full_View (Derived_Type, Full_Der);
6710 Set_Full_View (Der_Base, Base_Type (Full_Der));
6712 -- Copy the discriminant list from full view to the partial views
6713 -- (base type and its subtype). Gigi requires that the partial and
6714 -- full views have the same discriminants.
6716 -- Note that since the partial view is pointing to discriminants
6717 -- in the full view, their scope will be that of the full view.
6718 -- This might cause some front end problems and need adjustment???
6720 Discr := First_Discriminant (Base_Type (Full_Der));
6721 Set_First_Entity (Der_Base, Discr);
6724 Last_Discr := Discr;
6725 Next_Discriminant (Discr);
6726 exit when No (Discr);
6729 Set_Last_Entity (Der_Base, Last_Discr);
6731 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
6732 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
6733 Set_Stored_Constraint (Full_Der, Stored_Constraint (Derived_Type));
6736 -- If this is a completion, the derived type stays private and
6737 -- there is no need to create a further full view, except in the
6738 -- unusual case when the derivation is nested within a child unit,
6744 elsif Present (Full_View (Parent_Type))
6745 and then Has_Discriminants (Full_View (Parent_Type))
6747 if Has_Unknown_Discriminants (Parent_Type)
6748 and then Nkind (Subtype_Indication (Type_Definition (N))) =
6749 N_Subtype_Indication
6752 ("cannot constrain type with unknown discriminants",
6753 Subtype_Indication (Type_Definition (N)));
6757 -- If full view of parent is a record type, build full view as a
6758 -- derivation from the parent's full view. Partial view remains
6759 -- private. For code generation and linking, the full view must have
6760 -- the same public status as the partial one. This full view is only
6761 -- needed if the parent type is in an enclosing scope, so that the
6762 -- full view may actually become visible, e.g. in a child unit. This
6763 -- is both more efficient, and avoids order of freezing problems with
6764 -- the added entities.
6766 if not Is_Private_Type (Full_View (Parent_Type))
6767 and then (In_Open_Scopes (Scope (Parent_Type)))
6770 Make_Defining_Identifier (Sloc (Derived_Type),
6771 Chars => Chars (Derived_Type));
6773 Set_Is_Itype (Full_Der);
6774 Set_Has_Private_Declaration (Full_Der);
6775 Set_Has_Private_Declaration (Derived_Type);
6776 Set_Associated_Node_For_Itype (Full_Der, N);
6777 Set_Parent (Full_Der, Parent (Derived_Type));
6778 Set_Full_View (Derived_Type, Full_Der);
6779 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
6780 Full_P := Full_View (Parent_Type);
6781 Exchange_Declarations (Parent_Type);
6783 Exchange_Declarations (Full_P);
6786 Build_Derived_Record_Type
6787 (N, Full_View (Parent_Type), Derived_Type,
6788 Derive_Subps => False);
6790 -- Except in the context of the full view of the parent, there
6791 -- are no non-extension aggregates for the derived type.
6793 Set_Has_Private_Ancestor (Derived_Type);
6796 -- In any case, the primitive operations are inherited from the
6797 -- parent type, not from the internal full view.
6799 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
6801 if Derive_Subps then
6802 Derive_Subprograms (Parent_Type, Derived_Type);
6806 -- Untagged type, No discriminants on either view
6808 if Nkind (Subtype_Indication (Type_Definition (N))) =
6809 N_Subtype_Indication
6812 ("illegal constraint on type without discriminants", N);
6815 if Present (Discriminant_Specifications (N))
6816 and then Present (Full_View (Parent_Type))
6817 and then not Is_Tagged_Type (Full_View (Parent_Type))
6819 Error_Msg_N ("cannot add discriminants to untagged type", N);
6822 Set_Stored_Constraint (Derived_Type, No_Elist);
6823 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6824 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
6825 Set_Has_Controlled_Component
6826 (Derived_Type, Has_Controlled_Component
6829 -- Direct controlled types do not inherit Finalize_Storage_Only flag
6831 if not Is_Controlled (Parent_Type) then
6832 Set_Finalize_Storage_Only
6833 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
6836 -- Construct the implicit full view by deriving from full view of the
6837 -- parent type. In order to get proper visibility, we install the
6838 -- parent scope and its declarations.
6840 -- ??? If the parent is untagged private and its completion is
6841 -- tagged, this mechanism will not work because we cannot derive from
6842 -- the tagged full view unless we have an extension.
6844 if Present (Full_View (Parent_Type))
6845 and then not Is_Tagged_Type (Full_View (Parent_Type))
6846 and then not Is_Completion
6849 Make_Defining_Identifier
6850 (Sloc (Derived_Type), Chars (Derived_Type));
6851 Set_Is_Itype (Full_Der);
6852 Set_Has_Private_Declaration (Full_Der);
6853 Set_Has_Private_Declaration (Derived_Type);
6854 Set_Associated_Node_For_Itype (Full_Der, N);
6855 Set_Parent (Full_Der, Parent (Derived_Type));
6856 Set_Full_View (Derived_Type, Full_Der);
6858 if not In_Open_Scopes (Par_Scope) then
6859 Install_Private_Declarations (Par_Scope);
6860 Install_Visible_Declarations (Par_Scope);
6862 Uninstall_Declarations (Par_Scope);
6864 -- If parent scope is open and in another unit, and parent has a
6865 -- completion, then the derivation is taking place in the visible
6866 -- part of a child unit. In that case retrieve the full view of
6867 -- the parent momentarily.
6869 elsif not In_Same_Source_Unit (N, Parent_Type) then
6870 Full_P := Full_View (Parent_Type);
6871 Exchange_Declarations (Parent_Type);
6873 Exchange_Declarations (Full_P);
6875 -- Otherwise it is a local derivation
6881 Set_Scope (Full_Der, Current_Scope);
6882 Set_Is_First_Subtype (Full_Der,
6883 Is_First_Subtype (Derived_Type));
6884 Set_Has_Size_Clause (Full_Der, False);
6885 Set_Has_Alignment_Clause (Full_Der, False);
6886 Set_Next_Entity (Full_Der, Empty);
6887 Set_Has_Delayed_Freeze (Full_Der);
6888 Set_Is_Frozen (Full_Der, False);
6889 Set_Freeze_Node (Full_Der, Empty);
6890 Set_Depends_On_Private (Full_Der,
6891 Has_Private_Component (Full_Der));
6892 Set_Public_Status (Full_Der);
6896 Set_Has_Unknown_Discriminants (Derived_Type,
6897 Has_Unknown_Discriminants (Parent_Type));
6899 if Is_Private_Type (Derived_Type) then
6900 Set_Private_Dependents (Derived_Type, New_Elmt_List);
6903 if Is_Private_Type (Parent_Type)
6904 and then Base_Type (Parent_Type) = Parent_Type
6905 and then In_Open_Scopes (Scope (Parent_Type))
6907 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
6909 -- Check for unusual case where a type completed by a private
6910 -- derivation occurs within a package nested in a child unit, and
6911 -- the parent is declared in an ancestor.
6913 if Is_Child_Unit (Scope (Current_Scope))
6914 and then Is_Completion
6915 and then In_Private_Part (Current_Scope)
6916 and then Scope (Parent_Type) /= Current_Scope
6918 -- Note that if the parent has a completion in the private part,
6919 -- (which is itself a derivation from some other private type)
6920 -- it is that completion that is visible, there is no full view
6921 -- available, and no special processing is needed.
6923 and then Present (Full_View (Parent_Type))
6925 -- In this case, the full view of the parent type will become
6926 -- visible in the body of the enclosing child, and only then will
6927 -- the current type be possibly non-private. We build an
6928 -- underlying full view that will be installed when the enclosing
6929 -- child body is compiled.
6932 Make_Defining_Identifier
6933 (Sloc (Derived_Type), Chars (Derived_Type));
6934 Set_Is_Itype (Full_Der);
6935 Build_Itype_Reference (Full_Der, N);
6937 -- The full view will be used to swap entities on entry/exit to
6938 -- the body, and must appear in the entity list for the package.
6940 Append_Entity (Full_Der, Scope (Derived_Type));
6941 Set_Has_Private_Declaration (Full_Der);
6942 Set_Has_Private_Declaration (Derived_Type);
6943 Set_Associated_Node_For_Itype (Full_Der, N);
6944 Set_Parent (Full_Der, Parent (Derived_Type));
6945 Full_P := Full_View (Parent_Type);
6946 Exchange_Declarations (Parent_Type);
6948 Exchange_Declarations (Full_P);
6949 Set_Underlying_Full_View (Derived_Type, Full_Der);
6952 end Build_Derived_Private_Type;
6954 -------------------------------
6955 -- Build_Derived_Record_Type --
6956 -------------------------------
6960 -- Ideally we would like to use the same model of type derivation for
6961 -- tagged and untagged record types. Unfortunately this is not quite
6962 -- possible because the semantics of representation clauses is different
6963 -- for tagged and untagged records under inheritance. Consider the
6966 -- type R (...) is [tagged] record ... end record;
6967 -- type T (...) is new R (...) [with ...];
6969 -- The representation clauses for T can specify a completely different
6970 -- record layout from R's. Hence the same component can be placed in two
6971 -- very different positions in objects of type T and R. If R and T are
6972 -- tagged types, representation clauses for T can only specify the layout
6973 -- of non inherited components, thus components that are common in R and T
6974 -- have the same position in objects of type R and T.
6976 -- This has two implications. The first is that the entire tree for R's
6977 -- declaration needs to be copied for T in the untagged case, so that T
6978 -- can be viewed as a record type of its own with its own representation
6979 -- clauses. The second implication is the way we handle discriminants.
6980 -- Specifically, in the untagged case we need a way to communicate to Gigi
6981 -- what are the real discriminants in the record, while for the semantics
6982 -- we need to consider those introduced by the user to rename the
6983 -- discriminants in the parent type. This is handled by introducing the
6984 -- notion of stored discriminants. See below for more.
6986 -- Fortunately the way regular components are inherited can be handled in
6987 -- the same way in tagged and untagged types.
6989 -- To complicate things a bit more the private view of a private extension
6990 -- cannot be handled in the same way as the full view (for one thing the
6991 -- semantic rules are somewhat different). We will explain what differs
6994 -- 2. DISCRIMINANTS UNDER INHERITANCE
6996 -- The semantic rules governing the discriminants of derived types are
6999 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
7000 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
7002 -- If parent type has discriminants, then the discriminants that are
7003 -- declared in the derived type are [3.4 (11)]:
7005 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
7008 -- o Otherwise, each discriminant of the parent type (implicitly declared
7009 -- in the same order with the same specifications). In this case, the
7010 -- discriminants are said to be "inherited", or if unknown in the parent
7011 -- are also unknown in the derived type.
7013 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
7015 -- o The parent subtype shall be constrained;
7017 -- o If the parent type is not a tagged type, then each discriminant of
7018 -- the derived type shall be used in the constraint defining a parent
7019 -- subtype. [Implementation note: This ensures that the new discriminant
7020 -- can share storage with an existing discriminant.]
7022 -- For the derived type each discriminant of the parent type is either
7023 -- inherited, constrained to equal some new discriminant of the derived
7024 -- type, or constrained to the value of an expression.
7026 -- When inherited or constrained to equal some new discriminant, the
7027 -- parent discriminant and the discriminant of the derived type are said
7030 -- If a discriminant of the parent type is constrained to a specific value
7031 -- in the derived type definition, then the discriminant is said to be
7032 -- "specified" by that derived type definition.
7034 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
7036 -- We have spoken about stored discriminants in point 1 (introduction)
7037 -- above. There are two sort of stored discriminants: implicit and
7038 -- explicit. As long as the derived type inherits the same discriminants as
7039 -- the root record type, stored discriminants are the same as regular
7040 -- discriminants, and are said to be implicit. However, if any discriminant
7041 -- in the root type was renamed in the derived type, then the derived
7042 -- type will contain explicit stored discriminants. Explicit stored
7043 -- discriminants are discriminants in addition to the semantically visible
7044 -- discriminants defined for the derived type. Stored discriminants are
7045 -- used by Gigi to figure out what are the physical discriminants in
7046 -- objects of the derived type (see precise definition in einfo.ads).
7047 -- As an example, consider the following:
7049 -- type R (D1, D2, D3 : Int) is record ... end record;
7050 -- type T1 is new R;
7051 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
7052 -- type T3 is new T2;
7053 -- type T4 (Y : Int) is new T3 (Y, 99);
7055 -- The following table summarizes the discriminants and stored
7056 -- discriminants in R and T1 through T4.
7058 -- Type Discrim Stored Discrim Comment
7059 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
7060 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
7061 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
7062 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
7063 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
7065 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
7066 -- find the corresponding discriminant in the parent type, while
7067 -- Original_Record_Component (abbreviated ORC below), the actual physical
7068 -- component that is renamed. Finally the field Is_Completely_Hidden
7069 -- (abbreviated ICH below) is set for all explicit stored discriminants
7070 -- (see einfo.ads for more info). For the above example this gives:
7072 -- Discrim CD ORC ICH
7073 -- ^^^^^^^ ^^ ^^^ ^^^
7074 -- D1 in R empty itself no
7075 -- D2 in R empty itself no
7076 -- D3 in R empty itself no
7078 -- D1 in T1 D1 in R itself no
7079 -- D2 in T1 D2 in R itself no
7080 -- D3 in T1 D3 in R itself no
7082 -- X1 in T2 D3 in T1 D3 in T2 no
7083 -- X2 in T2 D1 in T1 D1 in T2 no
7084 -- D1 in T2 empty itself yes
7085 -- D2 in T2 empty itself yes
7086 -- D3 in T2 empty itself yes
7088 -- X1 in T3 X1 in T2 D3 in T3 no
7089 -- X2 in T3 X2 in T2 D1 in T3 no
7090 -- D1 in T3 empty itself yes
7091 -- D2 in T3 empty itself yes
7092 -- D3 in T3 empty itself yes
7094 -- Y in T4 X1 in T3 D3 in T3 no
7095 -- D1 in T3 empty itself yes
7096 -- D2 in T3 empty itself yes
7097 -- D3 in T3 empty itself yes
7099 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
7101 -- Type derivation for tagged types is fairly straightforward. If no
7102 -- discriminants are specified by the derived type, these are inherited
7103 -- from the parent. No explicit stored discriminants are ever necessary.
7104 -- The only manipulation that is done to the tree is that of adding a
7105 -- _parent field with parent type and constrained to the same constraint
7106 -- specified for the parent in the derived type definition. For instance:
7108 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
7109 -- type T1 is new R with null record;
7110 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
7112 -- are changed into:
7114 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
7115 -- _parent : R (D1, D2, D3);
7118 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
7119 -- _parent : T1 (X2, 88, X1);
7122 -- The discriminants actually present in R, T1 and T2 as well as their CD,
7123 -- ORC and ICH fields are:
7125 -- Discrim CD ORC ICH
7126 -- ^^^^^^^ ^^ ^^^ ^^^
7127 -- D1 in R empty itself no
7128 -- D2 in R empty itself no
7129 -- D3 in R empty itself no
7131 -- D1 in T1 D1 in R D1 in R no
7132 -- D2 in T1 D2 in R D2 in R no
7133 -- D3 in T1 D3 in R D3 in R no
7135 -- X1 in T2 D3 in T1 D3 in R no
7136 -- X2 in T2 D1 in T1 D1 in R no
7138 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
7140 -- Regardless of whether we dealing with a tagged or untagged type
7141 -- we will transform all derived type declarations of the form
7143 -- type T is new R (...) [with ...];
7145 -- subtype S is R (...);
7146 -- type T is new S [with ...];
7148 -- type BT is new R [with ...];
7149 -- subtype T is BT (...);
7151 -- That is, the base derived type is constrained only if it has no
7152 -- discriminants. The reason for doing this is that GNAT's semantic model
7153 -- assumes that a base type with discriminants is unconstrained.
7155 -- Note that, strictly speaking, the above transformation is not always
7156 -- correct. Consider for instance the following excerpt from ACVC b34011a:
7158 -- procedure B34011A is
7159 -- type REC (D : integer := 0) is record
7164 -- type T6 is new Rec;
7165 -- function F return T6;
7170 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
7173 -- The definition of Q6.U is illegal. However transforming Q6.U into
7175 -- type BaseU is new T6;
7176 -- subtype U is BaseU (Q6.F.I)
7178 -- turns U into a legal subtype, which is incorrect. To avoid this problem
7179 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
7180 -- the transformation described above.
7182 -- There is another instance where the above transformation is incorrect.
7186 -- type Base (D : Integer) is tagged null record;
7187 -- procedure P (X : Base);
7189 -- type Der is new Base (2) with null record;
7190 -- procedure P (X : Der);
7193 -- Then the above transformation turns this into
7195 -- type Der_Base is new Base with null record;
7196 -- -- procedure P (X : Base) is implicitly inherited here
7197 -- -- as procedure P (X : Der_Base).
7199 -- subtype Der is Der_Base (2);
7200 -- procedure P (X : Der);
7201 -- -- The overriding of P (X : Der_Base) is illegal since we
7202 -- -- have a parameter conformance problem.
7204 -- To get around this problem, after having semantically processed Der_Base
7205 -- and the rewritten subtype declaration for Der, we copy Der_Base field
7206 -- Discriminant_Constraint from Der so that when parameter conformance is
7207 -- checked when P is overridden, no semantic errors are flagged.
7209 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
7211 -- Regardless of whether we are dealing with a tagged or untagged type
7212 -- we will transform all derived type declarations of the form
7214 -- type R (D1, .., Dn : ...) is [tagged] record ...;
7215 -- type T is new R [with ...];
7217 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
7219 -- The reason for such transformation is that it allows us to implement a
7220 -- very clean form of component inheritance as explained below.
7222 -- Note that this transformation is not achieved by direct tree rewriting
7223 -- and manipulation, but rather by redoing the semantic actions that the
7224 -- above transformation will entail. This is done directly in routine
7225 -- Inherit_Components.
7227 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
7229 -- In both tagged and untagged derived types, regular non discriminant
7230 -- components are inherited in the derived type from the parent type. In
7231 -- the absence of discriminants component, inheritance is straightforward
7232 -- as components can simply be copied from the parent.
7234 -- If the parent has discriminants, inheriting components constrained with
7235 -- these discriminants requires caution. Consider the following example:
7237 -- type R (D1, D2 : Positive) is [tagged] record
7238 -- S : String (D1 .. D2);
7241 -- type T1 is new R [with null record];
7242 -- type T2 (X : positive) is new R (1, X) [with null record];
7244 -- As explained in 6. above, T1 is rewritten as
7245 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
7246 -- which makes the treatment for T1 and T2 identical.
7248 -- What we want when inheriting S, is that references to D1 and D2 in R are
7249 -- replaced with references to their correct constraints, i.e. D1 and D2 in
7250 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
7251 -- with either discriminant references in the derived type or expressions.
7252 -- This replacement is achieved as follows: before inheriting R's
7253 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
7254 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
7255 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
7256 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
7257 -- by String (1 .. X).
7259 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
7261 -- We explain here the rules governing private type extensions relevant to
7262 -- type derivation. These rules are explained on the following example:
7264 -- type D [(...)] is new A [(...)] with private; <-- partial view
7265 -- type D [(...)] is new P [(...)] with null record; <-- full view
7267 -- Type A is called the ancestor subtype of the private extension.
7268 -- Type P is the parent type of the full view of the private extension. It
7269 -- must be A or a type derived from A.
7271 -- The rules concerning the discriminants of private type extensions are
7274 -- o If a private extension inherits known discriminants from the ancestor
7275 -- subtype, then the full view shall also inherit its discriminants from
7276 -- the ancestor subtype and the parent subtype of the full view shall be
7277 -- constrained if and only if the ancestor subtype is constrained.
7279 -- o If a partial view has unknown discriminants, then the full view may
7280 -- define a definite or an indefinite subtype, with or without
7283 -- o If a partial view has neither known nor unknown discriminants, then
7284 -- the full view shall define a definite subtype.
7286 -- o If the ancestor subtype of a private extension has constrained
7287 -- discriminants, then the parent subtype of the full view shall impose a
7288 -- statically matching constraint on those discriminants.
7290 -- This means that only the following forms of private extensions are
7293 -- type D is new A with private; <-- partial view
7294 -- type D is new P with null record; <-- full view
7296 -- If A has no discriminants than P has no discriminants, otherwise P must
7297 -- inherit A's discriminants.
7299 -- type D is new A (...) with private; <-- partial view
7300 -- type D is new P (:::) with null record; <-- full view
7302 -- P must inherit A's discriminants and (...) and (:::) must statically
7305 -- subtype A is R (...);
7306 -- type D is new A with private; <-- partial view
7307 -- type D is new P with null record; <-- full view
7309 -- P must have inherited R's discriminants and must be derived from A or
7310 -- any of its subtypes.
7312 -- type D (..) is new A with private; <-- partial view
7313 -- type D (..) is new P [(:::)] with null record; <-- full view
7315 -- No specific constraints on P's discriminants or constraint (:::).
7316 -- Note that A can be unconstrained, but the parent subtype P must either
7317 -- be constrained or (:::) must be present.
7319 -- type D (..) is new A [(...)] with private; <-- partial view
7320 -- type D (..) is new P [(:::)] with null record; <-- full view
7322 -- P's constraints on A's discriminants must statically match those
7323 -- imposed by (...).
7325 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
7327 -- The full view of a private extension is handled exactly as described
7328 -- above. The model chose for the private view of a private extension is
7329 -- the same for what concerns discriminants (i.e. they receive the same
7330 -- treatment as in the tagged case). However, the private view of the
7331 -- private extension always inherits the components of the parent base,
7332 -- without replacing any discriminant reference. Strictly speaking this is
7333 -- incorrect. However, Gigi never uses this view to generate code so this
7334 -- is a purely semantic issue. In theory, a set of transformations similar
7335 -- to those given in 5. and 6. above could be applied to private views of
7336 -- private extensions to have the same model of component inheritance as
7337 -- for non private extensions. However, this is not done because it would
7338 -- further complicate private type processing. Semantically speaking, this
7339 -- leaves us in an uncomfortable situation. As an example consider:
7342 -- type R (D : integer) is tagged record
7343 -- S : String (1 .. D);
7345 -- procedure P (X : R);
7346 -- type T is new R (1) with private;
7348 -- type T is new R (1) with null record;
7351 -- This is transformed into:
7354 -- type R (D : integer) is tagged record
7355 -- S : String (1 .. D);
7357 -- procedure P (X : R);
7358 -- type T is new R (1) with private;
7360 -- type BaseT is new R with null record;
7361 -- subtype T is BaseT (1);
7364 -- (strictly speaking the above is incorrect Ada)
7366 -- From the semantic standpoint the private view of private extension T
7367 -- should be flagged as constrained since one can clearly have
7371 -- in a unit withing Pack. However, when deriving subprograms for the
7372 -- private view of private extension T, T must be seen as unconstrained
7373 -- since T has discriminants (this is a constraint of the current
7374 -- subprogram derivation model). Thus, when processing the private view of
7375 -- a private extension such as T, we first mark T as unconstrained, we
7376 -- process it, we perform program derivation and just before returning from
7377 -- Build_Derived_Record_Type we mark T as constrained.
7379 -- ??? Are there are other uncomfortable cases that we will have to
7382 -- 10. RECORD_TYPE_WITH_PRIVATE complications
7384 -- Types that are derived from a visible record type and have a private
7385 -- extension present other peculiarities. They behave mostly like private
7386 -- types, but if they have primitive operations defined, these will not
7387 -- have the proper signatures for further inheritance, because other
7388 -- primitive operations will use the implicit base that we define for
7389 -- private derivations below. This affect subprogram inheritance (see
7390 -- Derive_Subprograms for details). We also derive the implicit base from
7391 -- the base type of the full view, so that the implicit base is a record
7392 -- type and not another private type, This avoids infinite loops.
7394 procedure Build_Derived_Record_Type
7396 Parent_Type : Entity_Id;
7397 Derived_Type : Entity_Id;
7398 Derive_Subps : Boolean := True)
7400 Discriminant_Specs : constant Boolean :=
7401 Present (Discriminant_Specifications (N));
7402 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
7403 Loc : constant Source_Ptr := Sloc (N);
7404 Private_Extension : constant Boolean :=
7405 Nkind (N) = N_Private_Extension_Declaration;
7406 Assoc_List : Elist_Id;
7407 Constraint_Present : Boolean;
7409 Discrim : Entity_Id;
7411 Inherit_Discrims : Boolean := False;
7412 Last_Discrim : Entity_Id;
7413 New_Base : Entity_Id;
7415 New_Discrs : Elist_Id;
7416 New_Indic : Node_Id;
7417 Parent_Base : Entity_Id;
7418 Save_Etype : Entity_Id;
7419 Save_Discr_Constr : Elist_Id;
7420 Save_Next_Entity : Entity_Id;
7423 Discs : Elist_Id := New_Elmt_List;
7424 -- An empty Discs list means that there were no constraints in the
7425 -- subtype indication or that there was an error processing it.
7428 if Ekind (Parent_Type) = E_Record_Type_With_Private
7429 and then Present (Full_View (Parent_Type))
7430 and then Has_Discriminants (Parent_Type)
7432 Parent_Base := Base_Type (Full_View (Parent_Type));
7434 Parent_Base := Base_Type (Parent_Type);
7437 -- AI05-0115 : if this is a derivation from a private type in some
7438 -- other scope that may lead to invisible components for the derived
7439 -- type, mark it accordingly.
7441 if Is_Private_Type (Parent_Type) then
7442 if Scope (Parent_Type) = Scope (Derived_Type) then
7445 elsif In_Open_Scopes (Scope (Parent_Type))
7446 and then In_Private_Part (Scope (Parent_Type))
7451 Set_Has_Private_Ancestor (Derived_Type);
7455 Set_Has_Private_Ancestor
7456 (Derived_Type, Has_Private_Ancestor (Parent_Type));
7459 -- Before we start the previously documented transformations, here is
7460 -- little fix for size and alignment of tagged types. Normally when we
7461 -- derive type D from type P, we copy the size and alignment of P as the
7462 -- default for D, and in the absence of explicit representation clauses
7463 -- for D, the size and alignment are indeed the same as the parent.
7465 -- But this is wrong for tagged types, since fields may be added, and
7466 -- the default size may need to be larger, and the default alignment may
7467 -- need to be larger.
7469 -- We therefore reset the size and alignment fields in the tagged case.
7470 -- Note that the size and alignment will in any case be at least as
7471 -- large as the parent type (since the derived type has a copy of the
7472 -- parent type in the _parent field)
7474 -- The type is also marked as being tagged here, which is needed when
7475 -- processing components with a self-referential anonymous access type
7476 -- in the call to Check_Anonymous_Access_Components below. Note that
7477 -- this flag is also set later on for completeness.
7480 Set_Is_Tagged_Type (Derived_Type);
7481 Init_Size_Align (Derived_Type);
7484 -- STEP 0a: figure out what kind of derived type declaration we have
7486 if Private_Extension then
7488 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
7491 Type_Def := Type_Definition (N);
7493 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7494 -- Parent_Base can be a private type or private extension. However,
7495 -- for tagged types with an extension the newly added fields are
7496 -- visible and hence the Derived_Type is always an E_Record_Type.
7497 -- (except that the parent may have its own private fields).
7498 -- For untagged types we preserve the Ekind of the Parent_Base.
7500 if Present (Record_Extension_Part (Type_Def)) then
7501 Set_Ekind (Derived_Type, E_Record_Type);
7503 -- Create internal access types for components with anonymous
7506 if Ada_Version >= Ada_2005 then
7507 Check_Anonymous_Access_Components
7508 (N, Derived_Type, Derived_Type,
7509 Component_List (Record_Extension_Part (Type_Def)));
7513 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7517 -- Indic can either be an N_Identifier if the subtype indication
7518 -- contains no constraint or an N_Subtype_Indication if the subtype
7519 -- indication has a constraint.
7521 Indic := Subtype_Indication (Type_Def);
7522 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
7524 -- Check that the type has visible discriminants. The type may be
7525 -- a private type with unknown discriminants whose full view has
7526 -- discriminants which are invisible.
7528 if Constraint_Present then
7529 if not Has_Discriminants (Parent_Base)
7531 (Has_Unknown_Discriminants (Parent_Base)
7532 and then Is_Private_Type (Parent_Base))
7535 ("invalid constraint: type has no discriminant",
7536 Constraint (Indic));
7538 Constraint_Present := False;
7539 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7541 elsif Is_Constrained (Parent_Type) then
7543 ("invalid constraint: parent type is already constrained",
7544 Constraint (Indic));
7546 Constraint_Present := False;
7547 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7551 -- STEP 0b: If needed, apply transformation given in point 5. above
7553 if not Private_Extension
7554 and then Has_Discriminants (Parent_Type)
7555 and then not Discriminant_Specs
7556 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
7558 -- First, we must analyze the constraint (see comment in point 5.)
7559 -- The constraint may come from the subtype indication of the full
7562 if Constraint_Present then
7563 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
7565 -- If there is no explicit constraint, there might be one that is
7566 -- inherited from a constrained parent type. In that case verify that
7567 -- it conforms to the constraint in the partial view. In perverse
7568 -- cases the parent subtypes of the partial and full view can have
7569 -- different constraints.
7571 elsif Present (Stored_Constraint (Parent_Type)) then
7572 New_Discrs := Stored_Constraint (Parent_Type);
7575 New_Discrs := No_Elist;
7578 if Has_Discriminants (Derived_Type)
7579 and then Has_Private_Declaration (Derived_Type)
7580 and then Present (Discriminant_Constraint (Derived_Type))
7581 and then Present (New_Discrs)
7583 -- Verify that constraints of the full view statically match
7584 -- those given in the partial view.
7590 C1 := First_Elmt (New_Discrs);
7591 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
7592 while Present (C1) and then Present (C2) loop
7593 if Fully_Conformant_Expressions (Node (C1), Node (C2))
7595 (Is_OK_Static_Expression (Node (C1))
7596 and then Is_OK_Static_Expression (Node (C2))
7598 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
7603 if Constraint_Present then
7605 ("constraint not conformant to previous declaration",
7609 ("constraint of full view is incompatible "
7610 & "with partial view", N);
7620 -- Insert and analyze the declaration for the unconstrained base type
7622 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
7625 Make_Full_Type_Declaration (Loc,
7626 Defining_Identifier => New_Base,
7628 Make_Derived_Type_Definition (Loc,
7629 Abstract_Present => Abstract_Present (Type_Def),
7630 Limited_Present => Limited_Present (Type_Def),
7631 Subtype_Indication =>
7632 New_Occurrence_Of (Parent_Base, Loc),
7633 Record_Extension_Part =>
7634 Relocate_Node (Record_Extension_Part (Type_Def)),
7635 Interface_List => Interface_List (Type_Def)));
7637 Set_Parent (New_Decl, Parent (N));
7638 Mark_Rewrite_Insertion (New_Decl);
7639 Insert_Before (N, New_Decl);
7641 -- In the extension case, make sure ancestor is frozen appropriately
7642 -- (see also non-discriminated case below).
7644 if Present (Record_Extension_Part (Type_Def))
7645 or else Is_Interface (Parent_Base)
7647 Freeze_Before (New_Decl, Parent_Type);
7650 -- Note that this call passes False for the Derive_Subps parameter
7651 -- because subprogram derivation is deferred until after creating
7652 -- the subtype (see below).
7655 (New_Decl, Parent_Base, New_Base,
7656 Is_Completion => True, Derive_Subps => False);
7658 -- ??? This needs re-examination to determine whether the
7659 -- above call can simply be replaced by a call to Analyze.
7661 Set_Analyzed (New_Decl);
7663 -- Insert and analyze the declaration for the constrained subtype
7665 if Constraint_Present then
7667 Make_Subtype_Indication (Loc,
7668 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
7669 Constraint => Relocate_Node (Constraint (Indic)));
7673 Constr_List : constant List_Id := New_List;
7678 C := First_Elmt (Discriminant_Constraint (Parent_Type));
7679 while Present (C) loop
7682 -- It is safe here to call New_Copy_Tree since
7683 -- Force_Evaluation was called on each constraint in
7684 -- Build_Discriminant_Constraints.
7686 Append (New_Copy_Tree (Expr), To => Constr_List);
7692 Make_Subtype_Indication (Loc,
7693 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
7695 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
7700 Make_Subtype_Declaration (Loc,
7701 Defining_Identifier => Derived_Type,
7702 Subtype_Indication => New_Indic));
7706 -- Derivation of subprograms must be delayed until the full subtype
7707 -- has been established, to ensure proper overriding of subprograms
7708 -- inherited by full types. If the derivations occurred as part of
7709 -- the call to Build_Derived_Type above, then the check for type
7710 -- conformance would fail because earlier primitive subprograms
7711 -- could still refer to the full type prior the change to the new
7712 -- subtype and hence would not match the new base type created here.
7713 -- Subprograms are not derived, however, when Derive_Subps is False
7714 -- (since otherwise there could be redundant derivations).
7716 if Derive_Subps then
7717 Derive_Subprograms (Parent_Type, Derived_Type);
7720 -- For tagged types the Discriminant_Constraint of the new base itype
7721 -- is inherited from the first subtype so that no subtype conformance
7722 -- problem arise when the first subtype overrides primitive
7723 -- operations inherited by the implicit base type.
7726 Set_Discriminant_Constraint
7727 (New_Base, Discriminant_Constraint (Derived_Type));
7733 -- If we get here Derived_Type will have no discriminants or it will be
7734 -- a discriminated unconstrained base type.
7736 -- STEP 1a: perform preliminary actions/checks for derived tagged types
7740 -- The parent type is frozen for non-private extensions (RM 13.14(7))
7741 -- The declaration of a specific descendant of an interface type
7742 -- freezes the interface type (RM 13.14).
7744 if not Private_Extension or else Is_Interface (Parent_Base) then
7745 Freeze_Before (N, Parent_Type);
7748 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
7749 -- cannot be declared at a deeper level than its parent type is
7750 -- removed. The check on derivation within a generic body is also
7751 -- relaxed, but there's a restriction that a derived tagged type
7752 -- cannot be declared in a generic body if it's derived directly
7753 -- or indirectly from a formal type of that generic.
7755 if Ada_Version >= Ada_2005 then
7756 if Present (Enclosing_Generic_Body (Derived_Type)) then
7758 Ancestor_Type : Entity_Id;
7761 -- Check to see if any ancestor of the derived type is a
7764 Ancestor_Type := Parent_Type;
7765 while not Is_Generic_Type (Ancestor_Type)
7766 and then Etype (Ancestor_Type) /= Ancestor_Type
7768 Ancestor_Type := Etype (Ancestor_Type);
7771 -- If the derived type does have a formal type as an
7772 -- ancestor, then it's an error if the derived type is
7773 -- declared within the body of the generic unit that
7774 -- declares the formal type in its generic formal part. It's
7775 -- sufficient to check whether the ancestor type is declared
7776 -- inside the same generic body as the derived type (such as
7777 -- within a nested generic spec), in which case the
7778 -- derivation is legal. If the formal type is declared
7779 -- outside of that generic body, then it's guaranteed that
7780 -- the derived type is declared within the generic body of
7781 -- the generic unit declaring the formal type.
7783 if Is_Generic_Type (Ancestor_Type)
7784 and then Enclosing_Generic_Body (Ancestor_Type) /=
7785 Enclosing_Generic_Body (Derived_Type)
7788 ("parent type of& must not be descendant of formal type"
7789 & " of an enclosing generic body",
7790 Indic, Derived_Type);
7795 elsif Type_Access_Level (Derived_Type) /=
7796 Type_Access_Level (Parent_Type)
7797 and then not Is_Generic_Type (Derived_Type)
7799 if Is_Controlled (Parent_Type) then
7801 ("controlled type must be declared at the library level",
7805 ("type extension at deeper accessibility level than parent",
7811 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
7815 and then GB /= Enclosing_Generic_Body (Parent_Base)
7818 ("parent type of& must not be outside generic body"
7820 Indic, Derived_Type);
7826 -- Ada 2005 (AI-251)
7828 if Ada_Version >= Ada_2005 and then Is_Tagged then
7830 -- "The declaration of a specific descendant of an interface type
7831 -- freezes the interface type" (RM 13.14).
7836 if Is_Non_Empty_List (Interface_List (Type_Def)) then
7837 Iface := First (Interface_List (Type_Def));
7838 while Present (Iface) loop
7839 Freeze_Before (N, Etype (Iface));
7846 -- STEP 1b : preliminary cleanup of the full view of private types
7848 -- If the type is already marked as having discriminants, then it's the
7849 -- completion of a private type or private extension and we need to
7850 -- retain the discriminants from the partial view if the current
7851 -- declaration has Discriminant_Specifications so that we can verify
7852 -- conformance. However, we must remove any existing components that
7853 -- were inherited from the parent (and attached in Copy_And_Swap)
7854 -- because the full type inherits all appropriate components anyway, and
7855 -- we do not want the partial view's components interfering.
7857 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
7858 Discrim := First_Discriminant (Derived_Type);
7860 Last_Discrim := Discrim;
7861 Next_Discriminant (Discrim);
7862 exit when No (Discrim);
7865 Set_Last_Entity (Derived_Type, Last_Discrim);
7867 -- In all other cases wipe out the list of inherited components (even
7868 -- inherited discriminants), it will be properly rebuilt here.
7871 Set_First_Entity (Derived_Type, Empty);
7872 Set_Last_Entity (Derived_Type, Empty);
7875 -- STEP 1c: Initialize some flags for the Derived_Type
7877 -- The following flags must be initialized here so that
7878 -- Process_Discriminants can check that discriminants of tagged types do
7879 -- not have a default initial value and that access discriminants are
7880 -- only specified for limited records. For completeness, these flags are
7881 -- also initialized along with all the other flags below.
7883 -- AI-419: Limitedness is not inherited from an interface parent, so to
7884 -- be limited in that case the type must be explicitly declared as
7885 -- limited. However, task and protected interfaces are always limited.
7887 if Limited_Present (Type_Def) then
7888 Set_Is_Limited_Record (Derived_Type);
7890 elsif Is_Limited_Record (Parent_Type)
7891 or else (Present (Full_View (Parent_Type))
7892 and then Is_Limited_Record (Full_View (Parent_Type)))
7894 if not Is_Interface (Parent_Type)
7895 or else Is_Synchronized_Interface (Parent_Type)
7896 or else Is_Protected_Interface (Parent_Type)
7897 or else Is_Task_Interface (Parent_Type)
7899 Set_Is_Limited_Record (Derived_Type);
7903 -- STEP 2a: process discriminants of derived type if any
7905 Push_Scope (Derived_Type);
7907 if Discriminant_Specs then
7908 Set_Has_Unknown_Discriminants (Derived_Type, False);
7910 -- The following call initializes fields Has_Discriminants and
7911 -- Discriminant_Constraint, unless we are processing the completion
7912 -- of a private type declaration.
7914 Check_Or_Process_Discriminants (N, Derived_Type);
7916 -- For untagged types, the constraint on the Parent_Type must be
7917 -- present and is used to rename the discriminants.
7919 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
7920 Error_Msg_N ("untagged parent must have discriminants", Indic);
7922 elsif not Is_Tagged and then not Constraint_Present then
7924 ("discriminant constraint needed for derived untagged records",
7927 -- Otherwise the parent subtype must be constrained unless we have a
7928 -- private extension.
7930 elsif not Constraint_Present
7931 and then not Private_Extension
7932 and then not Is_Constrained (Parent_Type)
7935 ("unconstrained type not allowed in this context", Indic);
7937 elsif Constraint_Present then
7938 -- The following call sets the field Corresponding_Discriminant
7939 -- for the discriminants in the Derived_Type.
7941 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
7943 -- For untagged types all new discriminants must rename
7944 -- discriminants in the parent. For private extensions new
7945 -- discriminants cannot rename old ones (implied by [7.3(13)]).
7947 Discrim := First_Discriminant (Derived_Type);
7948 while Present (Discrim) loop
7950 and then No (Corresponding_Discriminant (Discrim))
7953 ("new discriminants must constrain old ones", Discrim);
7955 elsif Private_Extension
7956 and then Present (Corresponding_Discriminant (Discrim))
7959 ("only static constraints allowed for parent"
7960 & " discriminants in the partial view", Indic);
7964 -- If a new discriminant is used in the constraint, then its
7965 -- subtype must be statically compatible with the parent
7966 -- discriminant's subtype (3.7(15)).
7968 -- However, if the record contains an array constrained by
7969 -- the discriminant but with some different bound, the compiler
7970 -- attemps to create a smaller range for the discriminant type.
7971 -- (See exp_ch3.Adjust_Discriminants). In this case, where
7972 -- the discriminant type is a scalar type, the check must use
7973 -- the original discriminant type in the parent declaration.
7976 Corr_Disc : constant Entity_Id :=
7977 Corresponding_Discriminant (Discrim);
7978 Disc_Type : constant Entity_Id := Etype (Discrim);
7979 Corr_Type : Entity_Id;
7982 if Present (Corr_Disc) then
7983 if Is_Scalar_Type (Disc_Type) then
7985 Entity (Discriminant_Type (Parent (Corr_Disc)));
7987 Corr_Type := Etype (Corr_Disc);
7991 Subtypes_Statically_Compatible (Disc_Type, Corr_Type)
7994 ("subtype must be compatible "
7995 & "with parent discriminant",
8001 Next_Discriminant (Discrim);
8004 -- Check whether the constraints of the full view statically
8005 -- match those imposed by the parent subtype [7.3(13)].
8007 if Present (Stored_Constraint (Derived_Type)) then
8012 C1 := First_Elmt (Discs);
8013 C2 := First_Elmt (Stored_Constraint (Derived_Type));
8014 while Present (C1) and then Present (C2) loop
8016 Fully_Conformant_Expressions (Node (C1), Node (C2))
8019 ("not conformant with previous declaration",
8030 -- STEP 2b: No new discriminants, inherit discriminants if any
8033 if Private_Extension then
8034 Set_Has_Unknown_Discriminants
8036 Has_Unknown_Discriminants (Parent_Type)
8037 or else Unknown_Discriminants_Present (N));
8039 -- The partial view of the parent may have unknown discriminants,
8040 -- but if the full view has discriminants and the parent type is
8041 -- in scope they must be inherited.
8043 elsif Has_Unknown_Discriminants (Parent_Type)
8045 (not Has_Discriminants (Parent_Type)
8046 or else not In_Open_Scopes (Scope (Parent_Type)))
8048 Set_Has_Unknown_Discriminants (Derived_Type);
8051 if not Has_Unknown_Discriminants (Derived_Type)
8052 and then not Has_Unknown_Discriminants (Parent_Base)
8053 and then Has_Discriminants (Parent_Type)
8055 Inherit_Discrims := True;
8056 Set_Has_Discriminants
8057 (Derived_Type, True);
8058 Set_Discriminant_Constraint
8059 (Derived_Type, Discriminant_Constraint (Parent_Base));
8062 -- The following test is true for private types (remember
8063 -- transformation 5. is not applied to those) and in an error
8066 if Constraint_Present then
8067 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
8070 -- For now mark a new derived type as constrained only if it has no
8071 -- discriminants. At the end of Build_Derived_Record_Type we properly
8072 -- set this flag in the case of private extensions. See comments in
8073 -- point 9. just before body of Build_Derived_Record_Type.
8077 not (Inherit_Discrims
8078 or else Has_Unknown_Discriminants (Derived_Type)));
8081 -- STEP 3: initialize fields of derived type
8083 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
8084 Set_Stored_Constraint (Derived_Type, No_Elist);
8086 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
8087 -- but cannot be interfaces
8089 if not Private_Extension
8090 and then Ekind (Derived_Type) /= E_Private_Type
8091 and then Ekind (Derived_Type) /= E_Limited_Private_Type
8093 if Interface_Present (Type_Def) then
8094 Analyze_Interface_Declaration (Derived_Type, Type_Def);
8097 Set_Interfaces (Derived_Type, No_Elist);
8100 -- Fields inherited from the Parent_Type
8102 Set_Has_Specified_Layout
8103 (Derived_Type, Has_Specified_Layout (Parent_Type));
8104 Set_Is_Limited_Composite
8105 (Derived_Type, Is_Limited_Composite (Parent_Type));
8106 Set_Is_Private_Composite
8107 (Derived_Type, Is_Private_Composite (Parent_Type));
8109 -- Fields inherited from the Parent_Base
8111 Set_Has_Controlled_Component
8112 (Derived_Type, Has_Controlled_Component (Parent_Base));
8113 Set_Has_Non_Standard_Rep
8114 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8115 Set_Has_Primitive_Operations
8116 (Derived_Type, Has_Primitive_Operations (Parent_Base));
8118 -- Fields inherited from the Parent_Base in the non-private case
8120 if Ekind (Derived_Type) = E_Record_Type then
8121 Set_Has_Complex_Representation
8122 (Derived_Type, Has_Complex_Representation (Parent_Base));
8125 -- Fields inherited from the Parent_Base for record types
8127 if Is_Record_Type (Derived_Type) then
8130 Parent_Full : Entity_Id;
8133 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8134 -- Parent_Base can be a private type or private extension. Go
8135 -- to the full view here to get the E_Record_Type specific flags.
8137 if Present (Full_View (Parent_Base)) then
8138 Parent_Full := Full_View (Parent_Base);
8140 Parent_Full := Parent_Base;
8143 Set_OK_To_Reorder_Components
8144 (Derived_Type, OK_To_Reorder_Components (Parent_Full));
8148 -- Set fields for private derived types
8150 if Is_Private_Type (Derived_Type) then
8151 Set_Depends_On_Private (Derived_Type, True);
8152 Set_Private_Dependents (Derived_Type, New_Elmt_List);
8154 -- Inherit fields from non private record types. If this is the
8155 -- completion of a derivation from a private type, the parent itself
8156 -- is private, and the attributes come from its full view, which must
8160 if Is_Private_Type (Parent_Base)
8161 and then not Is_Record_Type (Parent_Base)
8163 Set_Component_Alignment
8164 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
8166 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
8168 Set_Component_Alignment
8169 (Derived_Type, Component_Alignment (Parent_Base));
8171 (Derived_Type, C_Pass_By_Copy (Parent_Base));
8175 -- Set fields for tagged types
8178 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
8180 -- All tagged types defined in Ada.Finalization are controlled
8182 if Chars (Scope (Derived_Type)) = Name_Finalization
8183 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
8184 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
8186 Set_Is_Controlled (Derived_Type);
8188 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
8191 -- Minor optimization: there is no need to generate the class-wide
8192 -- entity associated with an underlying record view.
8194 if not Is_Underlying_Record_View (Derived_Type) then
8195 Make_Class_Wide_Type (Derived_Type);
8198 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
8200 if Has_Discriminants (Derived_Type)
8201 and then Constraint_Present
8203 Set_Stored_Constraint
8204 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
8207 if Ada_Version >= Ada_2005 then
8209 Ifaces_List : Elist_Id;
8212 -- Checks rules 3.9.4 (13/2 and 14/2)
8214 if Comes_From_Source (Derived_Type)
8215 and then not Is_Private_Type (Derived_Type)
8216 and then Is_Interface (Parent_Type)
8217 and then not Is_Interface (Derived_Type)
8219 if Is_Task_Interface (Parent_Type) then
8221 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
8224 elsif Is_Protected_Interface (Parent_Type) then
8226 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
8231 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
8233 Check_Interfaces (N, Type_Def);
8235 -- Ada 2005 (AI-251): Collect the list of progenitors that are
8236 -- not already in the parents.
8240 Ifaces_List => Ifaces_List,
8241 Exclude_Parents => True);
8243 Set_Interfaces (Derived_Type, Ifaces_List);
8245 -- If the derived type is the anonymous type created for
8246 -- a declaration whose parent has a constraint, propagate
8247 -- the interface list to the source type. This must be done
8248 -- prior to the completion of the analysis of the source type
8249 -- because the components in the extension may contain current
8250 -- instances whose legality depends on some ancestor.
8252 if Is_Itype (Derived_Type) then
8254 Def : constant Node_Id :=
8255 Associated_Node_For_Itype (Derived_Type);
8258 and then Nkind (Def) = N_Full_Type_Declaration
8261 (Defining_Identifier (Def), Ifaces_List);
8269 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
8270 Set_Has_Non_Standard_Rep
8271 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8274 -- STEP 4: Inherit components from the parent base and constrain them.
8275 -- Apply the second transformation described in point 6. above.
8277 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
8278 or else not Has_Discriminants (Parent_Type)
8279 or else not Is_Constrained (Parent_Type)
8283 Constrs := Discriminant_Constraint (Parent_Type);
8288 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
8290 -- STEP 5a: Copy the parent record declaration for untagged types
8292 if not Is_Tagged then
8294 -- Discriminant_Constraint (Derived_Type) has been properly
8295 -- constructed. Save it and temporarily set it to Empty because we
8296 -- do not want the call to New_Copy_Tree below to mess this list.
8298 if Has_Discriminants (Derived_Type) then
8299 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
8300 Set_Discriminant_Constraint (Derived_Type, No_Elist);
8302 Save_Discr_Constr := No_Elist;
8305 -- Save the Etype field of Derived_Type. It is correctly set now,
8306 -- but the call to New_Copy tree may remap it to point to itself,
8307 -- which is not what we want. Ditto for the Next_Entity field.
8309 Save_Etype := Etype (Derived_Type);
8310 Save_Next_Entity := Next_Entity (Derived_Type);
8312 -- Assoc_List maps all stored discriminants in the Parent_Base to
8313 -- stored discriminants in the Derived_Type. It is fundamental that
8314 -- no types or itypes with discriminants other than the stored
8315 -- discriminants appear in the entities declared inside
8316 -- Derived_Type, since the back end cannot deal with it.
8320 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
8322 -- Restore the fields saved prior to the New_Copy_Tree call
8323 -- and compute the stored constraint.
8325 Set_Etype (Derived_Type, Save_Etype);
8326 Set_Next_Entity (Derived_Type, Save_Next_Entity);
8328 if Has_Discriminants (Derived_Type) then
8329 Set_Discriminant_Constraint
8330 (Derived_Type, Save_Discr_Constr);
8331 Set_Stored_Constraint
8332 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
8333 Replace_Components (Derived_Type, New_Decl);
8334 Set_Has_Implicit_Dereference
8335 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
8338 -- Insert the new derived type declaration
8340 Rewrite (N, New_Decl);
8342 -- STEP 5b: Complete the processing for record extensions in generics
8344 -- There is no completion for record extensions declared in the
8345 -- parameter part of a generic, so we need to complete processing for
8346 -- these generic record extensions here. The Record_Type_Definition call
8347 -- will change the Ekind of the components from E_Void to E_Component.
8349 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
8350 Record_Type_Definition (Empty, Derived_Type);
8352 -- STEP 5c: Process the record extension for non private tagged types
8354 elsif not Private_Extension then
8356 -- Add the _parent field in the derived type
8358 Expand_Record_Extension (Derived_Type, Type_Def);
8360 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
8361 -- implemented interfaces if we are in expansion mode
8364 and then Has_Interfaces (Derived_Type)
8366 Add_Interface_Tag_Components (N, Derived_Type);
8369 -- Analyze the record extension
8371 Record_Type_Definition
8372 (Record_Extension_Part (Type_Def), Derived_Type);
8377 -- Nothing else to do if there is an error in the derivation.
8378 -- An unusual case: the full view may be derived from a type in an
8379 -- instance, when the partial view was used illegally as an actual
8380 -- in that instance, leading to a circular definition.
8382 if Etype (Derived_Type) = Any_Type
8383 or else Etype (Parent_Type) = Derived_Type
8388 -- Set delayed freeze and then derive subprograms, we need to do
8389 -- this in this order so that derived subprograms inherit the
8390 -- derived freeze if necessary.
8392 Set_Has_Delayed_Freeze (Derived_Type);
8394 if Derive_Subps then
8395 Derive_Subprograms (Parent_Type, Derived_Type);
8398 -- If we have a private extension which defines a constrained derived
8399 -- type mark as constrained here after we have derived subprograms. See
8400 -- comment on point 9. just above the body of Build_Derived_Record_Type.
8402 if Private_Extension and then Inherit_Discrims then
8403 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
8404 Set_Is_Constrained (Derived_Type, True);
8405 Set_Discriminant_Constraint (Derived_Type, Discs);
8407 elsif Is_Constrained (Parent_Type) then
8409 (Derived_Type, True);
8410 Set_Discriminant_Constraint
8411 (Derived_Type, Discriminant_Constraint (Parent_Type));
8415 -- Update the class-wide type, which shares the now-completed entity
8416 -- list with its specific type. In case of underlying record views,
8417 -- we do not generate the corresponding class wide entity.
8420 and then not Is_Underlying_Record_View (Derived_Type)
8423 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
8425 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
8428 Check_Function_Writable_Actuals (N);
8429 end Build_Derived_Record_Type;
8431 ------------------------
8432 -- Build_Derived_Type --
8433 ------------------------
8435 procedure Build_Derived_Type
8437 Parent_Type : Entity_Id;
8438 Derived_Type : Entity_Id;
8439 Is_Completion : Boolean;
8440 Derive_Subps : Boolean := True)
8442 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
8445 -- Set common attributes
8447 Set_Scope (Derived_Type, Current_Scope);
8449 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8450 Set_Etype (Derived_Type, Parent_Base);
8451 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
8453 Set_Size_Info (Derived_Type, Parent_Type);
8454 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
8455 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
8456 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
8458 -- If the parent type is a private subtype, the convention on the base
8459 -- type may be set in the private part, and not propagated to the
8460 -- subtype until later, so we obtain the convention from the base type.
8462 Set_Convention (Derived_Type, Convention (Parent_Base));
8464 -- Propagate invariant information. The new type has invariants if
8465 -- they are inherited from the parent type, and these invariants can
8466 -- be further inherited, so both flags are set.
8468 -- We similarly inherit predicates
8470 if Has_Predicates (Parent_Type) then
8471 Set_Has_Predicates (Derived_Type);
8474 -- The derived type inherits the representation clauses of the parent.
8475 -- However, for a private type that is completed by a derivation, there
8476 -- may be operation attributes that have been specified already (stream
8477 -- attributes and External_Tag) and those must be provided. Finally,
8478 -- if the partial view is a private extension, the representation items
8479 -- of the parent have been inherited already, and should not be chained
8480 -- twice to the derived type.
8482 if Is_Tagged_Type (Parent_Type)
8483 and then Present (First_Rep_Item (Derived_Type))
8485 -- The existing items are either operational items or items inherited
8486 -- from a private extension declaration.
8490 -- Used to iterate over representation items of the derived type
8493 -- Last representation item of the (non-empty) representation
8494 -- item list of the derived type.
8496 Found : Boolean := False;
8499 Rep := First_Rep_Item (Derived_Type);
8501 while Present (Rep) loop
8502 if Rep = First_Rep_Item (Parent_Type) then
8507 Rep := Next_Rep_Item (Rep);
8509 if Present (Rep) then
8515 -- Here if we either encountered the parent type's first rep
8516 -- item on the derived type's rep item list (in which case
8517 -- Found is True, and we have nothing else to do), or if we
8518 -- reached the last rep item of the derived type, which is
8519 -- Last_Rep, in which case we further chain the parent type's
8520 -- rep items to those of the derived type.
8523 Set_Next_Rep_Item (Last_Rep, First_Rep_Item (Parent_Type));
8528 Set_First_Rep_Item (Derived_Type, First_Rep_Item (Parent_Type));
8531 -- If the parent type has delayed rep aspects, then mark the derived
8532 -- type as possibly inheriting a delayed rep aspect.
8534 if Has_Delayed_Rep_Aspects (Parent_Type) then
8535 Set_May_Inherit_Delayed_Rep_Aspects (Derived_Type);
8538 -- Type dependent processing
8540 case Ekind (Parent_Type) is
8541 when Numeric_Kind =>
8542 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
8545 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
8549 | Class_Wide_Kind =>
8550 Build_Derived_Record_Type
8551 (N, Parent_Type, Derived_Type, Derive_Subps);
8554 when Enumeration_Kind =>
8555 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
8558 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
8560 when Incomplete_Or_Private_Kind =>
8561 Build_Derived_Private_Type
8562 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
8564 -- For discriminated types, the derivation includes deriving
8565 -- primitive operations. For others it is done below.
8567 if Is_Tagged_Type (Parent_Type)
8568 or else Has_Discriminants (Parent_Type)
8569 or else (Present (Full_View (Parent_Type))
8570 and then Has_Discriminants (Full_View (Parent_Type)))
8575 when Concurrent_Kind =>
8576 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
8579 raise Program_Error;
8582 -- Nothing more to do if some error occurred
8584 if Etype (Derived_Type) = Any_Type then
8588 -- Set delayed freeze and then derive subprograms, we need to do this
8589 -- in this order so that derived subprograms inherit the derived freeze
8592 Set_Has_Delayed_Freeze (Derived_Type);
8594 if Derive_Subps then
8595 Derive_Subprograms (Parent_Type, Derived_Type);
8598 Set_Has_Primitive_Operations
8599 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
8600 end Build_Derived_Type;
8602 -----------------------
8603 -- Build_Discriminal --
8604 -----------------------
8606 procedure Build_Discriminal (Discrim : Entity_Id) is
8607 D_Minal : Entity_Id;
8608 CR_Disc : Entity_Id;
8611 -- A discriminal has the same name as the discriminant
8613 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8615 Set_Ekind (D_Minal, E_In_Parameter);
8616 Set_Mechanism (D_Minal, Default_Mechanism);
8617 Set_Etype (D_Minal, Etype (Discrim));
8618 Set_Scope (D_Minal, Current_Scope);
8620 Set_Discriminal (Discrim, D_Minal);
8621 Set_Discriminal_Link (D_Minal, Discrim);
8623 -- For task types, build at once the discriminants of the corresponding
8624 -- record, which are needed if discriminants are used in entry defaults
8625 -- and in family bounds.
8627 if Is_Concurrent_Type (Current_Scope)
8628 or else Is_Limited_Type (Current_Scope)
8630 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8632 Set_Ekind (CR_Disc, E_In_Parameter);
8633 Set_Mechanism (CR_Disc, Default_Mechanism);
8634 Set_Etype (CR_Disc, Etype (Discrim));
8635 Set_Scope (CR_Disc, Current_Scope);
8636 Set_Discriminal_Link (CR_Disc, Discrim);
8637 Set_CR_Discriminant (Discrim, CR_Disc);
8639 end Build_Discriminal;
8641 ------------------------------------
8642 -- Build_Discriminant_Constraints --
8643 ------------------------------------
8645 function Build_Discriminant_Constraints
8648 Derived_Def : Boolean := False) return Elist_Id
8650 C : constant Node_Id := Constraint (Def);
8651 Nb_Discr : constant Nat := Number_Discriminants (T);
8653 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
8654 -- Saves the expression corresponding to a given discriminant in T
8656 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
8657 -- Return the Position number within array Discr_Expr of a discriminant
8658 -- D within the discriminant list of the discriminated type T.
8660 procedure Process_Discriminant_Expression
8663 -- If this is a discriminant constraint on a partial view, do not
8664 -- generate an overflow check on the discriminant expression. The check
8665 -- will be generated when constraining the full view. Otherwise the
8666 -- backend creates duplicate symbols for the temporaries corresponding
8667 -- to the expressions to be checked, causing spurious assembler errors.
8673 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
8677 Disc := First_Discriminant (T);
8678 for J in Discr_Expr'Range loop
8683 Next_Discriminant (Disc);
8686 -- Note: Since this function is called on discriminants that are
8687 -- known to belong to the discriminated type, falling through the
8688 -- loop with no match signals an internal compiler error.
8690 raise Program_Error;
8693 -------------------------------------
8694 -- Process_Discriminant_Expression --
8695 -------------------------------------
8697 procedure Process_Discriminant_Expression
8701 BDT : constant Entity_Id := Base_Type (Etype (D));
8704 -- If this is a discriminant constraint on a partial view, do
8705 -- not generate an overflow on the discriminant expression. The
8706 -- check will be generated when constraining the full view.
8708 if Is_Private_Type (T)
8709 and then Present (Full_View (T))
8711 Analyze_And_Resolve (Expr, BDT, Suppress => Overflow_Check);
8713 Analyze_And_Resolve (Expr, BDT);
8715 end Process_Discriminant_Expression;
8717 -- Declarations local to Build_Discriminant_Constraints
8721 Elist : constant Elist_Id := New_Elmt_List;
8729 Discrim_Present : Boolean := False;
8731 -- Start of processing for Build_Discriminant_Constraints
8734 -- The following loop will process positional associations only.
8735 -- For a positional association, the (single) discriminant is
8736 -- implicitly specified by position, in textual order (RM 3.7.2).
8738 Discr := First_Discriminant (T);
8739 Constr := First (Constraints (C));
8740 for D in Discr_Expr'Range loop
8741 exit when Nkind (Constr) = N_Discriminant_Association;
8744 Error_Msg_N ("too few discriminants given in constraint", C);
8745 return New_Elmt_List;
8747 elsif Nkind (Constr) = N_Range
8748 or else (Nkind (Constr) = N_Attribute_Reference
8750 Attribute_Name (Constr) = Name_Range)
8753 ("a range is not a valid discriminant constraint", Constr);
8754 Discr_Expr (D) := Error;
8757 Process_Discriminant_Expression (Constr, Discr);
8758 Discr_Expr (D) := Constr;
8761 Next_Discriminant (Discr);
8765 if No (Discr) and then Present (Constr) then
8766 Error_Msg_N ("too many discriminants given in constraint", Constr);
8767 return New_Elmt_List;
8770 -- Named associations can be given in any order, but if both positional
8771 -- and named associations are used in the same discriminant constraint,
8772 -- then positional associations must occur first, at their normal
8773 -- position. Hence once a named association is used, the rest of the
8774 -- discriminant constraint must use only named associations.
8776 while Present (Constr) loop
8778 -- Positional association forbidden after a named association
8780 if Nkind (Constr) /= N_Discriminant_Association then
8781 Error_Msg_N ("positional association follows named one", Constr);
8782 return New_Elmt_List;
8784 -- Otherwise it is a named association
8787 -- E records the type of the discriminants in the named
8788 -- association. All the discriminants specified in the same name
8789 -- association must have the same type.
8793 -- Search the list of discriminants in T to see if the simple name
8794 -- given in the constraint matches any of them.
8796 Id := First (Selector_Names (Constr));
8797 while Present (Id) loop
8800 -- If Original_Discriminant is present, we are processing a
8801 -- generic instantiation and this is an instance node. We need
8802 -- to find the name of the corresponding discriminant in the
8803 -- actual record type T and not the name of the discriminant in
8804 -- the generic formal. Example:
8807 -- type G (D : int) is private;
8809 -- subtype W is G (D => 1);
8811 -- type Rec (X : int) is record ... end record;
8812 -- package Q is new P (G => Rec);
8814 -- At the point of the instantiation, formal type G is Rec
8815 -- and therefore when reanalyzing "subtype W is G (D => 1);"
8816 -- which really looks like "subtype W is Rec (D => 1);" at
8817 -- the point of instantiation, we want to find the discriminant
8818 -- that corresponds to D in Rec, i.e. X.
8820 if Present (Original_Discriminant (Id))
8821 and then In_Instance
8823 Discr := Find_Corresponding_Discriminant (Id, T);
8827 Discr := First_Discriminant (T);
8828 while Present (Discr) loop
8829 if Chars (Discr) = Chars (Id) then
8834 Next_Discriminant (Discr);
8838 Error_Msg_N ("& does not match any discriminant", Id);
8839 return New_Elmt_List;
8841 -- If the parent type is a generic formal, preserve the
8842 -- name of the discriminant for subsequent instances.
8843 -- see comment at the beginning of this if statement.
8845 elsif Is_Generic_Type (Root_Type (T)) then
8846 Set_Original_Discriminant (Id, Discr);
8850 Position := Pos_Of_Discr (T, Discr);
8852 if Present (Discr_Expr (Position)) then
8853 Error_Msg_N ("duplicate constraint for discriminant&", Id);
8856 -- Each discriminant specified in the same named association
8857 -- must be associated with a separate copy of the
8858 -- corresponding expression.
8860 if Present (Next (Id)) then
8861 Expr := New_Copy_Tree (Expression (Constr));
8862 Set_Parent (Expr, Parent (Expression (Constr)));
8864 Expr := Expression (Constr);
8867 Discr_Expr (Position) := Expr;
8868 Process_Discriminant_Expression (Expr, Discr);
8871 -- A discriminant association with more than one discriminant
8872 -- name is only allowed if the named discriminants are all of
8873 -- the same type (RM 3.7.1(8)).
8876 E := Base_Type (Etype (Discr));
8878 elsif Base_Type (Etype (Discr)) /= E then
8880 ("all discriminants in an association " &
8881 "must have the same type", Id);
8891 -- A discriminant constraint must provide exactly one value for each
8892 -- discriminant of the type (RM 3.7.1(8)).
8894 for J in Discr_Expr'Range loop
8895 if No (Discr_Expr (J)) then
8896 Error_Msg_N ("too few discriminants given in constraint", C);
8897 return New_Elmt_List;
8901 -- Determine if there are discriminant expressions in the constraint
8903 for J in Discr_Expr'Range loop
8904 if Denotes_Discriminant
8905 (Discr_Expr (J), Check_Concurrent => True)
8907 Discrim_Present := True;
8911 -- Build an element list consisting of the expressions given in the
8912 -- discriminant constraint and apply the appropriate checks. The list
8913 -- is constructed after resolving any named discriminant associations
8914 -- and therefore the expressions appear in the textual order of the
8917 Discr := First_Discriminant (T);
8918 for J in Discr_Expr'Range loop
8919 if Discr_Expr (J) /= Error then
8920 Append_Elmt (Discr_Expr (J), Elist);
8922 -- If any of the discriminant constraints is given by a
8923 -- discriminant and we are in a derived type declaration we
8924 -- have a discriminant renaming. Establish link between new
8925 -- and old discriminant.
8927 if Denotes_Discriminant (Discr_Expr (J)) then
8929 Set_Corresponding_Discriminant
8930 (Entity (Discr_Expr (J)), Discr);
8933 -- Force the evaluation of non-discriminant expressions.
8934 -- If we have found a discriminant in the constraint 3.4(26)
8935 -- and 3.8(18) demand that no range checks are performed are
8936 -- after evaluation. If the constraint is for a component
8937 -- definition that has a per-object constraint, expressions are
8938 -- evaluated but not checked either. In all other cases perform
8942 if Discrim_Present then
8945 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
8947 Has_Per_Object_Constraint
8948 (Defining_Identifier (Parent (Parent (Def))))
8952 elsif Is_Access_Type (Etype (Discr)) then
8953 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
8956 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
8959 Force_Evaluation (Discr_Expr (J));
8962 -- Check that the designated type of an access discriminant's
8963 -- expression is not a class-wide type unless the discriminant's
8964 -- designated type is also class-wide.
8966 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
8967 and then not Is_Class_Wide_Type
8968 (Designated_Type (Etype (Discr)))
8969 and then Etype (Discr_Expr (J)) /= Any_Type
8970 and then Is_Class_Wide_Type
8971 (Designated_Type (Etype (Discr_Expr (J))))
8973 Wrong_Type (Discr_Expr (J), Etype (Discr));
8975 elsif Is_Access_Type (Etype (Discr))
8976 and then not Is_Access_Constant (Etype (Discr))
8977 and then Is_Access_Type (Etype (Discr_Expr (J)))
8978 and then Is_Access_Constant (Etype (Discr_Expr (J)))
8981 ("constraint for discriminant& must be access to variable",
8986 Next_Discriminant (Discr);
8990 end Build_Discriminant_Constraints;
8992 ---------------------------------
8993 -- Build_Discriminated_Subtype --
8994 ---------------------------------
8996 procedure Build_Discriminated_Subtype
9000 Related_Nod : Node_Id;
9001 For_Access : Boolean := False)
9003 Has_Discrs : constant Boolean := Has_Discriminants (T);
9004 Constrained : constant Boolean :=
9006 and then not Is_Empty_Elmt_List (Elist)
9007 and then not Is_Class_Wide_Type (T))
9008 or else Is_Constrained (T);
9011 if Ekind (T) = E_Record_Type then
9013 Set_Ekind (Def_Id, E_Private_Subtype);
9014 Set_Is_For_Access_Subtype (Def_Id, True);
9016 Set_Ekind (Def_Id, E_Record_Subtype);
9019 -- Inherit preelaboration flag from base, for types for which it
9020 -- may have been set: records, private types, protected types.
9022 Set_Known_To_Have_Preelab_Init
9023 (Def_Id, Known_To_Have_Preelab_Init (T));
9025 elsif Ekind (T) = E_Task_Type then
9026 Set_Ekind (Def_Id, E_Task_Subtype);
9028 elsif Ekind (T) = E_Protected_Type then
9029 Set_Ekind (Def_Id, E_Protected_Subtype);
9030 Set_Known_To_Have_Preelab_Init
9031 (Def_Id, Known_To_Have_Preelab_Init (T));
9033 elsif Is_Private_Type (T) then
9034 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
9035 Set_Known_To_Have_Preelab_Init
9036 (Def_Id, Known_To_Have_Preelab_Init (T));
9038 -- Private subtypes may have private dependents
9040 Set_Private_Dependents (Def_Id, New_Elmt_List);
9042 elsif Is_Class_Wide_Type (T) then
9043 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
9046 -- Incomplete type. Attach subtype to list of dependents, to be
9047 -- completed with full view of parent type, unless is it the
9048 -- designated subtype of a record component within an init_proc.
9049 -- This last case arises for a component of an access type whose
9050 -- designated type is incomplete (e.g. a Taft Amendment type).
9051 -- The designated subtype is within an inner scope, and needs no
9052 -- elaboration, because only the access type is needed in the
9053 -- initialization procedure.
9055 Set_Ekind (Def_Id, Ekind (T));
9057 if For_Access and then Within_Init_Proc then
9060 Append_Elmt (Def_Id, Private_Dependents (T));
9064 Set_Etype (Def_Id, T);
9065 Init_Size_Align (Def_Id);
9066 Set_Has_Discriminants (Def_Id, Has_Discrs);
9067 Set_Is_Constrained (Def_Id, Constrained);
9069 Set_First_Entity (Def_Id, First_Entity (T));
9070 Set_Last_Entity (Def_Id, Last_Entity (T));
9071 Set_Has_Implicit_Dereference
9072 (Def_Id, Has_Implicit_Dereference (T));
9074 -- If the subtype is the completion of a private declaration, there may
9075 -- have been representation clauses for the partial view, and they must
9076 -- be preserved. Build_Derived_Type chains the inherited clauses with
9077 -- the ones appearing on the extension. If this comes from a subtype
9078 -- declaration, all clauses are inherited.
9080 if No (First_Rep_Item (Def_Id)) then
9081 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
9084 if Is_Tagged_Type (T) then
9085 Set_Is_Tagged_Type (Def_Id);
9086 Make_Class_Wide_Type (Def_Id);
9089 Set_Stored_Constraint (Def_Id, No_Elist);
9092 Set_Discriminant_Constraint (Def_Id, Elist);
9093 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
9096 if Is_Tagged_Type (T) then
9098 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
9099 -- concurrent record type (which has the list of primitive
9102 if Ada_Version >= Ada_2005
9103 and then Is_Concurrent_Type (T)
9105 Set_Corresponding_Record_Type (Def_Id,
9106 Corresponding_Record_Type (T));
9108 Set_Direct_Primitive_Operations (Def_Id,
9109 Direct_Primitive_Operations (T));
9112 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
9115 -- Subtypes introduced by component declarations do not need to be
9116 -- marked as delayed, and do not get freeze nodes, because the semantics
9117 -- verifies that the parents of the subtypes are frozen before the
9118 -- enclosing record is frozen.
9120 if not Is_Type (Scope (Def_Id)) then
9121 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
9123 if Is_Private_Type (T)
9124 and then Present (Full_View (T))
9126 Conditional_Delay (Def_Id, Full_View (T));
9128 Conditional_Delay (Def_Id, T);
9132 if Is_Record_Type (T) then
9133 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
9136 and then not Is_Empty_Elmt_List (Elist)
9137 and then not For_Access
9139 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
9140 elsif not For_Access then
9141 Set_Cloned_Subtype (Def_Id, T);
9144 end Build_Discriminated_Subtype;
9146 ---------------------------
9147 -- Build_Itype_Reference --
9148 ---------------------------
9150 procedure Build_Itype_Reference
9154 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
9157 -- Itype references are only created for use by the back-end
9159 if Inside_A_Generic then
9162 Set_Itype (IR, Ityp);
9163 Insert_After (Nod, IR);
9165 end Build_Itype_Reference;
9167 ------------------------
9168 -- Build_Scalar_Bound --
9169 ------------------------
9171 function Build_Scalar_Bound
9174 Der_T : Entity_Id) return Node_Id
9176 New_Bound : Entity_Id;
9179 -- Note: not clear why this is needed, how can the original bound
9180 -- be unanalyzed at this point? and if it is, what business do we
9181 -- have messing around with it? and why is the base type of the
9182 -- parent type the right type for the resolution. It probably is
9183 -- not. It is OK for the new bound we are creating, but not for
9184 -- the old one??? Still if it never happens, no problem.
9186 Analyze_And_Resolve (Bound, Base_Type (Par_T));
9188 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
9189 New_Bound := New_Copy (Bound);
9190 Set_Etype (New_Bound, Der_T);
9191 Set_Analyzed (New_Bound);
9193 elsif Is_Entity_Name (Bound) then
9194 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
9196 -- The following is almost certainly wrong. What business do we have
9197 -- relocating a node (Bound) that is presumably still attached to
9198 -- the tree elsewhere???
9201 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
9204 Set_Etype (New_Bound, Der_T);
9206 end Build_Scalar_Bound;
9208 --------------------------------
9209 -- Build_Underlying_Full_View --
9210 --------------------------------
9212 procedure Build_Underlying_Full_View
9217 Loc : constant Source_Ptr := Sloc (N);
9218 Subt : constant Entity_Id :=
9219 Make_Defining_Identifier
9220 (Loc, New_External_Name (Chars (Typ), 'S'));
9227 procedure Set_Discriminant_Name (Id : Node_Id);
9228 -- If the derived type has discriminants, they may rename discriminants
9229 -- of the parent. When building the full view of the parent, we need to
9230 -- recover the names of the original discriminants if the constraint is
9231 -- given by named associations.
9233 ---------------------------
9234 -- Set_Discriminant_Name --
9235 ---------------------------
9237 procedure Set_Discriminant_Name (Id : Node_Id) is
9241 Set_Original_Discriminant (Id, Empty);
9243 if Has_Discriminants (Typ) then
9244 Disc := First_Discriminant (Typ);
9245 while Present (Disc) loop
9246 if Chars (Disc) = Chars (Id)
9247 and then Present (Corresponding_Discriminant (Disc))
9249 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
9251 Next_Discriminant (Disc);
9254 end Set_Discriminant_Name;
9256 -- Start of processing for Build_Underlying_Full_View
9259 if Nkind (N) = N_Full_Type_Declaration then
9260 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
9262 elsif Nkind (N) = N_Subtype_Declaration then
9263 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
9265 elsif Nkind (N) = N_Component_Declaration then
9268 (Constraint (Subtype_Indication (Component_Definition (N))));
9271 raise Program_Error;
9274 C := First (Constraints (Constr));
9275 while Present (C) loop
9276 if Nkind (C) = N_Discriminant_Association then
9277 Id := First (Selector_Names (C));
9278 while Present (Id) loop
9279 Set_Discriminant_Name (Id);
9288 Make_Subtype_Declaration (Loc,
9289 Defining_Identifier => Subt,
9290 Subtype_Indication =>
9291 Make_Subtype_Indication (Loc,
9292 Subtype_Mark => New_Occurrence_Of (Par, Loc),
9293 Constraint => New_Copy_Tree (Constr)));
9295 -- If this is a component subtype for an outer itype, it is not
9296 -- a list member, so simply set the parent link for analysis: if
9297 -- the enclosing type does not need to be in a declarative list,
9298 -- neither do the components.
9300 if Is_List_Member (N)
9301 and then Nkind (N) /= N_Component_Declaration
9303 Insert_Before (N, Indic);
9305 Set_Parent (Indic, Parent (N));
9309 Set_Underlying_Full_View (Typ, Full_View (Subt));
9310 end Build_Underlying_Full_View;
9312 -------------------------------
9313 -- Check_Abstract_Overriding --
9314 -------------------------------
9316 procedure Check_Abstract_Overriding (T : Entity_Id) is
9317 Alias_Subp : Entity_Id;
9323 procedure Check_Pragma_Implemented (Subp : Entity_Id);
9324 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
9325 -- which has pragma Implemented already set. Check whether Subp's entity
9326 -- kind conforms to the implementation kind of the overridden routine.
9328 procedure Check_Pragma_Implemented
9330 Iface_Subp : Entity_Id);
9331 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
9332 -- Iface_Subp and both entities have pragma Implemented already set on
9333 -- them. Check whether the two implementation kinds are conforming.
9335 procedure Inherit_Pragma_Implemented
9337 Iface_Subp : Entity_Id);
9338 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
9339 -- subprogram Iface_Subp which has been marked by pragma Implemented.
9340 -- Propagate the implementation kind of Iface_Subp to Subp.
9342 ------------------------------
9343 -- Check_Pragma_Implemented --
9344 ------------------------------
9346 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
9347 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
9348 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
9349 Subp_Alias : constant Entity_Id := Alias (Subp);
9350 Contr_Typ : Entity_Id;
9351 Impl_Subp : Entity_Id;
9354 -- Subp must have an alias since it is a hidden entity used to link
9355 -- an interface subprogram to its overriding counterpart.
9357 pragma Assert (Present (Subp_Alias));
9359 -- Handle aliases to synchronized wrappers
9361 Impl_Subp := Subp_Alias;
9363 if Is_Primitive_Wrapper (Impl_Subp) then
9364 Impl_Subp := Wrapped_Entity (Impl_Subp);
9367 -- Extract the type of the controlling formal
9369 Contr_Typ := Etype (First_Formal (Subp_Alias));
9371 if Is_Concurrent_Record_Type (Contr_Typ) then
9372 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
9375 -- An interface subprogram whose implementation kind is By_Entry must
9376 -- be implemented by an entry.
9378 if Impl_Kind = Name_By_Entry
9379 and then Ekind (Impl_Subp) /= E_Entry
9381 Error_Msg_Node_2 := Iface_Alias;
9383 ("type & must implement abstract subprogram & with an entry",
9384 Subp_Alias, Contr_Typ);
9386 elsif Impl_Kind = Name_By_Protected_Procedure then
9388 -- An interface subprogram whose implementation kind is By_
9389 -- Protected_Procedure cannot be implemented by a primitive
9390 -- procedure of a task type.
9392 if Ekind (Contr_Typ) /= E_Protected_Type then
9393 Error_Msg_Node_2 := Contr_Typ;
9395 ("interface subprogram & cannot be implemented by a " &
9396 "primitive procedure of task type &", Subp_Alias,
9399 -- An interface subprogram whose implementation kind is By_
9400 -- Protected_Procedure must be implemented by a procedure.
9402 elsif Ekind (Impl_Subp) /= E_Procedure then
9403 Error_Msg_Node_2 := Iface_Alias;
9405 ("type & must implement abstract subprogram & with a " &
9406 "procedure", Subp_Alias, Contr_Typ);
9408 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9409 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9411 Error_Msg_Name_1 := Impl_Kind;
9413 ("overriding operation& must have synchronization%",
9417 -- If primitive has Optional synchronization, overriding operation
9418 -- must match if it has an explicit synchronization..
9420 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9421 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9423 Error_Msg_Name_1 := Impl_Kind;
9425 ("overriding operation& must have syncrhonization%",
9428 end Check_Pragma_Implemented;
9430 ------------------------------
9431 -- Check_Pragma_Implemented --
9432 ------------------------------
9434 procedure Check_Pragma_Implemented
9436 Iface_Subp : Entity_Id)
9438 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9439 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
9442 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
9443 -- and overriding subprogram are different. In general this is an
9444 -- error except when the implementation kind of the overridden
9445 -- subprograms is By_Any or Optional.
9447 if Iface_Kind /= Subp_Kind
9448 and then Iface_Kind /= Name_By_Any
9449 and then Iface_Kind /= Name_Optional
9451 if Iface_Kind = Name_By_Entry then
9453 ("incompatible implementation kind, overridden subprogram " &
9454 "is marked By_Entry", Subp);
9457 ("incompatible implementation kind, overridden subprogram " &
9458 "is marked By_Protected_Procedure", Subp);
9461 end Check_Pragma_Implemented;
9463 --------------------------------
9464 -- Inherit_Pragma_Implemented --
9465 --------------------------------
9467 procedure Inherit_Pragma_Implemented
9469 Iface_Subp : Entity_Id)
9471 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9472 Loc : constant Source_Ptr := Sloc (Subp);
9473 Impl_Prag : Node_Id;
9476 -- Since the implementation kind is stored as a representation item
9477 -- rather than a flag, create a pragma node.
9481 Chars => Name_Implemented,
9482 Pragma_Argument_Associations => New_List (
9483 Make_Pragma_Argument_Association (Loc,
9484 Expression => New_Occurrence_Of (Subp, Loc)),
9486 Make_Pragma_Argument_Association (Loc,
9487 Expression => Make_Identifier (Loc, Iface_Kind))));
9489 -- The pragma doesn't need to be analyzed because it is internally
9490 -- built. It is safe to directly register it as a rep item since we
9491 -- are only interested in the characters of the implementation kind.
9493 Record_Rep_Item (Subp, Impl_Prag);
9494 end Inherit_Pragma_Implemented;
9496 -- Start of processing for Check_Abstract_Overriding
9499 Op_List := Primitive_Operations (T);
9501 -- Loop to check primitive operations
9503 Elmt := First_Elmt (Op_List);
9504 while Present (Elmt) loop
9505 Subp := Node (Elmt);
9506 Alias_Subp := Alias (Subp);
9508 -- Inherited subprograms are identified by the fact that they do not
9509 -- come from source, and the associated source location is the
9510 -- location of the first subtype of the derived type.
9512 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
9513 -- subprograms that "require overriding".
9515 -- Special exception, do not complain about failure to override the
9516 -- stream routines _Input and _Output, as well as the primitive
9517 -- operations used in dispatching selects since we always provide
9518 -- automatic overridings for these subprograms.
9520 -- Also ignore this rule for convention CIL since .NET libraries
9521 -- do bizarre things with interfaces???
9523 -- The partial view of T may have been a private extension, for
9524 -- which inherited functions dispatching on result are abstract.
9525 -- If the full view is a null extension, there is no need for
9526 -- overriding in Ada 2005, but wrappers need to be built for them
9527 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
9529 if Is_Null_Extension (T)
9530 and then Has_Controlling_Result (Subp)
9531 and then Ada_Version >= Ada_2005
9532 and then Present (Alias_Subp)
9533 and then not Comes_From_Source (Subp)
9534 and then not Is_Abstract_Subprogram (Alias_Subp)
9535 and then not Is_Access_Type (Etype (Subp))
9539 -- Ada 2005 (AI-251): Internal entities of interfaces need no
9540 -- processing because this check is done with the aliased
9543 elsif Present (Interface_Alias (Subp)) then
9546 elsif (Is_Abstract_Subprogram (Subp)
9547 or else Requires_Overriding (Subp)
9549 (Has_Controlling_Result (Subp)
9550 and then Present (Alias_Subp)
9551 and then not Comes_From_Source (Subp)
9552 and then Sloc (Subp) = Sloc (First_Subtype (T))))
9553 and then not Is_TSS (Subp, TSS_Stream_Input)
9554 and then not Is_TSS (Subp, TSS_Stream_Output)
9555 and then not Is_Abstract_Type (T)
9556 and then Convention (T) /= Convention_CIL
9557 and then not Is_Predefined_Interface_Primitive (Subp)
9559 -- Ada 2005 (AI-251): Do not consider hidden entities associated
9560 -- with abstract interface types because the check will be done
9561 -- with the aliased entity (otherwise we generate a duplicated
9564 and then not Present (Interface_Alias (Subp))
9566 if Present (Alias_Subp) then
9568 -- Only perform the check for a derived subprogram when the
9569 -- type has an explicit record extension. This avoids incorrect
9570 -- flagging of abstract subprograms for the case of a type
9571 -- without an extension that is derived from a formal type
9572 -- with a tagged actual (can occur within a private part).
9574 -- Ada 2005 (AI-391): In the case of an inherited function with
9575 -- a controlling result of the type, the rule does not apply if
9576 -- the type is a null extension (unless the parent function
9577 -- itself is abstract, in which case the function must still be
9578 -- be overridden). The expander will generate an overriding
9579 -- wrapper function calling the parent subprogram (see
9580 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
9582 Type_Def := Type_Definition (Parent (T));
9584 if Nkind (Type_Def) = N_Derived_Type_Definition
9585 and then Present (Record_Extension_Part (Type_Def))
9587 (Ada_Version < Ada_2005
9588 or else not Is_Null_Extension (T)
9589 or else Ekind (Subp) = E_Procedure
9590 or else not Has_Controlling_Result (Subp)
9591 or else Is_Abstract_Subprogram (Alias_Subp)
9592 or else Requires_Overriding (Subp)
9593 or else Is_Access_Type (Etype (Subp)))
9595 -- Avoid reporting error in case of abstract predefined
9596 -- primitive inherited from interface type because the
9597 -- body of internally generated predefined primitives
9598 -- of tagged types are generated later by Freeze_Type
9600 if Is_Interface (Root_Type (T))
9601 and then Is_Abstract_Subprogram (Subp)
9602 and then Is_Predefined_Dispatching_Operation (Subp)
9603 and then not Comes_From_Source (Ultimate_Alias (Subp))
9609 ("type must be declared abstract or & overridden",
9612 -- Traverse the whole chain of aliased subprograms to
9613 -- complete the error notification. This is especially
9614 -- useful for traceability of the chain of entities when
9615 -- the subprogram corresponds with an interface
9616 -- subprogram (which may be defined in another package).
9618 if Present (Alias_Subp) then
9624 while Present (Alias (E)) loop
9626 -- Avoid reporting redundant errors on entities
9627 -- inherited from interfaces
9629 if Sloc (E) /= Sloc (T) then
9630 Error_Msg_Sloc := Sloc (E);
9632 ("\& has been inherited #", T, Subp);
9638 Error_Msg_Sloc := Sloc (E);
9640 -- AI05-0068: report if there is an overriding
9641 -- non-abstract subprogram that is invisible.
9644 and then not Is_Abstract_Subprogram (E)
9647 ("\& subprogram# is not visible",
9652 ("\& has been inherited from subprogram #",
9659 -- Ada 2005 (AI-345): Protected or task type implementing
9660 -- abstract interfaces.
9662 elsif Is_Concurrent_Record_Type (T)
9663 and then Present (Interfaces (T))
9665 -- If an inherited subprogram is implemented by a protected
9666 -- procedure or an entry, then the first parameter of the
9667 -- inherited subprogram shall be of mode OUT or IN OUT, or
9668 -- an access-to-variable parameter (RM 9.4(11.9/3))
9670 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
9671 and then Ekind (First_Formal (Subp)) = E_In_Parameter
9672 and then Ekind (Subp) /= E_Function
9673 and then not Is_Predefined_Dispatching_Operation (Subp)
9675 Error_Msg_PT (T, Subp);
9677 -- Some other kind of overriding failure
9681 ("interface subprogram & must be overridden",
9684 -- Examine primitive operations of synchronized type,
9685 -- to find homonyms that have the wrong profile.
9692 First_Entity (Corresponding_Concurrent_Type (T));
9693 while Present (Prim) loop
9694 if Chars (Prim) = Chars (Subp) then
9696 ("profile is not type conformant with "
9697 & "prefixed view profile of "
9698 & "inherited operation&", Prim, Subp);
9708 Error_Msg_Node_2 := T;
9710 ("abstract subprogram& not allowed for type&", Subp);
9712 -- Also post unconditional warning on the type (unconditional
9713 -- so that if there are more than one of these cases, we get
9714 -- them all, and not just the first one).
9716 Error_Msg_Node_2 := Subp;
9717 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
9721 -- Ada 2012 (AI05-0030): Perform checks related to pragma Implemented
9723 -- Subp is an expander-generated procedure which maps an interface
9724 -- alias to a protected wrapper. The interface alias is flagged by
9725 -- pragma Implemented. Ensure that Subp is a procedure when the
9726 -- implementation kind is By_Protected_Procedure or an entry when
9729 if Ada_Version >= Ada_2012
9730 and then Is_Hidden (Subp)
9731 and then Present (Interface_Alias (Subp))
9732 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
9734 Check_Pragma_Implemented (Subp);
9737 -- Subp is an interface primitive which overrides another interface
9738 -- primitive marked with pragma Implemented.
9740 if Ada_Version >= Ada_2012
9741 and then Present (Overridden_Operation (Subp))
9742 and then Has_Rep_Pragma
9743 (Overridden_Operation (Subp), Name_Implemented)
9745 -- If the overriding routine is also marked by Implemented, check
9746 -- that the two implementation kinds are conforming.
9748 if Has_Rep_Pragma (Subp, Name_Implemented) then
9749 Check_Pragma_Implemented
9751 Iface_Subp => Overridden_Operation (Subp));
9753 -- Otherwise the overriding routine inherits the implementation
9754 -- kind from the overridden subprogram.
9757 Inherit_Pragma_Implemented
9759 Iface_Subp => Overridden_Operation (Subp));
9763 -- If the operation is a wrapper for a synchronized primitive, it
9764 -- may be called indirectly through a dispatching select. We assume
9765 -- that it will be referenced elsewhere indirectly, and suppress
9766 -- warnings about an unused entity.
9768 if Is_Primitive_Wrapper (Subp)
9769 and then Present (Wrapped_Entity (Subp))
9771 Set_Referenced (Wrapped_Entity (Subp));
9776 end Check_Abstract_Overriding;
9778 ------------------------------------------------
9779 -- Check_Access_Discriminant_Requires_Limited --
9780 ------------------------------------------------
9782 procedure Check_Access_Discriminant_Requires_Limited
9787 -- A discriminant_specification for an access discriminant shall appear
9788 -- only in the declaration for a task or protected type, or for a type
9789 -- with the reserved word 'limited' in its definition or in one of its
9790 -- ancestors (RM 3.7(10)).
9792 -- AI-0063: The proper condition is that type must be immutably limited,
9793 -- or else be a partial view.
9795 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
9796 if Is_Limited_View (Current_Scope)
9798 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
9799 and then Limited_Present (Parent (Current_Scope)))
9805 ("access discriminants allowed only for limited types", Loc);
9808 end Check_Access_Discriminant_Requires_Limited;
9810 -----------------------------------
9811 -- Check_Aliased_Component_Types --
9812 -----------------------------------
9814 procedure Check_Aliased_Component_Types (T : Entity_Id) is
9818 -- ??? Also need to check components of record extensions, but not
9819 -- components of protected types (which are always limited).
9821 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
9822 -- types to be unconstrained. This is safe because it is illegal to
9823 -- create access subtypes to such types with explicit discriminant
9826 if not Is_Limited_Type (T) then
9827 if Ekind (T) = E_Record_Type then
9828 C := First_Component (T);
9829 while Present (C) loop
9831 and then Has_Discriminants (Etype (C))
9832 and then not Is_Constrained (Etype (C))
9833 and then not In_Instance_Body
9834 and then Ada_Version < Ada_2005
9837 ("aliased component must be constrained (RM 3.6(11))",
9844 elsif Ekind (T) = E_Array_Type then
9845 if Has_Aliased_Components (T)
9846 and then Has_Discriminants (Component_Type (T))
9847 and then not Is_Constrained (Component_Type (T))
9848 and then not In_Instance_Body
9849 and then Ada_Version < Ada_2005
9852 ("aliased component type must be constrained (RM 3.6(11))",
9857 end Check_Aliased_Component_Types;
9859 ----------------------
9860 -- Check_Completion --
9861 ----------------------
9863 procedure Check_Completion (Body_Id : Node_Id := Empty) is
9866 procedure Post_Error;
9867 -- Post error message for lack of completion for entity E
9873 procedure Post_Error is
9875 procedure Missing_Body;
9876 -- Output missing body message
9882 procedure Missing_Body is
9884 -- Spec is in same unit, so we can post on spec
9886 if In_Same_Source_Unit (Body_Id, E) then
9887 Error_Msg_N ("missing body for &", E);
9889 -- Spec is in a separate unit, so we have to post on the body
9892 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
9896 -- Start of processing for Post_Error
9899 if not Comes_From_Source (E) then
9901 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
9902 -- It may be an anonymous protected type created for a
9903 -- single variable. Post error on variable, if present.
9909 Var := First_Entity (Current_Scope);
9910 while Present (Var) loop
9911 exit when Etype (Var) = E
9912 and then Comes_From_Source (Var);
9917 if Present (Var) then
9924 -- If a generated entity has no completion, then either previous
9925 -- semantic errors have disabled the expansion phase, or else we had
9926 -- missing subunits, or else we are compiling without expansion,
9927 -- or else something is very wrong.
9929 if not Comes_From_Source (E) then
9931 (Serious_Errors_Detected > 0
9932 or else Configurable_Run_Time_Violations > 0
9933 or else Subunits_Missing
9934 or else not Expander_Active);
9937 -- Here for source entity
9940 -- Here if no body to post the error message, so we post the error
9941 -- on the declaration that has no completion. This is not really
9942 -- the right place to post it, think about this later ???
9944 if No (Body_Id) then
9947 ("missing full declaration for }", Parent (E), E);
9949 Error_Msg_NE ("missing body for &", Parent (E), E);
9952 -- Package body has no completion for a declaration that appears
9953 -- in the corresponding spec. Post error on the body, with a
9954 -- reference to the non-completed declaration.
9957 Error_Msg_Sloc := Sloc (E);
9960 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
9962 elsif Is_Overloadable (E)
9963 and then Current_Entity_In_Scope (E) /= E
9965 -- It may be that the completion is mistyped and appears as
9966 -- a distinct overloading of the entity.
9969 Candidate : constant Entity_Id :=
9970 Current_Entity_In_Scope (E);
9971 Decl : constant Node_Id :=
9972 Unit_Declaration_Node (Candidate);
9975 if Is_Overloadable (Candidate)
9976 and then Ekind (Candidate) = Ekind (E)
9977 and then Nkind (Decl) = N_Subprogram_Body
9978 and then Acts_As_Spec (Decl)
9980 Check_Type_Conformant (Candidate, E);
9994 -- Start of processing for Check_Completion
9997 E := First_Entity (Current_Scope);
9998 while Present (E) loop
9999 if Is_Intrinsic_Subprogram (E) then
10002 -- The following situation requires special handling: a child unit
10003 -- that appears in the context clause of the body of its parent:
10005 -- procedure Parent.Child (...);
10007 -- with Parent.Child;
10008 -- package body Parent is
10010 -- Here Parent.Child appears as a local entity, but should not be
10011 -- flagged as requiring completion, because it is a compilation
10014 -- Ignore missing completion for a subprogram that does not come from
10015 -- source (including the _Call primitive operation of RAS types,
10016 -- which has to have the flag Comes_From_Source for other purposes):
10017 -- we assume that the expander will provide the missing completion.
10018 -- In case of previous errors, other expansion actions that provide
10019 -- bodies for null procedures with not be invoked, so inhibit message
10022 -- Note that E_Operator is not in the list that follows, because
10023 -- this kind is reserved for predefined operators, that are
10024 -- intrinsic and do not need completion.
10026 elsif Ekind (E) = E_Function
10027 or else Ekind (E) = E_Procedure
10028 or else Ekind (E) = E_Generic_Function
10029 or else Ekind (E) = E_Generic_Procedure
10031 if Has_Completion (E) then
10034 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
10037 elsif Is_Subprogram (E)
10038 and then (not Comes_From_Source (E)
10039 or else Chars (E) = Name_uCall)
10044 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
10048 elsif Nkind (Parent (E)) = N_Procedure_Specification
10049 and then Null_Present (Parent (E))
10050 and then Serious_Errors_Detected > 0
10058 elsif Is_Entry (E) then
10059 if not Has_Completion (E) and then
10060 (Ekind (Scope (E)) = E_Protected_Object
10061 or else Ekind (Scope (E)) = E_Protected_Type)
10066 elsif Is_Package_Or_Generic_Package (E) then
10067 if Unit_Requires_Body (E) then
10068 if not Has_Completion (E)
10069 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
10075 elsif not Is_Child_Unit (E) then
10076 May_Need_Implicit_Body (E);
10079 -- A formal incomplete type (Ada 2012) does not require a completion;
10080 -- other incomplete type declarations do.
10082 elsif Ekind (E) = E_Incomplete_Type
10083 and then No (Underlying_Type (E))
10084 and then not Is_Generic_Type (E)
10088 elsif (Ekind (E) = E_Task_Type or else
10089 Ekind (E) = E_Protected_Type)
10090 and then not Has_Completion (E)
10094 -- A single task declared in the current scope is a constant, verify
10095 -- that the body of its anonymous type is in the same scope. If the
10096 -- task is defined elsewhere, this may be a renaming declaration for
10097 -- which no completion is needed.
10099 elsif Ekind (E) = E_Constant
10100 and then Ekind (Etype (E)) = E_Task_Type
10101 and then not Has_Completion (Etype (E))
10102 and then Scope (Etype (E)) = Current_Scope
10106 elsif Ekind (E) = E_Protected_Object
10107 and then not Has_Completion (Etype (E))
10111 elsif Ekind (E) = E_Record_Type then
10112 if Is_Tagged_Type (E) then
10113 Check_Abstract_Overriding (E);
10114 Check_Conventions (E);
10117 Check_Aliased_Component_Types (E);
10119 elsif Ekind (E) = E_Array_Type then
10120 Check_Aliased_Component_Types (E);
10126 end Check_Completion;
10128 ------------------------------------
10129 -- Check_CPP_Type_Has_No_Defaults --
10130 ------------------------------------
10132 procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id) is
10133 Tdef : constant Node_Id := Type_Definition (Declaration_Node (T));
10138 -- Obtain the component list
10140 if Nkind (Tdef) = N_Record_Definition then
10141 Clist := Component_List (Tdef);
10142 else pragma Assert (Nkind (Tdef) = N_Derived_Type_Definition);
10143 Clist := Component_List (Record_Extension_Part (Tdef));
10146 -- Check all components to ensure no default expressions
10148 if Present (Clist) then
10149 Comp := First (Component_Items (Clist));
10150 while Present (Comp) loop
10151 if Present (Expression (Comp)) then
10153 ("component of imported 'C'P'P type cannot have "
10154 & "default expression", Expression (Comp));
10160 end Check_CPP_Type_Has_No_Defaults;
10162 ----------------------------
10163 -- Check_Delta_Expression --
10164 ----------------------------
10166 procedure Check_Delta_Expression (E : Node_Id) is
10168 if not (Is_Real_Type (Etype (E))) then
10169 Wrong_Type (E, Any_Real);
10171 elsif not Is_OK_Static_Expression (E) then
10172 Flag_Non_Static_Expr
10173 ("non-static expression used for delta value!", E);
10175 elsif not UR_Is_Positive (Expr_Value_R (E)) then
10176 Error_Msg_N ("delta expression must be positive", E);
10182 -- If any of above errors occurred, then replace the incorrect
10183 -- expression by the real 0.1, which should prevent further errors.
10186 Make_Real_Literal (Sloc (E), Ureal_Tenth));
10187 Analyze_And_Resolve (E, Standard_Float);
10188 end Check_Delta_Expression;
10190 -----------------------------
10191 -- Check_Digits_Expression --
10192 -----------------------------
10194 procedure Check_Digits_Expression (E : Node_Id) is
10196 if not (Is_Integer_Type (Etype (E))) then
10197 Wrong_Type (E, Any_Integer);
10199 elsif not Is_OK_Static_Expression (E) then
10200 Flag_Non_Static_Expr
10201 ("non-static expression used for digits value!", E);
10203 elsif Expr_Value (E) <= 0 then
10204 Error_Msg_N ("digits value must be greater than zero", E);
10210 -- If any of above errors occurred, then replace the incorrect
10211 -- expression by the integer 1, which should prevent further errors.
10213 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
10214 Analyze_And_Resolve (E, Standard_Integer);
10216 end Check_Digits_Expression;
10218 --------------------------
10219 -- Check_Initialization --
10220 --------------------------
10222 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
10224 if Is_Limited_Type (T)
10225 and then not In_Instance
10226 and then not In_Inlined_Body
10228 if not OK_For_Limited_Init (T, Exp) then
10230 -- In GNAT mode, this is just a warning, to allow it to be evilly
10231 -- turned off. Otherwise it is a real error.
10235 ("??cannot initialize entities of limited type!", Exp);
10237 elsif Ada_Version < Ada_2005 then
10239 -- The side effect removal machinery may generate illegal Ada
10240 -- code to avoid the usage of access types and 'reference in
10241 -- SPARK mode. Since this is legal code with respect to theorem
10242 -- proving, do not emit the error.
10245 and then Nkind (Exp) = N_Function_Call
10246 and then Nkind (Parent (Exp)) = N_Object_Declaration
10247 and then not Comes_From_Source
10248 (Defining_Identifier (Parent (Exp)))
10254 ("cannot initialize entities of limited type", Exp);
10255 Explain_Limited_Type (T, Exp);
10259 -- Specialize error message according to kind of illegal
10260 -- initial expression.
10262 if Nkind (Exp) = N_Type_Conversion
10263 and then Nkind (Expression (Exp)) = N_Function_Call
10266 ("illegal context for call"
10267 & " to function with limited result", Exp);
10271 ("initialization of limited object requires aggregate "
10272 & "or function call", Exp);
10277 end Check_Initialization;
10279 ----------------------
10280 -- Check_Interfaces --
10281 ----------------------
10283 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
10284 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
10287 Iface_Def : Node_Id;
10288 Iface_Typ : Entity_Id;
10289 Parent_Node : Node_Id;
10291 Is_Task : Boolean := False;
10292 -- Set True if parent type or any progenitor is a task interface
10294 Is_Protected : Boolean := False;
10295 -- Set True if parent type or any progenitor is a protected interface
10297 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
10298 -- Check that a progenitor is compatible with declaration.
10299 -- Error is posted on Error_Node.
10305 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
10306 Iface_Id : constant Entity_Id :=
10307 Defining_Identifier (Parent (Iface_Def));
10308 Type_Def : Node_Id;
10311 if Nkind (N) = N_Private_Extension_Declaration then
10314 Type_Def := Type_Definition (N);
10317 if Is_Task_Interface (Iface_Id) then
10320 elsif Is_Protected_Interface (Iface_Id) then
10321 Is_Protected := True;
10324 if Is_Synchronized_Interface (Iface_Id) then
10326 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
10327 -- extension derived from a synchronized interface must explicitly
10328 -- be declared synchronized, because the full view will be a
10329 -- synchronized type.
10331 if Nkind (N) = N_Private_Extension_Declaration then
10332 if not Synchronized_Present (N) then
10334 ("private extension of& must be explicitly synchronized",
10338 -- However, by 3.9.4(16/2), a full type that is a record extension
10339 -- is never allowed to derive from a synchronized interface (note
10340 -- that interfaces must be excluded from this check, because those
10341 -- are represented by derived type definitions in some cases).
10343 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
10344 and then not Interface_Present (Type_Definition (N))
10346 Error_Msg_N ("record extension cannot derive from synchronized"
10347 & " interface", Error_Node);
10351 -- Check that the characteristics of the progenitor are compatible
10352 -- with the explicit qualifier in the declaration.
10353 -- The check only applies to qualifiers that come from source.
10354 -- Limited_Present also appears in the declaration of corresponding
10355 -- records, and the check does not apply to them.
10357 if Limited_Present (Type_Def)
10359 Is_Concurrent_Record_Type (Defining_Identifier (N))
10361 if Is_Limited_Interface (Parent_Type)
10362 and then not Is_Limited_Interface (Iface_Id)
10365 ("progenitor& must be limited interface",
10366 Error_Node, Iface_Id);
10369 (Task_Present (Iface_Def)
10370 or else Protected_Present (Iface_Def)
10371 or else Synchronized_Present (Iface_Def))
10372 and then Nkind (N) /= N_Private_Extension_Declaration
10373 and then not Error_Posted (N)
10376 ("progenitor& must be limited interface",
10377 Error_Node, Iface_Id);
10380 -- Protected interfaces can only inherit from limited, synchronized
10381 -- or protected interfaces.
10383 elsif Nkind (N) = N_Full_Type_Declaration
10384 and then Protected_Present (Type_Def)
10386 if Limited_Present (Iface_Def)
10387 or else Synchronized_Present (Iface_Def)
10388 or else Protected_Present (Iface_Def)
10392 elsif Task_Present (Iface_Def) then
10393 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
10394 & " from task interface", Error_Node);
10397 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
10398 & " from non-limited interface", Error_Node);
10401 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
10402 -- limited and synchronized.
10404 elsif Synchronized_Present (Type_Def) then
10405 if Limited_Present (Iface_Def)
10406 or else Synchronized_Present (Iface_Def)
10410 elsif Protected_Present (Iface_Def)
10411 and then Nkind (N) /= N_Private_Extension_Declaration
10413 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
10414 & " from protected interface", Error_Node);
10416 elsif Task_Present (Iface_Def)
10417 and then Nkind (N) /= N_Private_Extension_Declaration
10419 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
10420 & " from task interface", Error_Node);
10422 elsif not Is_Limited_Interface (Iface_Id) then
10423 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
10424 & " from non-limited interface", Error_Node);
10427 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
10428 -- synchronized or task interfaces.
10430 elsif Nkind (N) = N_Full_Type_Declaration
10431 and then Task_Present (Type_Def)
10433 if Limited_Present (Iface_Def)
10434 or else Synchronized_Present (Iface_Def)
10435 or else Task_Present (Iface_Def)
10439 elsif Protected_Present (Iface_Def) then
10440 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
10441 & " protected interface", Error_Node);
10444 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
10445 & " non-limited interface", Error_Node);
10450 -- Start of processing for Check_Interfaces
10453 if Is_Interface (Parent_Type) then
10454 if Is_Task_Interface (Parent_Type) then
10457 elsif Is_Protected_Interface (Parent_Type) then
10458 Is_Protected := True;
10462 if Nkind (N) = N_Private_Extension_Declaration then
10464 -- Check that progenitors are compatible with declaration
10466 Iface := First (Interface_List (Def));
10467 while Present (Iface) loop
10468 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
10470 Parent_Node := Parent (Base_Type (Iface_Typ));
10471 Iface_Def := Type_Definition (Parent_Node);
10473 if not Is_Interface (Iface_Typ) then
10474 Diagnose_Interface (Iface, Iface_Typ);
10477 Check_Ifaces (Iface_Def, Iface);
10483 if Is_Task and Is_Protected then
10485 ("type cannot derive from task and protected interface", N);
10491 -- Full type declaration of derived type.
10492 -- Check compatibility with parent if it is interface type
10494 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
10495 and then Is_Interface (Parent_Type)
10497 Parent_Node := Parent (Parent_Type);
10499 -- More detailed checks for interface varieties
10502 (Iface_Def => Type_Definition (Parent_Node),
10503 Error_Node => Subtype_Indication (Type_Definition (N)));
10506 Iface := First (Interface_List (Def));
10507 while Present (Iface) loop
10508 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
10510 Parent_Node := Parent (Base_Type (Iface_Typ));
10511 Iface_Def := Type_Definition (Parent_Node);
10513 if not Is_Interface (Iface_Typ) then
10514 Diagnose_Interface (Iface, Iface_Typ);
10517 -- "The declaration of a specific descendant of an interface
10518 -- type freezes the interface type" RM 13.14
10520 Freeze_Before (N, Iface_Typ);
10521 Check_Ifaces (Iface_Def, Error_Node => Iface);
10527 if Is_Task and Is_Protected then
10529 ("type cannot derive from task and protected interface", N);
10531 end Check_Interfaces;
10533 ------------------------------------
10534 -- Check_Or_Process_Discriminants --
10535 ------------------------------------
10537 -- If an incomplete or private type declaration was already given for the
10538 -- type, the discriminants may have already been processed if they were
10539 -- present on the incomplete declaration. In this case a full conformance
10540 -- check has been performed in Find_Type_Name, and we then recheck here
10541 -- some properties that can't be checked on the partial view alone.
10542 -- Otherwise we call Process_Discriminants.
10544 procedure Check_Or_Process_Discriminants
10547 Prev : Entity_Id := Empty)
10550 if Has_Discriminants (T) then
10552 -- Discriminants are already set on T if they were already present
10553 -- on the partial view. Make them visible to component declarations.
10557 -- Discriminant on T (full view) referencing expr on partial view
10559 Prev_D : Entity_Id;
10560 -- Entity of corresponding discriminant on partial view
10563 -- Discriminant specification for full view, expression is the
10564 -- syntactic copy on full view (which has been checked for
10565 -- conformance with partial view), only used here to post error
10569 D := First_Discriminant (T);
10570 New_D := First (Discriminant_Specifications (N));
10571 while Present (D) loop
10572 Prev_D := Current_Entity (D);
10573 Set_Current_Entity (D);
10574 Set_Is_Immediately_Visible (D);
10575 Set_Homonym (D, Prev_D);
10577 -- Handle the case where there is an untagged partial view and
10578 -- the full view is tagged: must disallow discriminants with
10579 -- defaults, unless compiling for Ada 2012, which allows a
10580 -- limited tagged type to have defaulted discriminants (see
10581 -- AI05-0214). However, suppress error here if it was already
10582 -- reported on the default expression of the partial view.
10584 if Is_Tagged_Type (T)
10585 and then Present (Expression (Parent (D)))
10586 and then (not Is_Limited_Type (Current_Scope)
10587 or else Ada_Version < Ada_2012)
10588 and then not Error_Posted (Expression (Parent (D)))
10590 if Ada_Version >= Ada_2012 then
10592 ("discriminants of nonlimited tagged type cannot have"
10594 Expression (New_D));
10597 ("discriminants of tagged type cannot have defaults",
10598 Expression (New_D));
10602 -- Ada 2005 (AI-230): Access discriminant allowed in
10603 -- non-limited record types.
10605 if Ada_Version < Ada_2005 then
10607 -- This restriction gets applied to the full type here. It
10608 -- has already been applied earlier to the partial view.
10610 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
10613 Next_Discriminant (D);
10618 elsif Present (Discriminant_Specifications (N)) then
10619 Process_Discriminants (N, Prev);
10621 end Check_Or_Process_Discriminants;
10623 ----------------------
10624 -- Check_Real_Bound --
10625 ----------------------
10627 procedure Check_Real_Bound (Bound : Node_Id) is
10629 if not Is_Real_Type (Etype (Bound)) then
10631 ("bound in real type definition must be of real type", Bound);
10633 elsif not Is_OK_Static_Expression (Bound) then
10634 Flag_Non_Static_Expr
10635 ("non-static expression used for real type bound!", Bound);
10642 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
10644 Resolve (Bound, Standard_Float);
10645 end Check_Real_Bound;
10647 ------------------------------
10648 -- Complete_Private_Subtype --
10649 ------------------------------
10651 procedure Complete_Private_Subtype
10654 Full_Base : Entity_Id;
10655 Related_Nod : Node_Id)
10657 Save_Next_Entity : Entity_Id;
10658 Save_Homonym : Entity_Id;
10661 -- Set semantic attributes for (implicit) private subtype completion.
10662 -- If the full type has no discriminants, then it is a copy of the full
10663 -- view of the base. Otherwise, it is a subtype of the base with a
10664 -- possible discriminant constraint. Save and restore the original
10665 -- Next_Entity field of full to ensure that the calls to Copy_Node
10666 -- do not corrupt the entity chain.
10668 -- Note that the type of the full view is the same entity as the type of
10669 -- the partial view. In this fashion, the subtype has access to the
10670 -- correct view of the parent.
10672 Save_Next_Entity := Next_Entity (Full);
10673 Save_Homonym := Homonym (Priv);
10675 case Ekind (Full_Base) is
10676 when E_Record_Type |
10682 Copy_Node (Priv, Full);
10684 Set_Has_Discriminants
10685 (Full, Has_Discriminants (Full_Base));
10686 Set_Has_Unknown_Discriminants
10687 (Full, Has_Unknown_Discriminants (Full_Base));
10688 Set_First_Entity (Full, First_Entity (Full_Base));
10689 Set_Last_Entity (Full, Last_Entity (Full_Base));
10691 -- If the underlying base type is constrained, we know that the
10692 -- full view of the subtype is constrained as well (the converse
10693 -- is not necessarily true).
10695 if Is_Constrained (Full_Base) then
10696 Set_Is_Constrained (Full);
10700 Copy_Node (Full_Base, Full);
10702 Set_Chars (Full, Chars (Priv));
10703 Conditional_Delay (Full, Priv);
10704 Set_Sloc (Full, Sloc (Priv));
10707 Set_Next_Entity (Full, Save_Next_Entity);
10708 Set_Homonym (Full, Save_Homonym);
10709 Set_Associated_Node_For_Itype (Full, Related_Nod);
10711 -- Set common attributes for all subtypes: kind, convention, etc.
10713 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
10714 Set_Convention (Full, Convention (Full_Base));
10716 -- The Etype of the full view is inconsistent. Gigi needs to see the
10717 -- structural full view, which is what the current scheme gives:
10718 -- the Etype of the full view is the etype of the full base. However,
10719 -- if the full base is a derived type, the full view then looks like
10720 -- a subtype of the parent, not a subtype of the full base. If instead
10723 -- Set_Etype (Full, Full_Base);
10725 -- then we get inconsistencies in the front-end (confusion between
10726 -- views). Several outstanding bugs are related to this ???
10728 Set_Is_First_Subtype (Full, False);
10729 Set_Scope (Full, Scope (Priv));
10730 Set_Size_Info (Full, Full_Base);
10731 Set_RM_Size (Full, RM_Size (Full_Base));
10732 Set_Is_Itype (Full);
10734 -- A subtype of a private-type-without-discriminants, whose full-view
10735 -- has discriminants with default expressions, is not constrained.
10737 if not Has_Discriminants (Priv) then
10738 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
10740 if Has_Discriminants (Full_Base) then
10741 Set_Discriminant_Constraint
10742 (Full, Discriminant_Constraint (Full_Base));
10744 -- The partial view may have been indefinite, the full view
10747 Set_Has_Unknown_Discriminants
10748 (Full, Has_Unknown_Discriminants (Full_Base));
10752 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
10753 Set_Depends_On_Private (Full, Has_Private_Component (Full));
10755 -- Freeze the private subtype entity if its parent is delayed, and not
10756 -- already frozen. We skip this processing if the type is an anonymous
10757 -- subtype of a record component, or is the corresponding record of a
10758 -- protected type, since ???
10760 if not Is_Type (Scope (Full)) then
10761 Set_Has_Delayed_Freeze (Full,
10762 Has_Delayed_Freeze (Full_Base)
10763 and then (not Is_Frozen (Full_Base)));
10766 Set_Freeze_Node (Full, Empty);
10767 Set_Is_Frozen (Full, False);
10768 Set_Full_View (Priv, Full);
10770 if Has_Discriminants (Full) then
10771 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
10772 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
10774 if Has_Unknown_Discriminants (Full) then
10775 Set_Discriminant_Constraint (Full, No_Elist);
10779 if Ekind (Full_Base) = E_Record_Type
10780 and then Has_Discriminants (Full_Base)
10781 and then Has_Discriminants (Priv) -- might not, if errors
10782 and then not Has_Unknown_Discriminants (Priv)
10783 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
10785 Create_Constrained_Components
10786 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
10788 -- If the full base is itself derived from private, build a congruent
10789 -- subtype of its underlying type, for use by the back end. For a
10790 -- constrained record component, the declaration cannot be placed on
10791 -- the component list, but it must nevertheless be built an analyzed, to
10792 -- supply enough information for Gigi to compute the size of component.
10794 elsif Ekind (Full_Base) in Private_Kind
10795 and then Is_Derived_Type (Full_Base)
10796 and then Has_Discriminants (Full_Base)
10797 and then (Ekind (Current_Scope) /= E_Record_Subtype)
10799 if not Is_Itype (Priv)
10801 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
10803 Build_Underlying_Full_View
10804 (Parent (Priv), Full, Etype (Full_Base));
10806 elsif Nkind (Related_Nod) = N_Component_Declaration then
10807 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
10810 elsif Is_Record_Type (Full_Base) then
10812 -- Show Full is simply a renaming of Full_Base
10814 Set_Cloned_Subtype (Full, Full_Base);
10817 -- It is unsafe to share the bounds of a scalar type, because the Itype
10818 -- is elaborated on demand, and if a bound is non-static then different
10819 -- orders of elaboration in different units will lead to different
10820 -- external symbols.
10822 if Is_Scalar_Type (Full_Base) then
10823 Set_Scalar_Range (Full,
10824 Make_Range (Sloc (Related_Nod),
10826 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
10828 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
10830 -- This completion inherits the bounds of the full parent, but if
10831 -- the parent is an unconstrained floating point type, so is the
10834 if Is_Floating_Point_Type (Full_Base) then
10835 Set_Includes_Infinities
10836 (Scalar_Range (Full), Has_Infinities (Full_Base));
10840 -- ??? It seems that a lot of fields are missing that should be copied
10841 -- from Full_Base to Full. Here are some that are introduced in a
10842 -- non-disruptive way but a cleanup is necessary.
10844 if Is_Tagged_Type (Full_Base) then
10845 Set_Is_Tagged_Type (Full);
10846 Set_Direct_Primitive_Operations (Full,
10847 Direct_Primitive_Operations (Full_Base));
10849 -- Inherit class_wide type of full_base in case the partial view was
10850 -- not tagged. Otherwise it has already been created when the private
10851 -- subtype was analyzed.
10853 if No (Class_Wide_Type (Full)) then
10854 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
10857 -- If this is a subtype of a protected or task type, constrain its
10858 -- corresponding record, unless this is a subtype without constraints,
10859 -- i.e. a simple renaming as with an actual subtype in an instance.
10861 elsif Is_Concurrent_Type (Full_Base) then
10862 if Has_Discriminants (Full)
10863 and then Present (Corresponding_Record_Type (Full_Base))
10865 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
10867 Set_Corresponding_Record_Type (Full,
10868 Constrain_Corresponding_Record
10869 (Full, Corresponding_Record_Type (Full_Base),
10870 Related_Nod, Full_Base));
10873 Set_Corresponding_Record_Type (Full,
10874 Corresponding_Record_Type (Full_Base));
10878 -- Link rep item chain, and also setting of Has_Predicates from private
10879 -- subtype to full subtype, since we will need these on the full subtype
10880 -- to create the predicate function. Note that the full subtype may
10881 -- already have rep items, inherited from the full view of the base
10882 -- type, so we must be sure not to overwrite these entries.
10887 Next_Item : Node_Id;
10890 Item := First_Rep_Item (Full);
10892 -- If no existing rep items on full type, we can just link directly
10893 -- to the list of items on the private type.
10896 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
10898 -- Otherwise, search to the end of items currently linked to the full
10899 -- subtype and append the private items to the end. However, if Priv
10900 -- and Full already have the same list of rep items, then the append
10901 -- is not done, as that would create a circularity.
10903 elsif Item /= First_Rep_Item (Priv) then
10907 Next_Item := Next_Rep_Item (Item);
10908 exit when No (Next_Item);
10911 -- If the private view has aspect specifications, the full view
10912 -- inherits them. Since these aspects may already have been
10913 -- attached to the full view during derivation, do not append
10914 -- them if already present.
10916 if Item = First_Rep_Item (Priv) then
10922 -- And link the private type items at the end of the chain
10925 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
10930 -- Make sure Has_Predicates is set on full type if it is set on the
10931 -- private type. Note that it may already be set on the full type and
10932 -- if so, we don't want to unset it.
10934 if Has_Predicates (Priv) then
10935 Set_Has_Predicates (Full);
10937 end Complete_Private_Subtype;
10939 ----------------------------
10940 -- Constant_Redeclaration --
10941 ----------------------------
10943 procedure Constant_Redeclaration
10948 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
10949 Obj_Def : constant Node_Id := Object_Definition (N);
10952 procedure Check_Possible_Deferred_Completion
10953 (Prev_Id : Entity_Id;
10954 Prev_Obj_Def : Node_Id;
10955 Curr_Obj_Def : Node_Id);
10956 -- Determine whether the two object definitions describe the partial
10957 -- and the full view of a constrained deferred constant. Generate
10958 -- a subtype for the full view and verify that it statically matches
10959 -- the subtype of the partial view.
10961 procedure Check_Recursive_Declaration (Typ : Entity_Id);
10962 -- If deferred constant is an access type initialized with an allocator,
10963 -- check whether there is an illegal recursion in the definition,
10964 -- through a default value of some record subcomponent. This is normally
10965 -- detected when generating init procs, but requires this additional
10966 -- mechanism when expansion is disabled.
10968 ----------------------------------------
10969 -- Check_Possible_Deferred_Completion --
10970 ----------------------------------------
10972 procedure Check_Possible_Deferred_Completion
10973 (Prev_Id : Entity_Id;
10974 Prev_Obj_Def : Node_Id;
10975 Curr_Obj_Def : Node_Id)
10978 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
10979 and then Present (Constraint (Prev_Obj_Def))
10980 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
10981 and then Present (Constraint (Curr_Obj_Def))
10984 Loc : constant Source_Ptr := Sloc (N);
10985 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
10986 Decl : constant Node_Id :=
10987 Make_Subtype_Declaration (Loc,
10988 Defining_Identifier => Def_Id,
10989 Subtype_Indication =>
10990 Relocate_Node (Curr_Obj_Def));
10993 Insert_Before_And_Analyze (N, Decl);
10994 Set_Etype (Id, Def_Id);
10996 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
10997 Error_Msg_Sloc := Sloc (Prev_Id);
10998 Error_Msg_N ("subtype does not statically match deferred " &
10999 "declaration#", N);
11003 end Check_Possible_Deferred_Completion;
11005 ---------------------------------
11006 -- Check_Recursive_Declaration --
11007 ---------------------------------
11009 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
11013 if Is_Record_Type (Typ) then
11014 Comp := First_Component (Typ);
11015 while Present (Comp) loop
11016 if Comes_From_Source (Comp) then
11017 if Present (Expression (Parent (Comp)))
11018 and then Is_Entity_Name (Expression (Parent (Comp)))
11019 and then Entity (Expression (Parent (Comp))) = Prev
11021 Error_Msg_Sloc := Sloc (Parent (Comp));
11023 ("illegal circularity with declaration for&#",
11027 elsif Is_Record_Type (Etype (Comp)) then
11028 Check_Recursive_Declaration (Etype (Comp));
11032 Next_Component (Comp);
11035 end Check_Recursive_Declaration;
11037 -- Start of processing for Constant_Redeclaration
11040 if Nkind (Parent (Prev)) = N_Object_Declaration then
11041 if Nkind (Object_Definition
11042 (Parent (Prev))) = N_Subtype_Indication
11044 -- Find type of new declaration. The constraints of the two
11045 -- views must match statically, but there is no point in
11046 -- creating an itype for the full view.
11048 if Nkind (Obj_Def) = N_Subtype_Indication then
11049 Find_Type (Subtype_Mark (Obj_Def));
11050 New_T := Entity (Subtype_Mark (Obj_Def));
11053 Find_Type (Obj_Def);
11054 New_T := Entity (Obj_Def);
11060 -- The full view may impose a constraint, even if the partial
11061 -- view does not, so construct the subtype.
11063 New_T := Find_Type_Of_Object (Obj_Def, N);
11068 -- Current declaration is illegal, diagnosed below in Enter_Name
11074 -- If previous full declaration or a renaming declaration exists, or if
11075 -- a homograph is present, let Enter_Name handle it, either with an
11076 -- error or with the removal of an overridden implicit subprogram.
11077 -- The previous one is a full declaration if it has an expression
11078 -- (which in the case of an aggregate is indicated by the Init flag).
11080 if Ekind (Prev) /= E_Constant
11081 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
11082 or else Present (Expression (Parent (Prev)))
11083 or else Has_Init_Expression (Parent (Prev))
11084 or else Present (Full_View (Prev))
11088 -- Verify that types of both declarations match, or else that both types
11089 -- are anonymous access types whose designated subtypes statically match
11090 -- (as allowed in Ada 2005 by AI-385).
11092 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
11094 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
11095 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
11096 or else Is_Access_Constant (Etype (New_T)) /=
11097 Is_Access_Constant (Etype (Prev))
11098 or else Can_Never_Be_Null (Etype (New_T)) /=
11099 Can_Never_Be_Null (Etype (Prev))
11100 or else Null_Exclusion_Present (Parent (Prev)) /=
11101 Null_Exclusion_Present (Parent (Id))
11102 or else not Subtypes_Statically_Match
11103 (Designated_Type (Etype (Prev)),
11104 Designated_Type (Etype (New_T))))
11106 Error_Msg_Sloc := Sloc (Prev);
11107 Error_Msg_N ("type does not match declaration#", N);
11108 Set_Full_View (Prev, Id);
11109 Set_Etype (Id, Any_Type);
11112 Null_Exclusion_Present (Parent (Prev))
11113 and then not Null_Exclusion_Present (N)
11115 Error_Msg_Sloc := Sloc (Prev);
11116 Error_Msg_N ("null-exclusion does not match declaration#", N);
11117 Set_Full_View (Prev, Id);
11118 Set_Etype (Id, Any_Type);
11120 -- If so, process the full constant declaration
11123 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
11124 -- the deferred declaration is constrained, then the subtype defined
11125 -- by the subtype_indication in the full declaration shall match it
11128 Check_Possible_Deferred_Completion
11130 Prev_Obj_Def => Object_Definition (Parent (Prev)),
11131 Curr_Obj_Def => Obj_Def);
11133 Set_Full_View (Prev, Id);
11134 Set_Is_Public (Id, Is_Public (Prev));
11135 Set_Is_Internal (Id);
11136 Append_Entity (Id, Current_Scope);
11138 -- Check ALIASED present if present before (RM 7.4(7))
11140 if Is_Aliased (Prev)
11141 and then not Aliased_Present (N)
11143 Error_Msg_Sloc := Sloc (Prev);
11144 Error_Msg_N ("ALIASED required (see declaration#)", N);
11147 -- Check that placement is in private part and that the incomplete
11148 -- declaration appeared in the visible part.
11150 if Ekind (Current_Scope) = E_Package
11151 and then not In_Private_Part (Current_Scope)
11153 Error_Msg_Sloc := Sloc (Prev);
11155 ("full constant for declaration#"
11156 & " must be in private part", N);
11158 elsif Ekind (Current_Scope) = E_Package
11160 List_Containing (Parent (Prev)) /=
11161 Visible_Declarations (Package_Specification (Current_Scope))
11164 ("deferred constant must be declared in visible part",
11168 if Is_Access_Type (T)
11169 and then Nkind (Expression (N)) = N_Allocator
11171 Check_Recursive_Declaration (Designated_Type (T));
11174 -- A deferred constant is a visible entity. If type has invariants,
11175 -- verify that the initial value satisfies them.
11177 if Has_Invariants (T) and then Present (Invariant_Procedure (T)) then
11179 Make_Invariant_Call (New_Occurrence_Of (Prev, Sloc (N))));
11182 end Constant_Redeclaration;
11184 ----------------------
11185 -- Constrain_Access --
11186 ----------------------
11188 procedure Constrain_Access
11189 (Def_Id : in out Entity_Id;
11191 Related_Nod : Node_Id)
11193 T : constant Entity_Id := Entity (Subtype_Mark (S));
11194 Desig_Type : constant Entity_Id := Designated_Type (T);
11195 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
11196 Constraint_OK : Boolean := True;
11198 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean;
11199 -- Simple predicate to test for defaulted discriminants
11200 -- Shouldn't this be in sem_util???
11202 ---------------------------------
11203 -- Has_Defaulted_Discriminants --
11204 ---------------------------------
11206 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean is
11208 return Has_Discriminants (Typ)
11209 and then Present (First_Discriminant (Typ))
11211 (Discriminant_Default_Value (First_Discriminant (Typ)));
11212 end Has_Defaulted_Discriminants;
11214 -- Start of processing for Constrain_Access
11217 if Is_Array_Type (Desig_Type) then
11218 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
11220 elsif (Is_Record_Type (Desig_Type)
11221 or else Is_Incomplete_Or_Private_Type (Desig_Type))
11222 and then not Is_Constrained (Desig_Type)
11224 -- ??? The following code is a temporary bypass to ignore a
11225 -- discriminant constraint on access type if it is constraining
11226 -- the current record. Avoid creating the implicit subtype of the
11227 -- record we are currently compiling since right now, we cannot
11228 -- handle these. For now, just return the access type itself.
11230 if Desig_Type = Current_Scope
11231 and then No (Def_Id)
11233 Set_Ekind (Desig_Subtype, E_Record_Subtype);
11234 Def_Id := Entity (Subtype_Mark (S));
11236 -- This call added to ensure that the constraint is analyzed
11237 -- (needed for a B test). Note that we still return early from
11238 -- this procedure to avoid recursive processing. ???
11240 Constrain_Discriminated_Type
11241 (Desig_Subtype, S, Related_Nod, For_Access => True);
11245 -- Enforce rule that the constraint is illegal if there is an
11246 -- unconstrained view of the designated type. This means that the
11247 -- partial view (either a private type declaration or a derivation
11248 -- from a private type) has no discriminants. (Defect Report
11249 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
11251 -- Rule updated for Ada 2005: The private type is said to have
11252 -- a constrained partial view, given that objects of the type
11253 -- can be declared. Furthermore, the rule applies to all access
11254 -- types, unlike the rule concerning default discriminants (see
11257 if (Ekind (T) = E_General_Access_Type
11258 or else Ada_Version >= Ada_2005)
11259 and then Has_Private_Declaration (Desig_Type)
11260 and then In_Open_Scopes (Scope (Desig_Type))
11261 and then Has_Discriminants (Desig_Type)
11264 Pack : constant Node_Id :=
11265 Unit_Declaration_Node (Scope (Desig_Type));
11270 if Nkind (Pack) = N_Package_Declaration then
11271 Decls := Visible_Declarations (Specification (Pack));
11272 Decl := First (Decls);
11273 while Present (Decl) loop
11274 if (Nkind (Decl) = N_Private_Type_Declaration
11276 Chars (Defining_Identifier (Decl)) =
11277 Chars (Desig_Type))
11280 (Nkind (Decl) = N_Full_Type_Declaration
11282 Chars (Defining_Identifier (Decl)) =
11284 and then Is_Derived_Type (Desig_Type)
11286 Has_Private_Declaration (Etype (Desig_Type)))
11288 if No (Discriminant_Specifications (Decl)) then
11290 ("cannot constrain access type if designated " &
11291 "type has constrained partial view", S);
11303 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
11304 For_Access => True);
11306 elsif (Is_Task_Type (Desig_Type)
11307 or else Is_Protected_Type (Desig_Type))
11308 and then not Is_Constrained (Desig_Type)
11310 Constrain_Concurrent
11311 (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
11314 Error_Msg_N ("invalid constraint on access type", S);
11315 Desig_Subtype := Desig_Type; -- Ignore invalid constraint.
11316 Constraint_OK := False;
11319 if No (Def_Id) then
11320 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
11322 Set_Ekind (Def_Id, E_Access_Subtype);
11325 if Constraint_OK then
11326 Set_Etype (Def_Id, Base_Type (T));
11328 if Is_Private_Type (Desig_Type) then
11329 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
11332 Set_Etype (Def_Id, Any_Type);
11335 Set_Size_Info (Def_Id, T);
11336 Set_Is_Constrained (Def_Id, Constraint_OK);
11337 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
11338 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
11339 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
11341 Conditional_Delay (Def_Id, T);
11343 -- AI-363 : Subtypes of general access types whose designated types have
11344 -- default discriminants are disallowed. In instances, the rule has to
11345 -- be checked against the actual, of which T is the subtype. In a
11346 -- generic body, the rule is checked assuming that the actual type has
11347 -- defaulted discriminants.
11349 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
11350 if Ekind (Base_Type (T)) = E_General_Access_Type
11351 and then Has_Defaulted_Discriminants (Desig_Type)
11353 if Ada_Version < Ada_2005 then
11355 ("access subtype of general access type would not " &
11356 "be allowed in Ada 2005?y?", S);
11359 ("access subtype of general access type not allowed", S);
11362 Error_Msg_N ("\discriminants have defaults", S);
11364 elsif Is_Access_Type (T)
11365 and then Is_Generic_Type (Desig_Type)
11366 and then Has_Discriminants (Desig_Type)
11367 and then In_Package_Body (Current_Scope)
11369 if Ada_Version < Ada_2005 then
11371 ("access subtype would not be allowed in generic body " &
11372 "in Ada 2005?y?", S);
11375 ("access subtype not allowed in generic body", S);
11379 ("\designated type is a discriminated formal", S);
11382 end Constrain_Access;
11384 ---------------------
11385 -- Constrain_Array --
11386 ---------------------
11388 procedure Constrain_Array
11389 (Def_Id : in out Entity_Id;
11391 Related_Nod : Node_Id;
11392 Related_Id : Entity_Id;
11393 Suffix : Character)
11395 C : constant Node_Id := Constraint (SI);
11396 Number_Of_Constraints : Nat := 0;
11399 Constraint_OK : Boolean := True;
11402 T := Entity (Subtype_Mark (SI));
11404 if Is_Access_Type (T) then
11405 T := Designated_Type (T);
11408 -- If an index constraint follows a subtype mark in a subtype indication
11409 -- then the type or subtype denoted by the subtype mark must not already
11410 -- impose an index constraint. The subtype mark must denote either an
11411 -- unconstrained array type or an access type whose designated type
11412 -- is such an array type... (RM 3.6.1)
11414 if Is_Constrained (T) then
11415 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
11416 Constraint_OK := False;
11419 S := First (Constraints (C));
11420 while Present (S) loop
11421 Number_Of_Constraints := Number_Of_Constraints + 1;
11425 -- In either case, the index constraint must provide a discrete
11426 -- range for each index of the array type and the type of each
11427 -- discrete range must be the same as that of the corresponding
11428 -- index. (RM 3.6.1)
11430 if Number_Of_Constraints /= Number_Dimensions (T) then
11431 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
11432 Constraint_OK := False;
11435 S := First (Constraints (C));
11436 Index := First_Index (T);
11439 -- Apply constraints to each index type
11441 for J in 1 .. Number_Of_Constraints loop
11442 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
11450 if No (Def_Id) then
11452 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
11453 Set_Parent (Def_Id, Related_Nod);
11456 Set_Ekind (Def_Id, E_Array_Subtype);
11459 Set_Size_Info (Def_Id, (T));
11460 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11461 Set_Etype (Def_Id, Base_Type (T));
11463 if Constraint_OK then
11464 Set_First_Index (Def_Id, First (Constraints (C)));
11466 Set_First_Index (Def_Id, First_Index (T));
11469 Set_Is_Constrained (Def_Id, True);
11470 Set_Is_Aliased (Def_Id, Is_Aliased (T));
11471 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
11473 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
11474 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
11476 -- A subtype does not inherit the packed_array_type of is parent. We
11477 -- need to initialize the attribute because if Def_Id is previously
11478 -- analyzed through a limited_with clause, it will have the attributes
11479 -- of an incomplete type, one of which is an Elist that overlaps the
11480 -- Packed_Array_Type field.
11482 Set_Packed_Array_Type (Def_Id, Empty);
11484 -- Build a freeze node if parent still needs one. Also make sure that
11485 -- the Depends_On_Private status is set because the subtype will need
11486 -- reprocessing at the time the base type does, and also we must set a
11487 -- conditional delay.
11489 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
11490 Conditional_Delay (Def_Id, T);
11491 end Constrain_Array;
11493 ------------------------------
11494 -- Constrain_Component_Type --
11495 ------------------------------
11497 function Constrain_Component_Type
11499 Constrained_Typ : Entity_Id;
11500 Related_Node : Node_Id;
11502 Constraints : Elist_Id) return Entity_Id
11504 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
11505 Compon_Type : constant Entity_Id := Etype (Comp);
11506 Array_Comp : Node_Id;
11508 function Build_Constrained_Array_Type
11509 (Old_Type : Entity_Id) return Entity_Id;
11510 -- If Old_Type is an array type, one of whose indexes is constrained
11511 -- by a discriminant, build an Itype whose constraint replaces the
11512 -- discriminant with its value in the constraint.
11514 function Build_Constrained_Discriminated_Type
11515 (Old_Type : Entity_Id) return Entity_Id;
11516 -- Ditto for record components
11518 function Build_Constrained_Access_Type
11519 (Old_Type : Entity_Id) return Entity_Id;
11520 -- Ditto for access types. Makes use of previous two functions, to
11521 -- constrain designated type.
11523 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
11524 -- T is an array or discriminated type, C is a list of constraints
11525 -- that apply to T. This routine builds the constrained subtype.
11527 function Is_Discriminant (Expr : Node_Id) return Boolean;
11528 -- Returns True if Expr is a discriminant
11530 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
11531 -- Find the value of discriminant Discrim in Constraint
11533 -----------------------------------
11534 -- Build_Constrained_Access_Type --
11535 -----------------------------------
11537 function Build_Constrained_Access_Type
11538 (Old_Type : Entity_Id) return Entity_Id
11540 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
11542 Desig_Subtype : Entity_Id;
11546 -- if the original access type was not embedded in the enclosing
11547 -- type definition, there is no need to produce a new access
11548 -- subtype. In fact every access type with an explicit constraint
11549 -- generates an itype whose scope is the enclosing record.
11551 if not Is_Type (Scope (Old_Type)) then
11554 elsif Is_Array_Type (Desig_Type) then
11555 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
11557 elsif Has_Discriminants (Desig_Type) then
11559 -- This may be an access type to an enclosing record type for
11560 -- which we are constructing the constrained components. Return
11561 -- the enclosing record subtype. This is not always correct,
11562 -- but avoids infinite recursion. ???
11564 Desig_Subtype := Any_Type;
11566 for J in reverse 0 .. Scope_Stack.Last loop
11567 Scop := Scope_Stack.Table (J).Entity;
11570 and then Base_Type (Scop) = Base_Type (Desig_Type)
11572 Desig_Subtype := Scop;
11575 exit when not Is_Type (Scop);
11578 if Desig_Subtype = Any_Type then
11580 Build_Constrained_Discriminated_Type (Desig_Type);
11587 if Desig_Subtype /= Desig_Type then
11589 -- The Related_Node better be here or else we won't be able
11590 -- to attach new itypes to a node in the tree.
11592 pragma Assert (Present (Related_Node));
11594 Itype := Create_Itype (E_Access_Subtype, Related_Node);
11596 Set_Etype (Itype, Base_Type (Old_Type));
11597 Set_Size_Info (Itype, (Old_Type));
11598 Set_Directly_Designated_Type (Itype, Desig_Subtype);
11599 Set_Depends_On_Private (Itype, Has_Private_Component
11601 Set_Is_Access_Constant (Itype, Is_Access_Constant
11604 -- The new itype needs freezing when it depends on a not frozen
11605 -- type and the enclosing subtype needs freezing.
11607 if Has_Delayed_Freeze (Constrained_Typ)
11608 and then not Is_Frozen (Constrained_Typ)
11610 Conditional_Delay (Itype, Base_Type (Old_Type));
11618 end Build_Constrained_Access_Type;
11620 ----------------------------------
11621 -- Build_Constrained_Array_Type --
11622 ----------------------------------
11624 function Build_Constrained_Array_Type
11625 (Old_Type : Entity_Id) return Entity_Id
11629 Old_Index : Node_Id;
11630 Range_Node : Node_Id;
11631 Constr_List : List_Id;
11633 Need_To_Create_Itype : Boolean := False;
11636 Old_Index := First_Index (Old_Type);
11637 while Present (Old_Index) loop
11638 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
11640 if Is_Discriminant (Lo_Expr)
11641 or else Is_Discriminant (Hi_Expr)
11643 Need_To_Create_Itype := True;
11646 Next_Index (Old_Index);
11649 if Need_To_Create_Itype then
11650 Constr_List := New_List;
11652 Old_Index := First_Index (Old_Type);
11653 while Present (Old_Index) loop
11654 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
11656 if Is_Discriminant (Lo_Expr) then
11657 Lo_Expr := Get_Discr_Value (Lo_Expr);
11660 if Is_Discriminant (Hi_Expr) then
11661 Hi_Expr := Get_Discr_Value (Hi_Expr);
11666 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
11668 Append (Range_Node, To => Constr_List);
11670 Next_Index (Old_Index);
11673 return Build_Subtype (Old_Type, Constr_List);
11678 end Build_Constrained_Array_Type;
11680 ------------------------------------------
11681 -- Build_Constrained_Discriminated_Type --
11682 ------------------------------------------
11684 function Build_Constrained_Discriminated_Type
11685 (Old_Type : Entity_Id) return Entity_Id
11688 Constr_List : List_Id;
11689 Old_Constraint : Elmt_Id;
11691 Need_To_Create_Itype : Boolean := False;
11694 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
11695 while Present (Old_Constraint) loop
11696 Expr := Node (Old_Constraint);
11698 if Is_Discriminant (Expr) then
11699 Need_To_Create_Itype := True;
11702 Next_Elmt (Old_Constraint);
11705 if Need_To_Create_Itype then
11706 Constr_List := New_List;
11708 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
11709 while Present (Old_Constraint) loop
11710 Expr := Node (Old_Constraint);
11712 if Is_Discriminant (Expr) then
11713 Expr := Get_Discr_Value (Expr);
11716 Append (New_Copy_Tree (Expr), To => Constr_List);
11718 Next_Elmt (Old_Constraint);
11721 return Build_Subtype (Old_Type, Constr_List);
11726 end Build_Constrained_Discriminated_Type;
11728 -------------------
11729 -- Build_Subtype --
11730 -------------------
11732 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
11734 Subtyp_Decl : Node_Id;
11735 Def_Id : Entity_Id;
11736 Btyp : Entity_Id := Base_Type (T);
11739 -- The Related_Node better be here or else we won't be able to
11740 -- attach new itypes to a node in the tree.
11742 pragma Assert (Present (Related_Node));
11744 -- If the view of the component's type is incomplete or private
11745 -- with unknown discriminants, then the constraint must be applied
11746 -- to the full type.
11748 if Has_Unknown_Discriminants (Btyp)
11749 and then Present (Underlying_Type (Btyp))
11751 Btyp := Underlying_Type (Btyp);
11755 Make_Subtype_Indication (Loc,
11756 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
11757 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
11759 Def_Id := Create_Itype (Ekind (T), Related_Node);
11762 Make_Subtype_Declaration (Loc,
11763 Defining_Identifier => Def_Id,
11764 Subtype_Indication => Indic);
11766 Set_Parent (Subtyp_Decl, Parent (Related_Node));
11768 -- Itypes must be analyzed with checks off (see package Itypes)
11770 Analyze (Subtyp_Decl, Suppress => All_Checks);
11775 ---------------------
11776 -- Get_Discr_Value --
11777 ---------------------
11779 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
11784 -- The discriminant may be declared for the type, in which case we
11785 -- find it by iterating over the list of discriminants. If the
11786 -- discriminant is inherited from a parent type, it appears as the
11787 -- corresponding discriminant of the current type. This will be the
11788 -- case when constraining an inherited component whose constraint is
11789 -- given by a discriminant of the parent.
11791 D := First_Discriminant (Typ);
11792 E := First_Elmt (Constraints);
11794 while Present (D) loop
11795 if D = Entity (Discrim)
11796 or else D = CR_Discriminant (Entity (Discrim))
11797 or else Corresponding_Discriminant (D) = Entity (Discrim)
11802 Next_Discriminant (D);
11806 -- The Corresponding_Discriminant mechanism is incomplete, because
11807 -- the correspondence between new and old discriminants is not one
11808 -- to one: one new discriminant can constrain several old ones. In
11809 -- that case, scan sequentially the stored_constraint, the list of
11810 -- discriminants of the parents, and the constraints.
11812 -- Previous code checked for the present of the Stored_Constraint
11813 -- list for the derived type, but did not use it at all. Should it
11814 -- be present when the component is a discriminated task type?
11816 if Is_Derived_Type (Typ)
11817 and then Scope (Entity (Discrim)) = Etype (Typ)
11819 D := First_Discriminant (Etype (Typ));
11820 E := First_Elmt (Constraints);
11821 while Present (D) loop
11822 if D = Entity (Discrim) then
11826 Next_Discriminant (D);
11831 -- Something is wrong if we did not find the value
11833 raise Program_Error;
11834 end Get_Discr_Value;
11836 ---------------------
11837 -- Is_Discriminant --
11838 ---------------------
11840 function Is_Discriminant (Expr : Node_Id) return Boolean is
11841 Discrim_Scope : Entity_Id;
11844 if Denotes_Discriminant (Expr) then
11845 Discrim_Scope := Scope (Entity (Expr));
11847 -- Either we have a reference to one of Typ's discriminants,
11849 pragma Assert (Discrim_Scope = Typ
11851 -- or to the discriminants of the parent type, in the case
11852 -- of a derivation of a tagged type with variants.
11854 or else Discrim_Scope = Etype (Typ)
11855 or else Full_View (Discrim_Scope) = Etype (Typ)
11857 -- or same as above for the case where the discriminants
11858 -- were declared in Typ's private view.
11860 or else (Is_Private_Type (Discrim_Scope)
11861 and then Chars (Discrim_Scope) = Chars (Typ))
11863 -- or else we are deriving from the full view and the
11864 -- discriminant is declared in the private entity.
11866 or else (Is_Private_Type (Typ)
11867 and then Chars (Discrim_Scope) = Chars (Typ))
11869 -- Or we are constrained the corresponding record of a
11870 -- synchronized type that completes a private declaration.
11872 or else (Is_Concurrent_Record_Type (Typ)
11874 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
11876 -- or we have a class-wide type, in which case make sure the
11877 -- discriminant found belongs to the root type.
11879 or else (Is_Class_Wide_Type (Typ)
11880 and then Etype (Typ) = Discrim_Scope));
11885 -- In all other cases we have something wrong
11888 end Is_Discriminant;
11890 -- Start of processing for Constrain_Component_Type
11893 if Nkind (Parent (Comp)) = N_Component_Declaration
11894 and then Comes_From_Source (Parent (Comp))
11895 and then Comes_From_Source
11896 (Subtype_Indication (Component_Definition (Parent (Comp))))
11899 (Subtype_Indication (Component_Definition (Parent (Comp))))
11901 return Compon_Type;
11903 elsif Is_Array_Type (Compon_Type) then
11904 Array_Comp := Build_Constrained_Array_Type (Compon_Type);
11906 -- If the component of the parent is packed, and the record type is
11907 -- already frozen, as is the case for an itype, the component type
11908 -- itself will not be frozen, and the packed array type for it must
11909 -- be constructed explicitly. Since the creation of packed types is
11910 -- an expansion activity, we only do this if expansion is active.
11913 and then Is_Packed (Compon_Type)
11914 and then Is_Frozen (Current_Scope)
11916 Create_Packed_Array_Type (Array_Comp);
11921 elsif Has_Discriminants (Compon_Type) then
11922 return Build_Constrained_Discriminated_Type (Compon_Type);
11924 elsif Is_Access_Type (Compon_Type) then
11925 return Build_Constrained_Access_Type (Compon_Type);
11928 return Compon_Type;
11930 end Constrain_Component_Type;
11932 --------------------------
11933 -- Constrain_Concurrent --
11934 --------------------------
11936 -- For concurrent types, the associated record value type carries the same
11937 -- discriminants, so when we constrain a concurrent type, we must constrain
11938 -- the corresponding record type as well.
11940 procedure Constrain_Concurrent
11941 (Def_Id : in out Entity_Id;
11943 Related_Nod : Node_Id;
11944 Related_Id : Entity_Id;
11945 Suffix : Character)
11947 -- Retrieve Base_Type to ensure getting to the concurrent type in the
11948 -- case of a private subtype (needed when only doing semantic analysis).
11950 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
11954 if Is_Access_Type (T_Ent) then
11955 T_Ent := Designated_Type (T_Ent);
11958 T_Val := Corresponding_Record_Type (T_Ent);
11960 if Present (T_Val) then
11962 if No (Def_Id) then
11963 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
11966 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
11968 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
11969 Set_Corresponding_Record_Type (Def_Id,
11970 Constrain_Corresponding_Record
11971 (Def_Id, T_Val, Related_Nod, Related_Id));
11974 -- If there is no associated record, expansion is disabled and this
11975 -- is a generic context. Create a subtype in any case, so that
11976 -- semantic analysis can proceed.
11978 if No (Def_Id) then
11979 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
11982 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
11984 end Constrain_Concurrent;
11986 ------------------------------------
11987 -- Constrain_Corresponding_Record --
11988 ------------------------------------
11990 function Constrain_Corresponding_Record
11991 (Prot_Subt : Entity_Id;
11992 Corr_Rec : Entity_Id;
11993 Related_Nod : Node_Id;
11994 Related_Id : Entity_Id) return Entity_Id
11996 T_Sub : constant Entity_Id :=
11997 Create_Itype (E_Record_Subtype, Related_Nod, Related_Id, 'V');
12000 Set_Etype (T_Sub, Corr_Rec);
12001 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
12002 Set_Is_Constrained (T_Sub, True);
12003 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
12004 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
12006 -- As elsewhere, we do not want to create a freeze node for this itype
12007 -- if it is created for a constrained component of an enclosing record
12008 -- because references to outer discriminants will appear out of scope.
12010 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
12011 Conditional_Delay (T_Sub, Corr_Rec);
12013 Set_Is_Frozen (T_Sub);
12016 if Has_Discriminants (Prot_Subt) then -- False only if errors.
12017 Set_Discriminant_Constraint
12018 (T_Sub, Discriminant_Constraint (Prot_Subt));
12019 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
12020 Create_Constrained_Components
12021 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
12024 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
12027 end Constrain_Corresponding_Record;
12029 -----------------------
12030 -- Constrain_Decimal --
12031 -----------------------
12033 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
12034 T : constant Entity_Id := Entity (Subtype_Mark (S));
12035 C : constant Node_Id := Constraint (S);
12036 Loc : constant Source_Ptr := Sloc (C);
12037 Range_Expr : Node_Id;
12038 Digits_Expr : Node_Id;
12043 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
12045 if Nkind (C) = N_Range_Constraint then
12046 Range_Expr := Range_Expression (C);
12047 Digits_Val := Digits_Value (T);
12050 pragma Assert (Nkind (C) = N_Digits_Constraint);
12052 Check_SPARK_Restriction ("digits constraint is not allowed", S);
12054 Digits_Expr := Digits_Expression (C);
12055 Analyze_And_Resolve (Digits_Expr, Any_Integer);
12057 Check_Digits_Expression (Digits_Expr);
12058 Digits_Val := Expr_Value (Digits_Expr);
12060 if Digits_Val > Digits_Value (T) then
12062 ("digits expression is incompatible with subtype", C);
12063 Digits_Val := Digits_Value (T);
12066 if Present (Range_Constraint (C)) then
12067 Range_Expr := Range_Expression (Range_Constraint (C));
12069 Range_Expr := Empty;
12073 Set_Etype (Def_Id, Base_Type (T));
12074 Set_Size_Info (Def_Id, (T));
12075 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12076 Set_Delta_Value (Def_Id, Delta_Value (T));
12077 Set_Scale_Value (Def_Id, Scale_Value (T));
12078 Set_Small_Value (Def_Id, Small_Value (T));
12079 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
12080 Set_Digits_Value (Def_Id, Digits_Val);
12082 -- Manufacture range from given digits value if no range present
12084 if No (Range_Expr) then
12085 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
12089 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
12091 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
12094 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
12095 Set_Discrete_RM_Size (Def_Id);
12097 -- Unconditionally delay the freeze, since we cannot set size
12098 -- information in all cases correctly until the freeze point.
12100 Set_Has_Delayed_Freeze (Def_Id);
12101 end Constrain_Decimal;
12103 ----------------------------------
12104 -- Constrain_Discriminated_Type --
12105 ----------------------------------
12107 procedure Constrain_Discriminated_Type
12108 (Def_Id : Entity_Id;
12110 Related_Nod : Node_Id;
12111 For_Access : Boolean := False)
12113 E : constant Entity_Id := Entity (Subtype_Mark (S));
12116 Elist : Elist_Id := New_Elmt_List;
12118 procedure Fixup_Bad_Constraint;
12119 -- This is called after finding a bad constraint, and after having
12120 -- posted an appropriate error message. The mission is to leave the
12121 -- entity T in as reasonable state as possible.
12123 --------------------------
12124 -- Fixup_Bad_Constraint --
12125 --------------------------
12127 procedure Fixup_Bad_Constraint is
12129 -- Set a reasonable Ekind for the entity. For an incomplete type,
12130 -- we can't do much, but for other types, we can set the proper
12131 -- corresponding subtype kind.
12133 if Ekind (T) = E_Incomplete_Type then
12134 Set_Ekind (Def_Id, Ekind (T));
12136 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
12139 -- Set Etype to the known type, to reduce chances of cascaded errors
12141 Set_Etype (Def_Id, E);
12142 Set_Error_Posted (Def_Id);
12143 end Fixup_Bad_Constraint;
12145 -- Start of processing for Constrain_Discriminated_Type
12148 C := Constraint (S);
12150 -- A discriminant constraint is only allowed in a subtype indication,
12151 -- after a subtype mark. This subtype mark must denote either a type
12152 -- with discriminants, or an access type whose designated type is a
12153 -- type with discriminants. A discriminant constraint specifies the
12154 -- values of these discriminants (RM 3.7.2(5)).
12156 T := Base_Type (Entity (Subtype_Mark (S)));
12158 if Is_Access_Type (T) then
12159 T := Designated_Type (T);
12162 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
12163 -- Avoid generating an error for access-to-incomplete subtypes.
12165 if Ada_Version >= Ada_2005
12166 and then Ekind (T) = E_Incomplete_Type
12167 and then Nkind (Parent (S)) = N_Subtype_Declaration
12168 and then not Is_Itype (Def_Id)
12170 -- A little sanity check, emit an error message if the type
12171 -- has discriminants to begin with. Type T may be a regular
12172 -- incomplete type or imported via a limited with clause.
12174 if Has_Discriminants (T)
12175 or else (From_Limited_With (T)
12176 and then Present (Non_Limited_View (T))
12177 and then Nkind (Parent (Non_Limited_View (T))) =
12178 N_Full_Type_Declaration
12179 and then Present (Discriminant_Specifications
12180 (Parent (Non_Limited_View (T)))))
12183 ("(Ada 2005) incomplete subtype may not be constrained", C);
12185 Error_Msg_N ("invalid constraint: type has no discriminant", C);
12188 Fixup_Bad_Constraint;
12191 -- Check that the type has visible discriminants. The type may be
12192 -- a private type with unknown discriminants whose full view has
12193 -- discriminants which are invisible.
12195 elsif not Has_Discriminants (T)
12197 (Has_Unknown_Discriminants (T)
12198 and then Is_Private_Type (T))
12200 Error_Msg_N ("invalid constraint: type has no discriminant", C);
12201 Fixup_Bad_Constraint;
12204 elsif Is_Constrained (E)
12205 or else (Ekind (E) = E_Class_Wide_Subtype
12206 and then Present (Discriminant_Constraint (E)))
12208 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
12209 Fixup_Bad_Constraint;
12213 -- T may be an unconstrained subtype (e.g. a generic actual).
12214 -- Constraint applies to the base type.
12216 T := Base_Type (T);
12218 Elist := Build_Discriminant_Constraints (T, S);
12220 -- If the list returned was empty we had an error in building the
12221 -- discriminant constraint. We have also already signalled an error
12222 -- in the incomplete type case
12224 if Is_Empty_Elmt_List (Elist) then
12225 Fixup_Bad_Constraint;
12229 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
12230 end Constrain_Discriminated_Type;
12232 ---------------------------
12233 -- Constrain_Enumeration --
12234 ---------------------------
12236 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
12237 T : constant Entity_Id := Entity (Subtype_Mark (S));
12238 C : constant Node_Id := Constraint (S);
12241 Set_Ekind (Def_Id, E_Enumeration_Subtype);
12243 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
12245 Set_Etype (Def_Id, Base_Type (T));
12246 Set_Size_Info (Def_Id, (T));
12247 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12248 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
12250 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
12252 Set_Discrete_RM_Size (Def_Id);
12253 end Constrain_Enumeration;
12255 ----------------------
12256 -- Constrain_Float --
12257 ----------------------
12259 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
12260 T : constant Entity_Id := Entity (Subtype_Mark (S));
12266 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
12268 Set_Etype (Def_Id, Base_Type (T));
12269 Set_Size_Info (Def_Id, (T));
12270 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12272 -- Process the constraint
12274 C := Constraint (S);
12276 -- Digits constraint present
12278 if Nkind (C) = N_Digits_Constraint then
12280 Check_SPARK_Restriction ("digits constraint is not allowed", S);
12281 Check_Restriction (No_Obsolescent_Features, C);
12283 if Warn_On_Obsolescent_Feature then
12285 ("subtype digits constraint is an " &
12286 "obsolescent feature (RM J.3(8))?j?", C);
12289 D := Digits_Expression (C);
12290 Analyze_And_Resolve (D, Any_Integer);
12291 Check_Digits_Expression (D);
12292 Set_Digits_Value (Def_Id, Expr_Value (D));
12294 -- Check that digits value is in range. Obviously we can do this
12295 -- at compile time, but it is strictly a runtime check, and of
12296 -- course there is an ACVC test that checks this.
12298 if Digits_Value (Def_Id) > Digits_Value (T) then
12299 Error_Msg_Uint_1 := Digits_Value (T);
12300 Error_Msg_N ("??digits value is too large, maximum is ^", D);
12302 Make_Raise_Constraint_Error (Sloc (D),
12303 Reason => CE_Range_Check_Failed);
12304 Insert_Action (Declaration_Node (Def_Id), Rais);
12307 C := Range_Constraint (C);
12309 -- No digits constraint present
12312 Set_Digits_Value (Def_Id, Digits_Value (T));
12315 -- Range constraint present
12317 if Nkind (C) = N_Range_Constraint then
12318 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
12320 -- No range constraint present
12323 pragma Assert (No (C));
12324 Set_Scalar_Range (Def_Id, Scalar_Range (T));
12327 Set_Is_Constrained (Def_Id);
12328 end Constrain_Float;
12330 ---------------------
12331 -- Constrain_Index --
12332 ---------------------
12334 procedure Constrain_Index
12337 Related_Nod : Node_Id;
12338 Related_Id : Entity_Id;
12339 Suffix : Character;
12340 Suffix_Index : Nat)
12342 Def_Id : Entity_Id;
12343 R : Node_Id := Empty;
12344 T : constant Entity_Id := Etype (Index);
12347 if Nkind (S) = N_Range
12349 (Nkind (S) = N_Attribute_Reference
12350 and then Attribute_Name (S) = Name_Range)
12352 -- A Range attribute will be transformed into N_Range by Resolve
12358 Process_Range_Expr_In_Decl (R, T, Empty_List);
12360 if not Error_Posted (S)
12362 (Nkind (S) /= N_Range
12363 or else not Covers (T, (Etype (Low_Bound (S))))
12364 or else not Covers (T, (Etype (High_Bound (S)))))
12366 if Base_Type (T) /= Any_Type
12367 and then Etype (Low_Bound (S)) /= Any_Type
12368 and then Etype (High_Bound (S)) /= Any_Type
12370 Error_Msg_N ("range expected", S);
12374 elsif Nkind (S) = N_Subtype_Indication then
12376 -- The parser has verified that this is a discrete indication
12378 Resolve_Discrete_Subtype_Indication (S, T);
12379 R := Range_Expression (Constraint (S));
12381 -- Capture values of bounds and generate temporaries for them if
12382 -- needed, since checks may cause duplication of the expressions
12383 -- which must not be reevaluated.
12385 -- The forced evaluation removes side effects from expressions, which
12386 -- should occur also in GNATprove mode. Otherwise, we end up with
12387 -- unexpected insertions of actions at places where this is not
12388 -- supposed to occur, e.g. on default parameters of a call.
12390 if Expander_Active or GNATprove_Mode then
12391 Force_Evaluation (Low_Bound (R));
12392 Force_Evaluation (High_Bound (R));
12395 elsif Nkind (S) = N_Discriminant_Association then
12397 -- Syntactically valid in subtype indication
12399 Error_Msg_N ("invalid index constraint", S);
12400 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
12403 -- Subtype_Mark case, no anonymous subtypes to construct
12408 if Is_Entity_Name (S) then
12409 if not Is_Type (Entity (S)) then
12410 Error_Msg_N ("expect subtype mark for index constraint", S);
12412 elsif Base_Type (Entity (S)) /= Base_Type (T) then
12413 Wrong_Type (S, Base_Type (T));
12415 -- Check error of subtype with predicate in index constraint
12418 Bad_Predicated_Subtype_Use
12419 ("subtype& has predicate, not allowed in index constraint",
12426 Error_Msg_N ("invalid index constraint", S);
12427 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
12433 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
12435 Set_Etype (Def_Id, Base_Type (T));
12437 if Is_Modular_Integer_Type (T) then
12438 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
12440 elsif Is_Integer_Type (T) then
12441 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
12444 Set_Ekind (Def_Id, E_Enumeration_Subtype);
12445 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
12446 Set_First_Literal (Def_Id, First_Literal (T));
12449 Set_Size_Info (Def_Id, (T));
12450 Set_RM_Size (Def_Id, RM_Size (T));
12451 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12453 Set_Scalar_Range (Def_Id, R);
12455 Set_Etype (S, Def_Id);
12456 Set_Discrete_RM_Size (Def_Id);
12457 end Constrain_Index;
12459 -----------------------
12460 -- Constrain_Integer --
12461 -----------------------
12463 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
12464 T : constant Entity_Id := Entity (Subtype_Mark (S));
12465 C : constant Node_Id := Constraint (S);
12468 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
12470 if Is_Modular_Integer_Type (T) then
12471 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
12473 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
12476 Set_Etype (Def_Id, Base_Type (T));
12477 Set_Size_Info (Def_Id, (T));
12478 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12479 Set_Discrete_RM_Size (Def_Id);
12480 end Constrain_Integer;
12482 ------------------------------
12483 -- Constrain_Ordinary_Fixed --
12484 ------------------------------
12486 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
12487 T : constant Entity_Id := Entity (Subtype_Mark (S));
12493 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
12494 Set_Etype (Def_Id, Base_Type (T));
12495 Set_Size_Info (Def_Id, (T));
12496 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12497 Set_Small_Value (Def_Id, Small_Value (T));
12499 -- Process the constraint
12501 C := Constraint (S);
12503 -- Delta constraint present
12505 if Nkind (C) = N_Delta_Constraint then
12507 Check_SPARK_Restriction ("delta constraint is not allowed", S);
12508 Check_Restriction (No_Obsolescent_Features, C);
12510 if Warn_On_Obsolescent_Feature then
12512 ("subtype delta constraint is an " &
12513 "obsolescent feature (RM J.3(7))?j?");
12516 D := Delta_Expression (C);
12517 Analyze_And_Resolve (D, Any_Real);
12518 Check_Delta_Expression (D);
12519 Set_Delta_Value (Def_Id, Expr_Value_R (D));
12521 -- Check that delta value is in range. Obviously we can do this
12522 -- at compile time, but it is strictly a runtime check, and of
12523 -- course there is an ACVC test that checks this.
12525 if Delta_Value (Def_Id) < Delta_Value (T) then
12526 Error_Msg_N ("??delta value is too small", D);
12528 Make_Raise_Constraint_Error (Sloc (D),
12529 Reason => CE_Range_Check_Failed);
12530 Insert_Action (Declaration_Node (Def_Id), Rais);
12533 C := Range_Constraint (C);
12535 -- No delta constraint present
12538 Set_Delta_Value (Def_Id, Delta_Value (T));
12541 -- Range constraint present
12543 if Nkind (C) = N_Range_Constraint then
12544 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
12546 -- No range constraint present
12549 pragma Assert (No (C));
12550 Set_Scalar_Range (Def_Id, Scalar_Range (T));
12554 Set_Discrete_RM_Size (Def_Id);
12556 -- Unconditionally delay the freeze, since we cannot set size
12557 -- information in all cases correctly until the freeze point.
12559 Set_Has_Delayed_Freeze (Def_Id);
12560 end Constrain_Ordinary_Fixed;
12562 -----------------------
12563 -- Contain_Interface --
12564 -----------------------
12566 function Contain_Interface
12567 (Iface : Entity_Id;
12568 Ifaces : Elist_Id) return Boolean
12570 Iface_Elmt : Elmt_Id;
12573 if Present (Ifaces) then
12574 Iface_Elmt := First_Elmt (Ifaces);
12575 while Present (Iface_Elmt) loop
12576 if Node (Iface_Elmt) = Iface then
12580 Next_Elmt (Iface_Elmt);
12585 end Contain_Interface;
12587 ---------------------------
12588 -- Convert_Scalar_Bounds --
12589 ---------------------------
12591 procedure Convert_Scalar_Bounds
12593 Parent_Type : Entity_Id;
12594 Derived_Type : Entity_Id;
12597 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
12604 -- Defend against previous errors
12606 if No (Scalar_Range (Derived_Type)) then
12607 Check_Error_Detected;
12611 Lo := Build_Scalar_Bound
12612 (Type_Low_Bound (Derived_Type),
12613 Parent_Type, Implicit_Base);
12615 Hi := Build_Scalar_Bound
12616 (Type_High_Bound (Derived_Type),
12617 Parent_Type, Implicit_Base);
12624 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
12626 Set_Parent (Rng, N);
12627 Set_Scalar_Range (Derived_Type, Rng);
12629 -- Analyze the bounds
12631 Analyze_And_Resolve (Lo, Implicit_Base);
12632 Analyze_And_Resolve (Hi, Implicit_Base);
12634 -- Analyze the range itself, except that we do not analyze it if
12635 -- the bounds are real literals, and we have a fixed-point type.
12636 -- The reason for this is that we delay setting the bounds in this
12637 -- case till we know the final Small and Size values (see circuit
12638 -- in Freeze.Freeze_Fixed_Point_Type for further details).
12640 if Is_Fixed_Point_Type (Parent_Type)
12641 and then Nkind (Lo) = N_Real_Literal
12642 and then Nkind (Hi) = N_Real_Literal
12646 -- Here we do the analysis of the range
12648 -- Note: we do this manually, since if we do a normal Analyze and
12649 -- Resolve call, there are problems with the conversions used for
12650 -- the derived type range.
12653 Set_Etype (Rng, Implicit_Base);
12654 Set_Analyzed (Rng, True);
12656 end Convert_Scalar_Bounds;
12658 -------------------
12659 -- Copy_And_Swap --
12660 -------------------
12662 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
12664 -- Initialize new full declaration entity by copying the pertinent
12665 -- fields of the corresponding private declaration entity.
12667 -- We temporarily set Ekind to a value appropriate for a type to
12668 -- avoid assert failures in Einfo from checking for setting type
12669 -- attributes on something that is not a type. Ekind (Priv) is an
12670 -- appropriate choice, since it allowed the attributes to be set
12671 -- in the first place. This Ekind value will be modified later.
12673 Set_Ekind (Full, Ekind (Priv));
12675 -- Also set Etype temporarily to Any_Type, again, in the absence
12676 -- of errors, it will be properly reset, and if there are errors,
12677 -- then we want a value of Any_Type to remain.
12679 Set_Etype (Full, Any_Type);
12681 -- Now start copying attributes
12683 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
12685 if Has_Discriminants (Full) then
12686 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
12687 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
12690 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
12691 Set_Homonym (Full, Homonym (Priv));
12692 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
12693 Set_Is_Public (Full, Is_Public (Priv));
12694 Set_Is_Pure (Full, Is_Pure (Priv));
12695 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
12696 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
12697 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
12698 Set_Has_Pragma_Unreferenced_Objects
12699 (Full, Has_Pragma_Unreferenced_Objects
12702 Conditional_Delay (Full, Priv);
12704 if Is_Tagged_Type (Full) then
12705 Set_Direct_Primitive_Operations (Full,
12706 Direct_Primitive_Operations (Priv));
12708 if Is_Base_Type (Priv) then
12709 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
12713 Set_Is_Volatile (Full, Is_Volatile (Priv));
12714 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
12715 Set_Scope (Full, Scope (Priv));
12716 Set_Next_Entity (Full, Next_Entity (Priv));
12717 Set_First_Entity (Full, First_Entity (Priv));
12718 Set_Last_Entity (Full, Last_Entity (Priv));
12720 -- If access types have been recorded for later handling, keep them in
12721 -- the full view so that they get handled when the full view freeze
12722 -- node is expanded.
12724 if Present (Freeze_Node (Priv))
12725 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
12727 Ensure_Freeze_Node (Full);
12728 Set_Access_Types_To_Process
12729 (Freeze_Node (Full),
12730 Access_Types_To_Process (Freeze_Node (Priv)));
12733 -- Swap the two entities. Now Private is the full type entity and Full
12734 -- is the private one. They will be swapped back at the end of the
12735 -- private part. This swapping ensures that the entity that is visible
12736 -- in the private part is the full declaration.
12738 Exchange_Entities (Priv, Full);
12739 Append_Entity (Full, Scope (Full));
12742 -------------------------------------
12743 -- Copy_Array_Base_Type_Attributes --
12744 -------------------------------------
12746 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
12748 Set_Component_Alignment (T1, Component_Alignment (T2));
12749 Set_Component_Type (T1, Component_Type (T2));
12750 Set_Component_Size (T1, Component_Size (T2));
12751 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
12752 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
12753 Set_Has_Task (T1, Has_Task (T2));
12754 Set_Is_Packed (T1, Is_Packed (T2));
12755 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
12756 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
12757 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
12758 end Copy_Array_Base_Type_Attributes;
12760 -----------------------------------
12761 -- Copy_Array_Subtype_Attributes --
12762 -----------------------------------
12764 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
12766 Set_Size_Info (T1, T2);
12768 Set_First_Index (T1, First_Index (T2));
12769 Set_Is_Aliased (T1, Is_Aliased (T2));
12770 Set_Is_Volatile (T1, Is_Volatile (T2));
12771 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
12772 Set_Is_Constrained (T1, Is_Constrained (T2));
12773 Set_Depends_On_Private (T1, Has_Private_Component (T2));
12774 Set_First_Rep_Item (T1, First_Rep_Item (T2));
12775 Set_Convention (T1, Convention (T2));
12776 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
12777 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
12778 Set_Packed_Array_Type (T1, Packed_Array_Type (T2));
12779 end Copy_Array_Subtype_Attributes;
12781 -----------------------------------
12782 -- Create_Constrained_Components --
12783 -----------------------------------
12785 procedure Create_Constrained_Components
12787 Decl_Node : Node_Id;
12789 Constraints : Elist_Id)
12791 Loc : constant Source_Ptr := Sloc (Subt);
12792 Comp_List : constant Elist_Id := New_Elmt_List;
12793 Parent_Type : constant Entity_Id := Etype (Typ);
12794 Assoc_List : constant List_Id := New_List;
12795 Discr_Val : Elmt_Id;
12799 Is_Static : Boolean := True;
12801 procedure Collect_Fixed_Components (Typ : Entity_Id);
12802 -- Collect parent type components that do not appear in a variant part
12804 procedure Create_All_Components;
12805 -- Iterate over Comp_List to create the components of the subtype
12807 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
12808 -- Creates a new component from Old_Compon, copying all the fields from
12809 -- it, including its Etype, inserts the new component in the Subt entity
12810 -- chain and returns the new component.
12812 function Is_Variant_Record (T : Entity_Id) return Boolean;
12813 -- If true, and discriminants are static, collect only components from
12814 -- variants selected by discriminant values.
12816 ------------------------------
12817 -- Collect_Fixed_Components --
12818 ------------------------------
12820 procedure Collect_Fixed_Components (Typ : Entity_Id) is
12822 -- Build association list for discriminants, and find components of the
12823 -- variant part selected by the values of the discriminants.
12825 Old_C := First_Discriminant (Typ);
12826 Discr_Val := First_Elmt (Constraints);
12827 while Present (Old_C) loop
12828 Append_To (Assoc_List,
12829 Make_Component_Association (Loc,
12830 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
12831 Expression => New_Copy (Node (Discr_Val))));
12833 Next_Elmt (Discr_Val);
12834 Next_Discriminant (Old_C);
12837 -- The tag and the possible parent component are unconditionally in
12840 if Is_Tagged_Type (Typ)
12841 or else Has_Controlled_Component (Typ)
12843 Old_C := First_Component (Typ);
12844 while Present (Old_C) loop
12845 if Nam_In (Chars (Old_C), Name_uTag, Name_uParent) then
12846 Append_Elmt (Old_C, Comp_List);
12849 Next_Component (Old_C);
12852 end Collect_Fixed_Components;
12854 ---------------------------
12855 -- Create_All_Components --
12856 ---------------------------
12858 procedure Create_All_Components is
12862 Comp := First_Elmt (Comp_List);
12863 while Present (Comp) loop
12864 Old_C := Node (Comp);
12865 New_C := Create_Component (Old_C);
12869 Constrain_Component_Type
12870 (Old_C, Subt, Decl_Node, Typ, Constraints));
12871 Set_Is_Public (New_C, Is_Public (Subt));
12875 end Create_All_Components;
12877 ----------------------
12878 -- Create_Component --
12879 ----------------------
12881 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
12882 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
12885 if Ekind (Old_Compon) = E_Discriminant
12886 and then Is_Completely_Hidden (Old_Compon)
12888 -- This is a shadow discriminant created for a discriminant of
12889 -- the parent type, which needs to be present in the subtype.
12890 -- Give the shadow discriminant an internal name that cannot
12891 -- conflict with that of visible components.
12893 Set_Chars (New_Compon, New_Internal_Name ('C'));
12896 -- Set the parent so we have a proper link for freezing etc. This is
12897 -- not a real parent pointer, since of course our parent does not own
12898 -- up to us and reference us, we are an illegitimate child of the
12899 -- original parent.
12901 Set_Parent (New_Compon, Parent (Old_Compon));
12903 -- If the old component's Esize was already determined and is a
12904 -- static value, then the new component simply inherits it. Otherwise
12905 -- the old component's size may require run-time determination, but
12906 -- the new component's size still might be statically determinable
12907 -- (if, for example it has a static constraint). In that case we want
12908 -- Layout_Type to recompute the component's size, so we reset its
12909 -- size and positional fields.
12911 if Frontend_Layout_On_Target
12912 and then not Known_Static_Esize (Old_Compon)
12914 Set_Esize (New_Compon, Uint_0);
12915 Init_Normalized_First_Bit (New_Compon);
12916 Init_Normalized_Position (New_Compon);
12917 Init_Normalized_Position_Max (New_Compon);
12920 -- We do not want this node marked as Comes_From_Source, since
12921 -- otherwise it would get first class status and a separate cross-
12922 -- reference line would be generated. Illegitimate children do not
12923 -- rate such recognition.
12925 Set_Comes_From_Source (New_Compon, False);
12927 -- But it is a real entity, and a birth certificate must be properly
12928 -- registered by entering it into the entity list.
12930 Enter_Name (New_Compon);
12933 end Create_Component;
12935 -----------------------
12936 -- Is_Variant_Record --
12937 -----------------------
12939 function Is_Variant_Record (T : Entity_Id) return Boolean is
12941 return Nkind (Parent (T)) = N_Full_Type_Declaration
12942 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
12943 and then Present (Component_List (Type_Definition (Parent (T))))
12946 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
12947 end Is_Variant_Record;
12949 -- Start of processing for Create_Constrained_Components
12952 pragma Assert (Subt /= Base_Type (Subt));
12953 pragma Assert (Typ = Base_Type (Typ));
12955 Set_First_Entity (Subt, Empty);
12956 Set_Last_Entity (Subt, Empty);
12958 -- Check whether constraint is fully static, in which case we can
12959 -- optimize the list of components.
12961 Discr_Val := First_Elmt (Constraints);
12962 while Present (Discr_Val) loop
12963 if not Is_OK_Static_Expression (Node (Discr_Val)) then
12964 Is_Static := False;
12968 Next_Elmt (Discr_Val);
12971 Set_Has_Static_Discriminants (Subt, Is_Static);
12975 -- Inherit the discriminants of the parent type
12977 Add_Discriminants : declare
12983 Old_C := First_Discriminant (Typ);
12985 while Present (Old_C) loop
12986 Num_Disc := Num_Disc + 1;
12987 New_C := Create_Component (Old_C);
12988 Set_Is_Public (New_C, Is_Public (Subt));
12989 Next_Discriminant (Old_C);
12992 -- For an untagged derived subtype, the number of discriminants may
12993 -- be smaller than the number of inherited discriminants, because
12994 -- several of them may be renamed by a single new discriminant or
12995 -- constrained. In this case, add the hidden discriminants back into
12996 -- the subtype, because they need to be present if the optimizer of
12997 -- the GCC 4.x back-end decides to break apart assignments between
12998 -- objects using the parent view into member-wise assignments.
13002 if Is_Derived_Type (Typ)
13003 and then not Is_Tagged_Type (Typ)
13005 Old_C := First_Stored_Discriminant (Typ);
13007 while Present (Old_C) loop
13008 Num_Gird := Num_Gird + 1;
13009 Next_Stored_Discriminant (Old_C);
13013 if Num_Gird > Num_Disc then
13015 -- Find out multiple uses of new discriminants, and add hidden
13016 -- components for the extra renamed discriminants. We recognize
13017 -- multiple uses through the Corresponding_Discriminant of a
13018 -- new discriminant: if it constrains several old discriminants,
13019 -- this field points to the last one in the parent type. The
13020 -- stored discriminants of the derived type have the same name
13021 -- as those of the parent.
13025 New_Discr : Entity_Id;
13026 Old_Discr : Entity_Id;
13029 Constr := First_Elmt (Stored_Constraint (Typ));
13030 Old_Discr := First_Stored_Discriminant (Typ);
13031 while Present (Constr) loop
13032 if Is_Entity_Name (Node (Constr))
13033 and then Ekind (Entity (Node (Constr))) = E_Discriminant
13035 New_Discr := Entity (Node (Constr));
13037 if Chars (Corresponding_Discriminant (New_Discr)) /=
13040 -- The new discriminant has been used to rename a
13041 -- subsequent old discriminant. Introduce a shadow
13042 -- component for the current old discriminant.
13044 New_C := Create_Component (Old_Discr);
13045 Set_Original_Record_Component (New_C, Old_Discr);
13049 -- The constraint has eliminated the old discriminant.
13050 -- Introduce a shadow component.
13052 New_C := Create_Component (Old_Discr);
13053 Set_Original_Record_Component (New_C, Old_Discr);
13056 Next_Elmt (Constr);
13057 Next_Stored_Discriminant (Old_Discr);
13061 end Add_Discriminants;
13064 and then Is_Variant_Record (Typ)
13066 Collect_Fixed_Components (Typ);
13068 Gather_Components (
13070 Component_List (Type_Definition (Parent (Typ))),
13071 Governed_By => Assoc_List,
13073 Report_Errors => Errors);
13074 pragma Assert (not Errors);
13076 Create_All_Components;
13078 -- If the subtype declaration is created for a tagged type derivation
13079 -- with constraints, we retrieve the record definition of the parent
13080 -- type to select the components of the proper variant.
13083 and then Is_Tagged_Type (Typ)
13084 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
13086 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
13087 and then Is_Variant_Record (Parent_Type)
13089 Collect_Fixed_Components (Typ);
13091 Gather_Components (
13093 Component_List (Type_Definition (Parent (Parent_Type))),
13094 Governed_By => Assoc_List,
13096 Report_Errors => Errors);
13097 pragma Assert (not Errors);
13099 -- If the tagged derivation has a type extension, collect all the
13100 -- new components therein.
13103 (Record_Extension_Part (Type_Definition (Parent (Typ))))
13105 Old_C := First_Component (Typ);
13106 while Present (Old_C) loop
13107 if Original_Record_Component (Old_C) = Old_C
13108 and then Chars (Old_C) /= Name_uTag
13109 and then Chars (Old_C) /= Name_uParent
13111 Append_Elmt (Old_C, Comp_List);
13114 Next_Component (Old_C);
13118 Create_All_Components;
13121 -- If discriminants are not static, or if this is a multi-level type
13122 -- extension, we have to include all components of the parent type.
13124 Old_C := First_Component (Typ);
13125 while Present (Old_C) loop
13126 New_C := Create_Component (Old_C);
13130 Constrain_Component_Type
13131 (Old_C, Subt, Decl_Node, Typ, Constraints));
13132 Set_Is_Public (New_C, Is_Public (Subt));
13134 Next_Component (Old_C);
13139 end Create_Constrained_Components;
13141 ------------------------------------------
13142 -- Decimal_Fixed_Point_Type_Declaration --
13143 ------------------------------------------
13145 procedure Decimal_Fixed_Point_Type_Declaration
13149 Loc : constant Source_Ptr := Sloc (Def);
13150 Digs_Expr : constant Node_Id := Digits_Expression (Def);
13151 Delta_Expr : constant Node_Id := Delta_Expression (Def);
13152 Implicit_Base : Entity_Id;
13159 Check_SPARK_Restriction
13160 ("decimal fixed point type is not allowed", Def);
13161 Check_Restriction (No_Fixed_Point, Def);
13163 -- Create implicit base type
13166 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
13167 Set_Etype (Implicit_Base, Implicit_Base);
13169 -- Analyze and process delta expression
13171 Analyze_And_Resolve (Delta_Expr, Universal_Real);
13173 Check_Delta_Expression (Delta_Expr);
13174 Delta_Val := Expr_Value_R (Delta_Expr);
13176 -- Check delta is power of 10, and determine scale value from it
13182 Scale_Val := Uint_0;
13185 if Val < Ureal_1 then
13186 while Val < Ureal_1 loop
13187 Val := Val * Ureal_10;
13188 Scale_Val := Scale_Val + 1;
13191 if Scale_Val > 18 then
13192 Error_Msg_N ("scale exceeds maximum value of 18", Def);
13193 Scale_Val := UI_From_Int (+18);
13197 while Val > Ureal_1 loop
13198 Val := Val / Ureal_10;
13199 Scale_Val := Scale_Val - 1;
13202 if Scale_Val < -18 then
13203 Error_Msg_N ("scale is less than minimum value of -18", Def);
13204 Scale_Val := UI_From_Int (-18);
13208 if Val /= Ureal_1 then
13209 Error_Msg_N ("delta expression must be a power of 10", Def);
13210 Delta_Val := Ureal_10 ** (-Scale_Val);
13214 -- Set delta, scale and small (small = delta for decimal type)
13216 Set_Delta_Value (Implicit_Base, Delta_Val);
13217 Set_Scale_Value (Implicit_Base, Scale_Val);
13218 Set_Small_Value (Implicit_Base, Delta_Val);
13220 -- Analyze and process digits expression
13222 Analyze_And_Resolve (Digs_Expr, Any_Integer);
13223 Check_Digits_Expression (Digs_Expr);
13224 Digs_Val := Expr_Value (Digs_Expr);
13226 if Digs_Val > 18 then
13227 Digs_Val := UI_From_Int (+18);
13228 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
13231 Set_Digits_Value (Implicit_Base, Digs_Val);
13232 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
13234 -- Set range of base type from digits value for now. This will be
13235 -- expanded to represent the true underlying base range by Freeze.
13237 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
13239 -- Note: We leave size as zero for now, size will be set at freeze
13240 -- time. We have to do this for ordinary fixed-point, because the size
13241 -- depends on the specified small, and we might as well do the same for
13242 -- decimal fixed-point.
13244 pragma Assert (Esize (Implicit_Base) = Uint_0);
13246 -- If there are bounds given in the declaration use them as the
13247 -- bounds of the first named subtype.
13249 if Present (Real_Range_Specification (Def)) then
13251 RRS : constant Node_Id := Real_Range_Specification (Def);
13252 Low : constant Node_Id := Low_Bound (RRS);
13253 High : constant Node_Id := High_Bound (RRS);
13258 Analyze_And_Resolve (Low, Any_Real);
13259 Analyze_And_Resolve (High, Any_Real);
13260 Check_Real_Bound (Low);
13261 Check_Real_Bound (High);
13262 Low_Val := Expr_Value_R (Low);
13263 High_Val := Expr_Value_R (High);
13265 if Low_Val < (-Bound_Val) then
13267 ("range low bound too small for digits value", Low);
13268 Low_Val := -Bound_Val;
13271 if High_Val > Bound_Val then
13273 ("range high bound too large for digits value", High);
13274 High_Val := Bound_Val;
13277 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
13280 -- If no explicit range, use range that corresponds to given
13281 -- digits value. This will end up as the final range for the
13285 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
13288 -- Complete entity for first subtype
13290 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
13291 Set_Etype (T, Implicit_Base);
13292 Set_Size_Info (T, Implicit_Base);
13293 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
13294 Set_Digits_Value (T, Digs_Val);
13295 Set_Delta_Value (T, Delta_Val);
13296 Set_Small_Value (T, Delta_Val);
13297 Set_Scale_Value (T, Scale_Val);
13298 Set_Is_Constrained (T);
13299 end Decimal_Fixed_Point_Type_Declaration;
13301 -----------------------------------
13302 -- Derive_Progenitor_Subprograms --
13303 -----------------------------------
13305 procedure Derive_Progenitor_Subprograms
13306 (Parent_Type : Entity_Id;
13307 Tagged_Type : Entity_Id)
13312 Iface_Elmt : Elmt_Id;
13313 Iface_Subp : Entity_Id;
13314 New_Subp : Entity_Id := Empty;
13315 Prim_Elmt : Elmt_Id;
13320 pragma Assert (Ada_Version >= Ada_2005
13321 and then Is_Record_Type (Tagged_Type)
13322 and then Is_Tagged_Type (Tagged_Type)
13323 and then Has_Interfaces (Tagged_Type));
13325 -- Step 1: Transfer to the full-view primitives associated with the
13326 -- partial-view that cover interface primitives. Conceptually this
13327 -- work should be done later by Process_Full_View; done here to
13328 -- simplify its implementation at later stages. It can be safely
13329 -- done here because interfaces must be visible in the partial and
13330 -- private view (RM 7.3(7.3/2)).
13332 -- Small optimization: This work is only required if the parent may
13333 -- have entities whose Alias attribute reference an interface primitive.
13334 -- Such a situation may occur if the parent is an abstract type and the
13335 -- primitive has not been yet overridden or if the parent is a generic
13336 -- formal type covering interfaces.
13338 -- If the tagged type is not abstract, it cannot have abstract
13339 -- primitives (the only entities in the list of primitives of
13340 -- non-abstract tagged types that can reference abstract primitives
13341 -- through its Alias attribute are the internal entities that have
13342 -- attribute Interface_Alias, and these entities are generated later
13343 -- by Add_Internal_Interface_Entities).
13345 if In_Private_Part (Current_Scope)
13346 and then (Is_Abstract_Type (Parent_Type)
13348 Is_Generic_Type (Parent_Type))
13350 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
13351 while Present (Elmt) loop
13352 Subp := Node (Elmt);
13354 -- At this stage it is not possible to have entities in the list
13355 -- of primitives that have attribute Interface_Alias.
13357 pragma Assert (No (Interface_Alias (Subp)));
13359 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
13361 if Is_Interface (Typ) then
13362 E := Find_Primitive_Covering_Interface
13363 (Tagged_Type => Tagged_Type,
13364 Iface_Prim => Subp);
13367 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
13369 Replace_Elmt (Elmt, E);
13370 Remove_Homonym (Subp);
13378 -- Step 2: Add primitives of progenitors that are not implemented by
13379 -- parents of Tagged_Type.
13381 if Present (Interfaces (Base_Type (Tagged_Type))) then
13382 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
13383 while Present (Iface_Elmt) loop
13384 Iface := Node (Iface_Elmt);
13386 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
13387 while Present (Prim_Elmt) loop
13388 Iface_Subp := Node (Prim_Elmt);
13390 -- Exclude derivation of predefined primitives except those
13391 -- that come from source, or are inherited from one that comes
13392 -- from source. Required to catch declarations of equality
13393 -- operators of interfaces. For example:
13395 -- type Iface is interface;
13396 -- function "=" (Left, Right : Iface) return Boolean;
13398 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
13399 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
13401 E := Find_Primitive_Covering_Interface
13402 (Tagged_Type => Tagged_Type,
13403 Iface_Prim => Iface_Subp);
13405 -- If not found we derive a new primitive leaving its alias
13406 -- attribute referencing the interface primitive.
13410 (New_Subp, Iface_Subp, Tagged_Type, Iface);
13412 -- Ada 2012 (AI05-0197): If the covering primitive's name
13413 -- differs from the name of the interface primitive then it
13414 -- is a private primitive inherited from a parent type. In
13415 -- such case, given that Tagged_Type covers the interface,
13416 -- the inherited private primitive becomes visible. For such
13417 -- purpose we add a new entity that renames the inherited
13418 -- private primitive.
13420 elsif Chars (E) /= Chars (Iface_Subp) then
13421 pragma Assert (Has_Suffix (E, 'P'));
13423 (New_Subp, Iface_Subp, Tagged_Type, Iface);
13424 Set_Alias (New_Subp, E);
13425 Set_Is_Abstract_Subprogram (New_Subp,
13426 Is_Abstract_Subprogram (E));
13428 -- Propagate to the full view interface entities associated
13429 -- with the partial view.
13431 elsif In_Private_Part (Current_Scope)
13432 and then Present (Alias (E))
13433 and then Alias (E) = Iface_Subp
13435 List_Containing (Parent (E)) /=
13436 Private_Declarations
13438 (Unit_Declaration_Node (Current_Scope)))
13440 Append_Elmt (E, Primitive_Operations (Tagged_Type));
13444 Next_Elmt (Prim_Elmt);
13447 Next_Elmt (Iface_Elmt);
13450 end Derive_Progenitor_Subprograms;
13452 -----------------------
13453 -- Derive_Subprogram --
13454 -----------------------
13456 procedure Derive_Subprogram
13457 (New_Subp : in out Entity_Id;
13458 Parent_Subp : Entity_Id;
13459 Derived_Type : Entity_Id;
13460 Parent_Type : Entity_Id;
13461 Actual_Subp : Entity_Id := Empty)
13463 Formal : Entity_Id;
13464 -- Formal parameter of parent primitive operation
13466 Formal_Of_Actual : Entity_Id;
13467 -- Formal parameter of actual operation, when the derivation is to
13468 -- create a renaming for a primitive operation of an actual in an
13471 New_Formal : Entity_Id;
13472 -- Formal of inherited operation
13474 Visible_Subp : Entity_Id := Parent_Subp;
13476 function Is_Private_Overriding return Boolean;
13477 -- If Subp is a private overriding of a visible operation, the inherited
13478 -- operation derives from the overridden op (even though its body is the
13479 -- overriding one) and the inherited operation is visible now. See
13480 -- sem_disp to see the full details of the handling of the overridden
13481 -- subprogram, which is removed from the list of primitive operations of
13482 -- the type. The overridden subprogram is saved locally in Visible_Subp,
13483 -- and used to diagnose abstract operations that need overriding in the
13486 procedure Replace_Type (Id, New_Id : Entity_Id);
13487 -- When the type is an anonymous access type, create a new access type
13488 -- designating the derived type.
13490 procedure Set_Derived_Name;
13491 -- This procedure sets the appropriate Chars name for New_Subp. This
13492 -- is normally just a copy of the parent name. An exception arises for
13493 -- type support subprograms, where the name is changed to reflect the
13494 -- name of the derived type, e.g. if type foo is derived from type bar,
13495 -- then a procedure barDA is derived with a name fooDA.
13497 ---------------------------
13498 -- Is_Private_Overriding --
13499 ---------------------------
13501 function Is_Private_Overriding return Boolean is
13505 -- If the parent is not a dispatching operation there is no
13506 -- need to investigate overridings
13508 if not Is_Dispatching_Operation (Parent_Subp) then
13512 -- The visible operation that is overridden is a homonym of the
13513 -- parent subprogram. We scan the homonym chain to find the one
13514 -- whose alias is the subprogram we are deriving.
13516 Prev := Current_Entity (Parent_Subp);
13517 while Present (Prev) loop
13518 if Ekind (Prev) = Ekind (Parent_Subp)
13519 and then Alias (Prev) = Parent_Subp
13520 and then Scope (Parent_Subp) = Scope (Prev)
13521 and then not Is_Hidden (Prev)
13523 Visible_Subp := Prev;
13527 Prev := Homonym (Prev);
13531 end Is_Private_Overriding;
13537 procedure Replace_Type (Id, New_Id : Entity_Id) is
13538 Acc_Type : Entity_Id;
13539 Par : constant Node_Id := Parent (Derived_Type);
13542 -- When the type is an anonymous access type, create a new access
13543 -- type designating the derived type. This itype must be elaborated
13544 -- at the point of the derivation, not on subsequent calls that may
13545 -- be out of the proper scope for Gigi, so we insert a reference to
13546 -- it after the derivation.
13548 if Ekind (Etype (Id)) = E_Anonymous_Access_Type then
13550 Desig_Typ : Entity_Id := Designated_Type (Etype (Id));
13553 if Ekind (Desig_Typ) = E_Record_Type_With_Private
13554 and then Present (Full_View (Desig_Typ))
13555 and then not Is_Private_Type (Parent_Type)
13557 Desig_Typ := Full_View (Desig_Typ);
13560 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
13562 -- Ada 2005 (AI-251): Handle also derivations of abstract
13563 -- interface primitives.
13565 or else (Is_Interface (Desig_Typ)
13566 and then not Is_Class_Wide_Type (Desig_Typ))
13568 Acc_Type := New_Copy (Etype (Id));
13569 Set_Etype (Acc_Type, Acc_Type);
13570 Set_Scope (Acc_Type, New_Subp);
13572 -- Set size of anonymous access type. If we have an access
13573 -- to an unconstrained array, this is a fat pointer, so it
13574 -- is sizes at twice addtress size.
13576 if Is_Array_Type (Desig_Typ)
13577 and then not Is_Constrained (Desig_Typ)
13579 Init_Size (Acc_Type, 2 * System_Address_Size);
13581 -- Other cases use a thin pointer
13584 Init_Size (Acc_Type, System_Address_Size);
13587 -- Set remaining characterstics of anonymous access type
13589 Init_Alignment (Acc_Type);
13590 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
13592 Set_Etype (New_Id, Acc_Type);
13593 Set_Scope (New_Id, New_Subp);
13595 -- Create a reference to it
13597 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
13600 Set_Etype (New_Id, Etype (Id));
13604 elsif Base_Type (Etype (Id)) = Base_Type (Parent_Type)
13606 (Ekind (Etype (Id)) = E_Record_Type_With_Private
13607 and then Present (Full_View (Etype (Id)))
13609 Base_Type (Full_View (Etype (Id))) = Base_Type (Parent_Type))
13611 -- Constraint checks on formals are generated during expansion,
13612 -- based on the signature of the original subprogram. The bounds
13613 -- of the derived type are not relevant, and thus we can use
13614 -- the base type for the formals. However, the return type may be
13615 -- used in a context that requires that the proper static bounds
13616 -- be used (a case statement, for example) and for those cases
13617 -- we must use the derived type (first subtype), not its base.
13619 -- If the derived_type_definition has no constraints, we know that
13620 -- the derived type has the same constraints as the first subtype
13621 -- of the parent, and we can also use it rather than its base,
13622 -- which can lead to more efficient code.
13624 if Etype (Id) = Parent_Type then
13625 if Is_Scalar_Type (Parent_Type)
13627 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
13629 Set_Etype (New_Id, Derived_Type);
13631 elsif Nkind (Par) = N_Full_Type_Declaration
13633 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
13636 (Subtype_Indication (Type_Definition (Par)))
13638 Set_Etype (New_Id, Derived_Type);
13641 Set_Etype (New_Id, Base_Type (Derived_Type));
13645 Set_Etype (New_Id, Base_Type (Derived_Type));
13649 Set_Etype (New_Id, Etype (Id));
13653 ----------------------
13654 -- Set_Derived_Name --
13655 ----------------------
13657 procedure Set_Derived_Name is
13658 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
13660 if Nm = TSS_Null then
13661 Set_Chars (New_Subp, Chars (Parent_Subp));
13663 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
13665 end Set_Derived_Name;
13667 -- Start of processing for Derive_Subprogram
13671 New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
13672 Set_Ekind (New_Subp, Ekind (Parent_Subp));
13673 Set_Contract (New_Subp, Make_Contract (Sloc (New_Subp)));
13675 -- Check whether the inherited subprogram is a private operation that
13676 -- should be inherited but not yet made visible. Such subprograms can
13677 -- become visible at a later point (e.g., the private part of a public
13678 -- child unit) via Declare_Inherited_Private_Subprograms. If the
13679 -- following predicate is true, then this is not such a private
13680 -- operation and the subprogram simply inherits the name of the parent
13681 -- subprogram. Note the special check for the names of controlled
13682 -- operations, which are currently exempted from being inherited with
13683 -- a hidden name because they must be findable for generation of
13684 -- implicit run-time calls.
13686 if not Is_Hidden (Parent_Subp)
13687 or else Is_Internal (Parent_Subp)
13688 or else Is_Private_Overriding
13689 or else Is_Internal_Name (Chars (Parent_Subp))
13690 or else Nam_In (Chars (Parent_Subp), Name_Initialize,
13696 -- An inherited dispatching equality will be overridden by an internally
13697 -- generated one, or by an explicit one, so preserve its name and thus
13698 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
13699 -- private operation it may become invisible if the full view has
13700 -- progenitors, and the dispatch table will be malformed.
13701 -- We check that the type is limited to handle the anomalous declaration
13702 -- of Limited_Controlled, which is derived from a non-limited type, and
13703 -- which is handled specially elsewhere as well.
13705 elsif Chars (Parent_Subp) = Name_Op_Eq
13706 and then Is_Dispatching_Operation (Parent_Subp)
13707 and then Etype (Parent_Subp) = Standard_Boolean
13708 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
13710 Etype (First_Formal (Parent_Subp)) =
13711 Etype (Next_Formal (First_Formal (Parent_Subp)))
13715 -- If parent is hidden, this can be a regular derivation if the
13716 -- parent is immediately visible in a non-instantiating context,
13717 -- or if we are in the private part of an instance. This test
13718 -- should still be refined ???
13720 -- The test for In_Instance_Not_Visible avoids inheriting the derived
13721 -- operation as a non-visible operation in cases where the parent
13722 -- subprogram might not be visible now, but was visible within the
13723 -- original generic, so it would be wrong to make the inherited
13724 -- subprogram non-visible now. (Not clear if this test is fully
13725 -- correct; are there any cases where we should declare the inherited
13726 -- operation as not visible to avoid it being overridden, e.g., when
13727 -- the parent type is a generic actual with private primitives ???)
13729 -- (they should be treated the same as other private inherited
13730 -- subprograms, but it's not clear how to do this cleanly). ???
13732 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
13733 and then Is_Immediately_Visible (Parent_Subp)
13734 and then not In_Instance)
13735 or else In_Instance_Not_Visible
13739 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
13740 -- overrides an interface primitive because interface primitives
13741 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
13743 elsif Ada_Version >= Ada_2005
13744 and then Is_Dispatching_Operation (Parent_Subp)
13745 and then Covers_Some_Interface (Parent_Subp)
13749 -- Otherwise, the type is inheriting a private operation, so enter
13750 -- it with a special name so it can't be overridden.
13753 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
13756 Set_Parent (New_Subp, Parent (Derived_Type));
13758 if Present (Actual_Subp) then
13759 Replace_Type (Actual_Subp, New_Subp);
13761 Replace_Type (Parent_Subp, New_Subp);
13764 Conditional_Delay (New_Subp, Parent_Subp);
13766 -- If we are creating a renaming for a primitive operation of an
13767 -- actual of a generic derived type, we must examine the signature
13768 -- of the actual primitive, not that of the generic formal, which for
13769 -- example may be an interface. However the name and initial value
13770 -- of the inherited operation are those of the formal primitive.
13772 Formal := First_Formal (Parent_Subp);
13774 if Present (Actual_Subp) then
13775 Formal_Of_Actual := First_Formal (Actual_Subp);
13777 Formal_Of_Actual := Empty;
13780 while Present (Formal) loop
13781 New_Formal := New_Copy (Formal);
13783 -- Normally we do not go copying parents, but in the case of
13784 -- formals, we need to link up to the declaration (which is the
13785 -- parameter specification), and it is fine to link up to the
13786 -- original formal's parameter specification in this case.
13788 Set_Parent (New_Formal, Parent (Formal));
13789 Append_Entity (New_Formal, New_Subp);
13791 if Present (Formal_Of_Actual) then
13792 Replace_Type (Formal_Of_Actual, New_Formal);
13793 Next_Formal (Formal_Of_Actual);
13795 Replace_Type (Formal, New_Formal);
13798 Next_Formal (Formal);
13801 -- If this derivation corresponds to a tagged generic actual, then
13802 -- primitive operations rename those of the actual. Otherwise the
13803 -- primitive operations rename those of the parent type, If the parent
13804 -- renames an intrinsic operator, so does the new subprogram. We except
13805 -- concatenation, which is always properly typed, and does not get
13806 -- expanded as other intrinsic operations.
13808 if No (Actual_Subp) then
13809 if Is_Intrinsic_Subprogram (Parent_Subp) then
13810 Set_Is_Intrinsic_Subprogram (New_Subp);
13812 if Present (Alias (Parent_Subp))
13813 and then Chars (Parent_Subp) /= Name_Op_Concat
13815 Set_Alias (New_Subp, Alias (Parent_Subp));
13817 Set_Alias (New_Subp, Parent_Subp);
13821 Set_Alias (New_Subp, Parent_Subp);
13825 Set_Alias (New_Subp, Actual_Subp);
13828 -- Derived subprograms of a tagged type must inherit the convention
13829 -- of the parent subprogram (a requirement of AI-117). Derived
13830 -- subprograms of untagged types simply get convention Ada by default.
13832 -- If the derived type is a tagged generic formal type with unknown
13833 -- discriminants, its convention is intrinsic (RM 6.3.1 (8)).
13835 -- However, if the type is derived from a generic formal, the further
13836 -- inherited subprogram has the convention of the non-generic ancestor.
13837 -- Otherwise there would be no way to override the operation.
13838 -- (This is subject to forthcoming ARG discussions).
13840 if Is_Tagged_Type (Derived_Type) then
13841 if Is_Generic_Type (Derived_Type)
13842 and then Has_Unknown_Discriminants (Derived_Type)
13844 Set_Convention (New_Subp, Convention_Intrinsic);
13847 if Is_Generic_Type (Parent_Type)
13848 and then Has_Unknown_Discriminants (Parent_Type)
13850 Set_Convention (New_Subp, Convention (Alias (Parent_Subp)));
13852 Set_Convention (New_Subp, Convention (Parent_Subp));
13857 -- Predefined controlled operations retain their name even if the parent
13858 -- is hidden (see above), but they are not primitive operations if the
13859 -- ancestor is not visible, for example if the parent is a private
13860 -- extension completed with a controlled extension. Note that a full
13861 -- type that is controlled can break privacy: the flag Is_Controlled is
13862 -- set on both views of the type.
13864 if Is_Controlled (Parent_Type)
13865 and then Nam_In (Chars (Parent_Subp), Name_Initialize,
13868 and then Is_Hidden (Parent_Subp)
13869 and then not Is_Visibly_Controlled (Parent_Type)
13871 Set_Is_Hidden (New_Subp);
13874 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
13875 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
13877 if Ekind (Parent_Subp) = E_Procedure then
13878 Set_Is_Valued_Procedure
13879 (New_Subp, Is_Valued_Procedure (Parent_Subp));
13881 Set_Has_Controlling_Result
13882 (New_Subp, Has_Controlling_Result (Parent_Subp));
13885 -- No_Return must be inherited properly. If this is overridden in the
13886 -- case of a dispatching operation, then a check is made in Sem_Disp
13887 -- that the overriding operation is also No_Return (no such check is
13888 -- required for the case of non-dispatching operation.
13890 Set_No_Return (New_Subp, No_Return (Parent_Subp));
13892 -- A derived function with a controlling result is abstract. If the
13893 -- Derived_Type is a nonabstract formal generic derived type, then
13894 -- inherited operations are not abstract: the required check is done at
13895 -- instantiation time. If the derivation is for a generic actual, the
13896 -- function is not abstract unless the actual is.
13898 if Is_Generic_Type (Derived_Type)
13899 and then not Is_Abstract_Type (Derived_Type)
13903 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
13904 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
13906 elsif Ada_Version >= Ada_2005
13907 and then (Is_Abstract_Subprogram (Alias (New_Subp))
13908 or else (Is_Tagged_Type (Derived_Type)
13909 and then Etype (New_Subp) = Derived_Type
13910 and then not Is_Null_Extension (Derived_Type))
13911 or else (Is_Tagged_Type (Derived_Type)
13912 and then Ekind (Etype (New_Subp)) =
13913 E_Anonymous_Access_Type
13914 and then Designated_Type (Etype (New_Subp)) =
13916 and then not Is_Null_Extension (Derived_Type)))
13917 and then No (Actual_Subp)
13919 if not Is_Tagged_Type (Derived_Type)
13920 or else Is_Abstract_Type (Derived_Type)
13921 or else Is_Abstract_Subprogram (Alias (New_Subp))
13923 Set_Is_Abstract_Subprogram (New_Subp);
13925 Set_Requires_Overriding (New_Subp);
13928 elsif Ada_Version < Ada_2005
13929 and then (Is_Abstract_Subprogram (Alias (New_Subp))
13930 or else (Is_Tagged_Type (Derived_Type)
13931 and then Etype (New_Subp) = Derived_Type
13932 and then No (Actual_Subp)))
13934 Set_Is_Abstract_Subprogram (New_Subp);
13936 -- AI05-0097 : an inherited operation that dispatches on result is
13937 -- abstract if the derived type is abstract, even if the parent type
13938 -- is concrete and the derived type is a null extension.
13940 elsif Has_Controlling_Result (Alias (New_Subp))
13941 and then Is_Abstract_Type (Etype (New_Subp))
13943 Set_Is_Abstract_Subprogram (New_Subp);
13945 -- Finally, if the parent type is abstract we must verify that all
13946 -- inherited operations are either non-abstract or overridden, or that
13947 -- the derived type itself is abstract (this check is performed at the
13948 -- end of a package declaration, in Check_Abstract_Overriding). A
13949 -- private overriding in the parent type will not be visible in the
13950 -- derivation if we are not in an inner package or in a child unit of
13951 -- the parent type, in which case the abstractness of the inherited
13952 -- operation is carried to the new subprogram.
13954 elsif Is_Abstract_Type (Parent_Type)
13955 and then not In_Open_Scopes (Scope (Parent_Type))
13956 and then Is_Private_Overriding
13957 and then Is_Abstract_Subprogram (Visible_Subp)
13959 if No (Actual_Subp) then
13960 Set_Alias (New_Subp, Visible_Subp);
13961 Set_Is_Abstract_Subprogram (New_Subp, True);
13964 -- If this is a derivation for an instance of a formal derived
13965 -- type, abstractness comes from the primitive operation of the
13966 -- actual, not from the operation inherited from the ancestor.
13968 Set_Is_Abstract_Subprogram
13969 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
13973 New_Overloaded_Entity (New_Subp, Derived_Type);
13975 -- Check for case of a derived subprogram for the instantiation of a
13976 -- formal derived tagged type, if so mark the subprogram as dispatching
13977 -- and inherit the dispatching attributes of the actual subprogram. The
13978 -- derived subprogram is effectively renaming of the actual subprogram,
13979 -- so it needs to have the same attributes as the actual.
13981 if Present (Actual_Subp)
13982 and then Is_Dispatching_Operation (Actual_Subp)
13984 Set_Is_Dispatching_Operation (New_Subp);
13986 if Present (DTC_Entity (Actual_Subp)) then
13987 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
13988 Set_DT_Position (New_Subp, DT_Position (Actual_Subp));
13992 -- Indicate that a derived subprogram does not require a body and that
13993 -- it does not require processing of default expressions.
13995 Set_Has_Completion (New_Subp);
13996 Set_Default_Expressions_Processed (New_Subp);
13998 if Ekind (New_Subp) = E_Function then
13999 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
14001 end Derive_Subprogram;
14003 ------------------------
14004 -- Derive_Subprograms --
14005 ------------------------
14007 procedure Derive_Subprograms
14008 (Parent_Type : Entity_Id;
14009 Derived_Type : Entity_Id;
14010 Generic_Actual : Entity_Id := Empty)
14012 Op_List : constant Elist_Id :=
14013 Collect_Primitive_Operations (Parent_Type);
14015 function Check_Derived_Type return Boolean;
14016 -- Check that all the entities derived from Parent_Type are found in
14017 -- the list of primitives of Derived_Type exactly in the same order.
14019 procedure Derive_Interface_Subprogram
14020 (New_Subp : in out Entity_Id;
14022 Actual_Subp : Entity_Id);
14023 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
14024 -- (which is an interface primitive). If Generic_Actual is present then
14025 -- Actual_Subp is the actual subprogram corresponding with the generic
14026 -- subprogram Subp.
14028 function Check_Derived_Type return Boolean is
14032 New_Subp : Entity_Id;
14037 -- Traverse list of entities in the current scope searching for
14038 -- an incomplete type whose full-view is derived type
14040 E := First_Entity (Scope (Derived_Type));
14041 while Present (E) and then E /= Derived_Type loop
14042 if Ekind (E) = E_Incomplete_Type
14043 and then Present (Full_View (E))
14044 and then Full_View (E) = Derived_Type
14046 -- Disable this test if Derived_Type completes an incomplete
14047 -- type because in such case more primitives can be added
14048 -- later to the list of primitives of Derived_Type by routine
14049 -- Process_Incomplete_Dependents
14054 E := Next_Entity (E);
14057 List := Collect_Primitive_Operations (Derived_Type);
14058 Elmt := First_Elmt (List);
14060 Op_Elmt := First_Elmt (Op_List);
14061 while Present (Op_Elmt) loop
14062 Subp := Node (Op_Elmt);
14063 New_Subp := Node (Elmt);
14065 -- At this early stage Derived_Type has no entities with attribute
14066 -- Interface_Alias. In addition, such primitives are always
14067 -- located at the end of the list of primitives of Parent_Type.
14068 -- Therefore, if found we can safely stop processing pending
14071 exit when Present (Interface_Alias (Subp));
14073 -- Handle hidden entities
14075 if not Is_Predefined_Dispatching_Operation (Subp)
14076 and then Is_Hidden (Subp)
14078 if Present (New_Subp)
14079 and then Primitive_Names_Match (Subp, New_Subp)
14085 if not Present (New_Subp)
14086 or else Ekind (Subp) /= Ekind (New_Subp)
14087 or else not Primitive_Names_Match (Subp, New_Subp)
14095 Next_Elmt (Op_Elmt);
14099 end Check_Derived_Type;
14101 ---------------------------------
14102 -- Derive_Interface_Subprogram --
14103 ---------------------------------
14105 procedure Derive_Interface_Subprogram
14106 (New_Subp : in out Entity_Id;
14108 Actual_Subp : Entity_Id)
14110 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
14111 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
14114 pragma Assert (Is_Interface (Iface_Type));
14117 (New_Subp => New_Subp,
14118 Parent_Subp => Iface_Subp,
14119 Derived_Type => Derived_Type,
14120 Parent_Type => Iface_Type,
14121 Actual_Subp => Actual_Subp);
14123 -- Given that this new interface entity corresponds with a primitive
14124 -- of the parent that was not overridden we must leave it associated
14125 -- with its parent primitive to ensure that it will share the same
14126 -- dispatch table slot when overridden.
14128 if No (Actual_Subp) then
14129 Set_Alias (New_Subp, Subp);
14131 -- For instantiations this is not needed since the previous call to
14132 -- Derive_Subprogram leaves the entity well decorated.
14135 pragma Assert (Alias (New_Subp) = Actual_Subp);
14138 end Derive_Interface_Subprogram;
14142 Alias_Subp : Entity_Id;
14143 Act_List : Elist_Id;
14144 Act_Elmt : Elmt_Id;
14145 Act_Subp : Entity_Id := Empty;
14147 Need_Search : Boolean := False;
14148 New_Subp : Entity_Id := Empty;
14149 Parent_Base : Entity_Id;
14152 -- Start of processing for Derive_Subprograms
14155 if Ekind (Parent_Type) = E_Record_Type_With_Private
14156 and then Has_Discriminants (Parent_Type)
14157 and then Present (Full_View (Parent_Type))
14159 Parent_Base := Full_View (Parent_Type);
14161 Parent_Base := Parent_Type;
14164 if Present (Generic_Actual) then
14165 Act_List := Collect_Primitive_Operations (Generic_Actual);
14166 Act_Elmt := First_Elmt (Act_List);
14168 Act_List := No_Elist;
14169 Act_Elmt := No_Elmt;
14172 -- Derive primitives inherited from the parent. Note that if the generic
14173 -- actual is present, this is not really a type derivation, it is a
14174 -- completion within an instance.
14176 -- Case 1: Derived_Type does not implement interfaces
14178 if not Is_Tagged_Type (Derived_Type)
14179 or else (not Has_Interfaces (Derived_Type)
14180 and then not (Present (Generic_Actual)
14181 and then Has_Interfaces (Generic_Actual)))
14183 Elmt := First_Elmt (Op_List);
14184 while Present (Elmt) loop
14185 Subp := Node (Elmt);
14187 -- Literals are derived earlier in the process of building the
14188 -- derived type, and are skipped here.
14190 if Ekind (Subp) = E_Enumeration_Literal then
14193 -- The actual is a direct descendant and the common primitive
14194 -- operations appear in the same order.
14196 -- If the generic parent type is present, the derived type is an
14197 -- instance of a formal derived type, and within the instance its
14198 -- operations are those of the actual. We derive from the formal
14199 -- type but make the inherited operations aliases of the
14200 -- corresponding operations of the actual.
14203 pragma Assert (No (Node (Act_Elmt))
14204 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
14207 (Subp, Node (Act_Elmt),
14208 Skip_Controlling_Formals => True)));
14211 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
14213 if Present (Act_Elmt) then
14214 Next_Elmt (Act_Elmt);
14221 -- Case 2: Derived_Type implements interfaces
14224 -- If the parent type has no predefined primitives we remove
14225 -- predefined primitives from the list of primitives of generic
14226 -- actual to simplify the complexity of this algorithm.
14228 if Present (Generic_Actual) then
14230 Has_Predefined_Primitives : Boolean := False;
14233 -- Check if the parent type has predefined primitives
14235 Elmt := First_Elmt (Op_List);
14236 while Present (Elmt) loop
14237 Subp := Node (Elmt);
14239 if Is_Predefined_Dispatching_Operation (Subp)
14240 and then not Comes_From_Source (Ultimate_Alias (Subp))
14242 Has_Predefined_Primitives := True;
14249 -- Remove predefined primitives of Generic_Actual. We must use
14250 -- an auxiliary list because in case of tagged types the value
14251 -- returned by Collect_Primitive_Operations is the value stored
14252 -- in its Primitive_Operations attribute (and we don't want to
14253 -- modify its current contents).
14255 if not Has_Predefined_Primitives then
14257 Aux_List : constant Elist_Id := New_Elmt_List;
14260 Elmt := First_Elmt (Act_List);
14261 while Present (Elmt) loop
14262 Subp := Node (Elmt);
14264 if not Is_Predefined_Dispatching_Operation (Subp)
14265 or else Comes_From_Source (Subp)
14267 Append_Elmt (Subp, Aux_List);
14273 Act_List := Aux_List;
14277 Act_Elmt := First_Elmt (Act_List);
14278 Act_Subp := Node (Act_Elmt);
14282 -- Stage 1: If the generic actual is not present we derive the
14283 -- primitives inherited from the parent type. If the generic parent
14284 -- type is present, the derived type is an instance of a formal
14285 -- derived type, and within the instance its operations are those of
14286 -- the actual. We derive from the formal type but make the inherited
14287 -- operations aliases of the corresponding operations of the actual.
14289 Elmt := First_Elmt (Op_List);
14290 while Present (Elmt) loop
14291 Subp := Node (Elmt);
14292 Alias_Subp := Ultimate_Alias (Subp);
14294 -- Do not derive internal entities of the parent that link
14295 -- interface primitives with their covering primitive. These
14296 -- entities will be added to this type when frozen.
14298 if Present (Interface_Alias (Subp)) then
14302 -- If the generic actual is present find the corresponding
14303 -- operation in the generic actual. If the parent type is a
14304 -- direct ancestor of the derived type then, even if it is an
14305 -- interface, the operations are inherited from the primary
14306 -- dispatch table and are in the proper order. If we detect here
14307 -- that primitives are not in the same order we traverse the list
14308 -- of primitive operations of the actual to find the one that
14309 -- implements the interface primitive.
14313 (Present (Generic_Actual)
14314 and then Present (Act_Subp)
14316 (Primitive_Names_Match (Subp, Act_Subp)
14318 Type_Conformant (Subp, Act_Subp,
14319 Skip_Controlling_Formals => True)))
14321 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
14322 Use_Full_View => True));
14324 -- Remember that we need searching for all pending primitives
14326 Need_Search := True;
14328 -- Handle entities associated with interface primitives
14330 if Present (Alias_Subp)
14331 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
14332 and then not Is_Predefined_Dispatching_Operation (Subp)
14334 -- Search for the primitive in the homonym chain
14337 Find_Primitive_Covering_Interface
14338 (Tagged_Type => Generic_Actual,
14339 Iface_Prim => Alias_Subp);
14341 -- Previous search may not locate primitives covering
14342 -- interfaces defined in generics units or instantiations.
14343 -- (it fails if the covering primitive has formals whose
14344 -- type is also defined in generics or instantiations).
14345 -- In such case we search in the list of primitives of the
14346 -- generic actual for the internal entity that links the
14347 -- interface primitive and the covering primitive.
14350 and then Is_Generic_Type (Parent_Type)
14352 -- This code has been designed to handle only generic
14353 -- formals that implement interfaces that are defined
14354 -- in a generic unit or instantiation. If this code is
14355 -- needed for other cases we must review it because
14356 -- (given that it relies on Original_Location to locate
14357 -- the primitive of Generic_Actual that covers the
14358 -- interface) it could leave linked through attribute
14359 -- Alias entities of unrelated instantiations).
14363 (Scope (Find_Dispatching_Type (Alias_Subp)))
14365 Instantiation_Depth
14366 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
14369 Iface_Prim_Loc : constant Source_Ptr :=
14370 Original_Location (Sloc (Alias_Subp));
14377 First_Elmt (Primitive_Operations (Generic_Actual));
14379 Search : while Present (Elmt) loop
14380 Prim := Node (Elmt);
14382 if Present (Interface_Alias (Prim))
14383 and then Original_Location
14384 (Sloc (Interface_Alias (Prim))) =
14387 Act_Subp := Alias (Prim);
14396 pragma Assert (Present (Act_Subp)
14397 or else Is_Abstract_Type (Generic_Actual)
14398 or else Serious_Errors_Detected > 0);
14400 -- Handle predefined primitives plus the rest of user-defined
14404 Act_Elmt := First_Elmt (Act_List);
14405 while Present (Act_Elmt) loop
14406 Act_Subp := Node (Act_Elmt);
14408 exit when Primitive_Names_Match (Subp, Act_Subp)
14409 and then Type_Conformant
14411 Skip_Controlling_Formals => True)
14412 and then No (Interface_Alias (Act_Subp));
14414 Next_Elmt (Act_Elmt);
14417 if No (Act_Elmt) then
14423 -- Case 1: If the parent is a limited interface then it has the
14424 -- predefined primitives of synchronized interfaces. However, the
14425 -- actual type may be a non-limited type and hence it does not
14426 -- have such primitives.
14428 if Present (Generic_Actual)
14429 and then not Present (Act_Subp)
14430 and then Is_Limited_Interface (Parent_Base)
14431 and then Is_Predefined_Interface_Primitive (Subp)
14435 -- Case 2: Inherit entities associated with interfaces that were
14436 -- not covered by the parent type. We exclude here null interface
14437 -- primitives because they do not need special management.
14439 -- We also exclude interface operations that are renamings. If the
14440 -- subprogram is an explicit renaming of an interface primitive,
14441 -- it is a regular primitive operation, and the presence of its
14442 -- alias is not relevant: it has to be derived like any other
14445 elsif Present (Alias (Subp))
14446 and then Nkind (Unit_Declaration_Node (Subp)) /=
14447 N_Subprogram_Renaming_Declaration
14448 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
14450 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
14451 and then Null_Present (Parent (Alias_Subp)))
14453 -- If this is an abstract private type then we transfer the
14454 -- derivation of the interface primitive from the partial view
14455 -- to the full view. This is safe because all the interfaces
14456 -- must be visible in the partial view. Done to avoid adding
14457 -- a new interface derivation to the private part of the
14458 -- enclosing package; otherwise this new derivation would be
14459 -- decorated as hidden when the analysis of the enclosing
14460 -- package completes.
14462 if Is_Abstract_Type (Derived_Type)
14463 and then In_Private_Part (Current_Scope)
14464 and then Has_Private_Declaration (Derived_Type)
14467 Partial_View : Entity_Id;
14472 Partial_View := First_Entity (Current_Scope);
14474 exit when No (Partial_View)
14475 or else (Has_Private_Declaration (Partial_View)
14477 Full_View (Partial_View) = Derived_Type);
14479 Next_Entity (Partial_View);
14482 -- If the partial view was not found then the source code
14483 -- has errors and the derivation is not needed.
14485 if Present (Partial_View) then
14487 First_Elmt (Primitive_Operations (Partial_View));
14488 while Present (Elmt) loop
14489 Ent := Node (Elmt);
14491 if Present (Alias (Ent))
14492 and then Ultimate_Alias (Ent) = Alias (Subp)
14495 (Ent, Primitive_Operations (Derived_Type));
14502 -- If the interface primitive was not found in the
14503 -- partial view then this interface primitive was
14504 -- overridden. We add a derivation to activate in
14505 -- Derive_Progenitor_Subprograms the machinery to
14509 Derive_Interface_Subprogram
14510 (New_Subp => New_Subp,
14512 Actual_Subp => Act_Subp);
14517 Derive_Interface_Subprogram
14518 (New_Subp => New_Subp,
14520 Actual_Subp => Act_Subp);
14523 -- Case 3: Common derivation
14527 (New_Subp => New_Subp,
14528 Parent_Subp => Subp,
14529 Derived_Type => Derived_Type,
14530 Parent_Type => Parent_Base,
14531 Actual_Subp => Act_Subp);
14534 -- No need to update Act_Elm if we must search for the
14535 -- corresponding operation in the generic actual
14538 and then Present (Act_Elmt)
14540 Next_Elmt (Act_Elmt);
14541 Act_Subp := Node (Act_Elmt);
14548 -- Inherit additional operations from progenitors. If the derived
14549 -- type is a generic actual, there are not new primitive operations
14550 -- for the type because it has those of the actual, and therefore
14551 -- nothing needs to be done. The renamings generated above are not
14552 -- primitive operations, and their purpose is simply to make the
14553 -- proper operations visible within an instantiation.
14555 if No (Generic_Actual) then
14556 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
14560 -- Final check: Direct descendants must have their primitives in the
14561 -- same order. We exclude from this test untagged types and instances
14562 -- of formal derived types. We skip this test if we have already
14563 -- reported serious errors in the sources.
14565 pragma Assert (not Is_Tagged_Type (Derived_Type)
14566 or else Present (Generic_Actual)
14567 or else Serious_Errors_Detected > 0
14568 or else Check_Derived_Type);
14569 end Derive_Subprograms;
14571 --------------------------------
14572 -- Derived_Standard_Character --
14573 --------------------------------
14575 procedure Derived_Standard_Character
14577 Parent_Type : Entity_Id;
14578 Derived_Type : Entity_Id)
14580 Loc : constant Source_Ptr := Sloc (N);
14581 Def : constant Node_Id := Type_Definition (N);
14582 Indic : constant Node_Id := Subtype_Indication (Def);
14583 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
14584 Implicit_Base : constant Entity_Id :=
14586 (E_Enumeration_Type, N, Derived_Type, 'B');
14592 Discard_Node (Process_Subtype (Indic, N));
14594 Set_Etype (Implicit_Base, Parent_Base);
14595 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
14596 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
14598 Set_Is_Character_Type (Implicit_Base, True);
14599 Set_Has_Delayed_Freeze (Implicit_Base);
14601 -- The bounds of the implicit base are the bounds of the parent base.
14602 -- Note that their type is the parent base.
14604 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
14605 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
14607 Set_Scalar_Range (Implicit_Base,
14610 High_Bound => Hi));
14612 Conditional_Delay (Derived_Type, Parent_Type);
14614 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
14615 Set_Etype (Derived_Type, Implicit_Base);
14616 Set_Size_Info (Derived_Type, Parent_Type);
14618 if Unknown_RM_Size (Derived_Type) then
14619 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
14622 Set_Is_Character_Type (Derived_Type, True);
14624 if Nkind (Indic) /= N_Subtype_Indication then
14626 -- If no explicit constraint, the bounds are those
14627 -- of the parent type.
14629 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
14630 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
14631 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
14634 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
14636 -- Because the implicit base is used in the conversion of the bounds, we
14637 -- have to freeze it now. This is similar to what is done for numeric
14638 -- types, and it equally suspicious, but otherwise a non-static bound
14639 -- will have a reference to an unfrozen type, which is rejected by Gigi
14640 -- (???). This requires specific care for definition of stream
14641 -- attributes. For details, see comments at the end of
14642 -- Build_Derived_Numeric_Type.
14644 Freeze_Before (N, Implicit_Base);
14645 end Derived_Standard_Character;
14647 ------------------------------
14648 -- Derived_Type_Declaration --
14649 ------------------------------
14651 procedure Derived_Type_Declaration
14654 Is_Completion : Boolean)
14656 Parent_Type : Entity_Id;
14658 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
14659 -- Check whether the parent type is a generic formal, or derives
14660 -- directly or indirectly from one.
14662 ------------------------
14663 -- Comes_From_Generic --
14664 ------------------------
14666 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
14668 if Is_Generic_Type (Typ) then
14671 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
14674 elsif Is_Private_Type (Typ)
14675 and then Present (Full_View (Typ))
14676 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
14680 elsif Is_Generic_Actual_Type (Typ) then
14686 end Comes_From_Generic;
14690 Def : constant Node_Id := Type_Definition (N);
14691 Iface_Def : Node_Id;
14692 Indic : constant Node_Id := Subtype_Indication (Def);
14693 Extension : constant Node_Id := Record_Extension_Part (Def);
14694 Parent_Node : Node_Id;
14697 -- Start of processing for Derived_Type_Declaration
14700 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
14702 -- Ada 2005 (AI-251): In case of interface derivation check that the
14703 -- parent is also an interface.
14705 if Interface_Present (Def) then
14706 Check_SPARK_Restriction ("interface is not allowed", Def);
14708 if not Is_Interface (Parent_Type) then
14709 Diagnose_Interface (Indic, Parent_Type);
14712 Parent_Node := Parent (Base_Type (Parent_Type));
14713 Iface_Def := Type_Definition (Parent_Node);
14715 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
14716 -- other limited interfaces.
14718 if Limited_Present (Def) then
14719 if Limited_Present (Iface_Def) then
14722 elsif Protected_Present (Iface_Def) then
14724 ("descendant of& must be declared"
14725 & " as a protected interface",
14728 elsif Synchronized_Present (Iface_Def) then
14730 ("descendant of& must be declared"
14731 & " as a synchronized interface",
14734 elsif Task_Present (Iface_Def) then
14736 ("descendant of& must be declared as a task interface",
14741 ("(Ada 2005) limited interface cannot "
14742 & "inherit from non-limited interface", Indic);
14745 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
14746 -- from non-limited or limited interfaces.
14748 elsif not Protected_Present (Def)
14749 and then not Synchronized_Present (Def)
14750 and then not Task_Present (Def)
14752 if Limited_Present (Iface_Def) then
14755 elsif Protected_Present (Iface_Def) then
14757 ("descendant of& must be declared"
14758 & " as a protected interface",
14761 elsif Synchronized_Present (Iface_Def) then
14763 ("descendant of& must be declared"
14764 & " as a synchronized interface",
14767 elsif Task_Present (Iface_Def) then
14769 ("descendant of& must be declared as a task interface",
14778 if Is_Tagged_Type (Parent_Type)
14779 and then Is_Concurrent_Type (Parent_Type)
14780 and then not Is_Interface (Parent_Type)
14783 ("parent type of a record extension cannot be "
14784 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
14785 Set_Etype (T, Any_Type);
14789 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
14792 if Is_Tagged_Type (Parent_Type)
14793 and then Is_Non_Empty_List (Interface_List (Def))
14800 Intf := First (Interface_List (Def));
14801 while Present (Intf) loop
14802 T := Find_Type_Of_Subtype_Indic (Intf);
14804 if not Is_Interface (T) then
14805 Diagnose_Interface (Intf, T);
14807 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
14808 -- a limited type from having a nonlimited progenitor.
14810 elsif (Limited_Present (Def)
14811 or else (not Is_Interface (Parent_Type)
14812 and then Is_Limited_Type (Parent_Type)))
14813 and then not Is_Limited_Interface (T)
14816 ("progenitor interface& of limited type must be limited",
14825 if Parent_Type = Any_Type
14826 or else Etype (Parent_Type) = Any_Type
14827 or else (Is_Class_Wide_Type (Parent_Type)
14828 and then Etype (Parent_Type) = T)
14830 -- If Parent_Type is undefined or illegal, make new type into a
14831 -- subtype of Any_Type, and set a few attributes to prevent cascaded
14832 -- errors. If this is a self-definition, emit error now.
14835 or else T = Etype (Parent_Type)
14837 Error_Msg_N ("type cannot be used in its own definition", Indic);
14840 Set_Ekind (T, Ekind (Parent_Type));
14841 Set_Etype (T, Any_Type);
14842 Set_Scalar_Range (T, Scalar_Range (Any_Type));
14844 if Is_Tagged_Type (T)
14845 and then Is_Record_Type (T)
14847 Set_Direct_Primitive_Operations (T, New_Elmt_List);
14853 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
14854 -- an interface is special because the list of interfaces in the full
14855 -- view can be given in any order. For example:
14857 -- type A is interface;
14858 -- type B is interface and A;
14859 -- type D is new B with private;
14861 -- type D is new A and B with null record; -- 1 --
14863 -- In this case we perform the following transformation of -1-:
14865 -- type D is new B and A with null record;
14867 -- If the parent of the full-view covers the parent of the partial-view
14868 -- we have two possible cases:
14870 -- 1) They have the same parent
14871 -- 2) The parent of the full-view implements some further interfaces
14873 -- In both cases we do not need to perform the transformation. In the
14874 -- first case the source program is correct and the transformation is
14875 -- not needed; in the second case the source program does not fulfill
14876 -- the no-hidden interfaces rule (AI-396) and the error will be reported
14879 -- This transformation not only simplifies the rest of the analysis of
14880 -- this type declaration but also simplifies the correct generation of
14881 -- the object layout to the expander.
14883 if In_Private_Part (Current_Scope)
14884 and then Is_Interface (Parent_Type)
14888 Partial_View : Entity_Id;
14889 Partial_View_Parent : Entity_Id;
14890 New_Iface : Node_Id;
14893 -- Look for the associated private type declaration
14895 Partial_View := First_Entity (Current_Scope);
14897 exit when No (Partial_View)
14898 or else (Has_Private_Declaration (Partial_View)
14899 and then Full_View (Partial_View) = T);
14901 Next_Entity (Partial_View);
14904 -- If the partial view was not found then the source code has
14905 -- errors and the transformation is not needed.
14907 if Present (Partial_View) then
14908 Partial_View_Parent := Etype (Partial_View);
14910 -- If the parent of the full-view covers the parent of the
14911 -- partial-view we have nothing else to do.
14913 if Interface_Present_In_Ancestor
14914 (Parent_Type, Partial_View_Parent)
14918 -- Traverse the list of interfaces of the full-view to look
14919 -- for the parent of the partial-view and perform the tree
14923 Iface := First (Interface_List (Def));
14924 while Present (Iface) loop
14925 if Etype (Iface) = Etype (Partial_View) then
14926 Rewrite (Subtype_Indication (Def),
14927 New_Copy (Subtype_Indication
14928 (Parent (Partial_View))));
14931 Make_Identifier (Sloc (N), Chars (Parent_Type));
14932 Append (New_Iface, Interface_List (Def));
14934 -- Analyze the transformed code
14936 Derived_Type_Declaration (T, N, Is_Completion);
14947 -- Only composite types other than array types are allowed to have
14948 -- discriminants. In SPARK, no types are allowed to have discriminants.
14950 if Present (Discriminant_Specifications (N)) then
14951 if (Is_Elementary_Type (Parent_Type)
14952 or else Is_Array_Type (Parent_Type))
14953 and then not Error_Posted (N)
14956 ("elementary or array type cannot have discriminants",
14957 Defining_Identifier (First (Discriminant_Specifications (N))));
14958 Set_Has_Discriminants (T, False);
14960 Check_SPARK_Restriction ("discriminant type is not allowed", N);
14964 -- In Ada 83, a derived type defined in a package specification cannot
14965 -- be used for further derivation until the end of its visible part.
14966 -- Note that derivation in the private part of the package is allowed.
14968 if Ada_Version = Ada_83
14969 and then Is_Derived_Type (Parent_Type)
14970 and then In_Visible_Part (Scope (Parent_Type))
14972 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
14974 ("(Ada 83): premature use of type for derivation", Indic);
14978 -- Check for early use of incomplete or private type
14980 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
14981 Error_Msg_N ("premature derivation of incomplete type", Indic);
14984 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
14985 and then not Comes_From_Generic (Parent_Type))
14986 or else Has_Private_Component (Parent_Type)
14988 -- The ancestor type of a formal type can be incomplete, in which
14989 -- case only the operations of the partial view are available in the
14990 -- generic. Subsequent checks may be required when the full view is
14991 -- analyzed to verify that a derivation from a tagged type has an
14994 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
14997 elsif No (Underlying_Type (Parent_Type))
14998 or else Has_Private_Component (Parent_Type)
15001 ("premature derivation of derived or private type", Indic);
15003 -- Flag the type itself as being in error, this prevents some
15004 -- nasty problems with subsequent uses of the malformed type.
15006 Set_Error_Posted (T);
15008 -- Check that within the immediate scope of an untagged partial
15009 -- view it's illegal to derive from the partial view if the
15010 -- full view is tagged. (7.3(7))
15012 -- We verify that the Parent_Type is a partial view by checking
15013 -- that it is not a Full_Type_Declaration (i.e. a private type or
15014 -- private extension declaration), to distinguish a partial view
15015 -- from a derivation from a private type which also appears as
15016 -- E_Private_Type. If the parent base type is not declared in an
15017 -- enclosing scope there is no need to check.
15019 elsif Present (Full_View (Parent_Type))
15020 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
15021 and then not Is_Tagged_Type (Parent_Type)
15022 and then Is_Tagged_Type (Full_View (Parent_Type))
15023 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
15026 ("premature derivation from type with tagged full view",
15031 -- Check that form of derivation is appropriate
15033 Taggd := Is_Tagged_Type (Parent_Type);
15035 -- Perhaps the parent type should be changed to the class-wide type's
15036 -- specific type in this case to prevent cascading errors ???
15038 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
15039 Error_Msg_N ("parent type must not be a class-wide type", Indic);
15043 if Present (Extension) and then not Taggd then
15045 ("type derived from untagged type cannot have extension", Indic);
15047 elsif No (Extension) and then Taggd then
15049 -- If this declaration is within a private part (or body) of a
15050 -- generic instantiation then the derivation is allowed (the parent
15051 -- type can only appear tagged in this case if it's a generic actual
15052 -- type, since it would otherwise have been rejected in the analysis
15053 -- of the generic template).
15055 if not Is_Generic_Actual_Type (Parent_Type)
15056 or else In_Visible_Part (Scope (Parent_Type))
15058 if Is_Class_Wide_Type (Parent_Type) then
15060 ("parent type must not be a class-wide type", Indic);
15062 -- Use specific type to prevent cascaded errors.
15064 Parent_Type := Etype (Parent_Type);
15068 ("type derived from tagged type must have extension", Indic);
15073 -- AI-443: Synchronized formal derived types require a private
15074 -- extension. There is no point in checking the ancestor type or
15075 -- the progenitors since the construct is wrong to begin with.
15077 if Ada_Version >= Ada_2005
15078 and then Is_Generic_Type (T)
15079 and then Present (Original_Node (N))
15082 Decl : constant Node_Id := Original_Node (N);
15085 if Nkind (Decl) = N_Formal_Type_Declaration
15086 and then Nkind (Formal_Type_Definition (Decl)) =
15087 N_Formal_Derived_Type_Definition
15088 and then Synchronized_Present (Formal_Type_Definition (Decl))
15089 and then No (Extension)
15091 -- Avoid emitting a duplicate error message
15093 and then not Error_Posted (Indic)
15096 ("synchronized derived type must have extension", N);
15101 if Null_Exclusion_Present (Def)
15102 and then not Is_Access_Type (Parent_Type)
15104 Error_Msg_N ("null exclusion can only apply to an access type", N);
15107 -- Avoid deriving parent primitives of underlying record views
15109 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
15110 Derive_Subps => not Is_Underlying_Record_View (T));
15112 -- AI-419: The parent type of an explicitly limited derived type must
15113 -- be a limited type or a limited interface.
15115 if Limited_Present (Def) then
15116 Set_Is_Limited_Record (T);
15118 if Is_Interface (T) then
15119 Set_Is_Limited_Interface (T);
15122 if not Is_Limited_Type (Parent_Type)
15124 (not Is_Interface (Parent_Type)
15125 or else not Is_Limited_Interface (Parent_Type))
15127 -- AI05-0096: a derivation in the private part of an instance is
15128 -- legal if the generic formal is untagged limited, and the actual
15131 if Is_Generic_Actual_Type (Parent_Type)
15132 and then In_Private_Part (Current_Scope)
15135 (Generic_Parent_Type (Parent (Parent_Type)))
15141 ("parent type& of limited type must be limited",
15147 -- In SPARK, there are no derived type definitions other than type
15148 -- extensions of tagged record types.
15150 if No (Extension) then
15151 Check_SPARK_Restriction
15152 ("derived type is not allowed", Original_Node (N));
15154 end Derived_Type_Declaration;
15156 ------------------------
15157 -- Diagnose_Interface --
15158 ------------------------
15160 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
15162 if not Is_Interface (E)
15163 and then E /= Any_Type
15165 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
15167 end Diagnose_Interface;
15169 ----------------------------------
15170 -- Enumeration_Type_Declaration --
15171 ----------------------------------
15173 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
15180 -- Create identifier node representing lower bound
15182 B_Node := New_Node (N_Identifier, Sloc (Def));
15183 L := First (Literals (Def));
15184 Set_Chars (B_Node, Chars (L));
15185 Set_Entity (B_Node, L);
15186 Set_Etype (B_Node, T);
15187 Set_Is_Static_Expression (B_Node, True);
15189 R_Node := New_Node (N_Range, Sloc (Def));
15190 Set_Low_Bound (R_Node, B_Node);
15192 Set_Ekind (T, E_Enumeration_Type);
15193 Set_First_Literal (T, L);
15195 Set_Is_Constrained (T);
15199 -- Loop through literals of enumeration type setting pos and rep values
15200 -- except that if the Ekind is already set, then it means the literal
15201 -- was already constructed (case of a derived type declaration and we
15202 -- should not disturb the Pos and Rep values.
15204 while Present (L) loop
15205 if Ekind (L) /= E_Enumeration_Literal then
15206 Set_Ekind (L, E_Enumeration_Literal);
15207 Set_Enumeration_Pos (L, Ev);
15208 Set_Enumeration_Rep (L, Ev);
15209 Set_Is_Known_Valid (L, True);
15213 New_Overloaded_Entity (L);
15214 Generate_Definition (L);
15215 Set_Convention (L, Convention_Intrinsic);
15217 -- Case of character literal
15219 if Nkind (L) = N_Defining_Character_Literal then
15220 Set_Is_Character_Type (T, True);
15222 -- Check violation of No_Wide_Characters
15224 if Restriction_Check_Required (No_Wide_Characters) then
15225 Get_Name_String (Chars (L));
15227 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
15228 Check_Restriction (No_Wide_Characters, L);
15237 -- Now create a node representing upper bound
15239 B_Node := New_Node (N_Identifier, Sloc (Def));
15240 Set_Chars (B_Node, Chars (Last (Literals (Def))));
15241 Set_Entity (B_Node, Last (Literals (Def)));
15242 Set_Etype (B_Node, T);
15243 Set_Is_Static_Expression (B_Node, True);
15245 Set_High_Bound (R_Node, B_Node);
15247 -- Initialize various fields of the type. Some of this information
15248 -- may be overwritten later through rep.clauses.
15250 Set_Scalar_Range (T, R_Node);
15251 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
15252 Set_Enum_Esize (T);
15253 Set_Enum_Pos_To_Rep (T, Empty);
15255 -- Set Discard_Names if configuration pragma set, or if there is
15256 -- a parameterless pragma in the current declarative region
15258 if Global_Discard_Names or else Discard_Names (Scope (T)) then
15259 Set_Discard_Names (T);
15262 -- Process end label if there is one
15264 if Present (Def) then
15265 Process_End_Label (Def, 'e', T);
15267 end Enumeration_Type_Declaration;
15269 ---------------------------------
15270 -- Expand_To_Stored_Constraint --
15271 ---------------------------------
15273 function Expand_To_Stored_Constraint
15275 Constraint : Elist_Id) return Elist_Id
15277 Explicitly_Discriminated_Type : Entity_Id;
15278 Expansion : Elist_Id;
15279 Discriminant : Entity_Id;
15281 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
15282 -- Find the nearest type that actually specifies discriminants
15284 ---------------------------------
15285 -- Type_With_Explicit_Discrims --
15286 ---------------------------------
15288 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
15289 Typ : constant E := Base_Type (Id);
15292 if Ekind (Typ) in Incomplete_Or_Private_Kind then
15293 if Present (Full_View (Typ)) then
15294 return Type_With_Explicit_Discrims (Full_View (Typ));
15298 if Has_Discriminants (Typ) then
15303 if Etype (Typ) = Typ then
15305 elsif Has_Discriminants (Typ) then
15308 return Type_With_Explicit_Discrims (Etype (Typ));
15311 end Type_With_Explicit_Discrims;
15313 -- Start of processing for Expand_To_Stored_Constraint
15317 or else Is_Empty_Elmt_List (Constraint)
15322 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
15324 if No (Explicitly_Discriminated_Type) then
15328 Expansion := New_Elmt_List;
15331 First_Stored_Discriminant (Explicitly_Discriminated_Type);
15332 while Present (Discriminant) loop
15334 Get_Discriminant_Value (
15335 Discriminant, Explicitly_Discriminated_Type, Constraint),
15337 Next_Stored_Discriminant (Discriminant);
15341 end Expand_To_Stored_Constraint;
15343 ---------------------------
15344 -- Find_Hidden_Interface --
15345 ---------------------------
15347 function Find_Hidden_Interface
15349 Dest : Elist_Id) return Entity_Id
15352 Iface_Elmt : Elmt_Id;
15355 if Present (Src) and then Present (Dest) then
15356 Iface_Elmt := First_Elmt (Src);
15357 while Present (Iface_Elmt) loop
15358 Iface := Node (Iface_Elmt);
15360 if Is_Interface (Iface)
15361 and then not Contain_Interface (Iface, Dest)
15366 Next_Elmt (Iface_Elmt);
15371 end Find_Hidden_Interface;
15373 --------------------
15374 -- Find_Type_Name --
15375 --------------------
15377 function Find_Type_Name (N : Node_Id) return Entity_Id is
15378 Id : constant Entity_Id := Defining_Identifier (N);
15380 New_Id : Entity_Id;
15381 Prev_Par : Node_Id;
15383 procedure Check_Duplicate_Aspects;
15384 -- Check that aspects specified in a completion have not been specified
15385 -- already in the partial view. Type_Invariant and others can be
15386 -- specified on either view but never on both.
15388 procedure Tag_Mismatch;
15389 -- Diagnose a tagged partial view whose full view is untagged.
15390 -- We post the message on the full view, with a reference to
15391 -- the previous partial view. The partial view can be private
15392 -- or incomplete, and these are handled in a different manner,
15393 -- so we determine the position of the error message from the
15394 -- respective slocs of both.
15396 -----------------------------
15397 -- Check_Duplicate_Aspects --
15398 -----------------------------
15399 procedure Check_Duplicate_Aspects is
15400 Prev_Aspects : constant List_Id := Aspect_Specifications (Prev_Par);
15401 Full_Aspects : constant List_Id := Aspect_Specifications (N);
15402 F_Spec, P_Spec : Node_Id;
15405 if Present (Prev_Aspects) and then Present (Full_Aspects) then
15406 F_Spec := First (Full_Aspects);
15407 while Present (F_Spec) loop
15408 P_Spec := First (Prev_Aspects);
15409 while Present (P_Spec) loop
15411 Chars (Identifier (P_Spec)) = Chars (Identifier (F_Spec))
15414 ("aspect already specified in private declaration",
15426 end Check_Duplicate_Aspects;
15432 procedure Tag_Mismatch is
15434 if Sloc (Prev) < Sloc (Id) then
15435 if Ada_Version >= Ada_2012
15436 and then Nkind (N) = N_Private_Type_Declaration
15439 ("declaration of private } must be a tagged type ", Id, Prev);
15442 ("full declaration of } must be a tagged type ", Id, Prev);
15446 if Ada_Version >= Ada_2012
15447 and then Nkind (N) = N_Private_Type_Declaration
15450 ("declaration of private } must be a tagged type ", Prev, Id);
15453 ("full declaration of } must be a tagged type ", Prev, Id);
15458 -- Start of processing for Find_Type_Name
15461 -- Find incomplete declaration, if one was given
15463 Prev := Current_Entity_In_Scope (Id);
15465 -- New type declaration
15471 -- Previous declaration exists
15474 Prev_Par := Parent (Prev);
15476 -- Error if not incomplete/private case except if previous
15477 -- declaration is implicit, etc. Enter_Name will emit error if
15480 if not Is_Incomplete_Or_Private_Type (Prev) then
15484 -- Check invalid completion of private or incomplete type
15486 elsif not Nkind_In (N, N_Full_Type_Declaration,
15487 N_Task_Type_Declaration,
15488 N_Protected_Type_Declaration)
15490 (Ada_Version < Ada_2012
15491 or else not Is_Incomplete_Type (Prev)
15492 or else not Nkind_In (N, N_Private_Type_Declaration,
15493 N_Private_Extension_Declaration))
15495 -- Completion must be a full type declarations (RM 7.3(4))
15497 Error_Msg_Sloc := Sloc (Prev);
15498 Error_Msg_NE ("invalid completion of }", Id, Prev);
15500 -- Set scope of Id to avoid cascaded errors. Entity is never
15501 -- examined again, except when saving globals in generics.
15503 Set_Scope (Id, Current_Scope);
15506 -- If this is a repeated incomplete declaration, no further
15507 -- checks are possible.
15509 if Nkind (N) = N_Incomplete_Type_Declaration then
15513 -- Case of full declaration of incomplete type
15515 elsif Ekind (Prev) = E_Incomplete_Type
15516 and then (Ada_Version < Ada_2012
15517 or else No (Full_View (Prev))
15518 or else not Is_Private_Type (Full_View (Prev)))
15520 -- Indicate that the incomplete declaration has a matching full
15521 -- declaration. The defining occurrence of the incomplete
15522 -- declaration remains the visible one, and the procedure
15523 -- Get_Full_View dereferences it whenever the type is used.
15525 if Present (Full_View (Prev)) then
15526 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
15529 Set_Full_View (Prev, Id);
15530 Append_Entity (Id, Current_Scope);
15531 Set_Is_Public (Id, Is_Public (Prev));
15532 Set_Is_Internal (Id);
15535 -- If the incomplete view is tagged, a class_wide type has been
15536 -- created already. Use it for the private type as well, in order
15537 -- to prevent multiple incompatible class-wide types that may be
15538 -- created for self-referential anonymous access components.
15540 if Is_Tagged_Type (Prev)
15541 and then Present (Class_Wide_Type (Prev))
15543 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
15544 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
15546 -- If the incomplete type is completed by a private declaration
15547 -- the class-wide type remains associated with the incomplete
15548 -- type, to prevent order-of-elaboration issues in gigi, else
15549 -- we associate the class-wide type with the known full view.
15551 if Nkind (N) /= N_Private_Type_Declaration then
15552 Set_Etype (Class_Wide_Type (Id), Id);
15556 -- Case of full declaration of private type
15559 -- If the private type was a completion of an incomplete type then
15560 -- update Prev to reference the private type
15562 if Ada_Version >= Ada_2012
15563 and then Ekind (Prev) = E_Incomplete_Type
15564 and then Present (Full_View (Prev))
15565 and then Is_Private_Type (Full_View (Prev))
15567 Prev := Full_View (Prev);
15568 Prev_Par := Parent (Prev);
15571 if Nkind (N) = N_Full_Type_Declaration
15573 (Type_Definition (N), N_Record_Definition,
15574 N_Derived_Type_Definition)
15575 and then Interface_Present (Type_Definition (N))
15578 ("completion of private type cannot be an interface", N);
15581 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
15582 if Etype (Prev) /= Prev then
15584 -- Prev is a private subtype or a derived type, and needs
15587 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
15590 elsif Ekind (Prev) = E_Private_Type
15591 and then Nkind_In (N, N_Task_Type_Declaration,
15592 N_Protected_Type_Declaration)
15595 ("completion of nonlimited type cannot be limited", N);
15597 elsif Ekind (Prev) = E_Record_Type_With_Private
15598 and then Nkind_In (N, N_Task_Type_Declaration,
15599 N_Protected_Type_Declaration)
15601 if not Is_Limited_Record (Prev) then
15603 ("completion of nonlimited type cannot be limited", N);
15605 elsif No (Interface_List (N)) then
15607 ("completion of tagged private type must be tagged",
15612 -- Ada 2005 (AI-251): Private extension declaration of a task
15613 -- type or a protected type. This case arises when covering
15614 -- interface types.
15616 elsif Nkind_In (N, N_Task_Type_Declaration,
15617 N_Protected_Type_Declaration)
15621 elsif Nkind (N) /= N_Full_Type_Declaration
15622 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
15625 ("full view of private extension must be an extension", N);
15627 elsif not (Abstract_Present (Parent (Prev)))
15628 and then Abstract_Present (Type_Definition (N))
15631 ("full view of non-abstract extension cannot be abstract", N);
15634 if not In_Private_Part (Current_Scope) then
15636 ("declaration of full view must appear in private part", N);
15639 if Ada_Version >= Ada_2012 then
15640 Check_Duplicate_Aspects;
15643 Copy_And_Swap (Prev, Id);
15644 Set_Has_Private_Declaration (Prev);
15645 Set_Has_Private_Declaration (Id);
15647 -- Preserve aspect and iterator flags that may have been set on
15648 -- the partial view.
15650 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
15651 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
15653 -- If no error, propagate freeze_node from private to full view.
15654 -- It may have been generated for an early operational item.
15656 if Present (Freeze_Node (Id))
15657 and then Serious_Errors_Detected = 0
15658 and then No (Full_View (Id))
15660 Set_Freeze_Node (Prev, Freeze_Node (Id));
15661 Set_Freeze_Node (Id, Empty);
15662 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
15665 Set_Full_View (Id, Prev);
15669 -- Verify that full declaration conforms to partial one
15671 if Is_Incomplete_Or_Private_Type (Prev)
15672 and then Present (Discriminant_Specifications (Prev_Par))
15674 if Present (Discriminant_Specifications (N)) then
15675 if Ekind (Prev) = E_Incomplete_Type then
15676 Check_Discriminant_Conformance (N, Prev, Prev);
15678 Check_Discriminant_Conformance (N, Prev, Id);
15683 ("missing discriminants in full type declaration", N);
15685 -- To avoid cascaded errors on subsequent use, share the
15686 -- discriminants of the partial view.
15688 Set_Discriminant_Specifications (N,
15689 Discriminant_Specifications (Prev_Par));
15693 -- A prior untagged partial view can have an associated class-wide
15694 -- type due to use of the class attribute, and in this case the full
15695 -- type must also be tagged. This Ada 95 usage is deprecated in favor
15696 -- of incomplete tagged declarations, but we check for it.
15699 and then (Is_Tagged_Type (Prev)
15700 or else Present (Class_Wide_Type (Prev)))
15702 -- Ada 2012 (AI05-0162): A private type may be the completion of
15703 -- an incomplete type.
15705 if Ada_Version >= Ada_2012
15706 and then Is_Incomplete_Type (Prev)
15707 and then Nkind_In (N, N_Private_Type_Declaration,
15708 N_Private_Extension_Declaration)
15710 -- No need to check private extensions since they are tagged
15712 if Nkind (N) = N_Private_Type_Declaration
15713 and then not Tagged_Present (N)
15718 -- The full declaration is either a tagged type (including
15719 -- a synchronized type that implements interfaces) or a
15720 -- type extension, otherwise this is an error.
15722 elsif Nkind_In (N, N_Task_Type_Declaration,
15723 N_Protected_Type_Declaration)
15725 if No (Interface_List (N))
15726 and then not Error_Posted (N)
15731 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
15733 -- Indicate that the previous declaration (tagged incomplete
15734 -- or private declaration) requires the same on the full one.
15736 if not Tagged_Present (Type_Definition (N)) then
15738 Set_Is_Tagged_Type (Id);
15741 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
15742 if No (Record_Extension_Part (Type_Definition (N))) then
15744 ("full declaration of } must be a record extension",
15747 -- Set some attributes to produce a usable full view
15749 Set_Is_Tagged_Type (Id);
15758 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
15759 and then Present (Premature_Use (Parent (Prev)))
15761 Error_Msg_Sloc := Sloc (N);
15763 ("\full declaration #", Premature_Use (Parent (Prev)));
15768 end Find_Type_Name;
15770 -------------------------
15771 -- Find_Type_Of_Object --
15772 -------------------------
15774 function Find_Type_Of_Object
15775 (Obj_Def : Node_Id;
15776 Related_Nod : Node_Id) return Entity_Id
15778 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
15779 P : Node_Id := Parent (Obj_Def);
15784 -- If the parent is a component_definition node we climb to the
15785 -- component_declaration node
15787 if Nkind (P) = N_Component_Definition then
15791 -- Case of an anonymous array subtype
15793 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
15794 N_Unconstrained_Array_Definition)
15797 Array_Type_Declaration (T, Obj_Def);
15799 -- Create an explicit subtype whenever possible
15801 elsif Nkind (P) /= N_Component_Declaration
15802 and then Def_Kind = N_Subtype_Indication
15804 -- Base name of subtype on object name, which will be unique in
15805 -- the current scope.
15807 -- If this is a duplicate declaration, return base type, to avoid
15808 -- generating duplicate anonymous types.
15810 if Error_Posted (P) then
15811 Analyze (Subtype_Mark (Obj_Def));
15812 return Entity (Subtype_Mark (Obj_Def));
15817 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
15819 T := Make_Defining_Identifier (Sloc (P), Nam);
15821 Insert_Action (Obj_Def,
15822 Make_Subtype_Declaration (Sloc (P),
15823 Defining_Identifier => T,
15824 Subtype_Indication => Relocate_Node (Obj_Def)));
15826 -- This subtype may need freezing, and this will not be done
15827 -- automatically if the object declaration is not in declarative
15828 -- part. Since this is an object declaration, the type cannot always
15829 -- be frozen here. Deferred constants do not freeze their type
15830 -- (which often enough will be private).
15832 if Nkind (P) = N_Object_Declaration
15833 and then Constant_Present (P)
15834 and then No (Expression (P))
15838 -- Here we freeze the base type of object type to catch premature use
15839 -- of discriminated private type without a full view.
15842 Insert_Actions (Obj_Def, Freeze_Entity (Base_Type (T), P));
15845 -- Ada 2005 AI-406: the object definition in an object declaration
15846 -- can be an access definition.
15848 elsif Def_Kind = N_Access_Definition then
15849 T := Access_Definition (Related_Nod, Obj_Def);
15851 Set_Is_Local_Anonymous_Access
15853 V => (Ada_Version < Ada_2012)
15854 or else (Nkind (P) /= N_Object_Declaration)
15855 or else Is_Library_Level_Entity (Defining_Identifier (P)));
15857 -- Otherwise, the object definition is just a subtype_mark
15860 T := Process_Subtype (Obj_Def, Related_Nod);
15862 -- If expansion is disabled an object definition that is an aggregate
15863 -- will not get expanded and may lead to scoping problems in the back
15864 -- end, if the object is referenced in an inner scope. In that case
15865 -- create an itype reference for the object definition now. This
15866 -- may be redundant in some cases, but harmless.
15869 and then Nkind (Related_Nod) = N_Object_Declaration
15872 Build_Itype_Reference (T, Related_Nod);
15877 end Find_Type_Of_Object;
15879 --------------------------------
15880 -- Find_Type_Of_Subtype_Indic --
15881 --------------------------------
15883 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
15887 -- Case of subtype mark with a constraint
15889 if Nkind (S) = N_Subtype_Indication then
15890 Find_Type (Subtype_Mark (S));
15891 Typ := Entity (Subtype_Mark (S));
15894 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
15897 ("incorrect constraint for this kind of type", Constraint (S));
15898 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
15901 -- Otherwise we have a subtype mark without a constraint
15903 elsif Error_Posted (S) then
15904 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
15912 -- Check No_Wide_Characters restriction
15914 Check_Wide_Character_Restriction (Typ, S);
15917 end Find_Type_Of_Subtype_Indic;
15919 -------------------------------------
15920 -- Floating_Point_Type_Declaration --
15921 -------------------------------------
15923 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
15924 Digs : constant Node_Id := Digits_Expression (Def);
15925 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
15927 Base_Typ : Entity_Id;
15928 Implicit_Base : Entity_Id;
15931 function Can_Derive_From (E : Entity_Id) return Boolean;
15932 -- Find if given digits value, and possibly a specified range, allows
15933 -- derivation from specified type
15935 function Find_Base_Type return Entity_Id;
15936 -- Find a predefined base type that Def can derive from, or generate
15937 -- an error and substitute Long_Long_Float if none exists.
15939 ---------------------
15940 -- Can_Derive_From --
15941 ---------------------
15943 function Can_Derive_From (E : Entity_Id) return Boolean is
15944 Spec : constant Entity_Id := Real_Range_Specification (Def);
15947 -- Check specified "digits" constraint
15949 if Digs_Val > Digits_Value (E) then
15953 -- Avoid types not matching pragma Float_Representation, if present
15955 if (Opt.Float_Format = 'I' and then Float_Rep (E) /= IEEE_Binary)
15957 (Opt.Float_Format = 'V' and then Float_Rep (E) /= VAX_Native)
15962 -- Check for matching range, if specified
15964 if Present (Spec) then
15965 if Expr_Value_R (Type_Low_Bound (E)) >
15966 Expr_Value_R (Low_Bound (Spec))
15971 if Expr_Value_R (Type_High_Bound (E)) <
15972 Expr_Value_R (High_Bound (Spec))
15979 end Can_Derive_From;
15981 --------------------
15982 -- Find_Base_Type --
15983 --------------------
15985 function Find_Base_Type return Entity_Id is
15986 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
15989 -- Iterate over the predefined types in order, returning the first
15990 -- one that Def can derive from.
15992 while Present (Choice) loop
15993 if Can_Derive_From (Node (Choice)) then
15994 return Node (Choice);
15997 Next_Elmt (Choice);
16000 -- If we can't derive from any existing type, use Long_Long_Float
16001 -- and give appropriate message explaining the problem.
16003 if Digs_Val > Max_Digs_Val then
16004 -- It might be the case that there is a type with the requested
16005 -- range, just not the combination of digits and range.
16008 ("no predefined type has requested range and precision",
16009 Real_Range_Specification (Def));
16013 ("range too large for any predefined type",
16014 Real_Range_Specification (Def));
16017 return Standard_Long_Long_Float;
16018 end Find_Base_Type;
16020 -- Start of processing for Floating_Point_Type_Declaration
16023 Check_Restriction (No_Floating_Point, Def);
16025 -- Create an implicit base type
16028 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
16030 -- Analyze and verify digits value
16032 Analyze_And_Resolve (Digs, Any_Integer);
16033 Check_Digits_Expression (Digs);
16034 Digs_Val := Expr_Value (Digs);
16036 -- Process possible range spec and find correct type to derive from
16038 Process_Real_Range_Specification (Def);
16040 -- Check that requested number of digits is not too high.
16042 if Digs_Val > Max_Digs_Val then
16043 -- The check for Max_Base_Digits may be somewhat expensive, as it
16044 -- requires reading System, so only do it when necessary.
16047 Max_Base_Digits : constant Uint :=
16050 (Parent (RTE (RE_Max_Base_Digits))));
16053 if Digs_Val > Max_Base_Digits then
16054 Error_Msg_Uint_1 := Max_Base_Digits;
16055 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
16057 elsif No (Real_Range_Specification (Def)) then
16058 Error_Msg_Uint_1 := Max_Digs_Val;
16059 Error_Msg_N ("types with more than ^ digits need range spec "
16060 & "(RM 3.5.7(6))", Digs);
16065 -- Find a suitable type to derive from or complain and use a substitute
16067 Base_Typ := Find_Base_Type;
16069 -- If there are bounds given in the declaration use them as the bounds
16070 -- of the type, otherwise use the bounds of the predefined base type
16071 -- that was chosen based on the Digits value.
16073 if Present (Real_Range_Specification (Def)) then
16074 Set_Scalar_Range (T, Real_Range_Specification (Def));
16075 Set_Is_Constrained (T);
16077 -- The bounds of this range must be converted to machine numbers
16078 -- in accordance with RM 4.9(38).
16080 Bound := Type_Low_Bound (T);
16082 if Nkind (Bound) = N_Real_Literal then
16084 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
16085 Set_Is_Machine_Number (Bound);
16088 Bound := Type_High_Bound (T);
16090 if Nkind (Bound) = N_Real_Literal then
16092 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
16093 Set_Is_Machine_Number (Bound);
16097 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
16100 -- Complete definition of implicit base and declared first subtype
16102 Set_Etype (Implicit_Base, Base_Typ);
16104 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
16105 Set_Size_Info (Implicit_Base, (Base_Typ));
16106 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
16107 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
16108 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
16109 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
16111 Set_Ekind (T, E_Floating_Point_Subtype);
16112 Set_Etype (T, Implicit_Base);
16114 Set_Size_Info (T, (Implicit_Base));
16115 Set_RM_Size (T, RM_Size (Implicit_Base));
16116 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
16117 Set_Digits_Value (T, Digs_Val);
16118 end Floating_Point_Type_Declaration;
16120 ----------------------------
16121 -- Get_Discriminant_Value --
16122 ----------------------------
16124 -- This is the situation:
16126 -- There is a non-derived type
16128 -- type T0 (Dx, Dy, Dz...)
16130 -- There are zero or more levels of derivation, with each derivation
16131 -- either purely inheriting the discriminants, or defining its own.
16133 -- type Ti is new Ti-1
16135 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
16137 -- subtype Ti is ...
16139 -- The subtype issue is avoided by the use of Original_Record_Component,
16140 -- and the fact that derived subtypes also derive the constraints.
16142 -- This chain leads back from
16144 -- Typ_For_Constraint
16146 -- Typ_For_Constraint has discriminants, and the value for each
16147 -- discriminant is given by its corresponding Elmt of Constraints.
16149 -- Discriminant is some discriminant in this hierarchy
16151 -- We need to return its value
16153 -- We do this by recursively searching each level, and looking for
16154 -- Discriminant. Once we get to the bottom, we start backing up
16155 -- returning the value for it which may in turn be a discriminant
16156 -- further up, so on the backup we continue the substitution.
16158 function Get_Discriminant_Value
16159 (Discriminant : Entity_Id;
16160 Typ_For_Constraint : Entity_Id;
16161 Constraint : Elist_Id) return Node_Id
16163 function Root_Corresponding_Discriminant
16164 (Discr : Entity_Id) return Entity_Id;
16165 -- Given a discriminant, traverse the chain of inherited discriminants
16166 -- and return the topmost discriminant.
16168 function Search_Derivation_Levels
16170 Discrim_Values : Elist_Id;
16171 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
16172 -- This is the routine that performs the recursive search of levels
16173 -- as described above.
16175 -------------------------------------
16176 -- Root_Corresponding_Discriminant --
16177 -------------------------------------
16179 function Root_Corresponding_Discriminant
16180 (Discr : Entity_Id) return Entity_Id
16186 while Present (Corresponding_Discriminant (D)) loop
16187 D := Corresponding_Discriminant (D);
16191 end Root_Corresponding_Discriminant;
16193 ------------------------------
16194 -- Search_Derivation_Levels --
16195 ------------------------------
16197 function Search_Derivation_Levels
16199 Discrim_Values : Elist_Id;
16200 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
16204 Result : Node_Or_Entity_Id;
16205 Result_Entity : Node_Id;
16208 -- If inappropriate type, return Error, this happens only in
16209 -- cascaded error situations, and we want to avoid a blow up.
16211 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
16215 -- Look deeper if possible. Use Stored_Constraints only for
16216 -- untagged types. For tagged types use the given constraint.
16217 -- This asymmetry needs explanation???
16219 if not Stored_Discrim_Values
16220 and then Present (Stored_Constraint (Ti))
16221 and then not Is_Tagged_Type (Ti)
16224 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
16227 Td : constant Entity_Id := Etype (Ti);
16231 Result := Discriminant;
16234 if Present (Stored_Constraint (Ti)) then
16236 Search_Derivation_Levels
16237 (Td, Stored_Constraint (Ti), True);
16240 Search_Derivation_Levels
16241 (Td, Discrim_Values, Stored_Discrim_Values);
16247 -- Extra underlying places to search, if not found above. For
16248 -- concurrent types, the relevant discriminant appears in the
16249 -- corresponding record. For a type derived from a private type
16250 -- without discriminant, the full view inherits the discriminants
16251 -- of the full view of the parent.
16253 if Result = Discriminant then
16254 if Is_Concurrent_Type (Ti)
16255 and then Present (Corresponding_Record_Type (Ti))
16258 Search_Derivation_Levels (
16259 Corresponding_Record_Type (Ti),
16261 Stored_Discrim_Values);
16263 elsif Is_Private_Type (Ti)
16264 and then not Has_Discriminants (Ti)
16265 and then Present (Full_View (Ti))
16266 and then Etype (Full_View (Ti)) /= Ti
16269 Search_Derivation_Levels (
16272 Stored_Discrim_Values);
16276 -- If Result is not a (reference to a) discriminant, return it,
16277 -- otherwise set Result_Entity to the discriminant.
16279 if Nkind (Result) = N_Defining_Identifier then
16280 pragma Assert (Result = Discriminant);
16281 Result_Entity := Result;
16284 if not Denotes_Discriminant (Result) then
16288 Result_Entity := Entity (Result);
16291 -- See if this level of derivation actually has discriminants
16292 -- because tagged derivations can add them, hence the lower
16293 -- levels need not have any.
16295 if not Has_Discriminants (Ti) then
16299 -- Scan Ti's discriminants for Result_Entity,
16300 -- and return its corresponding value, if any.
16302 Result_Entity := Original_Record_Component (Result_Entity);
16304 Assoc := First_Elmt (Discrim_Values);
16306 if Stored_Discrim_Values then
16307 Disc := First_Stored_Discriminant (Ti);
16309 Disc := First_Discriminant (Ti);
16312 while Present (Disc) loop
16313 pragma Assert (Present (Assoc));
16315 if Original_Record_Component (Disc) = Result_Entity then
16316 return Node (Assoc);
16321 if Stored_Discrim_Values then
16322 Next_Stored_Discriminant (Disc);
16324 Next_Discriminant (Disc);
16328 -- Could not find it
16331 end Search_Derivation_Levels;
16335 Result : Node_Or_Entity_Id;
16337 -- Start of processing for Get_Discriminant_Value
16340 -- ??? This routine is a gigantic mess and will be deleted. For the
16341 -- time being just test for the trivial case before calling recurse.
16343 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
16349 D := First_Discriminant (Typ_For_Constraint);
16350 E := First_Elmt (Constraint);
16351 while Present (D) loop
16352 if Chars (D) = Chars (Discriminant) then
16356 Next_Discriminant (D);
16362 Result := Search_Derivation_Levels
16363 (Typ_For_Constraint, Constraint, False);
16365 -- ??? hack to disappear when this routine is gone
16367 if Nkind (Result) = N_Defining_Identifier then
16373 D := First_Discriminant (Typ_For_Constraint);
16374 E := First_Elmt (Constraint);
16375 while Present (D) loop
16376 if Root_Corresponding_Discriminant (D) = Discriminant then
16380 Next_Discriminant (D);
16386 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
16388 end Get_Discriminant_Value;
16390 --------------------------
16391 -- Has_Range_Constraint --
16392 --------------------------
16394 function Has_Range_Constraint (N : Node_Id) return Boolean is
16395 C : constant Node_Id := Constraint (N);
16398 if Nkind (C) = N_Range_Constraint then
16401 elsif Nkind (C) = N_Digits_Constraint then
16403 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
16405 Present (Range_Constraint (C));
16407 elsif Nkind (C) = N_Delta_Constraint then
16408 return Present (Range_Constraint (C));
16413 end Has_Range_Constraint;
16415 ------------------------
16416 -- Inherit_Components --
16417 ------------------------
16419 function Inherit_Components
16421 Parent_Base : Entity_Id;
16422 Derived_Base : Entity_Id;
16423 Is_Tagged : Boolean;
16424 Inherit_Discr : Boolean;
16425 Discs : Elist_Id) return Elist_Id
16427 Assoc_List : constant Elist_Id := New_Elmt_List;
16429 procedure Inherit_Component
16430 (Old_C : Entity_Id;
16431 Plain_Discrim : Boolean := False;
16432 Stored_Discrim : Boolean := False);
16433 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
16434 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
16435 -- True, Old_C is a stored discriminant. If they are both false then
16436 -- Old_C is a regular component.
16438 -----------------------
16439 -- Inherit_Component --
16440 -----------------------
16442 procedure Inherit_Component
16443 (Old_C : Entity_Id;
16444 Plain_Discrim : Boolean := False;
16445 Stored_Discrim : Boolean := False)
16447 procedure Set_Anonymous_Type (Id : Entity_Id);
16448 -- Id denotes the entity of an access discriminant or anonymous
16449 -- access component. Set the type of Id to either the same type of
16450 -- Old_C or create a new one depending on whether the parent and
16451 -- the child types are in the same scope.
16453 ------------------------
16454 -- Set_Anonymous_Type --
16455 ------------------------
16457 procedure Set_Anonymous_Type (Id : Entity_Id) is
16458 Old_Typ : constant Entity_Id := Etype (Old_C);
16461 if Scope (Parent_Base) = Scope (Derived_Base) then
16462 Set_Etype (Id, Old_Typ);
16464 -- The parent and the derived type are in two different scopes.
16465 -- Reuse the type of the original discriminant / component by
16466 -- copying it in order to preserve all attributes.
16470 Typ : constant Entity_Id := New_Copy (Old_Typ);
16473 Set_Etype (Id, Typ);
16475 -- Since we do not generate component declarations for
16476 -- inherited components, associate the itype with the
16479 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
16480 Set_Scope (Typ, Derived_Base);
16483 end Set_Anonymous_Type;
16485 -- Local variables and constants
16487 New_C : constant Entity_Id := New_Copy (Old_C);
16489 Corr_Discrim : Entity_Id;
16490 Discrim : Entity_Id;
16492 -- Start of processing for Inherit_Component
16495 pragma Assert (not Is_Tagged or else not Stored_Discrim);
16497 Set_Parent (New_C, Parent (Old_C));
16499 -- Regular discriminants and components must be inserted in the scope
16500 -- of the Derived_Base. Do it here.
16502 if not Stored_Discrim then
16503 Enter_Name (New_C);
16506 -- For tagged types the Original_Record_Component must point to
16507 -- whatever this field was pointing to in the parent type. This has
16508 -- already been achieved by the call to New_Copy above.
16510 if not Is_Tagged then
16511 Set_Original_Record_Component (New_C, New_C);
16514 -- Set the proper type of an access discriminant
16516 if Ekind (New_C) = E_Discriminant
16517 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
16519 Set_Anonymous_Type (New_C);
16522 -- If we have inherited a component then see if its Etype contains
16523 -- references to Parent_Base discriminants. In this case, replace
16524 -- these references with the constraints given in Discs. We do not
16525 -- do this for the partial view of private types because this is
16526 -- not needed (only the components of the full view will be used
16527 -- for code generation) and cause problem. We also avoid this
16528 -- transformation in some error situations.
16530 if Ekind (New_C) = E_Component then
16532 -- Set the proper type of an anonymous access component
16534 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
16535 Set_Anonymous_Type (New_C);
16537 elsif (Is_Private_Type (Derived_Base)
16538 and then not Is_Generic_Type (Derived_Base))
16539 or else (Is_Empty_Elmt_List (Discs)
16540 and then not Expander_Active)
16542 Set_Etype (New_C, Etype (Old_C));
16545 -- The current component introduces a circularity of the
16548 -- limited with Pack_2;
16549 -- package Pack_1 is
16550 -- type T_1 is tagged record
16551 -- Comp : access Pack_2.T_2;
16557 -- package Pack_2 is
16558 -- type T_2 is new Pack_1.T_1 with ...;
16563 Constrain_Component_Type
16564 (Old_C, Derived_Base, N, Parent_Base, Discs));
16568 -- In derived tagged types it is illegal to reference a non
16569 -- discriminant component in the parent type. To catch this, mark
16570 -- these components with an Ekind of E_Void. This will be reset in
16571 -- Record_Type_Definition after processing the record extension of
16572 -- the derived type.
16574 -- If the declaration is a private extension, there is no further
16575 -- record extension to process, and the components retain their
16576 -- current kind, because they are visible at this point.
16578 if Is_Tagged and then Ekind (New_C) = E_Component
16579 and then Nkind (N) /= N_Private_Extension_Declaration
16581 Set_Ekind (New_C, E_Void);
16584 if Plain_Discrim then
16585 Set_Corresponding_Discriminant (New_C, Old_C);
16586 Build_Discriminal (New_C);
16588 -- If we are explicitly inheriting a stored discriminant it will be
16589 -- completely hidden.
16591 elsif Stored_Discrim then
16592 Set_Corresponding_Discriminant (New_C, Empty);
16593 Set_Discriminal (New_C, Empty);
16594 Set_Is_Completely_Hidden (New_C);
16596 -- Set the Original_Record_Component of each discriminant in the
16597 -- derived base to point to the corresponding stored that we just
16600 Discrim := First_Discriminant (Derived_Base);
16601 while Present (Discrim) loop
16602 Corr_Discrim := Corresponding_Discriminant (Discrim);
16604 -- Corr_Discrim could be missing in an error situation
16606 if Present (Corr_Discrim)
16607 and then Original_Record_Component (Corr_Discrim) = Old_C
16609 Set_Original_Record_Component (Discrim, New_C);
16612 Next_Discriminant (Discrim);
16615 Append_Entity (New_C, Derived_Base);
16618 if not Is_Tagged then
16619 Append_Elmt (Old_C, Assoc_List);
16620 Append_Elmt (New_C, Assoc_List);
16622 end Inherit_Component;
16624 -- Variables local to Inherit_Component
16626 Loc : constant Source_Ptr := Sloc (N);
16628 Parent_Discrim : Entity_Id;
16629 Stored_Discrim : Entity_Id;
16631 Component : Entity_Id;
16633 -- Start of processing for Inherit_Components
16636 if not Is_Tagged then
16637 Append_Elmt (Parent_Base, Assoc_List);
16638 Append_Elmt (Derived_Base, Assoc_List);
16641 -- Inherit parent discriminants if needed
16643 if Inherit_Discr then
16644 Parent_Discrim := First_Discriminant (Parent_Base);
16645 while Present (Parent_Discrim) loop
16646 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
16647 Next_Discriminant (Parent_Discrim);
16651 -- Create explicit stored discrims for untagged types when necessary
16653 if not Has_Unknown_Discriminants (Derived_Base)
16654 and then Has_Discriminants (Parent_Base)
16655 and then not Is_Tagged
16658 or else First_Discriminant (Parent_Base) /=
16659 First_Stored_Discriminant (Parent_Base))
16661 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
16662 while Present (Stored_Discrim) loop
16663 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
16664 Next_Stored_Discriminant (Stored_Discrim);
16668 -- See if we can apply the second transformation for derived types, as
16669 -- explained in point 6. in the comments above Build_Derived_Record_Type
16670 -- This is achieved by appending Derived_Base discriminants into Discs,
16671 -- which has the side effect of returning a non empty Discs list to the
16672 -- caller of Inherit_Components, which is what we want. This must be
16673 -- done for private derived types if there are explicit stored
16674 -- discriminants, to ensure that we can retrieve the values of the
16675 -- constraints provided in the ancestors.
16678 and then Is_Empty_Elmt_List (Discs)
16679 and then Present (First_Discriminant (Derived_Base))
16681 (not Is_Private_Type (Derived_Base)
16682 or else Is_Completely_Hidden
16683 (First_Stored_Discriminant (Derived_Base))
16684 or else Is_Generic_Type (Derived_Base))
16686 D := First_Discriminant (Derived_Base);
16687 while Present (D) loop
16688 Append_Elmt (New_Occurrence_Of (D, Loc), Discs);
16689 Next_Discriminant (D);
16693 -- Finally, inherit non-discriminant components unless they are not
16694 -- visible because defined or inherited from the full view of the
16695 -- parent. Don't inherit the _parent field of the parent type.
16697 Component := First_Entity (Parent_Base);
16698 while Present (Component) loop
16700 -- Ada 2005 (AI-251): Do not inherit components associated with
16701 -- secondary tags of the parent.
16703 if Ekind (Component) = E_Component
16704 and then Present (Related_Type (Component))
16708 elsif Ekind (Component) /= E_Component
16709 or else Chars (Component) = Name_uParent
16713 -- If the derived type is within the parent type's declarative
16714 -- region, then the components can still be inherited even though
16715 -- they aren't visible at this point. This can occur for cases
16716 -- such as within public child units where the components must
16717 -- become visible upon entering the child unit's private part.
16719 elsif not Is_Visible_Component (Component)
16720 and then not In_Open_Scopes (Scope (Parent_Base))
16724 elsif Ekind_In (Derived_Base, E_Private_Type,
16725 E_Limited_Private_Type)
16730 Inherit_Component (Component);
16733 Next_Entity (Component);
16736 -- For tagged derived types, inherited discriminants cannot be used in
16737 -- component declarations of the record extension part. To achieve this
16738 -- we mark the inherited discriminants as not visible.
16740 if Is_Tagged and then Inherit_Discr then
16741 D := First_Discriminant (Derived_Base);
16742 while Present (D) loop
16743 Set_Is_Immediately_Visible (D, False);
16744 Next_Discriminant (D);
16749 end Inherit_Components;
16751 -----------------------
16752 -- Is_Null_Extension --
16753 -----------------------
16755 function Is_Null_Extension (T : Entity_Id) return Boolean is
16756 Type_Decl : constant Node_Id := Parent (Base_Type (T));
16757 Comp_List : Node_Id;
16761 if Nkind (Type_Decl) /= N_Full_Type_Declaration
16762 or else not Is_Tagged_Type (T)
16763 or else Nkind (Type_Definition (Type_Decl)) /=
16764 N_Derived_Type_Definition
16765 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
16771 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
16773 if Present (Discriminant_Specifications (Type_Decl)) then
16776 elsif Present (Comp_List)
16777 and then Is_Non_Empty_List (Component_Items (Comp_List))
16779 Comp := First (Component_Items (Comp_List));
16781 -- Only user-defined components are relevant. The component list
16782 -- may also contain a parent component and internal components
16783 -- corresponding to secondary tags, but these do not determine
16784 -- whether this is a null extension.
16786 while Present (Comp) loop
16787 if Comes_From_Source (Comp) then
16798 end Is_Null_Extension;
16800 ------------------------------
16801 -- Is_Valid_Constraint_Kind --
16802 ------------------------------
16804 function Is_Valid_Constraint_Kind
16805 (T_Kind : Type_Kind;
16806 Constraint_Kind : Node_Kind) return Boolean
16810 when Enumeration_Kind |
16812 return Constraint_Kind = N_Range_Constraint;
16814 when Decimal_Fixed_Point_Kind =>
16815 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
16816 N_Range_Constraint);
16818 when Ordinary_Fixed_Point_Kind =>
16819 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
16820 N_Range_Constraint);
16823 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
16824 N_Range_Constraint);
16831 E_Incomplete_Type |
16834 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
16837 return True; -- Error will be detected later
16839 end Is_Valid_Constraint_Kind;
16841 --------------------------
16842 -- Is_Visible_Component --
16843 --------------------------
16845 function Is_Visible_Component
16847 N : Node_Id := Empty) return Boolean
16849 Original_Comp : Entity_Id := Empty;
16850 Original_Scope : Entity_Id;
16851 Type_Scope : Entity_Id;
16853 function Is_Local_Type (Typ : Entity_Id) return Boolean;
16854 -- Check whether parent type of inherited component is declared locally,
16855 -- possibly within a nested package or instance. The current scope is
16856 -- the derived record itself.
16858 -------------------
16859 -- Is_Local_Type --
16860 -------------------
16862 function Is_Local_Type (Typ : Entity_Id) return Boolean is
16866 Scop := Scope (Typ);
16867 while Present (Scop)
16868 and then Scop /= Standard_Standard
16870 if Scop = Scope (Current_Scope) then
16874 Scop := Scope (Scop);
16880 -- Start of processing for Is_Visible_Component
16883 if Ekind_In (C, E_Component, E_Discriminant) then
16884 Original_Comp := Original_Record_Component (C);
16887 if No (Original_Comp) then
16889 -- Premature usage, or previous error
16894 Original_Scope := Scope (Original_Comp);
16895 Type_Scope := Scope (Base_Type (Scope (C)));
16898 -- For an untagged type derived from a private type, the only visible
16899 -- components are new discriminants. In an instance all components are
16900 -- visible (see Analyze_Selected_Component).
16902 if not Is_Tagged_Type (Original_Scope) then
16903 return not Has_Private_Ancestor (Original_Scope)
16904 or else In_Open_Scopes (Scope (Original_Scope))
16905 or else In_Instance
16906 or else (Ekind (Original_Comp) = E_Discriminant
16907 and then Original_Scope = Type_Scope);
16909 -- If it is _Parent or _Tag, there is no visibility issue
16911 elsif not Comes_From_Source (Original_Comp) then
16914 -- Discriminants are visible unless the (private) type has unknown
16915 -- discriminants. If the discriminant reference is inserted for a
16916 -- discriminant check on a full view it is also visible.
16918 elsif Ekind (Original_Comp) = E_Discriminant
16920 (not Has_Unknown_Discriminants (Original_Scope)
16921 or else (Present (N)
16922 and then Nkind (N) = N_Selected_Component
16923 and then Nkind (Prefix (N)) = N_Type_Conversion
16924 and then not Comes_From_Source (Prefix (N))))
16928 -- In the body of an instantiation, no need to check for the visibility
16931 elsif In_Instance_Body then
16934 -- If the component has been declared in an ancestor which is currently
16935 -- a private type, then it is not visible. The same applies if the
16936 -- component's containing type is not in an open scope and the original
16937 -- component's enclosing type is a visible full view of a private type
16938 -- (which can occur in cases where an attempt is being made to reference
16939 -- a component in a sibling package that is inherited from a visible
16940 -- component of a type in an ancestor package; the component in the
16941 -- sibling package should not be visible even though the component it
16942 -- inherited from is visible). This does not apply however in the case
16943 -- where the scope of the type is a private child unit, or when the
16944 -- parent comes from a local package in which the ancestor is currently
16945 -- visible. The latter suppression of visibility is needed for cases
16946 -- that are tested in B730006.
16948 elsif Is_Private_Type (Original_Scope)
16950 (not Is_Private_Descendant (Type_Scope)
16951 and then not In_Open_Scopes (Type_Scope)
16952 and then Has_Private_Declaration (Original_Scope))
16954 -- If the type derives from an entity in a formal package, there
16955 -- are no additional visible components.
16957 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
16958 N_Formal_Package_Declaration
16962 -- if we are not in the private part of the current package, there
16963 -- are no additional visible components.
16965 elsif Ekind (Scope (Current_Scope)) = E_Package
16966 and then not In_Private_Part (Scope (Current_Scope))
16971 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
16972 and then In_Open_Scopes (Scope (Original_Scope))
16973 and then Is_Local_Type (Type_Scope);
16976 -- There is another weird way in which a component may be invisible when
16977 -- the private and the full view are not derived from the same ancestor.
16978 -- Here is an example :
16980 -- type A1 is tagged record F1 : integer; end record;
16981 -- type A2 is new A1 with record F2 : integer; end record;
16982 -- type T is new A1 with private;
16984 -- type T is new A2 with null record;
16986 -- In this case, the full view of T inherits F1 and F2 but the private
16987 -- view inherits only F1
16991 Ancestor : Entity_Id := Scope (C);
16995 if Ancestor = Original_Scope then
16997 elsif Ancestor = Etype (Ancestor) then
17001 Ancestor := Etype (Ancestor);
17005 end Is_Visible_Component;
17007 --------------------------
17008 -- Make_Class_Wide_Type --
17009 --------------------------
17011 procedure Make_Class_Wide_Type (T : Entity_Id) is
17012 CW_Type : Entity_Id;
17014 Next_E : Entity_Id;
17017 if Present (Class_Wide_Type (T)) then
17019 -- The class-wide type is a partially decorated entity created for a
17020 -- unanalyzed tagged type referenced through a limited with clause.
17021 -- When the tagged type is analyzed, its class-wide type needs to be
17022 -- redecorated. Note that we reuse the entity created by Decorate_
17023 -- Tagged_Type in order to preserve all links.
17025 if Materialize_Entity (Class_Wide_Type (T)) then
17026 CW_Type := Class_Wide_Type (T);
17027 Set_Materialize_Entity (CW_Type, False);
17029 -- The class wide type can have been defined by the partial view, in
17030 -- which case everything is already done.
17036 -- Default case, we need to create a new class-wide type
17040 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
17043 -- Inherit root type characteristics
17045 CW_Name := Chars (CW_Type);
17046 Next_E := Next_Entity (CW_Type);
17047 Copy_Node (T, CW_Type);
17048 Set_Comes_From_Source (CW_Type, False);
17049 Set_Chars (CW_Type, CW_Name);
17050 Set_Parent (CW_Type, Parent (T));
17051 Set_Next_Entity (CW_Type, Next_E);
17053 -- Ensure we have a new freeze node for the class-wide type. The partial
17054 -- view may have freeze action of its own, requiring a proper freeze
17055 -- node, and the same freeze node cannot be shared between the two
17058 Set_Has_Delayed_Freeze (CW_Type);
17059 Set_Freeze_Node (CW_Type, Empty);
17061 -- Customize the class-wide type: It has no prim. op., it cannot be
17062 -- abstract and its Etype points back to the specific root type.
17064 Set_Ekind (CW_Type, E_Class_Wide_Type);
17065 Set_Is_Tagged_Type (CW_Type, True);
17066 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
17067 Set_Is_Abstract_Type (CW_Type, False);
17068 Set_Is_Constrained (CW_Type, False);
17069 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
17071 if Ekind (T) = E_Class_Wide_Subtype then
17072 Set_Etype (CW_Type, Etype (Base_Type (T)));
17074 Set_Etype (CW_Type, T);
17077 -- If this is the class_wide type of a constrained subtype, it does
17078 -- not have discriminants.
17080 Set_Has_Discriminants (CW_Type,
17081 Has_Discriminants (T) and then not Is_Constrained (T));
17083 Set_Has_Unknown_Discriminants (CW_Type, True);
17084 Set_Class_Wide_Type (T, CW_Type);
17085 Set_Equivalent_Type (CW_Type, Empty);
17087 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
17089 Set_Class_Wide_Type (CW_Type, CW_Type);
17090 end Make_Class_Wide_Type;
17096 procedure Make_Index
17098 Related_Nod : Node_Id;
17099 Related_Id : Entity_Id := Empty;
17100 Suffix_Index : Nat := 1;
17101 In_Iter_Schm : Boolean := False)
17105 Def_Id : Entity_Id := Empty;
17106 Found : Boolean := False;
17109 -- For a discrete range used in a constrained array definition and
17110 -- defined by a range, an implicit conversion to the predefined type
17111 -- INTEGER is assumed if each bound is either a numeric literal, a named
17112 -- number, or an attribute, and the type of both bounds (prior to the
17113 -- implicit conversion) is the type universal_integer. Otherwise, both
17114 -- bounds must be of the same discrete type, other than universal
17115 -- integer; this type must be determinable independently of the
17116 -- context, but using the fact that the type must be discrete and that
17117 -- both bounds must have the same type.
17119 -- Character literals also have a universal type in the absence of
17120 -- of additional context, and are resolved to Standard_Character.
17122 if Nkind (I) = N_Range then
17124 -- The index is given by a range constraint. The bounds are known
17125 -- to be of a consistent type.
17127 if not Is_Overloaded (I) then
17130 -- For universal bounds, choose the specific predefined type
17132 if T = Universal_Integer then
17133 T := Standard_Integer;
17135 elsif T = Any_Character then
17136 Ambiguous_Character (Low_Bound (I));
17138 T := Standard_Character;
17141 -- The node may be overloaded because some user-defined operators
17142 -- are available, but if a universal interpretation exists it is
17143 -- also the selected one.
17145 elsif Universal_Interpretation (I) = Universal_Integer then
17146 T := Standard_Integer;
17152 Ind : Interp_Index;
17156 Get_First_Interp (I, Ind, It);
17157 while Present (It.Typ) loop
17158 if Is_Discrete_Type (It.Typ) then
17161 and then not Covers (It.Typ, T)
17162 and then not Covers (T, It.Typ)
17164 Error_Msg_N ("ambiguous bounds in discrete range", I);
17172 Get_Next_Interp (Ind, It);
17175 if T = Any_Type then
17176 Error_Msg_N ("discrete type required for range", I);
17177 Set_Etype (I, Any_Type);
17180 elsif T = Universal_Integer then
17181 T := Standard_Integer;
17186 if not Is_Discrete_Type (T) then
17187 Error_Msg_N ("discrete type required for range", I);
17188 Set_Etype (I, Any_Type);
17192 if Nkind (Low_Bound (I)) = N_Attribute_Reference
17193 and then Attribute_Name (Low_Bound (I)) = Name_First
17194 and then Is_Entity_Name (Prefix (Low_Bound (I)))
17195 and then Is_Type (Entity (Prefix (Low_Bound (I))))
17196 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (I))))
17198 -- The type of the index will be the type of the prefix, as long
17199 -- as the upper bound is 'Last of the same type.
17201 Def_Id := Entity (Prefix (Low_Bound (I)));
17203 if Nkind (High_Bound (I)) /= N_Attribute_Reference
17204 or else Attribute_Name (High_Bound (I)) /= Name_Last
17205 or else not Is_Entity_Name (Prefix (High_Bound (I)))
17206 or else Entity (Prefix (High_Bound (I))) /= Def_Id
17213 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
17215 elsif Nkind (I) = N_Subtype_Indication then
17217 -- The index is given by a subtype with a range constraint
17219 T := Base_Type (Entity (Subtype_Mark (I)));
17221 if not Is_Discrete_Type (T) then
17222 Error_Msg_N ("discrete type required for range", I);
17223 Set_Etype (I, Any_Type);
17227 R := Range_Expression (Constraint (I));
17230 Process_Range_Expr_In_Decl
17231 (R, Entity (Subtype_Mark (I)), In_Iter_Schm => In_Iter_Schm);
17233 elsif Nkind (I) = N_Attribute_Reference then
17235 -- The parser guarantees that the attribute is a RANGE attribute
17237 -- If the node denotes the range of a type mark, that is also the
17238 -- resulting type, and we do no need to create an Itype for it.
17240 if Is_Entity_Name (Prefix (I))
17241 and then Comes_From_Source (I)
17242 and then Is_Type (Entity (Prefix (I)))
17243 and then Is_Discrete_Type (Entity (Prefix (I)))
17245 Def_Id := Entity (Prefix (I));
17248 Analyze_And_Resolve (I);
17252 -- If none of the above, must be a subtype. We convert this to a
17253 -- range attribute reference because in the case of declared first
17254 -- named subtypes, the types in the range reference can be different
17255 -- from the type of the entity. A range attribute normalizes the
17256 -- reference and obtains the correct types for the bounds.
17258 -- This transformation is in the nature of an expansion, is only
17259 -- done if expansion is active. In particular, it is not done on
17260 -- formal generic types, because we need to retain the name of the
17261 -- original index for instantiation purposes.
17264 if not Is_Entity_Name (I) or else not Is_Type (Entity (I)) then
17265 Error_Msg_N ("invalid subtype mark in discrete range ", I);
17266 Set_Etype (I, Any_Integer);
17270 -- The type mark may be that of an incomplete type. It is only
17271 -- now that we can get the full view, previous analysis does
17272 -- not look specifically for a type mark.
17274 Set_Entity (I, Get_Full_View (Entity (I)));
17275 Set_Etype (I, Entity (I));
17276 Def_Id := Entity (I);
17278 if not Is_Discrete_Type (Def_Id) then
17279 Error_Msg_N ("discrete type required for index", I);
17280 Set_Etype (I, Any_Type);
17285 if Expander_Active then
17287 Make_Attribute_Reference (Sloc (I),
17288 Attribute_Name => Name_Range,
17289 Prefix => Relocate_Node (I)));
17291 -- The original was a subtype mark that does not freeze. This
17292 -- means that the rewritten version must not freeze either.
17294 Set_Must_Not_Freeze (I);
17295 Set_Must_Not_Freeze (Prefix (I));
17296 Analyze_And_Resolve (I);
17300 -- If expander is inactive, type is legal, nothing else to construct
17307 if not Is_Discrete_Type (T) then
17308 Error_Msg_N ("discrete type required for range", I);
17309 Set_Etype (I, Any_Type);
17312 elsif T = Any_Type then
17313 Set_Etype (I, Any_Type);
17317 -- We will now create the appropriate Itype to describe the range, but
17318 -- first a check. If we originally had a subtype, then we just label
17319 -- the range with this subtype. Not only is there no need to construct
17320 -- a new subtype, but it is wrong to do so for two reasons:
17322 -- 1. A legality concern, if we have a subtype, it must not freeze,
17323 -- and the Itype would cause freezing incorrectly
17325 -- 2. An efficiency concern, if we created an Itype, it would not be
17326 -- recognized as the same type for the purposes of eliminating
17327 -- checks in some circumstances.
17329 -- We signal this case by setting the subtype entity in Def_Id
17331 if No (Def_Id) then
17333 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
17334 Set_Etype (Def_Id, Base_Type (T));
17336 if Is_Signed_Integer_Type (T) then
17337 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
17339 elsif Is_Modular_Integer_Type (T) then
17340 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
17343 Set_Ekind (Def_Id, E_Enumeration_Subtype);
17344 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
17345 Set_First_Literal (Def_Id, First_Literal (T));
17348 Set_Size_Info (Def_Id, (T));
17349 Set_RM_Size (Def_Id, RM_Size (T));
17350 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
17352 Set_Scalar_Range (Def_Id, R);
17353 Conditional_Delay (Def_Id, T);
17355 -- In the subtype indication case, if the immediate parent of the
17356 -- new subtype is non-static, then the subtype we create is non-
17357 -- static, even if its bounds are static.
17359 if Nkind (I) = N_Subtype_Indication
17360 and then not Is_Static_Subtype (Entity (Subtype_Mark (I)))
17362 Set_Is_Non_Static_Subtype (Def_Id);
17366 -- Final step is to label the index with this constructed type
17368 Set_Etype (I, Def_Id);
17371 ------------------------------
17372 -- Modular_Type_Declaration --
17373 ------------------------------
17375 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
17376 Mod_Expr : constant Node_Id := Expression (Def);
17379 procedure Set_Modular_Size (Bits : Int);
17380 -- Sets RM_Size to Bits, and Esize to normal word size above this
17382 ----------------------
17383 -- Set_Modular_Size --
17384 ----------------------
17386 procedure Set_Modular_Size (Bits : Int) is
17388 Set_RM_Size (T, UI_From_Int (Bits));
17393 elsif Bits <= 16 then
17394 Init_Esize (T, 16);
17396 elsif Bits <= 32 then
17397 Init_Esize (T, 32);
17400 Init_Esize (T, System_Max_Binary_Modulus_Power);
17403 if not Non_Binary_Modulus (T)
17404 and then Esize (T) = RM_Size (T)
17406 Set_Is_Known_Valid (T);
17408 end Set_Modular_Size;
17410 -- Start of processing for Modular_Type_Declaration
17413 -- If the mod expression is (exactly) 2 * literal, where literal is
17414 -- 64 or less,then almost certainly the * was meant to be **. Warn.
17416 if Warn_On_Suspicious_Modulus_Value
17417 and then Nkind (Mod_Expr) = N_Op_Multiply
17418 and then Nkind (Left_Opnd (Mod_Expr)) = N_Integer_Literal
17419 and then Intval (Left_Opnd (Mod_Expr)) = Uint_2
17420 and then Nkind (Right_Opnd (Mod_Expr)) = N_Integer_Literal
17421 and then Intval (Right_Opnd (Mod_Expr)) <= Uint_64
17424 ("suspicious MOD value, was '*'* intended'??M?", Mod_Expr);
17427 -- Proceed with analysis of mod expression
17429 Analyze_And_Resolve (Mod_Expr, Any_Integer);
17431 Set_Ekind (T, E_Modular_Integer_Type);
17432 Init_Alignment (T);
17433 Set_Is_Constrained (T);
17435 if not Is_OK_Static_Expression (Mod_Expr) then
17436 Flag_Non_Static_Expr
17437 ("non-static expression used for modular type bound!", Mod_Expr);
17438 M_Val := 2 ** System_Max_Binary_Modulus_Power;
17440 M_Val := Expr_Value (Mod_Expr);
17444 Error_Msg_N ("modulus value must be positive", Mod_Expr);
17445 M_Val := 2 ** System_Max_Binary_Modulus_Power;
17448 Set_Modulus (T, M_Val);
17450 -- Create bounds for the modular type based on the modulus given in
17451 -- the type declaration and then analyze and resolve those bounds.
17453 Set_Scalar_Range (T,
17454 Make_Range (Sloc (Mod_Expr),
17455 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
17456 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
17458 -- Properly analyze the literals for the range. We do this manually
17459 -- because we can't go calling Resolve, since we are resolving these
17460 -- bounds with the type, and this type is certainly not complete yet.
17462 Set_Etype (Low_Bound (Scalar_Range (T)), T);
17463 Set_Etype (High_Bound (Scalar_Range (T)), T);
17464 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
17465 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
17467 -- Loop through powers of two to find number of bits required
17469 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
17473 if M_Val = 2 ** Bits then
17474 Set_Modular_Size (Bits);
17479 elsif M_Val < 2 ** Bits then
17480 Check_SPARK_Restriction ("modulus should be a power of 2", T);
17481 Set_Non_Binary_Modulus (T);
17483 if Bits > System_Max_Nonbinary_Modulus_Power then
17484 Error_Msg_Uint_1 :=
17485 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
17487 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
17488 Set_Modular_Size (System_Max_Binary_Modulus_Power);
17492 -- In the non-binary case, set size as per RM 13.3(55)
17494 Set_Modular_Size (Bits);
17501 -- If we fall through, then the size exceed System.Max_Binary_Modulus
17502 -- so we just signal an error and set the maximum size.
17504 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
17505 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
17507 Set_Modular_Size (System_Max_Binary_Modulus_Power);
17508 Init_Alignment (T);
17510 end Modular_Type_Declaration;
17512 --------------------------
17513 -- New_Concatenation_Op --
17514 --------------------------
17516 procedure New_Concatenation_Op (Typ : Entity_Id) is
17517 Loc : constant Source_Ptr := Sloc (Typ);
17520 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
17521 -- Create abbreviated declaration for the formal of a predefined
17522 -- Operator 'Op' of type 'Typ'
17524 --------------------
17525 -- Make_Op_Formal --
17526 --------------------
17528 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
17529 Formal : Entity_Id;
17531 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
17532 Set_Etype (Formal, Typ);
17533 Set_Mechanism (Formal, Default_Mechanism);
17535 end Make_Op_Formal;
17537 -- Start of processing for New_Concatenation_Op
17540 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
17542 Set_Ekind (Op, E_Operator);
17543 Set_Scope (Op, Current_Scope);
17544 Set_Etype (Op, Typ);
17545 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
17546 Set_Is_Immediately_Visible (Op);
17547 Set_Is_Intrinsic_Subprogram (Op);
17548 Set_Has_Completion (Op);
17549 Append_Entity (Op, Current_Scope);
17551 Set_Name_Entity_Id (Name_Op_Concat, Op);
17553 Append_Entity (Make_Op_Formal (Typ, Op), Op);
17554 Append_Entity (Make_Op_Formal (Typ, Op), Op);
17555 end New_Concatenation_Op;
17557 -------------------------
17558 -- OK_For_Limited_Init --
17559 -------------------------
17561 -- ???Check all calls of this, and compare the conditions under which it's
17564 function OK_For_Limited_Init
17566 Exp : Node_Id) return Boolean
17569 return Is_CPP_Constructor_Call (Exp)
17570 or else (Ada_Version >= Ada_2005
17571 and then not Debug_Flag_Dot_L
17572 and then OK_For_Limited_Init_In_05 (Typ, Exp));
17573 end OK_For_Limited_Init;
17575 -------------------------------
17576 -- OK_For_Limited_Init_In_05 --
17577 -------------------------------
17579 function OK_For_Limited_Init_In_05
17581 Exp : Node_Id) return Boolean
17584 -- An object of a limited interface type can be initialized with any
17585 -- expression of a nonlimited descendant type.
17587 if Is_Class_Wide_Type (Typ)
17588 and then Is_Limited_Interface (Typ)
17589 and then not Is_Limited_Type (Etype (Exp))
17594 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
17595 -- case of limited aggregates (including extension aggregates), and
17596 -- function calls. The function call may have been given in prefixed
17597 -- notation, in which case the original node is an indexed component.
17598 -- If the function is parameterless, the original node was an explicit
17599 -- dereference. The function may also be parameterless, in which case
17600 -- the source node is just an identifier.
17602 case Nkind (Original_Node (Exp)) is
17603 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
17606 when N_Identifier =>
17607 return Present (Entity (Original_Node (Exp)))
17608 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
17610 when N_Qualified_Expression =>
17612 OK_For_Limited_Init_In_05
17613 (Typ, Expression (Original_Node (Exp)));
17615 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
17616 -- with a function call, the expander has rewritten the call into an
17617 -- N_Type_Conversion node to force displacement of the pointer to
17618 -- reference the component containing the secondary dispatch table.
17619 -- Otherwise a type conversion is not a legal context.
17620 -- A return statement for a build-in-place function returning a
17621 -- synchronized type also introduces an unchecked conversion.
17623 when N_Type_Conversion |
17624 N_Unchecked_Type_Conversion =>
17625 return not Comes_From_Source (Exp)
17627 OK_For_Limited_Init_In_05
17628 (Typ, Expression (Original_Node (Exp)));
17630 when N_Indexed_Component |
17631 N_Selected_Component |
17632 N_Explicit_Dereference =>
17633 return Nkind (Exp) = N_Function_Call;
17635 -- A use of 'Input is a function call, hence allowed. Normally the
17636 -- attribute will be changed to a call, but the attribute by itself
17637 -- can occur with -gnatc.
17639 when N_Attribute_Reference =>
17640 return Attribute_Name (Original_Node (Exp)) = Name_Input;
17642 -- For a case expression, all dependent expressions must be legal
17644 when N_Case_Expression =>
17649 Alt := First (Alternatives (Original_Node (Exp)));
17650 while Present (Alt) loop
17651 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
17661 -- For an if expression, all dependent expressions must be legal
17663 when N_If_Expression =>
17665 Then_Expr : constant Node_Id :=
17666 Next (First (Expressions (Original_Node (Exp))));
17667 Else_Expr : constant Node_Id := Next (Then_Expr);
17669 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
17671 OK_For_Limited_Init_In_05 (Typ, Else_Expr);
17677 end OK_For_Limited_Init_In_05;
17679 -------------------------------------------
17680 -- Ordinary_Fixed_Point_Type_Declaration --
17681 -------------------------------------------
17683 procedure Ordinary_Fixed_Point_Type_Declaration
17687 Loc : constant Source_Ptr := Sloc (Def);
17688 Delta_Expr : constant Node_Id := Delta_Expression (Def);
17689 RRS : constant Node_Id := Real_Range_Specification (Def);
17690 Implicit_Base : Entity_Id;
17697 Check_Restriction (No_Fixed_Point, Def);
17699 -- Create implicit base type
17702 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
17703 Set_Etype (Implicit_Base, Implicit_Base);
17705 -- Analyze and process delta expression
17707 Analyze_And_Resolve (Delta_Expr, Any_Real);
17709 Check_Delta_Expression (Delta_Expr);
17710 Delta_Val := Expr_Value_R (Delta_Expr);
17712 Set_Delta_Value (Implicit_Base, Delta_Val);
17714 -- Compute default small from given delta, which is the largest power
17715 -- of two that does not exceed the given delta value.
17725 if Delta_Val < Ureal_1 then
17726 while Delta_Val < Tmp loop
17727 Tmp := Tmp / Ureal_2;
17728 Scale := Scale + 1;
17733 Tmp := Tmp * Ureal_2;
17734 exit when Tmp > Delta_Val;
17735 Scale := Scale - 1;
17739 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
17742 Set_Small_Value (Implicit_Base, Small_Val);
17744 -- If no range was given, set a dummy range
17746 if RRS <= Empty_Or_Error then
17747 Low_Val := -Small_Val;
17748 High_Val := Small_Val;
17750 -- Otherwise analyze and process given range
17754 Low : constant Node_Id := Low_Bound (RRS);
17755 High : constant Node_Id := High_Bound (RRS);
17758 Analyze_And_Resolve (Low, Any_Real);
17759 Analyze_And_Resolve (High, Any_Real);
17760 Check_Real_Bound (Low);
17761 Check_Real_Bound (High);
17763 -- Obtain and set the range
17765 Low_Val := Expr_Value_R (Low);
17766 High_Val := Expr_Value_R (High);
17768 if Low_Val > High_Val then
17769 Error_Msg_NE ("??fixed point type& has null range", Def, T);
17774 -- The range for both the implicit base and the declared first subtype
17775 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
17776 -- set a temporary range in place. Note that the bounds of the base
17777 -- type will be widened to be symmetrical and to fill the available
17778 -- bits when the type is frozen.
17780 -- We could do this with all discrete types, and probably should, but
17781 -- we absolutely have to do it for fixed-point, since the end-points
17782 -- of the range and the size are determined by the small value, which
17783 -- could be reset before the freeze point.
17785 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
17786 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
17788 -- Complete definition of first subtype
17790 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
17791 Set_Etype (T, Implicit_Base);
17792 Init_Size_Align (T);
17793 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
17794 Set_Small_Value (T, Small_Val);
17795 Set_Delta_Value (T, Delta_Val);
17796 Set_Is_Constrained (T);
17798 end Ordinary_Fixed_Point_Type_Declaration;
17800 ----------------------------------------
17801 -- Prepare_Private_Subtype_Completion --
17802 ----------------------------------------
17804 procedure Prepare_Private_Subtype_Completion
17806 Related_Nod : Node_Id)
17808 Id_B : constant Entity_Id := Base_Type (Id);
17809 Full_B : constant Entity_Id := Full_View (Id_B);
17813 if Present (Full_B) then
17815 -- The Base_Type is already completed, we can complete the subtype
17816 -- now. We have to create a new entity with the same name, Thus we
17817 -- can't use Create_Itype.
17819 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
17820 Set_Is_Itype (Full);
17821 Set_Associated_Node_For_Itype (Full, Related_Nod);
17822 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
17825 -- The parent subtype may be private, but the base might not, in some
17826 -- nested instances. In that case, the subtype does not need to be
17827 -- exchanged. It would still be nice to make private subtypes and their
17828 -- bases consistent at all times ???
17830 if Is_Private_Type (Id_B) then
17831 Append_Elmt (Id, Private_Dependents (Id_B));
17833 end Prepare_Private_Subtype_Completion;
17835 ---------------------------
17836 -- Process_Discriminants --
17837 ---------------------------
17839 procedure Process_Discriminants
17841 Prev : Entity_Id := Empty)
17843 Elist : constant Elist_Id := New_Elmt_List;
17846 Discr_Number : Uint;
17847 Discr_Type : Entity_Id;
17848 Default_Present : Boolean := False;
17849 Default_Not_Present : Boolean := False;
17852 -- A composite type other than an array type can have discriminants.
17853 -- On entry, the current scope is the composite type.
17855 -- The discriminants are initially entered into the scope of the type
17856 -- via Enter_Name with the default Ekind of E_Void to prevent premature
17857 -- use, as explained at the end of this procedure.
17859 Discr := First (Discriminant_Specifications (N));
17860 while Present (Discr) loop
17861 Enter_Name (Defining_Identifier (Discr));
17863 -- For navigation purposes we add a reference to the discriminant
17864 -- in the entity for the type. If the current declaration is a
17865 -- completion, place references on the partial view. Otherwise the
17866 -- type is the current scope.
17868 if Present (Prev) then
17870 -- The references go on the partial view, if present. If the
17871 -- partial view has discriminants, the references have been
17872 -- generated already.
17874 if not Has_Discriminants (Prev) then
17875 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
17879 (Current_Scope, Defining_Identifier (Discr), 'd');
17882 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
17883 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
17885 -- Ada 2005 (AI-254)
17887 if Present (Access_To_Subprogram_Definition
17888 (Discriminant_Type (Discr)))
17889 and then Protected_Present (Access_To_Subprogram_Definition
17890 (Discriminant_Type (Discr)))
17893 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
17897 Find_Type (Discriminant_Type (Discr));
17898 Discr_Type := Etype (Discriminant_Type (Discr));
17900 if Error_Posted (Discriminant_Type (Discr)) then
17901 Discr_Type := Any_Type;
17905 if Is_Access_Type (Discr_Type) then
17907 -- Ada 2005 (AI-230): Access discriminant allowed in non-limited
17910 if Ada_Version < Ada_2005 then
17911 Check_Access_Discriminant_Requires_Limited
17912 (Discr, Discriminant_Type (Discr));
17915 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
17917 ("(Ada 83) access discriminant not allowed", Discr);
17920 elsif not Is_Discrete_Type (Discr_Type) then
17921 Error_Msg_N ("discriminants must have a discrete or access type",
17922 Discriminant_Type (Discr));
17925 Set_Etype (Defining_Identifier (Discr), Discr_Type);
17927 -- If a discriminant specification includes the assignment compound
17928 -- delimiter followed by an expression, the expression is the default
17929 -- expression of the discriminant; the default expression must be of
17930 -- the type of the discriminant. (RM 3.7.1) Since this expression is
17931 -- a default expression, we do the special preanalysis, since this
17932 -- expression does not freeze (see "Handling of Default and Per-
17933 -- Object Expressions" in spec of package Sem).
17935 if Present (Expression (Discr)) then
17936 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
17938 if Nkind (N) = N_Formal_Type_Declaration then
17940 ("discriminant defaults not allowed for formal type",
17941 Expression (Discr));
17943 -- Flag an error for a tagged type with defaulted discriminants,
17944 -- excluding limited tagged types when compiling for Ada 2012
17945 -- (see AI05-0214).
17947 elsif Is_Tagged_Type (Current_Scope)
17948 and then (not Is_Limited_Type (Current_Scope)
17949 or else Ada_Version < Ada_2012)
17950 and then Comes_From_Source (N)
17952 -- Note: see similar test in Check_Or_Process_Discriminants, to
17953 -- handle the (illegal) case of the completion of an untagged
17954 -- view with discriminants with defaults by a tagged full view.
17955 -- We skip the check if Discr does not come from source, to
17956 -- account for the case of an untagged derived type providing
17957 -- defaults for a renamed discriminant from a private untagged
17958 -- ancestor with a tagged full view (ACATS B460006).
17960 if Ada_Version >= Ada_2012 then
17962 ("discriminants of nonlimited tagged type cannot have"
17964 Expression (Discr));
17967 ("discriminants of tagged type cannot have defaults",
17968 Expression (Discr));
17972 Default_Present := True;
17973 Append_Elmt (Expression (Discr), Elist);
17975 -- Tag the defining identifiers for the discriminants with
17976 -- their corresponding default expressions from the tree.
17978 Set_Discriminant_Default_Value
17979 (Defining_Identifier (Discr), Expression (Discr));
17983 Default_Not_Present := True;
17986 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
17987 -- Discr_Type but with the null-exclusion attribute
17989 if Ada_Version >= Ada_2005 then
17991 -- Ada 2005 (AI-231): Static checks
17993 if Can_Never_Be_Null (Discr_Type) then
17994 Null_Exclusion_Static_Checks (Discr);
17996 elsif Is_Access_Type (Discr_Type)
17997 and then Null_Exclusion_Present (Discr)
17999 -- No need to check itypes because in their case this check
18000 -- was done at their point of creation
18002 and then not Is_Itype (Discr_Type)
18004 if Can_Never_Be_Null (Discr_Type) then
18006 ("`NOT NULL` not allowed (& already excludes null)",
18011 Set_Etype (Defining_Identifier (Discr),
18012 Create_Null_Excluding_Itype
18014 Related_Nod => Discr));
18016 -- Check for improper null exclusion if the type is otherwise
18017 -- legal for a discriminant.
18019 elsif Null_Exclusion_Present (Discr)
18020 and then Is_Discrete_Type (Discr_Type)
18023 ("null exclusion can only apply to an access type", Discr);
18026 -- Ada 2005 (AI-402): access discriminants of nonlimited types
18027 -- can't have defaults. Synchronized types, or types that are
18028 -- explicitly limited are fine, but special tests apply to derived
18029 -- types in generics: in a generic body we have to assume the
18030 -- worst, and therefore defaults are not allowed if the parent is
18031 -- a generic formal private type (see ACATS B370001).
18033 if Is_Access_Type (Discr_Type) and then Default_Present then
18034 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
18035 or else Is_Limited_Record (Current_Scope)
18036 or else Is_Concurrent_Type (Current_Scope)
18037 or else Is_Concurrent_Record_Type (Current_Scope)
18038 or else Ekind (Current_Scope) = E_Limited_Private_Type
18040 if not Is_Derived_Type (Current_Scope)
18041 or else not Is_Generic_Type (Etype (Current_Scope))
18042 or else not In_Package_Body (Scope (Etype (Current_Scope)))
18043 or else Limited_Present
18044 (Type_Definition (Parent (Current_Scope)))
18049 Error_Msg_N ("access discriminants of nonlimited types",
18050 Expression (Discr));
18051 Error_Msg_N ("\cannot have defaults", Expression (Discr));
18054 elsif Present (Expression (Discr)) then
18056 ("(Ada 2005) access discriminants of nonlimited types",
18057 Expression (Discr));
18058 Error_Msg_N ("\cannot have defaults", Expression (Discr));
18063 -- A discriminant cannot be volatile. This check is only relevant
18064 -- when SPARK_Mode is on as it is not standard Ada legality rule
18065 -- (SPARK RM 7.1.3(6)).
18068 and then Is_SPARK_Volatile (Defining_Identifier (Discr))
18070 Error_Msg_N ("discriminant cannot be volatile", Discr);
18076 -- An element list consisting of the default expressions of the
18077 -- discriminants is constructed in the above loop and used to set
18078 -- the Discriminant_Constraint attribute for the type. If an object
18079 -- is declared of this (record or task) type without any explicit
18080 -- discriminant constraint given, this element list will form the
18081 -- actual parameters for the corresponding initialization procedure
18084 Set_Discriminant_Constraint (Current_Scope, Elist);
18085 Set_Stored_Constraint (Current_Scope, No_Elist);
18087 -- Default expressions must be provided either for all or for none
18088 -- of the discriminants of a discriminant part. (RM 3.7.1)
18090 if Default_Present and then Default_Not_Present then
18092 ("incomplete specification of defaults for discriminants", N);
18095 -- The use of the name of a discriminant is not allowed in default
18096 -- expressions of a discriminant part if the specification of the
18097 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
18099 -- To detect this, the discriminant names are entered initially with an
18100 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
18101 -- attempt to use a void entity (for example in an expression that is
18102 -- type-checked) produces the error message: premature usage. Now after
18103 -- completing the semantic analysis of the discriminant part, we can set
18104 -- the Ekind of all the discriminants appropriately.
18106 Discr := First (Discriminant_Specifications (N));
18107 Discr_Number := Uint_1;
18108 while Present (Discr) loop
18109 Id := Defining_Identifier (Discr);
18110 Set_Ekind (Id, E_Discriminant);
18111 Init_Component_Location (Id);
18113 Set_Discriminant_Number (Id, Discr_Number);
18115 -- Make sure this is always set, even in illegal programs
18117 Set_Corresponding_Discriminant (Id, Empty);
18119 -- Initialize the Original_Record_Component to the entity itself.
18120 -- Inherit_Components will propagate the right value to
18121 -- discriminants in derived record types.
18123 Set_Original_Record_Component (Id, Id);
18125 -- Create the discriminal for the discriminant
18127 Build_Discriminal (Id);
18130 Discr_Number := Discr_Number + 1;
18133 Set_Has_Discriminants (Current_Scope);
18134 end Process_Discriminants;
18136 -----------------------
18137 -- Process_Full_View --
18138 -----------------------
18140 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
18141 Priv_Parent : Entity_Id;
18142 Full_Parent : Entity_Id;
18143 Full_Indic : Node_Id;
18145 procedure Collect_Implemented_Interfaces
18147 Ifaces : Elist_Id);
18148 -- Ada 2005: Gather all the interfaces that Typ directly or
18149 -- inherently implements. Duplicate entries are not added to
18150 -- the list Ifaces.
18152 ------------------------------------
18153 -- Collect_Implemented_Interfaces --
18154 ------------------------------------
18156 procedure Collect_Implemented_Interfaces
18161 Iface_Elmt : Elmt_Id;
18164 -- Abstract interfaces are only associated with tagged record types
18166 if not Is_Tagged_Type (Typ)
18167 or else not Is_Record_Type (Typ)
18172 -- Recursively climb to the ancestors
18174 if Etype (Typ) /= Typ
18176 -- Protect the frontend against wrong cyclic declarations like:
18178 -- type B is new A with private;
18179 -- type C is new A with private;
18181 -- type B is new C with null record;
18182 -- type C is new B with null record;
18184 and then Etype (Typ) /= Priv_T
18185 and then Etype (Typ) /= Full_T
18187 -- Keep separate the management of private type declarations
18189 if Ekind (Typ) = E_Record_Type_With_Private then
18191 -- Handle the following illegal usage:
18192 -- type Private_Type is tagged private;
18194 -- type Private_Type is new Type_Implementing_Iface;
18196 if Present (Full_View (Typ))
18197 and then Etype (Typ) /= Full_View (Typ)
18199 if Is_Interface (Etype (Typ)) then
18200 Append_Unique_Elmt (Etype (Typ), Ifaces);
18203 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
18206 -- Non-private types
18209 if Is_Interface (Etype (Typ)) then
18210 Append_Unique_Elmt (Etype (Typ), Ifaces);
18213 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
18217 -- Handle entities in the list of abstract interfaces
18219 if Present (Interfaces (Typ)) then
18220 Iface_Elmt := First_Elmt (Interfaces (Typ));
18221 while Present (Iface_Elmt) loop
18222 Iface := Node (Iface_Elmt);
18224 pragma Assert (Is_Interface (Iface));
18226 if not Contain_Interface (Iface, Ifaces) then
18227 Append_Elmt (Iface, Ifaces);
18228 Collect_Implemented_Interfaces (Iface, Ifaces);
18231 Next_Elmt (Iface_Elmt);
18234 end Collect_Implemented_Interfaces;
18236 -- Start of processing for Process_Full_View
18239 -- First some sanity checks that must be done after semantic
18240 -- decoration of the full view and thus cannot be placed with other
18241 -- similar checks in Find_Type_Name
18243 if not Is_Limited_Type (Priv_T)
18244 and then (Is_Limited_Type (Full_T)
18245 or else Is_Limited_Composite (Full_T))
18247 if In_Instance then
18251 ("completion of nonlimited type cannot be limited", Full_T);
18252 Explain_Limited_Type (Full_T, Full_T);
18255 elsif Is_Abstract_Type (Full_T)
18256 and then not Is_Abstract_Type (Priv_T)
18259 ("completion of nonabstract type cannot be abstract", Full_T);
18261 elsif Is_Tagged_Type (Priv_T)
18262 and then Is_Limited_Type (Priv_T)
18263 and then not Is_Limited_Type (Full_T)
18265 -- If pragma CPP_Class was applied to the private declaration
18266 -- propagate the limitedness to the full-view
18268 if Is_CPP_Class (Priv_T) then
18269 Set_Is_Limited_Record (Full_T);
18271 -- GNAT allow its own definition of Limited_Controlled to disobey
18272 -- this rule in order in ease the implementation. This test is safe
18273 -- because Root_Controlled is defined in a child of System that
18274 -- normal programs are not supposed to use.
18276 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
18277 Set_Is_Limited_Composite (Full_T);
18280 ("completion of limited tagged type must be limited", Full_T);
18283 elsif Is_Generic_Type (Priv_T) then
18284 Error_Msg_N ("generic type cannot have a completion", Full_T);
18287 -- Check that ancestor interfaces of private and full views are
18288 -- consistent. We omit this check for synchronized types because
18289 -- they are performed on the corresponding record type when frozen.
18291 if Ada_Version >= Ada_2005
18292 and then Is_Tagged_Type (Priv_T)
18293 and then Is_Tagged_Type (Full_T)
18294 and then not Is_Concurrent_Type (Full_T)
18298 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
18299 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
18302 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
18303 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
18305 -- Ada 2005 (AI-251): The partial view shall be a descendant of
18306 -- an interface type if and only if the full type is descendant
18307 -- of the interface type (AARM 7.3 (7.3/2)).
18309 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
18311 if Present (Iface) then
18313 ("interface in partial view& not implemented by full type "
18314 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
18317 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
18319 if Present (Iface) then
18321 ("interface & not implemented by partial view "
18322 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
18327 if Is_Tagged_Type (Priv_T)
18328 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
18329 and then Is_Derived_Type (Full_T)
18331 Priv_Parent := Etype (Priv_T);
18333 -- The full view of a private extension may have been transformed
18334 -- into an unconstrained derived type declaration and a subtype
18335 -- declaration (see build_derived_record_type for details).
18337 if Nkind (N) = N_Subtype_Declaration then
18338 Full_Indic := Subtype_Indication (N);
18339 Full_Parent := Etype (Base_Type (Full_T));
18341 Full_Indic := Subtype_Indication (Type_Definition (N));
18342 Full_Parent := Etype (Full_T);
18345 -- Check that the parent type of the full type is a descendant of
18346 -- the ancestor subtype given in the private extension. If either
18347 -- entity has an Etype equal to Any_Type then we had some previous
18348 -- error situation [7.3(8)].
18350 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
18353 -- Ada 2005 (AI-251): Interfaces in the full type can be given in
18354 -- any order. Therefore we don't have to check that its parent must
18355 -- be a descendant of the parent of the private type declaration.
18357 elsif Is_Interface (Priv_Parent)
18358 and then Is_Interface (Full_Parent)
18362 -- Ada 2005 (AI-251): If the parent of the private type declaration
18363 -- is an interface there is no need to check that it is an ancestor
18364 -- of the associated full type declaration. The required tests for
18365 -- this case are performed by Build_Derived_Record_Type.
18367 elsif not Is_Interface (Base_Type (Priv_Parent))
18368 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
18371 ("parent of full type must descend from parent"
18372 & " of private extension", Full_Indic);
18374 -- First check a formal restriction, and then proceed with checking
18375 -- Ada rules. Since the formal restriction is not a serious error, we
18376 -- don't prevent further error detection for this check, hence the
18381 -- In formal mode, when completing a private extension the type
18382 -- named in the private part must be exactly the same as that
18383 -- named in the visible part.
18385 if Priv_Parent /= Full_Parent then
18386 Error_Msg_Name_1 := Chars (Priv_Parent);
18387 Check_SPARK_Restriction ("% expected", Full_Indic);
18390 -- Check the rules of 7.3(10): if the private extension inherits
18391 -- known discriminants, then the full type must also inherit those
18392 -- discriminants from the same (ancestor) type, and the parent
18393 -- subtype of the full type must be constrained if and only if
18394 -- the ancestor subtype of the private extension is constrained.
18396 if No (Discriminant_Specifications (Parent (Priv_T)))
18397 and then not Has_Unknown_Discriminants (Priv_T)
18398 and then Has_Discriminants (Base_Type (Priv_Parent))
18401 Priv_Indic : constant Node_Id :=
18402 Subtype_Indication (Parent (Priv_T));
18404 Priv_Constr : constant Boolean :=
18405 Is_Constrained (Priv_Parent)
18407 Nkind (Priv_Indic) = N_Subtype_Indication
18409 Is_Constrained (Entity (Priv_Indic));
18411 Full_Constr : constant Boolean :=
18412 Is_Constrained (Full_Parent)
18414 Nkind (Full_Indic) = N_Subtype_Indication
18416 Is_Constrained (Entity (Full_Indic));
18418 Priv_Discr : Entity_Id;
18419 Full_Discr : Entity_Id;
18422 Priv_Discr := First_Discriminant (Priv_Parent);
18423 Full_Discr := First_Discriminant (Full_Parent);
18424 while Present (Priv_Discr) and then Present (Full_Discr) loop
18425 if Original_Record_Component (Priv_Discr) =
18426 Original_Record_Component (Full_Discr)
18428 Corresponding_Discriminant (Priv_Discr) =
18429 Corresponding_Discriminant (Full_Discr)
18436 Next_Discriminant (Priv_Discr);
18437 Next_Discriminant (Full_Discr);
18440 if Present (Priv_Discr) or else Present (Full_Discr) then
18442 ("full view must inherit discriminants of the parent"
18443 & " type used in the private extension", Full_Indic);
18445 elsif Priv_Constr and then not Full_Constr then
18447 ("parent subtype of full type must be constrained",
18450 elsif Full_Constr and then not Priv_Constr then
18452 ("parent subtype of full type must be unconstrained",
18457 -- Check the rules of 7.3(12): if a partial view has neither
18458 -- known or unknown discriminants, then the full type
18459 -- declaration shall define a definite subtype.
18461 elsif not Has_Unknown_Discriminants (Priv_T)
18462 and then not Has_Discriminants (Priv_T)
18463 and then not Is_Constrained (Full_T)
18466 ("full view must define a constrained type if partial view"
18467 & " has no discriminants", Full_T);
18470 -- ??????? Do we implement the following properly ?????
18471 -- If the ancestor subtype of a private extension has constrained
18472 -- discriminants, then the parent subtype of the full view shall
18473 -- impose a statically matching constraint on those discriminants
18478 -- For untagged types, verify that a type without discriminants is
18479 -- not completed with an unconstrained type. A separate error message
18480 -- is produced if the full type has defaulted discriminants.
18482 if not Is_Indefinite_Subtype (Priv_T)
18483 and then Is_Indefinite_Subtype (Full_T)
18485 Error_Msg_Sloc := Sloc (Parent (Priv_T));
18487 ("full view of& not compatible with declaration#",
18490 if not Is_Tagged_Type (Full_T) then
18492 ("\one is constrained, the other unconstrained", Full_T);
18497 -- AI-419: verify that the use of "limited" is consistent
18500 Orig_Decl : constant Node_Id := Original_Node (N);
18503 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
18504 and then not Limited_Present (Parent (Priv_T))
18505 and then not Synchronized_Present (Parent (Priv_T))
18506 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
18508 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
18509 and then Limited_Present (Type_Definition (Orig_Decl))
18512 ("full view of non-limited extension cannot be limited", N);
18516 -- Ada 2005 (AI-443): A synchronized private extension must be
18517 -- completed by a task or protected type.
18519 if Ada_Version >= Ada_2005
18520 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
18521 and then Synchronized_Present (Parent (Priv_T))
18522 and then not Is_Concurrent_Type (Full_T)
18524 Error_Msg_N ("full view of synchronized extension must " &
18525 "be synchronized type", N);
18528 -- Ada 2005 AI-363: if the full view has discriminants with
18529 -- defaults, it is illegal to declare constrained access subtypes
18530 -- whose designated type is the current type. This allows objects
18531 -- of the type that are declared in the heap to be unconstrained.
18533 if not Has_Unknown_Discriminants (Priv_T)
18534 and then not Has_Discriminants (Priv_T)
18535 and then Has_Discriminants (Full_T)
18537 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
18539 Set_Has_Constrained_Partial_View (Full_T);
18540 Set_Has_Constrained_Partial_View (Priv_T);
18543 -- Create a full declaration for all its subtypes recorded in
18544 -- Private_Dependents and swap them similarly to the base type. These
18545 -- are subtypes that have been define before the full declaration of
18546 -- the private type. We also swap the entry in Private_Dependents list
18547 -- so we can properly restore the private view on exit from the scope.
18550 Priv_Elmt : Elmt_Id;
18555 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
18556 while Present (Priv_Elmt) loop
18557 Priv := Node (Priv_Elmt);
18559 if Ekind_In (Priv, E_Private_Subtype,
18560 E_Limited_Private_Subtype,
18561 E_Record_Subtype_With_Private)
18563 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
18564 Set_Is_Itype (Full);
18565 Set_Parent (Full, Parent (Priv));
18566 Set_Associated_Node_For_Itype (Full, N);
18568 -- Now we need to complete the private subtype, but since the
18569 -- base type has already been swapped, we must also swap the
18570 -- subtypes (and thus, reverse the arguments in the call to
18571 -- Complete_Private_Subtype).
18573 Copy_And_Swap (Priv, Full);
18574 Complete_Private_Subtype (Full, Priv, Full_T, N);
18575 Replace_Elmt (Priv_Elmt, Full);
18578 Next_Elmt (Priv_Elmt);
18582 -- If the private view was tagged, copy the new primitive operations
18583 -- from the private view to the full view.
18585 if Is_Tagged_Type (Full_T) then
18587 Disp_Typ : Entity_Id;
18588 Full_List : Elist_Id;
18590 Prim_Elmt : Elmt_Id;
18591 Priv_List : Elist_Id;
18595 L : Elist_Id) return Boolean;
18596 -- Determine whether list L contains element E
18604 L : Elist_Id) return Boolean
18606 List_Elmt : Elmt_Id;
18609 List_Elmt := First_Elmt (L);
18610 while Present (List_Elmt) loop
18611 if Node (List_Elmt) = E then
18615 Next_Elmt (List_Elmt);
18621 -- Start of processing
18624 if Is_Tagged_Type (Priv_T) then
18625 Priv_List := Primitive_Operations (Priv_T);
18626 Prim_Elmt := First_Elmt (Priv_List);
18628 -- In the case of a concurrent type completing a private tagged
18629 -- type, primitives may have been declared in between the two
18630 -- views. These subprograms need to be wrapped the same way
18631 -- entries and protected procedures are handled because they
18632 -- cannot be directly shared by the two views.
18634 if Is_Concurrent_Type (Full_T) then
18636 Conc_Typ : constant Entity_Id :=
18637 Corresponding_Record_Type (Full_T);
18638 Curr_Nod : Node_Id := Parent (Conc_Typ);
18639 Wrap_Spec : Node_Id;
18642 while Present (Prim_Elmt) loop
18643 Prim := Node (Prim_Elmt);
18645 if Comes_From_Source (Prim)
18646 and then not Is_Abstract_Subprogram (Prim)
18649 Make_Subprogram_Declaration (Sloc (Prim),
18653 Obj_Typ => Conc_Typ,
18655 Parameter_Specifications (
18658 Insert_After (Curr_Nod, Wrap_Spec);
18659 Curr_Nod := Wrap_Spec;
18661 Analyze (Wrap_Spec);
18664 Next_Elmt (Prim_Elmt);
18670 -- For non-concurrent types, transfer explicit primitives, but
18671 -- omit those inherited from the parent of the private view
18672 -- since they will be re-inherited later on.
18675 Full_List := Primitive_Operations (Full_T);
18677 while Present (Prim_Elmt) loop
18678 Prim := Node (Prim_Elmt);
18680 if Comes_From_Source (Prim)
18681 and then not Contains (Prim, Full_List)
18683 Append_Elmt (Prim, Full_List);
18686 Next_Elmt (Prim_Elmt);
18690 -- Untagged private view
18693 Full_List := Primitive_Operations (Full_T);
18695 -- In this case the partial view is untagged, so here we locate
18696 -- all of the earlier primitives that need to be treated as
18697 -- dispatching (those that appear between the two views). Note
18698 -- that these additional operations must all be new operations
18699 -- (any earlier operations that override inherited operations
18700 -- of the full view will already have been inserted in the
18701 -- primitives list, marked by Check_Operation_From_Private_View
18702 -- as dispatching. Note that implicit "/=" operators are
18703 -- excluded from being added to the primitives list since they
18704 -- shouldn't be treated as dispatching (tagged "/=" is handled
18707 Prim := Next_Entity (Full_T);
18708 while Present (Prim) and then Prim /= Priv_T loop
18709 if Ekind_In (Prim, E_Procedure, E_Function) then
18710 Disp_Typ := Find_Dispatching_Type (Prim);
18712 if Disp_Typ = Full_T
18713 and then (Chars (Prim) /= Name_Op_Ne
18714 or else Comes_From_Source (Prim))
18716 Check_Controlling_Formals (Full_T, Prim);
18718 if not Is_Dispatching_Operation (Prim) then
18719 Append_Elmt (Prim, Full_List);
18720 Set_Is_Dispatching_Operation (Prim, True);
18721 Set_DT_Position (Prim, No_Uint);
18724 elsif Is_Dispatching_Operation (Prim)
18725 and then Disp_Typ /= Full_T
18728 -- Verify that it is not otherwise controlled by a
18729 -- formal or a return value of type T.
18731 Check_Controlling_Formals (Disp_Typ, Prim);
18735 Next_Entity (Prim);
18739 -- For the tagged case, the two views can share the same primitive
18740 -- operations list and the same class-wide type. Update attributes
18741 -- of the class-wide type which depend on the full declaration.
18743 if Is_Tagged_Type (Priv_T) then
18744 Set_Direct_Primitive_Operations (Priv_T, Full_List);
18745 Set_Class_Wide_Type
18746 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
18748 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
18753 -- Ada 2005 AI 161: Check preelaborable initialization consistency
18755 if Known_To_Have_Preelab_Init (Priv_T) then
18757 -- Case where there is a pragma Preelaborable_Initialization. We
18758 -- always allow this in predefined units, which is cheating a bit,
18759 -- but it means we don't have to struggle to meet the requirements in
18760 -- the RM for having Preelaborable Initialization. Otherwise we
18761 -- require that the type meets the RM rules. But we can't check that
18762 -- yet, because of the rule about overriding Initialize, so we simply
18763 -- set a flag that will be checked at freeze time.
18765 if not In_Predefined_Unit (Full_T) then
18766 Set_Must_Have_Preelab_Init (Full_T);
18770 -- If pragma CPP_Class was applied to the private type declaration,
18771 -- propagate it now to the full type declaration.
18773 if Is_CPP_Class (Priv_T) then
18774 Set_Is_CPP_Class (Full_T);
18775 Set_Convention (Full_T, Convention_CPP);
18777 -- Check that components of imported CPP types do not have default
18780 Check_CPP_Type_Has_No_Defaults (Full_T);
18783 -- If the private view has user specified stream attributes, then so has
18786 -- Why the test, how could these flags be already set in Full_T ???
18788 if Has_Specified_Stream_Read (Priv_T) then
18789 Set_Has_Specified_Stream_Read (Full_T);
18792 if Has_Specified_Stream_Write (Priv_T) then
18793 Set_Has_Specified_Stream_Write (Full_T);
18796 if Has_Specified_Stream_Input (Priv_T) then
18797 Set_Has_Specified_Stream_Input (Full_T);
18800 if Has_Specified_Stream_Output (Priv_T) then
18801 Set_Has_Specified_Stream_Output (Full_T);
18804 -- Propagate invariants to full type
18806 if Has_Invariants (Priv_T) then
18807 Set_Has_Invariants (Full_T);
18808 Set_Invariant_Procedure (Full_T, Invariant_Procedure (Priv_T));
18811 if Has_Inheritable_Invariants (Priv_T) then
18812 Set_Has_Inheritable_Invariants (Full_T);
18815 -- Propagate predicates to full type, and predicate function if already
18816 -- defined. It is not clear that this can actually happen? the partial
18817 -- view cannot be frozen yet, and the predicate function has not been
18818 -- built. Still it is a cheap check and seems safer to make it.
18820 if Has_Predicates (Priv_T) then
18821 if Present (Predicate_Function (Priv_T)) then
18822 Set_Predicate_Function (Full_T, Predicate_Function (Priv_T));
18825 Set_Has_Predicates (Full_T);
18827 end Process_Full_View;
18829 -----------------------------------
18830 -- Process_Incomplete_Dependents --
18831 -----------------------------------
18833 procedure Process_Incomplete_Dependents
18835 Full_T : Entity_Id;
18838 Inc_Elmt : Elmt_Id;
18839 Priv_Dep : Entity_Id;
18840 New_Subt : Entity_Id;
18842 Disc_Constraint : Elist_Id;
18845 if No (Private_Dependents (Inc_T)) then
18849 -- Itypes that may be generated by the completion of an incomplete
18850 -- subtype are not used by the back-end and not attached to the tree.
18851 -- They are created only for constraint-checking purposes.
18853 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
18854 while Present (Inc_Elmt) loop
18855 Priv_Dep := Node (Inc_Elmt);
18857 if Ekind (Priv_Dep) = E_Subprogram_Type then
18859 -- An Access_To_Subprogram type may have a return type or a
18860 -- parameter type that is incomplete. Replace with the full view.
18862 if Etype (Priv_Dep) = Inc_T then
18863 Set_Etype (Priv_Dep, Full_T);
18867 Formal : Entity_Id;
18870 Formal := First_Formal (Priv_Dep);
18871 while Present (Formal) loop
18872 if Etype (Formal) = Inc_T then
18873 Set_Etype (Formal, Full_T);
18876 Next_Formal (Formal);
18880 elsif Is_Overloadable (Priv_Dep) then
18882 -- If a subprogram in the incomplete dependents list is primitive
18883 -- for a tagged full type then mark it as a dispatching operation,
18884 -- check whether it overrides an inherited subprogram, and check
18885 -- restrictions on its controlling formals. Note that a protected
18886 -- operation is never dispatching: only its wrapper operation
18887 -- (which has convention Ada) is.
18889 if Is_Tagged_Type (Full_T)
18890 and then Is_Primitive (Priv_Dep)
18891 and then Convention (Priv_Dep) /= Convention_Protected
18893 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
18894 Set_Is_Dispatching_Operation (Priv_Dep);
18895 Check_Controlling_Formals (Full_T, Priv_Dep);
18898 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
18900 -- Can happen during processing of a body before the completion
18901 -- of a TA type. Ignore, because spec is also on dependent list.
18905 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
18906 -- corresponding subtype of the full view.
18908 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
18909 Set_Subtype_Indication
18910 (Parent (Priv_Dep), New_Occurrence_Of (Full_T, Sloc (Priv_Dep)));
18911 Set_Etype (Priv_Dep, Full_T);
18912 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
18913 Set_Analyzed (Parent (Priv_Dep), False);
18915 -- Reanalyze the declaration, suppressing the call to
18916 -- Enter_Name to avoid duplicate names.
18918 Analyze_Subtype_Declaration
18919 (N => Parent (Priv_Dep),
18922 -- Dependent is a subtype
18925 -- We build a new subtype indication using the full view of the
18926 -- incomplete parent. The discriminant constraints have been
18927 -- elaborated already at the point of the subtype declaration.
18929 New_Subt := Create_Itype (E_Void, N);
18931 if Has_Discriminants (Full_T) then
18932 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
18934 Disc_Constraint := No_Elist;
18937 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
18938 Set_Full_View (Priv_Dep, New_Subt);
18941 Next_Elmt (Inc_Elmt);
18943 end Process_Incomplete_Dependents;
18945 --------------------------------
18946 -- Process_Range_Expr_In_Decl --
18947 --------------------------------
18949 procedure Process_Range_Expr_In_Decl
18952 Check_List : List_Id := Empty_List;
18953 R_Check_Off : Boolean := False;
18954 In_Iter_Schm : Boolean := False)
18957 R_Checks : Check_Result;
18958 Insert_Node : Node_Id;
18959 Def_Id : Entity_Id;
18962 Analyze_And_Resolve (R, Base_Type (T));
18964 if Nkind (R) = N_Range then
18966 -- In SPARK, all ranges should be static, with the exception of the
18967 -- discrete type definition of a loop parameter specification.
18969 if not In_Iter_Schm
18970 and then not Is_Static_Range (R)
18972 Check_SPARK_Restriction ("range should be static", R);
18975 Lo := Low_Bound (R);
18976 Hi := High_Bound (R);
18978 -- We need to ensure validity of the bounds here, because if we
18979 -- go ahead and do the expansion, then the expanded code will get
18980 -- analyzed with range checks suppressed and we miss the check.
18981 -- Validity checks on the range of a quantified expression are
18982 -- delayed until the construct is transformed into a loop.
18984 if Nkind (Parent (R)) /= N_Loop_Parameter_Specification
18985 or else Nkind (Parent (Parent (R))) /= N_Quantified_Expression
18987 Validity_Check_Range (R);
18990 -- If there were errors in the declaration, try and patch up some
18991 -- common mistakes in the bounds. The cases handled are literals
18992 -- which are Integer where the expected type is Real and vice versa.
18993 -- These corrections allow the compilation process to proceed further
18994 -- along since some basic assumptions of the format of the bounds
18997 if Etype (R) = Any_Type then
18998 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
19000 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
19002 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
19004 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
19006 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
19008 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
19010 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
19012 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
19019 -- If the bounds of the range have been mistakenly given as string
19020 -- literals (perhaps in place of character literals), then an error
19021 -- has already been reported, but we rewrite the string literal as a
19022 -- bound of the range's type to avoid blowups in later processing
19023 -- that looks at static values.
19025 if Nkind (Lo) = N_String_Literal then
19027 Make_Attribute_Reference (Sloc (Lo),
19028 Attribute_Name => Name_First,
19029 Prefix => New_Occurrence_Of (T, Sloc (Lo))));
19030 Analyze_And_Resolve (Lo);
19033 if Nkind (Hi) = N_String_Literal then
19035 Make_Attribute_Reference (Sloc (Hi),
19036 Attribute_Name => Name_First,
19037 Prefix => New_Occurrence_Of (T, Sloc (Hi))));
19038 Analyze_And_Resolve (Hi);
19041 -- If bounds aren't scalar at this point then exit, avoiding
19042 -- problems with further processing of the range in this procedure.
19044 if not Is_Scalar_Type (Etype (Lo)) then
19048 -- Resolve (actually Sem_Eval) has checked that the bounds are in
19049 -- then range of the base type. Here we check whether the bounds
19050 -- are in the range of the subtype itself. Note that if the bounds
19051 -- represent the null range the Constraint_Error exception should
19054 -- ??? The following code should be cleaned up as follows
19056 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
19057 -- is done in the call to Range_Check (R, T); below
19059 -- 2. The use of R_Check_Off should be investigated and possibly
19060 -- removed, this would clean up things a bit.
19062 if Is_Null_Range (Lo, Hi) then
19066 -- Capture values of bounds and generate temporaries for them
19067 -- if needed, before applying checks, since checks may cause
19068 -- duplication of the expression without forcing evaluation.
19070 -- The forced evaluation removes side effects from expressions,
19071 -- which should occur also in GNATprove mode. Otherwise, we end up
19072 -- with unexpected insertions of actions at places where this is
19073 -- not supposed to occur, e.g. on default parameters of a call.
19075 if Expander_Active or GNATprove_Mode then
19076 Force_Evaluation (Lo);
19077 Force_Evaluation (Hi);
19080 -- We use a flag here instead of suppressing checks on the
19081 -- type because the type we check against isn't necessarily
19082 -- the place where we put the check.
19084 if not R_Check_Off then
19085 R_Checks := Get_Range_Checks (R, T);
19087 -- Look up tree to find an appropriate insertion point. We
19088 -- can't just use insert_actions because later processing
19089 -- depends on the insertion node. Prior to Ada 2012 the
19090 -- insertion point could only be a declaration or a loop, but
19091 -- quantified expressions can appear within any context in an
19092 -- expression, and the insertion point can be any statement,
19093 -- pragma, or declaration.
19095 Insert_Node := Parent (R);
19096 while Present (Insert_Node) loop
19098 Nkind (Insert_Node) in N_Declaration
19101 (Insert_Node, N_Component_Declaration,
19102 N_Loop_Parameter_Specification,
19103 N_Function_Specification,
19104 N_Procedure_Specification);
19106 exit when Nkind (Insert_Node) in N_Later_Decl_Item
19107 or else Nkind (Insert_Node) in
19108 N_Statement_Other_Than_Procedure_Call
19109 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
19112 Insert_Node := Parent (Insert_Node);
19115 -- Why would Type_Decl not be present??? Without this test,
19116 -- short regression tests fail.
19118 if Present (Insert_Node) then
19120 -- Case of loop statement. Verify that the range is part
19121 -- of the subtype indication of the iteration scheme.
19123 if Nkind (Insert_Node) = N_Loop_Statement then
19128 Indic := Parent (R);
19129 while Present (Indic)
19130 and then Nkind (Indic) /= N_Subtype_Indication
19132 Indic := Parent (Indic);
19135 if Present (Indic) then
19136 Def_Id := Etype (Subtype_Mark (Indic));
19138 Insert_Range_Checks
19142 Sloc (Insert_Node),
19144 Do_Before => True);
19148 -- Insertion before a declaration. If the declaration
19149 -- includes discriminants, the list of applicable checks
19150 -- is given by the caller.
19152 elsif Nkind (Insert_Node) in N_Declaration then
19153 Def_Id := Defining_Identifier (Insert_Node);
19155 if (Ekind (Def_Id) = E_Record_Type
19156 and then Depends_On_Discriminant (R))
19158 (Ekind (Def_Id) = E_Protected_Type
19159 and then Has_Discriminants (Def_Id))
19161 Append_Range_Checks
19163 Check_List, Def_Id, Sloc (Insert_Node), R);
19166 Insert_Range_Checks
19168 Insert_Node, Def_Id, Sloc (Insert_Node), R);
19172 -- Insertion before a statement. Range appears in the
19173 -- context of a quantified expression. Insertion will
19174 -- take place when expression is expanded.
19183 -- Case of other than an explicit N_Range node
19185 -- The forced evaluation removes side effects from expressions, which
19186 -- should occur also in GNATprove mode. Otherwise, we end up with
19187 -- unexpected insertions of actions at places where this is not
19188 -- supposed to occur, e.g. on default parameters of a call.
19190 elsif Expander_Active or GNATprove_Mode then
19191 Get_Index_Bounds (R, Lo, Hi);
19192 Force_Evaluation (Lo);
19193 Force_Evaluation (Hi);
19195 end Process_Range_Expr_In_Decl;
19197 --------------------------------------
19198 -- Process_Real_Range_Specification --
19199 --------------------------------------
19201 procedure Process_Real_Range_Specification (Def : Node_Id) is
19202 Spec : constant Node_Id := Real_Range_Specification (Def);
19205 Err : Boolean := False;
19207 procedure Analyze_Bound (N : Node_Id);
19208 -- Analyze and check one bound
19210 -------------------
19211 -- Analyze_Bound --
19212 -------------------
19214 procedure Analyze_Bound (N : Node_Id) is
19216 Analyze_And_Resolve (N, Any_Real);
19218 if not Is_OK_Static_Expression (N) then
19219 Flag_Non_Static_Expr
19220 ("bound in real type definition is not static!", N);
19225 -- Start of processing for Process_Real_Range_Specification
19228 if Present (Spec) then
19229 Lo := Low_Bound (Spec);
19230 Hi := High_Bound (Spec);
19231 Analyze_Bound (Lo);
19232 Analyze_Bound (Hi);
19234 -- If error, clear away junk range specification
19237 Set_Real_Range_Specification (Def, Empty);
19240 end Process_Real_Range_Specification;
19242 ---------------------
19243 -- Process_Subtype --
19244 ---------------------
19246 function Process_Subtype
19248 Related_Nod : Node_Id;
19249 Related_Id : Entity_Id := Empty;
19250 Suffix : Character := ' ') return Entity_Id
19253 Def_Id : Entity_Id;
19254 Error_Node : Node_Id;
19255 Full_View_Id : Entity_Id;
19256 Subtype_Mark_Id : Entity_Id;
19258 May_Have_Null_Exclusion : Boolean;
19260 procedure Check_Incomplete (T : Entity_Id);
19261 -- Called to verify that an incomplete type is not used prematurely
19263 ----------------------
19264 -- Check_Incomplete --
19265 ----------------------
19267 procedure Check_Incomplete (T : Entity_Id) is
19269 -- Ada 2005 (AI-412): Incomplete subtypes are legal
19271 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
19273 not (Ada_Version >= Ada_2005
19275 (Nkind (Parent (T)) = N_Subtype_Declaration
19277 (Nkind (Parent (T)) = N_Subtype_Indication
19278 and then Nkind (Parent (Parent (T))) =
19279 N_Subtype_Declaration)))
19281 Error_Msg_N ("invalid use of type before its full declaration", T);
19283 end Check_Incomplete;
19285 -- Start of processing for Process_Subtype
19288 -- Case of no constraints present
19290 if Nkind (S) /= N_Subtype_Indication then
19292 Check_Incomplete (S);
19295 -- Ada 2005 (AI-231): Static check
19297 if Ada_Version >= Ada_2005
19298 and then Present (P)
19299 and then Null_Exclusion_Present (P)
19300 and then Nkind (P) /= N_Access_To_Object_Definition
19301 and then not Is_Access_Type (Entity (S))
19303 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
19306 -- The following is ugly, can't we have a range or even a flag???
19308 May_Have_Null_Exclusion :=
19309 Nkind_In (P, N_Access_Definition,
19310 N_Access_Function_Definition,
19311 N_Access_Procedure_Definition,
19312 N_Access_To_Object_Definition,
19314 N_Component_Definition)
19316 Nkind_In (P, N_Derived_Type_Definition,
19317 N_Discriminant_Specification,
19318 N_Formal_Object_Declaration,
19319 N_Object_Declaration,
19320 N_Object_Renaming_Declaration,
19321 N_Parameter_Specification,
19322 N_Subtype_Declaration);
19324 -- Create an Itype that is a duplicate of Entity (S) but with the
19325 -- null-exclusion attribute.
19327 if May_Have_Null_Exclusion
19328 and then Is_Access_Type (Entity (S))
19329 and then Null_Exclusion_Present (P)
19331 -- No need to check the case of an access to object definition.
19332 -- It is correct to define double not-null pointers.
19335 -- type Not_Null_Int_Ptr is not null access Integer;
19336 -- type Acc is not null access Not_Null_Int_Ptr;
19338 and then Nkind (P) /= N_Access_To_Object_Definition
19340 if Can_Never_Be_Null (Entity (S)) then
19341 case Nkind (Related_Nod) is
19342 when N_Full_Type_Declaration =>
19343 if Nkind (Type_Definition (Related_Nod))
19344 in N_Array_Type_Definition
19348 (Component_Definition
19349 (Type_Definition (Related_Nod)));
19352 Subtype_Indication (Type_Definition (Related_Nod));
19355 when N_Subtype_Declaration =>
19356 Error_Node := Subtype_Indication (Related_Nod);
19358 when N_Object_Declaration =>
19359 Error_Node := Object_Definition (Related_Nod);
19361 when N_Component_Declaration =>
19363 Subtype_Indication (Component_Definition (Related_Nod));
19365 when N_Allocator =>
19366 Error_Node := Expression (Related_Nod);
19369 pragma Assert (False);
19370 Error_Node := Related_Nod;
19374 ("`NOT NULL` not allowed (& already excludes null)",
19380 Create_Null_Excluding_Itype
19382 Related_Nod => P));
19383 Set_Entity (S, Etype (S));
19388 -- Case of constraint present, so that we have an N_Subtype_Indication
19389 -- node (this node is created only if constraints are present).
19392 Find_Type (Subtype_Mark (S));
19394 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
19396 (Nkind (Parent (S)) = N_Subtype_Declaration
19397 and then Is_Itype (Defining_Identifier (Parent (S))))
19399 Check_Incomplete (Subtype_Mark (S));
19403 Subtype_Mark_Id := Entity (Subtype_Mark (S));
19405 -- Explicit subtype declaration case
19407 if Nkind (P) = N_Subtype_Declaration then
19408 Def_Id := Defining_Identifier (P);
19410 -- Explicit derived type definition case
19412 elsif Nkind (P) = N_Derived_Type_Definition then
19413 Def_Id := Defining_Identifier (Parent (P));
19415 -- Implicit case, the Def_Id must be created as an implicit type.
19416 -- The one exception arises in the case of concurrent types, array
19417 -- and access types, where other subsidiary implicit types may be
19418 -- created and must appear before the main implicit type. In these
19419 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
19420 -- has not yet been called to create Def_Id.
19423 if Is_Array_Type (Subtype_Mark_Id)
19424 or else Is_Concurrent_Type (Subtype_Mark_Id)
19425 or else Is_Access_Type (Subtype_Mark_Id)
19429 -- For the other cases, we create a new unattached Itype,
19430 -- and set the indication to ensure it gets attached later.
19434 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
19438 -- If the kind of constraint is invalid for this kind of type,
19439 -- then give an error, and then pretend no constraint was given.
19441 if not Is_Valid_Constraint_Kind
19442 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
19445 ("incorrect constraint for this kind of type", Constraint (S));
19447 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
19449 -- Set Ekind of orphan itype, to prevent cascaded errors
19451 if Present (Def_Id) then
19452 Set_Ekind (Def_Id, Ekind (Any_Type));
19455 -- Make recursive call, having got rid of the bogus constraint
19457 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
19460 -- Remaining processing depends on type. Select on Base_Type kind to
19461 -- ensure getting to the concrete type kind in the case of a private
19462 -- subtype (needed when only doing semantic analysis).
19464 case Ekind (Base_Type (Subtype_Mark_Id)) is
19465 when Access_Kind =>
19467 -- If this is a constraint on a class-wide type, discard it.
19468 -- There is currently no way to express a partial discriminant
19469 -- constraint on a type with unknown discriminants. This is
19470 -- a pathology that the ACATS wisely decides not to test.
19472 if Is_Class_Wide_Type (Designated_Type (Subtype_Mark_Id)) then
19473 if Comes_From_Source (S) then
19475 ("constraint on class-wide type ignored??",
19479 if Nkind (P) = N_Subtype_Declaration then
19480 Set_Subtype_Indication (P,
19481 New_Occurrence_Of (Subtype_Mark_Id, Sloc (S)));
19484 return Subtype_Mark_Id;
19487 Constrain_Access (Def_Id, S, Related_Nod);
19490 and then Is_Itype (Designated_Type (Def_Id))
19491 and then Nkind (Related_Nod) = N_Subtype_Declaration
19492 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
19494 Build_Itype_Reference
19495 (Designated_Type (Def_Id), Related_Nod);
19499 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
19501 when Decimal_Fixed_Point_Kind =>
19502 Constrain_Decimal (Def_Id, S);
19504 when Enumeration_Kind =>
19505 Constrain_Enumeration (Def_Id, S);
19507 when Ordinary_Fixed_Point_Kind =>
19508 Constrain_Ordinary_Fixed (Def_Id, S);
19511 Constrain_Float (Def_Id, S);
19513 when Integer_Kind =>
19514 Constrain_Integer (Def_Id, S);
19516 when E_Record_Type |
19519 E_Incomplete_Type =>
19520 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
19522 if Ekind (Def_Id) = E_Incomplete_Type then
19523 Set_Private_Dependents (Def_Id, New_Elmt_List);
19526 when Private_Kind =>
19527 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
19528 Set_Private_Dependents (Def_Id, New_Elmt_List);
19530 -- In case of an invalid constraint prevent further processing
19531 -- since the type constructed is missing expected fields.
19533 if Etype (Def_Id) = Any_Type then
19537 -- If the full view is that of a task with discriminants,
19538 -- we must constrain both the concurrent type and its
19539 -- corresponding record type. Otherwise we will just propagate
19540 -- the constraint to the full view, if available.
19542 if Present (Full_View (Subtype_Mark_Id))
19543 and then Has_Discriminants (Subtype_Mark_Id)
19544 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
19547 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
19549 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
19550 Constrain_Concurrent (Full_View_Id, S,
19551 Related_Nod, Related_Id, Suffix);
19552 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
19553 Set_Full_View (Def_Id, Full_View_Id);
19555 -- Introduce an explicit reference to the private subtype,
19556 -- to prevent scope anomalies in gigi if first use appears
19557 -- in a nested context, e.g. a later function body.
19558 -- Should this be generated in other contexts than a full
19559 -- type declaration?
19561 if Is_Itype (Def_Id)
19563 Nkind (Parent (P)) = N_Full_Type_Declaration
19565 Build_Itype_Reference (Def_Id, Parent (P));
19569 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
19572 when Concurrent_Kind =>
19573 Constrain_Concurrent (Def_Id, S,
19574 Related_Nod, Related_Id, Suffix);
19577 Error_Msg_N ("invalid subtype mark in subtype indication", S);
19580 -- Size and Convention are always inherited from the base type
19582 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
19583 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
19587 end Process_Subtype;
19589 ---------------------------------------
19590 -- Check_Anonymous_Access_Components --
19591 ---------------------------------------
19593 procedure Check_Anonymous_Access_Components
19594 (Typ_Decl : Node_Id;
19597 Comp_List : Node_Id)
19599 Loc : constant Source_Ptr := Sloc (Typ_Decl);
19600 Anon_Access : Entity_Id;
19603 Comp_Def : Node_Id;
19605 Type_Def : Node_Id;
19607 procedure Build_Incomplete_Type_Declaration;
19608 -- If the record type contains components that include an access to the
19609 -- current record, then create an incomplete type declaration for the
19610 -- record, to be used as the designated type of the anonymous access.
19611 -- This is done only once, and only if there is no previous partial
19612 -- view of the type.
19614 function Designates_T (Subt : Node_Id) return Boolean;
19615 -- Check whether a node designates the enclosing record type, or 'Class
19618 function Mentions_T (Acc_Def : Node_Id) return Boolean;
19619 -- Check whether an access definition includes a reference to
19620 -- the enclosing record type. The reference can be a subtype mark
19621 -- in the access definition itself, a 'Class attribute reference, or
19622 -- recursively a reference appearing in a parameter specification
19623 -- or result definition of an access_to_subprogram definition.
19625 --------------------------------------
19626 -- Build_Incomplete_Type_Declaration --
19627 --------------------------------------
19629 procedure Build_Incomplete_Type_Declaration is
19634 -- Is_Tagged indicates whether the type is tagged. It is tagged if
19635 -- it's "is new ... with record" or else "is tagged record ...".
19637 Is_Tagged : constant Boolean :=
19638 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
19641 (Record_Extension_Part (Type_Definition (Typ_Decl))))
19643 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
19644 and then Tagged_Present (Type_Definition (Typ_Decl)));
19647 -- If there is a previous partial view, no need to create a new one
19648 -- If the partial view, given by Prev, is incomplete, If Prev is
19649 -- a private declaration, full declaration is flagged accordingly.
19651 if Prev /= Typ then
19653 Make_Class_Wide_Type (Prev);
19654 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
19655 Set_Etype (Class_Wide_Type (Typ), Typ);
19660 elsif Has_Private_Declaration (Typ) then
19662 -- If we refer to T'Class inside T, and T is the completion of a
19663 -- private type, then we need to make sure the class-wide type
19667 Make_Class_Wide_Type (Typ);
19672 -- If there was a previous anonymous access type, the incomplete
19673 -- type declaration will have been created already.
19675 elsif Present (Current_Entity (Typ))
19676 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
19677 and then Full_View (Current_Entity (Typ)) = Typ
19680 and then Comes_From_Source (Current_Entity (Typ))
19681 and then not Is_Tagged_Type (Current_Entity (Typ))
19683 Make_Class_Wide_Type (Typ);
19685 ("incomplete view of tagged type should be declared tagged??",
19686 Parent (Current_Entity (Typ)));
19691 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
19692 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
19694 -- Type has already been inserted into the current scope. Remove
19695 -- it, and add incomplete declaration for type, so that subsequent
19696 -- anonymous access types can use it. The entity is unchained from
19697 -- the homonym list and from immediate visibility. After analysis,
19698 -- the entity in the incomplete declaration becomes immediately
19699 -- visible in the record declaration that follows.
19701 H := Current_Entity (Typ);
19704 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
19707 and then Homonym (H) /= Typ
19709 H := Homonym (Typ);
19712 Set_Homonym (H, Homonym (Typ));
19715 Insert_Before (Typ_Decl, Decl);
19717 Set_Full_View (Inc_T, Typ);
19721 -- Create a common class-wide type for both views, and set the
19722 -- Etype of the class-wide type to the full view.
19724 Make_Class_Wide_Type (Inc_T);
19725 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
19726 Set_Etype (Class_Wide_Type (Typ), Typ);
19729 end Build_Incomplete_Type_Declaration;
19735 function Designates_T (Subt : Node_Id) return Boolean is
19736 Type_Id : constant Name_Id := Chars (Typ);
19738 function Names_T (Nam : Node_Id) return Boolean;
19739 -- The record type has not been introduced in the current scope
19740 -- yet, so we must examine the name of the type itself, either
19741 -- an identifier T, or an expanded name of the form P.T, where
19742 -- P denotes the current scope.
19748 function Names_T (Nam : Node_Id) return Boolean is
19750 if Nkind (Nam) = N_Identifier then
19751 return Chars (Nam) = Type_Id;
19753 elsif Nkind (Nam) = N_Selected_Component then
19754 if Chars (Selector_Name (Nam)) = Type_Id then
19755 if Nkind (Prefix (Nam)) = N_Identifier then
19756 return Chars (Prefix (Nam)) = Chars (Current_Scope);
19758 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
19759 return Chars (Selector_Name (Prefix (Nam))) =
19760 Chars (Current_Scope);
19774 -- Start of processing for Designates_T
19777 if Nkind (Subt) = N_Identifier then
19778 return Chars (Subt) = Type_Id;
19780 -- Reference can be through an expanded name which has not been
19781 -- analyzed yet, and which designates enclosing scopes.
19783 elsif Nkind (Subt) = N_Selected_Component then
19784 if Names_T (Subt) then
19787 -- Otherwise it must denote an entity that is already visible.
19788 -- The access definition may name a subtype of the enclosing
19789 -- type, if there is a previous incomplete declaration for it.
19792 Find_Selected_Component (Subt);
19794 Is_Entity_Name (Subt)
19795 and then Scope (Entity (Subt)) = Current_Scope
19797 (Chars (Base_Type (Entity (Subt))) = Type_Id
19799 (Is_Class_Wide_Type (Entity (Subt))
19801 Chars (Etype (Base_Type (Entity (Subt)))) =
19805 -- A reference to the current type may appear as the prefix of
19806 -- a 'Class attribute.
19808 elsif Nkind (Subt) = N_Attribute_Reference
19809 and then Attribute_Name (Subt) = Name_Class
19811 return Names_T (Prefix (Subt));
19822 function Mentions_T (Acc_Def : Node_Id) return Boolean is
19823 Param_Spec : Node_Id;
19825 Acc_Subprg : constant Node_Id :=
19826 Access_To_Subprogram_Definition (Acc_Def);
19829 if No (Acc_Subprg) then
19830 return Designates_T (Subtype_Mark (Acc_Def));
19833 -- Component is an access_to_subprogram: examine its formals,
19834 -- and result definition in the case of an access_to_function.
19836 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
19837 while Present (Param_Spec) loop
19838 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
19839 and then Mentions_T (Parameter_Type (Param_Spec))
19843 elsif Designates_T (Parameter_Type (Param_Spec)) then
19850 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
19851 if Nkind (Result_Definition (Acc_Subprg)) =
19852 N_Access_Definition
19854 return Mentions_T (Result_Definition (Acc_Subprg));
19856 return Designates_T (Result_Definition (Acc_Subprg));
19863 -- Start of processing for Check_Anonymous_Access_Components
19866 if No (Comp_List) then
19870 Comp := First (Component_Items (Comp_List));
19871 while Present (Comp) loop
19872 if Nkind (Comp) = N_Component_Declaration
19874 (Access_Definition (Component_Definition (Comp)))
19876 Mentions_T (Access_Definition (Component_Definition (Comp)))
19878 Comp_Def := Component_Definition (Comp);
19880 Access_To_Subprogram_Definition
19881 (Access_Definition (Comp_Def));
19883 Build_Incomplete_Type_Declaration;
19884 Anon_Access := Make_Temporary (Loc, 'S');
19886 -- Create a declaration for the anonymous access type: either
19887 -- an access_to_object or an access_to_subprogram.
19889 if Present (Acc_Def) then
19890 if Nkind (Acc_Def) = N_Access_Function_Definition then
19892 Make_Access_Function_Definition (Loc,
19893 Parameter_Specifications =>
19894 Parameter_Specifications (Acc_Def),
19895 Result_Definition => Result_Definition (Acc_Def));
19898 Make_Access_Procedure_Definition (Loc,
19899 Parameter_Specifications =>
19900 Parameter_Specifications (Acc_Def));
19905 Make_Access_To_Object_Definition (Loc,
19906 Subtype_Indication =>
19909 (Access_Definition (Comp_Def))));
19911 Set_Constant_Present
19912 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
19914 (Type_Def, All_Present (Access_Definition (Comp_Def)));
19917 Set_Null_Exclusion_Present
19919 Null_Exclusion_Present (Access_Definition (Comp_Def)));
19922 Make_Full_Type_Declaration (Loc,
19923 Defining_Identifier => Anon_Access,
19924 Type_Definition => Type_Def);
19926 Insert_Before (Typ_Decl, Decl);
19929 -- If an access to subprogram, create the extra formals
19931 if Present (Acc_Def) then
19932 Create_Extra_Formals (Designated_Type (Anon_Access));
19934 -- If an access to object, preserve entity of designated type,
19935 -- for ASIS use, before rewriting the component definition.
19942 Desig := Entity (Subtype_Indication (Type_Def));
19944 -- If the access definition is to the current record,
19945 -- the visible entity at this point is an incomplete
19946 -- type. Retrieve the full view to simplify ASIS queries
19948 if Ekind (Desig) = E_Incomplete_Type then
19949 Desig := Full_View (Desig);
19953 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
19958 Make_Component_Definition (Loc,
19959 Subtype_Indication =>
19960 New_Occurrence_Of (Anon_Access, Loc)));
19962 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
19963 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
19965 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
19968 Set_Is_Local_Anonymous_Access (Anon_Access);
19974 if Present (Variant_Part (Comp_List)) then
19978 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
19979 while Present (V) loop
19980 Check_Anonymous_Access_Components
19981 (Typ_Decl, Typ, Prev, Component_List (V));
19982 Next_Non_Pragma (V);
19986 end Check_Anonymous_Access_Components;
19988 ----------------------------------
19989 -- Preanalyze_Assert_Expression --
19990 ----------------------------------
19992 procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id) is
19994 In_Assertion_Expr := In_Assertion_Expr + 1;
19995 Preanalyze_Spec_Expression (N, T);
19996 In_Assertion_Expr := In_Assertion_Expr - 1;
19997 end Preanalyze_Assert_Expression;
19999 --------------------------------
20000 -- Preanalyze_Spec_Expression --
20001 --------------------------------
20003 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
20004 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
20006 In_Spec_Expression := True;
20007 Preanalyze_And_Resolve (N, T);
20008 In_Spec_Expression := Save_In_Spec_Expression;
20009 end Preanalyze_Spec_Expression;
20011 -----------------------------
20012 -- Record_Type_Declaration --
20013 -----------------------------
20015 procedure Record_Type_Declaration
20020 Def : constant Node_Id := Type_Definition (N);
20021 Is_Tagged : Boolean;
20022 Tag_Comp : Entity_Id;
20025 -- These flags must be initialized before calling Process_Discriminants
20026 -- because this routine makes use of them.
20028 Set_Ekind (T, E_Record_Type);
20030 Init_Size_Align (T);
20031 Set_Interfaces (T, No_Elist);
20032 Set_Stored_Constraint (T, No_Elist);
20036 if Ada_Version < Ada_2005
20037 or else not Interface_Present (Def)
20039 if Limited_Present (Def) then
20040 Check_SPARK_Restriction ("limited is not allowed", N);
20043 if Abstract_Present (Def) then
20044 Check_SPARK_Restriction ("abstract is not allowed", N);
20047 -- The flag Is_Tagged_Type might have already been set by
20048 -- Find_Type_Name if it detected an error for declaration T. This
20049 -- arises in the case of private tagged types where the full view
20050 -- omits the word tagged.
20053 Tagged_Present (Def)
20054 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
20056 Set_Is_Tagged_Type (T, Is_Tagged);
20057 Set_Is_Limited_Record (T, Limited_Present (Def));
20059 -- Type is abstract if full declaration carries keyword, or if
20060 -- previous partial view did.
20062 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
20063 or else Abstract_Present (Def));
20066 Check_SPARK_Restriction ("interface is not allowed", N);
20069 Analyze_Interface_Declaration (T, Def);
20071 if Present (Discriminant_Specifications (N)) then
20073 ("interface types cannot have discriminants",
20074 Defining_Identifier
20075 (First (Discriminant_Specifications (N))));
20079 -- First pass: if there are self-referential access components,
20080 -- create the required anonymous access type declarations, and if
20081 -- need be an incomplete type declaration for T itself.
20083 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
20085 if Ada_Version >= Ada_2005
20086 and then Present (Interface_List (Def))
20088 Check_Interfaces (N, Def);
20091 Ifaces_List : Elist_Id;
20094 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
20095 -- already in the parents.
20099 Ifaces_List => Ifaces_List,
20100 Exclude_Parents => True);
20102 Set_Interfaces (T, Ifaces_List);
20106 -- Records constitute a scope for the component declarations within.
20107 -- The scope is created prior to the processing of these declarations.
20108 -- Discriminants are processed first, so that they are visible when
20109 -- processing the other components. The Ekind of the record type itself
20110 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
20112 -- Enter record scope
20116 -- If an incomplete or private type declaration was already given for
20117 -- the type, then this scope already exists, and the discriminants have
20118 -- been declared within. We must verify that the full declaration
20119 -- matches the incomplete one.
20121 Check_Or_Process_Discriminants (N, T, Prev);
20123 Set_Is_Constrained (T, not Has_Discriminants (T));
20124 Set_Has_Delayed_Freeze (T, True);
20126 -- For tagged types add a manually analyzed component corresponding
20127 -- to the component _tag, the corresponding piece of tree will be
20128 -- expanded as part of the freezing actions if it is not a CPP_Class.
20132 -- Do not add the tag unless we are in expansion mode
20134 if Expander_Active then
20135 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
20136 Enter_Name (Tag_Comp);
20138 Set_Ekind (Tag_Comp, E_Component);
20139 Set_Is_Tag (Tag_Comp);
20140 Set_Is_Aliased (Tag_Comp);
20141 Set_Etype (Tag_Comp, RTE (RE_Tag));
20142 Set_DT_Entry_Count (Tag_Comp, No_Uint);
20143 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
20144 Init_Component_Location (Tag_Comp);
20146 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
20147 -- implemented interfaces.
20149 if Has_Interfaces (T) then
20150 Add_Interface_Tag_Components (N, T);
20154 Make_Class_Wide_Type (T);
20155 Set_Direct_Primitive_Operations (T, New_Elmt_List);
20158 -- We must suppress range checks when processing record components in
20159 -- the presence of discriminants, since we don't want spurious checks to
20160 -- be generated during their analysis, but Suppress_Range_Checks flags
20161 -- must be reset the after processing the record definition.
20163 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
20164 -- couldn't we just use the normal range check suppression method here.
20165 -- That would seem cleaner ???
20167 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
20168 Set_Kill_Range_Checks (T, True);
20169 Record_Type_Definition (Def, Prev);
20170 Set_Kill_Range_Checks (T, False);
20172 Record_Type_Definition (Def, Prev);
20175 -- Exit from record scope
20179 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
20180 -- the implemented interfaces and associate them an aliased entity.
20183 and then not Is_Empty_List (Interface_List (Def))
20185 Derive_Progenitor_Subprograms (T, T);
20188 Check_Function_Writable_Actuals (N);
20189 end Record_Type_Declaration;
20191 ----------------------------
20192 -- Record_Type_Definition --
20193 ----------------------------
20195 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
20196 Component : Entity_Id;
20197 Ctrl_Components : Boolean := False;
20198 Final_Storage_Only : Boolean;
20202 if Ekind (Prev_T) = E_Incomplete_Type then
20203 T := Full_View (Prev_T);
20208 -- In SPARK, tagged types and type extensions may only be declared in
20209 -- the specification of library unit packages.
20211 if Present (Def) and then Is_Tagged_Type (T) then
20217 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
20218 Typ := Parent (Def);
20221 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
20222 Typ := Parent (Parent (Def));
20225 Ctxt := Parent (Typ);
20227 if Nkind (Ctxt) = N_Package_Body
20228 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
20230 Check_SPARK_Restriction
20231 ("type should be defined in package specification", Typ);
20233 elsif Nkind (Ctxt) /= N_Package_Specification
20234 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
20236 Check_SPARK_Restriction
20237 ("type should be defined in library unit package", Typ);
20242 Final_Storage_Only := not Is_Controlled (T);
20244 -- Ada 2005: Check whether an explicit Limited is present in a derived
20245 -- type declaration.
20247 if Nkind (Parent (Def)) = N_Derived_Type_Definition
20248 and then Limited_Present (Parent (Def))
20250 Set_Is_Limited_Record (T);
20253 -- If the component list of a record type is defined by the reserved
20254 -- word null and there is no discriminant part, then the record type has
20255 -- no components and all records of the type are null records (RM 3.7)
20256 -- This procedure is also called to process the extension part of a
20257 -- record extension, in which case the current scope may have inherited
20261 or else No (Component_List (Def))
20262 or else Null_Present (Component_List (Def))
20264 if not Is_Tagged_Type (T) then
20265 Check_SPARK_Restriction ("non-tagged record cannot be null", Def);
20269 Analyze_Declarations (Component_Items (Component_List (Def)));
20271 if Present (Variant_Part (Component_List (Def))) then
20272 Check_SPARK_Restriction ("variant part is not allowed", Def);
20273 Analyze (Variant_Part (Component_List (Def)));
20277 -- After completing the semantic analysis of the record definition,
20278 -- record components, both new and inherited, are accessible. Set their
20279 -- kind accordingly. Exclude malformed itypes from illegal declarations,
20280 -- whose Ekind may be void.
20282 Component := First_Entity (Current_Scope);
20283 while Present (Component) loop
20284 if Ekind (Component) = E_Void
20285 and then not Is_Itype (Component)
20287 Set_Ekind (Component, E_Component);
20288 Init_Component_Location (Component);
20291 if Has_Task (Etype (Component)) then
20295 if Ekind (Component) /= E_Component then
20298 -- Do not set Has_Controlled_Component on a class-wide equivalent
20299 -- type. See Make_CW_Equivalent_Type.
20301 elsif not Is_Class_Wide_Equivalent_Type (T)
20302 and then (Has_Controlled_Component (Etype (Component))
20303 or else (Chars (Component) /= Name_uParent
20304 and then Is_Controlled (Etype (Component))))
20306 Set_Has_Controlled_Component (T, True);
20307 Final_Storage_Only :=
20309 and then Finalize_Storage_Only (Etype (Component));
20310 Ctrl_Components := True;
20313 Next_Entity (Component);
20316 -- A Type is Finalize_Storage_Only only if all its controlled components
20319 if Ctrl_Components then
20320 Set_Finalize_Storage_Only (T, Final_Storage_Only);
20323 -- Place reference to end record on the proper entity, which may
20324 -- be a partial view.
20326 if Present (Def) then
20327 Process_End_Label (Def, 'e', Prev_T);
20329 end Record_Type_Definition;
20331 ------------------------
20332 -- Replace_Components --
20333 ------------------------
20335 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
20336 function Process (N : Node_Id) return Traverse_Result;
20342 function Process (N : Node_Id) return Traverse_Result is
20346 if Nkind (N) = N_Discriminant_Specification then
20347 Comp := First_Discriminant (Typ);
20348 while Present (Comp) loop
20349 if Chars (Comp) = Chars (Defining_Identifier (N)) then
20350 Set_Defining_Identifier (N, Comp);
20354 Next_Discriminant (Comp);
20357 elsif Nkind (N) = N_Component_Declaration then
20358 Comp := First_Component (Typ);
20359 while Present (Comp) loop
20360 if Chars (Comp) = Chars (Defining_Identifier (N)) then
20361 Set_Defining_Identifier (N, Comp);
20365 Next_Component (Comp);
20372 procedure Replace is new Traverse_Proc (Process);
20374 -- Start of processing for Replace_Components
20378 end Replace_Components;
20380 -------------------------------
20381 -- Set_Completion_Referenced --
20382 -------------------------------
20384 procedure Set_Completion_Referenced (E : Entity_Id) is
20386 -- If in main unit, mark entity that is a completion as referenced,
20387 -- warnings go on the partial view when needed.
20389 if In_Extended_Main_Source_Unit (E) then
20390 Set_Referenced (E);
20392 end Set_Completion_Referenced;
20394 ---------------------
20395 -- Set_Fixed_Range --
20396 ---------------------
20398 -- The range for fixed-point types is complicated by the fact that we
20399 -- do not know the exact end points at the time of the declaration. This
20400 -- is true for three reasons:
20402 -- A size clause may affect the fudging of the end-points.
20403 -- A small clause may affect the values of the end-points.
20404 -- We try to include the end-points if it does not affect the size.
20406 -- This means that the actual end-points must be established at the
20407 -- point when the type is frozen. Meanwhile, we first narrow the range
20408 -- as permitted (so that it will fit if necessary in a small specified
20409 -- size), and then build a range subtree with these narrowed bounds.
20410 -- Set_Fixed_Range constructs the range from real literal values, and
20411 -- sets the range as the Scalar_Range of the given fixed-point type entity.
20413 -- The parent of this range is set to point to the entity so that it is
20414 -- properly hooked into the tree (unlike normal Scalar_Range entries for
20415 -- other scalar types, which are just pointers to the range in the
20416 -- original tree, this would otherwise be an orphan).
20418 -- The tree is left unanalyzed. When the type is frozen, the processing
20419 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
20420 -- analyzed, and uses this as an indication that it should complete
20421 -- work on the range (it will know the final small and size values).
20423 procedure Set_Fixed_Range
20429 S : constant Node_Id :=
20431 Low_Bound => Make_Real_Literal (Loc, Lo),
20432 High_Bound => Make_Real_Literal (Loc, Hi));
20434 Set_Scalar_Range (E, S);
20437 -- Before the freeze point, the bounds of a fixed point are universal
20438 -- and carry the corresponding type.
20440 Set_Etype (Low_Bound (S), Universal_Real);
20441 Set_Etype (High_Bound (S), Universal_Real);
20442 end Set_Fixed_Range;
20444 ----------------------------------
20445 -- Set_Scalar_Range_For_Subtype --
20446 ----------------------------------
20448 procedure Set_Scalar_Range_For_Subtype
20449 (Def_Id : Entity_Id;
20453 Kind : constant Entity_Kind := Ekind (Def_Id);
20456 -- Defend against previous error
20458 if Nkind (R) = N_Error then
20462 Set_Scalar_Range (Def_Id, R);
20464 -- We need to link the range into the tree before resolving it so
20465 -- that types that are referenced, including importantly the subtype
20466 -- itself, are properly frozen (Freeze_Expression requires that the
20467 -- expression be properly linked into the tree). Of course if it is
20468 -- already linked in, then we do not disturb the current link.
20470 if No (Parent (R)) then
20471 Set_Parent (R, Def_Id);
20474 -- Reset the kind of the subtype during analysis of the range, to
20475 -- catch possible premature use in the bounds themselves.
20477 Set_Ekind (Def_Id, E_Void);
20478 Process_Range_Expr_In_Decl (R, Subt);
20479 Set_Ekind (Def_Id, Kind);
20480 end Set_Scalar_Range_For_Subtype;
20482 --------------------------------------------------------
20483 -- Set_Stored_Constraint_From_Discriminant_Constraint --
20484 --------------------------------------------------------
20486 procedure Set_Stored_Constraint_From_Discriminant_Constraint
20490 -- Make sure set if encountered during Expand_To_Stored_Constraint
20492 Set_Stored_Constraint (E, No_Elist);
20494 -- Give it the right value
20496 if Is_Constrained (E) and then Has_Discriminants (E) then
20497 Set_Stored_Constraint (E,
20498 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
20500 end Set_Stored_Constraint_From_Discriminant_Constraint;
20502 -------------------------------------
20503 -- Signed_Integer_Type_Declaration --
20504 -------------------------------------
20506 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
20507 Implicit_Base : Entity_Id;
20508 Base_Typ : Entity_Id;
20511 Errs : Boolean := False;
20515 function Can_Derive_From (E : Entity_Id) return Boolean;
20516 -- Determine whether given bounds allow derivation from specified type
20518 procedure Check_Bound (Expr : Node_Id);
20519 -- Check bound to make sure it is integral and static. If not, post
20520 -- appropriate error message and set Errs flag
20522 ---------------------
20523 -- Can_Derive_From --
20524 ---------------------
20526 -- Note we check both bounds against both end values, to deal with
20527 -- strange types like ones with a range of 0 .. -12341234.
20529 function Can_Derive_From (E : Entity_Id) return Boolean is
20530 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
20531 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
20533 return Lo <= Lo_Val and then Lo_Val <= Hi
20535 Lo <= Hi_Val and then Hi_Val <= Hi;
20536 end Can_Derive_From;
20542 procedure Check_Bound (Expr : Node_Id) is
20544 -- If a range constraint is used as an integer type definition, each
20545 -- bound of the range must be defined by a static expression of some
20546 -- integer type, but the two bounds need not have the same integer
20547 -- type (Negative bounds are allowed.) (RM 3.5.4)
20549 if not Is_Integer_Type (Etype (Expr)) then
20551 ("integer type definition bounds must be of integer type", Expr);
20554 elsif not Is_OK_Static_Expression (Expr) then
20555 Flag_Non_Static_Expr
20556 ("non-static expression used for integer type bound!", Expr);
20559 -- The bounds are folded into literals, and we set their type to be
20560 -- universal, to avoid typing difficulties: we cannot set the type
20561 -- of the literal to the new type, because this would be a forward
20562 -- reference for the back end, and if the original type is user-
20563 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
20566 if Is_Entity_Name (Expr) then
20567 Fold_Uint (Expr, Expr_Value (Expr), True);
20570 Set_Etype (Expr, Universal_Integer);
20574 -- Start of processing for Signed_Integer_Type_Declaration
20577 -- Create an anonymous base type
20580 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
20582 -- Analyze and check the bounds, they can be of any integer type
20584 Lo := Low_Bound (Def);
20585 Hi := High_Bound (Def);
20587 -- Arbitrarily use Integer as the type if either bound had an error
20589 if Hi = Error or else Lo = Error then
20590 Base_Typ := Any_Integer;
20591 Set_Error_Posted (T, True);
20593 -- Here both bounds are OK expressions
20596 Analyze_And_Resolve (Lo, Any_Integer);
20597 Analyze_And_Resolve (Hi, Any_Integer);
20603 Hi := Type_High_Bound (Standard_Long_Long_Integer);
20604 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
20607 -- Find type to derive from
20609 Lo_Val := Expr_Value (Lo);
20610 Hi_Val := Expr_Value (Hi);
20612 if Can_Derive_From (Standard_Short_Short_Integer) then
20613 Base_Typ := Base_Type (Standard_Short_Short_Integer);
20615 elsif Can_Derive_From (Standard_Short_Integer) then
20616 Base_Typ := Base_Type (Standard_Short_Integer);
20618 elsif Can_Derive_From (Standard_Integer) then
20619 Base_Typ := Base_Type (Standard_Integer);
20621 elsif Can_Derive_From (Standard_Long_Integer) then
20622 Base_Typ := Base_Type (Standard_Long_Integer);
20624 elsif Can_Derive_From (Standard_Long_Long_Integer) then
20625 Base_Typ := Base_Type (Standard_Long_Long_Integer);
20628 Base_Typ := Base_Type (Standard_Long_Long_Integer);
20629 Error_Msg_N ("integer type definition bounds out of range", Def);
20630 Hi := Type_High_Bound (Standard_Long_Long_Integer);
20631 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
20635 -- Complete both implicit base and declared first subtype entities
20637 Set_Etype (Implicit_Base, Base_Typ);
20638 Set_Size_Info (Implicit_Base, (Base_Typ));
20639 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
20640 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
20642 Set_Ekind (T, E_Signed_Integer_Subtype);
20643 Set_Etype (T, Implicit_Base);
20645 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
20647 Set_Size_Info (T, (Implicit_Base));
20648 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
20649 Set_Scalar_Range (T, Def);
20650 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
20651 Set_Is_Constrained (T);
20652 end Signed_Integer_Type_Declaration;