1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2011, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Checks; use Checks;
28 with Debug; use Debug;
29 with Elists; use Elists;
30 with Einfo; use Einfo;
31 with Errout; use Errout;
32 with Eval_Fat; use Eval_Fat;
33 with Exp_Ch3; use Exp_Ch3;
34 with Exp_Ch9; use Exp_Ch9;
35 with Exp_Disp; use Exp_Disp;
36 with Exp_Dist; use Exp_Dist;
37 with Exp_Tss; use Exp_Tss;
38 with Exp_Util; use Exp_Util;
39 with Fname; use Fname;
40 with Freeze; use Freeze;
41 with Itypes; use Itypes;
42 with Layout; use Layout;
44 with Lib.Xref; use Lib.Xref;
45 with Namet; use Namet;
46 with Nmake; use Nmake;
48 with Restrict; use Restrict;
49 with Rident; use Rident;
50 with Rtsfind; use Rtsfind;
52 with Sem_Aux; use Sem_Aux;
53 with Sem_Case; use Sem_Case;
54 with Sem_Cat; use Sem_Cat;
55 with Sem_Ch6; use Sem_Ch6;
56 with Sem_Ch7; use Sem_Ch7;
57 with Sem_Ch8; use Sem_Ch8;
58 with Sem_Ch13; use Sem_Ch13;
59 with Sem_Disp; use Sem_Disp;
60 with Sem_Dist; use Sem_Dist;
61 with Sem_Elim; use Sem_Elim;
62 with Sem_Eval; use Sem_Eval;
63 with Sem_Mech; use Sem_Mech;
64 with Sem_Prag; use Sem_Prag;
65 with Sem_Res; use Sem_Res;
66 with Sem_Smem; use Sem_Smem;
67 with Sem_Type; use Sem_Type;
68 with Sem_Util; use Sem_Util;
69 with Sem_Warn; use Sem_Warn;
70 with Stand; use Stand;
71 with Sinfo; use Sinfo;
72 with Sinput; use Sinput;
73 with Snames; use Snames;
74 with Targparm; use Targparm;
75 with Tbuild; use Tbuild;
76 with Ttypes; use Ttypes;
77 with Uintp; use Uintp;
78 with Urealp; use Urealp;
80 package body Sem_Ch3 is
82 -----------------------
83 -- Local Subprograms --
84 -----------------------
86 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
87 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
88 -- abstract interface types implemented by a record type or a derived
91 procedure Build_Derived_Type
93 Parent_Type : Entity_Id;
94 Derived_Type : Entity_Id;
95 Is_Completion : Boolean;
96 Derive_Subps : Boolean := True);
97 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
98 -- the N_Full_Type_Declaration node containing the derived type definition.
99 -- Parent_Type is the entity for the parent type in the derived type
100 -- definition and Derived_Type the actual derived type. Is_Completion must
101 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
102 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
103 -- completion of a private type declaration. If Is_Completion is set to
104 -- True, N is the completion of a private type declaration and Derived_Type
105 -- is different from the defining identifier inside N (i.e. Derived_Type /=
106 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
107 -- subprograms should be derived. The only case where this parameter is
108 -- False is when Build_Derived_Type is recursively called to process an
109 -- implicit derived full type for a type derived from a private type (in
110 -- that case the subprograms must only be derived for the private view of
113 -- ??? These flags need a bit of re-examination and re-documentation:
114 -- ??? are they both necessary (both seem related to the recursion)?
116 procedure Build_Derived_Access_Type
118 Parent_Type : Entity_Id;
119 Derived_Type : Entity_Id);
120 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
121 -- create an implicit base if the parent type is constrained or if the
122 -- subtype indication has a constraint.
124 procedure Build_Derived_Array_Type
126 Parent_Type : Entity_Id;
127 Derived_Type : Entity_Id);
128 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
129 -- create an implicit base if the parent type is constrained or if the
130 -- subtype indication has a constraint.
132 procedure Build_Derived_Concurrent_Type
134 Parent_Type : Entity_Id;
135 Derived_Type : Entity_Id);
136 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
137 -- protected type, inherit entries and protected subprograms, check
138 -- legality of discriminant constraints if any.
140 procedure Build_Derived_Enumeration_Type
142 Parent_Type : Entity_Id;
143 Derived_Type : Entity_Id);
144 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
145 -- type, we must create a new list of literals. Types derived from
146 -- Character and [Wide_]Wide_Character are special-cased.
148 procedure Build_Derived_Numeric_Type
150 Parent_Type : Entity_Id;
151 Derived_Type : Entity_Id);
152 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
153 -- an anonymous base type, and propagate constraint to subtype if needed.
155 procedure Build_Derived_Private_Type
157 Parent_Type : Entity_Id;
158 Derived_Type : Entity_Id;
159 Is_Completion : Boolean;
160 Derive_Subps : Boolean := True);
161 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
162 -- because the parent may or may not have a completion, and the derivation
163 -- may itself be a completion.
165 procedure Build_Derived_Record_Type
167 Parent_Type : Entity_Id;
168 Derived_Type : Entity_Id;
169 Derive_Subps : Boolean := True);
170 -- Subsidiary procedure for Build_Derived_Type and
171 -- Analyze_Private_Extension_Declaration used for tagged and untagged
172 -- record types. All parameters are as in Build_Derived_Type except that
173 -- N, in addition to being an N_Full_Type_Declaration node, can also be an
174 -- N_Private_Extension_Declaration node. See the definition of this routine
175 -- for much more info. Derive_Subps indicates whether subprograms should
176 -- be derived from the parent type. The only case where Derive_Subps is
177 -- False is for an implicit derived full type for a type derived from a
178 -- private type (see Build_Derived_Type).
180 procedure Build_Discriminal (Discrim : Entity_Id);
181 -- Create the discriminal corresponding to discriminant Discrim, that is
182 -- the parameter corresponding to Discrim to be used in initialization
183 -- procedures for the type where Discrim is a discriminant. Discriminals
184 -- are not used during semantic analysis, and are not fully defined
185 -- entities until expansion. Thus they are not given a scope until
186 -- initialization procedures are built.
188 function Build_Discriminant_Constraints
191 Derived_Def : Boolean := False) return Elist_Id;
192 -- Validate discriminant constraints and return the list of the constraints
193 -- in order of discriminant declarations, where T is the discriminated
194 -- unconstrained type. Def is the N_Subtype_Indication node where the
195 -- discriminants constraints for T are specified. Derived_Def is True
196 -- when building the discriminant constraints in a derived type definition
197 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
198 -- type and Def is the constraint "(xxx)" on T and this routine sets the
199 -- Corresponding_Discriminant field of the discriminants in the derived
200 -- type D to point to the corresponding discriminants in the parent type T.
202 procedure Build_Discriminated_Subtype
206 Related_Nod : Node_Id;
207 For_Access : Boolean := False);
208 -- Subsidiary procedure to Constrain_Discriminated_Type and to
209 -- Process_Incomplete_Dependents. Given
211 -- T (a possibly discriminated base type)
212 -- Def_Id (a very partially built subtype for T),
214 -- the call completes Def_Id to be the appropriate E_*_Subtype.
216 -- The Elist is the list of discriminant constraints if any (it is set
217 -- to No_Elist if T is not a discriminated type, and to an empty list if
218 -- T has discriminants but there are no discriminant constraints). The
219 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
220 -- The For_Access says whether or not this subtype is really constraining
221 -- an access type. That is its sole purpose is the designated type of an
222 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
223 -- is built to avoid freezing T when the access subtype is frozen.
225 function Build_Scalar_Bound
228 Der_T : Entity_Id) return Node_Id;
229 -- The bounds of a derived scalar type are conversions of the bounds of
230 -- the parent type. Optimize the representation if the bounds are literals.
231 -- Needs a more complete spec--what are the parameters exactly, and what
232 -- exactly is the returned value, and how is Bound affected???
234 procedure Build_Underlying_Full_View
238 -- If the completion of a private type is itself derived from a private
239 -- type, or if the full view of a private subtype is itself private, the
240 -- back-end has no way to compute the actual size of this type. We build
241 -- an internal subtype declaration of the proper parent type to convey
242 -- this information. This extra mechanism is needed because a full
243 -- view cannot itself have a full view (it would get clobbered during
246 procedure Check_Access_Discriminant_Requires_Limited
249 -- Check the restriction that the type to which an access discriminant
250 -- belongs must be a concurrent type or a descendant of a type with
251 -- the reserved word 'limited' in its declaration.
253 procedure Check_Anonymous_Access_Components
257 Comp_List : Node_Id);
258 -- Ada 2005 AI-382: an access component in a record definition can refer to
259 -- the enclosing record, in which case it denotes the type itself, and not
260 -- the current instance of the type. We create an anonymous access type for
261 -- the component, and flag it as an access to a component, so accessibility
262 -- checks are properly performed on it. The declaration of the access type
263 -- is placed ahead of that of the record to prevent order-of-elaboration
264 -- circularity issues in Gigi. We create an incomplete type for the record
265 -- declaration, which is the designated type of the anonymous access.
267 procedure Check_Delta_Expression (E : Node_Id);
268 -- Check that the expression represented by E is suitable for use as a
269 -- delta expression, i.e. it is of real type and is static.
271 procedure Check_Digits_Expression (E : Node_Id);
272 -- Check that the expression represented by E is suitable for use as a
273 -- digits expression, i.e. it is of integer type, positive and static.
275 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
276 -- Validate the initialization of an object declaration. T is the required
277 -- type, and Exp is the initialization expression.
279 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
280 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
282 procedure Check_Or_Process_Discriminants
285 Prev : Entity_Id := Empty);
286 -- If N is the full declaration of the completion T of an incomplete or
287 -- private type, check its discriminants (which are already known to be
288 -- conformant with those of the partial view, see Find_Type_Name),
289 -- otherwise process them. Prev is the entity of the partial declaration,
292 procedure Check_Real_Bound (Bound : Node_Id);
293 -- Check given bound for being of real type and static. If not, post an
294 -- appropriate message, and rewrite the bound with the real literal zero.
296 procedure Constant_Redeclaration
300 -- Various checks on legality of full declaration of deferred constant.
301 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
302 -- node. The caller has not yet set any attributes of this entity.
304 function Contain_Interface
306 Ifaces : Elist_Id) return Boolean;
307 -- Ada 2005: Determine whether Iface is present in the list Ifaces
309 procedure Convert_Scalar_Bounds
311 Parent_Type : Entity_Id;
312 Derived_Type : Entity_Id;
314 -- For derived scalar types, convert the bounds in the type definition to
315 -- the derived type, and complete their analysis. Given a constraint of the
316 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
317 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
318 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
319 -- subtype are conversions of those bounds to the derived_type, so that
320 -- their typing is consistent.
322 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
323 -- Copies attributes from array base type T2 to array base type T1. Copies
324 -- only attributes that apply to base types, but not subtypes.
326 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
327 -- Copies attributes from array subtype T2 to array subtype T1. Copies
328 -- attributes that apply to both subtypes and base types.
330 procedure Create_Constrained_Components
334 Constraints : Elist_Id);
335 -- Build the list of entities for a constrained discriminated record
336 -- subtype. If a component depends on a discriminant, replace its subtype
337 -- using the discriminant values in the discriminant constraint. Subt
338 -- is the defining identifier for the subtype whose list of constrained
339 -- entities we will create. Decl_Node is the type declaration node where
340 -- we will attach all the itypes created. Typ is the base discriminated
341 -- type for the subtype Subt. Constraints is the list of discriminant
342 -- constraints for Typ.
344 function Constrain_Component_Type
346 Constrained_Typ : Entity_Id;
347 Related_Node : Node_Id;
349 Constraints : Elist_Id) return Entity_Id;
350 -- Given a discriminated base type Typ, a list of discriminant constraint
351 -- Constraints for Typ and a component of Typ, with type Compon_Type,
352 -- create and return the type corresponding to Compon_type where all
353 -- discriminant references are replaced with the corresponding constraint.
354 -- If no discriminant references occur in Compon_Typ then return it as is.
355 -- Constrained_Typ is the final constrained subtype to which the
356 -- constrained Compon_Type belongs. Related_Node is the node where we will
357 -- attach all the itypes created.
359 -- Above description is confused, what is Compon_Type???
361 procedure Constrain_Access
362 (Def_Id : in out Entity_Id;
364 Related_Nod : Node_Id);
365 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
366 -- an anonymous type created for a subtype indication. In that case it is
367 -- created in the procedure and attached to Related_Nod.
369 procedure Constrain_Array
370 (Def_Id : in out Entity_Id;
372 Related_Nod : Node_Id;
373 Related_Id : Entity_Id;
375 -- Apply a list of index constraints to an unconstrained array type. The
376 -- first parameter is the entity for the resulting subtype. A value of
377 -- Empty for Def_Id indicates that an implicit type must be created, but
378 -- creation is delayed (and must be done by this procedure) because other
379 -- subsidiary implicit types must be created first (which is why Def_Id
380 -- is an in/out parameter). The second parameter is a subtype indication
381 -- node for the constrained array to be created (e.g. something of the
382 -- form string (1 .. 10)). Related_Nod gives the place where this type
383 -- has to be inserted in the tree. The Related_Id and Suffix parameters
384 -- are used to build the associated Implicit type name.
386 procedure Constrain_Concurrent
387 (Def_Id : in out Entity_Id;
389 Related_Nod : Node_Id;
390 Related_Id : Entity_Id;
392 -- Apply list of discriminant constraints to an unconstrained concurrent
395 -- SI is the N_Subtype_Indication node containing the constraint and
396 -- the unconstrained type to constrain.
398 -- Def_Id is the entity for the resulting constrained subtype. A value
399 -- of Empty for Def_Id indicates that an implicit type must be created,
400 -- but creation is delayed (and must be done by this procedure) because
401 -- other subsidiary implicit types must be created first (which is why
402 -- Def_Id is an in/out parameter).
404 -- Related_Nod gives the place where this type has to be inserted
407 -- The last two arguments are used to create its external name if needed.
409 function Constrain_Corresponding_Record
410 (Prot_Subt : Entity_Id;
411 Corr_Rec : Entity_Id;
412 Related_Nod : Node_Id;
413 Related_Id : Entity_Id) return Entity_Id;
414 -- When constraining a protected type or task type with discriminants,
415 -- constrain the corresponding record with the same discriminant values.
417 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
418 -- Constrain a decimal fixed point type with a digits constraint and/or a
419 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
421 procedure Constrain_Discriminated_Type
424 Related_Nod : Node_Id;
425 For_Access : Boolean := False);
426 -- Process discriminant constraints of composite type. Verify that values
427 -- have been provided for all discriminants, that the original type is
428 -- unconstrained, and that the types of the supplied expressions match
429 -- the discriminant types. The first three parameters are like in routine
430 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
433 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
434 -- Constrain an enumeration type with a range constraint. This is identical
435 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
437 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
438 -- Constrain a floating point type with either a digits constraint
439 -- and/or a range constraint, building a E_Floating_Point_Subtype.
441 procedure Constrain_Index
444 Related_Nod : Node_Id;
445 Related_Id : Entity_Id;
448 -- Process an index constraint S in a constrained array declaration. The
449 -- constraint can be a subtype name, or a range with or without an explicit
450 -- subtype mark. The index is the corresponding index of the unconstrained
451 -- array. The Related_Id and Suffix parameters are used to build the
452 -- associated Implicit type name.
454 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
455 -- Build subtype of a signed or modular integer type
457 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
458 -- Constrain an ordinary fixed point type with a range constraint, and
459 -- build an E_Ordinary_Fixed_Point_Subtype entity.
461 procedure Copy_And_Swap (Priv, Full : Entity_Id);
462 -- Copy the Priv entity into the entity of its full declaration then swap
463 -- the two entities in such a manner that the former private type is now
464 -- seen as a full type.
466 procedure Decimal_Fixed_Point_Type_Declaration
469 -- Create a new decimal fixed point type, and apply the constraint to
470 -- obtain a subtype of this new type.
472 procedure Complete_Private_Subtype
475 Full_Base : Entity_Id;
476 Related_Nod : Node_Id);
477 -- Complete the implicit full view of a private subtype by setting the
478 -- appropriate semantic fields. If the full view of the parent is a record
479 -- type, build constrained components of subtype.
481 procedure Derive_Progenitor_Subprograms
482 (Parent_Type : Entity_Id;
483 Tagged_Type : Entity_Id);
484 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
485 -- operations of progenitors of Tagged_Type, and replace the subsidiary
486 -- subtypes with Tagged_Type, to build the specs of the inherited interface
487 -- primitives. The derived primitives are aliased to those of the
488 -- interface. This routine takes care also of transferring to the full view
489 -- subprograms associated with the partial view of Tagged_Type that cover
490 -- interface primitives.
492 procedure Derived_Standard_Character
494 Parent_Type : Entity_Id;
495 Derived_Type : Entity_Id);
496 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
497 -- derivations from types Standard.Character and Standard.Wide_Character.
499 procedure Derived_Type_Declaration
502 Is_Completion : Boolean);
503 -- Process a derived type declaration. Build_Derived_Type is invoked
504 -- to process the actual derived type definition. Parameters N and
505 -- Is_Completion have the same meaning as in Build_Derived_Type.
506 -- T is the N_Defining_Identifier for the entity defined in the
507 -- N_Full_Type_Declaration node N, that is T is the derived type.
509 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
510 -- Insert each literal in symbol table, as an overloadable identifier. Each
511 -- enumeration type is mapped into a sequence of integers, and each literal
512 -- is defined as a constant with integer value. If any of the literals are
513 -- character literals, the type is a character type, which means that
514 -- strings are legal aggregates for arrays of components of the type.
516 function Expand_To_Stored_Constraint
518 Constraint : Elist_Id) return Elist_Id;
519 -- Given a constraint (i.e. a list of expressions) on the discriminants of
520 -- Typ, expand it into a constraint on the stored discriminants and return
521 -- the new list of expressions constraining the stored discriminants.
523 function Find_Type_Of_Object
525 Related_Nod : Node_Id) return Entity_Id;
526 -- Get type entity for object referenced by Obj_Def, attaching the
527 -- implicit types generated to Related_Nod
529 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
530 -- Create a new float and apply the constraint to obtain subtype of it
532 function Has_Range_Constraint (N : Node_Id) return Boolean;
533 -- Given an N_Subtype_Indication node N, return True if a range constraint
534 -- is present, either directly, or as part of a digits or delta constraint.
535 -- In addition, a digits constraint in the decimal case returns True, since
536 -- it establishes a default range if no explicit range is present.
538 function Inherit_Components
540 Parent_Base : Entity_Id;
541 Derived_Base : Entity_Id;
543 Inherit_Discr : Boolean;
544 Discs : Elist_Id) return Elist_Id;
545 -- Called from Build_Derived_Record_Type to inherit the components of
546 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
547 -- For more information on derived types and component inheritance please
548 -- consult the comment above the body of Build_Derived_Record_Type.
550 -- N is the original derived type declaration
552 -- Is_Tagged is set if we are dealing with tagged types
554 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
555 -- Parent_Base, otherwise no discriminants are inherited.
557 -- Discs gives the list of constraints that apply to Parent_Base in the
558 -- derived type declaration. If Discs is set to No_Elist, then we have
559 -- the following situation:
561 -- type Parent (D1..Dn : ..) is [tagged] record ...;
562 -- type Derived is new Parent [with ...];
564 -- which gets treated as
566 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
568 -- For untagged types the returned value is an association list. The list
569 -- starts from the association (Parent_Base => Derived_Base), and then it
570 -- contains a sequence of the associations of the form
572 -- (Old_Component => New_Component),
574 -- where Old_Component is the Entity_Id of a component in Parent_Base and
575 -- New_Component is the Entity_Id of the corresponding component in
576 -- Derived_Base. For untagged records, this association list is needed when
577 -- copying the record declaration for the derived base. In the tagged case
578 -- the value returned is irrelevant.
580 function Is_Valid_Constraint_Kind
582 Constraint_Kind : Node_Kind) return Boolean;
583 -- Returns True if it is legal to apply the given kind of constraint to the
584 -- given kind of type (index constraint to an array type, for example).
586 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
587 -- Create new modular type. Verify that modulus is in bounds
589 procedure New_Concatenation_Op (Typ : Entity_Id);
590 -- Create an abbreviated declaration for an operator in order to
591 -- materialize concatenation on array types.
593 procedure Ordinary_Fixed_Point_Type_Declaration
596 -- Create a new ordinary fixed point type, and apply the constraint to
597 -- obtain subtype of it.
599 procedure Prepare_Private_Subtype_Completion
601 Related_Nod : Node_Id);
602 -- Id is a subtype of some private type. Creates the full declaration
603 -- associated with Id whenever possible, i.e. when the full declaration
604 -- of the base type is already known. Records each subtype into
605 -- Private_Dependents of the base type.
607 procedure Process_Incomplete_Dependents
611 -- Process all entities that depend on an incomplete type. There include
612 -- subtypes, subprogram types that mention the incomplete type in their
613 -- profiles, and subprogram with access parameters that designate the
616 -- Inc_T is the defining identifier of an incomplete type declaration, its
617 -- Ekind is E_Incomplete_Type.
619 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
621 -- Full_T is N's defining identifier.
623 -- Subtypes of incomplete types with discriminants are completed when the
624 -- parent type is. This is simpler than private subtypes, because they can
625 -- only appear in the same scope, and there is no need to exchange views.
626 -- Similarly, access_to_subprogram types may have a parameter or a return
627 -- type that is an incomplete type, and that must be replaced with the
630 -- If the full type is tagged, subprogram with access parameters that
631 -- designated the incomplete may be primitive operations of the full type,
632 -- and have to be processed accordingly.
634 procedure Process_Real_Range_Specification (Def : Node_Id);
635 -- Given the type definition for a real type, this procedure processes and
636 -- checks the real range specification of this type definition if one is
637 -- present. If errors are found, error messages are posted, and the
638 -- Real_Range_Specification of Def is reset to Empty.
640 procedure Record_Type_Declaration
644 -- Process a record type declaration (for both untagged and tagged
645 -- records). Parameters T and N are exactly like in procedure
646 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
647 -- for this routine. If this is the completion of an incomplete type
648 -- declaration, Prev is the entity of the incomplete declaration, used for
649 -- cross-referencing. Otherwise Prev = T.
651 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
652 -- This routine is used to process the actual record type definition (both
653 -- for untagged and tagged records). Def is a record type definition node.
654 -- This procedure analyzes the components in this record type definition.
655 -- Prev_T is the entity for the enclosing record type. It is provided so
656 -- that its Has_Task flag can be set if any of the component have Has_Task
657 -- set. If the declaration is the completion of an incomplete type
658 -- declaration, Prev_T is the original incomplete type, whose full view is
661 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
662 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
663 -- build a copy of the declaration tree of the parent, and we create
664 -- independently the list of components for the derived type. Semantic
665 -- information uses the component entities, but record representation
666 -- clauses are validated on the declaration tree. This procedure replaces
667 -- discriminants and components in the declaration with those that have
668 -- been created by Inherit_Components.
670 procedure Set_Fixed_Range
675 -- Build a range node with the given bounds and set it as the Scalar_Range
676 -- of the given fixed-point type entity. Loc is the source location used
677 -- for the constructed range. See body for further details.
679 procedure Set_Scalar_Range_For_Subtype
683 -- This routine is used to set the scalar range field for a subtype given
684 -- Def_Id, the entity for the subtype, and R, the range expression for the
685 -- scalar range. Subt provides the parent subtype to be used to analyze,
686 -- resolve, and check the given range.
688 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
689 -- Create a new signed integer entity, and apply the constraint to obtain
690 -- the required first named subtype of this type.
692 procedure Set_Stored_Constraint_From_Discriminant_Constraint
694 -- E is some record type. This routine computes E's Stored_Constraint
695 -- from its Discriminant_Constraint.
697 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
698 -- Check that an entity in a list of progenitors is an interface,
699 -- emit error otherwise.
701 -----------------------
702 -- Access_Definition --
703 -----------------------
705 function Access_Definition
706 (Related_Nod : Node_Id;
707 N : Node_Id) return Entity_Id
709 Loc : constant Source_Ptr := Sloc (Related_Nod);
710 Anon_Type : Entity_Id;
711 Anon_Scope : Entity_Id;
712 Desig_Type : Entity_Id;
714 Enclosing_Prot_Type : Entity_Id := Empty;
717 Check_SPARK_Restriction ("access type is not allowed", N);
719 if Is_Entry (Current_Scope)
720 and then Is_Task_Type (Etype (Scope (Current_Scope)))
722 Error_Msg_N ("task entries cannot have access parameters", N);
726 -- Ada 2005: for an object declaration the corresponding anonymous
727 -- type is declared in the current scope.
729 -- If the access definition is the return type of another access to
730 -- function, scope is the current one, because it is the one of the
731 -- current type declaration.
733 if Nkind_In (Related_Nod, N_Object_Declaration,
734 N_Access_Function_Definition)
736 Anon_Scope := Current_Scope;
738 -- For the anonymous function result case, retrieve the scope of the
739 -- function specification's associated entity rather than using the
740 -- current scope. The current scope will be the function itself if the
741 -- formal part is currently being analyzed, but will be the parent scope
742 -- in the case of a parameterless function, and we always want to use
743 -- the function's parent scope. Finally, if the function is a child
744 -- unit, we must traverse the tree to retrieve the proper entity.
746 elsif Nkind (Related_Nod) = N_Function_Specification
747 and then Nkind (Parent (N)) /= N_Parameter_Specification
749 -- If the current scope is a protected type, the anonymous access
750 -- is associated with one of the protected operations, and must
751 -- be available in the scope that encloses the protected declaration.
752 -- Otherwise the type is in the scope enclosing the subprogram.
754 -- If the function has formals, The return type of a subprogram
755 -- declaration is analyzed in the scope of the subprogram (see
756 -- Process_Formals) and thus the protected type, if present, is
757 -- the scope of the current function scope.
759 if Ekind (Current_Scope) = E_Protected_Type then
760 Enclosing_Prot_Type := Current_Scope;
762 elsif Ekind (Current_Scope) = E_Function
763 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
765 Enclosing_Prot_Type := Scope (Current_Scope);
768 if Present (Enclosing_Prot_Type) then
769 Anon_Scope := Scope (Enclosing_Prot_Type);
772 Anon_Scope := Scope (Defining_Entity (Related_Nod));
776 -- For access formals, access components, and access discriminants,
777 -- the scope is that of the enclosing declaration,
779 Anon_Scope := Scope (Current_Scope);
784 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
787 and then Ada_Version >= Ada_2005
789 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
792 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
793 -- the corresponding semantic routine
795 if Present (Access_To_Subprogram_Definition (N)) then
796 Access_Subprogram_Declaration
797 (T_Name => Anon_Type,
798 T_Def => Access_To_Subprogram_Definition (N));
800 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
802 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
805 (Anon_Type, E_Anonymous_Access_Subprogram_Type);
808 Set_Can_Use_Internal_Rep
809 (Anon_Type, not Always_Compatible_Rep_On_Target);
811 -- If the anonymous access is associated with a protected operation
812 -- create a reference to it after the enclosing protected definition
813 -- because the itype will be used in the subsequent bodies.
815 if Ekind (Current_Scope) = E_Protected_Type then
816 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
822 Find_Type (Subtype_Mark (N));
823 Desig_Type := Entity (Subtype_Mark (N));
825 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
826 Set_Etype (Anon_Type, Anon_Type);
828 -- Make sure the anonymous access type has size and alignment fields
829 -- set, as required by gigi. This is necessary in the case of the
830 -- Task_Body_Procedure.
832 if not Has_Private_Component (Desig_Type) then
833 Layout_Type (Anon_Type);
836 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
837 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
838 -- the null value is allowed. In Ada 95 the null value is never allowed.
840 if Ada_Version >= Ada_2005 then
841 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
843 Set_Can_Never_Be_Null (Anon_Type, True);
846 -- The anonymous access type is as public as the discriminated type or
847 -- subprogram that defines it. It is imported (for back-end purposes)
848 -- if the designated type is.
850 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
852 -- Ada 2005 (AI-231): Propagate the access-constant attribute
854 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
856 -- The context is either a subprogram declaration, object declaration,
857 -- or an access discriminant, in a private or a full type declaration.
858 -- In the case of a subprogram, if the designated type is incomplete,
859 -- the operation will be a primitive operation of the full type, to be
860 -- updated subsequently. If the type is imported through a limited_with
861 -- clause, the subprogram is not a primitive operation of the type
862 -- (which is declared elsewhere in some other scope).
864 if Ekind (Desig_Type) = E_Incomplete_Type
865 and then not From_With_Type (Desig_Type)
866 and then Is_Overloadable (Current_Scope)
868 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
869 Set_Has_Delayed_Freeze (Current_Scope);
872 -- Ada 2005: if the designated type is an interface that may contain
873 -- tasks, create a Master entity for the declaration. This must be done
874 -- before expansion of the full declaration, because the declaration may
875 -- include an expression that is an allocator, whose expansion needs the
876 -- proper Master for the created tasks.
878 if Nkind (Related_Nod) = N_Object_Declaration
879 and then Expander_Active
881 if Is_Interface (Desig_Type)
882 and then Is_Limited_Record (Desig_Type)
884 Build_Class_Wide_Master (Anon_Type);
886 -- Similarly, if the type is an anonymous access that designates
887 -- tasks, create a master entity for it in the current context.
889 elsif Has_Task (Desig_Type)
890 and then Comes_From_Source (Related_Nod)
891 and then not Restriction_Active (No_Task_Hierarchy)
893 if not Has_Master_Entity (Current_Scope) then
895 Make_Object_Declaration (Loc,
896 Defining_Identifier =>
897 Make_Defining_Identifier (Loc, Name_uMaster),
898 Constant_Present => True,
900 New_Reference_To (RTE (RE_Master_Id), Loc),
902 Make_Explicit_Dereference (Loc,
903 New_Reference_To (RTE (RE_Current_Master), Loc)));
905 Insert_Before (Related_Nod, Decl);
908 Set_Master_Id (Anon_Type, Defining_Identifier (Decl));
909 Set_Has_Master_Entity (Current_Scope);
911 Build_Master_Renaming (Related_Nod, Anon_Type);
916 -- For a private component of a protected type, it is imperative that
917 -- the back-end elaborate the type immediately after the protected
918 -- declaration, because this type will be used in the declarations
919 -- created for the component within each protected body, so we must
920 -- create an itype reference for it now.
922 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
923 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
925 -- Similarly, if the access definition is the return result of a
926 -- function, create an itype reference for it because it will be used
927 -- within the function body. For a regular function that is not a
928 -- compilation unit, insert reference after the declaration. For a
929 -- protected operation, insert it after the enclosing protected type
930 -- declaration. In either case, do not create a reference for a type
931 -- obtained through a limited_with clause, because this would introduce
932 -- semantic dependencies.
934 -- Similarly, do not create a reference if the designated type is a
935 -- generic formal, because no use of it will reach the backend.
937 elsif Nkind (Related_Nod) = N_Function_Specification
938 and then not From_With_Type (Desig_Type)
939 and then not Is_Generic_Type (Desig_Type)
941 if Present (Enclosing_Prot_Type) then
942 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
944 elsif Is_List_Member (Parent (Related_Nod))
945 and then Nkind (Parent (N)) /= N_Parameter_Specification
947 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
950 -- Finally, create an itype reference for an object declaration of an
951 -- anonymous access type. This is strictly necessary only for deferred
952 -- constants, but in any case will avoid out-of-scope problems in the
955 elsif Nkind (Related_Nod) = N_Object_Declaration then
956 Build_Itype_Reference (Anon_Type, Related_Nod);
960 end Access_Definition;
962 -----------------------------------
963 -- Access_Subprogram_Declaration --
964 -----------------------------------
966 procedure Access_Subprogram_Declaration
971 procedure Check_For_Premature_Usage (Def : Node_Id);
972 -- Check that type T_Name is not used, directly or recursively, as a
973 -- parameter or a return type in Def. Def is either a subtype, an
974 -- access_definition, or an access_to_subprogram_definition.
976 -------------------------------
977 -- Check_For_Premature_Usage --
978 -------------------------------
980 procedure Check_For_Premature_Usage (Def : Node_Id) is
984 -- Check for a subtype mark
986 if Nkind (Def) in N_Has_Etype then
987 if Etype (Def) = T_Name then
989 ("type& cannot be used before end of its declaration", Def);
992 -- If this is not a subtype, then this is an access_definition
994 elsif Nkind (Def) = N_Access_Definition then
995 if Present (Access_To_Subprogram_Definition (Def)) then
996 Check_For_Premature_Usage
997 (Access_To_Subprogram_Definition (Def));
999 Check_For_Premature_Usage (Subtype_Mark (Def));
1002 -- The only cases left are N_Access_Function_Definition and
1003 -- N_Access_Procedure_Definition.
1006 if Present (Parameter_Specifications (Def)) then
1007 Param := First (Parameter_Specifications (Def));
1008 while Present (Param) loop
1009 Check_For_Premature_Usage (Parameter_Type (Param));
1010 Param := Next (Param);
1014 if Nkind (Def) = N_Access_Function_Definition then
1015 Check_For_Premature_Usage (Result_Definition (Def));
1018 end Check_For_Premature_Usage;
1022 Formals : constant List_Id := Parameter_Specifications (T_Def);
1025 Desig_Type : constant Entity_Id :=
1026 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1028 -- Start of processing for Access_Subprogram_Declaration
1031 Check_SPARK_Restriction ("access type is not allowed", T_Def);
1033 -- Associate the Itype node with the inner full-type declaration or
1034 -- subprogram spec or entry body. This is required to handle nested
1035 -- anonymous declarations. For example:
1038 -- (X : access procedure
1039 -- (Y : access procedure
1042 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1043 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1044 N_Private_Type_Declaration,
1045 N_Private_Extension_Declaration,
1046 N_Procedure_Specification,
1047 N_Function_Specification,
1051 Nkind_In (D_Ityp, N_Object_Declaration,
1052 N_Object_Renaming_Declaration,
1053 N_Formal_Object_Declaration,
1054 N_Formal_Type_Declaration,
1055 N_Task_Type_Declaration,
1056 N_Protected_Type_Declaration))
1058 D_Ityp := Parent (D_Ityp);
1059 pragma Assert (D_Ityp /= Empty);
1062 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1064 if Nkind_In (D_Ityp, N_Procedure_Specification,
1065 N_Function_Specification)
1067 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1069 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1070 N_Object_Declaration,
1071 N_Object_Renaming_Declaration,
1072 N_Formal_Type_Declaration)
1074 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1077 if Nkind (T_Def) = N_Access_Function_Definition then
1078 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1080 Acc : constant Node_Id := Result_Definition (T_Def);
1083 if Present (Access_To_Subprogram_Definition (Acc))
1085 Protected_Present (Access_To_Subprogram_Definition (Acc))
1089 Replace_Anonymous_Access_To_Protected_Subprogram
1095 Access_Definition (T_Def, Result_Definition (T_Def)));
1100 Analyze (Result_Definition (T_Def));
1103 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1106 -- If a null exclusion is imposed on the result type, then
1107 -- create a null-excluding itype (an access subtype) and use
1108 -- it as the function's Etype.
1110 if Is_Access_Type (Typ)
1111 and then Null_Exclusion_In_Return_Present (T_Def)
1113 Set_Etype (Desig_Type,
1114 Create_Null_Excluding_Itype
1116 Related_Nod => T_Def,
1117 Scope_Id => Current_Scope));
1120 if From_With_Type (Typ) then
1122 -- AI05-151: Incomplete types are allowed in all basic
1123 -- declarations, including access to subprograms.
1125 if Ada_Version >= Ada_2012 then
1130 ("illegal use of incomplete type&",
1131 Result_Definition (T_Def), Typ);
1134 elsif Ekind (Current_Scope) = E_Package
1135 and then In_Private_Part (Current_Scope)
1137 if Ekind (Typ) = E_Incomplete_Type then
1138 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1140 elsif Is_Class_Wide_Type (Typ)
1141 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1144 (Desig_Type, Private_Dependents (Etype (Typ)));
1148 Set_Etype (Desig_Type, Typ);
1153 if not (Is_Type (Etype (Desig_Type))) then
1155 ("expect type in function specification",
1156 Result_Definition (T_Def));
1160 Set_Etype (Desig_Type, Standard_Void_Type);
1163 if Present (Formals) then
1164 Push_Scope (Desig_Type);
1166 -- A bit of a kludge here. These kludges will be removed when Itypes
1167 -- have proper parent pointers to their declarations???
1169 -- Kludge 1) Link defining_identifier of formals. Required by
1170 -- First_Formal to provide its functionality.
1176 F := First (Formals);
1178 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1179 -- when it is part of an unconstrained type and subtype expansion
1180 -- is disabled. To avoid back-end problems with shared profiles,
1181 -- use previous subprogram type as the designated type.
1184 and then Present (Scope (Defining_Identifier (F)))
1186 Set_Etype (T_Name, T_Name);
1187 Init_Size_Align (T_Name);
1188 Set_Directly_Designated_Type (T_Name,
1189 Scope (Defining_Identifier (F)));
1193 while Present (F) loop
1194 if No (Parent (Defining_Identifier (F))) then
1195 Set_Parent (Defining_Identifier (F), F);
1202 Process_Formals (Formals, Parent (T_Def));
1204 -- Kludge 2) End_Scope requires that the parent pointer be set to
1205 -- something reasonable, but Itypes don't have parent pointers. So
1206 -- we set it and then unset it ???
1208 Set_Parent (Desig_Type, T_Name);
1210 Set_Parent (Desig_Type, Empty);
1213 -- Check for premature usage of the type being defined
1215 Check_For_Premature_Usage (T_Def);
1217 -- The return type and/or any parameter type may be incomplete. Mark
1218 -- the subprogram_type as depending on the incomplete type, so that
1219 -- it can be updated when the full type declaration is seen. This
1220 -- only applies to incomplete types declared in some enclosing scope,
1221 -- not to limited views from other packages.
1223 if Present (Formals) then
1224 Formal := First_Formal (Desig_Type);
1225 while Present (Formal) loop
1226 if Ekind (Formal) /= E_In_Parameter
1227 and then Nkind (T_Def) = N_Access_Function_Definition
1229 Error_Msg_N ("functions can only have IN parameters", Formal);
1232 if Ekind (Etype (Formal)) = E_Incomplete_Type
1233 and then In_Open_Scopes (Scope (Etype (Formal)))
1235 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1236 Set_Has_Delayed_Freeze (Desig_Type);
1239 Next_Formal (Formal);
1243 -- If the return type is incomplete, this is legal as long as the
1244 -- type is declared in the current scope and will be completed in
1245 -- it (rather than being part of limited view).
1247 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1248 and then not Has_Delayed_Freeze (Desig_Type)
1249 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1251 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1252 Set_Has_Delayed_Freeze (Desig_Type);
1255 Check_Delayed_Subprogram (Desig_Type);
1257 if Protected_Present (T_Def) then
1258 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1259 Set_Convention (Desig_Type, Convention_Protected);
1261 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1264 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1266 Set_Etype (T_Name, T_Name);
1267 Init_Size_Align (T_Name);
1268 Set_Directly_Designated_Type (T_Name, Desig_Type);
1270 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1272 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1274 Check_Restriction (No_Access_Subprograms, T_Def);
1275 end Access_Subprogram_Declaration;
1277 ----------------------------
1278 -- Access_Type_Declaration --
1279 ----------------------------
1281 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1282 P : constant Node_Id := Parent (Def);
1283 S : constant Node_Id := Subtype_Indication (Def);
1285 Full_Desig : Entity_Id;
1288 Check_SPARK_Restriction ("access type is not allowed", Def);
1290 -- Check for permissible use of incomplete type
1292 if Nkind (S) /= N_Subtype_Indication then
1295 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1296 Set_Directly_Designated_Type (T, Entity (S));
1298 Set_Directly_Designated_Type (T,
1299 Process_Subtype (S, P, T, 'P'));
1303 Set_Directly_Designated_Type (T,
1304 Process_Subtype (S, P, T, 'P'));
1307 if All_Present (Def) or Constant_Present (Def) then
1308 Set_Ekind (T, E_General_Access_Type);
1310 Set_Ekind (T, E_Access_Type);
1313 Full_Desig := Designated_Type (T);
1315 if Base_Type (Full_Desig) = T then
1316 Error_Msg_N ("access type cannot designate itself", S);
1318 -- In Ada 2005, the type may have a limited view through some unit
1319 -- in its own context, allowing the following circularity that cannot
1320 -- be detected earlier
1322 elsif Is_Class_Wide_Type (Full_Desig)
1323 and then Etype (Full_Desig) = T
1326 ("access type cannot designate its own classwide type", S);
1328 -- Clean up indication of tagged status to prevent cascaded errors
1330 Set_Is_Tagged_Type (T, False);
1335 -- If the type has appeared already in a with_type clause, it is
1336 -- frozen and the pointer size is already set. Else, initialize.
1338 if not From_With_Type (T) then
1339 Init_Size_Align (T);
1342 -- Note that Has_Task is always false, since the access type itself
1343 -- is not a task type. See Einfo for more description on this point.
1344 -- Exactly the same consideration applies to Has_Controlled_Component.
1346 Set_Has_Task (T, False);
1347 Set_Has_Controlled_Component (T, False);
1349 -- Initialize Associated_Collection explicitly to Empty, to avoid
1350 -- problems where an incomplete view of this entity has been previously
1351 -- established by a limited with and an overlaid version of this field
1352 -- (Stored_Constraint) was initialized for the incomplete view.
1354 -- This reset is performed in most cases except where the access type
1355 -- has been created for the purposes of allocating or deallocating a
1356 -- build-in-place object. Such access types have explicitly set pools
1359 if No (Associated_Storage_Pool (T)) then
1360 Set_Associated_Collection (T, Empty);
1363 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1366 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1367 Set_Is_Access_Constant (T, Constant_Present (Def));
1368 end Access_Type_Declaration;
1370 ----------------------------------
1371 -- Add_Interface_Tag_Components --
1372 ----------------------------------
1374 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1375 Loc : constant Source_Ptr := Sloc (N);
1379 procedure Add_Tag (Iface : Entity_Id);
1380 -- Add tag for one of the progenitor interfaces
1386 procedure Add_Tag (Iface : Entity_Id) is
1393 pragma Assert (Is_Tagged_Type (Iface)
1394 and then Is_Interface (Iface));
1396 -- This is a reasonable place to propagate predicates
1398 if Has_Predicates (Iface) then
1399 Set_Has_Predicates (Typ);
1403 Make_Component_Definition (Loc,
1404 Aliased_Present => True,
1405 Subtype_Indication =>
1406 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1408 Tag := Make_Temporary (Loc, 'V');
1411 Make_Component_Declaration (Loc,
1412 Defining_Identifier => Tag,
1413 Component_Definition => Def);
1415 Analyze_Component_Declaration (Decl);
1417 Set_Analyzed (Decl);
1418 Set_Ekind (Tag, E_Component);
1420 Set_Is_Aliased (Tag);
1421 Set_Related_Type (Tag, Iface);
1422 Init_Component_Location (Tag);
1424 pragma Assert (Is_Frozen (Iface));
1426 Set_DT_Entry_Count (Tag,
1427 DT_Entry_Count (First_Entity (Iface)));
1429 if No (Last_Tag) then
1432 Insert_After (Last_Tag, Decl);
1437 -- If the ancestor has discriminants we need to give special support
1438 -- to store the offset_to_top value of the secondary dispatch tables.
1439 -- For this purpose we add a supplementary component just after the
1440 -- field that contains the tag associated with each secondary DT.
1442 if Typ /= Etype (Typ)
1443 and then Has_Discriminants (Etype (Typ))
1446 Make_Component_Definition (Loc,
1447 Subtype_Indication =>
1448 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1450 Offset := Make_Temporary (Loc, 'V');
1453 Make_Component_Declaration (Loc,
1454 Defining_Identifier => Offset,
1455 Component_Definition => Def);
1457 Analyze_Component_Declaration (Decl);
1459 Set_Analyzed (Decl);
1460 Set_Ekind (Offset, E_Component);
1461 Set_Is_Aliased (Offset);
1462 Set_Related_Type (Offset, Iface);
1463 Init_Component_Location (Offset);
1464 Insert_After (Last_Tag, Decl);
1475 -- Start of processing for Add_Interface_Tag_Components
1478 if not RTE_Available (RE_Interface_Tag) then
1480 ("(Ada 2005) interface types not supported by this run-time!",
1485 if Ekind (Typ) /= E_Record_Type
1486 or else (Is_Concurrent_Record_Type (Typ)
1487 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1488 or else (not Is_Concurrent_Record_Type (Typ)
1489 and then No (Interfaces (Typ))
1490 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1495 -- Find the current last tag
1497 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1498 Ext := Record_Extension_Part (Type_Definition (N));
1500 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1501 Ext := Type_Definition (N);
1506 if not (Present (Component_List (Ext))) then
1507 Set_Null_Present (Ext, False);
1509 Set_Component_List (Ext,
1510 Make_Component_List (Loc,
1511 Component_Items => L,
1512 Null_Present => False));
1514 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1515 L := Component_Items
1517 (Record_Extension_Part
1518 (Type_Definition (N))));
1520 L := Component_Items
1522 (Type_Definition (N)));
1525 -- Find the last tag component
1528 while Present (Comp) loop
1529 if Nkind (Comp) = N_Component_Declaration
1530 and then Is_Tag (Defining_Identifier (Comp))
1539 -- At this point L references the list of components and Last_Tag
1540 -- references the current last tag (if any). Now we add the tag
1541 -- corresponding with all the interfaces that are not implemented
1544 if Present (Interfaces (Typ)) then
1545 Elmt := First_Elmt (Interfaces (Typ));
1546 while Present (Elmt) loop
1547 Add_Tag (Node (Elmt));
1551 end Add_Interface_Tag_Components;
1553 -------------------------------------
1554 -- Add_Internal_Interface_Entities --
1555 -------------------------------------
1557 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1560 Iface_Elmt : Elmt_Id;
1561 Iface_Prim : Entity_Id;
1562 Ifaces_List : Elist_Id;
1563 New_Subp : Entity_Id := Empty;
1565 Restore_Scope : Boolean := False;
1568 pragma Assert (Ada_Version >= Ada_2005
1569 and then Is_Record_Type (Tagged_Type)
1570 and then Is_Tagged_Type (Tagged_Type)
1571 and then Has_Interfaces (Tagged_Type)
1572 and then not Is_Interface (Tagged_Type));
1574 -- Ensure that the internal entities are added to the scope of the type
1576 if Scope (Tagged_Type) /= Current_Scope then
1577 Push_Scope (Scope (Tagged_Type));
1578 Restore_Scope := True;
1581 Collect_Interfaces (Tagged_Type, Ifaces_List);
1583 Iface_Elmt := First_Elmt (Ifaces_List);
1584 while Present (Iface_Elmt) loop
1585 Iface := Node (Iface_Elmt);
1587 -- Originally we excluded here from this processing interfaces that
1588 -- are parents of Tagged_Type because their primitives are located
1589 -- in the primary dispatch table (and hence no auxiliary internal
1590 -- entities are required to handle secondary dispatch tables in such
1591 -- case). However, these auxiliary entities are also required to
1592 -- handle derivations of interfaces in formals of generics (see
1593 -- Derive_Subprograms).
1595 Elmt := First_Elmt (Primitive_Operations (Iface));
1596 while Present (Elmt) loop
1597 Iface_Prim := Node (Elmt);
1599 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1601 Find_Primitive_Covering_Interface
1602 (Tagged_Type => Tagged_Type,
1603 Iface_Prim => Iface_Prim);
1605 pragma Assert (Present (Prim));
1607 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1608 -- differs from the name of the interface primitive then it is
1609 -- a private primitive inherited from a parent type. In such
1610 -- case, given that Tagged_Type covers the interface, the
1611 -- inherited private primitive becomes visible. For such
1612 -- purpose we add a new entity that renames the inherited
1613 -- private primitive.
1615 if Chars (Prim) /= Chars (Iface_Prim) then
1616 pragma Assert (Has_Suffix (Prim, 'P'));
1618 (New_Subp => New_Subp,
1619 Parent_Subp => Iface_Prim,
1620 Derived_Type => Tagged_Type,
1621 Parent_Type => Iface);
1622 Set_Alias (New_Subp, Prim);
1623 Set_Is_Abstract_Subprogram
1624 (New_Subp, Is_Abstract_Subprogram (Prim));
1628 (New_Subp => New_Subp,
1629 Parent_Subp => Iface_Prim,
1630 Derived_Type => Tagged_Type,
1631 Parent_Type => Iface);
1633 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1634 -- associated with interface types. These entities are
1635 -- only registered in the list of primitives of its
1636 -- corresponding tagged type because they are only used
1637 -- to fill the contents of the secondary dispatch tables.
1638 -- Therefore they are removed from the homonym chains.
1640 Set_Is_Hidden (New_Subp);
1641 Set_Is_Internal (New_Subp);
1642 Set_Alias (New_Subp, Prim);
1643 Set_Is_Abstract_Subprogram
1644 (New_Subp, Is_Abstract_Subprogram (Prim));
1645 Set_Interface_Alias (New_Subp, Iface_Prim);
1647 -- Internal entities associated with interface types are
1648 -- only registered in the list of primitives of the tagged
1649 -- type. They are only used to fill the contents of the
1650 -- secondary dispatch tables. Therefore they are not needed
1651 -- in the homonym chains.
1653 Remove_Homonym (New_Subp);
1655 -- Hidden entities associated with interfaces must have set
1656 -- the Has_Delay_Freeze attribute to ensure that, in case of
1657 -- locally defined tagged types (or compiling with static
1658 -- dispatch tables generation disabled) the corresponding
1659 -- entry of the secondary dispatch table is filled when
1660 -- such an entity is frozen.
1662 Set_Has_Delayed_Freeze (New_Subp);
1668 Next_Elmt (Iface_Elmt);
1671 if Restore_Scope then
1674 end Add_Internal_Interface_Entities;
1676 -----------------------------------
1677 -- Analyze_Component_Declaration --
1678 -----------------------------------
1680 procedure Analyze_Component_Declaration (N : Node_Id) is
1681 Id : constant Entity_Id := Defining_Identifier (N);
1682 E : constant Node_Id := Expression (N);
1683 Typ : constant Node_Id :=
1684 Subtype_Indication (Component_Definition (N));
1688 function Contains_POC (Constr : Node_Id) return Boolean;
1689 -- Determines whether a constraint uses the discriminant of a record
1690 -- type thus becoming a per-object constraint (POC).
1692 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1693 -- Typ is the type of the current component, check whether this type is
1694 -- a limited type. Used to validate declaration against that of
1695 -- enclosing record.
1701 function Contains_POC (Constr : Node_Id) return Boolean is
1703 -- Prevent cascaded errors
1705 if Error_Posted (Constr) then
1709 case Nkind (Constr) is
1710 when N_Attribute_Reference =>
1712 Attribute_Name (Constr) = Name_Access
1713 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1715 when N_Discriminant_Association =>
1716 return Denotes_Discriminant (Expression (Constr));
1718 when N_Identifier =>
1719 return Denotes_Discriminant (Constr);
1721 when N_Index_Or_Discriminant_Constraint =>
1726 IDC := First (Constraints (Constr));
1727 while Present (IDC) loop
1729 -- One per-object constraint is sufficient
1731 if Contains_POC (IDC) then
1742 return Denotes_Discriminant (Low_Bound (Constr))
1744 Denotes_Discriminant (High_Bound (Constr));
1746 when N_Range_Constraint =>
1747 return Denotes_Discriminant (Range_Expression (Constr));
1755 ----------------------
1756 -- Is_Known_Limited --
1757 ----------------------
1759 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1760 P : constant Entity_Id := Etype (Typ);
1761 R : constant Entity_Id := Root_Type (Typ);
1764 if Is_Limited_Record (Typ) then
1767 -- If the root type is limited (and not a limited interface)
1768 -- so is the current type
1770 elsif Is_Limited_Record (R)
1772 (not Is_Interface (R)
1773 or else not Is_Limited_Interface (R))
1777 -- Else the type may have a limited interface progenitor, but a
1778 -- limited record parent.
1781 and then Is_Limited_Record (P)
1788 end Is_Known_Limited;
1790 -- Start of processing for Analyze_Component_Declaration
1793 Generate_Definition (Id);
1796 if Present (Typ) then
1797 T := Find_Type_Of_Object
1798 (Subtype_Indication (Component_Definition (N)), N);
1800 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1801 Check_SPARK_Restriction ("subtype mark required", Typ);
1804 -- Ada 2005 (AI-230): Access Definition case
1807 pragma Assert (Present
1808 (Access_Definition (Component_Definition (N))));
1810 T := Access_Definition
1812 N => Access_Definition (Component_Definition (N)));
1813 Set_Is_Local_Anonymous_Access (T);
1815 -- Ada 2005 (AI-254)
1817 if Present (Access_To_Subprogram_Definition
1818 (Access_Definition (Component_Definition (N))))
1819 and then Protected_Present (Access_To_Subprogram_Definition
1821 (Component_Definition (N))))
1823 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1827 -- If the subtype is a constrained subtype of the enclosing record,
1828 -- (which must have a partial view) the back-end does not properly
1829 -- handle the recursion. Rewrite the component declaration with an
1830 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1831 -- the tree directly because side effects have already been removed from
1832 -- discriminant constraints.
1834 if Ekind (T) = E_Access_Subtype
1835 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1836 and then Comes_From_Source (T)
1837 and then Nkind (Parent (T)) = N_Subtype_Declaration
1838 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1841 (Subtype_Indication (Component_Definition (N)),
1842 New_Copy_Tree (Subtype_Indication (Parent (T))));
1843 T := Find_Type_Of_Object
1844 (Subtype_Indication (Component_Definition (N)), N);
1847 -- If the component declaration includes a default expression, then we
1848 -- check that the component is not of a limited type (RM 3.7(5)),
1849 -- and do the special preanalysis of the expression (see section on
1850 -- "Handling of Default and Per-Object Expressions" in the spec of
1854 Check_SPARK_Restriction ("default expression is not allowed", E);
1855 Preanalyze_Spec_Expression (E, T);
1856 Check_Initialization (T, E);
1858 if Ada_Version >= Ada_2005
1859 and then Ekind (T) = E_Anonymous_Access_Type
1860 and then Etype (E) /= Any_Type
1862 -- Check RM 3.9.2(9): "if the expected type for an expression is
1863 -- an anonymous access-to-specific tagged type, then the object
1864 -- designated by the expression shall not be dynamically tagged
1865 -- unless it is a controlling operand in a call on a dispatching
1868 if Is_Tagged_Type (Directly_Designated_Type (T))
1870 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1872 Ekind (Directly_Designated_Type (Etype (E))) =
1876 ("access to specific tagged type required (RM 3.9.2(9))", E);
1879 -- (Ada 2005: AI-230): Accessibility check for anonymous
1882 if Type_Access_Level (Etype (E)) > Type_Access_Level (T) then
1884 ("expression has deeper access level than component " &
1885 "(RM 3.10.2 (12.2))", E);
1888 -- The initialization expression is a reference to an access
1889 -- discriminant. The type of the discriminant is always deeper
1890 -- than any access type.
1892 if Ekind (Etype (E)) = E_Anonymous_Access_Type
1893 and then Is_Entity_Name (E)
1894 and then Ekind (Entity (E)) = E_In_Parameter
1895 and then Present (Discriminal_Link (Entity (E)))
1898 ("discriminant has deeper accessibility level than target",
1904 -- The parent type may be a private view with unknown discriminants,
1905 -- and thus unconstrained. Regular components must be constrained.
1907 if Is_Indefinite_Subtype (T) and then Chars (Id) /= Name_uParent then
1908 if Is_Class_Wide_Type (T) then
1910 ("class-wide subtype with unknown discriminants" &
1911 " in component declaration",
1912 Subtype_Indication (Component_Definition (N)));
1915 ("unconstrained subtype in component declaration",
1916 Subtype_Indication (Component_Definition (N)));
1919 -- Components cannot be abstract, except for the special case of
1920 -- the _Parent field (case of extending an abstract tagged type)
1922 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
1923 Error_Msg_N ("type of a component cannot be abstract", N);
1927 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
1929 -- The component declaration may have a per-object constraint, set
1930 -- the appropriate flag in the defining identifier of the subtype.
1932 if Present (Subtype_Indication (Component_Definition (N))) then
1934 Sindic : constant Node_Id :=
1935 Subtype_Indication (Component_Definition (N));
1937 if Nkind (Sindic) = N_Subtype_Indication
1938 and then Present (Constraint (Sindic))
1939 and then Contains_POC (Constraint (Sindic))
1941 Set_Has_Per_Object_Constraint (Id);
1946 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
1947 -- out some static checks.
1949 if Ada_Version >= Ada_2005
1950 and then Can_Never_Be_Null (T)
1952 Null_Exclusion_Static_Checks (N);
1955 -- If this component is private (or depends on a private type), flag the
1956 -- record type to indicate that some operations are not available.
1958 P := Private_Component (T);
1962 -- Check for circular definitions
1964 if P = Any_Type then
1965 Set_Etype (Id, Any_Type);
1967 -- There is a gap in the visibility of operations only if the
1968 -- component type is not defined in the scope of the record type.
1970 elsif Scope (P) = Scope (Current_Scope) then
1973 elsif Is_Limited_Type (P) then
1974 Set_Is_Limited_Composite (Current_Scope);
1977 Set_Is_Private_Composite (Current_Scope);
1982 and then Is_Limited_Type (T)
1983 and then Chars (Id) /= Name_uParent
1984 and then Is_Tagged_Type (Current_Scope)
1986 if Is_Derived_Type (Current_Scope)
1987 and then not Is_Known_Limited (Current_Scope)
1990 ("extension of nonlimited type cannot have limited components",
1993 if Is_Interface (Root_Type (Current_Scope)) then
1995 ("\limitedness is not inherited from limited interface", N);
1996 Error_Msg_N ("\add LIMITED to type indication", N);
1999 Explain_Limited_Type (T, N);
2000 Set_Etype (Id, Any_Type);
2001 Set_Is_Limited_Composite (Current_Scope, False);
2003 elsif not Is_Derived_Type (Current_Scope)
2004 and then not Is_Limited_Record (Current_Scope)
2005 and then not Is_Concurrent_Type (Current_Scope)
2008 ("nonlimited tagged type cannot have limited components", N);
2009 Explain_Limited_Type (T, N);
2010 Set_Etype (Id, Any_Type);
2011 Set_Is_Limited_Composite (Current_Scope, False);
2015 Set_Original_Record_Component (Id, Id);
2017 if Has_Aspects (N) then
2018 Analyze_Aspect_Specifications (N, Id);
2020 end Analyze_Component_Declaration;
2022 --------------------------
2023 -- Analyze_Declarations --
2024 --------------------------
2026 procedure Analyze_Declarations (L : List_Id) is
2028 Freeze_From : Entity_Id := Empty;
2029 Next_Node : Node_Id;
2032 -- Adjust D not to include implicit label declarations, since these
2033 -- have strange Sloc values that result in elaboration check problems.
2034 -- (They have the sloc of the label as found in the source, and that
2035 -- is ahead of the current declarative part).
2041 procedure Adjust_D is
2043 while Present (Prev (D))
2044 and then Nkind (D) = N_Implicit_Label_Declaration
2050 -- Start of processing for Analyze_Declarations
2053 if SPARK_Mode or else Restriction_Check_Required (SPARK) then
2054 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2058 while Present (D) loop
2060 -- Package specification cannot contain a package declaration in
2063 if Nkind (D) = N_Package_Declaration
2064 and then Nkind (Parent (L)) = N_Package_Specification
2066 Check_SPARK_Restriction ("package specification cannot contain "
2067 & "a package declaration", D);
2070 -- Complete analysis of declaration
2073 Next_Node := Next (D);
2075 if No (Freeze_From) then
2076 Freeze_From := First_Entity (Current_Scope);
2079 -- At the end of a declarative part, freeze remaining entities
2080 -- declared in it. The end of the visible declarations of package
2081 -- specification is not the end of a declarative part if private
2082 -- declarations are present. The end of a package declaration is a
2083 -- freezing point only if it a library package. A task definition or
2084 -- protected type definition is not a freeze point either. Finally,
2085 -- we do not freeze entities in generic scopes, because there is no
2086 -- code generated for them and freeze nodes will be generated for
2089 -- The end of a package instantiation is not a freeze point, but
2090 -- for now we make it one, because the generic body is inserted
2091 -- (currently) immediately after. Generic instantiations will not
2092 -- be a freeze point once delayed freezing of bodies is implemented.
2093 -- (This is needed in any case for early instantiations ???).
2095 if No (Next_Node) then
2096 if Nkind_In (Parent (L), N_Component_List,
2098 N_Protected_Definition)
2102 elsif Nkind (Parent (L)) /= N_Package_Specification then
2103 if Nkind (Parent (L)) = N_Package_Body then
2104 Freeze_From := First_Entity (Current_Scope);
2108 Freeze_All (Freeze_From, D);
2109 Freeze_From := Last_Entity (Current_Scope);
2111 elsif Scope (Current_Scope) /= Standard_Standard
2112 and then not Is_Child_Unit (Current_Scope)
2113 and then No (Generic_Parent (Parent (L)))
2117 elsif L /= Visible_Declarations (Parent (L))
2118 or else No (Private_Declarations (Parent (L)))
2119 or else Is_Empty_List (Private_Declarations (Parent (L)))
2122 Freeze_All (Freeze_From, D);
2123 Freeze_From := Last_Entity (Current_Scope);
2126 -- If next node is a body then freeze all types before the body.
2127 -- An exception occurs for some expander-generated bodies. If these
2128 -- are generated at places where in general language rules would not
2129 -- allow a freeze point, then we assume that the expander has
2130 -- explicitly checked that all required types are properly frozen,
2131 -- and we do not cause general freezing here. This special circuit
2132 -- is used when the encountered body is marked as having already
2135 -- In all other cases (bodies that come from source, and expander
2136 -- generated bodies that have not been analyzed yet), freeze all
2137 -- types now. Note that in the latter case, the expander must take
2138 -- care to attach the bodies at a proper place in the tree so as to
2139 -- not cause unwanted freezing at that point.
2141 elsif not Analyzed (Next_Node)
2142 and then (Nkind_In (Next_Node, N_Subprogram_Body,
2148 Nkind (Next_Node) in N_Body_Stub)
2151 Freeze_All (Freeze_From, D);
2152 Freeze_From := Last_Entity (Current_Scope);
2158 -- One more thing to do, we need to scan the declarations to check
2159 -- for any precondition/postcondition pragmas (Pre/Post aspects have
2160 -- by this stage been converted into corresponding pragmas). It is
2161 -- at this point that we analyze the expressions in such pragmas,
2162 -- to implement the delayed visibility requirement.
2172 while Present (Decl) loop
2173 if Nkind (Original_Node (Decl)) = N_Subprogram_Declaration then
2174 Spec := Specification (Original_Node (Decl));
2175 Sent := Defining_Unit_Name (Spec);
2176 Prag := Spec_PPC_List (Sent);
2177 while Present (Prag) loop
2178 Analyze_PPC_In_Decl_Part (Prag, Sent);
2179 Prag := Next_Pragma (Prag);
2186 end Analyze_Declarations;
2188 -----------------------------------
2189 -- Analyze_Full_Type_Declaration --
2190 -----------------------------------
2192 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2193 Def : constant Node_Id := Type_Definition (N);
2194 Def_Id : constant Entity_Id := Defining_Identifier (N);
2198 Is_Remote : constant Boolean :=
2199 (Is_Remote_Types (Current_Scope)
2200 or else Is_Remote_Call_Interface (Current_Scope))
2201 and then not (In_Private_Part (Current_Scope)
2202 or else In_Package_Body (Current_Scope));
2204 procedure Check_Ops_From_Incomplete_Type;
2205 -- If there is a tagged incomplete partial view of the type, traverse
2206 -- the primitives of the incomplete view and change the type of any
2207 -- controlling formals and result to indicate the full view. The
2208 -- primitives will be added to the full type's primitive operations
2209 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2210 -- is called from Process_Incomplete_Dependents).
2212 ------------------------------------
2213 -- Check_Ops_From_Incomplete_Type --
2214 ------------------------------------
2216 procedure Check_Ops_From_Incomplete_Type is
2223 and then Ekind (Prev) = E_Incomplete_Type
2224 and then Is_Tagged_Type (Prev)
2225 and then Is_Tagged_Type (T)
2227 Elmt := First_Elmt (Primitive_Operations (Prev));
2228 while Present (Elmt) loop
2231 Formal := First_Formal (Op);
2232 while Present (Formal) loop
2233 if Etype (Formal) = Prev then
2234 Set_Etype (Formal, T);
2237 Next_Formal (Formal);
2240 if Etype (Op) = Prev then
2247 end Check_Ops_From_Incomplete_Type;
2249 -- Start of processing for Analyze_Full_Type_Declaration
2252 Prev := Find_Type_Name (N);
2254 -- The full view, if present, now points to the current type
2256 -- Ada 2005 (AI-50217): If the type was previously decorated when
2257 -- imported through a LIMITED WITH clause, it appears as incomplete
2258 -- but has no full view.
2260 if Ekind (Prev) = E_Incomplete_Type
2261 and then Present (Full_View (Prev))
2263 T := Full_View (Prev);
2268 Set_Is_Pure (T, Is_Pure (Current_Scope));
2270 -- We set the flag Is_First_Subtype here. It is needed to set the
2271 -- corresponding flag for the Implicit class-wide-type created
2272 -- during tagged types processing.
2274 Set_Is_First_Subtype (T, True);
2276 -- Only composite types other than array types are allowed to have
2281 -- For derived types, the rule will be checked once we've figured
2282 -- out the parent type.
2284 when N_Derived_Type_Definition =>
2287 -- For record types, discriminants are allowed, unless we are in
2290 when N_Record_Definition =>
2291 if Present (Discriminant_Specifications (N)) then
2292 Check_SPARK_Restriction
2293 ("discriminant type is not allowed",
2295 (First (Discriminant_Specifications (N))));
2299 if Present (Discriminant_Specifications (N)) then
2301 ("elementary or array type cannot have discriminants",
2303 (First (Discriminant_Specifications (N))));
2307 -- Elaborate the type definition according to kind, and generate
2308 -- subsidiary (implicit) subtypes where needed. We skip this if it was
2309 -- already done (this happens during the reanalysis that follows a call
2310 -- to the high level optimizer).
2312 if not Analyzed (T) then
2317 when N_Access_To_Subprogram_Definition =>
2318 Access_Subprogram_Declaration (T, Def);
2320 -- If this is a remote access to subprogram, we must create the
2321 -- equivalent fat pointer type, and related subprograms.
2324 Process_Remote_AST_Declaration (N);
2327 -- Validate categorization rule against access type declaration
2328 -- usually a violation in Pure unit, Shared_Passive unit.
2330 Validate_Access_Type_Declaration (T, N);
2332 when N_Access_To_Object_Definition =>
2333 Access_Type_Declaration (T, Def);
2335 -- Validate categorization rule against access type declaration
2336 -- usually a violation in Pure unit, Shared_Passive unit.
2338 Validate_Access_Type_Declaration (T, N);
2340 -- If we are in a Remote_Call_Interface package and define a
2341 -- RACW, then calling stubs and specific stream attributes
2345 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
2347 Add_RACW_Features (Def_Id);
2350 -- Set no strict aliasing flag if config pragma seen
2352 if Opt.No_Strict_Aliasing then
2353 Set_No_Strict_Aliasing (Base_Type (Def_Id));
2356 when N_Array_Type_Definition =>
2357 Array_Type_Declaration (T, Def);
2359 when N_Derived_Type_Definition =>
2360 Derived_Type_Declaration (T, N, T /= Def_Id);
2362 when N_Enumeration_Type_Definition =>
2363 Enumeration_Type_Declaration (T, Def);
2365 when N_Floating_Point_Definition =>
2366 Floating_Point_Type_Declaration (T, Def);
2368 when N_Decimal_Fixed_Point_Definition =>
2369 Decimal_Fixed_Point_Type_Declaration (T, Def);
2371 when N_Ordinary_Fixed_Point_Definition =>
2372 Ordinary_Fixed_Point_Type_Declaration (T, Def);
2374 when N_Signed_Integer_Type_Definition =>
2375 Signed_Integer_Type_Declaration (T, Def);
2377 when N_Modular_Type_Definition =>
2378 Modular_Type_Declaration (T, Def);
2380 when N_Record_Definition =>
2381 Record_Type_Declaration (T, N, Prev);
2383 -- If declaration has a parse error, nothing to elaborate.
2389 raise Program_Error;
2394 if Etype (T) = Any_Type then
2398 -- Controlled type is not allowed in SPARK
2400 if Is_Visibly_Controlled (T) then
2401 Check_SPARK_Restriction ("controlled type is not allowed", N);
2404 -- Some common processing for all types
2406 Set_Depends_On_Private (T, Has_Private_Component (T));
2407 Check_Ops_From_Incomplete_Type;
2409 -- Both the declared entity, and its anonymous base type if one
2410 -- was created, need freeze nodes allocated.
2413 B : constant Entity_Id := Base_Type (T);
2416 -- In the case where the base type differs from the first subtype, we
2417 -- pre-allocate a freeze node, and set the proper link to the first
2418 -- subtype. Freeze_Entity will use this preallocated freeze node when
2419 -- it freezes the entity.
2421 -- This does not apply if the base type is a generic type, whose
2422 -- declaration is independent of the current derived definition.
2424 if B /= T and then not Is_Generic_Type (B) then
2425 Ensure_Freeze_Node (B);
2426 Set_First_Subtype_Link (Freeze_Node (B), T);
2429 -- A type that is imported through a limited_with clause cannot
2430 -- generate any code, and thus need not be frozen. However, an access
2431 -- type with an imported designated type needs a finalization list,
2432 -- which may be referenced in some other package that has non-limited
2433 -- visibility on the designated type. Thus we must create the
2434 -- finalization list at the point the access type is frozen, to
2435 -- prevent unsatisfied references at link time.
2437 if not From_With_Type (T) or else Is_Access_Type (T) then
2438 Set_Has_Delayed_Freeze (T);
2442 -- Case where T is the full declaration of some private type which has
2443 -- been swapped in Defining_Identifier (N).
2445 if T /= Def_Id and then Is_Private_Type (Def_Id) then
2446 Process_Full_View (N, T, Def_Id);
2448 -- Record the reference. The form of this is a little strange, since
2449 -- the full declaration has been swapped in. So the first parameter
2450 -- here represents the entity to which a reference is made which is
2451 -- the "real" entity, i.e. the one swapped in, and the second
2452 -- parameter provides the reference location.
2454 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
2455 -- since we don't want a complaint about the full type being an
2456 -- unwanted reference to the private type
2459 B : constant Boolean := Has_Pragma_Unreferenced (T);
2461 Set_Has_Pragma_Unreferenced (T, False);
2462 Generate_Reference (T, T, 'c');
2463 Set_Has_Pragma_Unreferenced (T, B);
2466 Set_Completion_Referenced (Def_Id);
2468 -- For completion of incomplete type, process incomplete dependents
2469 -- and always mark the full type as referenced (it is the incomplete
2470 -- type that we get for any real reference).
2472 elsif Ekind (Prev) = E_Incomplete_Type then
2473 Process_Incomplete_Dependents (N, T, Prev);
2474 Generate_Reference (Prev, Def_Id, 'c');
2475 Set_Completion_Referenced (Def_Id);
2477 -- If not private type or incomplete type completion, this is a real
2478 -- definition of a new entity, so record it.
2481 Generate_Definition (Def_Id);
2484 if Chars (Scope (Def_Id)) = Name_System
2485 and then Chars (Def_Id) = Name_Address
2486 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
2488 Set_Is_Descendent_Of_Address (Def_Id);
2489 Set_Is_Descendent_Of_Address (Base_Type (Def_Id));
2490 Set_Is_Descendent_Of_Address (Prev);
2493 Set_Optimize_Alignment_Flags (Def_Id);
2494 Check_Eliminated (Def_Id);
2496 if Has_Aspects (N) then
2497 Analyze_Aspect_Specifications (N, Def_Id);
2499 end Analyze_Full_Type_Declaration;
2501 ----------------------------------
2502 -- Analyze_Incomplete_Type_Decl --
2503 ----------------------------------
2505 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
2506 F : constant Boolean := Is_Pure (Current_Scope);
2510 Check_SPARK_Restriction ("incomplete type is not allowed", N);
2512 Generate_Definition (Defining_Identifier (N));
2514 -- Process an incomplete declaration. The identifier must not have been
2515 -- declared already in the scope. However, an incomplete declaration may
2516 -- appear in the private part of a package, for a private type that has
2517 -- already been declared.
2519 -- In this case, the discriminants (if any) must match
2521 T := Find_Type_Name (N);
2523 Set_Ekind (T, E_Incomplete_Type);
2524 Init_Size_Align (T);
2525 Set_Is_First_Subtype (T, True);
2528 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
2529 -- incomplete types.
2531 if Tagged_Present (N) then
2532 Set_Is_Tagged_Type (T);
2533 Make_Class_Wide_Type (T);
2534 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2539 Set_Stored_Constraint (T, No_Elist);
2541 if Present (Discriminant_Specifications (N)) then
2542 Process_Discriminants (N);
2547 -- If the type has discriminants, non-trivial subtypes may be
2548 -- declared before the full view of the type. The full views of those
2549 -- subtypes will be built after the full view of the type.
2551 Set_Private_Dependents (T, New_Elmt_List);
2553 end Analyze_Incomplete_Type_Decl;
2555 -----------------------------------
2556 -- Analyze_Interface_Declaration --
2557 -----------------------------------
2559 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
2560 CW : constant Entity_Id := Class_Wide_Type (T);
2563 Set_Is_Tagged_Type (T);
2565 Set_Is_Limited_Record (T, Limited_Present (Def)
2566 or else Task_Present (Def)
2567 or else Protected_Present (Def)
2568 or else Synchronized_Present (Def));
2570 -- Type is abstract if full declaration carries keyword, or if previous
2571 -- partial view did.
2573 Set_Is_Abstract_Type (T);
2574 Set_Is_Interface (T);
2576 -- Type is a limited interface if it includes the keyword limited, task,
2577 -- protected, or synchronized.
2579 Set_Is_Limited_Interface
2580 (T, Limited_Present (Def)
2581 or else Protected_Present (Def)
2582 or else Synchronized_Present (Def)
2583 or else Task_Present (Def));
2585 Set_Interfaces (T, New_Elmt_List);
2586 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2588 -- Complete the decoration of the class-wide entity if it was already
2589 -- built (i.e. during the creation of the limited view)
2591 if Present (CW) then
2592 Set_Is_Interface (CW);
2593 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
2596 -- Check runtime support for synchronized interfaces
2598 if VM_Target = No_VM
2599 and then (Is_Task_Interface (T)
2600 or else Is_Protected_Interface (T)
2601 or else Is_Synchronized_Interface (T))
2602 and then not RTE_Available (RE_Select_Specific_Data)
2604 Error_Msg_CRT ("synchronized interfaces", T);
2606 end Analyze_Interface_Declaration;
2608 -----------------------------
2609 -- Analyze_Itype_Reference --
2610 -----------------------------
2612 -- Nothing to do. This node is placed in the tree only for the benefit of
2613 -- back end processing, and has no effect on the semantic processing.
2615 procedure Analyze_Itype_Reference (N : Node_Id) is
2617 pragma Assert (Is_Itype (Itype (N)));
2619 end Analyze_Itype_Reference;
2621 --------------------------------
2622 -- Analyze_Number_Declaration --
2623 --------------------------------
2625 procedure Analyze_Number_Declaration (N : Node_Id) is
2626 Id : constant Entity_Id := Defining_Identifier (N);
2627 E : constant Node_Id := Expression (N);
2629 Index : Interp_Index;
2633 Generate_Definition (Id);
2636 -- This is an optimization of a common case of an integer literal
2638 if Nkind (E) = N_Integer_Literal then
2639 Set_Is_Static_Expression (E, True);
2640 Set_Etype (E, Universal_Integer);
2642 Set_Etype (Id, Universal_Integer);
2643 Set_Ekind (Id, E_Named_Integer);
2644 Set_Is_Frozen (Id, True);
2648 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2650 -- Process expression, replacing error by integer zero, to avoid
2651 -- cascaded errors or aborts further along in the processing
2653 -- Replace Error by integer zero, which seems least likely to
2654 -- cause cascaded errors.
2657 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
2658 Set_Error_Posted (E);
2663 -- Verify that the expression is static and numeric. If
2664 -- the expression is overloaded, we apply the preference
2665 -- rule that favors root numeric types.
2667 if not Is_Overloaded (E) then
2673 Get_First_Interp (E, Index, It);
2674 while Present (It.Typ) loop
2675 if (Is_Integer_Type (It.Typ)
2676 or else Is_Real_Type (It.Typ))
2677 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
2679 if T = Any_Type then
2682 elsif It.Typ = Universal_Real
2683 or else It.Typ = Universal_Integer
2685 -- Choose universal interpretation over any other
2692 Get_Next_Interp (Index, It);
2696 if Is_Integer_Type (T) then
2698 Set_Etype (Id, Universal_Integer);
2699 Set_Ekind (Id, E_Named_Integer);
2701 elsif Is_Real_Type (T) then
2703 -- Because the real value is converted to universal_real, this is a
2704 -- legal context for a universal fixed expression.
2706 if T = Universal_Fixed then
2708 Loc : constant Source_Ptr := Sloc (N);
2709 Conv : constant Node_Id := Make_Type_Conversion (Loc,
2711 New_Occurrence_Of (Universal_Real, Loc),
2712 Expression => Relocate_Node (E));
2719 elsif T = Any_Fixed then
2720 Error_Msg_N ("illegal context for mixed mode operation", E);
2722 -- Expression is of the form : universal_fixed * integer. Try to
2723 -- resolve as universal_real.
2725 T := Universal_Real;
2730 Set_Etype (Id, Universal_Real);
2731 Set_Ekind (Id, E_Named_Real);
2734 Wrong_Type (E, Any_Numeric);
2738 Set_Ekind (Id, E_Constant);
2739 Set_Never_Set_In_Source (Id, True);
2740 Set_Is_True_Constant (Id, True);
2744 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
2745 Set_Etype (E, Etype (Id));
2748 if not Is_OK_Static_Expression (E) then
2749 Flag_Non_Static_Expr
2750 ("non-static expression used in number declaration!", E);
2751 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
2752 Set_Etype (E, Any_Type);
2754 end Analyze_Number_Declaration;
2756 --------------------------------
2757 -- Analyze_Object_Declaration --
2758 --------------------------------
2760 procedure Analyze_Object_Declaration (N : Node_Id) is
2761 Loc : constant Source_Ptr := Sloc (N);
2762 Id : constant Entity_Id := Defining_Identifier (N);
2766 E : Node_Id := Expression (N);
2767 -- E is set to Expression (N) throughout this routine. When
2768 -- Expression (N) is modified, E is changed accordingly.
2770 Prev_Entity : Entity_Id := Empty;
2772 function Count_Tasks (T : Entity_Id) return Uint;
2773 -- This function is called when a non-generic library level object of a
2774 -- task type is declared. Its function is to count the static number of
2775 -- tasks declared within the type (it is only called if Has_Tasks is set
2776 -- for T). As a side effect, if an array of tasks with non-static bounds
2777 -- or a variant record type is encountered, Check_Restrictions is called
2778 -- indicating the count is unknown.
2784 function Count_Tasks (T : Entity_Id) return Uint is
2790 if Is_Task_Type (T) then
2793 elsif Is_Record_Type (T) then
2794 if Has_Discriminants (T) then
2795 Check_Restriction (Max_Tasks, N);
2800 C := First_Component (T);
2801 while Present (C) loop
2802 V := V + Count_Tasks (Etype (C));
2809 elsif Is_Array_Type (T) then
2810 X := First_Index (T);
2811 V := Count_Tasks (Component_Type (T));
2812 while Present (X) loop
2815 if not Is_Static_Subtype (C) then
2816 Check_Restriction (Max_Tasks, N);
2819 V := V * (UI_Max (Uint_0,
2820 Expr_Value (Type_High_Bound (C)) -
2821 Expr_Value (Type_Low_Bound (C)) + Uint_1));
2834 -- Start of processing for Analyze_Object_Declaration
2837 -- There are three kinds of implicit types generated by an
2838 -- object declaration:
2840 -- 1. Those generated by the original Object Definition
2842 -- 2. Those generated by the Expression
2844 -- 3. Those used to constrained the Object Definition with the
2845 -- expression constraints when it is unconstrained
2847 -- They must be generated in this order to avoid order of elaboration
2848 -- issues. Thus the first step (after entering the name) is to analyze
2849 -- the object definition.
2851 if Constant_Present (N) then
2852 Prev_Entity := Current_Entity_In_Scope (Id);
2854 if Present (Prev_Entity)
2856 -- If the homograph is an implicit subprogram, it is overridden
2857 -- by the current declaration.
2859 ((Is_Overloadable (Prev_Entity)
2860 and then Is_Inherited_Operation (Prev_Entity))
2862 -- The current object is a discriminal generated for an entry
2863 -- family index. Even though the index is a constant, in this
2864 -- particular context there is no true constant redeclaration.
2865 -- Enter_Name will handle the visibility.
2868 (Is_Discriminal (Id)
2869 and then Ekind (Discriminal_Link (Id)) =
2870 E_Entry_Index_Parameter)
2872 -- The current object is the renaming for a generic declared
2873 -- within the instance.
2876 (Ekind (Prev_Entity) = E_Package
2877 and then Nkind (Parent (Prev_Entity)) =
2878 N_Package_Renaming_Declaration
2879 and then not Comes_From_Source (Prev_Entity)
2880 and then Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
2882 Prev_Entity := Empty;
2886 if Present (Prev_Entity) then
2887 Constant_Redeclaration (Id, N, T);
2889 Generate_Reference (Prev_Entity, Id, 'c');
2890 Set_Completion_Referenced (Id);
2892 if Error_Posted (N) then
2894 -- Type mismatch or illegal redeclaration, Do not analyze
2895 -- expression to avoid cascaded errors.
2897 T := Find_Type_Of_Object (Object_Definition (N), N);
2899 Set_Ekind (Id, E_Variable);
2903 -- In the normal case, enter identifier at the start to catch premature
2904 -- usage in the initialization expression.
2907 Generate_Definition (Id);
2910 Mark_Coextensions (N, Object_Definition (N));
2912 T := Find_Type_Of_Object (Object_Definition (N), N);
2914 if Nkind (Object_Definition (N)) = N_Access_Definition
2916 (Access_To_Subprogram_Definition (Object_Definition (N)))
2917 and then Protected_Present
2918 (Access_To_Subprogram_Definition (Object_Definition (N)))
2920 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2923 if Error_Posted (Id) then
2925 Set_Ekind (Id, E_Variable);
2930 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2931 -- out some static checks
2933 if Ada_Version >= Ada_2005
2934 and then Can_Never_Be_Null (T)
2936 -- In case of aggregates we must also take care of the correct
2937 -- initialization of nested aggregates bug this is done at the
2938 -- point of the analysis of the aggregate (see sem_aggr.adb)
2940 if Present (Expression (N))
2941 and then Nkind (Expression (N)) = N_Aggregate
2947 Save_Typ : constant Entity_Id := Etype (Id);
2949 Set_Etype (Id, T); -- Temp. decoration for static checks
2950 Null_Exclusion_Static_Checks (N);
2951 Set_Etype (Id, Save_Typ);
2956 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2958 -- If deferred constant, make sure context is appropriate. We detect
2959 -- a deferred constant as a constant declaration with no expression.
2960 -- A deferred constant can appear in a package body if its completion
2961 -- is by means of an interface pragma.
2963 if Constant_Present (N)
2966 -- A deferred constant may appear in the declarative part of the
2967 -- following constructs:
2971 -- extended return statements
2974 -- subprogram bodies
2977 -- When declared inside a package spec, a deferred constant must be
2978 -- completed by a full constant declaration or pragma Import. In all
2979 -- other cases, the only proper completion is pragma Import. Extended
2980 -- return statements are flagged as invalid contexts because they do
2981 -- not have a declarative part and so cannot accommodate the pragma.
2983 if Ekind (Current_Scope) = E_Return_Statement then
2985 ("invalid context for deferred constant declaration (RM 7.4)",
2988 ("\declaration requires an initialization expression",
2990 Set_Constant_Present (N, False);
2992 -- In Ada 83, deferred constant must be of private type
2994 elsif not Is_Private_Type (T) then
2995 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
2997 ("(Ada 83) deferred constant must be private type", N);
3001 -- If not a deferred constant, then object declaration freezes its type
3004 Check_Fully_Declared (T, N);
3005 Freeze_Before (N, T);
3008 -- If the object was created by a constrained array definition, then
3009 -- set the link in both the anonymous base type and anonymous subtype
3010 -- that are built to represent the array type to point to the object.
3012 if Nkind (Object_Definition (Declaration_Node (Id))) =
3013 N_Constrained_Array_Definition
3015 Set_Related_Array_Object (T, Id);
3016 Set_Related_Array_Object (Base_Type (T), Id);
3019 -- Special checks for protected objects not at library level
3021 if Is_Protected_Type (T)
3022 and then not Is_Library_Level_Entity (Id)
3024 Check_Restriction (No_Local_Protected_Objects, Id);
3026 -- Protected objects with interrupt handlers must be at library level
3028 -- Ada 2005: this test is not needed (and the corresponding clause
3029 -- in the RM is removed) because accessibility checks are sufficient
3030 -- to make handlers not at the library level illegal.
3032 if Has_Interrupt_Handler (T)
3033 and then Ada_Version < Ada_2005
3036 ("interrupt object can only be declared at library level", Id);
3040 -- The actual subtype of the object is the nominal subtype, unless
3041 -- the nominal one is unconstrained and obtained from the expression.
3045 -- The object is in ALFA if-and-only-if its type is in ALFA and it is
3048 if Is_In_ALFA (T) and then not Aliased_Present (N) then
3049 Set_Is_In_ALFA (Id);
3051 Mark_Non_ALFA_Subprogram;
3054 -- These checks should be performed before the initialization expression
3055 -- is considered, so that the Object_Definition node is still the same
3056 -- as in source code.
3058 -- In SPARK, the nominal subtype shall be given by a subtype mark and
3059 -- shall not be unconstrained. (The only exception to this is the
3060 -- admission of declarations of constants of type String.)
3063 Nkind_In (Object_Definition (N), N_Identifier, N_Expanded_Name)
3065 Check_SPARK_Restriction
3066 ("subtype mark required", Object_Definition (N));
3068 elsif Is_Array_Type (T)
3069 and then not Is_Constrained (T)
3070 and then T /= Standard_String
3072 Check_SPARK_Restriction
3073 ("subtype mark of constrained type expected",
3074 Object_Definition (N));
3077 -- There are no aliased objects in SPARK
3079 if Aliased_Present (N) then
3080 Check_SPARK_Restriction ("aliased object is not allowed", N);
3083 -- Process initialization expression if present and not in error
3085 if Present (E) and then E /= Error then
3087 -- Generate an error in case of CPP class-wide object initialization.
3088 -- Required because otherwise the expansion of the class-wide
3089 -- assignment would try to use 'size to initialize the object
3090 -- (primitive that is not available in CPP tagged types).
3092 if Is_Class_Wide_Type (Act_T)
3094 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3096 (Present (Full_View (Root_Type (Etype (Act_T))))
3098 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3101 ("predefined assignment not available for 'C'P'P tagged types",
3105 Mark_Coextensions (N, E);
3108 -- In case of errors detected in the analysis of the expression,
3109 -- decorate it with the expected type to avoid cascaded errors
3111 if No (Etype (E)) then
3115 -- If an initialization expression is present, then we set the
3116 -- Is_True_Constant flag. It will be reset if this is a variable
3117 -- and it is indeed modified.
3119 Set_Is_True_Constant (Id, True);
3121 -- If we are analyzing a constant declaration, set its completion
3122 -- flag after analyzing and resolving the expression.
3124 if Constant_Present (N) then
3125 Set_Has_Completion (Id);
3128 -- Set type and resolve (type may be overridden later on)
3133 -- If E is null and has been replaced by an N_Raise_Constraint_Error
3134 -- node (which was marked already-analyzed), we need to set the type
3135 -- to something other than Any_Access in order to keep gigi happy.
3137 if Etype (E) = Any_Access then
3141 -- If the object is an access to variable, the initialization
3142 -- expression cannot be an access to constant.
3144 if Is_Access_Type (T)
3145 and then not Is_Access_Constant (T)
3146 and then Is_Access_Type (Etype (E))
3147 and then Is_Access_Constant (Etype (E))
3150 ("access to variable cannot be initialized "
3151 & "with an access-to-constant expression", E);
3154 if not Assignment_OK (N) then
3155 Check_Initialization (T, E);
3158 Check_Unset_Reference (E);
3160 -- If this is a variable, then set current value. If this is a
3161 -- declared constant of a scalar type with a static expression,
3162 -- indicate that it is always valid.
3164 if not Constant_Present (N) then
3165 if Compile_Time_Known_Value (E) then
3166 Set_Current_Value (Id, E);
3169 elsif Is_Scalar_Type (T)
3170 and then Is_OK_Static_Expression (E)
3172 Set_Is_Known_Valid (Id);
3175 -- Deal with setting of null flags
3177 if Is_Access_Type (T) then
3178 if Known_Non_Null (E) then
3179 Set_Is_Known_Non_Null (Id, True);
3180 elsif Known_Null (E)
3181 and then not Can_Never_Be_Null (Id)
3183 Set_Is_Known_Null (Id, True);
3187 -- Check incorrect use of dynamically tagged expressions.
3189 if Is_Tagged_Type (T) then
3190 Check_Dynamically_Tagged_Expression
3196 Apply_Scalar_Range_Check (E, T);
3197 Apply_Static_Length_Check (E, T);
3199 if Nkind (Original_Node (N)) = N_Object_Declaration
3200 and then Comes_From_Source (Original_Node (N))
3202 -- Only call test if needed
3204 and then Restriction_Check_Required (SPARK)
3205 and then not Is_SPARK_Initialization_Expr (E)
3207 Check_SPARK_Restriction
3208 ("initialization expression is not appropriate", E);
3212 -- If the No_Streams restriction is set, check that the type of the
3213 -- object is not, and does not contain, any subtype derived from
3214 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
3215 -- Has_Stream just for efficiency reasons. There is no point in
3216 -- spending time on a Has_Stream check if the restriction is not set.
3218 if Restriction_Check_Required (No_Streams) then
3219 if Has_Stream (T) then
3220 Check_Restriction (No_Streams, N);
3224 -- Deal with predicate check before we start to do major rewriting.
3225 -- it is OK to initialize and then check the initialized value, since
3226 -- the object goes out of scope if we get a predicate failure. Note
3227 -- that we do this in the analyzer and not the expander because the
3228 -- analyzer does some substantial rewriting in some cases.
3230 -- We need a predicate check if the type has predicates, and if either
3231 -- there is an initializing expression, or for default initialization
3232 -- when we have at least one case of an explicit default initial value.
3234 if not Suppress_Assignment_Checks (N)
3235 and then Present (Predicate_Function (T))
3239 Is_Partially_Initialized_Type (T, Include_Implicit => False))
3242 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
3245 -- Case of unconstrained type
3247 if Is_Indefinite_Subtype (T) then
3249 -- Nothing to do in deferred constant case
3251 if Constant_Present (N) and then No (E) then
3254 -- Case of no initialization present
3257 if No_Initialization (N) then
3260 elsif Is_Class_Wide_Type (T) then
3262 ("initialization required in class-wide declaration ", N);
3266 ("unconstrained subtype not allowed (need initialization)",
3267 Object_Definition (N));
3269 if Is_Record_Type (T) and then Has_Discriminants (T) then
3271 ("\provide initial value or explicit discriminant values",
3272 Object_Definition (N));
3275 ("\or give default discriminant values for type&",
3276 Object_Definition (N), T);
3278 elsif Is_Array_Type (T) then
3280 ("\provide initial value or explicit array bounds",
3281 Object_Definition (N));
3285 -- Case of initialization present but in error. Set initial
3286 -- expression as absent (but do not make above complaints)
3288 elsif E = Error then
3289 Set_Expression (N, Empty);
3292 -- Case of initialization present
3295 -- Not allowed in Ada 83
3297 if not Constant_Present (N) then
3298 if Ada_Version = Ada_83
3299 and then Comes_From_Source (Object_Definition (N))
3302 ("(Ada 83) unconstrained variable not allowed",
3303 Object_Definition (N));
3307 -- Now we constrain the variable from the initializing expression
3309 -- If the expression is an aggregate, it has been expanded into
3310 -- individual assignments. Retrieve the actual type from the
3311 -- expanded construct.
3313 if Is_Array_Type (T)
3314 and then No_Initialization (N)
3315 and then Nkind (Original_Node (E)) = N_Aggregate
3319 -- In case of class-wide interface object declarations we delay
3320 -- the generation of the equivalent record type declarations until
3321 -- its expansion because there are cases in they are not required.
3323 elsif Is_Interface (T) then
3327 Expand_Subtype_From_Expr (N, T, Object_Definition (N), E);
3328 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
3331 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
3333 if Aliased_Present (N) then
3334 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3337 Freeze_Before (N, Act_T);
3338 Freeze_Before (N, T);
3341 elsif Is_Array_Type (T)
3342 and then No_Initialization (N)
3343 and then Nkind (Original_Node (E)) = N_Aggregate
3345 if not Is_Entity_Name (Object_Definition (N)) then
3347 Check_Compile_Time_Size (Act_T);
3349 if Aliased_Present (N) then
3350 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3354 -- When the given object definition and the aggregate are specified
3355 -- independently, and their lengths might differ do a length check.
3356 -- This cannot happen if the aggregate is of the form (others =>...)
3358 if not Is_Constrained (T) then
3361 elsif Nkind (E) = N_Raise_Constraint_Error then
3363 -- Aggregate is statically illegal. Place back in declaration
3365 Set_Expression (N, E);
3366 Set_No_Initialization (N, False);
3368 elsif T = Etype (E) then
3371 elsif Nkind (E) = N_Aggregate
3372 and then Present (Component_Associations (E))
3373 and then Present (Choices (First (Component_Associations (E))))
3374 and then Nkind (First
3375 (Choices (First (Component_Associations (E))))) = N_Others_Choice
3380 Apply_Length_Check (E, T);
3383 -- If the type is limited unconstrained with defaulted discriminants and
3384 -- there is no expression, then the object is constrained by the
3385 -- defaults, so it is worthwhile building the corresponding subtype.
3387 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
3388 and then not Is_Constrained (T)
3389 and then Has_Discriminants (T)
3392 Act_T := Build_Default_Subtype (T, N);
3394 -- Ada 2005: a limited object may be initialized by means of an
3395 -- aggregate. If the type has default discriminants it has an
3396 -- unconstrained nominal type, Its actual subtype will be obtained
3397 -- from the aggregate, and not from the default discriminants.
3402 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
3404 elsif Present (Underlying_Type (T))
3405 and then not Is_Constrained (Underlying_Type (T))
3406 and then Has_Discriminants (Underlying_Type (T))
3407 and then Nkind (E) = N_Function_Call
3408 and then Constant_Present (N)
3410 -- The back-end has problems with constants of a discriminated type
3411 -- with defaults, if the initial value is a function call. We
3412 -- generate an intermediate temporary for the result of the call.
3413 -- It is unclear why this should make it acceptable to gcc. ???
3415 Remove_Side_Effects (E);
3417 -- If this is a constant declaration of an unconstrained type and
3418 -- the initialization is an aggregate, we can use the subtype of the
3419 -- aggregate for the declared entity because it is immutable.
3421 elsif not Is_Constrained (T)
3422 and then Has_Discriminants (T)
3423 and then Constant_Present (N)
3424 and then not Has_Unchecked_Union (T)
3425 and then Nkind (E) = N_Aggregate
3430 -- Check No_Wide_Characters restriction
3432 Check_Wide_Character_Restriction (T, Object_Definition (N));
3434 -- Indicate this is not set in source. Certainly true for constants, and
3435 -- true for variables so far (will be reset for a variable if and when
3436 -- we encounter a modification in the source).
3438 Set_Never_Set_In_Source (Id, True);
3440 -- Now establish the proper kind and type of the object
3442 if Constant_Present (N) then
3443 Set_Ekind (Id, E_Constant);
3444 Set_Is_True_Constant (Id, True);
3447 Set_Ekind (Id, E_Variable);
3449 -- A variable is set as shared passive if it appears in a shared
3450 -- passive package, and is at the outer level. This is not done for
3451 -- entities generated during expansion, because those are always
3452 -- manipulated locally.
3454 if Is_Shared_Passive (Current_Scope)
3455 and then Is_Library_Level_Entity (Id)
3456 and then Comes_From_Source (Id)
3458 Set_Is_Shared_Passive (Id);
3459 Check_Shared_Var (Id, T, N);
3462 -- Set Has_Initial_Value if initializing expression present. Note
3463 -- that if there is no initializing expression, we leave the state
3464 -- of this flag unchanged (usually it will be False, but notably in
3465 -- the case of exception choice variables, it will already be true).
3468 Set_Has_Initial_Value (Id, True);
3472 -- Initialize alignment and size and capture alignment setting
3474 Init_Alignment (Id);
3476 Set_Optimize_Alignment_Flags (Id);
3478 -- Deal with aliased case
3480 if Aliased_Present (N) then
3481 Set_Is_Aliased (Id);
3483 -- If the object is aliased and the type is unconstrained with
3484 -- defaulted discriminants and there is no expression, then the
3485 -- object is constrained by the defaults, so it is worthwhile
3486 -- building the corresponding subtype.
3488 -- Ada 2005 (AI-363): If the aliased object is discriminated and
3489 -- unconstrained, then only establish an actual subtype if the
3490 -- nominal subtype is indefinite. In definite cases the object is
3491 -- unconstrained in Ada 2005.
3494 and then Is_Record_Type (T)
3495 and then not Is_Constrained (T)
3496 and then Has_Discriminants (T)
3497 and then (Ada_Version < Ada_2005 or else Is_Indefinite_Subtype (T))
3499 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
3503 -- Now we can set the type of the object
3505 Set_Etype (Id, Act_T);
3507 -- Deal with controlled types
3509 if Has_Controlled_Component (Etype (Id))
3510 or else Is_Controlled (Etype (Id))
3512 if not Is_Library_Level_Entity (Id) then
3513 Check_Restriction (No_Nested_Finalization, N);
3515 Validate_Controlled_Object (Id);
3518 -- Generate a warning when an initialization causes an obvious ABE
3519 -- violation. If the init expression is a simple aggregate there
3520 -- shouldn't be any initialize/adjust call generated. This will be
3521 -- true as soon as aggregates are built in place when possible.
3523 -- ??? at the moment we do not generate warnings for temporaries
3524 -- created for those aggregates although Program_Error might be
3525 -- generated if compiled with -gnato.
3527 if Is_Controlled (Etype (Id))
3528 and then Comes_From_Source (Id)
3531 BT : constant Entity_Id := Base_Type (Etype (Id));
3533 Implicit_Call : Entity_Id;
3534 pragma Warnings (Off, Implicit_Call);
3535 -- ??? what is this for (never referenced!)
3537 function Is_Aggr (N : Node_Id) return Boolean;
3538 -- Check that N is an aggregate
3544 function Is_Aggr (N : Node_Id) return Boolean is
3546 case Nkind (Original_Node (N)) is
3547 when N_Aggregate | N_Extension_Aggregate =>
3550 when N_Qualified_Expression |
3552 N_Unchecked_Type_Conversion =>
3553 return Is_Aggr (Expression (Original_Node (N)));
3561 -- If no underlying type, we already are in an error situation.
3562 -- Do not try to add a warning since we do not have access to
3565 if No (Underlying_Type (BT)) then
3566 Implicit_Call := Empty;
3568 -- A generic type does not have usable primitive operators.
3569 -- Initialization calls are built for instances.
3571 elsif Is_Generic_Type (BT) then
3572 Implicit_Call := Empty;
3574 -- If the init expression is not an aggregate, an adjust call
3575 -- will be generated
3577 elsif Present (E) and then not Is_Aggr (E) then
3578 Implicit_Call := Find_Prim_Op (BT, Name_Adjust);
3580 -- If no init expression and we are not in the deferred
3581 -- constant case, an Initialize call will be generated
3583 elsif No (E) and then not Constant_Present (N) then
3584 Implicit_Call := Find_Prim_Op (BT, Name_Initialize);
3587 Implicit_Call := Empty;
3593 if Has_Task (Etype (Id)) then
3594 Check_Restriction (No_Tasking, N);
3596 -- Deal with counting max tasks
3598 -- Nothing to do if inside a generic
3600 if Inside_A_Generic then
3603 -- If library level entity, then count tasks
3605 elsif Is_Library_Level_Entity (Id) then
3606 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
3608 -- If not library level entity, then indicate we don't know max
3609 -- tasks and also check task hierarchy restriction and blocking
3610 -- operation (since starting a task is definitely blocking!)
3613 Check_Restriction (Max_Tasks, N);
3614 Check_Restriction (No_Task_Hierarchy, N);
3615 Check_Potentially_Blocking_Operation (N);
3618 -- A rather specialized test. If we see two tasks being declared
3619 -- of the same type in the same object declaration, and the task
3620 -- has an entry with an address clause, we know that program error
3621 -- will be raised at run time since we can't have two tasks with
3622 -- entries at the same address.
3624 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
3629 E := First_Entity (Etype (Id));
3630 while Present (E) loop
3631 if Ekind (E) = E_Entry
3632 and then Present (Get_Attribute_Definition_Clause
3633 (E, Attribute_Address))
3636 ("?more than one task with same entry address", N);
3638 ("\?Program_Error will be raised at run time", N);
3640 Make_Raise_Program_Error (Loc,
3641 Reason => PE_Duplicated_Entry_Address));
3651 -- Some simple constant-propagation: if the expression is a constant
3652 -- string initialized with a literal, share the literal. This avoids
3656 and then Is_Entity_Name (E)
3657 and then Ekind (Entity (E)) = E_Constant
3658 and then Base_Type (Etype (E)) = Standard_String
3661 Val : constant Node_Id := Constant_Value (Entity (E));
3664 and then Nkind (Val) = N_String_Literal
3666 Rewrite (E, New_Copy (Val));
3671 -- Another optimization: if the nominal subtype is unconstrained and
3672 -- the expression is a function call that returns an unconstrained
3673 -- type, rewrite the declaration as a renaming of the result of the
3674 -- call. The exceptions below are cases where the copy is expected,
3675 -- either by the back end (Aliased case) or by the semantics, as for
3676 -- initializing controlled types or copying tags for classwide types.
3679 and then Nkind (E) = N_Explicit_Dereference
3680 and then Nkind (Original_Node (E)) = N_Function_Call
3681 and then not Is_Library_Level_Entity (Id)
3682 and then not Is_Constrained (Underlying_Type (T))
3683 and then not Is_Aliased (Id)
3684 and then not Is_Class_Wide_Type (T)
3685 and then not Is_Controlled (T)
3686 and then not Has_Controlled_Component (Base_Type (T))
3687 and then Expander_Active
3690 Make_Object_Renaming_Declaration (Loc,
3691 Defining_Identifier => Id,
3692 Access_Definition => Empty,
3693 Subtype_Mark => New_Occurrence_Of
3694 (Base_Type (Etype (Id)), Loc),
3697 Set_Renamed_Object (Id, E);
3699 -- Force generation of debugging information for the constant and for
3700 -- the renamed function call.
3702 Set_Debug_Info_Needed (Id);
3703 Set_Debug_Info_Needed (Entity (Prefix (E)));
3706 if Present (Prev_Entity)
3707 and then Is_Frozen (Prev_Entity)
3708 and then not Error_Posted (Id)
3710 Error_Msg_N ("full constant declaration appears too late", N);
3713 Check_Eliminated (Id);
3715 -- Deal with setting In_Private_Part flag if in private part
3717 if Ekind (Scope (Id)) = E_Package
3718 and then In_Private_Part (Scope (Id))
3720 Set_In_Private_Part (Id);
3723 -- Check for violation of No_Local_Timing_Events
3725 if Restriction_Check_Required (No_Local_Timing_Events)
3726 and then not Is_Library_Level_Entity (Id)
3727 and then Is_RTE (Etype (Id), RE_Timing_Event)
3729 Check_Restriction (No_Local_Timing_Events, N);
3733 if Has_Aspects (N) then
3734 Analyze_Aspect_Specifications (N, Id);
3737 -- Generate 'I' xref for object initialization at definition, only used
3738 -- for the local xref section used in ALFA mode.
3740 if ALFA_Mode and then Present (Expression (Original_Node (N))) then
3741 Generate_Reference (Id, Id, 'I');
3743 end Analyze_Object_Declaration;
3745 ---------------------------
3746 -- Analyze_Others_Choice --
3747 ---------------------------
3749 -- Nothing to do for the others choice node itself, the semantic analysis
3750 -- of the others choice will occur as part of the processing of the parent
3752 procedure Analyze_Others_Choice (N : Node_Id) is
3753 pragma Warnings (Off, N);
3756 end Analyze_Others_Choice;
3758 -------------------------------------------
3759 -- Analyze_Private_Extension_Declaration --
3760 -------------------------------------------
3762 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
3763 T : constant Entity_Id := Defining_Identifier (N);
3764 Indic : constant Node_Id := Subtype_Indication (N);
3765 Parent_Type : Entity_Id;
3766 Parent_Base : Entity_Id;
3769 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
3771 if Is_Non_Empty_List (Interface_List (N)) then
3777 Intf := First (Interface_List (N));
3778 while Present (Intf) loop
3779 T := Find_Type_Of_Subtype_Indic (Intf);
3781 Diagnose_Interface (Intf, T);
3787 Generate_Definition (T);
3789 -- For other than Ada 2012, just enter the name in the current scope
3791 if Ada_Version < Ada_2012 then
3794 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
3795 -- case of private type that completes an incomplete type.
3802 Prev := Find_Type_Name (N);
3804 pragma Assert (Prev = T
3805 or else (Ekind (Prev) = E_Incomplete_Type
3806 and then Present (Full_View (Prev))
3807 and then Full_View (Prev) = T));
3811 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
3812 Parent_Base := Base_Type (Parent_Type);
3814 if Parent_Type = Any_Type
3815 or else Etype (Parent_Type) = Any_Type
3817 Set_Ekind (T, Ekind (Parent_Type));
3818 Set_Etype (T, Any_Type);
3821 elsif not Is_Tagged_Type (Parent_Type) then
3823 ("parent of type extension must be a tagged type ", Indic);
3826 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
3827 Error_Msg_N ("premature derivation of incomplete type", Indic);
3830 elsif Is_Concurrent_Type (Parent_Type) then
3832 ("parent type of a private extension cannot be "
3833 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
3835 Set_Etype (T, Any_Type);
3836 Set_Ekind (T, E_Limited_Private_Type);
3837 Set_Private_Dependents (T, New_Elmt_List);
3838 Set_Error_Posted (T);
3842 -- Perhaps the parent type should be changed to the class-wide type's
3843 -- specific type in this case to prevent cascading errors ???
3845 if Is_Class_Wide_Type (Parent_Type) then
3847 ("parent of type extension must not be a class-wide type", Indic);
3851 if (not Is_Package_Or_Generic_Package (Current_Scope)
3852 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
3853 or else In_Private_Part (Current_Scope)
3856 Error_Msg_N ("invalid context for private extension", N);
3859 -- Set common attributes
3861 Set_Is_Pure (T, Is_Pure (Current_Scope));
3862 Set_Scope (T, Current_Scope);
3863 Set_Ekind (T, E_Record_Type_With_Private);
3864 Init_Size_Align (T);
3866 Set_Etype (T, Parent_Base);
3867 Set_Has_Task (T, Has_Task (Parent_Base));
3869 Set_Convention (T, Convention (Parent_Type));
3870 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
3871 Set_Is_First_Subtype (T);
3872 Make_Class_Wide_Type (T);
3874 if Unknown_Discriminants_Present (N) then
3875 Set_Discriminant_Constraint (T, No_Elist);
3878 Build_Derived_Record_Type (N, Parent_Type, T);
3880 -- Propagate inherited invariant information. The new type has
3881 -- invariants, if the parent type has inheritable invariants,
3882 -- and these invariants can in turn be inherited.
3884 if Has_Inheritable_Invariants (Parent_Type) then
3885 Set_Has_Inheritable_Invariants (T);
3886 Set_Has_Invariants (T);
3889 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
3890 -- synchronized formal derived type.
3892 if Ada_Version >= Ada_2005
3893 and then Synchronized_Present (N)
3895 Set_Is_Limited_Record (T);
3897 -- Formal derived type case
3899 if Is_Generic_Type (T) then
3901 -- The parent must be a tagged limited type or a synchronized
3904 if (not Is_Tagged_Type (Parent_Type)
3905 or else not Is_Limited_Type (Parent_Type))
3907 (not Is_Interface (Parent_Type)
3908 or else not Is_Synchronized_Interface (Parent_Type))
3910 Error_Msg_NE ("parent type of & must be tagged limited " &
3911 "or synchronized", N, T);
3914 -- The progenitors (if any) must be limited or synchronized
3917 if Present (Interfaces (T)) then
3920 Iface_Elmt : Elmt_Id;
3923 Iface_Elmt := First_Elmt (Interfaces (T));
3924 while Present (Iface_Elmt) loop
3925 Iface := Node (Iface_Elmt);
3927 if not Is_Limited_Interface (Iface)
3928 and then not Is_Synchronized_Interface (Iface)
3930 Error_Msg_NE ("progenitor & must be limited " &
3931 "or synchronized", N, Iface);
3934 Next_Elmt (Iface_Elmt);
3939 -- Regular derived extension, the parent must be a limited or
3940 -- synchronized interface.
3943 if not Is_Interface (Parent_Type)
3944 or else (not Is_Limited_Interface (Parent_Type)
3946 not Is_Synchronized_Interface (Parent_Type))
3949 ("parent type of & must be limited interface", N, T);
3953 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
3954 -- extension with a synchronized parent must be explicitly declared
3955 -- synchronized, because the full view will be a synchronized type.
3956 -- This must be checked before the check for limited types below,
3957 -- to ensure that types declared limited are not allowed to extend
3958 -- synchronized interfaces.
3960 elsif Is_Interface (Parent_Type)
3961 and then Is_Synchronized_Interface (Parent_Type)
3962 and then not Synchronized_Present (N)
3965 ("private extension of& must be explicitly synchronized",
3968 elsif Limited_Present (N) then
3969 Set_Is_Limited_Record (T);
3971 if not Is_Limited_Type (Parent_Type)
3973 (not Is_Interface (Parent_Type)
3974 or else not Is_Limited_Interface (Parent_Type))
3976 Error_Msg_NE ("parent type& of limited extension must be limited",
3982 if Has_Aspects (N) then
3983 Analyze_Aspect_Specifications (N, T);
3985 end Analyze_Private_Extension_Declaration;
3987 ---------------------------------
3988 -- Analyze_Subtype_Declaration --
3989 ---------------------------------
3991 procedure Analyze_Subtype_Declaration
3993 Skip : Boolean := False)
3995 Id : constant Entity_Id := Defining_Identifier (N);
3997 R_Checks : Check_Result;
4000 Generate_Definition (Id);
4001 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4002 Init_Size_Align (Id);
4004 -- The following guard condition on Enter_Name is to handle cases where
4005 -- the defining identifier has already been entered into the scope but
4006 -- the declaration as a whole needs to be analyzed.
4008 -- This case in particular happens for derived enumeration types. The
4009 -- derived enumeration type is processed as an inserted enumeration type
4010 -- declaration followed by a rewritten subtype declaration. The defining
4011 -- identifier, however, is entered into the name scope very early in the
4012 -- processing of the original type declaration and therefore needs to be
4013 -- avoided here, when the created subtype declaration is analyzed. (See
4014 -- Build_Derived_Types)
4016 -- This also happens when the full view of a private type is derived
4017 -- type with constraints. In this case the entity has been introduced
4018 -- in the private declaration.
4021 or else (Present (Etype (Id))
4022 and then (Is_Private_Type (Etype (Id))
4023 or else Is_Task_Type (Etype (Id))
4024 or else Is_Rewrite_Substitution (N)))
4032 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4034 -- Inherit common attributes
4036 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4037 Set_Is_Volatile (Id, Is_Volatile (T));
4038 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4039 Set_Is_Atomic (Id, Is_Atomic (T));
4040 Set_Is_Ada_2005_Only (Id, Is_Ada_2005_Only (T));
4041 Set_Is_Ada_2012_Only (Id, Is_Ada_2012_Only (T));
4042 Set_Convention (Id, Convention (T));
4044 -- If ancestor has predicates then so does the subtype, and in addition
4045 -- we must delay the freeze to properly arrange predicate inheritance.
4047 -- The Ancestor_Type test is a big kludge, there seem to be cases in
4048 -- which T = ID, so the above tests and assignments do nothing???
4050 if Has_Predicates (T)
4051 or else (Present (Ancestor_Subtype (T))
4052 and then Has_Predicates (Ancestor_Subtype (T)))
4054 Set_Has_Predicates (Id);
4055 Set_Has_Delayed_Freeze (Id);
4058 -- Subtype of Boolean cannot have a constraint in SPARK
4060 if Is_Boolean_Type (T)
4061 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4063 Check_SPARK_Restriction
4064 ("subtype of Boolean cannot have constraint", N);
4067 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4069 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4075 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4076 One_Cstr := First (Constraints (Cstr));
4077 while Present (One_Cstr) loop
4079 -- Index or discriminant constraint in SPARK must be a
4083 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4085 Check_SPARK_Restriction
4086 ("subtype mark required", One_Cstr);
4088 -- String subtype must have a lower bound of 1 in SPARK.
4089 -- Note that we do not need to test for the non-static case
4090 -- here, since that was already taken care of in
4091 -- Process_Range_Expr_In_Decl.
4093 elsif Base_Type (T) = Standard_String then
4094 Get_Index_Bounds (One_Cstr, Low, High);
4096 if Is_OK_Static_Expression (Low)
4097 and then Expr_Value (Low) /= 1
4099 Check_SPARK_Restriction
4100 ("String subtype must have lower bound of 1", N);
4110 -- In the case where there is no constraint given in the subtype
4111 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4112 -- semantic attributes must be established here.
4114 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
4115 Set_Etype (Id, Base_Type (T));
4117 -- Subtype of unconstrained array without constraint is not allowed
4120 if Is_Array_Type (T)
4121 and then not Is_Constrained (T)
4123 Check_SPARK_Restriction
4124 ("subtype of unconstrained array must have constraint", N);
4129 Set_Ekind (Id, E_Array_Subtype);
4130 Copy_Array_Subtype_Attributes (Id, T);
4132 when Decimal_Fixed_Point_Kind =>
4133 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
4134 Set_Digits_Value (Id, Digits_Value (T));
4135 Set_Delta_Value (Id, Delta_Value (T));
4136 Set_Scale_Value (Id, Scale_Value (T));
4137 Set_Small_Value (Id, Small_Value (T));
4138 Set_Scalar_Range (Id, Scalar_Range (T));
4139 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
4140 Set_Is_Constrained (Id, Is_Constrained (T));
4141 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4142 Set_RM_Size (Id, RM_Size (T));
4144 when Enumeration_Kind =>
4145 Set_Ekind (Id, E_Enumeration_Subtype);
4146 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4147 Set_Scalar_Range (Id, Scalar_Range (T));
4148 Set_Is_Character_Type (Id, Is_Character_Type (T));
4149 Set_Is_Constrained (Id, Is_Constrained (T));
4150 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4151 Set_RM_Size (Id, RM_Size (T));
4153 when Ordinary_Fixed_Point_Kind =>
4154 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4155 Set_Scalar_Range (Id, Scalar_Range (T));
4156 Set_Small_Value (Id, Small_Value (T));
4157 Set_Delta_Value (Id, Delta_Value (T));
4158 Set_Is_Constrained (Id, Is_Constrained (T));
4159 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4160 Set_RM_Size (Id, RM_Size (T));
4163 Set_Ekind (Id, E_Floating_Point_Subtype);
4164 Set_Scalar_Range (Id, Scalar_Range (T));
4165 Set_Digits_Value (Id, Digits_Value (T));
4166 Set_Is_Constrained (Id, Is_Constrained (T));
4168 when Signed_Integer_Kind =>
4169 Set_Ekind (Id, E_Signed_Integer_Subtype);
4170 Set_Scalar_Range (Id, Scalar_Range (T));
4171 Set_Is_Constrained (Id, Is_Constrained (T));
4172 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4173 Set_RM_Size (Id, RM_Size (T));
4175 when Modular_Integer_Kind =>
4176 Set_Ekind (Id, E_Modular_Integer_Subtype);
4177 Set_Scalar_Range (Id, Scalar_Range (T));
4178 Set_Is_Constrained (Id, Is_Constrained (T));
4179 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4180 Set_RM_Size (Id, RM_Size (T));
4182 when Class_Wide_Kind =>
4183 Set_Ekind (Id, E_Class_Wide_Subtype);
4184 Set_First_Entity (Id, First_Entity (T));
4185 Set_Last_Entity (Id, Last_Entity (T));
4186 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4187 Set_Cloned_Subtype (Id, T);
4188 Set_Is_Tagged_Type (Id, True);
4189 Set_Has_Unknown_Discriminants
4192 if Ekind (T) = E_Class_Wide_Subtype then
4193 Set_Equivalent_Type (Id, Equivalent_Type (T));
4196 when E_Record_Type | E_Record_Subtype =>
4197 Set_Ekind (Id, E_Record_Subtype);
4199 if Ekind (T) = E_Record_Subtype
4200 and then Present (Cloned_Subtype (T))
4202 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
4204 Set_Cloned_Subtype (Id, T);
4207 Set_First_Entity (Id, First_Entity (T));
4208 Set_Last_Entity (Id, Last_Entity (T));
4209 Set_Has_Discriminants (Id, Has_Discriminants (T));
4210 Set_Is_Constrained (Id, Is_Constrained (T));
4211 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4212 Set_Has_Unknown_Discriminants
4213 (Id, Has_Unknown_Discriminants (T));
4215 if Has_Discriminants (T) then
4216 Set_Discriminant_Constraint
4217 (Id, Discriminant_Constraint (T));
4218 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4220 elsif Has_Unknown_Discriminants (Id) then
4221 Set_Discriminant_Constraint (Id, No_Elist);
4224 if Is_Tagged_Type (T) then
4225 Set_Is_Tagged_Type (Id);
4226 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4227 Set_Direct_Primitive_Operations
4228 (Id, Direct_Primitive_Operations (T));
4229 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4231 if Is_Interface (T) then
4232 Set_Is_Interface (Id);
4233 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
4237 when Private_Kind =>
4238 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4239 Set_Has_Discriminants (Id, Has_Discriminants (T));
4240 Set_Is_Constrained (Id, Is_Constrained (T));
4241 Set_First_Entity (Id, First_Entity (T));
4242 Set_Last_Entity (Id, Last_Entity (T));
4243 Set_Private_Dependents (Id, New_Elmt_List);
4244 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4245 Set_Has_Unknown_Discriminants
4246 (Id, Has_Unknown_Discriminants (T));
4247 Set_Known_To_Have_Preelab_Init
4248 (Id, Known_To_Have_Preelab_Init (T));
4250 if Is_Tagged_Type (T) then
4251 Set_Is_Tagged_Type (Id);
4252 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4253 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4254 Set_Direct_Primitive_Operations (Id,
4255 Direct_Primitive_Operations (T));
4258 -- In general the attributes of the subtype of a private type
4259 -- are the attributes of the partial view of parent. However,
4260 -- the full view may be a discriminated type, and the subtype
4261 -- must share the discriminant constraint to generate correct
4262 -- calls to initialization procedures.
4264 if Has_Discriminants (T) then
4265 Set_Discriminant_Constraint
4266 (Id, Discriminant_Constraint (T));
4267 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4269 elsif Present (Full_View (T))
4270 and then Has_Discriminants (Full_View (T))
4272 Set_Discriminant_Constraint
4273 (Id, Discriminant_Constraint (Full_View (T)));
4274 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4276 -- This would seem semantically correct, but apparently
4277 -- confuses the back-end. To be explained and checked with
4278 -- current version ???
4280 -- Set_Has_Discriminants (Id);
4283 Prepare_Private_Subtype_Completion (Id, N);
4286 Set_Ekind (Id, E_Access_Subtype);
4287 Set_Is_Constrained (Id, Is_Constrained (T));
4288 Set_Is_Access_Constant
4289 (Id, Is_Access_Constant (T));
4290 Set_Directly_Designated_Type
4291 (Id, Designated_Type (T));
4292 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
4294 -- A Pure library_item must not contain the declaration of a
4295 -- named access type, except within a subprogram, generic
4296 -- subprogram, task unit, or protected unit, or if it has
4297 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
4299 if Comes_From_Source (Id)
4300 and then In_Pure_Unit
4301 and then not In_Subprogram_Task_Protected_Unit
4302 and then not No_Pool_Assigned (Id)
4305 ("named access types not allowed in pure unit", N);
4308 when Concurrent_Kind =>
4309 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4310 Set_Corresponding_Record_Type (Id,
4311 Corresponding_Record_Type (T));
4312 Set_First_Entity (Id, First_Entity (T));
4313 Set_First_Private_Entity (Id, First_Private_Entity (T));
4314 Set_Has_Discriminants (Id, Has_Discriminants (T));
4315 Set_Is_Constrained (Id, Is_Constrained (T));
4316 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4317 Set_Last_Entity (Id, Last_Entity (T));
4319 if Has_Discriminants (T) then
4320 Set_Discriminant_Constraint (Id,
4321 Discriminant_Constraint (T));
4322 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4325 when E_Incomplete_Type =>
4326 if Ada_Version >= Ada_2005 then
4327 Set_Ekind (Id, E_Incomplete_Subtype);
4329 -- Ada 2005 (AI-412): Decorate an incomplete subtype
4330 -- of an incomplete type visible through a limited
4333 if From_With_Type (T)
4334 and then Present (Non_Limited_View (T))
4336 Set_From_With_Type (Id);
4337 Set_Non_Limited_View (Id, Non_Limited_View (T));
4339 -- Ada 2005 (AI-412): Add the regular incomplete subtype
4340 -- to the private dependents of the original incomplete
4341 -- type for future transformation.
4344 Append_Elmt (Id, Private_Dependents (T));
4347 -- If the subtype name denotes an incomplete type an error
4348 -- was already reported by Process_Subtype.
4351 Set_Etype (Id, Any_Type);
4355 raise Program_Error;
4359 if Etype (Id) = Any_Type then
4363 -- Some common processing on all types
4365 Set_Size_Info (Id, T);
4366 Set_First_Rep_Item (Id, First_Rep_Item (T));
4370 Set_Is_Immediately_Visible (Id, True);
4371 Set_Depends_On_Private (Id, Has_Private_Component (T));
4372 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
4374 if Is_Interface (T) then
4375 Set_Is_Interface (Id);
4378 if Present (Generic_Parent_Type (N))
4381 (Parent (Generic_Parent_Type (N))) /= N_Formal_Type_Declaration
4383 (Formal_Type_Definition (Parent (Generic_Parent_Type (N))))
4384 /= N_Formal_Private_Type_Definition)
4386 if Is_Tagged_Type (Id) then
4388 -- If this is a generic actual subtype for a synchronized type,
4389 -- the primitive operations are those of the corresponding record
4390 -- for which there is a separate subtype declaration.
4392 if Is_Concurrent_Type (Id) then
4394 elsif Is_Class_Wide_Type (Id) then
4395 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
4397 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
4400 elsif Scope (Etype (Id)) /= Standard_Standard then
4401 Derive_Subprograms (Generic_Parent_Type (N), Id);
4405 if Is_Private_Type (T)
4406 and then Present (Full_View (T))
4408 Conditional_Delay (Id, Full_View (T));
4410 -- The subtypes of components or subcomponents of protected types
4411 -- do not need freeze nodes, which would otherwise appear in the
4412 -- wrong scope (before the freeze node for the protected type). The
4413 -- proper subtypes are those of the subcomponents of the corresponding
4416 elsif Ekind (Scope (Id)) /= E_Protected_Type
4417 and then Present (Scope (Scope (Id))) -- error defense!
4418 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
4420 Conditional_Delay (Id, T);
4423 -- Check that Constraint_Error is raised for a scalar subtype indication
4424 -- when the lower or upper bound of a non-null range lies outside the
4425 -- range of the type mark.
4427 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4428 if Is_Scalar_Type (Etype (Id))
4429 and then Scalar_Range (Id) /=
4430 Scalar_Range (Etype (Subtype_Mark
4431 (Subtype_Indication (N))))
4435 Etype (Subtype_Mark (Subtype_Indication (N))));
4437 -- In the array case, check compatibility for each index
4439 elsif Is_Array_Type (Etype (Id))
4440 and then Present (First_Index (Id))
4442 -- This really should be a subprogram that finds the indications
4446 Subt_Index : Node_Id := First_Index (Id);
4447 Target_Index : Node_Id :=
4449 (Subtype_Mark (Subtype_Indication (N))));
4450 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
4453 while Present (Subt_Index) loop
4454 if ((Nkind (Subt_Index) = N_Identifier
4455 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
4456 or else Nkind (Subt_Index) = N_Subtype_Indication)
4458 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
4461 Target_Typ : constant Entity_Id :=
4462 Etype (Target_Index);
4466 (Scalar_Range (Etype (Subt_Index)),
4469 Defining_Identifier (N));
4471 -- Reset Has_Dynamic_Range_Check on the subtype to
4472 -- prevent elision of the index check due to a dynamic
4473 -- check generated for a preceding index (needed since
4474 -- Insert_Range_Checks tries to avoid generating
4475 -- redundant checks on a given declaration).
4477 Set_Has_Dynamic_Range_Check (N, False);
4483 Sloc (Defining_Identifier (N)));
4485 -- Record whether this index involved a dynamic check
4488 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
4492 Next_Index (Subt_Index);
4493 Next_Index (Target_Index);
4496 -- Finally, mark whether the subtype involves dynamic checks
4498 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
4503 -- Make sure that generic actual types are properly frozen. The subtype
4504 -- is marked as a generic actual type when the enclosing instance is
4505 -- analyzed, so here we identify the subtype from the tree structure.
4508 and then Is_Generic_Actual_Type (Id)
4509 and then In_Instance
4510 and then not Comes_From_Source (N)
4511 and then Nkind (Subtype_Indication (N)) /= N_Subtype_Indication
4512 and then Is_Frozen (T)
4514 Freeze_Before (N, Id);
4517 Set_Optimize_Alignment_Flags (Id);
4518 Check_Eliminated (Id);
4521 if Has_Aspects (N) then
4522 Analyze_Aspect_Specifications (N, Id);
4524 end Analyze_Subtype_Declaration;
4526 --------------------------------
4527 -- Analyze_Subtype_Indication --
4528 --------------------------------
4530 procedure Analyze_Subtype_Indication (N : Node_Id) is
4531 T : constant Entity_Id := Subtype_Mark (N);
4532 R : constant Node_Id := Range_Expression (Constraint (N));
4539 Set_Etype (N, Etype (R));
4540 Resolve (R, Entity (T));
4542 Set_Error_Posted (R);
4543 Set_Error_Posted (T);
4545 end Analyze_Subtype_Indication;
4547 --------------------------
4548 -- Analyze_Variant_Part --
4549 --------------------------
4551 procedure Analyze_Variant_Part (N : Node_Id) is
4553 procedure Non_Static_Choice_Error (Choice : Node_Id);
4554 -- Error routine invoked by the generic instantiation below when the
4555 -- variant part has a non static choice.
4557 procedure Process_Declarations (Variant : Node_Id);
4558 -- Analyzes all the declarations associated with a Variant. Needed by
4559 -- the generic instantiation below.
4561 package Variant_Choices_Processing is new
4562 Generic_Choices_Processing
4563 (Get_Alternatives => Variants,
4564 Get_Choices => Discrete_Choices,
4565 Process_Empty_Choice => No_OP,
4566 Process_Non_Static_Choice => Non_Static_Choice_Error,
4567 Process_Associated_Node => Process_Declarations);
4568 use Variant_Choices_Processing;
4569 -- Instantiation of the generic choice processing package
4571 -----------------------------
4572 -- Non_Static_Choice_Error --
4573 -----------------------------
4575 procedure Non_Static_Choice_Error (Choice : Node_Id) is
4577 Flag_Non_Static_Expr
4578 ("choice given in variant part is not static!", Choice);
4579 end Non_Static_Choice_Error;
4581 --------------------------
4582 -- Process_Declarations --
4583 --------------------------
4585 procedure Process_Declarations (Variant : Node_Id) is
4587 if not Null_Present (Component_List (Variant)) then
4588 Analyze_Declarations (Component_Items (Component_List (Variant)));
4590 if Present (Variant_Part (Component_List (Variant))) then
4591 Analyze (Variant_Part (Component_List (Variant)));
4594 end Process_Declarations;
4598 Discr_Name : Node_Id;
4599 Discr_Type : Entity_Id;
4601 Dont_Care : Boolean;
4602 Others_Present : Boolean := False;
4604 pragma Warnings (Off, Dont_Care);
4605 pragma Warnings (Off, Others_Present);
4606 -- We don't care about the assigned values of any of these
4608 -- Start of processing for Analyze_Variant_Part
4611 Discr_Name := Name (N);
4612 Analyze (Discr_Name);
4614 -- If Discr_Name bad, get out (prevent cascaded errors)
4616 if Etype (Discr_Name) = Any_Type then
4620 -- Check invalid discriminant in variant part
4622 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
4623 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
4626 Discr_Type := Etype (Entity (Discr_Name));
4628 if not Is_Discrete_Type (Discr_Type) then
4630 ("discriminant in a variant part must be of a discrete type",
4635 -- Call the instantiated Analyze_Choices which does the rest of the work
4637 Analyze_Choices (N, Discr_Type, Dont_Care, Others_Present);
4638 end Analyze_Variant_Part;
4640 ----------------------------
4641 -- Array_Type_Declaration --
4642 ----------------------------
4644 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
4645 Component_Def : constant Node_Id := Component_Definition (Def);
4646 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
4647 Element_Type : Entity_Id;
4648 Implicit_Base : Entity_Id;
4650 Related_Id : Entity_Id := Empty;
4652 P : constant Node_Id := Parent (Def);
4654 T_In_ALFA : Boolean := True;
4657 if Nkind (Def) = N_Constrained_Array_Definition then
4658 Index := First (Discrete_Subtype_Definitions (Def));
4660 Index := First (Subtype_Marks (Def));
4663 -- Find proper names for the implicit types which may be public. In case
4664 -- of anonymous arrays we use the name of the first object of that type
4668 Related_Id := Defining_Identifier (P);
4674 while Present (Index) loop
4677 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
4678 Check_SPARK_Restriction ("subtype mark required", Index);
4681 if Present (Etype (Index))
4682 and then not Is_In_ALFA (Etype (Index))
4687 -- Add a subtype declaration for each index of private array type
4688 -- declaration whose etype is also private. For example:
4691 -- type Index is private;
4693 -- type Table is array (Index) of ...
4696 -- This is currently required by the expander for the internally
4697 -- generated equality subprogram of records with variant parts in
4698 -- which the etype of some component is such private type.
4700 if Ekind (Current_Scope) = E_Package
4701 and then In_Private_Part (Current_Scope)
4702 and then Has_Private_Declaration (Etype (Index))
4705 Loc : constant Source_Ptr := Sloc (Def);
4710 New_E := Make_Temporary (Loc, 'T');
4711 Set_Is_Internal (New_E);
4714 Make_Subtype_Declaration (Loc,
4715 Defining_Identifier => New_E,
4716 Subtype_Indication =>
4717 New_Occurrence_Of (Etype (Index), Loc));
4719 Insert_Before (Parent (Def), Decl);
4721 Set_Etype (Index, New_E);
4723 -- If the index is a range the Entity attribute is not
4724 -- available. Example:
4727 -- type T is private;
4729 -- type T is new Natural;
4730 -- Table : array (T(1) .. T(10)) of Boolean;
4733 if Nkind (Index) /= N_Range then
4734 Set_Entity (Index, New_E);
4739 Make_Index (Index, P, Related_Id, Nb_Index);
4741 -- Check error of subtype with predicate for index type
4743 Bad_Predicated_Subtype_Use
4744 ("subtype& has predicate, not allowed as index subtype",
4745 Index, Etype (Index));
4747 -- Move to next index
4750 Nb_Index := Nb_Index + 1;
4753 -- Process subtype indication if one is present
4755 if Present (Component_Typ) then
4756 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
4758 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
4759 Check_SPARK_Restriction ("subtype mark required", Component_Typ);
4762 if Present (Element_Type)
4763 and then not Is_In_ALFA (Element_Type)
4768 -- Ada 2005 (AI-230): Access Definition case
4770 else pragma Assert (Present (Access_Definition (Component_Def)));
4774 -- Indicate that the anonymous access type is created by the
4775 -- array type declaration.
4777 Element_Type := Access_Definition
4779 N => Access_Definition (Component_Def));
4780 Set_Is_Local_Anonymous_Access (Element_Type);
4782 -- Propagate the parent. This field is needed if we have to generate
4783 -- the master_id associated with an anonymous access to task type
4784 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
4786 Set_Parent (Element_Type, Parent (T));
4788 -- Ada 2005 (AI-230): In case of components that are anonymous access
4789 -- types the level of accessibility depends on the enclosing type
4792 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
4794 -- Ada 2005 (AI-254)
4797 CD : constant Node_Id :=
4798 Access_To_Subprogram_Definition
4799 (Access_Definition (Component_Def));
4801 if Present (CD) and then Protected_Present (CD) then
4803 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
4808 -- Constrained array case
4811 T := Create_Itype (E_Void, P, Related_Id, 'T');
4814 if Nkind (Def) = N_Constrained_Array_Definition then
4816 -- Establish Implicit_Base as unconstrained base type
4818 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
4820 Set_Etype (Implicit_Base, Implicit_Base);
4821 Set_Scope (Implicit_Base, Current_Scope);
4822 Set_Has_Delayed_Freeze (Implicit_Base);
4824 -- The constrained array type is a subtype of the unconstrained one
4826 Set_Ekind (T, E_Array_Subtype);
4827 Init_Size_Align (T);
4828 Set_Etype (T, Implicit_Base);
4829 Set_Scope (T, Current_Scope);
4830 Set_Is_Constrained (T, True);
4831 Set_First_Index (T, First (Discrete_Subtype_Definitions (Def)));
4832 Set_Has_Delayed_Freeze (T);
4834 -- Complete setup of implicit base type
4836 Set_First_Index (Implicit_Base, First_Index (T));
4837 Set_Component_Type (Implicit_Base, Element_Type);
4838 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
4839 Set_Component_Size (Implicit_Base, Uint_0);
4840 Set_Packed_Array_Type (Implicit_Base, Empty);
4841 Set_Has_Controlled_Component
4842 (Implicit_Base, Has_Controlled_Component
4844 or else Is_Controlled
4846 Set_Finalize_Storage_Only
4847 (Implicit_Base, Finalize_Storage_Only
4850 -- Final check for static bounds on array
4852 if not Has_Static_Array_Bounds (T) then
4856 -- Unconstrained array case
4859 Set_Ekind (T, E_Array_Type);
4860 Init_Size_Align (T);
4862 Set_Scope (T, Current_Scope);
4863 Set_Component_Size (T, Uint_0);
4864 Set_Is_Constrained (T, False);
4865 Set_First_Index (T, First (Subtype_Marks (Def)));
4866 Set_Has_Delayed_Freeze (T, True);
4867 Set_Has_Task (T, Has_Task (Element_Type));
4868 Set_Has_Controlled_Component (T, Has_Controlled_Component
4871 Is_Controlled (Element_Type));
4872 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
4876 -- Common attributes for both cases
4878 Set_Component_Type (Base_Type (T), Element_Type);
4879 Set_Packed_Array_Type (T, Empty);
4880 Set_Is_In_ALFA (T, T_In_ALFA);
4882 if Aliased_Present (Component_Definition (Def)) then
4883 Check_SPARK_Restriction
4884 ("aliased is not allowed", Component_Definition (Def));
4885 Set_Has_Aliased_Components (Etype (T));
4888 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
4889 -- array type to ensure that objects of this type are initialized.
4891 if Ada_Version >= Ada_2005
4892 and then Can_Never_Be_Null (Element_Type)
4894 Set_Can_Never_Be_Null (T);
4896 if Null_Exclusion_Present (Component_Definition (Def))
4898 -- No need to check itypes because in their case this check was
4899 -- done at their point of creation
4901 and then not Is_Itype (Element_Type)
4904 ("`NOT NULL` not allowed (null already excluded)",
4905 Subtype_Indication (Component_Definition (Def)));
4909 Priv := Private_Component (Element_Type);
4911 if Present (Priv) then
4913 -- Check for circular definitions
4915 if Priv = Any_Type then
4916 Set_Component_Type (Etype (T), Any_Type);
4918 -- There is a gap in the visibility of operations on the composite
4919 -- type only if the component type is defined in a different scope.
4921 elsif Scope (Priv) = Current_Scope then
4924 elsif Is_Limited_Type (Priv) then
4925 Set_Is_Limited_Composite (Etype (T));
4926 Set_Is_Limited_Composite (T);
4928 Set_Is_Private_Composite (Etype (T));
4929 Set_Is_Private_Composite (T);
4933 -- A syntax error in the declaration itself may lead to an empty index
4934 -- list, in which case do a minimal patch.
4936 if No (First_Index (T)) then
4937 Error_Msg_N ("missing index definition in array type declaration", T);
4940 Indexes : constant List_Id :=
4941 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
4943 Set_Discrete_Subtype_Definitions (Def, Indexes);
4944 Set_First_Index (T, First (Indexes));
4949 -- Create a concatenation operator for the new type. Internal array
4950 -- types created for packed entities do not need such, they are
4951 -- compatible with the user-defined type.
4953 if Number_Dimensions (T) = 1
4954 and then not Is_Packed_Array_Type (T)
4956 New_Concatenation_Op (T);
4959 -- In the case of an unconstrained array the parser has already verified
4960 -- that all the indexes are unconstrained but we still need to make sure
4961 -- that the element type is constrained.
4963 if Is_Indefinite_Subtype (Element_Type) then
4965 ("unconstrained element type in array declaration",
4966 Subtype_Indication (Component_Def));
4968 elsif Is_Abstract_Type (Element_Type) then
4970 ("the type of a component cannot be abstract",
4971 Subtype_Indication (Component_Def));
4973 end Array_Type_Declaration;
4975 ------------------------------------------------------
4976 -- Replace_Anonymous_Access_To_Protected_Subprogram --
4977 ------------------------------------------------------
4979 function Replace_Anonymous_Access_To_Protected_Subprogram
4980 (N : Node_Id) return Entity_Id
4982 Loc : constant Source_Ptr := Sloc (N);
4984 Curr_Scope : constant Scope_Stack_Entry :=
4985 Scope_Stack.Table (Scope_Stack.Last);
4987 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
4994 Set_Is_Internal (Anon);
4997 when N_Component_Declaration |
4998 N_Unconstrained_Array_Definition |
4999 N_Constrained_Array_Definition =>
5000 Comp := Component_Definition (N);
5001 Acc := Access_Definition (Comp);
5003 when N_Discriminant_Specification =>
5004 Comp := Discriminant_Type (N);
5007 when N_Parameter_Specification =>
5008 Comp := Parameter_Type (N);
5011 when N_Access_Function_Definition =>
5012 Comp := Result_Definition (N);
5015 when N_Object_Declaration =>
5016 Comp := Object_Definition (N);
5019 when N_Function_Specification =>
5020 Comp := Result_Definition (N);
5024 raise Program_Error;
5027 Decl := Make_Full_Type_Declaration (Loc,
5028 Defining_Identifier => Anon,
5030 Copy_Separate_Tree (Access_To_Subprogram_Definition (Acc)));
5032 Mark_Rewrite_Insertion (Decl);
5034 -- Insert the new declaration in the nearest enclosing scope. If the
5035 -- node is a body and N is its return type, the declaration belongs in
5036 -- the enclosing scope.
5040 if Nkind (P) = N_Subprogram_Body
5041 and then Nkind (N) = N_Function_Specification
5046 while Present (P) and then not Has_Declarations (P) loop
5050 pragma Assert (Present (P));
5052 if Nkind (P) = N_Package_Specification then
5053 Prepend (Decl, Visible_Declarations (P));
5055 Prepend (Decl, Declarations (P));
5058 -- Replace the anonymous type with an occurrence of the new declaration.
5059 -- In all cases the rewritten node does not have the null-exclusion
5060 -- attribute because (if present) it was already inherited by the
5061 -- anonymous entity (Anon). Thus, in case of components we do not
5062 -- inherit this attribute.
5064 if Nkind (N) = N_Parameter_Specification then
5065 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5066 Set_Etype (Defining_Identifier (N), Anon);
5067 Set_Null_Exclusion_Present (N, False);
5069 elsif Nkind (N) = N_Object_Declaration then
5070 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5071 Set_Etype (Defining_Identifier (N), Anon);
5073 elsif Nkind (N) = N_Access_Function_Definition then
5074 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5076 elsif Nkind (N) = N_Function_Specification then
5077 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5078 Set_Etype (Defining_Unit_Name (N), Anon);
5082 Make_Component_Definition (Loc,
5083 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
5086 Mark_Rewrite_Insertion (Comp);
5088 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition) then
5092 -- Temporarily remove the current scope (record or subprogram) from
5093 -- the stack to add the new declarations to the enclosing scope.
5095 Scope_Stack.Decrement_Last;
5097 Set_Is_Itype (Anon);
5098 Scope_Stack.Append (Curr_Scope);
5101 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
5102 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
5104 end Replace_Anonymous_Access_To_Protected_Subprogram;
5106 -------------------------------
5107 -- Build_Derived_Access_Type --
5108 -------------------------------
5110 procedure Build_Derived_Access_Type
5112 Parent_Type : Entity_Id;
5113 Derived_Type : Entity_Id)
5115 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
5117 Desig_Type : Entity_Id;
5119 Discr_Con_Elist : Elist_Id;
5120 Discr_Con_El : Elmt_Id;
5124 -- Set the designated type so it is available in case this is an access
5125 -- to a self-referential type, e.g. a standard list type with a next
5126 -- pointer. Will be reset after subtype is built.
5128 Set_Directly_Designated_Type
5129 (Derived_Type, Designated_Type (Parent_Type));
5131 Subt := Process_Subtype (S, N);
5133 if Nkind (S) /= N_Subtype_Indication
5134 and then Subt /= Base_Type (Subt)
5136 Set_Ekind (Derived_Type, E_Access_Subtype);
5139 if Ekind (Derived_Type) = E_Access_Subtype then
5141 Pbase : constant Entity_Id := Base_Type (Parent_Type);
5142 Ibase : constant Entity_Id :=
5143 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
5144 Svg_Chars : constant Name_Id := Chars (Ibase);
5145 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
5148 Copy_Node (Pbase, Ibase);
5150 Set_Chars (Ibase, Svg_Chars);
5151 Set_Next_Entity (Ibase, Svg_Next_E);
5152 Set_Sloc (Ibase, Sloc (Derived_Type));
5153 Set_Scope (Ibase, Scope (Derived_Type));
5154 Set_Freeze_Node (Ibase, Empty);
5155 Set_Is_Frozen (Ibase, False);
5156 Set_Comes_From_Source (Ibase, False);
5157 Set_Is_First_Subtype (Ibase, False);
5159 Set_Etype (Ibase, Pbase);
5160 Set_Etype (Derived_Type, Ibase);
5164 Set_Directly_Designated_Type
5165 (Derived_Type, Designated_Type (Subt));
5167 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
5168 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
5169 Set_Size_Info (Derived_Type, Parent_Type);
5170 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
5171 Set_Depends_On_Private (Derived_Type,
5172 Has_Private_Component (Derived_Type));
5173 Conditional_Delay (Derived_Type, Subt);
5175 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
5176 -- that it is not redundant.
5178 if Null_Exclusion_Present (Type_Definition (N)) then
5179 Set_Can_Never_Be_Null (Derived_Type);
5181 if Can_Never_Be_Null (Parent_Type)
5185 ("`NOT NULL` not allowed (& already excludes null)",
5189 elsif Can_Never_Be_Null (Parent_Type) then
5190 Set_Can_Never_Be_Null (Derived_Type);
5193 -- Note: we do not copy the Storage_Size_Variable, since we always go to
5194 -- the root type for this information.
5196 -- Apply range checks to discriminants for derived record case
5197 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
5199 Desig_Type := Designated_Type (Derived_Type);
5200 if Is_Composite_Type (Desig_Type)
5201 and then (not Is_Array_Type (Desig_Type))
5202 and then Has_Discriminants (Desig_Type)
5203 and then Base_Type (Desig_Type) /= Desig_Type
5205 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
5206 Discr_Con_El := First_Elmt (Discr_Con_Elist);
5208 Discr := First_Discriminant (Base_Type (Desig_Type));
5209 while Present (Discr_Con_El) loop
5210 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
5211 Next_Elmt (Discr_Con_El);
5212 Next_Discriminant (Discr);
5215 end Build_Derived_Access_Type;
5217 ------------------------------
5218 -- Build_Derived_Array_Type --
5219 ------------------------------
5221 procedure Build_Derived_Array_Type
5223 Parent_Type : Entity_Id;
5224 Derived_Type : Entity_Id)
5226 Loc : constant Source_Ptr := Sloc (N);
5227 Tdef : constant Node_Id := Type_Definition (N);
5228 Indic : constant Node_Id := Subtype_Indication (Tdef);
5229 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5230 Implicit_Base : Entity_Id;
5231 New_Indic : Node_Id;
5233 procedure Make_Implicit_Base;
5234 -- If the parent subtype is constrained, the derived type is a subtype
5235 -- of an implicit base type derived from the parent base.
5237 ------------------------
5238 -- Make_Implicit_Base --
5239 ------------------------
5241 procedure Make_Implicit_Base is
5244 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5246 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5247 Set_Etype (Implicit_Base, Parent_Base);
5249 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
5250 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
5252 Set_Has_Delayed_Freeze (Implicit_Base, True);
5253 end Make_Implicit_Base;
5255 -- Start of processing for Build_Derived_Array_Type
5258 if not Is_Constrained (Parent_Type) then
5259 if Nkind (Indic) /= N_Subtype_Indication then
5260 Set_Ekind (Derived_Type, E_Array_Type);
5262 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5263 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
5265 Set_Has_Delayed_Freeze (Derived_Type, True);
5269 Set_Etype (Derived_Type, Implicit_Base);
5272 Make_Subtype_Declaration (Loc,
5273 Defining_Identifier => Derived_Type,
5274 Subtype_Indication =>
5275 Make_Subtype_Indication (Loc,
5276 Subtype_Mark => New_Reference_To (Implicit_Base, Loc),
5277 Constraint => Constraint (Indic)));
5279 Rewrite (N, New_Indic);
5284 if Nkind (Indic) /= N_Subtype_Indication then
5287 Set_Ekind (Derived_Type, Ekind (Parent_Type));
5288 Set_Etype (Derived_Type, Implicit_Base);
5289 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5292 Error_Msg_N ("illegal constraint on constrained type", Indic);
5296 -- If parent type is not a derived type itself, and is declared in
5297 -- closed scope (e.g. a subprogram), then we must explicitly introduce
5298 -- the new type's concatenation operator since Derive_Subprograms
5299 -- will not inherit the parent's operator. If the parent type is
5300 -- unconstrained, the operator is of the unconstrained base type.
5302 if Number_Dimensions (Parent_Type) = 1
5303 and then not Is_Limited_Type (Parent_Type)
5304 and then not Is_Derived_Type (Parent_Type)
5305 and then not Is_Package_Or_Generic_Package
5306 (Scope (Base_Type (Parent_Type)))
5308 if not Is_Constrained (Parent_Type)
5309 and then Is_Constrained (Derived_Type)
5311 New_Concatenation_Op (Implicit_Base);
5313 New_Concatenation_Op (Derived_Type);
5316 end Build_Derived_Array_Type;
5318 -----------------------------------
5319 -- Build_Derived_Concurrent_Type --
5320 -----------------------------------
5322 procedure Build_Derived_Concurrent_Type
5324 Parent_Type : Entity_Id;
5325 Derived_Type : Entity_Id)
5327 Loc : constant Source_Ptr := Sloc (N);
5329 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
5330 Corr_Decl : Node_Id;
5331 Corr_Decl_Needed : Boolean;
5332 -- If the derived type has fewer discriminants than its parent, the
5333 -- corresponding record is also a derived type, in order to account for
5334 -- the bound discriminants. We create a full type declaration for it in
5337 Constraint_Present : constant Boolean :=
5338 Nkind (Subtype_Indication (Type_Definition (N))) =
5339 N_Subtype_Indication;
5341 D_Constraint : Node_Id;
5342 New_Constraint : Elist_Id;
5343 Old_Disc : Entity_Id;
5344 New_Disc : Entity_Id;
5348 Set_Stored_Constraint (Derived_Type, No_Elist);
5349 Corr_Decl_Needed := False;
5352 if Present (Discriminant_Specifications (N))
5353 and then Constraint_Present
5355 Old_Disc := First_Discriminant (Parent_Type);
5356 New_Disc := First (Discriminant_Specifications (N));
5357 while Present (New_Disc) and then Present (Old_Disc) loop
5358 Next_Discriminant (Old_Disc);
5363 if Present (Old_Disc) and then Expander_Active then
5365 -- The new type has fewer discriminants, so we need to create a new
5366 -- corresponding record, which is derived from the corresponding
5367 -- record of the parent, and has a stored constraint that captures
5368 -- the values of the discriminant constraints. The corresponding
5369 -- record is needed only if expander is active and code generation is
5372 -- The type declaration for the derived corresponding record has the
5373 -- same discriminant part and constraints as the current declaration.
5374 -- Copy the unanalyzed tree to build declaration.
5376 Corr_Decl_Needed := True;
5377 New_N := Copy_Separate_Tree (N);
5380 Make_Full_Type_Declaration (Loc,
5381 Defining_Identifier => Corr_Record,
5382 Discriminant_Specifications =>
5383 Discriminant_Specifications (New_N),
5385 Make_Derived_Type_Definition (Loc,
5386 Subtype_Indication =>
5387 Make_Subtype_Indication (Loc,
5390 (Corresponding_Record_Type (Parent_Type), Loc),
5393 (Subtype_Indication (Type_Definition (New_N))))));
5396 -- Copy Storage_Size and Relative_Deadline variables if task case
5398 if Is_Task_Type (Parent_Type) then
5399 Set_Storage_Size_Variable (Derived_Type,
5400 Storage_Size_Variable (Parent_Type));
5401 Set_Relative_Deadline_Variable (Derived_Type,
5402 Relative_Deadline_Variable (Parent_Type));
5405 if Present (Discriminant_Specifications (N)) then
5406 Push_Scope (Derived_Type);
5407 Check_Or_Process_Discriminants (N, Derived_Type);
5409 if Constraint_Present then
5411 Expand_To_Stored_Constraint
5413 Build_Discriminant_Constraints
5415 Subtype_Indication (Type_Definition (N)), True));
5420 elsif Constraint_Present then
5422 -- Build constrained subtype and derive from it
5425 Loc : constant Source_Ptr := Sloc (N);
5426 Anon : constant Entity_Id :=
5427 Make_Defining_Identifier (Loc,
5428 Chars => New_External_Name (Chars (Derived_Type), 'T'));
5433 Make_Subtype_Declaration (Loc,
5434 Defining_Identifier => Anon,
5435 Subtype_Indication =>
5436 Subtype_Indication (Type_Definition (N)));
5437 Insert_Before (N, Decl);
5440 Rewrite (Subtype_Indication (Type_Definition (N)),
5441 New_Occurrence_Of (Anon, Loc));
5442 Set_Analyzed (Derived_Type, False);
5448 -- By default, operations and private data are inherited from parent.
5449 -- However, in the presence of bound discriminants, a new corresponding
5450 -- record will be created, see below.
5452 Set_Has_Discriminants
5453 (Derived_Type, Has_Discriminants (Parent_Type));
5454 Set_Corresponding_Record_Type
5455 (Derived_Type, Corresponding_Record_Type (Parent_Type));
5457 -- Is_Constrained is set according the parent subtype, but is set to
5458 -- False if the derived type is declared with new discriminants.
5462 (Is_Constrained (Parent_Type) or else Constraint_Present)
5463 and then not Present (Discriminant_Specifications (N)));
5465 if Constraint_Present then
5466 if not Has_Discriminants (Parent_Type) then
5467 Error_Msg_N ("untagged parent must have discriminants", N);
5469 elsif Present (Discriminant_Specifications (N)) then
5471 -- Verify that new discriminants are used to constrain old ones
5476 (Constraint (Subtype_Indication (Type_Definition (N)))));
5478 Old_Disc := First_Discriminant (Parent_Type);
5480 while Present (D_Constraint) loop
5481 if Nkind (D_Constraint) /= N_Discriminant_Association then
5483 -- Positional constraint. If it is a reference to a new
5484 -- discriminant, it constrains the corresponding old one.
5486 if Nkind (D_Constraint) = N_Identifier then
5487 New_Disc := First_Discriminant (Derived_Type);
5488 while Present (New_Disc) loop
5489 exit when Chars (New_Disc) = Chars (D_Constraint);
5490 Next_Discriminant (New_Disc);
5493 if Present (New_Disc) then
5494 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
5498 Next_Discriminant (Old_Disc);
5500 -- if this is a named constraint, search by name for the old
5501 -- discriminants constrained by the new one.
5503 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
5505 -- Find new discriminant with that name
5507 New_Disc := First_Discriminant (Derived_Type);
5508 while Present (New_Disc) loop
5510 Chars (New_Disc) = Chars (Expression (D_Constraint));
5511 Next_Discriminant (New_Disc);
5514 if Present (New_Disc) then
5516 -- Verify that new discriminant renames some discriminant
5517 -- of the parent type, and associate the new discriminant
5518 -- with one or more old ones that it renames.
5524 Selector := First (Selector_Names (D_Constraint));
5525 while Present (Selector) loop
5526 Old_Disc := First_Discriminant (Parent_Type);
5527 while Present (Old_Disc) loop
5528 exit when Chars (Old_Disc) = Chars (Selector);
5529 Next_Discriminant (Old_Disc);
5532 if Present (Old_Disc) then
5533 Set_Corresponding_Discriminant
5534 (New_Disc, Old_Disc);
5543 Next (D_Constraint);
5546 New_Disc := First_Discriminant (Derived_Type);
5547 while Present (New_Disc) loop
5548 if No (Corresponding_Discriminant (New_Disc)) then
5550 ("new discriminant& must constrain old one", N, New_Disc);
5553 Subtypes_Statically_Compatible
5555 Etype (Corresponding_Discriminant (New_Disc)))
5558 ("& not statically compatible with parent discriminant",
5562 Next_Discriminant (New_Disc);
5566 elsif Present (Discriminant_Specifications (N)) then
5568 ("missing discriminant constraint in untagged derivation", N);
5571 -- The entity chain of the derived type includes the new discriminants
5572 -- but shares operations with the parent.
5574 if Present (Discriminant_Specifications (N)) then
5575 Old_Disc := First_Discriminant (Parent_Type);
5576 while Present (Old_Disc) loop
5577 if No (Next_Entity (Old_Disc))
5578 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
5581 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
5585 Next_Discriminant (Old_Disc);
5589 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
5590 if Has_Discriminants (Parent_Type) then
5591 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5592 Set_Discriminant_Constraint (
5593 Derived_Type, Discriminant_Constraint (Parent_Type));
5597 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
5599 Set_Has_Completion (Derived_Type);
5601 if Corr_Decl_Needed then
5602 Set_Stored_Constraint (Derived_Type, New_Constraint);
5603 Insert_After (N, Corr_Decl);
5604 Analyze (Corr_Decl);
5605 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
5607 end Build_Derived_Concurrent_Type;
5609 ------------------------------------
5610 -- Build_Derived_Enumeration_Type --
5611 ------------------------------------
5613 procedure Build_Derived_Enumeration_Type
5615 Parent_Type : Entity_Id;
5616 Derived_Type : Entity_Id)
5618 Loc : constant Source_Ptr := Sloc (N);
5619 Def : constant Node_Id := Type_Definition (N);
5620 Indic : constant Node_Id := Subtype_Indication (Def);
5621 Implicit_Base : Entity_Id;
5622 Literal : Entity_Id;
5623 New_Lit : Entity_Id;
5624 Literals_List : List_Id;
5625 Type_Decl : Node_Id;
5627 Rang_Expr : Node_Id;
5630 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
5631 -- not have explicit literals lists we need to process types derived
5632 -- from them specially. This is handled by Derived_Standard_Character.
5633 -- If the parent type is a generic type, there are no literals either,
5634 -- and we construct the same skeletal representation as for the generic
5637 if Is_Standard_Character_Type (Parent_Type) then
5638 Derived_Standard_Character (N, Parent_Type, Derived_Type);
5640 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
5646 if Nkind (Indic) /= N_Subtype_Indication then
5648 Make_Attribute_Reference (Loc,
5649 Attribute_Name => Name_First,
5650 Prefix => New_Reference_To (Derived_Type, Loc));
5651 Set_Etype (Lo, Derived_Type);
5654 Make_Attribute_Reference (Loc,
5655 Attribute_Name => Name_Last,
5656 Prefix => New_Reference_To (Derived_Type, Loc));
5657 Set_Etype (Hi, Derived_Type);
5659 Set_Scalar_Range (Derived_Type,
5665 -- Analyze subtype indication and verify compatibility
5666 -- with parent type.
5668 if Base_Type (Process_Subtype (Indic, N)) /=
5669 Base_Type (Parent_Type)
5672 ("illegal constraint for formal discrete type", N);
5678 -- If a constraint is present, analyze the bounds to catch
5679 -- premature usage of the derived literals.
5681 if Nkind (Indic) = N_Subtype_Indication
5682 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
5684 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
5685 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
5688 -- Introduce an implicit base type for the derived type even if there
5689 -- is no constraint attached to it, since this seems closer to the
5690 -- Ada semantics. Build a full type declaration tree for the derived
5691 -- type using the implicit base type as the defining identifier. The
5692 -- build a subtype declaration tree which applies the constraint (if
5693 -- any) have it replace the derived type declaration.
5695 Literal := First_Literal (Parent_Type);
5696 Literals_List := New_List;
5697 while Present (Literal)
5698 and then Ekind (Literal) = E_Enumeration_Literal
5700 -- Literals of the derived type have the same representation as
5701 -- those of the parent type, but this representation can be
5702 -- overridden by an explicit representation clause. Indicate
5703 -- that there is no explicit representation given yet. These
5704 -- derived literals are implicit operations of the new type,
5705 -- and can be overridden by explicit ones.
5707 if Nkind (Literal) = N_Defining_Character_Literal then
5709 Make_Defining_Character_Literal (Loc, Chars (Literal));
5711 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
5714 Set_Ekind (New_Lit, E_Enumeration_Literal);
5715 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
5716 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
5717 Set_Enumeration_Rep_Expr (New_Lit, Empty);
5718 Set_Alias (New_Lit, Literal);
5719 Set_Is_Known_Valid (New_Lit, True);
5721 Append (New_Lit, Literals_List);
5722 Next_Literal (Literal);
5726 Make_Defining_Identifier (Sloc (Derived_Type),
5727 Chars => New_External_Name (Chars (Derived_Type), 'B'));
5729 -- Indicate the proper nature of the derived type. This must be done
5730 -- before analysis of the literals, to recognize cases when a literal
5731 -- may be hidden by a previous explicit function definition (cf.
5734 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
5735 Set_Etype (Derived_Type, Implicit_Base);
5738 Make_Full_Type_Declaration (Loc,
5739 Defining_Identifier => Implicit_Base,
5740 Discriminant_Specifications => No_List,
5742 Make_Enumeration_Type_Definition (Loc, Literals_List));
5744 Mark_Rewrite_Insertion (Type_Decl);
5745 Insert_Before (N, Type_Decl);
5746 Analyze (Type_Decl);
5748 -- After the implicit base is analyzed its Etype needs to be changed
5749 -- to reflect the fact that it is derived from the parent type which
5750 -- was ignored during analysis. We also set the size at this point.
5752 Set_Etype (Implicit_Base, Parent_Type);
5754 Set_Size_Info (Implicit_Base, Parent_Type);
5755 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
5756 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
5758 -- Copy other flags from parent type
5760 Set_Has_Non_Standard_Rep
5761 (Implicit_Base, Has_Non_Standard_Rep
5763 Set_Has_Pragma_Ordered
5764 (Implicit_Base, Has_Pragma_Ordered
5766 Set_Has_Delayed_Freeze (Implicit_Base);
5768 -- Process the subtype indication including a validation check on the
5769 -- constraint, if any. If a constraint is given, its bounds must be
5770 -- implicitly converted to the new type.
5772 if Nkind (Indic) = N_Subtype_Indication then
5774 R : constant Node_Id :=
5775 Range_Expression (Constraint (Indic));
5778 if Nkind (R) = N_Range then
5779 Hi := Build_Scalar_Bound
5780 (High_Bound (R), Parent_Type, Implicit_Base);
5781 Lo := Build_Scalar_Bound
5782 (Low_Bound (R), Parent_Type, Implicit_Base);
5785 -- Constraint is a Range attribute. Replace with explicit
5786 -- mention of the bounds of the prefix, which must be a
5789 Analyze (Prefix (R));
5791 Convert_To (Implicit_Base,
5792 Make_Attribute_Reference (Loc,
5793 Attribute_Name => Name_Last,
5795 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
5798 Convert_To (Implicit_Base,
5799 Make_Attribute_Reference (Loc,
5800 Attribute_Name => Name_First,
5802 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
5809 (Type_High_Bound (Parent_Type),
5810 Parent_Type, Implicit_Base);
5813 (Type_Low_Bound (Parent_Type),
5814 Parent_Type, Implicit_Base);
5822 -- If we constructed a default range for the case where no range
5823 -- was given, then the expressions in the range must not freeze
5824 -- since they do not correspond to expressions in the source.
5826 if Nkind (Indic) /= N_Subtype_Indication then
5827 Set_Must_Not_Freeze (Lo);
5828 Set_Must_Not_Freeze (Hi);
5829 Set_Must_Not_Freeze (Rang_Expr);
5833 Make_Subtype_Declaration (Loc,
5834 Defining_Identifier => Derived_Type,
5835 Subtype_Indication =>
5836 Make_Subtype_Indication (Loc,
5837 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
5839 Make_Range_Constraint (Loc,
5840 Range_Expression => Rang_Expr))));
5844 -- If pragma Discard_Names applies on the first subtype of the parent
5845 -- type, then it must be applied on this subtype as well.
5847 if Einfo.Discard_Names (First_Subtype (Parent_Type)) then
5848 Set_Discard_Names (Derived_Type);
5851 -- Apply a range check. Since this range expression doesn't have an
5852 -- Etype, we have to specifically pass the Source_Typ parameter. Is
5855 if Nkind (Indic) = N_Subtype_Indication then
5856 Apply_Range_Check (Range_Expression (Constraint (Indic)),
5858 Source_Typ => Entity (Subtype_Mark (Indic)));
5861 end Build_Derived_Enumeration_Type;
5863 --------------------------------
5864 -- Build_Derived_Numeric_Type --
5865 --------------------------------
5867 procedure Build_Derived_Numeric_Type
5869 Parent_Type : Entity_Id;
5870 Derived_Type : Entity_Id)
5872 Loc : constant Source_Ptr := Sloc (N);
5873 Tdef : constant Node_Id := Type_Definition (N);
5874 Indic : constant Node_Id := Subtype_Indication (Tdef);
5875 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5876 No_Constraint : constant Boolean := Nkind (Indic) /=
5877 N_Subtype_Indication;
5878 Implicit_Base : Entity_Id;
5884 -- Process the subtype indication including a validation check on
5885 -- the constraint if any.
5887 Discard_Node (Process_Subtype (Indic, N));
5889 -- Introduce an implicit base type for the derived type even if there
5890 -- is no constraint attached to it, since this seems closer to the Ada
5894 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5896 Set_Etype (Implicit_Base, Parent_Base);
5897 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5898 Set_Size_Info (Implicit_Base, Parent_Base);
5899 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
5900 Set_Parent (Implicit_Base, Parent (Derived_Type));
5901 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
5903 -- Set RM Size for discrete type or decimal fixed-point type
5904 -- Ordinary fixed-point is excluded, why???
5906 if Is_Discrete_Type (Parent_Base)
5907 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
5909 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
5912 Set_Has_Delayed_Freeze (Implicit_Base);
5914 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
5915 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
5917 Set_Scalar_Range (Implicit_Base,
5922 if Has_Infinities (Parent_Base) then
5923 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
5926 -- The Derived_Type, which is the entity of the declaration, is a
5927 -- subtype of the implicit base. Its Ekind is a subtype, even in the
5928 -- absence of an explicit constraint.
5930 Set_Etype (Derived_Type, Implicit_Base);
5932 -- If we did not have a constraint, then the Ekind is set from the
5933 -- parent type (otherwise Process_Subtype has set the bounds)
5935 if No_Constraint then
5936 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
5939 -- If we did not have a range constraint, then set the range from the
5940 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
5943 or else not Has_Range_Constraint (Indic)
5945 Set_Scalar_Range (Derived_Type,
5947 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
5948 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
5949 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5951 if Has_Infinities (Parent_Type) then
5952 Set_Includes_Infinities (Scalar_Range (Derived_Type));
5955 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
5958 Set_Is_Descendent_Of_Address (Derived_Type,
5959 Is_Descendent_Of_Address (Parent_Type));
5960 Set_Is_Descendent_Of_Address (Implicit_Base,
5961 Is_Descendent_Of_Address (Parent_Type));
5963 -- Set remaining type-specific fields, depending on numeric type
5965 if Is_Modular_Integer_Type (Parent_Type) then
5966 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
5968 Set_Non_Binary_Modulus
5969 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
5972 (Implicit_Base, Is_Known_Valid (Parent_Base));
5974 elsif Is_Floating_Point_Type (Parent_Type) then
5976 -- Digits of base type is always copied from the digits value of
5977 -- the parent base type, but the digits of the derived type will
5978 -- already have been set if there was a constraint present.
5980 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
5981 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
5983 if No_Constraint then
5984 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
5987 elsif Is_Fixed_Point_Type (Parent_Type) then
5989 -- Small of base type and derived type are always copied from the
5990 -- parent base type, since smalls never change. The delta of the
5991 -- base type is also copied from the parent base type. However the
5992 -- delta of the derived type will have been set already if a
5993 -- constraint was present.
5995 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
5996 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
5997 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
5999 if No_Constraint then
6000 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
6003 -- The scale and machine radix in the decimal case are always
6004 -- copied from the parent base type.
6006 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
6007 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
6008 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
6010 Set_Machine_Radix_10
6011 (Derived_Type, Machine_Radix_10 (Parent_Base));
6012 Set_Machine_Radix_10
6013 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6015 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6017 if No_Constraint then
6018 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6021 -- the analysis of the subtype_indication sets the
6022 -- digits value of the derived type.
6029 -- The type of the bounds is that of the parent type, and they
6030 -- must be converted to the derived type.
6032 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
6034 -- The implicit_base should be frozen when the derived type is frozen,
6035 -- but note that it is used in the conversions of the bounds. For fixed
6036 -- types we delay the determination of the bounds until the proper
6037 -- freezing point. For other numeric types this is rejected by GCC, for
6038 -- reasons that are currently unclear (???), so we choose to freeze the
6039 -- implicit base now. In the case of integers and floating point types
6040 -- this is harmless because subsequent representation clauses cannot
6041 -- affect anything, but it is still baffling that we cannot use the
6042 -- same mechanism for all derived numeric types.
6044 -- There is a further complication: actually *some* representation
6045 -- clauses can affect the implicit base type. Namely, attribute
6046 -- definition clauses for stream-oriented attributes need to set the
6047 -- corresponding TSS entries on the base type, and this normally cannot
6048 -- be done after the base type is frozen, so the circuitry in
6049 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility and
6050 -- not use Set_TSS in this case.
6052 if Is_Fixed_Point_Type (Parent_Type) then
6053 Conditional_Delay (Implicit_Base, Parent_Type);
6055 Freeze_Before (N, Implicit_Base);
6057 end Build_Derived_Numeric_Type;
6059 --------------------------------
6060 -- Build_Derived_Private_Type --
6061 --------------------------------
6063 procedure Build_Derived_Private_Type
6065 Parent_Type : Entity_Id;
6066 Derived_Type : Entity_Id;
6067 Is_Completion : Boolean;
6068 Derive_Subps : Boolean := True)
6070 Loc : constant Source_Ptr := Sloc (N);
6071 Der_Base : Entity_Id;
6073 Full_Decl : Node_Id := Empty;
6074 Full_Der : Entity_Id;
6076 Last_Discr : Entity_Id;
6077 Par_Scope : constant Entity_Id := Scope (Base_Type (Parent_Type));
6078 Swapped : Boolean := False;
6080 procedure Copy_And_Build;
6081 -- Copy derived type declaration, replace parent with its full view,
6082 -- and analyze new declaration.
6084 --------------------
6085 -- Copy_And_Build --
6086 --------------------
6088 procedure Copy_And_Build is
6092 if Ekind (Parent_Type) in Record_Kind
6094 (Ekind (Parent_Type) in Enumeration_Kind
6095 and then not Is_Standard_Character_Type (Parent_Type)
6096 and then not Is_Generic_Type (Root_Type (Parent_Type)))
6098 Full_N := New_Copy_Tree (N);
6099 Insert_After (N, Full_N);
6100 Build_Derived_Type (
6101 Full_N, Parent_Type, Full_Der, True, Derive_Subps => False);
6104 Build_Derived_Type (
6105 N, Parent_Type, Full_Der, True, Derive_Subps => False);
6109 -- Start of processing for Build_Derived_Private_Type
6112 if Is_Tagged_Type (Parent_Type) then
6113 Full_P := Full_View (Parent_Type);
6115 -- A type extension of a type with unknown discriminants is an
6116 -- indefinite type that the back-end cannot handle directly.
6117 -- We treat it as a private type, and build a completion that is
6118 -- derived from the full view of the parent, and hopefully has
6119 -- known discriminants.
6121 -- If the full view of the parent type has an underlying record view,
6122 -- use it to generate the underlying record view of this derived type
6123 -- (required for chains of derivations with unknown discriminants).
6125 -- Minor optimization: we avoid the generation of useless underlying
6126 -- record view entities if the private type declaration has unknown
6127 -- discriminants but its corresponding full view has no
6130 if Has_Unknown_Discriminants (Parent_Type)
6131 and then Present (Full_P)
6132 and then (Has_Discriminants (Full_P)
6133 or else Present (Underlying_Record_View (Full_P)))
6134 and then not In_Open_Scopes (Par_Scope)
6135 and then Expander_Active
6138 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
6139 New_Ext : constant Node_Id :=
6141 (Record_Extension_Part (Type_Definition (N)));
6145 Build_Derived_Record_Type
6146 (N, Parent_Type, Derived_Type, Derive_Subps);
6148 -- Build anonymous completion, as a derivation from the full
6149 -- view of the parent. This is not a completion in the usual
6150 -- sense, because the current type is not private.
6153 Make_Full_Type_Declaration (Loc,
6154 Defining_Identifier => Full_Der,
6156 Make_Derived_Type_Definition (Loc,
6157 Subtype_Indication =>
6159 (Subtype_Indication (Type_Definition (N))),
6160 Record_Extension_Part => New_Ext));
6162 -- If the parent type has an underlying record view, use it
6163 -- here to build the new underlying record view.
6165 if Present (Underlying_Record_View (Full_P)) then
6167 (Nkind (Subtype_Indication (Type_Definition (Decl)))
6169 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
6170 Underlying_Record_View (Full_P));
6173 Install_Private_Declarations (Par_Scope);
6174 Install_Visible_Declarations (Par_Scope);
6175 Insert_Before (N, Decl);
6177 -- Mark entity as an underlying record view before analysis,
6178 -- to avoid generating the list of its primitive operations
6179 -- (which is not really required for this entity) and thus
6180 -- prevent spurious errors associated with missing overriding
6181 -- of abstract primitives (overridden only for Derived_Type).
6183 Set_Ekind (Full_Der, E_Record_Type);
6184 Set_Is_Underlying_Record_View (Full_Der);
6188 pragma Assert (Has_Discriminants (Full_Der)
6189 and then not Has_Unknown_Discriminants (Full_Der));
6191 Uninstall_Declarations (Par_Scope);
6193 -- Freeze the underlying record view, to prevent generation of
6194 -- useless dispatching information, which is simply shared with
6195 -- the real derived type.
6197 Set_Is_Frozen (Full_Der);
6199 -- Set up links between real entity and underlying record view
6201 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
6202 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
6205 -- If discriminants are known, build derived record
6208 Build_Derived_Record_Type
6209 (N, Parent_Type, Derived_Type, Derive_Subps);
6214 elsif Has_Discriminants (Parent_Type) then
6215 if Present (Full_View (Parent_Type)) then
6216 if not Is_Completion then
6218 -- Copy declaration for subsequent analysis, to provide a
6219 -- completion for what is a private declaration. Indicate that
6220 -- the full type is internally generated.
6222 Full_Decl := New_Copy_Tree (N);
6223 Full_Der := New_Copy (Derived_Type);
6224 Set_Comes_From_Source (Full_Decl, False);
6225 Set_Comes_From_Source (Full_Der, False);
6226 Set_Parent (Full_Der, Full_Decl);
6228 Insert_After (N, Full_Decl);
6231 -- If this is a completion, the full view being built is itself
6232 -- private. We build a subtype of the parent with the same
6233 -- constraints as this full view, to convey to the back end the
6234 -- constrained components and the size of this subtype. If the
6235 -- parent is constrained, its full view can serve as the
6236 -- underlying full view of the derived type.
6238 if No (Discriminant_Specifications (N)) then
6239 if Nkind (Subtype_Indication (Type_Definition (N))) =
6240 N_Subtype_Indication
6242 Build_Underlying_Full_View (N, Derived_Type, Parent_Type);
6244 elsif Is_Constrained (Full_View (Parent_Type)) then
6245 Set_Underlying_Full_View
6246 (Derived_Type, Full_View (Parent_Type));
6250 -- If there are new discriminants, the parent subtype is
6251 -- constrained by them, but it is not clear how to build
6252 -- the Underlying_Full_View in this case???
6259 -- Build partial view of derived type from partial view of parent
6261 Build_Derived_Record_Type
6262 (N, Parent_Type, Derived_Type, Derive_Subps);
6264 if Present (Full_View (Parent_Type)) and then not Is_Completion then
6265 if not In_Open_Scopes (Par_Scope)
6266 or else not In_Same_Source_Unit (N, Parent_Type)
6268 -- Swap partial and full views temporarily
6270 Install_Private_Declarations (Par_Scope);
6271 Install_Visible_Declarations (Par_Scope);
6275 -- Build full view of derived type from full view of parent which
6276 -- is now installed. Subprograms have been derived on the partial
6277 -- view, the completion does not derive them anew.
6279 if not Is_Tagged_Type (Parent_Type) then
6281 -- If the parent is itself derived from another private type,
6282 -- installing the private declarations has not affected its
6283 -- privacy status, so use its own full view explicitly.
6285 if Is_Private_Type (Parent_Type) then
6286 Build_Derived_Record_Type
6287 (Full_Decl, Full_View (Parent_Type), Full_Der, False);
6289 Build_Derived_Record_Type
6290 (Full_Decl, Parent_Type, Full_Der, False);
6294 -- If full view of parent is tagged, the completion inherits
6295 -- the proper primitive operations.
6297 Set_Defining_Identifier (Full_Decl, Full_Der);
6298 Build_Derived_Record_Type
6299 (Full_Decl, Parent_Type, Full_Der, Derive_Subps);
6302 -- The full declaration has been introduced into the tree and
6303 -- processed in the step above. It should not be analyzed again
6304 -- (when encountered later in the current list of declarations)
6305 -- to prevent spurious name conflicts. The full entity remains
6308 Set_Analyzed (Full_Decl);
6311 Uninstall_Declarations (Par_Scope);
6313 if In_Open_Scopes (Par_Scope) then
6314 Install_Visible_Declarations (Par_Scope);
6318 Der_Base := Base_Type (Derived_Type);
6319 Set_Full_View (Derived_Type, Full_Der);
6320 Set_Full_View (Der_Base, Base_Type (Full_Der));
6322 -- Copy the discriminant list from full view to the partial views
6323 -- (base type and its subtype). Gigi requires that the partial and
6324 -- full views have the same discriminants.
6326 -- Note that since the partial view is pointing to discriminants
6327 -- in the full view, their scope will be that of the full view.
6328 -- This might cause some front end problems and need adjustment???
6330 Discr := First_Discriminant (Base_Type (Full_Der));
6331 Set_First_Entity (Der_Base, Discr);
6334 Last_Discr := Discr;
6335 Next_Discriminant (Discr);
6336 exit when No (Discr);
6339 Set_Last_Entity (Der_Base, Last_Discr);
6341 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
6342 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
6343 Set_Stored_Constraint (Full_Der, Stored_Constraint (Derived_Type));
6346 -- If this is a completion, the derived type stays private and
6347 -- there is no need to create a further full view, except in the
6348 -- unusual case when the derivation is nested within a child unit,
6354 elsif Present (Full_View (Parent_Type))
6355 and then Has_Discriminants (Full_View (Parent_Type))
6357 if Has_Unknown_Discriminants (Parent_Type)
6358 and then Nkind (Subtype_Indication (Type_Definition (N))) =
6359 N_Subtype_Indication
6362 ("cannot constrain type with unknown discriminants",
6363 Subtype_Indication (Type_Definition (N)));
6367 -- If full view of parent is a record type, build full view as a
6368 -- derivation from the parent's full view. Partial view remains
6369 -- private. For code generation and linking, the full view must have
6370 -- the same public status as the partial one. This full view is only
6371 -- needed if the parent type is in an enclosing scope, so that the
6372 -- full view may actually become visible, e.g. in a child unit. This
6373 -- is both more efficient, and avoids order of freezing problems with
6374 -- the added entities.
6376 if not Is_Private_Type (Full_View (Parent_Type))
6377 and then (In_Open_Scopes (Scope (Parent_Type)))
6380 Make_Defining_Identifier
6381 (Sloc (Derived_Type), Chars (Derived_Type));
6382 Set_Is_Itype (Full_Der);
6383 Set_Has_Private_Declaration (Full_Der);
6384 Set_Has_Private_Declaration (Derived_Type);
6385 Set_Associated_Node_For_Itype (Full_Der, N);
6386 Set_Parent (Full_Der, Parent (Derived_Type));
6387 Set_Full_View (Derived_Type, Full_Der);
6388 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
6389 Full_P := Full_View (Parent_Type);
6390 Exchange_Declarations (Parent_Type);
6392 Exchange_Declarations (Full_P);
6395 Build_Derived_Record_Type
6396 (N, Full_View (Parent_Type), Derived_Type,
6397 Derive_Subps => False);
6400 -- In any case, the primitive operations are inherited from the
6401 -- parent type, not from the internal full view.
6403 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
6405 if Derive_Subps then
6406 Derive_Subprograms (Parent_Type, Derived_Type);
6410 -- Untagged type, No discriminants on either view
6412 if Nkind (Subtype_Indication (Type_Definition (N))) =
6413 N_Subtype_Indication
6416 ("illegal constraint on type without discriminants", N);
6419 if Present (Discriminant_Specifications (N))
6420 and then Present (Full_View (Parent_Type))
6421 and then not Is_Tagged_Type (Full_View (Parent_Type))
6423 Error_Msg_N ("cannot add discriminants to untagged type", N);
6426 Set_Stored_Constraint (Derived_Type, No_Elist);
6427 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6428 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
6429 Set_Has_Controlled_Component
6430 (Derived_Type, Has_Controlled_Component
6433 -- Direct controlled types do not inherit Finalize_Storage_Only flag
6435 if not Is_Controlled (Parent_Type) then
6436 Set_Finalize_Storage_Only
6437 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
6440 -- Construct the implicit full view by deriving from full view of the
6441 -- parent type. In order to get proper visibility, we install the
6442 -- parent scope and its declarations.
6444 -- ??? If the parent is untagged private and its completion is
6445 -- tagged, this mechanism will not work because we cannot derive from
6446 -- the tagged full view unless we have an extension.
6448 if Present (Full_View (Parent_Type))
6449 and then not Is_Tagged_Type (Full_View (Parent_Type))
6450 and then not Is_Completion
6453 Make_Defining_Identifier
6454 (Sloc (Derived_Type), Chars (Derived_Type));
6455 Set_Is_Itype (Full_Der);
6456 Set_Has_Private_Declaration (Full_Der);
6457 Set_Has_Private_Declaration (Derived_Type);
6458 Set_Associated_Node_For_Itype (Full_Der, N);
6459 Set_Parent (Full_Der, Parent (Derived_Type));
6460 Set_Full_View (Derived_Type, Full_Der);
6462 if not In_Open_Scopes (Par_Scope) then
6463 Install_Private_Declarations (Par_Scope);
6464 Install_Visible_Declarations (Par_Scope);
6466 Uninstall_Declarations (Par_Scope);
6468 -- If parent scope is open and in another unit, and parent has a
6469 -- completion, then the derivation is taking place in the visible
6470 -- part of a child unit. In that case retrieve the full view of
6471 -- the parent momentarily.
6473 elsif not In_Same_Source_Unit (N, Parent_Type) then
6474 Full_P := Full_View (Parent_Type);
6475 Exchange_Declarations (Parent_Type);
6477 Exchange_Declarations (Full_P);
6479 -- Otherwise it is a local derivation
6485 Set_Scope (Full_Der, Current_Scope);
6486 Set_Is_First_Subtype (Full_Der,
6487 Is_First_Subtype (Derived_Type));
6488 Set_Has_Size_Clause (Full_Der, False);
6489 Set_Has_Alignment_Clause (Full_Der, False);
6490 Set_Next_Entity (Full_Der, Empty);
6491 Set_Has_Delayed_Freeze (Full_Der);
6492 Set_Is_Frozen (Full_Der, False);
6493 Set_Freeze_Node (Full_Der, Empty);
6494 Set_Depends_On_Private (Full_Der,
6495 Has_Private_Component (Full_Der));
6496 Set_Public_Status (Full_Der);
6500 Set_Has_Unknown_Discriminants (Derived_Type,
6501 Has_Unknown_Discriminants (Parent_Type));
6503 if Is_Private_Type (Derived_Type) then
6504 Set_Private_Dependents (Derived_Type, New_Elmt_List);
6507 if Is_Private_Type (Parent_Type)
6508 and then Base_Type (Parent_Type) = Parent_Type
6509 and then In_Open_Scopes (Scope (Parent_Type))
6511 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
6513 if Is_Child_Unit (Scope (Current_Scope))
6514 and then Is_Completion
6515 and then In_Private_Part (Current_Scope)
6516 and then Scope (Parent_Type) /= Current_Scope
6518 -- This is the unusual case where a type completed by a private
6519 -- derivation occurs within a package nested in a child unit, and
6520 -- the parent is declared in an ancestor. In this case, the full
6521 -- view of the parent type will become visible in the body of
6522 -- the enclosing child, and only then will the current type be
6523 -- possibly non-private. We build a underlying full view that
6524 -- will be installed when the enclosing child body is compiled.
6527 Make_Defining_Identifier
6528 (Sloc (Derived_Type), Chars (Derived_Type));
6529 Set_Is_Itype (Full_Der);
6530 Build_Itype_Reference (Full_Der, N);
6532 -- The full view will be used to swap entities on entry/exit to
6533 -- the body, and must appear in the entity list for the package.
6535 Append_Entity (Full_Der, Scope (Derived_Type));
6536 Set_Has_Private_Declaration (Full_Der);
6537 Set_Has_Private_Declaration (Derived_Type);
6538 Set_Associated_Node_For_Itype (Full_Der, N);
6539 Set_Parent (Full_Der, Parent (Derived_Type));
6540 Full_P := Full_View (Parent_Type);
6541 Exchange_Declarations (Parent_Type);
6543 Exchange_Declarations (Full_P);
6544 Set_Underlying_Full_View (Derived_Type, Full_Der);
6547 end Build_Derived_Private_Type;
6549 -------------------------------
6550 -- Build_Derived_Record_Type --
6551 -------------------------------
6555 -- Ideally we would like to use the same model of type derivation for
6556 -- tagged and untagged record types. Unfortunately this is not quite
6557 -- possible because the semantics of representation clauses is different
6558 -- for tagged and untagged records under inheritance. Consider the
6561 -- type R (...) is [tagged] record ... end record;
6562 -- type T (...) is new R (...) [with ...];
6564 -- The representation clauses for T can specify a completely different
6565 -- record layout from R's. Hence the same component can be placed in two
6566 -- very different positions in objects of type T and R. If R and T are
6567 -- tagged types, representation clauses for T can only specify the layout
6568 -- of non inherited components, thus components that are common in R and T
6569 -- have the same position in objects of type R and T.
6571 -- This has two implications. The first is that the entire tree for R's
6572 -- declaration needs to be copied for T in the untagged case, so that T
6573 -- can be viewed as a record type of its own with its own representation
6574 -- clauses. The second implication is the way we handle discriminants.
6575 -- Specifically, in the untagged case we need a way to communicate to Gigi
6576 -- what are the real discriminants in the record, while for the semantics
6577 -- we need to consider those introduced by the user to rename the
6578 -- discriminants in the parent type. This is handled by introducing the
6579 -- notion of stored discriminants. See below for more.
6581 -- Fortunately the way regular components are inherited can be handled in
6582 -- the same way in tagged and untagged types.
6584 -- To complicate things a bit more the private view of a private extension
6585 -- cannot be handled in the same way as the full view (for one thing the
6586 -- semantic rules are somewhat different). We will explain what differs
6589 -- 2. DISCRIMINANTS UNDER INHERITANCE
6591 -- The semantic rules governing the discriminants of derived types are
6594 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
6595 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
6597 -- If parent type has discriminants, then the discriminants that are
6598 -- declared in the derived type are [3.4 (11)]:
6600 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
6603 -- o Otherwise, each discriminant of the parent type (implicitly declared
6604 -- in the same order with the same specifications). In this case, the
6605 -- discriminants are said to be "inherited", or if unknown in the parent
6606 -- are also unknown in the derived type.
6608 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
6610 -- o The parent subtype shall be constrained;
6612 -- o If the parent type is not a tagged type, then each discriminant of
6613 -- the derived type shall be used in the constraint defining a parent
6614 -- subtype. [Implementation note: This ensures that the new discriminant
6615 -- can share storage with an existing discriminant.]
6617 -- For the derived type each discriminant of the parent type is either
6618 -- inherited, constrained to equal some new discriminant of the derived
6619 -- type, or constrained to the value of an expression.
6621 -- When inherited or constrained to equal some new discriminant, the
6622 -- parent discriminant and the discriminant of the derived type are said
6625 -- If a discriminant of the parent type is constrained to a specific value
6626 -- in the derived type definition, then the discriminant is said to be
6627 -- "specified" by that derived type definition.
6629 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
6631 -- We have spoken about stored discriminants in point 1 (introduction)
6632 -- above. There are two sort of stored discriminants: implicit and
6633 -- explicit. As long as the derived type inherits the same discriminants as
6634 -- the root record type, stored discriminants are the same as regular
6635 -- discriminants, and are said to be implicit. However, if any discriminant
6636 -- in the root type was renamed in the derived type, then the derived
6637 -- type will contain explicit stored discriminants. Explicit stored
6638 -- discriminants are discriminants in addition to the semantically visible
6639 -- discriminants defined for the derived type. Stored discriminants are
6640 -- used by Gigi to figure out what are the physical discriminants in
6641 -- objects of the derived type (see precise definition in einfo.ads).
6642 -- As an example, consider the following:
6644 -- type R (D1, D2, D3 : Int) is record ... end record;
6645 -- type T1 is new R;
6646 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
6647 -- type T3 is new T2;
6648 -- type T4 (Y : Int) is new T3 (Y, 99);
6650 -- The following table summarizes the discriminants and stored
6651 -- discriminants in R and T1 through T4.
6653 -- Type Discrim Stored Discrim Comment
6654 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
6655 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
6656 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
6657 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
6658 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
6660 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
6661 -- find the corresponding discriminant in the parent type, while
6662 -- Original_Record_Component (abbreviated ORC below), the actual physical
6663 -- component that is renamed. Finally the field Is_Completely_Hidden
6664 -- (abbreviated ICH below) is set for all explicit stored discriminants
6665 -- (see einfo.ads for more info). For the above example this gives:
6667 -- Discrim CD ORC ICH
6668 -- ^^^^^^^ ^^ ^^^ ^^^
6669 -- D1 in R empty itself no
6670 -- D2 in R empty itself no
6671 -- D3 in R empty itself no
6673 -- D1 in T1 D1 in R itself no
6674 -- D2 in T1 D2 in R itself no
6675 -- D3 in T1 D3 in R itself no
6677 -- X1 in T2 D3 in T1 D3 in T2 no
6678 -- X2 in T2 D1 in T1 D1 in T2 no
6679 -- D1 in T2 empty itself yes
6680 -- D2 in T2 empty itself yes
6681 -- D3 in T2 empty itself yes
6683 -- X1 in T3 X1 in T2 D3 in T3 no
6684 -- X2 in T3 X2 in T2 D1 in T3 no
6685 -- D1 in T3 empty itself yes
6686 -- D2 in T3 empty itself yes
6687 -- D3 in T3 empty itself yes
6689 -- Y in T4 X1 in T3 D3 in T3 no
6690 -- D1 in T3 empty itself yes
6691 -- D2 in T3 empty itself yes
6692 -- D3 in T3 empty itself yes
6694 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
6696 -- Type derivation for tagged types is fairly straightforward. If no
6697 -- discriminants are specified by the derived type, these are inherited
6698 -- from the parent. No explicit stored discriminants are ever necessary.
6699 -- The only manipulation that is done to the tree is that of adding a
6700 -- _parent field with parent type and constrained to the same constraint
6701 -- specified for the parent in the derived type definition. For instance:
6703 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
6704 -- type T1 is new R with null record;
6705 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
6707 -- are changed into:
6709 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
6710 -- _parent : R (D1, D2, D3);
6713 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
6714 -- _parent : T1 (X2, 88, X1);
6717 -- The discriminants actually present in R, T1 and T2 as well as their CD,
6718 -- ORC and ICH fields are:
6720 -- Discrim CD ORC ICH
6721 -- ^^^^^^^ ^^ ^^^ ^^^
6722 -- D1 in R empty itself no
6723 -- D2 in R empty itself no
6724 -- D3 in R empty itself no
6726 -- D1 in T1 D1 in R D1 in R no
6727 -- D2 in T1 D2 in R D2 in R no
6728 -- D3 in T1 D3 in R D3 in R no
6730 -- X1 in T2 D3 in T1 D3 in R no
6731 -- X2 in T2 D1 in T1 D1 in R no
6733 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
6735 -- Regardless of whether we dealing with a tagged or untagged type
6736 -- we will transform all derived type declarations of the form
6738 -- type T is new R (...) [with ...];
6740 -- subtype S is R (...);
6741 -- type T is new S [with ...];
6743 -- type BT is new R [with ...];
6744 -- subtype T is BT (...);
6746 -- That is, the base derived type is constrained only if it has no
6747 -- discriminants. The reason for doing this is that GNAT's semantic model
6748 -- assumes that a base type with discriminants is unconstrained.
6750 -- Note that, strictly speaking, the above transformation is not always
6751 -- correct. Consider for instance the following excerpt from ACVC b34011a:
6753 -- procedure B34011A is
6754 -- type REC (D : integer := 0) is record
6759 -- type T6 is new Rec;
6760 -- function F return T6;
6765 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
6768 -- The definition of Q6.U is illegal. However transforming Q6.U into
6770 -- type BaseU is new T6;
6771 -- subtype U is BaseU (Q6.F.I)
6773 -- turns U into a legal subtype, which is incorrect. To avoid this problem
6774 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
6775 -- the transformation described above.
6777 -- There is another instance where the above transformation is incorrect.
6781 -- type Base (D : Integer) is tagged null record;
6782 -- procedure P (X : Base);
6784 -- type Der is new Base (2) with null record;
6785 -- procedure P (X : Der);
6788 -- Then the above transformation turns this into
6790 -- type Der_Base is new Base with null record;
6791 -- -- procedure P (X : Base) is implicitly inherited here
6792 -- -- as procedure P (X : Der_Base).
6794 -- subtype Der is Der_Base (2);
6795 -- procedure P (X : Der);
6796 -- -- The overriding of P (X : Der_Base) is illegal since we
6797 -- -- have a parameter conformance problem.
6799 -- To get around this problem, after having semantically processed Der_Base
6800 -- and the rewritten subtype declaration for Der, we copy Der_Base field
6801 -- Discriminant_Constraint from Der so that when parameter conformance is
6802 -- checked when P is overridden, no semantic errors are flagged.
6804 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
6806 -- Regardless of whether we are dealing with a tagged or untagged type
6807 -- we will transform all derived type declarations of the form
6809 -- type R (D1, .., Dn : ...) is [tagged] record ...;
6810 -- type T is new R [with ...];
6812 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
6814 -- The reason for such transformation is that it allows us to implement a
6815 -- very clean form of component inheritance as explained below.
6817 -- Note that this transformation is not achieved by direct tree rewriting
6818 -- and manipulation, but rather by redoing the semantic actions that the
6819 -- above transformation will entail. This is done directly in routine
6820 -- Inherit_Components.
6822 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
6824 -- In both tagged and untagged derived types, regular non discriminant
6825 -- components are inherited in the derived type from the parent type. In
6826 -- the absence of discriminants component, inheritance is straightforward
6827 -- as components can simply be copied from the parent.
6829 -- If the parent has discriminants, inheriting components constrained with
6830 -- these discriminants requires caution. Consider the following example:
6832 -- type R (D1, D2 : Positive) is [tagged] record
6833 -- S : String (D1 .. D2);
6836 -- type T1 is new R [with null record];
6837 -- type T2 (X : positive) is new R (1, X) [with null record];
6839 -- As explained in 6. above, T1 is rewritten as
6840 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
6841 -- which makes the treatment for T1 and T2 identical.
6843 -- What we want when inheriting S, is that references to D1 and D2 in R are
6844 -- replaced with references to their correct constraints, i.e. D1 and D2 in
6845 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
6846 -- with either discriminant references in the derived type or expressions.
6847 -- This replacement is achieved as follows: before inheriting R's
6848 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
6849 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
6850 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
6851 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
6852 -- by String (1 .. X).
6854 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
6856 -- We explain here the rules governing private type extensions relevant to
6857 -- type derivation. These rules are explained on the following example:
6859 -- type D [(...)] is new A [(...)] with private; <-- partial view
6860 -- type D [(...)] is new P [(...)] with null record; <-- full view
6862 -- Type A is called the ancestor subtype of the private extension.
6863 -- Type P is the parent type of the full view of the private extension. It
6864 -- must be A or a type derived from A.
6866 -- The rules concerning the discriminants of private type extensions are
6869 -- o If a private extension inherits known discriminants from the ancestor
6870 -- subtype, then the full view shall also inherit its discriminants from
6871 -- the ancestor subtype and the parent subtype of the full view shall be
6872 -- constrained if and only if the ancestor subtype is constrained.
6874 -- o If a partial view has unknown discriminants, then the full view may
6875 -- define a definite or an indefinite subtype, with or without
6878 -- o If a partial view has neither known nor unknown discriminants, then
6879 -- the full view shall define a definite subtype.
6881 -- o If the ancestor subtype of a private extension has constrained
6882 -- discriminants, then the parent subtype of the full view shall impose a
6883 -- statically matching constraint on those discriminants.
6885 -- This means that only the following forms of private extensions are
6888 -- type D is new A with private; <-- partial view
6889 -- type D is new P with null record; <-- full view
6891 -- If A has no discriminants than P has no discriminants, otherwise P must
6892 -- inherit A's discriminants.
6894 -- type D is new A (...) with private; <-- partial view
6895 -- type D is new P (:::) with null record; <-- full view
6897 -- P must inherit A's discriminants and (...) and (:::) must statically
6900 -- subtype A is R (...);
6901 -- type D is new A with private; <-- partial view
6902 -- type D is new P with null record; <-- full view
6904 -- P must have inherited R's discriminants and must be derived from A or
6905 -- any of its subtypes.
6907 -- type D (..) is new A with private; <-- partial view
6908 -- type D (..) is new P [(:::)] with null record; <-- full view
6910 -- No specific constraints on P's discriminants or constraint (:::).
6911 -- Note that A can be unconstrained, but the parent subtype P must either
6912 -- be constrained or (:::) must be present.
6914 -- type D (..) is new A [(...)] with private; <-- partial view
6915 -- type D (..) is new P [(:::)] with null record; <-- full view
6917 -- P's constraints on A's discriminants must statically match those
6918 -- imposed by (...).
6920 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
6922 -- The full view of a private extension is handled exactly as described
6923 -- above. The model chose for the private view of a private extension is
6924 -- the same for what concerns discriminants (i.e. they receive the same
6925 -- treatment as in the tagged case). However, the private view of the
6926 -- private extension always inherits the components of the parent base,
6927 -- without replacing any discriminant reference. Strictly speaking this is
6928 -- incorrect. However, Gigi never uses this view to generate code so this
6929 -- is a purely semantic issue. In theory, a set of transformations similar
6930 -- to those given in 5. and 6. above could be applied to private views of
6931 -- private extensions to have the same model of component inheritance as
6932 -- for non private extensions. However, this is not done because it would
6933 -- further complicate private type processing. Semantically speaking, this
6934 -- leaves us in an uncomfortable situation. As an example consider:
6937 -- type R (D : integer) is tagged record
6938 -- S : String (1 .. D);
6940 -- procedure P (X : R);
6941 -- type T is new R (1) with private;
6943 -- type T is new R (1) with null record;
6946 -- This is transformed into:
6949 -- type R (D : integer) is tagged record
6950 -- S : String (1 .. D);
6952 -- procedure P (X : R);
6953 -- type T is new R (1) with private;
6955 -- type BaseT is new R with null record;
6956 -- subtype T is BaseT (1);
6959 -- (strictly speaking the above is incorrect Ada)
6961 -- From the semantic standpoint the private view of private extension T
6962 -- should be flagged as constrained since one can clearly have
6966 -- in a unit withing Pack. However, when deriving subprograms for the
6967 -- private view of private extension T, T must be seen as unconstrained
6968 -- since T has discriminants (this is a constraint of the current
6969 -- subprogram derivation model). Thus, when processing the private view of
6970 -- a private extension such as T, we first mark T as unconstrained, we
6971 -- process it, we perform program derivation and just before returning from
6972 -- Build_Derived_Record_Type we mark T as constrained.
6974 -- ??? Are there are other uncomfortable cases that we will have to
6977 -- 10. RECORD_TYPE_WITH_PRIVATE complications
6979 -- Types that are derived from a visible record type and have a private
6980 -- extension present other peculiarities. They behave mostly like private
6981 -- types, but if they have primitive operations defined, these will not
6982 -- have the proper signatures for further inheritance, because other
6983 -- primitive operations will use the implicit base that we define for
6984 -- private derivations below. This affect subprogram inheritance (see
6985 -- Derive_Subprograms for details). We also derive the implicit base from
6986 -- the base type of the full view, so that the implicit base is a record
6987 -- type and not another private type, This avoids infinite loops.
6989 procedure Build_Derived_Record_Type
6991 Parent_Type : Entity_Id;
6992 Derived_Type : Entity_Id;
6993 Derive_Subps : Boolean := True)
6995 Discriminant_Specs : constant Boolean :=
6996 Present (Discriminant_Specifications (N));
6997 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
6998 Loc : constant Source_Ptr := Sloc (N);
6999 Private_Extension : constant Boolean :=
7000 Nkind (N) = N_Private_Extension_Declaration;
7001 Assoc_List : Elist_Id;
7002 Constraint_Present : Boolean;
7004 Discrim : Entity_Id;
7006 Inherit_Discrims : Boolean := False;
7007 Last_Discrim : Entity_Id;
7008 New_Base : Entity_Id;
7010 New_Discrs : Elist_Id;
7011 New_Indic : Node_Id;
7012 Parent_Base : Entity_Id;
7013 Save_Etype : Entity_Id;
7014 Save_Discr_Constr : Elist_Id;
7015 Save_Next_Entity : Entity_Id;
7018 Discs : Elist_Id := New_Elmt_List;
7019 -- An empty Discs list means that there were no constraints in the
7020 -- subtype indication or that there was an error processing it.
7023 if Ekind (Parent_Type) = E_Record_Type_With_Private
7024 and then Present (Full_View (Parent_Type))
7025 and then Has_Discriminants (Parent_Type)
7027 Parent_Base := Base_Type (Full_View (Parent_Type));
7029 Parent_Base := Base_Type (Parent_Type);
7032 -- Before we start the previously documented transformations, here is
7033 -- little fix for size and alignment of tagged types. Normally when we
7034 -- derive type D from type P, we copy the size and alignment of P as the
7035 -- default for D, and in the absence of explicit representation clauses
7036 -- for D, the size and alignment are indeed the same as the parent.
7038 -- But this is wrong for tagged types, since fields may be added, and
7039 -- the default size may need to be larger, and the default alignment may
7040 -- need to be larger.
7042 -- We therefore reset the size and alignment fields in the tagged case.
7043 -- Note that the size and alignment will in any case be at least as
7044 -- large as the parent type (since the derived type has a copy of the
7045 -- parent type in the _parent field)
7047 -- The type is also marked as being tagged here, which is needed when
7048 -- processing components with a self-referential anonymous access type
7049 -- in the call to Check_Anonymous_Access_Components below. Note that
7050 -- this flag is also set later on for completeness.
7053 Set_Is_Tagged_Type (Derived_Type);
7054 Init_Size_Align (Derived_Type);
7057 -- STEP 0a: figure out what kind of derived type declaration we have
7059 if Private_Extension then
7061 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
7064 Type_Def := Type_Definition (N);
7066 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7067 -- Parent_Base can be a private type or private extension. However,
7068 -- for tagged types with an extension the newly added fields are
7069 -- visible and hence the Derived_Type is always an E_Record_Type.
7070 -- (except that the parent may have its own private fields).
7071 -- For untagged types we preserve the Ekind of the Parent_Base.
7073 if Present (Record_Extension_Part (Type_Def)) then
7074 Set_Ekind (Derived_Type, E_Record_Type);
7076 -- Create internal access types for components with anonymous
7079 if Ada_Version >= Ada_2005 then
7080 Check_Anonymous_Access_Components
7081 (N, Derived_Type, Derived_Type,
7082 Component_List (Record_Extension_Part (Type_Def)));
7086 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7090 -- Indic can either be an N_Identifier if the subtype indication
7091 -- contains no constraint or an N_Subtype_Indication if the subtype
7092 -- indication has a constraint.
7094 Indic := Subtype_Indication (Type_Def);
7095 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
7097 -- Check that the type has visible discriminants. The type may be
7098 -- a private type with unknown discriminants whose full view has
7099 -- discriminants which are invisible.
7101 if Constraint_Present then
7102 if not Has_Discriminants (Parent_Base)
7104 (Has_Unknown_Discriminants (Parent_Base)
7105 and then Is_Private_Type (Parent_Base))
7108 ("invalid constraint: type has no discriminant",
7109 Constraint (Indic));
7111 Constraint_Present := False;
7112 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7114 elsif Is_Constrained (Parent_Type) then
7116 ("invalid constraint: parent type is already constrained",
7117 Constraint (Indic));
7119 Constraint_Present := False;
7120 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7124 -- STEP 0b: If needed, apply transformation given in point 5. above
7126 if not Private_Extension
7127 and then Has_Discriminants (Parent_Type)
7128 and then not Discriminant_Specs
7129 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
7131 -- First, we must analyze the constraint (see comment in point 5.)
7133 if Constraint_Present then
7134 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
7136 if Has_Discriminants (Derived_Type)
7137 and then Has_Private_Declaration (Derived_Type)
7138 and then Present (Discriminant_Constraint (Derived_Type))
7140 -- Verify that constraints of the full view statically match
7141 -- those given in the partial view.
7147 C1 := First_Elmt (New_Discrs);
7148 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
7149 while Present (C1) and then Present (C2) loop
7150 if Fully_Conformant_Expressions (Node (C1), Node (C2))
7152 (Is_OK_Static_Expression (Node (C1))
7154 Is_OK_Static_Expression (Node (C2))
7156 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
7162 "constraint not conformant to previous declaration",
7173 -- Insert and analyze the declaration for the unconstrained base type
7175 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
7178 Make_Full_Type_Declaration (Loc,
7179 Defining_Identifier => New_Base,
7181 Make_Derived_Type_Definition (Loc,
7182 Abstract_Present => Abstract_Present (Type_Def),
7183 Limited_Present => Limited_Present (Type_Def),
7184 Subtype_Indication =>
7185 New_Occurrence_Of (Parent_Base, Loc),
7186 Record_Extension_Part =>
7187 Relocate_Node (Record_Extension_Part (Type_Def)),
7188 Interface_List => Interface_List (Type_Def)));
7190 Set_Parent (New_Decl, Parent (N));
7191 Mark_Rewrite_Insertion (New_Decl);
7192 Insert_Before (N, New_Decl);
7194 -- In the extension case, make sure ancestor is frozen appropriately
7195 -- (see also non-discriminated case below).
7197 if Present (Record_Extension_Part (Type_Def))
7198 or else Is_Interface (Parent_Base)
7200 Freeze_Before (New_Decl, Parent_Type);
7203 -- Note that this call passes False for the Derive_Subps parameter
7204 -- because subprogram derivation is deferred until after creating
7205 -- the subtype (see below).
7208 (New_Decl, Parent_Base, New_Base,
7209 Is_Completion => True, Derive_Subps => False);
7211 -- ??? This needs re-examination to determine whether the
7212 -- above call can simply be replaced by a call to Analyze.
7214 Set_Analyzed (New_Decl);
7216 -- Insert and analyze the declaration for the constrained subtype
7218 if Constraint_Present then
7220 Make_Subtype_Indication (Loc,
7221 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
7222 Constraint => Relocate_Node (Constraint (Indic)));
7226 Constr_List : constant List_Id := New_List;
7231 C := First_Elmt (Discriminant_Constraint (Parent_Type));
7232 while Present (C) loop
7235 -- It is safe here to call New_Copy_Tree since
7236 -- Force_Evaluation was called on each constraint in
7237 -- Build_Discriminant_Constraints.
7239 Append (New_Copy_Tree (Expr), To => Constr_List);
7245 Make_Subtype_Indication (Loc,
7246 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
7248 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
7253 Make_Subtype_Declaration (Loc,
7254 Defining_Identifier => Derived_Type,
7255 Subtype_Indication => New_Indic));
7259 -- Derivation of subprograms must be delayed until the full subtype
7260 -- has been established, to ensure proper overriding of subprograms
7261 -- inherited by full types. If the derivations occurred as part of
7262 -- the call to Build_Derived_Type above, then the check for type
7263 -- conformance would fail because earlier primitive subprograms
7264 -- could still refer to the full type prior the change to the new
7265 -- subtype and hence would not match the new base type created here.
7266 -- Subprograms are not derived, however, when Derive_Subps is False
7267 -- (since otherwise there could be redundant derivations).
7269 if Derive_Subps then
7270 Derive_Subprograms (Parent_Type, Derived_Type);
7273 -- For tagged types the Discriminant_Constraint of the new base itype
7274 -- is inherited from the first subtype so that no subtype conformance
7275 -- problem arise when the first subtype overrides primitive
7276 -- operations inherited by the implicit base type.
7279 Set_Discriminant_Constraint
7280 (New_Base, Discriminant_Constraint (Derived_Type));
7286 -- If we get here Derived_Type will have no discriminants or it will be
7287 -- a discriminated unconstrained base type.
7289 -- STEP 1a: perform preliminary actions/checks for derived tagged types
7293 -- The parent type is frozen for non-private extensions (RM 13.14(7))
7294 -- The declaration of a specific descendant of an interface type
7295 -- freezes the interface type (RM 13.14).
7297 if not Private_Extension or else Is_Interface (Parent_Base) then
7298 Freeze_Before (N, Parent_Type);
7301 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
7302 -- cannot be declared at a deeper level than its parent type is
7303 -- removed. The check on derivation within a generic body is also
7304 -- relaxed, but there's a restriction that a derived tagged type
7305 -- cannot be declared in a generic body if it's derived directly
7306 -- or indirectly from a formal type of that generic.
7308 if Ada_Version >= Ada_2005 then
7309 if Present (Enclosing_Generic_Body (Derived_Type)) then
7311 Ancestor_Type : Entity_Id;
7314 -- Check to see if any ancestor of the derived type is a
7317 Ancestor_Type := Parent_Type;
7318 while not Is_Generic_Type (Ancestor_Type)
7319 and then Etype (Ancestor_Type) /= Ancestor_Type
7321 Ancestor_Type := Etype (Ancestor_Type);
7324 -- If the derived type does have a formal type as an
7325 -- ancestor, then it's an error if the derived type is
7326 -- declared within the body of the generic unit that
7327 -- declares the formal type in its generic formal part. It's
7328 -- sufficient to check whether the ancestor type is declared
7329 -- inside the same generic body as the derived type (such as
7330 -- within a nested generic spec), in which case the
7331 -- derivation is legal. If the formal type is declared
7332 -- outside of that generic body, then it's guaranteed that
7333 -- the derived type is declared within the generic body of
7334 -- the generic unit declaring the formal type.
7336 if Is_Generic_Type (Ancestor_Type)
7337 and then Enclosing_Generic_Body (Ancestor_Type) /=
7338 Enclosing_Generic_Body (Derived_Type)
7341 ("parent type of& must not be descendant of formal type"
7342 & " of an enclosing generic body",
7343 Indic, Derived_Type);
7348 elsif Type_Access_Level (Derived_Type) /=
7349 Type_Access_Level (Parent_Type)
7350 and then not Is_Generic_Type (Derived_Type)
7352 if Is_Controlled (Parent_Type) then
7354 ("controlled type must be declared at the library level",
7358 ("type extension at deeper accessibility level than parent",
7364 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
7368 and then GB /= Enclosing_Generic_Body (Parent_Base)
7371 ("parent type of& must not be outside generic body"
7373 Indic, Derived_Type);
7379 -- Ada 2005 (AI-251)
7381 if Ada_Version >= Ada_2005 and then Is_Tagged then
7383 -- "The declaration of a specific descendant of an interface type
7384 -- freezes the interface type" (RM 13.14).
7389 if Is_Non_Empty_List (Interface_List (Type_Def)) then
7390 Iface := First (Interface_List (Type_Def));
7391 while Present (Iface) loop
7392 Freeze_Before (N, Etype (Iface));
7399 -- STEP 1b : preliminary cleanup of the full view of private types
7401 -- If the type is already marked as having discriminants, then it's the
7402 -- completion of a private type or private extension and we need to
7403 -- retain the discriminants from the partial view if the current
7404 -- declaration has Discriminant_Specifications so that we can verify
7405 -- conformance. However, we must remove any existing components that
7406 -- were inherited from the parent (and attached in Copy_And_Swap)
7407 -- because the full type inherits all appropriate components anyway, and
7408 -- we do not want the partial view's components interfering.
7410 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
7411 Discrim := First_Discriminant (Derived_Type);
7413 Last_Discrim := Discrim;
7414 Next_Discriminant (Discrim);
7415 exit when No (Discrim);
7418 Set_Last_Entity (Derived_Type, Last_Discrim);
7420 -- In all other cases wipe out the list of inherited components (even
7421 -- inherited discriminants), it will be properly rebuilt here.
7424 Set_First_Entity (Derived_Type, Empty);
7425 Set_Last_Entity (Derived_Type, Empty);
7428 -- STEP 1c: Initialize some flags for the Derived_Type
7430 -- The following flags must be initialized here so that
7431 -- Process_Discriminants can check that discriminants of tagged types do
7432 -- not have a default initial value and that access discriminants are
7433 -- only specified for limited records. For completeness, these flags are
7434 -- also initialized along with all the other flags below.
7436 -- AI-419: Limitedness is not inherited from an interface parent, so to
7437 -- be limited in that case the type must be explicitly declared as
7438 -- limited. However, task and protected interfaces are always limited.
7440 if Limited_Present (Type_Def) then
7441 Set_Is_Limited_Record (Derived_Type);
7443 elsif Is_Limited_Record (Parent_Type)
7444 or else (Present (Full_View (Parent_Type))
7445 and then Is_Limited_Record (Full_View (Parent_Type)))
7447 if not Is_Interface (Parent_Type)
7448 or else Is_Synchronized_Interface (Parent_Type)
7449 or else Is_Protected_Interface (Parent_Type)
7450 or else Is_Task_Interface (Parent_Type)
7452 Set_Is_Limited_Record (Derived_Type);
7456 -- STEP 2a: process discriminants of derived type if any
7458 Push_Scope (Derived_Type);
7460 if Discriminant_Specs then
7461 Set_Has_Unknown_Discriminants (Derived_Type, False);
7463 -- The following call initializes fields Has_Discriminants and
7464 -- Discriminant_Constraint, unless we are processing the completion
7465 -- of a private type declaration.
7467 Check_Or_Process_Discriminants (N, Derived_Type);
7469 -- For untagged types, the constraint on the Parent_Type must be
7470 -- present and is used to rename the discriminants.
7472 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
7473 Error_Msg_N ("untagged parent must have discriminants", Indic);
7475 elsif not Is_Tagged and then not Constraint_Present then
7477 ("discriminant constraint needed for derived untagged records",
7480 -- Otherwise the parent subtype must be constrained unless we have a
7481 -- private extension.
7483 elsif not Constraint_Present
7484 and then not Private_Extension
7485 and then not Is_Constrained (Parent_Type)
7488 ("unconstrained type not allowed in this context", Indic);
7490 elsif Constraint_Present then
7491 -- The following call sets the field Corresponding_Discriminant
7492 -- for the discriminants in the Derived_Type.
7494 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
7496 -- For untagged types all new discriminants must rename
7497 -- discriminants in the parent. For private extensions new
7498 -- discriminants cannot rename old ones (implied by [7.3(13)]).
7500 Discrim := First_Discriminant (Derived_Type);
7501 while Present (Discrim) loop
7503 and then No (Corresponding_Discriminant (Discrim))
7506 ("new discriminants must constrain old ones", Discrim);
7508 elsif Private_Extension
7509 and then Present (Corresponding_Discriminant (Discrim))
7512 ("only static constraints allowed for parent"
7513 & " discriminants in the partial view", Indic);
7517 -- If a new discriminant is used in the constraint, then its
7518 -- subtype must be statically compatible with the parent
7519 -- discriminant's subtype (3.7(15)).
7521 if Present (Corresponding_Discriminant (Discrim))
7523 not Subtypes_Statically_Compatible
7525 Etype (Corresponding_Discriminant (Discrim)))
7528 ("subtype must be compatible with parent discriminant",
7532 Next_Discriminant (Discrim);
7535 -- Check whether the constraints of the full view statically
7536 -- match those imposed by the parent subtype [7.3(13)].
7538 if Present (Stored_Constraint (Derived_Type)) then
7543 C1 := First_Elmt (Discs);
7544 C2 := First_Elmt (Stored_Constraint (Derived_Type));
7545 while Present (C1) and then Present (C2) loop
7547 Fully_Conformant_Expressions (Node (C1), Node (C2))
7550 ("not conformant with previous declaration",
7561 -- STEP 2b: No new discriminants, inherit discriminants if any
7564 if Private_Extension then
7565 Set_Has_Unknown_Discriminants
7567 Has_Unknown_Discriminants (Parent_Type)
7568 or else Unknown_Discriminants_Present (N));
7570 -- The partial view of the parent may have unknown discriminants,
7571 -- but if the full view has discriminants and the parent type is
7572 -- in scope they must be inherited.
7574 elsif Has_Unknown_Discriminants (Parent_Type)
7576 (not Has_Discriminants (Parent_Type)
7577 or else not In_Open_Scopes (Scope (Parent_Type)))
7579 Set_Has_Unknown_Discriminants (Derived_Type);
7582 if not Has_Unknown_Discriminants (Derived_Type)
7583 and then not Has_Unknown_Discriminants (Parent_Base)
7584 and then Has_Discriminants (Parent_Type)
7586 Inherit_Discrims := True;
7587 Set_Has_Discriminants
7588 (Derived_Type, True);
7589 Set_Discriminant_Constraint
7590 (Derived_Type, Discriminant_Constraint (Parent_Base));
7593 -- The following test is true for private types (remember
7594 -- transformation 5. is not applied to those) and in an error
7597 if Constraint_Present then
7598 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
7601 -- For now mark a new derived type as constrained only if it has no
7602 -- discriminants. At the end of Build_Derived_Record_Type we properly
7603 -- set this flag in the case of private extensions. See comments in
7604 -- point 9. just before body of Build_Derived_Record_Type.
7608 not (Inherit_Discrims
7609 or else Has_Unknown_Discriminants (Derived_Type)));
7612 -- STEP 3: initialize fields of derived type
7614 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
7615 Set_Stored_Constraint (Derived_Type, No_Elist);
7617 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
7618 -- but cannot be interfaces
7620 if not Private_Extension
7621 and then Ekind (Derived_Type) /= E_Private_Type
7622 and then Ekind (Derived_Type) /= E_Limited_Private_Type
7624 if Interface_Present (Type_Def) then
7625 Analyze_Interface_Declaration (Derived_Type, Type_Def);
7628 Set_Interfaces (Derived_Type, No_Elist);
7631 -- Fields inherited from the Parent_Type
7634 (Derived_Type, Einfo.Discard_Names (Parent_Type));
7635 Set_Has_Specified_Layout
7636 (Derived_Type, Has_Specified_Layout (Parent_Type));
7637 Set_Is_Limited_Composite
7638 (Derived_Type, Is_Limited_Composite (Parent_Type));
7639 Set_Is_Private_Composite
7640 (Derived_Type, Is_Private_Composite (Parent_Type));
7642 -- Fields inherited from the Parent_Base
7644 Set_Has_Controlled_Component
7645 (Derived_Type, Has_Controlled_Component (Parent_Base));
7646 Set_Has_Non_Standard_Rep
7647 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7648 Set_Has_Primitive_Operations
7649 (Derived_Type, Has_Primitive_Operations (Parent_Base));
7651 -- Fields inherited from the Parent_Base in the non-private case
7653 if Ekind (Derived_Type) = E_Record_Type then
7654 Set_Has_Complex_Representation
7655 (Derived_Type, Has_Complex_Representation (Parent_Base));
7658 -- Fields inherited from the Parent_Base for record types
7660 if Is_Record_Type (Derived_Type) then
7662 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7663 -- Parent_Base can be a private type or private extension.
7665 if Present (Full_View (Parent_Base)) then
7666 Set_OK_To_Reorder_Components
7668 OK_To_Reorder_Components (Full_View (Parent_Base)));
7669 Set_Reverse_Bit_Order
7670 (Derived_Type, Reverse_Bit_Order (Full_View (Parent_Base)));
7672 Set_OK_To_Reorder_Components
7673 (Derived_Type, OK_To_Reorder_Components (Parent_Base));
7674 Set_Reverse_Bit_Order
7675 (Derived_Type, Reverse_Bit_Order (Parent_Base));
7679 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7681 if not Is_Controlled (Parent_Type) then
7682 Set_Finalize_Storage_Only
7683 (Derived_Type, Finalize_Storage_Only (Parent_Type));
7686 -- Set fields for private derived types
7688 if Is_Private_Type (Derived_Type) then
7689 Set_Depends_On_Private (Derived_Type, True);
7690 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7692 -- Inherit fields from non private record types. If this is the
7693 -- completion of a derivation from a private type, the parent itself
7694 -- is private, and the attributes come from its full view, which must
7698 if Is_Private_Type (Parent_Base)
7699 and then not Is_Record_Type (Parent_Base)
7701 Set_Component_Alignment
7702 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
7704 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
7706 Set_Component_Alignment
7707 (Derived_Type, Component_Alignment (Parent_Base));
7709 (Derived_Type, C_Pass_By_Copy (Parent_Base));
7713 -- Set fields for tagged types
7716 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
7718 -- All tagged types defined in Ada.Finalization are controlled
7720 if Chars (Scope (Derived_Type)) = Name_Finalization
7721 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
7722 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
7724 Set_Is_Controlled (Derived_Type);
7726 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
7729 -- Minor optimization: there is no need to generate the class-wide
7730 -- entity associated with an underlying record view.
7732 if not Is_Underlying_Record_View (Derived_Type) then
7733 Make_Class_Wide_Type (Derived_Type);
7736 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
7738 if Has_Discriminants (Derived_Type)
7739 and then Constraint_Present
7741 Set_Stored_Constraint
7742 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
7745 if Ada_Version >= Ada_2005 then
7747 Ifaces_List : Elist_Id;
7750 -- Checks rules 3.9.4 (13/2 and 14/2)
7752 if Comes_From_Source (Derived_Type)
7753 and then not Is_Private_Type (Derived_Type)
7754 and then Is_Interface (Parent_Type)
7755 and then not Is_Interface (Derived_Type)
7757 if Is_Task_Interface (Parent_Type) then
7759 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
7762 elsif Is_Protected_Interface (Parent_Type) then
7764 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
7769 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
7771 Check_Interfaces (N, Type_Def);
7773 -- Ada 2005 (AI-251): Collect the list of progenitors that are
7774 -- not already in the parents.
7778 Ifaces_List => Ifaces_List,
7779 Exclude_Parents => True);
7781 Set_Interfaces (Derived_Type, Ifaces_List);
7783 -- If the derived type is the anonymous type created for
7784 -- a declaration whose parent has a constraint, propagate
7785 -- the interface list to the source type. This must be done
7786 -- prior to the completion of the analysis of the source type
7787 -- because the components in the extension may contain current
7788 -- instances whose legality depends on some ancestor.
7790 if Is_Itype (Derived_Type) then
7792 Def : constant Node_Id :=
7793 Associated_Node_For_Itype (Derived_Type);
7796 and then Nkind (Def) = N_Full_Type_Declaration
7799 (Defining_Identifier (Def), Ifaces_List);
7807 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
7808 Set_Has_Non_Standard_Rep
7809 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7812 -- STEP 4: Inherit components from the parent base and constrain them.
7813 -- Apply the second transformation described in point 6. above.
7815 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
7816 or else not Has_Discriminants (Parent_Type)
7817 or else not Is_Constrained (Parent_Type)
7821 Constrs := Discriminant_Constraint (Parent_Type);
7826 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
7828 -- STEP 5a: Copy the parent record declaration for untagged types
7830 if not Is_Tagged then
7832 -- Discriminant_Constraint (Derived_Type) has been properly
7833 -- constructed. Save it and temporarily set it to Empty because we
7834 -- do not want the call to New_Copy_Tree below to mess this list.
7836 if Has_Discriminants (Derived_Type) then
7837 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
7838 Set_Discriminant_Constraint (Derived_Type, No_Elist);
7840 Save_Discr_Constr := No_Elist;
7843 -- Save the Etype field of Derived_Type. It is correctly set now,
7844 -- but the call to New_Copy tree may remap it to point to itself,
7845 -- which is not what we want. Ditto for the Next_Entity field.
7847 Save_Etype := Etype (Derived_Type);
7848 Save_Next_Entity := Next_Entity (Derived_Type);
7850 -- Assoc_List maps all stored discriminants in the Parent_Base to
7851 -- stored discriminants in the Derived_Type. It is fundamental that
7852 -- no types or itypes with discriminants other than the stored
7853 -- discriminants appear in the entities declared inside
7854 -- Derived_Type, since the back end cannot deal with it.
7858 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
7860 -- Restore the fields saved prior to the New_Copy_Tree call
7861 -- and compute the stored constraint.
7863 Set_Etype (Derived_Type, Save_Etype);
7864 Set_Next_Entity (Derived_Type, Save_Next_Entity);
7866 if Has_Discriminants (Derived_Type) then
7867 Set_Discriminant_Constraint
7868 (Derived_Type, Save_Discr_Constr);
7869 Set_Stored_Constraint
7870 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
7871 Replace_Components (Derived_Type, New_Decl);
7874 -- Insert the new derived type declaration
7876 Rewrite (N, New_Decl);
7878 -- STEP 5b: Complete the processing for record extensions in generics
7880 -- There is no completion for record extensions declared in the
7881 -- parameter part of a generic, so we need to complete processing for
7882 -- these generic record extensions here. The Record_Type_Definition call
7883 -- will change the Ekind of the components from E_Void to E_Component.
7885 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
7886 Record_Type_Definition (Empty, Derived_Type);
7888 -- STEP 5c: Process the record extension for non private tagged types
7890 elsif not Private_Extension then
7892 -- Add the _parent field in the derived type
7894 Expand_Record_Extension (Derived_Type, Type_Def);
7896 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
7897 -- implemented interfaces if we are in expansion mode
7900 and then Has_Interfaces (Derived_Type)
7902 Add_Interface_Tag_Components (N, Derived_Type);
7905 -- Analyze the record extension
7907 Record_Type_Definition
7908 (Record_Extension_Part (Type_Def), Derived_Type);
7913 -- Nothing else to do if there is an error in the derivation.
7914 -- An unusual case: the full view may be derived from a type in an
7915 -- instance, when the partial view was used illegally as an actual
7916 -- in that instance, leading to a circular definition.
7918 if Etype (Derived_Type) = Any_Type
7919 or else Etype (Parent_Type) = Derived_Type
7924 -- Set delayed freeze and then derive subprograms, we need to do
7925 -- this in this order so that derived subprograms inherit the
7926 -- derived freeze if necessary.
7928 Set_Has_Delayed_Freeze (Derived_Type);
7930 if Derive_Subps then
7931 Derive_Subprograms (Parent_Type, Derived_Type);
7934 -- If we have a private extension which defines a constrained derived
7935 -- type mark as constrained here after we have derived subprograms. See
7936 -- comment on point 9. just above the body of Build_Derived_Record_Type.
7938 if Private_Extension and then Inherit_Discrims then
7939 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
7940 Set_Is_Constrained (Derived_Type, True);
7941 Set_Discriminant_Constraint (Derived_Type, Discs);
7943 elsif Is_Constrained (Parent_Type) then
7945 (Derived_Type, True);
7946 Set_Discriminant_Constraint
7947 (Derived_Type, Discriminant_Constraint (Parent_Type));
7951 -- Update the class-wide type, which shares the now-completed entity
7952 -- list with its specific type. In case of underlying record views,
7953 -- we do not generate the corresponding class wide entity.
7956 and then not Is_Underlying_Record_View (Derived_Type)
7959 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
7961 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
7964 -- Update the scope of anonymous access types of discriminants and other
7965 -- components, to prevent scope anomalies in gigi, when the derivation
7966 -- appears in a scope nested within that of the parent.
7972 D := First_Entity (Derived_Type);
7973 while Present (D) loop
7974 if Ekind_In (D, E_Discriminant, E_Component) then
7975 if Is_Itype (Etype (D))
7976 and then Ekind (Etype (D)) = E_Anonymous_Access_Type
7978 Set_Scope (Etype (D), Current_Scope);
7985 end Build_Derived_Record_Type;
7987 ------------------------
7988 -- Build_Derived_Type --
7989 ------------------------
7991 procedure Build_Derived_Type
7993 Parent_Type : Entity_Id;
7994 Derived_Type : Entity_Id;
7995 Is_Completion : Boolean;
7996 Derive_Subps : Boolean := True)
7998 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
8001 -- Set common attributes
8003 Set_Scope (Derived_Type, Current_Scope);
8005 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8006 Set_Etype (Derived_Type, Parent_Base);
8007 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
8009 Set_Size_Info (Derived_Type, Parent_Type);
8010 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
8011 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
8012 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
8014 -- If the parent type is a private subtype, the convention on the base
8015 -- type may be set in the private part, and not propagated to the
8016 -- subtype until later, so we obtain the convention from the base type.
8018 Set_Convention (Derived_Type, Convention (Parent_Base));
8020 -- Propagate invariant information. The new type has invariants if
8021 -- they are inherited from the parent type, and these invariants can
8022 -- be further inherited, so both flags are set.
8024 if Has_Inheritable_Invariants (Parent_Type) then
8025 Set_Has_Inheritable_Invariants (Derived_Type);
8026 Set_Has_Invariants (Derived_Type);
8029 -- We similarly inherit predicates
8031 if Has_Predicates (Parent_Type) then
8032 Set_Has_Predicates (Derived_Type);
8035 -- The derived type inherits the representation clauses of the parent.
8036 -- However, for a private type that is completed by a derivation, there
8037 -- may be operation attributes that have been specified already (stream
8038 -- attributes and External_Tag) and those must be provided. Finally,
8039 -- if the partial view is a private extension, the representation items
8040 -- of the parent have been inherited already, and should not be chained
8041 -- twice to the derived type.
8043 if Is_Tagged_Type (Parent_Type)
8044 and then Present (First_Rep_Item (Derived_Type))
8046 -- The existing items are either operational items or items inherited
8047 -- from a private extension declaration.
8051 -- Used to iterate over representation items of the derived type
8054 -- Last representation item of the (non-empty) representation
8055 -- item list of the derived type.
8057 Found : Boolean := False;
8060 Rep := First_Rep_Item (Derived_Type);
8062 while Present (Rep) loop
8063 if Rep = First_Rep_Item (Parent_Type) then
8068 Rep := Next_Rep_Item (Rep);
8070 if Present (Rep) then
8076 -- Here if we either encountered the parent type's first rep
8077 -- item on the derived type's rep item list (in which case
8078 -- Found is True, and we have nothing else to do), or if we
8079 -- reached the last rep item of the derived type, which is
8080 -- Last_Rep, in which case we further chain the parent type's
8081 -- rep items to those of the derived type.
8084 Set_Next_Rep_Item (Last_Rep, First_Rep_Item (Parent_Type));
8089 Set_First_Rep_Item (Derived_Type, First_Rep_Item (Parent_Type));
8092 case Ekind (Parent_Type) is
8093 when Numeric_Kind =>
8094 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
8097 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
8101 | Class_Wide_Kind =>
8102 Build_Derived_Record_Type
8103 (N, Parent_Type, Derived_Type, Derive_Subps);
8106 when Enumeration_Kind =>
8107 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
8110 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
8112 when Incomplete_Or_Private_Kind =>
8113 Build_Derived_Private_Type
8114 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
8116 -- For discriminated types, the derivation includes deriving
8117 -- primitive operations. For others it is done below.
8119 if Is_Tagged_Type (Parent_Type)
8120 or else Has_Discriminants (Parent_Type)
8121 or else (Present (Full_View (Parent_Type))
8122 and then Has_Discriminants (Full_View (Parent_Type)))
8127 when Concurrent_Kind =>
8128 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
8131 raise Program_Error;
8134 if Etype (Derived_Type) = Any_Type then
8138 -- Set delayed freeze and then derive subprograms, we need to do this
8139 -- in this order so that derived subprograms inherit the derived freeze
8142 Set_Has_Delayed_Freeze (Derived_Type);
8143 if Derive_Subps then
8144 Derive_Subprograms (Parent_Type, Derived_Type);
8147 Set_Has_Primitive_Operations
8148 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
8149 end Build_Derived_Type;
8151 -----------------------
8152 -- Build_Discriminal --
8153 -----------------------
8155 procedure Build_Discriminal (Discrim : Entity_Id) is
8156 D_Minal : Entity_Id;
8157 CR_Disc : Entity_Id;
8160 -- A discriminal has the same name as the discriminant
8162 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8164 Set_Ekind (D_Minal, E_In_Parameter);
8165 Set_Mechanism (D_Minal, Default_Mechanism);
8166 Set_Etype (D_Minal, Etype (Discrim));
8167 Set_Scope (D_Minal, Current_Scope);
8169 Set_Discriminal (Discrim, D_Minal);
8170 Set_Discriminal_Link (D_Minal, Discrim);
8172 -- For task types, build at once the discriminants of the corresponding
8173 -- record, which are needed if discriminants are used in entry defaults
8174 -- and in family bounds.
8176 if Is_Concurrent_Type (Current_Scope)
8177 or else Is_Limited_Type (Current_Scope)
8179 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8181 Set_Ekind (CR_Disc, E_In_Parameter);
8182 Set_Mechanism (CR_Disc, Default_Mechanism);
8183 Set_Etype (CR_Disc, Etype (Discrim));
8184 Set_Scope (CR_Disc, Current_Scope);
8185 Set_Discriminal_Link (CR_Disc, Discrim);
8186 Set_CR_Discriminant (Discrim, CR_Disc);
8188 end Build_Discriminal;
8190 ------------------------------------
8191 -- Build_Discriminant_Constraints --
8192 ------------------------------------
8194 function Build_Discriminant_Constraints
8197 Derived_Def : Boolean := False) return Elist_Id
8199 C : constant Node_Id := Constraint (Def);
8200 Nb_Discr : constant Nat := Number_Discriminants (T);
8202 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
8203 -- Saves the expression corresponding to a given discriminant in T
8205 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
8206 -- Return the Position number within array Discr_Expr of a discriminant
8207 -- D within the discriminant list of the discriminated type T.
8213 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
8217 Disc := First_Discriminant (T);
8218 for J in Discr_Expr'Range loop
8223 Next_Discriminant (Disc);
8226 -- Note: Since this function is called on discriminants that are
8227 -- known to belong to the discriminated type, falling through the
8228 -- loop with no match signals an internal compiler error.
8230 raise Program_Error;
8233 -- Declarations local to Build_Discriminant_Constraints
8237 Elist : constant Elist_Id := New_Elmt_List;
8245 Discrim_Present : Boolean := False;
8247 -- Start of processing for Build_Discriminant_Constraints
8250 -- The following loop will process positional associations only.
8251 -- For a positional association, the (single) discriminant is
8252 -- implicitly specified by position, in textual order (RM 3.7.2).
8254 Discr := First_Discriminant (T);
8255 Constr := First (Constraints (C));
8256 for D in Discr_Expr'Range loop
8257 exit when Nkind (Constr) = N_Discriminant_Association;
8260 Error_Msg_N ("too few discriminants given in constraint", C);
8261 return New_Elmt_List;
8263 elsif Nkind (Constr) = N_Range
8264 or else (Nkind (Constr) = N_Attribute_Reference
8266 Attribute_Name (Constr) = Name_Range)
8269 ("a range is not a valid discriminant constraint", Constr);
8270 Discr_Expr (D) := Error;
8273 Analyze_And_Resolve (Constr, Base_Type (Etype (Discr)));
8274 Discr_Expr (D) := Constr;
8277 Next_Discriminant (Discr);
8281 if No (Discr) and then Present (Constr) then
8282 Error_Msg_N ("too many discriminants given in constraint", Constr);
8283 return New_Elmt_List;
8286 -- Named associations can be given in any order, but if both positional
8287 -- and named associations are used in the same discriminant constraint,
8288 -- then positional associations must occur first, at their normal
8289 -- position. Hence once a named association is used, the rest of the
8290 -- discriminant constraint must use only named associations.
8292 while Present (Constr) loop
8294 -- Positional association forbidden after a named association
8296 if Nkind (Constr) /= N_Discriminant_Association then
8297 Error_Msg_N ("positional association follows named one", Constr);
8298 return New_Elmt_List;
8300 -- Otherwise it is a named association
8303 -- E records the type of the discriminants in the named
8304 -- association. All the discriminants specified in the same name
8305 -- association must have the same type.
8309 -- Search the list of discriminants in T to see if the simple name
8310 -- given in the constraint matches any of them.
8312 Id := First (Selector_Names (Constr));
8313 while Present (Id) loop
8316 -- If Original_Discriminant is present, we are processing a
8317 -- generic instantiation and this is an instance node. We need
8318 -- to find the name of the corresponding discriminant in the
8319 -- actual record type T and not the name of the discriminant in
8320 -- the generic formal. Example:
8323 -- type G (D : int) is private;
8325 -- subtype W is G (D => 1);
8327 -- type Rec (X : int) is record ... end record;
8328 -- package Q is new P (G => Rec);
8330 -- At the point of the instantiation, formal type G is Rec
8331 -- and therefore when reanalyzing "subtype W is G (D => 1);"
8332 -- which really looks like "subtype W is Rec (D => 1);" at
8333 -- the point of instantiation, we want to find the discriminant
8334 -- that corresponds to D in Rec, i.e. X.
8336 if Present (Original_Discriminant (Id))
8337 and then In_Instance
8339 Discr := Find_Corresponding_Discriminant (Id, T);
8343 Discr := First_Discriminant (T);
8344 while Present (Discr) loop
8345 if Chars (Discr) = Chars (Id) then
8350 Next_Discriminant (Discr);
8354 Error_Msg_N ("& does not match any discriminant", Id);
8355 return New_Elmt_List;
8357 -- The following is only useful for the benefit of generic
8358 -- instances but it does not interfere with other
8359 -- processing for the non-generic case so we do it in all
8360 -- cases (for generics this statement is executed when
8361 -- processing the generic definition, see comment at the
8362 -- beginning of this if statement).
8365 Set_Original_Discriminant (Id, Discr);
8369 Position := Pos_Of_Discr (T, Discr);
8371 if Present (Discr_Expr (Position)) then
8372 Error_Msg_N ("duplicate constraint for discriminant&", Id);
8375 -- Each discriminant specified in the same named association
8376 -- must be associated with a separate copy of the
8377 -- corresponding expression.
8379 if Present (Next (Id)) then
8380 Expr := New_Copy_Tree (Expression (Constr));
8381 Set_Parent (Expr, Parent (Expression (Constr)));
8383 Expr := Expression (Constr);
8386 Discr_Expr (Position) := Expr;
8387 Analyze_And_Resolve (Expr, Base_Type (Etype (Discr)));
8390 -- A discriminant association with more than one discriminant
8391 -- name is only allowed if the named discriminants are all of
8392 -- the same type (RM 3.7.1(8)).
8395 E := Base_Type (Etype (Discr));
8397 elsif Base_Type (Etype (Discr)) /= E then
8399 ("all discriminants in an association " &
8400 "must have the same type", Id);
8410 -- A discriminant constraint must provide exactly one value for each
8411 -- discriminant of the type (RM 3.7.1(8)).
8413 for J in Discr_Expr'Range loop
8414 if No (Discr_Expr (J)) then
8415 Error_Msg_N ("too few discriminants given in constraint", C);
8416 return New_Elmt_List;
8420 -- Determine if there are discriminant expressions in the constraint
8422 for J in Discr_Expr'Range loop
8423 if Denotes_Discriminant
8424 (Discr_Expr (J), Check_Concurrent => True)
8426 Discrim_Present := True;
8430 -- Build an element list consisting of the expressions given in the
8431 -- discriminant constraint and apply the appropriate checks. The list
8432 -- is constructed after resolving any named discriminant associations
8433 -- and therefore the expressions appear in the textual order of the
8436 Discr := First_Discriminant (T);
8437 for J in Discr_Expr'Range loop
8438 if Discr_Expr (J) /= Error then
8439 Append_Elmt (Discr_Expr (J), Elist);
8441 -- If any of the discriminant constraints is given by a
8442 -- discriminant and we are in a derived type declaration we
8443 -- have a discriminant renaming. Establish link between new
8444 -- and old discriminant.
8446 if Denotes_Discriminant (Discr_Expr (J)) then
8448 Set_Corresponding_Discriminant
8449 (Entity (Discr_Expr (J)), Discr);
8452 -- Force the evaluation of non-discriminant expressions.
8453 -- If we have found a discriminant in the constraint 3.4(26)
8454 -- and 3.8(18) demand that no range checks are performed are
8455 -- after evaluation. If the constraint is for a component
8456 -- definition that has a per-object constraint, expressions are
8457 -- evaluated but not checked either. In all other cases perform
8461 if Discrim_Present then
8464 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
8466 Has_Per_Object_Constraint
8467 (Defining_Identifier (Parent (Parent (Def))))
8471 elsif Is_Access_Type (Etype (Discr)) then
8472 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
8475 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
8478 Force_Evaluation (Discr_Expr (J));
8481 -- Check that the designated type of an access discriminant's
8482 -- expression is not a class-wide type unless the discriminant's
8483 -- designated type is also class-wide.
8485 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
8486 and then not Is_Class_Wide_Type
8487 (Designated_Type (Etype (Discr)))
8488 and then Etype (Discr_Expr (J)) /= Any_Type
8489 and then Is_Class_Wide_Type
8490 (Designated_Type (Etype (Discr_Expr (J))))
8492 Wrong_Type (Discr_Expr (J), Etype (Discr));
8494 elsif Is_Access_Type (Etype (Discr))
8495 and then not Is_Access_Constant (Etype (Discr))
8496 and then Is_Access_Type (Etype (Discr_Expr (J)))
8497 and then Is_Access_Constant (Etype (Discr_Expr (J)))
8500 ("constraint for discriminant& must be access to variable",
8505 Next_Discriminant (Discr);
8509 end Build_Discriminant_Constraints;
8511 ---------------------------------
8512 -- Build_Discriminated_Subtype --
8513 ---------------------------------
8515 procedure Build_Discriminated_Subtype
8519 Related_Nod : Node_Id;
8520 For_Access : Boolean := False)
8522 Has_Discrs : constant Boolean := Has_Discriminants (T);
8523 Constrained : constant Boolean :=
8525 and then not Is_Empty_Elmt_List (Elist)
8526 and then not Is_Class_Wide_Type (T))
8527 or else Is_Constrained (T);
8530 if Ekind (T) = E_Record_Type then
8532 Set_Ekind (Def_Id, E_Private_Subtype);
8533 Set_Is_For_Access_Subtype (Def_Id, True);
8535 Set_Ekind (Def_Id, E_Record_Subtype);
8538 -- Inherit preelaboration flag from base, for types for which it
8539 -- may have been set: records, private types, protected types.
8541 Set_Known_To_Have_Preelab_Init
8542 (Def_Id, Known_To_Have_Preelab_Init (T));
8544 elsif Ekind (T) = E_Task_Type then
8545 Set_Ekind (Def_Id, E_Task_Subtype);
8547 elsif Ekind (T) = E_Protected_Type then
8548 Set_Ekind (Def_Id, E_Protected_Subtype);
8549 Set_Known_To_Have_Preelab_Init
8550 (Def_Id, Known_To_Have_Preelab_Init (T));
8552 elsif Is_Private_Type (T) then
8553 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
8554 Set_Known_To_Have_Preelab_Init
8555 (Def_Id, Known_To_Have_Preelab_Init (T));
8557 elsif Is_Class_Wide_Type (T) then
8558 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
8561 -- Incomplete type. Attach subtype to list of dependents, to be
8562 -- completed with full view of parent type, unless is it the
8563 -- designated subtype of a record component within an init_proc.
8564 -- This last case arises for a component of an access type whose
8565 -- designated type is incomplete (e.g. a Taft Amendment type).
8566 -- The designated subtype is within an inner scope, and needs no
8567 -- elaboration, because only the access type is needed in the
8568 -- initialization procedure.
8570 Set_Ekind (Def_Id, Ekind (T));
8572 if For_Access and then Within_Init_Proc then
8575 Append_Elmt (Def_Id, Private_Dependents (T));
8579 Set_Etype (Def_Id, T);
8580 Init_Size_Align (Def_Id);
8581 Set_Has_Discriminants (Def_Id, Has_Discrs);
8582 Set_Is_Constrained (Def_Id, Constrained);
8584 Set_First_Entity (Def_Id, First_Entity (T));
8585 Set_Last_Entity (Def_Id, Last_Entity (T));
8587 -- If the subtype is the completion of a private declaration, there may
8588 -- have been representation clauses for the partial view, and they must
8589 -- be preserved. Build_Derived_Type chains the inherited clauses with
8590 -- the ones appearing on the extension. If this comes from a subtype
8591 -- declaration, all clauses are inherited.
8593 if No (First_Rep_Item (Def_Id)) then
8594 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
8597 if Is_Tagged_Type (T) then
8598 Set_Is_Tagged_Type (Def_Id);
8599 Make_Class_Wide_Type (Def_Id);
8602 Set_Stored_Constraint (Def_Id, No_Elist);
8605 Set_Discriminant_Constraint (Def_Id, Elist);
8606 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
8609 if Is_Tagged_Type (T) then
8611 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
8612 -- concurrent record type (which has the list of primitive
8615 if Ada_Version >= Ada_2005
8616 and then Is_Concurrent_Type (T)
8618 Set_Corresponding_Record_Type (Def_Id,
8619 Corresponding_Record_Type (T));
8621 Set_Direct_Primitive_Operations (Def_Id,
8622 Direct_Primitive_Operations (T));
8625 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
8628 -- Subtypes introduced by component declarations do not need to be
8629 -- marked as delayed, and do not get freeze nodes, because the semantics
8630 -- verifies that the parents of the subtypes are frozen before the
8631 -- enclosing record is frozen.
8633 if not Is_Type (Scope (Def_Id)) then
8634 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
8636 if Is_Private_Type (T)
8637 and then Present (Full_View (T))
8639 Conditional_Delay (Def_Id, Full_View (T));
8641 Conditional_Delay (Def_Id, T);
8645 if Is_Record_Type (T) then
8646 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
8649 and then not Is_Empty_Elmt_List (Elist)
8650 and then not For_Access
8652 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
8653 elsif not For_Access then
8654 Set_Cloned_Subtype (Def_Id, T);
8657 end Build_Discriminated_Subtype;
8659 ---------------------------
8660 -- Build_Itype_Reference --
8661 ---------------------------
8663 procedure Build_Itype_Reference
8667 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
8670 -- Itype references are only created for use by the back-end
8672 if Inside_A_Generic then
8675 Set_Itype (IR, Ityp);
8676 Insert_After (Nod, IR);
8678 end Build_Itype_Reference;
8680 ------------------------
8681 -- Build_Scalar_Bound --
8682 ------------------------
8684 function Build_Scalar_Bound
8687 Der_T : Entity_Id) return Node_Id
8689 New_Bound : Entity_Id;
8692 -- Note: not clear why this is needed, how can the original bound
8693 -- be unanalyzed at this point? and if it is, what business do we
8694 -- have messing around with it? and why is the base type of the
8695 -- parent type the right type for the resolution. It probably is
8696 -- not! It is OK for the new bound we are creating, but not for
8697 -- the old one??? Still if it never happens, no problem!
8699 Analyze_And_Resolve (Bound, Base_Type (Par_T));
8701 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
8702 New_Bound := New_Copy (Bound);
8703 Set_Etype (New_Bound, Der_T);
8704 Set_Analyzed (New_Bound);
8706 elsif Is_Entity_Name (Bound) then
8707 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
8709 -- The following is almost certainly wrong. What business do we have
8710 -- relocating a node (Bound) that is presumably still attached to
8711 -- the tree elsewhere???
8714 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
8717 Set_Etype (New_Bound, Der_T);
8719 end Build_Scalar_Bound;
8721 --------------------------------
8722 -- Build_Underlying_Full_View --
8723 --------------------------------
8725 procedure Build_Underlying_Full_View
8730 Loc : constant Source_Ptr := Sloc (N);
8731 Subt : constant Entity_Id :=
8732 Make_Defining_Identifier
8733 (Loc, New_External_Name (Chars (Typ), 'S'));
8740 procedure Set_Discriminant_Name (Id : Node_Id);
8741 -- If the derived type has discriminants, they may rename discriminants
8742 -- of the parent. When building the full view of the parent, we need to
8743 -- recover the names of the original discriminants if the constraint is
8744 -- given by named associations.
8746 ---------------------------
8747 -- Set_Discriminant_Name --
8748 ---------------------------
8750 procedure Set_Discriminant_Name (Id : Node_Id) is
8754 Set_Original_Discriminant (Id, Empty);
8756 if Has_Discriminants (Typ) then
8757 Disc := First_Discriminant (Typ);
8758 while Present (Disc) loop
8759 if Chars (Disc) = Chars (Id)
8760 and then Present (Corresponding_Discriminant (Disc))
8762 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
8764 Next_Discriminant (Disc);
8767 end Set_Discriminant_Name;
8769 -- Start of processing for Build_Underlying_Full_View
8772 if Nkind (N) = N_Full_Type_Declaration then
8773 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
8775 elsif Nkind (N) = N_Subtype_Declaration then
8776 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
8778 elsif Nkind (N) = N_Component_Declaration then
8781 (Constraint (Subtype_Indication (Component_Definition (N))));
8784 raise Program_Error;
8787 C := First (Constraints (Constr));
8788 while Present (C) loop
8789 if Nkind (C) = N_Discriminant_Association then
8790 Id := First (Selector_Names (C));
8791 while Present (Id) loop
8792 Set_Discriminant_Name (Id);
8801 Make_Subtype_Declaration (Loc,
8802 Defining_Identifier => Subt,
8803 Subtype_Indication =>
8804 Make_Subtype_Indication (Loc,
8805 Subtype_Mark => New_Reference_To (Par, Loc),
8806 Constraint => New_Copy_Tree (Constr)));
8808 -- If this is a component subtype for an outer itype, it is not
8809 -- a list member, so simply set the parent link for analysis: if
8810 -- the enclosing type does not need to be in a declarative list,
8811 -- neither do the components.
8813 if Is_List_Member (N)
8814 and then Nkind (N) /= N_Component_Declaration
8816 Insert_Before (N, Indic);
8818 Set_Parent (Indic, Parent (N));
8822 Set_Underlying_Full_View (Typ, Full_View (Subt));
8823 end Build_Underlying_Full_View;
8825 -------------------------------
8826 -- Check_Abstract_Overriding --
8827 -------------------------------
8829 procedure Check_Abstract_Overriding (T : Entity_Id) is
8830 Alias_Subp : Entity_Id;
8836 procedure Check_Pragma_Implemented (Subp : Entity_Id);
8837 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
8838 -- which has pragma Implemented already set. Check whether Subp's entity
8839 -- kind conforms to the implementation kind of the overridden routine.
8841 procedure Check_Pragma_Implemented
8843 Iface_Subp : Entity_Id);
8844 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
8845 -- Iface_Subp and both entities have pragma Implemented already set on
8846 -- them. Check whether the two implementation kinds are conforming.
8848 procedure Inherit_Pragma_Implemented
8850 Iface_Subp : Entity_Id);
8851 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
8852 -- subprogram Iface_Subp which has been marked by pragma Implemented.
8853 -- Propagate the implementation kind of Iface_Subp to Subp.
8855 ------------------------------
8856 -- Check_Pragma_Implemented --
8857 ------------------------------
8859 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
8860 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
8861 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
8862 Contr_Typ : Entity_Id;
8865 -- Subp must have an alias since it is a hidden entity used to link
8866 -- an interface subprogram to its overriding counterpart.
8868 pragma Assert (Present (Alias (Subp)));
8870 -- Extract the type of the controlling formal
8872 Contr_Typ := Etype (First_Formal (Alias (Subp)));
8874 if Is_Concurrent_Record_Type (Contr_Typ) then
8875 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
8878 -- An interface subprogram whose implementation kind is By_Entry must
8879 -- be implemented by an entry.
8881 if Impl_Kind = Name_By_Entry
8882 and then Ekind (Wrapped_Entity (Alias (Subp))) /= E_Entry
8884 Error_Msg_Node_2 := Iface_Alias;
8886 ("type & must implement abstract subprogram & with an entry",
8887 Alias (Subp), Contr_Typ);
8889 elsif Impl_Kind = Name_By_Protected_Procedure then
8891 -- An interface subprogram whose implementation kind is By_
8892 -- Protected_Procedure cannot be implemented by a primitive
8893 -- procedure of a task type.
8895 if Ekind (Contr_Typ) /= E_Protected_Type then
8896 Error_Msg_Node_2 := Contr_Typ;
8898 ("interface subprogram & cannot be implemented by a " &
8899 "primitive procedure of task type &", Alias (Subp),
8902 -- An interface subprogram whose implementation kind is By_
8903 -- Protected_Procedure must be implemented by a procedure.
8905 elsif Is_Primitive_Wrapper (Alias (Subp))
8906 and then Ekind (Wrapped_Entity (Alias (Subp))) /= E_Procedure
8908 Error_Msg_Node_2 := Iface_Alias;
8910 ("type & must implement abstract subprogram & with a " &
8911 "procedure", Alias (Subp), Contr_Typ);
8914 end Check_Pragma_Implemented;
8916 ------------------------------
8917 -- Check_Pragma_Implemented --
8918 ------------------------------
8920 procedure Check_Pragma_Implemented
8922 Iface_Subp : Entity_Id)
8924 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
8925 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
8928 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
8929 -- and overriding subprogram are different. In general this is an
8930 -- error except when the implementation kind of the overridden
8931 -- subprograms is By_Any.
8933 if Iface_Kind /= Subp_Kind
8934 and then Iface_Kind /= Name_By_Any
8936 if Iface_Kind = Name_By_Entry then
8938 ("incompatible implementation kind, overridden subprogram " &
8939 "is marked By_Entry", Subp);
8942 ("incompatible implementation kind, overridden subprogram " &
8943 "is marked By_Protected_Procedure", Subp);
8946 end Check_Pragma_Implemented;
8948 --------------------------------
8949 -- Inherit_Pragma_Implemented --
8950 --------------------------------
8952 procedure Inherit_Pragma_Implemented
8954 Iface_Subp : Entity_Id)
8956 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
8957 Loc : constant Source_Ptr := Sloc (Subp);
8958 Impl_Prag : Node_Id;
8961 -- Since the implementation kind is stored as a representation item
8962 -- rather than a flag, create a pragma node.
8966 Chars => Name_Implemented,
8967 Pragma_Argument_Associations => New_List (
8968 Make_Pragma_Argument_Association (Loc,
8970 New_Reference_To (Subp, Loc)),
8972 Make_Pragma_Argument_Association (Loc,
8973 Expression => Make_Identifier (Loc, Iface_Kind))));
8975 -- The pragma doesn't need to be analyzed because it is internally
8976 -- build. It is safe to directly register it as a rep item since we
8977 -- are only interested in the characters of the implementation kind.
8979 Record_Rep_Item (Subp, Impl_Prag);
8980 end Inherit_Pragma_Implemented;
8982 -- Start of processing for Check_Abstract_Overriding
8985 Op_List := Primitive_Operations (T);
8987 -- Loop to check primitive operations
8989 Elmt := First_Elmt (Op_List);
8990 while Present (Elmt) loop
8991 Subp := Node (Elmt);
8992 Alias_Subp := Alias (Subp);
8994 -- Inherited subprograms are identified by the fact that they do not
8995 -- come from source, and the associated source location is the
8996 -- location of the first subtype of the derived type.
8998 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
8999 -- subprograms that "require overriding".
9001 -- Special exception, do not complain about failure to override the
9002 -- stream routines _Input and _Output, as well as the primitive
9003 -- operations used in dispatching selects since we always provide
9004 -- automatic overridings for these subprograms.
9006 -- Also ignore this rule for convention CIL since .NET libraries
9007 -- do bizarre things with interfaces???
9009 -- The partial view of T may have been a private extension, for
9010 -- which inherited functions dispatching on result are abstract.
9011 -- If the full view is a null extension, there is no need for
9012 -- overriding in Ada2005, but wrappers need to be built for them
9013 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
9015 if Is_Null_Extension (T)
9016 and then Has_Controlling_Result (Subp)
9017 and then Ada_Version >= Ada_2005
9018 and then Present (Alias_Subp)
9019 and then not Comes_From_Source (Subp)
9020 and then not Is_Abstract_Subprogram (Alias_Subp)
9021 and then not Is_Access_Type (Etype (Subp))
9025 -- Ada 2005 (AI-251): Internal entities of interfaces need no
9026 -- processing because this check is done with the aliased
9029 elsif Present (Interface_Alias (Subp)) then
9032 elsif (Is_Abstract_Subprogram (Subp)
9033 or else Requires_Overriding (Subp)
9035 (Has_Controlling_Result (Subp)
9036 and then Present (Alias_Subp)
9037 and then not Comes_From_Source (Subp)
9038 and then Sloc (Subp) = Sloc (First_Subtype (T))))
9039 and then not Is_TSS (Subp, TSS_Stream_Input)
9040 and then not Is_TSS (Subp, TSS_Stream_Output)
9041 and then not Is_Abstract_Type (T)
9042 and then Convention (T) /= Convention_CIL
9043 and then not Is_Predefined_Interface_Primitive (Subp)
9045 -- Ada 2005 (AI-251): Do not consider hidden entities associated
9046 -- with abstract interface types because the check will be done
9047 -- with the aliased entity (otherwise we generate a duplicated
9050 and then not Present (Interface_Alias (Subp))
9052 if Present (Alias_Subp) then
9054 -- Only perform the check for a derived subprogram when the
9055 -- type has an explicit record extension. This avoids incorrect
9056 -- flagging of abstract subprograms for the case of a type
9057 -- without an extension that is derived from a formal type
9058 -- with a tagged actual (can occur within a private part).
9060 -- Ada 2005 (AI-391): In the case of an inherited function with
9061 -- a controlling result of the type, the rule does not apply if
9062 -- the type is a null extension (unless the parent function
9063 -- itself is abstract, in which case the function must still be
9064 -- be overridden). The expander will generate an overriding
9065 -- wrapper function calling the parent subprogram (see
9066 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
9068 Type_Def := Type_Definition (Parent (T));
9070 if Nkind (Type_Def) = N_Derived_Type_Definition
9071 and then Present (Record_Extension_Part (Type_Def))
9073 (Ada_Version < Ada_2005
9074 or else not Is_Null_Extension (T)
9075 or else Ekind (Subp) = E_Procedure
9076 or else not Has_Controlling_Result (Subp)
9077 or else Is_Abstract_Subprogram (Alias_Subp)
9078 or else Requires_Overriding (Subp)
9079 or else Is_Access_Type (Etype (Subp)))
9081 -- Avoid reporting error in case of abstract predefined
9082 -- primitive inherited from interface type because the
9083 -- body of internally generated predefined primitives
9084 -- of tagged types are generated later by Freeze_Type
9086 if Is_Interface (Root_Type (T))
9087 and then Is_Abstract_Subprogram (Subp)
9088 and then Is_Predefined_Dispatching_Operation (Subp)
9089 and then not Comes_From_Source (Ultimate_Alias (Subp))
9095 ("type must be declared abstract or & overridden",
9098 -- Traverse the whole chain of aliased subprograms to
9099 -- complete the error notification. This is especially
9100 -- useful for traceability of the chain of entities when
9101 -- the subprogram corresponds with an interface
9102 -- subprogram (which may be defined in another package).
9104 if Present (Alias_Subp) then
9110 while Present (Alias (E)) loop
9111 Error_Msg_Sloc := Sloc (E);
9113 ("\& has been inherited #", T, Subp);
9117 Error_Msg_Sloc := Sloc (E);
9119 ("\& has been inherited from subprogram #",
9125 -- Ada 2005 (AI-345): Protected or task type implementing
9126 -- abstract interfaces.
9128 elsif Is_Concurrent_Record_Type (T)
9129 and then Present (Interfaces (T))
9131 -- The controlling formal of Subp must be of mode "out",
9132 -- "in out" or an access-to-variable to be overridden.
9134 -- Error message below needs rewording (remember comma
9135 -- in -gnatj mode) ???
9137 if Ekind (First_Formal (Subp)) = E_In_Parameter
9138 and then Ekind (Subp) /= E_Function
9140 if not Is_Predefined_Dispatching_Operation (Subp) then
9142 ("first formal of & must be of mode `OUT`, " &
9143 "`IN OUT` or access-to-variable", T, Subp);
9145 ("\to be overridden by protected procedure or " &
9146 "entry (RM 9.4(11.9/2))", T);
9149 -- Some other kind of overriding failure
9153 ("interface subprogram & must be overridden",
9156 -- Examine primitive operations of synchronized type,
9157 -- to find homonyms that have the wrong profile.
9164 First_Entity (Corresponding_Concurrent_Type (T));
9165 while Present (Prim) loop
9166 if Chars (Prim) = Chars (Subp) then
9168 ("profile is not type conformant with "
9169 & "prefixed view profile of "
9170 & "inherited operation&", Prim, Subp);
9180 Error_Msg_Node_2 := T;
9182 ("abstract subprogram& not allowed for type&", Subp);
9184 -- Also post unconditional warning on the type (unconditional
9185 -- so that if there are more than one of these cases, we get
9186 -- them all, and not just the first one).
9188 Error_Msg_Node_2 := Subp;
9189 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
9193 -- Ada 2012 (AI05-0030): Perform some checks related to pragma
9196 -- Subp is an expander-generated procedure which maps an interface
9197 -- alias to a protected wrapper. The interface alias is flagged by
9198 -- pragma Implemented. Ensure that Subp is a procedure when the
9199 -- implementation kind is By_Protected_Procedure or an entry when
9202 if Ada_Version >= Ada_2012
9203 and then Is_Hidden (Subp)
9204 and then Present (Interface_Alias (Subp))
9205 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
9207 Check_Pragma_Implemented (Subp);
9210 -- Subp is an interface primitive which overrides another interface
9211 -- primitive marked with pragma Implemented.
9213 if Ada_Version >= Ada_2012
9214 and then Present (Overridden_Operation (Subp))
9215 and then Has_Rep_Pragma
9216 (Overridden_Operation (Subp), Name_Implemented)
9218 -- If the overriding routine is also marked by Implemented, check
9219 -- that the two implementation kinds are conforming.
9221 if Has_Rep_Pragma (Subp, Name_Implemented) then
9222 Check_Pragma_Implemented
9224 Iface_Subp => Overridden_Operation (Subp));
9226 -- Otherwise the overriding routine inherits the implementation
9227 -- kind from the overridden subprogram.
9230 Inherit_Pragma_Implemented
9232 Iface_Subp => Overridden_Operation (Subp));
9238 end Check_Abstract_Overriding;
9240 ------------------------------------------------
9241 -- Check_Access_Discriminant_Requires_Limited --
9242 ------------------------------------------------
9244 procedure Check_Access_Discriminant_Requires_Limited
9249 -- A discriminant_specification for an access discriminant shall appear
9250 -- only in the declaration for a task or protected type, or for a type
9251 -- with the reserved word 'limited' in its definition or in one of its
9252 -- ancestors (RM 3.7(10)).
9254 -- AI-0063: The proper condition is that type must be immutably limited,
9255 -- or else be a partial view.
9257 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
9258 if Is_Immutably_Limited_Type (Current_Scope)
9260 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
9261 and then Limited_Present (Parent (Current_Scope)))
9267 ("access discriminants allowed only for limited types", Loc);
9270 end Check_Access_Discriminant_Requires_Limited;
9272 -----------------------------------
9273 -- Check_Aliased_Component_Types --
9274 -----------------------------------
9276 procedure Check_Aliased_Component_Types (T : Entity_Id) is
9280 -- ??? Also need to check components of record extensions, but not
9281 -- components of protected types (which are always limited).
9283 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
9284 -- types to be unconstrained. This is safe because it is illegal to
9285 -- create access subtypes to such types with explicit discriminant
9288 if not Is_Limited_Type (T) then
9289 if Ekind (T) = E_Record_Type then
9290 C := First_Component (T);
9291 while Present (C) loop
9293 and then Has_Discriminants (Etype (C))
9294 and then not Is_Constrained (Etype (C))
9295 and then not In_Instance_Body
9296 and then Ada_Version < Ada_2005
9299 ("aliased component must be constrained (RM 3.6(11))",
9306 elsif Ekind (T) = E_Array_Type then
9307 if Has_Aliased_Components (T)
9308 and then Has_Discriminants (Component_Type (T))
9309 and then not Is_Constrained (Component_Type (T))
9310 and then not In_Instance_Body
9311 and then Ada_Version < Ada_2005
9314 ("aliased component type must be constrained (RM 3.6(11))",
9319 end Check_Aliased_Component_Types;
9321 ----------------------
9322 -- Check_Completion --
9323 ----------------------
9325 procedure Check_Completion (Body_Id : Node_Id := Empty) is
9328 procedure Post_Error;
9329 -- Post error message for lack of completion for entity E
9335 procedure Post_Error is
9337 procedure Missing_Body;
9338 -- Output missing body message
9344 procedure Missing_Body is
9346 -- Spec is in same unit, so we can post on spec
9348 if In_Same_Source_Unit (Body_Id, E) then
9349 Error_Msg_N ("missing body for &", E);
9351 -- Spec is in a separate unit, so we have to post on the body
9354 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
9358 -- Start of processing for Post_Error
9361 if not Comes_From_Source (E) then
9363 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
9364 -- It may be an anonymous protected type created for a
9365 -- single variable. Post error on variable, if present.
9371 Var := First_Entity (Current_Scope);
9372 while Present (Var) loop
9373 exit when Etype (Var) = E
9374 and then Comes_From_Source (Var);
9379 if Present (Var) then
9386 -- If a generated entity has no completion, then either previous
9387 -- semantic errors have disabled the expansion phase, or else we had
9388 -- missing subunits, or else we are compiling without expansion,
9389 -- or else something is very wrong.
9391 if not Comes_From_Source (E) then
9393 (Serious_Errors_Detected > 0
9394 or else Configurable_Run_Time_Violations > 0
9395 or else Subunits_Missing
9396 or else not Expander_Active);
9399 -- Here for source entity
9402 -- Here if no body to post the error message, so we post the error
9403 -- on the declaration that has no completion. This is not really
9404 -- the right place to post it, think about this later ???
9406 if No (Body_Id) then
9409 ("missing full declaration for }", Parent (E), E);
9411 Error_Msg_NE ("missing body for &", Parent (E), E);
9414 -- Package body has no completion for a declaration that appears
9415 -- in the corresponding spec. Post error on the body, with a
9416 -- reference to the non-completed declaration.
9419 Error_Msg_Sloc := Sloc (E);
9422 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
9424 elsif Is_Overloadable (E)
9425 and then Current_Entity_In_Scope (E) /= E
9427 -- It may be that the completion is mistyped and appears as
9428 -- a distinct overloading of the entity.
9431 Candidate : constant Entity_Id :=
9432 Current_Entity_In_Scope (E);
9433 Decl : constant Node_Id :=
9434 Unit_Declaration_Node (Candidate);
9437 if Is_Overloadable (Candidate)
9438 and then Ekind (Candidate) = Ekind (E)
9439 and then Nkind (Decl) = N_Subprogram_Body
9440 and then Acts_As_Spec (Decl)
9442 Check_Type_Conformant (Candidate, E);
9456 -- Start of processing for Check_Completion
9459 E := First_Entity (Current_Scope);
9460 while Present (E) loop
9461 if Is_Intrinsic_Subprogram (E) then
9464 -- The following situation requires special handling: a child unit
9465 -- that appears in the context clause of the body of its parent:
9467 -- procedure Parent.Child (...);
9469 -- with Parent.Child;
9470 -- package body Parent is
9472 -- Here Parent.Child appears as a local entity, but should not be
9473 -- flagged as requiring completion, because it is a compilation
9476 -- Ignore missing completion for a subprogram that does not come from
9477 -- source (including the _Call primitive operation of RAS types,
9478 -- which has to have the flag Comes_From_Source for other purposes):
9479 -- we assume that the expander will provide the missing completion.
9480 -- In case of previous errors, other expansion actions that provide
9481 -- bodies for null procedures with not be invoked, so inhibit message
9483 -- Note that E_Operator is not in the list that follows, because
9484 -- this kind is reserved for predefined operators, that are
9485 -- intrinsic and do not need completion.
9487 elsif Ekind (E) = E_Function
9488 or else Ekind (E) = E_Procedure
9489 or else Ekind (E) = E_Generic_Function
9490 or else Ekind (E) = E_Generic_Procedure
9492 if Has_Completion (E) then
9495 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
9498 elsif Is_Subprogram (E)
9499 and then (not Comes_From_Source (E)
9500 or else Chars (E) = Name_uCall)
9505 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
9509 elsif Nkind (Parent (E)) = N_Procedure_Specification
9510 and then Null_Present (Parent (E))
9511 and then Serious_Errors_Detected > 0
9519 elsif Is_Entry (E) then
9520 if not Has_Completion (E) and then
9521 (Ekind (Scope (E)) = E_Protected_Object
9522 or else Ekind (Scope (E)) = E_Protected_Type)
9527 elsif Is_Package_Or_Generic_Package (E) then
9528 if Unit_Requires_Body (E) then
9529 if not Has_Completion (E)
9530 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
9536 elsif not Is_Child_Unit (E) then
9537 May_Need_Implicit_Body (E);
9540 elsif Ekind (E) = E_Incomplete_Type
9541 and then No (Underlying_Type (E))
9545 elsif (Ekind (E) = E_Task_Type or else
9546 Ekind (E) = E_Protected_Type)
9547 and then not Has_Completion (E)
9551 -- A single task declared in the current scope is a constant, verify
9552 -- that the body of its anonymous type is in the same scope. If the
9553 -- task is defined elsewhere, this may be a renaming declaration for
9554 -- which no completion is needed.
9556 elsif Ekind (E) = E_Constant
9557 and then Ekind (Etype (E)) = E_Task_Type
9558 and then not Has_Completion (Etype (E))
9559 and then Scope (Etype (E)) = Current_Scope
9563 elsif Ekind (E) = E_Protected_Object
9564 and then not Has_Completion (Etype (E))
9568 elsif Ekind (E) = E_Record_Type then
9569 if Is_Tagged_Type (E) then
9570 Check_Abstract_Overriding (E);
9571 Check_Conventions (E);
9574 Check_Aliased_Component_Types (E);
9576 elsif Ekind (E) = E_Array_Type then
9577 Check_Aliased_Component_Types (E);
9583 end Check_Completion;
9585 ----------------------------
9586 -- Check_Delta_Expression --
9587 ----------------------------
9589 procedure Check_Delta_Expression (E : Node_Id) is
9591 if not (Is_Real_Type (Etype (E))) then
9592 Wrong_Type (E, Any_Real);
9594 elsif not Is_OK_Static_Expression (E) then
9595 Flag_Non_Static_Expr
9596 ("non-static expression used for delta value!", E);
9598 elsif not UR_Is_Positive (Expr_Value_R (E)) then
9599 Error_Msg_N ("delta expression must be positive", E);
9605 -- If any of above errors occurred, then replace the incorrect
9606 -- expression by the real 0.1, which should prevent further errors.
9609 Make_Real_Literal (Sloc (E), Ureal_Tenth));
9610 Analyze_And_Resolve (E, Standard_Float);
9611 end Check_Delta_Expression;
9613 -----------------------------
9614 -- Check_Digits_Expression --
9615 -----------------------------
9617 procedure Check_Digits_Expression (E : Node_Id) is
9619 if not (Is_Integer_Type (Etype (E))) then
9620 Wrong_Type (E, Any_Integer);
9622 elsif not Is_OK_Static_Expression (E) then
9623 Flag_Non_Static_Expr
9624 ("non-static expression used for digits value!", E);
9626 elsif Expr_Value (E) <= 0 then
9627 Error_Msg_N ("digits value must be greater than zero", E);
9633 -- If any of above errors occurred, then replace the incorrect
9634 -- expression by the integer 1, which should prevent further errors.
9636 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
9637 Analyze_And_Resolve (E, Standard_Integer);
9639 end Check_Digits_Expression;
9641 --------------------------
9642 -- Check_Initialization --
9643 --------------------------
9645 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
9647 if Is_Limited_Type (T)
9648 and then not In_Instance
9649 and then not In_Inlined_Body
9651 if not OK_For_Limited_Init (T, Exp) then
9653 -- In GNAT mode, this is just a warning, to allow it to be evilly
9654 -- turned off. Otherwise it is a real error.
9658 ("?cannot initialize entities of limited type!", Exp);
9660 elsif Ada_Version < Ada_2005 then
9662 ("cannot initialize entities of limited type", Exp);
9663 Explain_Limited_Type (T, Exp);
9666 -- Specialize error message according to kind of illegal
9667 -- initial expression.
9669 if Nkind (Exp) = N_Type_Conversion
9670 and then Nkind (Expression (Exp)) = N_Function_Call
9673 ("illegal context for call"
9674 & " to function with limited result", Exp);
9678 ("initialization of limited object requires aggregate "
9679 & "or function call", Exp);
9684 end Check_Initialization;
9686 ----------------------
9687 -- Check_Interfaces --
9688 ----------------------
9690 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
9691 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
9694 Iface_Def : Node_Id;
9695 Iface_Typ : Entity_Id;
9696 Parent_Node : Node_Id;
9698 Is_Task : Boolean := False;
9699 -- Set True if parent type or any progenitor is a task interface
9701 Is_Protected : Boolean := False;
9702 -- Set True if parent type or any progenitor is a protected interface
9704 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
9705 -- Check that a progenitor is compatible with declaration.
9706 -- Error is posted on Error_Node.
9712 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
9713 Iface_Id : constant Entity_Id :=
9714 Defining_Identifier (Parent (Iface_Def));
9718 if Nkind (N) = N_Private_Extension_Declaration then
9721 Type_Def := Type_Definition (N);
9724 if Is_Task_Interface (Iface_Id) then
9727 elsif Is_Protected_Interface (Iface_Id) then
9728 Is_Protected := True;
9731 if Is_Synchronized_Interface (Iface_Id) then
9733 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
9734 -- extension derived from a synchronized interface must explicitly
9735 -- be declared synchronized, because the full view will be a
9736 -- synchronized type.
9738 if Nkind (N) = N_Private_Extension_Declaration then
9739 if not Synchronized_Present (N) then
9741 ("private extension of& must be explicitly synchronized",
9745 -- However, by 3.9.4(16/2), a full type that is a record extension
9746 -- is never allowed to derive from a synchronized interface (note
9747 -- that interfaces must be excluded from this check, because those
9748 -- are represented by derived type definitions in some cases).
9750 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9751 and then not Interface_Present (Type_Definition (N))
9753 Error_Msg_N ("record extension cannot derive from synchronized"
9754 & " interface", Error_Node);
9758 -- Check that the characteristics of the progenitor are compatible
9759 -- with the explicit qualifier in the declaration.
9760 -- The check only applies to qualifiers that come from source.
9761 -- Limited_Present also appears in the declaration of corresponding
9762 -- records, and the check does not apply to them.
9764 if Limited_Present (Type_Def)
9766 Is_Concurrent_Record_Type (Defining_Identifier (N))
9768 if Is_Limited_Interface (Parent_Type)
9769 and then not Is_Limited_Interface (Iface_Id)
9772 ("progenitor& must be limited interface",
9773 Error_Node, Iface_Id);
9776 (Task_Present (Iface_Def)
9777 or else Protected_Present (Iface_Def)
9778 or else Synchronized_Present (Iface_Def))
9779 and then Nkind (N) /= N_Private_Extension_Declaration
9780 and then not Error_Posted (N)
9783 ("progenitor& must be limited interface",
9784 Error_Node, Iface_Id);
9787 -- Protected interfaces can only inherit from limited, synchronized
9788 -- or protected interfaces.
9790 elsif Nkind (N) = N_Full_Type_Declaration
9791 and then Protected_Present (Type_Def)
9793 if Limited_Present (Iface_Def)
9794 or else Synchronized_Present (Iface_Def)
9795 or else Protected_Present (Iface_Def)
9799 elsif Task_Present (Iface_Def) then
9800 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9801 & " from task interface", Error_Node);
9804 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9805 & " from non-limited interface", Error_Node);
9808 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
9809 -- limited and synchronized.
9811 elsif Synchronized_Present (Type_Def) then
9812 if Limited_Present (Iface_Def)
9813 or else Synchronized_Present (Iface_Def)
9817 elsif Protected_Present (Iface_Def)
9818 and then Nkind (N) /= N_Private_Extension_Declaration
9820 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9821 & " from protected interface", Error_Node);
9823 elsif Task_Present (Iface_Def)
9824 and then Nkind (N) /= N_Private_Extension_Declaration
9826 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9827 & " from task interface", Error_Node);
9829 elsif not Is_Limited_Interface (Iface_Id) then
9830 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9831 & " from non-limited interface", Error_Node);
9834 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
9835 -- synchronized or task interfaces.
9837 elsif Nkind (N) = N_Full_Type_Declaration
9838 and then Task_Present (Type_Def)
9840 if Limited_Present (Iface_Def)
9841 or else Synchronized_Present (Iface_Def)
9842 or else Task_Present (Iface_Def)
9846 elsif Protected_Present (Iface_Def) then
9847 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9848 & " protected interface", Error_Node);
9851 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9852 & " non-limited interface", Error_Node);
9857 -- Start of processing for Check_Interfaces
9860 if Is_Interface (Parent_Type) then
9861 if Is_Task_Interface (Parent_Type) then
9864 elsif Is_Protected_Interface (Parent_Type) then
9865 Is_Protected := True;
9869 if Nkind (N) = N_Private_Extension_Declaration then
9871 -- Check that progenitors are compatible with declaration
9873 Iface := First (Interface_List (Def));
9874 while Present (Iface) loop
9875 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9877 Parent_Node := Parent (Base_Type (Iface_Typ));
9878 Iface_Def := Type_Definition (Parent_Node);
9880 if not Is_Interface (Iface_Typ) then
9881 Diagnose_Interface (Iface, Iface_Typ);
9884 Check_Ifaces (Iface_Def, Iface);
9890 if Is_Task and Is_Protected then
9892 ("type cannot derive from task and protected interface", N);
9898 -- Full type declaration of derived type.
9899 -- Check compatibility with parent if it is interface type
9901 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9902 and then Is_Interface (Parent_Type)
9904 Parent_Node := Parent (Parent_Type);
9906 -- More detailed checks for interface varieties
9909 (Iface_Def => Type_Definition (Parent_Node),
9910 Error_Node => Subtype_Indication (Type_Definition (N)));
9913 Iface := First (Interface_List (Def));
9914 while Present (Iface) loop
9915 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9917 Parent_Node := Parent (Base_Type (Iface_Typ));
9918 Iface_Def := Type_Definition (Parent_Node);
9920 if not Is_Interface (Iface_Typ) then
9921 Diagnose_Interface (Iface, Iface_Typ);
9924 -- "The declaration of a specific descendant of an interface
9925 -- type freezes the interface type" RM 13.14
9927 Freeze_Before (N, Iface_Typ);
9928 Check_Ifaces (Iface_Def, Error_Node => Iface);
9934 if Is_Task and Is_Protected then
9936 ("type cannot derive from task and protected interface", N);
9938 end Check_Interfaces;
9940 ------------------------------------
9941 -- Check_Or_Process_Discriminants --
9942 ------------------------------------
9944 -- If an incomplete or private type declaration was already given for the
9945 -- type, the discriminants may have already been processed if they were
9946 -- present on the incomplete declaration. In this case a full conformance
9947 -- check has been performed in Find_Type_Name, and we then recheck here
9948 -- some properties that can't be checked on the partial view alone.
9949 -- Otherwise we call Process_Discriminants.
9951 procedure Check_Or_Process_Discriminants
9954 Prev : Entity_Id := Empty)
9957 if Has_Discriminants (T) then
9959 -- Discriminants are already set on T if they were already present
9960 -- on the partial view. Make them visible to component declarations.
9964 -- Discriminant on T (full view) referencing expr on partial view
9967 -- Entity of corresponding discriminant on partial view
9970 -- Discriminant specification for full view, expression is the
9971 -- syntactic copy on full view (which has been checked for
9972 -- conformance with partial view), only used here to post error
9976 D := First_Discriminant (T);
9977 New_D := First (Discriminant_Specifications (N));
9978 while Present (D) loop
9979 Prev_D := Current_Entity (D);
9980 Set_Current_Entity (D);
9981 Set_Is_Immediately_Visible (D);
9982 Set_Homonym (D, Prev_D);
9984 -- Handle the case where there is an untagged partial view and
9985 -- the full view is tagged: must disallow discriminants with
9986 -- defaults, unless compiling for Ada 2012, which allows a
9987 -- limited tagged type to have defaulted discriminants (see
9988 -- AI05-0214). However, suppress the error here if it was
9989 -- already reported on the default expression of the partial
9992 if Is_Tagged_Type (T)
9993 and then Present (Expression (Parent (D)))
9994 and then (not Is_Limited_Type (Current_Scope)
9995 or else Ada_Version < Ada_2012)
9996 and then not Error_Posted (Expression (Parent (D)))
9998 if Ada_Version >= Ada_2012 then
10000 ("discriminants of nonlimited tagged type cannot have"
10002 Expression (New_D));
10005 ("discriminants of tagged type cannot have defaults",
10006 Expression (New_D));
10010 -- Ada 2005 (AI-230): Access discriminant allowed in
10011 -- non-limited record types.
10013 if Ada_Version < Ada_2005 then
10015 -- This restriction gets applied to the full type here. It
10016 -- has already been applied earlier to the partial view.
10018 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
10021 Next_Discriminant (D);
10026 elsif Present (Discriminant_Specifications (N)) then
10027 Process_Discriminants (N, Prev);
10029 end Check_Or_Process_Discriminants;
10031 ----------------------
10032 -- Check_Real_Bound --
10033 ----------------------
10035 procedure Check_Real_Bound (Bound : Node_Id) is
10037 if not Is_Real_Type (Etype (Bound)) then
10039 ("bound in real type definition must be of real type", Bound);
10041 elsif not Is_OK_Static_Expression (Bound) then
10042 Flag_Non_Static_Expr
10043 ("non-static expression used for real type bound!", Bound);
10050 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
10052 Resolve (Bound, Standard_Float);
10053 end Check_Real_Bound;
10055 ------------------------------
10056 -- Complete_Private_Subtype --
10057 ------------------------------
10059 procedure Complete_Private_Subtype
10062 Full_Base : Entity_Id;
10063 Related_Nod : Node_Id)
10065 Save_Next_Entity : Entity_Id;
10066 Save_Homonym : Entity_Id;
10069 -- Set semantic attributes for (implicit) private subtype completion.
10070 -- If the full type has no discriminants, then it is a copy of the full
10071 -- view of the base. Otherwise, it is a subtype of the base with a
10072 -- possible discriminant constraint. Save and restore the original
10073 -- Next_Entity field of full to ensure that the calls to Copy_Node
10074 -- do not corrupt the entity chain.
10076 -- Note that the type of the full view is the same entity as the type of
10077 -- the partial view. In this fashion, the subtype has access to the
10078 -- correct view of the parent.
10080 Save_Next_Entity := Next_Entity (Full);
10081 Save_Homonym := Homonym (Priv);
10083 case Ekind (Full_Base) is
10084 when E_Record_Type |
10090 Copy_Node (Priv, Full);
10092 Set_Has_Discriminants (Full, Has_Discriminants (Full_Base));
10093 Set_First_Entity (Full, First_Entity (Full_Base));
10094 Set_Last_Entity (Full, Last_Entity (Full_Base));
10097 Copy_Node (Full_Base, Full);
10098 Set_Chars (Full, Chars (Priv));
10099 Conditional_Delay (Full, Priv);
10100 Set_Sloc (Full, Sloc (Priv));
10103 Set_Next_Entity (Full, Save_Next_Entity);
10104 Set_Homonym (Full, Save_Homonym);
10105 Set_Associated_Node_For_Itype (Full, Related_Nod);
10107 -- Set common attributes for all subtypes: kind, convention, etc.
10109 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
10110 Set_Convention (Full, Convention (Full_Base));
10112 -- The Etype of the full view is inconsistent. Gigi needs to see the
10113 -- structural full view, which is what the current scheme gives:
10114 -- the Etype of the full view is the etype of the full base. However,
10115 -- if the full base is a derived type, the full view then looks like
10116 -- a subtype of the parent, not a subtype of the full base. If instead
10119 -- Set_Etype (Full, Full_Base);
10121 -- then we get inconsistencies in the front-end (confusion between
10122 -- views). Several outstanding bugs are related to this ???
10124 Set_Is_First_Subtype (Full, False);
10125 Set_Scope (Full, Scope (Priv));
10126 Set_Size_Info (Full, Full_Base);
10127 Set_RM_Size (Full, RM_Size (Full_Base));
10128 Set_Is_Itype (Full);
10130 -- A subtype of a private-type-without-discriminants, whose full-view
10131 -- has discriminants with default expressions, is not constrained!
10133 if not Has_Discriminants (Priv) then
10134 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
10136 if Has_Discriminants (Full_Base) then
10137 Set_Discriminant_Constraint
10138 (Full, Discriminant_Constraint (Full_Base));
10140 -- The partial view may have been indefinite, the full view
10143 Set_Has_Unknown_Discriminants
10144 (Full, Has_Unknown_Discriminants (Full_Base));
10148 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
10149 Set_Depends_On_Private (Full, Has_Private_Component (Full));
10151 -- Freeze the private subtype entity if its parent is delayed, and not
10152 -- already frozen. We skip this processing if the type is an anonymous
10153 -- subtype of a record component, or is the corresponding record of a
10154 -- protected type, since ???
10156 if not Is_Type (Scope (Full)) then
10157 Set_Has_Delayed_Freeze (Full,
10158 Has_Delayed_Freeze (Full_Base)
10159 and then (not Is_Frozen (Full_Base)));
10162 Set_Freeze_Node (Full, Empty);
10163 Set_Is_Frozen (Full, False);
10164 Set_Full_View (Priv, Full);
10166 if Has_Discriminants (Full) then
10167 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
10168 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
10170 if Has_Unknown_Discriminants (Full) then
10171 Set_Discriminant_Constraint (Full, No_Elist);
10175 if Ekind (Full_Base) = E_Record_Type
10176 and then Has_Discriminants (Full_Base)
10177 and then Has_Discriminants (Priv) -- might not, if errors
10178 and then not Has_Unknown_Discriminants (Priv)
10179 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
10181 Create_Constrained_Components
10182 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
10184 -- If the full base is itself derived from private, build a congruent
10185 -- subtype of its underlying type, for use by the back end. For a
10186 -- constrained record component, the declaration cannot be placed on
10187 -- the component list, but it must nevertheless be built an analyzed, to
10188 -- supply enough information for Gigi to compute the size of component.
10190 elsif Ekind (Full_Base) in Private_Kind
10191 and then Is_Derived_Type (Full_Base)
10192 and then Has_Discriminants (Full_Base)
10193 and then (Ekind (Current_Scope) /= E_Record_Subtype)
10195 if not Is_Itype (Priv)
10197 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
10199 Build_Underlying_Full_View
10200 (Parent (Priv), Full, Etype (Full_Base));
10202 elsif Nkind (Related_Nod) = N_Component_Declaration then
10203 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
10206 elsif Is_Record_Type (Full_Base) then
10208 -- Show Full is simply a renaming of Full_Base
10210 Set_Cloned_Subtype (Full, Full_Base);
10213 -- It is unsafe to share to bounds of a scalar type, because the Itype
10214 -- is elaborated on demand, and if a bound is non-static then different
10215 -- orders of elaboration in different units will lead to different
10216 -- external symbols.
10218 if Is_Scalar_Type (Full_Base) then
10219 Set_Scalar_Range (Full,
10220 Make_Range (Sloc (Related_Nod),
10222 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
10224 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
10226 -- This completion inherits the bounds of the full parent, but if
10227 -- the parent is an unconstrained floating point type, so is the
10230 if Is_Floating_Point_Type (Full_Base) then
10231 Set_Includes_Infinities
10232 (Scalar_Range (Full), Has_Infinities (Full_Base));
10236 -- ??? It seems that a lot of fields are missing that should be copied
10237 -- from Full_Base to Full. Here are some that are introduced in a
10238 -- non-disruptive way but a cleanup is necessary.
10240 if Is_Tagged_Type (Full_Base) then
10241 Set_Is_Tagged_Type (Full);
10242 Set_Direct_Primitive_Operations (Full,
10243 Direct_Primitive_Operations (Full_Base));
10245 -- Inherit class_wide type of full_base in case the partial view was
10246 -- not tagged. Otherwise it has already been created when the private
10247 -- subtype was analyzed.
10249 if No (Class_Wide_Type (Full)) then
10250 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
10253 -- If this is a subtype of a protected or task type, constrain its
10254 -- corresponding record, unless this is a subtype without constraints,
10255 -- i.e. a simple renaming as with an actual subtype in an instance.
10257 elsif Is_Concurrent_Type (Full_Base) then
10258 if Has_Discriminants (Full)
10259 and then Present (Corresponding_Record_Type (Full_Base))
10261 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
10263 Set_Corresponding_Record_Type (Full,
10264 Constrain_Corresponding_Record
10265 (Full, Corresponding_Record_Type (Full_Base),
10266 Related_Nod, Full_Base));
10269 Set_Corresponding_Record_Type (Full,
10270 Corresponding_Record_Type (Full_Base));
10274 -- Link rep item chain, and also setting of Has_Predicates from private
10275 -- subtype to full subtype, since we will need these on the full subtype
10276 -- to create the predicate function. Note that the full subtype may
10277 -- already have rep items, inherited from the full view of the base
10278 -- type, so we must be sure not to overwrite these entries.
10282 Next_Item : Node_Id;
10285 Item := First_Rep_Item (Full);
10287 -- If no existing rep items on full type, we can just link directly
10288 -- to the list of items on the private type.
10291 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
10293 -- Otherwise, search to the end of items currently linked to the full
10294 -- subtype and append the private items to the end. However, if Priv
10295 -- and Full already have the same list of rep items, then the append
10296 -- is not done, as that would create a circularity.
10298 elsif Item /= First_Rep_Item (Priv) then
10300 Next_Item := Next_Rep_Item (Item);
10301 exit when No (Next_Item);
10305 -- And link the private type items at the end of the chain
10307 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
10311 -- Make sure Has_Predicates is set on full type if it is set on the
10312 -- private type. Note that it may already be set on the full type and
10313 -- if so, we don't want to unset it.
10315 if Has_Predicates (Priv) then
10316 Set_Has_Predicates (Full);
10318 end Complete_Private_Subtype;
10320 ----------------------------
10321 -- Constant_Redeclaration --
10322 ----------------------------
10324 procedure Constant_Redeclaration
10329 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
10330 Obj_Def : constant Node_Id := Object_Definition (N);
10333 procedure Check_Possible_Deferred_Completion
10334 (Prev_Id : Entity_Id;
10335 Prev_Obj_Def : Node_Id;
10336 Curr_Obj_Def : Node_Id);
10337 -- Determine whether the two object definitions describe the partial
10338 -- and the full view of a constrained deferred constant. Generate
10339 -- a subtype for the full view and verify that it statically matches
10340 -- the subtype of the partial view.
10342 procedure Check_Recursive_Declaration (Typ : Entity_Id);
10343 -- If deferred constant is an access type initialized with an allocator,
10344 -- check whether there is an illegal recursion in the definition,
10345 -- through a default value of some record subcomponent. This is normally
10346 -- detected when generating init procs, but requires this additional
10347 -- mechanism when expansion is disabled.
10349 ----------------------------------------
10350 -- Check_Possible_Deferred_Completion --
10351 ----------------------------------------
10353 procedure Check_Possible_Deferred_Completion
10354 (Prev_Id : Entity_Id;
10355 Prev_Obj_Def : Node_Id;
10356 Curr_Obj_Def : Node_Id)
10359 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
10360 and then Present (Constraint (Prev_Obj_Def))
10361 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
10362 and then Present (Constraint (Curr_Obj_Def))
10365 Loc : constant Source_Ptr := Sloc (N);
10366 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
10367 Decl : constant Node_Id :=
10368 Make_Subtype_Declaration (Loc,
10369 Defining_Identifier => Def_Id,
10370 Subtype_Indication =>
10371 Relocate_Node (Curr_Obj_Def));
10374 Insert_Before_And_Analyze (N, Decl);
10375 Set_Etype (Id, Def_Id);
10377 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
10378 Error_Msg_Sloc := Sloc (Prev_Id);
10379 Error_Msg_N ("subtype does not statically match deferred " &
10380 "declaration#", N);
10384 end Check_Possible_Deferred_Completion;
10386 ---------------------------------
10387 -- Check_Recursive_Declaration --
10388 ---------------------------------
10390 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
10394 if Is_Record_Type (Typ) then
10395 Comp := First_Component (Typ);
10396 while Present (Comp) loop
10397 if Comes_From_Source (Comp) then
10398 if Present (Expression (Parent (Comp)))
10399 and then Is_Entity_Name (Expression (Parent (Comp)))
10400 and then Entity (Expression (Parent (Comp))) = Prev
10402 Error_Msg_Sloc := Sloc (Parent (Comp));
10404 ("illegal circularity with declaration for&#",
10408 elsif Is_Record_Type (Etype (Comp)) then
10409 Check_Recursive_Declaration (Etype (Comp));
10413 Next_Component (Comp);
10416 end Check_Recursive_Declaration;
10418 -- Start of processing for Constant_Redeclaration
10421 if Nkind (Parent (Prev)) = N_Object_Declaration then
10422 if Nkind (Object_Definition
10423 (Parent (Prev))) = N_Subtype_Indication
10425 -- Find type of new declaration. The constraints of the two
10426 -- views must match statically, but there is no point in
10427 -- creating an itype for the full view.
10429 if Nkind (Obj_Def) = N_Subtype_Indication then
10430 Find_Type (Subtype_Mark (Obj_Def));
10431 New_T := Entity (Subtype_Mark (Obj_Def));
10434 Find_Type (Obj_Def);
10435 New_T := Entity (Obj_Def);
10441 -- The full view may impose a constraint, even if the partial
10442 -- view does not, so construct the subtype.
10444 New_T := Find_Type_Of_Object (Obj_Def, N);
10449 -- Current declaration is illegal, diagnosed below in Enter_Name
10455 -- If previous full declaration or a renaming declaration exists, or if
10456 -- a homograph is present, let Enter_Name handle it, either with an
10457 -- error or with the removal of an overridden implicit subprogram.
10459 if Ekind (Prev) /= E_Constant
10460 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
10461 or else Present (Expression (Parent (Prev)))
10462 or else Present (Full_View (Prev))
10466 -- Verify that types of both declarations match, or else that both types
10467 -- are anonymous access types whose designated subtypes statically match
10468 -- (as allowed in Ada 2005 by AI-385).
10470 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
10472 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
10473 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
10474 or else Is_Access_Constant (Etype (New_T)) /=
10475 Is_Access_Constant (Etype (Prev))
10476 or else Can_Never_Be_Null (Etype (New_T)) /=
10477 Can_Never_Be_Null (Etype (Prev))
10478 or else Null_Exclusion_Present (Parent (Prev)) /=
10479 Null_Exclusion_Present (Parent (Id))
10480 or else not Subtypes_Statically_Match
10481 (Designated_Type (Etype (Prev)),
10482 Designated_Type (Etype (New_T))))
10484 Error_Msg_Sloc := Sloc (Prev);
10485 Error_Msg_N ("type does not match declaration#", N);
10486 Set_Full_View (Prev, Id);
10487 Set_Etype (Id, Any_Type);
10490 Null_Exclusion_Present (Parent (Prev))
10491 and then not Null_Exclusion_Present (N)
10493 Error_Msg_Sloc := Sloc (Prev);
10494 Error_Msg_N ("null-exclusion does not match declaration#", N);
10495 Set_Full_View (Prev, Id);
10496 Set_Etype (Id, Any_Type);
10498 -- If so, process the full constant declaration
10501 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
10502 -- the deferred declaration is constrained, then the subtype defined
10503 -- by the subtype_indication in the full declaration shall match it
10506 Check_Possible_Deferred_Completion
10508 Prev_Obj_Def => Object_Definition (Parent (Prev)),
10509 Curr_Obj_Def => Obj_Def);
10511 Set_Full_View (Prev, Id);
10512 Set_Is_Public (Id, Is_Public (Prev));
10513 Set_Is_Internal (Id);
10514 Append_Entity (Id, Current_Scope);
10516 -- Check ALIASED present if present before (RM 7.4(7))
10518 if Is_Aliased (Prev)
10519 and then not Aliased_Present (N)
10521 Error_Msg_Sloc := Sloc (Prev);
10522 Error_Msg_N ("ALIASED required (see declaration#)", N);
10525 -- Check that placement is in private part and that the incomplete
10526 -- declaration appeared in the visible part.
10528 if Ekind (Current_Scope) = E_Package
10529 and then not In_Private_Part (Current_Scope)
10531 Error_Msg_Sloc := Sloc (Prev);
10533 ("full constant for declaration#"
10534 & " must be in private part", N);
10536 elsif Ekind (Current_Scope) = E_Package
10538 List_Containing (Parent (Prev)) /=
10539 Visible_Declarations
10540 (Specification (Unit_Declaration_Node (Current_Scope)))
10543 ("deferred constant must be declared in visible part",
10547 if Is_Access_Type (T)
10548 and then Nkind (Expression (N)) = N_Allocator
10550 Check_Recursive_Declaration (Designated_Type (T));
10553 end Constant_Redeclaration;
10555 ----------------------
10556 -- Constrain_Access --
10557 ----------------------
10559 procedure Constrain_Access
10560 (Def_Id : in out Entity_Id;
10562 Related_Nod : Node_Id)
10564 T : constant Entity_Id := Entity (Subtype_Mark (S));
10565 Desig_Type : constant Entity_Id := Designated_Type (T);
10566 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
10567 Constraint_OK : Boolean := True;
10569 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean;
10570 -- Simple predicate to test for defaulted discriminants
10571 -- Shouldn't this be in sem_util???
10573 ---------------------------------
10574 -- Has_Defaulted_Discriminants --
10575 ---------------------------------
10577 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean is
10579 return Has_Discriminants (Typ)
10580 and then Present (First_Discriminant (Typ))
10582 (Discriminant_Default_Value (First_Discriminant (Typ)));
10583 end Has_Defaulted_Discriminants;
10585 -- Start of processing for Constrain_Access
10588 if Is_Array_Type (Desig_Type) then
10589 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
10591 elsif (Is_Record_Type (Desig_Type)
10592 or else Is_Incomplete_Or_Private_Type (Desig_Type))
10593 and then not Is_Constrained (Desig_Type)
10595 -- ??? The following code is a temporary kludge to ignore a
10596 -- discriminant constraint on access type if it is constraining
10597 -- the current record. Avoid creating the implicit subtype of the
10598 -- record we are currently compiling since right now, we cannot
10599 -- handle these. For now, just return the access type itself.
10601 if Desig_Type = Current_Scope
10602 and then No (Def_Id)
10604 Set_Ekind (Desig_Subtype, E_Record_Subtype);
10605 Def_Id := Entity (Subtype_Mark (S));
10607 -- This call added to ensure that the constraint is analyzed
10608 -- (needed for a B test). Note that we still return early from
10609 -- this procedure to avoid recursive processing. ???
10611 Constrain_Discriminated_Type
10612 (Desig_Subtype, S, Related_Nod, For_Access => True);
10616 if (Ekind (T) = E_General_Access_Type
10617 or else Ada_Version >= Ada_2005)
10618 and then Has_Private_Declaration (Desig_Type)
10619 and then In_Open_Scopes (Scope (Desig_Type))
10620 and then Has_Discriminants (Desig_Type)
10622 -- Enforce rule that the constraint is illegal if there is
10623 -- an unconstrained view of the designated type. This means
10624 -- that the partial view (either a private type declaration or
10625 -- a derivation from a private type) has no discriminants.
10626 -- (Defect Report 8652/0008, Technical Corrigendum 1, checked
10627 -- by ACATS B371001).
10629 -- Rule updated for Ada 2005: the private type is said to have
10630 -- a constrained partial view, given that objects of the type
10631 -- can be declared. Furthermore, the rule applies to all access
10632 -- types, unlike the rule concerning default discriminants.
10635 Pack : constant Node_Id :=
10636 Unit_Declaration_Node (Scope (Desig_Type));
10641 if Nkind (Pack) = N_Package_Declaration then
10642 Decls := Visible_Declarations (Specification (Pack));
10643 Decl := First (Decls);
10644 while Present (Decl) loop
10645 if (Nkind (Decl) = N_Private_Type_Declaration
10647 Chars (Defining_Identifier (Decl)) =
10648 Chars (Desig_Type))
10651 (Nkind (Decl) = N_Full_Type_Declaration
10653 Chars (Defining_Identifier (Decl)) =
10655 and then Is_Derived_Type (Desig_Type)
10657 Has_Private_Declaration (Etype (Desig_Type)))
10659 if No (Discriminant_Specifications (Decl)) then
10661 ("cannot constrain general access type if " &
10662 "designated type has constrained partial view",
10675 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
10676 For_Access => True);
10678 elsif (Is_Task_Type (Desig_Type)
10679 or else Is_Protected_Type (Desig_Type))
10680 and then not Is_Constrained (Desig_Type)
10682 Constrain_Concurrent
10683 (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
10686 Error_Msg_N ("invalid constraint on access type", S);
10687 Desig_Subtype := Desig_Type; -- Ignore invalid constraint.
10688 Constraint_OK := False;
10691 if No (Def_Id) then
10692 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
10694 Set_Ekind (Def_Id, E_Access_Subtype);
10697 if Constraint_OK then
10698 Set_Etype (Def_Id, Base_Type (T));
10700 if Is_Private_Type (Desig_Type) then
10701 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
10704 Set_Etype (Def_Id, Any_Type);
10707 Set_Size_Info (Def_Id, T);
10708 Set_Is_Constrained (Def_Id, Constraint_OK);
10709 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
10710 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10711 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
10713 Conditional_Delay (Def_Id, T);
10715 -- AI-363 : Subtypes of general access types whose designated types have
10716 -- default discriminants are disallowed. In instances, the rule has to
10717 -- be checked against the actual, of which T is the subtype. In a
10718 -- generic body, the rule is checked assuming that the actual type has
10719 -- defaulted discriminants.
10721 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
10722 if Ekind (Base_Type (T)) = E_General_Access_Type
10723 and then Has_Defaulted_Discriminants (Desig_Type)
10725 if Ada_Version < Ada_2005 then
10727 ("access subtype of general access type would not " &
10728 "be allowed in Ada 2005?", S);
10731 ("access subtype of general access type not allowed", S);
10734 Error_Msg_N ("\discriminants have defaults", S);
10736 elsif Is_Access_Type (T)
10737 and then Is_Generic_Type (Desig_Type)
10738 and then Has_Discriminants (Desig_Type)
10739 and then In_Package_Body (Current_Scope)
10741 if Ada_Version < Ada_2005 then
10743 ("access subtype would not be allowed in generic body " &
10744 "in Ada 2005?", S);
10747 ("access subtype not allowed in generic body", S);
10751 ("\designated type is a discriminated formal", S);
10754 end Constrain_Access;
10756 ---------------------
10757 -- Constrain_Array --
10758 ---------------------
10760 procedure Constrain_Array
10761 (Def_Id : in out Entity_Id;
10763 Related_Nod : Node_Id;
10764 Related_Id : Entity_Id;
10765 Suffix : Character)
10767 C : constant Node_Id := Constraint (SI);
10768 Number_Of_Constraints : Nat := 0;
10771 Constraint_OK : Boolean := True;
10774 T := Entity (Subtype_Mark (SI));
10776 if Ekind (T) in Access_Kind then
10777 T := Designated_Type (T);
10780 -- If an index constraint follows a subtype mark in a subtype indication
10781 -- then the type or subtype denoted by the subtype mark must not already
10782 -- impose an index constraint. The subtype mark must denote either an
10783 -- unconstrained array type or an access type whose designated type
10784 -- is such an array type... (RM 3.6.1)
10786 if Is_Constrained (T) then
10787 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
10788 Constraint_OK := False;
10791 S := First (Constraints (C));
10792 while Present (S) loop
10793 Number_Of_Constraints := Number_Of_Constraints + 1;
10797 -- In either case, the index constraint must provide a discrete
10798 -- range for each index of the array type and the type of each
10799 -- discrete range must be the same as that of the corresponding
10800 -- index. (RM 3.6.1)
10802 if Number_Of_Constraints /= Number_Dimensions (T) then
10803 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
10804 Constraint_OK := False;
10807 S := First (Constraints (C));
10808 Index := First_Index (T);
10811 -- Apply constraints to each index type
10813 for J in 1 .. Number_Of_Constraints loop
10814 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
10822 if No (Def_Id) then
10824 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
10825 Set_Parent (Def_Id, Related_Nod);
10828 Set_Ekind (Def_Id, E_Array_Subtype);
10831 Set_Size_Info (Def_Id, (T));
10832 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10833 Set_Etype (Def_Id, Base_Type (T));
10835 if Constraint_OK then
10836 Set_First_Index (Def_Id, First (Constraints (C)));
10838 Set_First_Index (Def_Id, First_Index (T));
10841 Set_Is_Constrained (Def_Id, True);
10842 Set_Is_Aliased (Def_Id, Is_Aliased (T));
10843 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10845 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
10846 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
10848 -- A subtype does not inherit the packed_array_type of is parent. We
10849 -- need to initialize the attribute because if Def_Id is previously
10850 -- analyzed through a limited_with clause, it will have the attributes
10851 -- of an incomplete type, one of which is an Elist that overlaps the
10852 -- Packed_Array_Type field.
10854 Set_Packed_Array_Type (Def_Id, Empty);
10856 -- Build a freeze node if parent still needs one. Also make sure that
10857 -- the Depends_On_Private status is set because the subtype will need
10858 -- reprocessing at the time the base type does, and also we must set a
10859 -- conditional delay.
10861 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
10862 Conditional_Delay (Def_Id, T);
10863 end Constrain_Array;
10865 ------------------------------
10866 -- Constrain_Component_Type --
10867 ------------------------------
10869 function Constrain_Component_Type
10871 Constrained_Typ : Entity_Id;
10872 Related_Node : Node_Id;
10874 Constraints : Elist_Id) return Entity_Id
10876 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
10877 Compon_Type : constant Entity_Id := Etype (Comp);
10879 function Build_Constrained_Array_Type
10880 (Old_Type : Entity_Id) return Entity_Id;
10881 -- If Old_Type is an array type, one of whose indexes is constrained
10882 -- by a discriminant, build an Itype whose constraint replaces the
10883 -- discriminant with its value in the constraint.
10885 function Build_Constrained_Discriminated_Type
10886 (Old_Type : Entity_Id) return Entity_Id;
10887 -- Ditto for record components
10889 function Build_Constrained_Access_Type
10890 (Old_Type : Entity_Id) return Entity_Id;
10891 -- Ditto for access types. Makes use of previous two functions, to
10892 -- constrain designated type.
10894 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
10895 -- T is an array or discriminated type, C is a list of constraints
10896 -- that apply to T. This routine builds the constrained subtype.
10898 function Is_Discriminant (Expr : Node_Id) return Boolean;
10899 -- Returns True if Expr is a discriminant
10901 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
10902 -- Find the value of discriminant Discrim in Constraint
10904 -----------------------------------
10905 -- Build_Constrained_Access_Type --
10906 -----------------------------------
10908 function Build_Constrained_Access_Type
10909 (Old_Type : Entity_Id) return Entity_Id
10911 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
10913 Desig_Subtype : Entity_Id;
10917 -- if the original access type was not embedded in the enclosing
10918 -- type definition, there is no need to produce a new access
10919 -- subtype. In fact every access type with an explicit constraint
10920 -- generates an itype whose scope is the enclosing record.
10922 if not Is_Type (Scope (Old_Type)) then
10925 elsif Is_Array_Type (Desig_Type) then
10926 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
10928 elsif Has_Discriminants (Desig_Type) then
10930 -- This may be an access type to an enclosing record type for
10931 -- which we are constructing the constrained components. Return
10932 -- the enclosing record subtype. This is not always correct,
10933 -- but avoids infinite recursion. ???
10935 Desig_Subtype := Any_Type;
10937 for J in reverse 0 .. Scope_Stack.Last loop
10938 Scop := Scope_Stack.Table (J).Entity;
10941 and then Base_Type (Scop) = Base_Type (Desig_Type)
10943 Desig_Subtype := Scop;
10946 exit when not Is_Type (Scop);
10949 if Desig_Subtype = Any_Type then
10951 Build_Constrained_Discriminated_Type (Desig_Type);
10958 if Desig_Subtype /= Desig_Type then
10960 -- The Related_Node better be here or else we won't be able
10961 -- to attach new itypes to a node in the tree.
10963 pragma Assert (Present (Related_Node));
10965 Itype := Create_Itype (E_Access_Subtype, Related_Node);
10967 Set_Etype (Itype, Base_Type (Old_Type));
10968 Set_Size_Info (Itype, (Old_Type));
10969 Set_Directly_Designated_Type (Itype, Desig_Subtype);
10970 Set_Depends_On_Private (Itype, Has_Private_Component
10972 Set_Is_Access_Constant (Itype, Is_Access_Constant
10975 -- The new itype needs freezing when it depends on a not frozen
10976 -- type and the enclosing subtype needs freezing.
10978 if Has_Delayed_Freeze (Constrained_Typ)
10979 and then not Is_Frozen (Constrained_Typ)
10981 Conditional_Delay (Itype, Base_Type (Old_Type));
10989 end Build_Constrained_Access_Type;
10991 ----------------------------------
10992 -- Build_Constrained_Array_Type --
10993 ----------------------------------
10995 function Build_Constrained_Array_Type
10996 (Old_Type : Entity_Id) return Entity_Id
11000 Old_Index : Node_Id;
11001 Range_Node : Node_Id;
11002 Constr_List : List_Id;
11004 Need_To_Create_Itype : Boolean := False;
11007 Old_Index := First_Index (Old_Type);
11008 while Present (Old_Index) loop
11009 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
11011 if Is_Discriminant (Lo_Expr)
11012 or else Is_Discriminant (Hi_Expr)
11014 Need_To_Create_Itype := True;
11017 Next_Index (Old_Index);
11020 if Need_To_Create_Itype then
11021 Constr_List := New_List;
11023 Old_Index := First_Index (Old_Type);
11024 while Present (Old_Index) loop
11025 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
11027 if Is_Discriminant (Lo_Expr) then
11028 Lo_Expr := Get_Discr_Value (Lo_Expr);
11031 if Is_Discriminant (Hi_Expr) then
11032 Hi_Expr := Get_Discr_Value (Hi_Expr);
11037 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
11039 Append (Range_Node, To => Constr_List);
11041 Next_Index (Old_Index);
11044 return Build_Subtype (Old_Type, Constr_List);
11049 end Build_Constrained_Array_Type;
11051 ------------------------------------------
11052 -- Build_Constrained_Discriminated_Type --
11053 ------------------------------------------
11055 function Build_Constrained_Discriminated_Type
11056 (Old_Type : Entity_Id) return Entity_Id
11059 Constr_List : List_Id;
11060 Old_Constraint : Elmt_Id;
11062 Need_To_Create_Itype : Boolean := False;
11065 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
11066 while Present (Old_Constraint) loop
11067 Expr := Node (Old_Constraint);
11069 if Is_Discriminant (Expr) then
11070 Need_To_Create_Itype := True;
11073 Next_Elmt (Old_Constraint);
11076 if Need_To_Create_Itype then
11077 Constr_List := New_List;
11079 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
11080 while Present (Old_Constraint) loop
11081 Expr := Node (Old_Constraint);
11083 if Is_Discriminant (Expr) then
11084 Expr := Get_Discr_Value (Expr);
11087 Append (New_Copy_Tree (Expr), To => Constr_List);
11089 Next_Elmt (Old_Constraint);
11092 return Build_Subtype (Old_Type, Constr_List);
11097 end Build_Constrained_Discriminated_Type;
11099 -------------------
11100 -- Build_Subtype --
11101 -------------------
11103 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
11105 Subtyp_Decl : Node_Id;
11106 Def_Id : Entity_Id;
11107 Btyp : Entity_Id := Base_Type (T);
11110 -- The Related_Node better be here or else we won't be able to
11111 -- attach new itypes to a node in the tree.
11113 pragma Assert (Present (Related_Node));
11115 -- If the view of the component's type is incomplete or private
11116 -- with unknown discriminants, then the constraint must be applied
11117 -- to the full type.
11119 if Has_Unknown_Discriminants (Btyp)
11120 and then Present (Underlying_Type (Btyp))
11122 Btyp := Underlying_Type (Btyp);
11126 Make_Subtype_Indication (Loc,
11127 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
11128 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
11130 Def_Id := Create_Itype (Ekind (T), Related_Node);
11133 Make_Subtype_Declaration (Loc,
11134 Defining_Identifier => Def_Id,
11135 Subtype_Indication => Indic);
11137 Set_Parent (Subtyp_Decl, Parent (Related_Node));
11139 -- Itypes must be analyzed with checks off (see package Itypes)
11141 Analyze (Subtyp_Decl, Suppress => All_Checks);
11146 ---------------------
11147 -- Get_Discr_Value --
11148 ---------------------
11150 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
11155 -- The discriminant may be declared for the type, in which case we
11156 -- find it by iterating over the list of discriminants. If the
11157 -- discriminant is inherited from a parent type, it appears as the
11158 -- corresponding discriminant of the current type. This will be the
11159 -- case when constraining an inherited component whose constraint is
11160 -- given by a discriminant of the parent.
11162 D := First_Discriminant (Typ);
11163 E := First_Elmt (Constraints);
11165 while Present (D) loop
11166 if D = Entity (Discrim)
11167 or else D = CR_Discriminant (Entity (Discrim))
11168 or else Corresponding_Discriminant (D) = Entity (Discrim)
11173 Next_Discriminant (D);
11177 -- The Corresponding_Discriminant mechanism is incomplete, because
11178 -- the correspondence between new and old discriminants is not one
11179 -- to one: one new discriminant can constrain several old ones. In
11180 -- that case, scan sequentially the stored_constraint, the list of
11181 -- discriminants of the parents, and the constraints.
11182 -- Previous code checked for the present of the Stored_Constraint
11183 -- list for the derived type, but did not use it at all. Should it
11184 -- be present when the component is a discriminated task type?
11186 if Is_Derived_Type (Typ)
11187 and then Scope (Entity (Discrim)) = Etype (Typ)
11189 D := First_Discriminant (Etype (Typ));
11190 E := First_Elmt (Constraints);
11191 while Present (D) loop
11192 if D = Entity (Discrim) then
11196 Next_Discriminant (D);
11201 -- Something is wrong if we did not find the value
11203 raise Program_Error;
11204 end Get_Discr_Value;
11206 ---------------------
11207 -- Is_Discriminant --
11208 ---------------------
11210 function Is_Discriminant (Expr : Node_Id) return Boolean is
11211 Discrim_Scope : Entity_Id;
11214 if Denotes_Discriminant (Expr) then
11215 Discrim_Scope := Scope (Entity (Expr));
11217 -- Either we have a reference to one of Typ's discriminants,
11219 pragma Assert (Discrim_Scope = Typ
11221 -- or to the discriminants of the parent type, in the case
11222 -- of a derivation of a tagged type with variants.
11224 or else Discrim_Scope = Etype (Typ)
11225 or else Full_View (Discrim_Scope) = Etype (Typ)
11227 -- or same as above for the case where the discriminants
11228 -- were declared in Typ's private view.
11230 or else (Is_Private_Type (Discrim_Scope)
11231 and then Chars (Discrim_Scope) = Chars (Typ))
11233 -- or else we are deriving from the full view and the
11234 -- discriminant is declared in the private entity.
11236 or else (Is_Private_Type (Typ)
11237 and then Chars (Discrim_Scope) = Chars (Typ))
11239 -- Or we are constrained the corresponding record of a
11240 -- synchronized type that completes a private declaration.
11242 or else (Is_Concurrent_Record_Type (Typ)
11244 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
11246 -- or we have a class-wide type, in which case make sure the
11247 -- discriminant found belongs to the root type.
11249 or else (Is_Class_Wide_Type (Typ)
11250 and then Etype (Typ) = Discrim_Scope));
11255 -- In all other cases we have something wrong
11258 end Is_Discriminant;
11260 -- Start of processing for Constrain_Component_Type
11263 if Nkind (Parent (Comp)) = N_Component_Declaration
11264 and then Comes_From_Source (Parent (Comp))
11265 and then Comes_From_Source
11266 (Subtype_Indication (Component_Definition (Parent (Comp))))
11269 (Subtype_Indication (Component_Definition (Parent (Comp))))
11271 return Compon_Type;
11273 elsif Is_Array_Type (Compon_Type) then
11274 return Build_Constrained_Array_Type (Compon_Type);
11276 elsif Has_Discriminants (Compon_Type) then
11277 return Build_Constrained_Discriminated_Type (Compon_Type);
11279 elsif Is_Access_Type (Compon_Type) then
11280 return Build_Constrained_Access_Type (Compon_Type);
11283 return Compon_Type;
11285 end Constrain_Component_Type;
11287 --------------------------
11288 -- Constrain_Concurrent --
11289 --------------------------
11291 -- For concurrent types, the associated record value type carries the same
11292 -- discriminants, so when we constrain a concurrent type, we must constrain
11293 -- the corresponding record type as well.
11295 procedure Constrain_Concurrent
11296 (Def_Id : in out Entity_Id;
11298 Related_Nod : Node_Id;
11299 Related_Id : Entity_Id;
11300 Suffix : Character)
11302 T_Ent : Entity_Id := Entity (Subtype_Mark (SI));
11306 if Ekind (T_Ent) in Access_Kind then
11307 T_Ent := Designated_Type (T_Ent);
11310 T_Val := Corresponding_Record_Type (T_Ent);
11312 if Present (T_Val) then
11314 if No (Def_Id) then
11315 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
11318 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
11320 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
11321 Set_Corresponding_Record_Type (Def_Id,
11322 Constrain_Corresponding_Record
11323 (Def_Id, T_Val, Related_Nod, Related_Id));
11326 -- If there is no associated record, expansion is disabled and this
11327 -- is a generic context. Create a subtype in any case, so that
11328 -- semantic analysis can proceed.
11330 if No (Def_Id) then
11331 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
11334 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
11336 end Constrain_Concurrent;
11338 ------------------------------------
11339 -- Constrain_Corresponding_Record --
11340 ------------------------------------
11342 function Constrain_Corresponding_Record
11343 (Prot_Subt : Entity_Id;
11344 Corr_Rec : Entity_Id;
11345 Related_Nod : Node_Id;
11346 Related_Id : Entity_Id) return Entity_Id
11348 T_Sub : constant Entity_Id :=
11349 Create_Itype (E_Record_Subtype, Related_Nod, Related_Id, 'V');
11352 Set_Etype (T_Sub, Corr_Rec);
11353 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
11354 Set_Is_Constrained (T_Sub, True);
11355 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
11356 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
11358 -- As elsewhere, we do not want to create a freeze node for this itype
11359 -- if it is created for a constrained component of an enclosing record
11360 -- because references to outer discriminants will appear out of scope.
11362 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
11363 Conditional_Delay (T_Sub, Corr_Rec);
11365 Set_Is_Frozen (T_Sub);
11368 if Has_Discriminants (Prot_Subt) then -- False only if errors.
11369 Set_Discriminant_Constraint
11370 (T_Sub, Discriminant_Constraint (Prot_Subt));
11371 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
11372 Create_Constrained_Components
11373 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
11376 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
11379 end Constrain_Corresponding_Record;
11381 -----------------------
11382 -- Constrain_Decimal --
11383 -----------------------
11385 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
11386 T : constant Entity_Id := Entity (Subtype_Mark (S));
11387 C : constant Node_Id := Constraint (S);
11388 Loc : constant Source_Ptr := Sloc (C);
11389 Range_Expr : Node_Id;
11390 Digits_Expr : Node_Id;
11395 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
11397 if Nkind (C) = N_Range_Constraint then
11398 Range_Expr := Range_Expression (C);
11399 Digits_Val := Digits_Value (T);
11402 pragma Assert (Nkind (C) = N_Digits_Constraint);
11404 Check_SPARK_Restriction ("digits constraint is not allowed", S);
11406 Digits_Expr := Digits_Expression (C);
11407 Analyze_And_Resolve (Digits_Expr, Any_Integer);
11409 Check_Digits_Expression (Digits_Expr);
11410 Digits_Val := Expr_Value (Digits_Expr);
11412 if Digits_Val > Digits_Value (T) then
11414 ("digits expression is incompatible with subtype", C);
11415 Digits_Val := Digits_Value (T);
11418 if Present (Range_Constraint (C)) then
11419 Range_Expr := Range_Expression (Range_Constraint (C));
11421 Range_Expr := Empty;
11425 Set_Etype (Def_Id, Base_Type (T));
11426 Set_Size_Info (Def_Id, (T));
11427 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11428 Set_Delta_Value (Def_Id, Delta_Value (T));
11429 Set_Scale_Value (Def_Id, Scale_Value (T));
11430 Set_Small_Value (Def_Id, Small_Value (T));
11431 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
11432 Set_Digits_Value (Def_Id, Digits_Val);
11434 -- Manufacture range from given digits value if no range present
11436 if No (Range_Expr) then
11437 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
11441 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
11443 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
11446 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
11447 Set_Discrete_RM_Size (Def_Id);
11449 -- Unconditionally delay the freeze, since we cannot set size
11450 -- information in all cases correctly until the freeze point.
11452 Set_Has_Delayed_Freeze (Def_Id);
11453 end Constrain_Decimal;
11455 ----------------------------------
11456 -- Constrain_Discriminated_Type --
11457 ----------------------------------
11459 procedure Constrain_Discriminated_Type
11460 (Def_Id : Entity_Id;
11462 Related_Nod : Node_Id;
11463 For_Access : Boolean := False)
11465 E : constant Entity_Id := Entity (Subtype_Mark (S));
11468 Elist : Elist_Id := New_Elmt_List;
11470 procedure Fixup_Bad_Constraint;
11471 -- This is called after finding a bad constraint, and after having
11472 -- posted an appropriate error message. The mission is to leave the
11473 -- entity T in as reasonable state as possible!
11475 --------------------------
11476 -- Fixup_Bad_Constraint --
11477 --------------------------
11479 procedure Fixup_Bad_Constraint is
11481 -- Set a reasonable Ekind for the entity. For an incomplete type,
11482 -- we can't do much, but for other types, we can set the proper
11483 -- corresponding subtype kind.
11485 if Ekind (T) = E_Incomplete_Type then
11486 Set_Ekind (Def_Id, Ekind (T));
11488 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
11491 -- Set Etype to the known type, to reduce chances of cascaded errors
11493 Set_Etype (Def_Id, E);
11494 Set_Error_Posted (Def_Id);
11495 end Fixup_Bad_Constraint;
11497 -- Start of processing for Constrain_Discriminated_Type
11500 C := Constraint (S);
11502 -- A discriminant constraint is only allowed in a subtype indication,
11503 -- after a subtype mark. This subtype mark must denote either a type
11504 -- with discriminants, or an access type whose designated type is a
11505 -- type with discriminants. A discriminant constraint specifies the
11506 -- values of these discriminants (RM 3.7.2(5)).
11508 T := Base_Type (Entity (Subtype_Mark (S)));
11510 if Ekind (T) in Access_Kind then
11511 T := Designated_Type (T);
11514 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
11515 -- Avoid generating an error for access-to-incomplete subtypes.
11517 if Ada_Version >= Ada_2005
11518 and then Ekind (T) = E_Incomplete_Type
11519 and then Nkind (Parent (S)) = N_Subtype_Declaration
11520 and then not Is_Itype (Def_Id)
11522 -- A little sanity check, emit an error message if the type
11523 -- has discriminants to begin with. Type T may be a regular
11524 -- incomplete type or imported via a limited with clause.
11526 if Has_Discriminants (T)
11528 (From_With_Type (T)
11529 and then Present (Non_Limited_View (T))
11530 and then Nkind (Parent (Non_Limited_View (T))) =
11531 N_Full_Type_Declaration
11532 and then Present (Discriminant_Specifications
11533 (Parent (Non_Limited_View (T)))))
11536 ("(Ada 2005) incomplete subtype may not be constrained", C);
11538 Error_Msg_N ("invalid constraint: type has no discriminant", C);
11541 Fixup_Bad_Constraint;
11544 -- Check that the type has visible discriminants. The type may be
11545 -- a private type with unknown discriminants whose full view has
11546 -- discriminants which are invisible.
11548 elsif not Has_Discriminants (T)
11550 (Has_Unknown_Discriminants (T)
11551 and then Is_Private_Type (T))
11553 Error_Msg_N ("invalid constraint: type has no discriminant", C);
11554 Fixup_Bad_Constraint;
11557 elsif Is_Constrained (E)
11558 or else (Ekind (E) = E_Class_Wide_Subtype
11559 and then Present (Discriminant_Constraint (E)))
11561 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
11562 Fixup_Bad_Constraint;
11566 -- T may be an unconstrained subtype (e.g. a generic actual).
11567 -- Constraint applies to the base type.
11569 T := Base_Type (T);
11571 Elist := Build_Discriminant_Constraints (T, S);
11573 -- If the list returned was empty we had an error in building the
11574 -- discriminant constraint. We have also already signalled an error
11575 -- in the incomplete type case
11577 if Is_Empty_Elmt_List (Elist) then
11578 Fixup_Bad_Constraint;
11582 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
11583 end Constrain_Discriminated_Type;
11585 ---------------------------
11586 -- Constrain_Enumeration --
11587 ---------------------------
11589 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
11590 T : constant Entity_Id := Entity (Subtype_Mark (S));
11591 C : constant Node_Id := Constraint (S);
11594 -- By default, consider that the enumeration subtype is in ALFA if the
11595 -- entity of its subtype mark is in ALFA. This is reversed later if the
11596 -- range of the subtype is not static.
11598 if Nkind (Original_Node (Parent (Def_Id))) = N_Subtype_Declaration
11599 and then Is_In_ALFA (T)
11601 Set_Is_In_ALFA (Def_Id);
11604 Set_Ekind (Def_Id, E_Enumeration_Subtype);
11606 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
11608 Set_Etype (Def_Id, Base_Type (T));
11609 Set_Size_Info (Def_Id, (T));
11610 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11611 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
11613 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11615 Set_Discrete_RM_Size (Def_Id);
11616 end Constrain_Enumeration;
11618 ----------------------
11619 -- Constrain_Float --
11620 ----------------------
11622 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
11623 T : constant Entity_Id := Entity (Subtype_Mark (S));
11629 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
11631 Set_Etype (Def_Id, Base_Type (T));
11632 Set_Size_Info (Def_Id, (T));
11633 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11635 -- Process the constraint
11637 C := Constraint (S);
11639 -- Digits constraint present
11641 if Nkind (C) = N_Digits_Constraint then
11643 Check_SPARK_Restriction ("digits constraint is not allowed", S);
11644 Check_Restriction (No_Obsolescent_Features, C);
11646 if Warn_On_Obsolescent_Feature then
11648 ("subtype digits constraint is an " &
11649 "obsolescent feature (RM J.3(8))?", C);
11652 D := Digits_Expression (C);
11653 Analyze_And_Resolve (D, Any_Integer);
11654 Check_Digits_Expression (D);
11655 Set_Digits_Value (Def_Id, Expr_Value (D));
11657 -- Check that digits value is in range. Obviously we can do this
11658 -- at compile time, but it is strictly a runtime check, and of
11659 -- course there is an ACVC test that checks this!
11661 if Digits_Value (Def_Id) > Digits_Value (T) then
11662 Error_Msg_Uint_1 := Digits_Value (T);
11663 Error_Msg_N ("?digits value is too large, maximum is ^", D);
11665 Make_Raise_Constraint_Error (Sloc (D),
11666 Reason => CE_Range_Check_Failed);
11667 Insert_Action (Declaration_Node (Def_Id), Rais);
11670 C := Range_Constraint (C);
11672 -- No digits constraint present
11675 Set_Digits_Value (Def_Id, Digits_Value (T));
11678 -- Range constraint present
11680 if Nkind (C) = N_Range_Constraint then
11681 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11683 -- No range constraint present
11686 pragma Assert (No (C));
11687 Set_Scalar_Range (Def_Id, Scalar_Range (T));
11690 Set_Is_Constrained (Def_Id);
11691 end Constrain_Float;
11693 ---------------------
11694 -- Constrain_Index --
11695 ---------------------
11697 procedure Constrain_Index
11700 Related_Nod : Node_Id;
11701 Related_Id : Entity_Id;
11702 Suffix : Character;
11703 Suffix_Index : Nat)
11705 Def_Id : Entity_Id;
11706 R : Node_Id := Empty;
11707 T : constant Entity_Id := Etype (Index);
11710 if Nkind (S) = N_Range
11712 (Nkind (S) = N_Attribute_Reference
11713 and then Attribute_Name (S) = Name_Range)
11715 -- A Range attribute will be transformed into N_Range by Resolve
11721 Process_Range_Expr_In_Decl (R, T, Empty_List);
11723 if not Error_Posted (S)
11725 (Nkind (S) /= N_Range
11726 or else not Covers (T, (Etype (Low_Bound (S))))
11727 or else not Covers (T, (Etype (High_Bound (S)))))
11729 if Base_Type (T) /= Any_Type
11730 and then Etype (Low_Bound (S)) /= Any_Type
11731 and then Etype (High_Bound (S)) /= Any_Type
11733 Error_Msg_N ("range expected", S);
11737 elsif Nkind (S) = N_Subtype_Indication then
11739 -- The parser has verified that this is a discrete indication
11741 Resolve_Discrete_Subtype_Indication (S, T);
11742 R := Range_Expression (Constraint (S));
11744 -- Capture values of bounds and generate temporaries for them if
11745 -- needed, since checks may cause duplication of the expressions
11746 -- which must not be reevaluated.
11748 if Expander_Active then
11749 Force_Evaluation (Low_Bound (R));
11750 Force_Evaluation (High_Bound (R));
11753 elsif Nkind (S) = N_Discriminant_Association then
11755 -- Syntactically valid in subtype indication
11757 Error_Msg_N ("invalid index constraint", S);
11758 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11761 -- Subtype_Mark case, no anonymous subtypes to construct
11766 if Is_Entity_Name (S) then
11767 if not Is_Type (Entity (S)) then
11768 Error_Msg_N ("expect subtype mark for index constraint", S);
11770 elsif Base_Type (Entity (S)) /= Base_Type (T) then
11771 Wrong_Type (S, Base_Type (T));
11773 -- Check error of subtype with predicate in index constraint
11776 Bad_Predicated_Subtype_Use
11777 ("subtype& has predicate, not allowed in index constraint",
11784 Error_Msg_N ("invalid index constraint", S);
11785 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11791 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
11793 Set_Etype (Def_Id, Base_Type (T));
11795 if Is_Modular_Integer_Type (T) then
11796 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11798 elsif Is_Integer_Type (T) then
11799 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11802 Set_Ekind (Def_Id, E_Enumeration_Subtype);
11803 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
11804 Set_First_Literal (Def_Id, First_Literal (T));
11807 Set_Size_Info (Def_Id, (T));
11808 Set_RM_Size (Def_Id, RM_Size (T));
11809 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11811 Set_Scalar_Range (Def_Id, R);
11813 Set_Etype (S, Def_Id);
11814 Set_Discrete_RM_Size (Def_Id);
11815 end Constrain_Index;
11817 -----------------------
11818 -- Constrain_Integer --
11819 -----------------------
11821 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
11822 T : constant Entity_Id := Entity (Subtype_Mark (S));
11823 C : constant Node_Id := Constraint (S);
11826 -- By default, consider that the integer subtype is in ALFA if the
11827 -- entity of its subtype mark is in ALFA. This is reversed later if the
11828 -- range of the subtype is not static.
11830 if Nkind (Original_Node (Parent (Def_Id))) = N_Subtype_Declaration
11831 and then Is_In_ALFA (T)
11833 Set_Is_In_ALFA (Def_Id);
11836 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11838 if Is_Modular_Integer_Type (T) then
11839 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11841 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11844 Set_Etype (Def_Id, Base_Type (T));
11845 Set_Size_Info (Def_Id, (T));
11846 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11847 Set_Discrete_RM_Size (Def_Id);
11848 end Constrain_Integer;
11850 ------------------------------
11851 -- Constrain_Ordinary_Fixed --
11852 ------------------------------
11854 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
11855 T : constant Entity_Id := Entity (Subtype_Mark (S));
11861 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
11862 Set_Etype (Def_Id, Base_Type (T));
11863 Set_Size_Info (Def_Id, (T));
11864 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11865 Set_Small_Value (Def_Id, Small_Value (T));
11867 -- Process the constraint
11869 C := Constraint (S);
11871 -- Delta constraint present
11873 if Nkind (C) = N_Delta_Constraint then
11875 Check_SPARK_Restriction ("delta constraint is not allowed", S);
11876 Check_Restriction (No_Obsolescent_Features, C);
11878 if Warn_On_Obsolescent_Feature then
11880 ("subtype delta constraint is an " &
11881 "obsolescent feature (RM J.3(7))?");
11884 D := Delta_Expression (C);
11885 Analyze_And_Resolve (D, Any_Real);
11886 Check_Delta_Expression (D);
11887 Set_Delta_Value (Def_Id, Expr_Value_R (D));
11889 -- Check that delta value is in range. Obviously we can do this
11890 -- at compile time, but it is strictly a runtime check, and of
11891 -- course there is an ACVC test that checks this!
11893 if Delta_Value (Def_Id) < Delta_Value (T) then
11894 Error_Msg_N ("?delta value is too small", D);
11896 Make_Raise_Constraint_Error (Sloc (D),
11897 Reason => CE_Range_Check_Failed);
11898 Insert_Action (Declaration_Node (Def_Id), Rais);
11901 C := Range_Constraint (C);
11903 -- No delta constraint present
11906 Set_Delta_Value (Def_Id, Delta_Value (T));
11909 -- Range constraint present
11911 if Nkind (C) = N_Range_Constraint then
11912 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11914 -- No range constraint present
11917 pragma Assert (No (C));
11918 Set_Scalar_Range (Def_Id, Scalar_Range (T));
11922 Set_Discrete_RM_Size (Def_Id);
11924 -- Unconditionally delay the freeze, since we cannot set size
11925 -- information in all cases correctly until the freeze point.
11927 Set_Has_Delayed_Freeze (Def_Id);
11928 end Constrain_Ordinary_Fixed;
11930 -----------------------
11931 -- Contain_Interface --
11932 -----------------------
11934 function Contain_Interface
11935 (Iface : Entity_Id;
11936 Ifaces : Elist_Id) return Boolean
11938 Iface_Elmt : Elmt_Id;
11941 if Present (Ifaces) then
11942 Iface_Elmt := First_Elmt (Ifaces);
11943 while Present (Iface_Elmt) loop
11944 if Node (Iface_Elmt) = Iface then
11948 Next_Elmt (Iface_Elmt);
11953 end Contain_Interface;
11955 ---------------------------
11956 -- Convert_Scalar_Bounds --
11957 ---------------------------
11959 procedure Convert_Scalar_Bounds
11961 Parent_Type : Entity_Id;
11962 Derived_Type : Entity_Id;
11965 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
11972 -- Defend against previous errors
11974 if No (Scalar_Range (Derived_Type)) then
11978 Lo := Build_Scalar_Bound
11979 (Type_Low_Bound (Derived_Type),
11980 Parent_Type, Implicit_Base);
11982 Hi := Build_Scalar_Bound
11983 (Type_High_Bound (Derived_Type),
11984 Parent_Type, Implicit_Base);
11991 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
11993 Set_Parent (Rng, N);
11994 Set_Scalar_Range (Derived_Type, Rng);
11996 -- Analyze the bounds
11998 Analyze_And_Resolve (Lo, Implicit_Base);
11999 Analyze_And_Resolve (Hi, Implicit_Base);
12001 -- Analyze the range itself, except that we do not analyze it if
12002 -- the bounds are real literals, and we have a fixed-point type.
12003 -- The reason for this is that we delay setting the bounds in this
12004 -- case till we know the final Small and Size values (see circuit
12005 -- in Freeze.Freeze_Fixed_Point_Type for further details).
12007 if Is_Fixed_Point_Type (Parent_Type)
12008 and then Nkind (Lo) = N_Real_Literal
12009 and then Nkind (Hi) = N_Real_Literal
12013 -- Here we do the analysis of the range
12015 -- Note: we do this manually, since if we do a normal Analyze and
12016 -- Resolve call, there are problems with the conversions used for
12017 -- the derived type range.
12020 Set_Etype (Rng, Implicit_Base);
12021 Set_Analyzed (Rng, True);
12023 end Convert_Scalar_Bounds;
12025 -------------------
12026 -- Copy_And_Swap --
12027 -------------------
12029 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
12031 -- Initialize new full declaration entity by copying the pertinent
12032 -- fields of the corresponding private declaration entity.
12034 -- We temporarily set Ekind to a value appropriate for a type to
12035 -- avoid assert failures in Einfo from checking for setting type
12036 -- attributes on something that is not a type. Ekind (Priv) is an
12037 -- appropriate choice, since it allowed the attributes to be set
12038 -- in the first place. This Ekind value will be modified later.
12040 Set_Ekind (Full, Ekind (Priv));
12042 -- Also set Etype temporarily to Any_Type, again, in the absence
12043 -- of errors, it will be properly reset, and if there are errors,
12044 -- then we want a value of Any_Type to remain.
12046 Set_Etype (Full, Any_Type);
12048 -- Now start copying attributes
12050 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
12052 if Has_Discriminants (Full) then
12053 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
12054 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
12057 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
12058 Set_Homonym (Full, Homonym (Priv));
12059 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
12060 Set_Is_Public (Full, Is_Public (Priv));
12061 Set_Is_Pure (Full, Is_Pure (Priv));
12062 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
12063 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
12064 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
12065 Set_Has_Pragma_Unreferenced_Objects
12066 (Full, Has_Pragma_Unreferenced_Objects
12069 Conditional_Delay (Full, Priv);
12071 if Is_Tagged_Type (Full) then
12072 Set_Direct_Primitive_Operations (Full,
12073 Direct_Primitive_Operations (Priv));
12075 if Is_Base_Type (Priv) then
12076 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
12080 Set_Is_Volatile (Full, Is_Volatile (Priv));
12081 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
12082 Set_Scope (Full, Scope (Priv));
12083 Set_Next_Entity (Full, Next_Entity (Priv));
12084 Set_First_Entity (Full, First_Entity (Priv));
12085 Set_Last_Entity (Full, Last_Entity (Priv));
12087 -- If access types have been recorded for later handling, keep them in
12088 -- the full view so that they get handled when the full view freeze
12089 -- node is expanded.
12091 if Present (Freeze_Node (Priv))
12092 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
12094 Ensure_Freeze_Node (Full);
12095 Set_Access_Types_To_Process
12096 (Freeze_Node (Full),
12097 Access_Types_To_Process (Freeze_Node (Priv)));
12100 -- Swap the two entities. Now Private is the full type entity and Full
12101 -- is the private one. They will be swapped back at the end of the
12102 -- private part. This swapping ensures that the entity that is visible
12103 -- in the private part is the full declaration.
12105 Exchange_Entities (Priv, Full);
12106 Append_Entity (Full, Scope (Full));
12109 -------------------------------------
12110 -- Copy_Array_Base_Type_Attributes --
12111 -------------------------------------
12113 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
12115 Set_Component_Alignment (T1, Component_Alignment (T2));
12116 Set_Component_Type (T1, Component_Type (T2));
12117 Set_Component_Size (T1, Component_Size (T2));
12118 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
12119 Set_Finalize_Storage_Only (T1, Finalize_Storage_Only (T2));
12120 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
12121 Set_Has_Task (T1, Has_Task (T2));
12122 Set_Is_Packed (T1, Is_Packed (T2));
12123 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
12124 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
12125 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
12126 end Copy_Array_Base_Type_Attributes;
12128 -----------------------------------
12129 -- Copy_Array_Subtype_Attributes --
12130 -----------------------------------
12132 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
12134 Set_Size_Info (T1, T2);
12136 Set_First_Index (T1, First_Index (T2));
12137 Set_Is_Aliased (T1, Is_Aliased (T2));
12138 Set_Is_Atomic (T1, Is_Atomic (T2));
12139 Set_Is_Volatile (T1, Is_Volatile (T2));
12140 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
12141 Set_Is_Constrained (T1, Is_Constrained (T2));
12142 Set_Depends_On_Private (T1, Has_Private_Component (T2));
12143 Set_First_Rep_Item (T1, First_Rep_Item (T2));
12144 Set_Convention (T1, Convention (T2));
12145 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
12146 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
12147 Set_Packed_Array_Type (T1, Packed_Array_Type (T2));
12148 end Copy_Array_Subtype_Attributes;
12150 -----------------------------------
12151 -- Create_Constrained_Components --
12152 -----------------------------------
12154 procedure Create_Constrained_Components
12156 Decl_Node : Node_Id;
12158 Constraints : Elist_Id)
12160 Loc : constant Source_Ptr := Sloc (Subt);
12161 Comp_List : constant Elist_Id := New_Elmt_List;
12162 Parent_Type : constant Entity_Id := Etype (Typ);
12163 Assoc_List : constant List_Id := New_List;
12164 Discr_Val : Elmt_Id;
12168 Is_Static : Boolean := True;
12170 procedure Collect_Fixed_Components (Typ : Entity_Id);
12171 -- Collect parent type components that do not appear in a variant part
12173 procedure Create_All_Components;
12174 -- Iterate over Comp_List to create the components of the subtype
12176 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
12177 -- Creates a new component from Old_Compon, copying all the fields from
12178 -- it, including its Etype, inserts the new component in the Subt entity
12179 -- chain and returns the new component.
12181 function Is_Variant_Record (T : Entity_Id) return Boolean;
12182 -- If true, and discriminants are static, collect only components from
12183 -- variants selected by discriminant values.
12185 ------------------------------
12186 -- Collect_Fixed_Components --
12187 ------------------------------
12189 procedure Collect_Fixed_Components (Typ : Entity_Id) is
12191 -- Build association list for discriminants, and find components of the
12192 -- variant part selected by the values of the discriminants.
12194 Old_C := First_Discriminant (Typ);
12195 Discr_Val := First_Elmt (Constraints);
12196 while Present (Old_C) loop
12197 Append_To (Assoc_List,
12198 Make_Component_Association (Loc,
12199 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
12200 Expression => New_Copy (Node (Discr_Val))));
12202 Next_Elmt (Discr_Val);
12203 Next_Discriminant (Old_C);
12206 -- The tag and the possible parent component are unconditionally in
12209 if Is_Tagged_Type (Typ)
12210 or else Has_Controlled_Component (Typ)
12212 Old_C := First_Component (Typ);
12213 while Present (Old_C) loop
12214 if Chars ((Old_C)) = Name_uTag
12215 or else Chars ((Old_C)) = Name_uParent
12217 Append_Elmt (Old_C, Comp_List);
12220 Next_Component (Old_C);
12223 end Collect_Fixed_Components;
12225 ---------------------------
12226 -- Create_All_Components --
12227 ---------------------------
12229 procedure Create_All_Components is
12233 Comp := First_Elmt (Comp_List);
12234 while Present (Comp) loop
12235 Old_C := Node (Comp);
12236 New_C := Create_Component (Old_C);
12240 Constrain_Component_Type
12241 (Old_C, Subt, Decl_Node, Typ, Constraints));
12242 Set_Is_Public (New_C, Is_Public (Subt));
12246 end Create_All_Components;
12248 ----------------------
12249 -- Create_Component --
12250 ----------------------
12252 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
12253 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
12256 if Ekind (Old_Compon) = E_Discriminant
12257 and then Is_Completely_Hidden (Old_Compon)
12259 -- This is a shadow discriminant created for a discriminant of
12260 -- the parent type, which needs to be present in the subtype.
12261 -- Give the shadow discriminant an internal name that cannot
12262 -- conflict with that of visible components.
12264 Set_Chars (New_Compon, New_Internal_Name ('C'));
12267 -- Set the parent so we have a proper link for freezing etc. This is
12268 -- not a real parent pointer, since of course our parent does not own
12269 -- up to us and reference us, we are an illegitimate child of the
12270 -- original parent!
12272 Set_Parent (New_Compon, Parent (Old_Compon));
12274 -- If the old component's Esize was already determined and is a
12275 -- static value, then the new component simply inherits it. Otherwise
12276 -- the old component's size may require run-time determination, but
12277 -- the new component's size still might be statically determinable
12278 -- (if, for example it has a static constraint). In that case we want
12279 -- Layout_Type to recompute the component's size, so we reset its
12280 -- size and positional fields.
12282 if Frontend_Layout_On_Target
12283 and then not Known_Static_Esize (Old_Compon)
12285 Set_Esize (New_Compon, Uint_0);
12286 Init_Normalized_First_Bit (New_Compon);
12287 Init_Normalized_Position (New_Compon);
12288 Init_Normalized_Position_Max (New_Compon);
12291 -- We do not want this node marked as Comes_From_Source, since
12292 -- otherwise it would get first class status and a separate cross-
12293 -- reference line would be generated. Illegitimate children do not
12294 -- rate such recognition.
12296 Set_Comes_From_Source (New_Compon, False);
12298 -- But it is a real entity, and a birth certificate must be properly
12299 -- registered by entering it into the entity list.
12301 Enter_Name (New_Compon);
12304 end Create_Component;
12306 -----------------------
12307 -- Is_Variant_Record --
12308 -----------------------
12310 function Is_Variant_Record (T : Entity_Id) return Boolean is
12312 return Nkind (Parent (T)) = N_Full_Type_Declaration
12313 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
12314 and then Present (Component_List (Type_Definition (Parent (T))))
12317 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
12318 end Is_Variant_Record;
12320 -- Start of processing for Create_Constrained_Components
12323 pragma Assert (Subt /= Base_Type (Subt));
12324 pragma Assert (Typ = Base_Type (Typ));
12326 Set_First_Entity (Subt, Empty);
12327 Set_Last_Entity (Subt, Empty);
12329 -- Check whether constraint is fully static, in which case we can
12330 -- optimize the list of components.
12332 Discr_Val := First_Elmt (Constraints);
12333 while Present (Discr_Val) loop
12334 if not Is_OK_Static_Expression (Node (Discr_Val)) then
12335 Is_Static := False;
12339 Next_Elmt (Discr_Val);
12342 Set_Has_Static_Discriminants (Subt, Is_Static);
12346 -- Inherit the discriminants of the parent type
12348 Add_Discriminants : declare
12354 Old_C := First_Discriminant (Typ);
12356 while Present (Old_C) loop
12357 Num_Disc := Num_Disc + 1;
12358 New_C := Create_Component (Old_C);
12359 Set_Is_Public (New_C, Is_Public (Subt));
12360 Next_Discriminant (Old_C);
12363 -- For an untagged derived subtype, the number of discriminants may
12364 -- be smaller than the number of inherited discriminants, because
12365 -- several of them may be renamed by a single new discriminant or
12366 -- constrained. In this case, add the hidden discriminants back into
12367 -- the subtype, because they need to be present if the optimizer of
12368 -- the GCC 4.x back-end decides to break apart assignments between
12369 -- objects using the parent view into member-wise assignments.
12373 if Is_Derived_Type (Typ)
12374 and then not Is_Tagged_Type (Typ)
12376 Old_C := First_Stored_Discriminant (Typ);
12378 while Present (Old_C) loop
12379 Num_Gird := Num_Gird + 1;
12380 Next_Stored_Discriminant (Old_C);
12384 if Num_Gird > Num_Disc then
12386 -- Find out multiple uses of new discriminants, and add hidden
12387 -- components for the extra renamed discriminants. We recognize
12388 -- multiple uses through the Corresponding_Discriminant of a
12389 -- new discriminant: if it constrains several old discriminants,
12390 -- this field points to the last one in the parent type. The
12391 -- stored discriminants of the derived type have the same name
12392 -- as those of the parent.
12396 New_Discr : Entity_Id;
12397 Old_Discr : Entity_Id;
12400 Constr := First_Elmt (Stored_Constraint (Typ));
12401 Old_Discr := First_Stored_Discriminant (Typ);
12402 while Present (Constr) loop
12403 if Is_Entity_Name (Node (Constr))
12404 and then Ekind (Entity (Node (Constr))) = E_Discriminant
12406 New_Discr := Entity (Node (Constr));
12408 if Chars (Corresponding_Discriminant (New_Discr)) /=
12411 -- The new discriminant has been used to rename a
12412 -- subsequent old discriminant. Introduce a shadow
12413 -- component for the current old discriminant.
12415 New_C := Create_Component (Old_Discr);
12416 Set_Original_Record_Component (New_C, Old_Discr);
12420 -- The constraint has eliminated the old discriminant.
12421 -- Introduce a shadow component.
12423 New_C := Create_Component (Old_Discr);
12424 Set_Original_Record_Component (New_C, Old_Discr);
12427 Next_Elmt (Constr);
12428 Next_Stored_Discriminant (Old_Discr);
12432 end Add_Discriminants;
12435 and then Is_Variant_Record (Typ)
12437 Collect_Fixed_Components (Typ);
12439 Gather_Components (
12441 Component_List (Type_Definition (Parent (Typ))),
12442 Governed_By => Assoc_List,
12444 Report_Errors => Errors);
12445 pragma Assert (not Errors);
12447 Create_All_Components;
12449 -- If the subtype declaration is created for a tagged type derivation
12450 -- with constraints, we retrieve the record definition of the parent
12451 -- type to select the components of the proper variant.
12454 and then Is_Tagged_Type (Typ)
12455 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
12457 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
12458 and then Is_Variant_Record (Parent_Type)
12460 Collect_Fixed_Components (Typ);
12462 Gather_Components (
12464 Component_List (Type_Definition (Parent (Parent_Type))),
12465 Governed_By => Assoc_List,
12467 Report_Errors => Errors);
12468 pragma Assert (not Errors);
12470 -- If the tagged derivation has a type extension, collect all the
12471 -- new components therein.
12474 (Record_Extension_Part (Type_Definition (Parent (Typ))))
12476 Old_C := First_Component (Typ);
12477 while Present (Old_C) loop
12478 if Original_Record_Component (Old_C) = Old_C
12479 and then Chars (Old_C) /= Name_uTag
12480 and then Chars (Old_C) /= Name_uParent
12482 Append_Elmt (Old_C, Comp_List);
12485 Next_Component (Old_C);
12489 Create_All_Components;
12492 -- If discriminants are not static, or if this is a multi-level type
12493 -- extension, we have to include all components of the parent type.
12495 Old_C := First_Component (Typ);
12496 while Present (Old_C) loop
12497 New_C := Create_Component (Old_C);
12501 Constrain_Component_Type
12502 (Old_C, Subt, Decl_Node, Typ, Constraints));
12503 Set_Is_Public (New_C, Is_Public (Subt));
12505 Next_Component (Old_C);
12510 end Create_Constrained_Components;
12512 ------------------------------------------
12513 -- Decimal_Fixed_Point_Type_Declaration --
12514 ------------------------------------------
12516 procedure Decimal_Fixed_Point_Type_Declaration
12520 Loc : constant Source_Ptr := Sloc (Def);
12521 Digs_Expr : constant Node_Id := Digits_Expression (Def);
12522 Delta_Expr : constant Node_Id := Delta_Expression (Def);
12523 Implicit_Base : Entity_Id;
12530 Check_SPARK_Restriction
12531 ("decimal fixed point type is not allowed", Def);
12532 Check_Restriction (No_Fixed_Point, Def);
12534 -- Create implicit base type
12537 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
12538 Set_Etype (Implicit_Base, Implicit_Base);
12540 -- Analyze and process delta expression
12542 Analyze_And_Resolve (Delta_Expr, Universal_Real);
12544 Check_Delta_Expression (Delta_Expr);
12545 Delta_Val := Expr_Value_R (Delta_Expr);
12547 -- Check delta is power of 10, and determine scale value from it
12553 Scale_Val := Uint_0;
12556 if Val < Ureal_1 then
12557 while Val < Ureal_1 loop
12558 Val := Val * Ureal_10;
12559 Scale_Val := Scale_Val + 1;
12562 if Scale_Val > 18 then
12563 Error_Msg_N ("scale exceeds maximum value of 18", Def);
12564 Scale_Val := UI_From_Int (+18);
12568 while Val > Ureal_1 loop
12569 Val := Val / Ureal_10;
12570 Scale_Val := Scale_Val - 1;
12573 if Scale_Val < -18 then
12574 Error_Msg_N ("scale is less than minimum value of -18", Def);
12575 Scale_Val := UI_From_Int (-18);
12579 if Val /= Ureal_1 then
12580 Error_Msg_N ("delta expression must be a power of 10", Def);
12581 Delta_Val := Ureal_10 ** (-Scale_Val);
12585 -- Set delta, scale and small (small = delta for decimal type)
12587 Set_Delta_Value (Implicit_Base, Delta_Val);
12588 Set_Scale_Value (Implicit_Base, Scale_Val);
12589 Set_Small_Value (Implicit_Base, Delta_Val);
12591 -- Analyze and process digits expression
12593 Analyze_And_Resolve (Digs_Expr, Any_Integer);
12594 Check_Digits_Expression (Digs_Expr);
12595 Digs_Val := Expr_Value (Digs_Expr);
12597 if Digs_Val > 18 then
12598 Digs_Val := UI_From_Int (+18);
12599 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
12602 Set_Digits_Value (Implicit_Base, Digs_Val);
12603 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
12605 -- Set range of base type from digits value for now. This will be
12606 -- expanded to represent the true underlying base range by Freeze.
12608 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
12610 -- Note: We leave size as zero for now, size will be set at freeze
12611 -- time. We have to do this for ordinary fixed-point, because the size
12612 -- depends on the specified small, and we might as well do the same for
12613 -- decimal fixed-point.
12615 pragma Assert (Esize (Implicit_Base) = Uint_0);
12617 -- If there are bounds given in the declaration use them as the
12618 -- bounds of the first named subtype.
12620 if Present (Real_Range_Specification (Def)) then
12622 RRS : constant Node_Id := Real_Range_Specification (Def);
12623 Low : constant Node_Id := Low_Bound (RRS);
12624 High : constant Node_Id := High_Bound (RRS);
12629 Analyze_And_Resolve (Low, Any_Real);
12630 Analyze_And_Resolve (High, Any_Real);
12631 Check_Real_Bound (Low);
12632 Check_Real_Bound (High);
12633 Low_Val := Expr_Value_R (Low);
12634 High_Val := Expr_Value_R (High);
12636 if Low_Val < (-Bound_Val) then
12638 ("range low bound too small for digits value", Low);
12639 Low_Val := -Bound_Val;
12642 if High_Val > Bound_Val then
12644 ("range high bound too large for digits value", High);
12645 High_Val := Bound_Val;
12648 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
12651 -- If no explicit range, use range that corresponds to given
12652 -- digits value. This will end up as the final range for the
12656 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
12659 -- Complete entity for first subtype
12661 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
12662 Set_Etype (T, Implicit_Base);
12663 Set_Size_Info (T, Implicit_Base);
12664 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
12665 Set_Digits_Value (T, Digs_Val);
12666 Set_Delta_Value (T, Delta_Val);
12667 Set_Small_Value (T, Delta_Val);
12668 Set_Scale_Value (T, Scale_Val);
12669 Set_Is_Constrained (T);
12670 end Decimal_Fixed_Point_Type_Declaration;
12672 -----------------------------------
12673 -- Derive_Progenitor_Subprograms --
12674 -----------------------------------
12676 procedure Derive_Progenitor_Subprograms
12677 (Parent_Type : Entity_Id;
12678 Tagged_Type : Entity_Id)
12683 Iface_Elmt : Elmt_Id;
12684 Iface_Subp : Entity_Id;
12685 New_Subp : Entity_Id := Empty;
12686 Prim_Elmt : Elmt_Id;
12691 pragma Assert (Ada_Version >= Ada_2005
12692 and then Is_Record_Type (Tagged_Type)
12693 and then Is_Tagged_Type (Tagged_Type)
12694 and then Has_Interfaces (Tagged_Type));
12696 -- Step 1: Transfer to the full-view primitives associated with the
12697 -- partial-view that cover interface primitives. Conceptually this
12698 -- work should be done later by Process_Full_View; done here to
12699 -- simplify its implementation at later stages. It can be safely
12700 -- done here because interfaces must be visible in the partial and
12701 -- private view (RM 7.3(7.3/2)).
12703 -- Small optimization: This work is only required if the parent is
12704 -- abstract. If the tagged type is not abstract, it cannot have
12705 -- abstract primitives (the only entities in the list of primitives of
12706 -- non-abstract tagged types that can reference abstract primitives
12707 -- through its Alias attribute are the internal entities that have
12708 -- attribute Interface_Alias, and these entities are generated later
12709 -- by Add_Internal_Interface_Entities).
12711 if In_Private_Part (Current_Scope)
12712 and then Is_Abstract_Type (Parent_Type)
12714 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
12715 while Present (Elmt) loop
12716 Subp := Node (Elmt);
12718 -- At this stage it is not possible to have entities in the list
12719 -- of primitives that have attribute Interface_Alias
12721 pragma Assert (No (Interface_Alias (Subp)));
12723 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
12725 if Is_Interface (Typ) then
12726 E := Find_Primitive_Covering_Interface
12727 (Tagged_Type => Tagged_Type,
12728 Iface_Prim => Subp);
12731 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
12733 Replace_Elmt (Elmt, E);
12734 Remove_Homonym (Subp);
12742 -- Step 2: Add primitives of progenitors that are not implemented by
12743 -- parents of Tagged_Type
12745 if Present (Interfaces (Base_Type (Tagged_Type))) then
12746 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
12747 while Present (Iface_Elmt) loop
12748 Iface := Node (Iface_Elmt);
12750 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
12751 while Present (Prim_Elmt) loop
12752 Iface_Subp := Node (Prim_Elmt);
12754 -- Exclude derivation of predefined primitives except those
12755 -- that come from source. Required to catch declarations of
12756 -- equality operators of interfaces. For example:
12758 -- type Iface is interface;
12759 -- function "=" (Left, Right : Iface) return Boolean;
12761 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
12762 or else Comes_From_Source (Iface_Subp)
12764 E := Find_Primitive_Covering_Interface
12765 (Tagged_Type => Tagged_Type,
12766 Iface_Prim => Iface_Subp);
12768 -- If not found we derive a new primitive leaving its alias
12769 -- attribute referencing the interface primitive
12773 (New_Subp, Iface_Subp, Tagged_Type, Iface);
12775 -- Ada 2012 (AI05-0197): If the covering primitive's name
12776 -- differs from the name of the interface primitive then it
12777 -- is a private primitive inherited from a parent type. In
12778 -- such case, given that Tagged_Type covers the interface,
12779 -- the inherited private primitive becomes visible. For such
12780 -- purpose we add a new entity that renames the inherited
12781 -- private primitive.
12783 elsif Chars (E) /= Chars (Iface_Subp) then
12784 pragma Assert (Has_Suffix (E, 'P'));
12786 (New_Subp, Iface_Subp, Tagged_Type, Iface);
12787 Set_Alias (New_Subp, E);
12788 Set_Is_Abstract_Subprogram (New_Subp,
12789 Is_Abstract_Subprogram (E));
12791 -- Propagate to the full view interface entities associated
12792 -- with the partial view
12794 elsif In_Private_Part (Current_Scope)
12795 and then Present (Alias (E))
12796 and then Alias (E) = Iface_Subp
12798 List_Containing (Parent (E)) /=
12799 Private_Declarations
12801 (Unit_Declaration_Node (Current_Scope)))
12803 Append_Elmt (E, Primitive_Operations (Tagged_Type));
12807 Next_Elmt (Prim_Elmt);
12810 Next_Elmt (Iface_Elmt);
12813 end Derive_Progenitor_Subprograms;
12815 -----------------------
12816 -- Derive_Subprogram --
12817 -----------------------
12819 procedure Derive_Subprogram
12820 (New_Subp : in out Entity_Id;
12821 Parent_Subp : Entity_Id;
12822 Derived_Type : Entity_Id;
12823 Parent_Type : Entity_Id;
12824 Actual_Subp : Entity_Id := Empty)
12826 Formal : Entity_Id;
12827 -- Formal parameter of parent primitive operation
12829 Formal_Of_Actual : Entity_Id;
12830 -- Formal parameter of actual operation, when the derivation is to
12831 -- create a renaming for a primitive operation of an actual in an
12834 New_Formal : Entity_Id;
12835 -- Formal of inherited operation
12837 Visible_Subp : Entity_Id := Parent_Subp;
12839 function Is_Private_Overriding return Boolean;
12840 -- If Subp is a private overriding of a visible operation, the inherited
12841 -- operation derives from the overridden op (even though its body is the
12842 -- overriding one) and the inherited operation is visible now. See
12843 -- sem_disp to see the full details of the handling of the overridden
12844 -- subprogram, which is removed from the list of primitive operations of
12845 -- the type. The overridden subprogram is saved locally in Visible_Subp,
12846 -- and used to diagnose abstract operations that need overriding in the
12849 procedure Replace_Type (Id, New_Id : Entity_Id);
12850 -- When the type is an anonymous access type, create a new access type
12851 -- designating the derived type.
12853 procedure Set_Derived_Name;
12854 -- This procedure sets the appropriate Chars name for New_Subp. This
12855 -- is normally just a copy of the parent name. An exception arises for
12856 -- type support subprograms, where the name is changed to reflect the
12857 -- name of the derived type, e.g. if type foo is derived from type bar,
12858 -- then a procedure barDA is derived with a name fooDA.
12860 ---------------------------
12861 -- Is_Private_Overriding --
12862 ---------------------------
12864 function Is_Private_Overriding return Boolean is
12868 -- If the parent is not a dispatching operation there is no
12869 -- need to investigate overridings
12871 if not Is_Dispatching_Operation (Parent_Subp) then
12875 -- The visible operation that is overridden is a homonym of the
12876 -- parent subprogram. We scan the homonym chain to find the one
12877 -- whose alias is the subprogram we are deriving.
12879 Prev := Current_Entity (Parent_Subp);
12880 while Present (Prev) loop
12881 if Ekind (Prev) = Ekind (Parent_Subp)
12882 and then Alias (Prev) = Parent_Subp
12883 and then Scope (Parent_Subp) = Scope (Prev)
12884 and then not Is_Hidden (Prev)
12886 Visible_Subp := Prev;
12890 Prev := Homonym (Prev);
12894 end Is_Private_Overriding;
12900 procedure Replace_Type (Id, New_Id : Entity_Id) is
12901 Acc_Type : Entity_Id;
12902 Par : constant Node_Id := Parent (Derived_Type);
12905 -- When the type is an anonymous access type, create a new access
12906 -- type designating the derived type. This itype must be elaborated
12907 -- at the point of the derivation, not on subsequent calls that may
12908 -- be out of the proper scope for Gigi, so we insert a reference to
12909 -- it after the derivation.
12911 if Ekind (Etype (Id)) = E_Anonymous_Access_Type then
12913 Desig_Typ : Entity_Id := Designated_Type (Etype (Id));
12916 if Ekind (Desig_Typ) = E_Record_Type_With_Private
12917 and then Present (Full_View (Desig_Typ))
12918 and then not Is_Private_Type (Parent_Type)
12920 Desig_Typ := Full_View (Desig_Typ);
12923 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
12925 -- Ada 2005 (AI-251): Handle also derivations of abstract
12926 -- interface primitives.
12928 or else (Is_Interface (Desig_Typ)
12929 and then not Is_Class_Wide_Type (Desig_Typ))
12931 Acc_Type := New_Copy (Etype (Id));
12932 Set_Etype (Acc_Type, Acc_Type);
12933 Set_Scope (Acc_Type, New_Subp);
12935 -- Compute size of anonymous access type
12937 if Is_Array_Type (Desig_Typ)
12938 and then not Is_Constrained (Desig_Typ)
12940 Init_Size (Acc_Type, 2 * System_Address_Size);
12942 Init_Size (Acc_Type, System_Address_Size);
12945 Init_Alignment (Acc_Type);
12946 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
12948 Set_Etype (New_Id, Acc_Type);
12949 Set_Scope (New_Id, New_Subp);
12951 -- Create a reference to it
12952 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
12955 Set_Etype (New_Id, Etype (Id));
12959 elsif Base_Type (Etype (Id)) = Base_Type (Parent_Type)
12961 (Ekind (Etype (Id)) = E_Record_Type_With_Private
12962 and then Present (Full_View (Etype (Id)))
12964 Base_Type (Full_View (Etype (Id))) = Base_Type (Parent_Type))
12966 -- Constraint checks on formals are generated during expansion,
12967 -- based on the signature of the original subprogram. The bounds
12968 -- of the derived type are not relevant, and thus we can use
12969 -- the base type for the formals. However, the return type may be
12970 -- used in a context that requires that the proper static bounds
12971 -- be used (a case statement, for example) and for those cases
12972 -- we must use the derived type (first subtype), not its base.
12974 -- If the derived_type_definition has no constraints, we know that
12975 -- the derived type has the same constraints as the first subtype
12976 -- of the parent, and we can also use it rather than its base,
12977 -- which can lead to more efficient code.
12979 if Etype (Id) = Parent_Type then
12980 if Is_Scalar_Type (Parent_Type)
12982 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
12984 Set_Etype (New_Id, Derived_Type);
12986 elsif Nkind (Par) = N_Full_Type_Declaration
12988 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
12991 (Subtype_Indication (Type_Definition (Par)))
12993 Set_Etype (New_Id, Derived_Type);
12996 Set_Etype (New_Id, Base_Type (Derived_Type));
13000 Set_Etype (New_Id, Base_Type (Derived_Type));
13004 Set_Etype (New_Id, Etype (Id));
13008 ----------------------
13009 -- Set_Derived_Name --
13010 ----------------------
13012 procedure Set_Derived_Name is
13013 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
13015 if Nm = TSS_Null then
13016 Set_Chars (New_Subp, Chars (Parent_Subp));
13018 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
13020 end Set_Derived_Name;
13022 -- Start of processing for Derive_Subprogram
13026 New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
13027 Set_Ekind (New_Subp, Ekind (Parent_Subp));
13029 -- Check whether the inherited subprogram is a private operation that
13030 -- should be inherited but not yet made visible. Such subprograms can
13031 -- become visible at a later point (e.g., the private part of a public
13032 -- child unit) via Declare_Inherited_Private_Subprograms. If the
13033 -- following predicate is true, then this is not such a private
13034 -- operation and the subprogram simply inherits the name of the parent
13035 -- subprogram. Note the special check for the names of controlled
13036 -- operations, which are currently exempted from being inherited with
13037 -- a hidden name because they must be findable for generation of
13038 -- implicit run-time calls.
13040 if not Is_Hidden (Parent_Subp)
13041 or else Is_Internal (Parent_Subp)
13042 or else Is_Private_Overriding
13043 or else Is_Internal_Name (Chars (Parent_Subp))
13044 or else Chars (Parent_Subp) = Name_Initialize
13045 or else Chars (Parent_Subp) = Name_Adjust
13046 or else Chars (Parent_Subp) = Name_Finalize
13050 -- An inherited dispatching equality will be overridden by an internally
13051 -- generated one, or by an explicit one, so preserve its name and thus
13052 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
13053 -- private operation it may become invisible if the full view has
13054 -- progenitors, and the dispatch table will be malformed.
13055 -- We check that the type is limited to handle the anomalous declaration
13056 -- of Limited_Controlled, which is derived from a non-limited type, and
13057 -- which is handled specially elsewhere as well.
13059 elsif Chars (Parent_Subp) = Name_Op_Eq
13060 and then Is_Dispatching_Operation (Parent_Subp)
13061 and then Etype (Parent_Subp) = Standard_Boolean
13062 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
13064 Etype (First_Formal (Parent_Subp)) =
13065 Etype (Next_Formal (First_Formal (Parent_Subp)))
13069 -- If parent is hidden, this can be a regular derivation if the
13070 -- parent is immediately visible in a non-instantiating context,
13071 -- or if we are in the private part of an instance. This test
13072 -- should still be refined ???
13074 -- The test for In_Instance_Not_Visible avoids inheriting the derived
13075 -- operation as a non-visible operation in cases where the parent
13076 -- subprogram might not be visible now, but was visible within the
13077 -- original generic, so it would be wrong to make the inherited
13078 -- subprogram non-visible now. (Not clear if this test is fully
13079 -- correct; are there any cases where we should declare the inherited
13080 -- operation as not visible to avoid it being overridden, e.g., when
13081 -- the parent type is a generic actual with private primitives ???)
13083 -- (they should be treated the same as other private inherited
13084 -- subprograms, but it's not clear how to do this cleanly). ???
13086 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
13087 and then Is_Immediately_Visible (Parent_Subp)
13088 and then not In_Instance)
13089 or else In_Instance_Not_Visible
13093 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
13094 -- overrides an interface primitive because interface primitives
13095 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
13097 elsif Ada_Version >= Ada_2005
13098 and then Is_Dispatching_Operation (Parent_Subp)
13099 and then Covers_Some_Interface (Parent_Subp)
13103 -- Otherwise, the type is inheriting a private operation, so enter
13104 -- it with a special name so it can't be overridden.
13107 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
13110 Set_Parent (New_Subp, Parent (Derived_Type));
13112 if Present (Actual_Subp) then
13113 Replace_Type (Actual_Subp, New_Subp);
13115 Replace_Type (Parent_Subp, New_Subp);
13118 Conditional_Delay (New_Subp, Parent_Subp);
13120 -- If we are creating a renaming for a primitive operation of an
13121 -- actual of a generic derived type, we must examine the signature
13122 -- of the actual primitive, not that of the generic formal, which for
13123 -- example may be an interface. However the name and initial value
13124 -- of the inherited operation are those of the formal primitive.
13126 Formal := First_Formal (Parent_Subp);
13128 if Present (Actual_Subp) then
13129 Formal_Of_Actual := First_Formal (Actual_Subp);
13131 Formal_Of_Actual := Empty;
13134 while Present (Formal) loop
13135 New_Formal := New_Copy (Formal);
13137 -- Normally we do not go copying parents, but in the case of
13138 -- formals, we need to link up to the declaration (which is the
13139 -- parameter specification), and it is fine to link up to the
13140 -- original formal's parameter specification in this case.
13142 Set_Parent (New_Formal, Parent (Formal));
13143 Append_Entity (New_Formal, New_Subp);
13145 if Present (Formal_Of_Actual) then
13146 Replace_Type (Formal_Of_Actual, New_Formal);
13147 Next_Formal (Formal_Of_Actual);
13149 Replace_Type (Formal, New_Formal);
13152 Next_Formal (Formal);
13155 -- If this derivation corresponds to a tagged generic actual, then
13156 -- primitive operations rename those of the actual. Otherwise the
13157 -- primitive operations rename those of the parent type, If the parent
13158 -- renames an intrinsic operator, so does the new subprogram. We except
13159 -- concatenation, which is always properly typed, and does not get
13160 -- expanded as other intrinsic operations.
13162 if No (Actual_Subp) then
13163 if Is_Intrinsic_Subprogram (Parent_Subp) then
13164 Set_Is_Intrinsic_Subprogram (New_Subp);
13166 if Present (Alias (Parent_Subp))
13167 and then Chars (Parent_Subp) /= Name_Op_Concat
13169 Set_Alias (New_Subp, Alias (Parent_Subp));
13171 Set_Alias (New_Subp, Parent_Subp);
13175 Set_Alias (New_Subp, Parent_Subp);
13179 Set_Alias (New_Subp, Actual_Subp);
13182 -- Derived subprograms of a tagged type must inherit the convention
13183 -- of the parent subprogram (a requirement of AI-117). Derived
13184 -- subprograms of untagged types simply get convention Ada by default.
13186 if Is_Tagged_Type (Derived_Type) then
13187 Set_Convention (New_Subp, Convention (Parent_Subp));
13190 -- Predefined controlled operations retain their name even if the parent
13191 -- is hidden (see above), but they are not primitive operations if the
13192 -- ancestor is not visible, for example if the parent is a private
13193 -- extension completed with a controlled extension. Note that a full
13194 -- type that is controlled can break privacy: the flag Is_Controlled is
13195 -- set on both views of the type.
13197 if Is_Controlled (Parent_Type)
13199 (Chars (Parent_Subp) = Name_Initialize
13200 or else Chars (Parent_Subp) = Name_Adjust
13201 or else Chars (Parent_Subp) = Name_Finalize)
13202 and then Is_Hidden (Parent_Subp)
13203 and then not Is_Visibly_Controlled (Parent_Type)
13205 Set_Is_Hidden (New_Subp);
13208 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
13209 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
13211 if Ekind (Parent_Subp) = E_Procedure then
13212 Set_Is_Valued_Procedure
13213 (New_Subp, Is_Valued_Procedure (Parent_Subp));
13215 Set_Has_Controlling_Result
13216 (New_Subp, Has_Controlling_Result (Parent_Subp));
13219 -- No_Return must be inherited properly. If this is overridden in the
13220 -- case of a dispatching operation, then a check is made in Sem_Disp
13221 -- that the overriding operation is also No_Return (no such check is
13222 -- required for the case of non-dispatching operation.
13224 Set_No_Return (New_Subp, No_Return (Parent_Subp));
13226 -- A derived function with a controlling result is abstract. If the
13227 -- Derived_Type is a nonabstract formal generic derived type, then
13228 -- inherited operations are not abstract: the required check is done at
13229 -- instantiation time. If the derivation is for a generic actual, the
13230 -- function is not abstract unless the actual is.
13232 if Is_Generic_Type (Derived_Type)
13233 and then not Is_Abstract_Type (Derived_Type)
13237 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
13238 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
13240 elsif Ada_Version >= Ada_2005
13241 and then (Is_Abstract_Subprogram (Alias (New_Subp))
13242 or else (Is_Tagged_Type (Derived_Type)
13243 and then Etype (New_Subp) = Derived_Type
13244 and then not Is_Null_Extension (Derived_Type))
13245 or else (Is_Tagged_Type (Derived_Type)
13246 and then Ekind (Etype (New_Subp)) =
13247 E_Anonymous_Access_Type
13248 and then Designated_Type (Etype (New_Subp)) =
13250 and then not Is_Null_Extension (Derived_Type)))
13251 and then No (Actual_Subp)
13253 if not Is_Tagged_Type (Derived_Type)
13254 or else Is_Abstract_Type (Derived_Type)
13255 or else Is_Abstract_Subprogram (Alias (New_Subp))
13257 Set_Is_Abstract_Subprogram (New_Subp);
13259 Set_Requires_Overriding (New_Subp);
13262 elsif Ada_Version < Ada_2005
13263 and then (Is_Abstract_Subprogram (Alias (New_Subp))
13264 or else (Is_Tagged_Type (Derived_Type)
13265 and then Etype (New_Subp) = Derived_Type
13266 and then No (Actual_Subp)))
13268 Set_Is_Abstract_Subprogram (New_Subp);
13270 -- AI05-0097 : an inherited operation that dispatches on result is
13271 -- abstract if the derived type is abstract, even if the parent type
13272 -- is concrete and the derived type is a null extension.
13274 elsif Has_Controlling_Result (Alias (New_Subp))
13275 and then Is_Abstract_Type (Etype (New_Subp))
13277 Set_Is_Abstract_Subprogram (New_Subp);
13279 -- Finally, if the parent type is abstract we must verify that all
13280 -- inherited operations are either non-abstract or overridden, or that
13281 -- the derived type itself is abstract (this check is performed at the
13282 -- end of a package declaration, in Check_Abstract_Overriding). A
13283 -- private overriding in the parent type will not be visible in the
13284 -- derivation if we are not in an inner package or in a child unit of
13285 -- the parent type, in which case the abstractness of the inherited
13286 -- operation is carried to the new subprogram.
13288 elsif Is_Abstract_Type (Parent_Type)
13289 and then not In_Open_Scopes (Scope (Parent_Type))
13290 and then Is_Private_Overriding
13291 and then Is_Abstract_Subprogram (Visible_Subp)
13293 if No (Actual_Subp) then
13294 Set_Alias (New_Subp, Visible_Subp);
13295 Set_Is_Abstract_Subprogram (New_Subp, True);
13298 -- If this is a derivation for an instance of a formal derived
13299 -- type, abstractness comes from the primitive operation of the
13300 -- actual, not from the operation inherited from the ancestor.
13302 Set_Is_Abstract_Subprogram
13303 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
13307 New_Overloaded_Entity (New_Subp, Derived_Type);
13309 -- Check for case of a derived subprogram for the instantiation of a
13310 -- formal derived tagged type, if so mark the subprogram as dispatching
13311 -- and inherit the dispatching attributes of the parent subprogram. The
13312 -- derived subprogram is effectively renaming of the actual subprogram,
13313 -- so it needs to have the same attributes as the actual.
13315 if Present (Actual_Subp)
13316 and then Is_Dispatching_Operation (Parent_Subp)
13318 Set_Is_Dispatching_Operation (New_Subp);
13320 if Present (DTC_Entity (Parent_Subp)) then
13321 Set_DTC_Entity (New_Subp, DTC_Entity (Parent_Subp));
13322 Set_DT_Position (New_Subp, DT_Position (Parent_Subp));
13326 -- Indicate that a derived subprogram does not require a body and that
13327 -- it does not require processing of default expressions.
13329 Set_Has_Completion (New_Subp);
13330 Set_Default_Expressions_Processed (New_Subp);
13332 if Ekind (New_Subp) = E_Function then
13333 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
13335 end Derive_Subprogram;
13337 ------------------------
13338 -- Derive_Subprograms --
13339 ------------------------
13341 procedure Derive_Subprograms
13342 (Parent_Type : Entity_Id;
13343 Derived_Type : Entity_Id;
13344 Generic_Actual : Entity_Id := Empty)
13346 Op_List : constant Elist_Id :=
13347 Collect_Primitive_Operations (Parent_Type);
13349 function Check_Derived_Type return Boolean;
13350 -- Check that all the entities derived from Parent_Type are found in
13351 -- the list of primitives of Derived_Type exactly in the same order.
13353 procedure Derive_Interface_Subprogram
13354 (New_Subp : in out Entity_Id;
13356 Actual_Subp : Entity_Id);
13357 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
13358 -- (which is an interface primitive). If Generic_Actual is present then
13359 -- Actual_Subp is the actual subprogram corresponding with the generic
13360 -- subprogram Subp.
13362 function Check_Derived_Type return Boolean is
13366 New_Subp : Entity_Id;
13371 -- Traverse list of entities in the current scope searching for
13372 -- an incomplete type whose full-view is derived type
13374 E := First_Entity (Scope (Derived_Type));
13376 and then E /= Derived_Type
13378 if Ekind (E) = E_Incomplete_Type
13379 and then Present (Full_View (E))
13380 and then Full_View (E) = Derived_Type
13382 -- Disable this test if Derived_Type completes an incomplete
13383 -- type because in such case more primitives can be added
13384 -- later to the list of primitives of Derived_Type by routine
13385 -- Process_Incomplete_Dependents
13390 E := Next_Entity (E);
13393 List := Collect_Primitive_Operations (Derived_Type);
13394 Elmt := First_Elmt (List);
13396 Op_Elmt := First_Elmt (Op_List);
13397 while Present (Op_Elmt) loop
13398 Subp := Node (Op_Elmt);
13399 New_Subp := Node (Elmt);
13401 -- At this early stage Derived_Type has no entities with attribute
13402 -- Interface_Alias. In addition, such primitives are always
13403 -- located at the end of the list of primitives of Parent_Type.
13404 -- Therefore, if found we can safely stop processing pending
13407 exit when Present (Interface_Alias (Subp));
13409 -- Handle hidden entities
13411 if not Is_Predefined_Dispatching_Operation (Subp)
13412 and then Is_Hidden (Subp)
13414 if Present (New_Subp)
13415 and then Primitive_Names_Match (Subp, New_Subp)
13421 if not Present (New_Subp)
13422 or else Ekind (Subp) /= Ekind (New_Subp)
13423 or else not Primitive_Names_Match (Subp, New_Subp)
13431 Next_Elmt (Op_Elmt);
13435 end Check_Derived_Type;
13437 ---------------------------------
13438 -- Derive_Interface_Subprogram --
13439 ---------------------------------
13441 procedure Derive_Interface_Subprogram
13442 (New_Subp : in out Entity_Id;
13444 Actual_Subp : Entity_Id)
13446 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
13447 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
13450 pragma Assert (Is_Interface (Iface_Type));
13453 (New_Subp => New_Subp,
13454 Parent_Subp => Iface_Subp,
13455 Derived_Type => Derived_Type,
13456 Parent_Type => Iface_Type,
13457 Actual_Subp => Actual_Subp);
13459 -- Given that this new interface entity corresponds with a primitive
13460 -- of the parent that was not overridden we must leave it associated
13461 -- with its parent primitive to ensure that it will share the same
13462 -- dispatch table slot when overridden.
13464 if No (Actual_Subp) then
13465 Set_Alias (New_Subp, Subp);
13467 -- For instantiations this is not needed since the previous call to
13468 -- Derive_Subprogram leaves the entity well decorated.
13471 pragma Assert (Alias (New_Subp) = Actual_Subp);
13474 end Derive_Interface_Subprogram;
13478 Alias_Subp : Entity_Id;
13479 Act_List : Elist_Id;
13480 Act_Elmt : Elmt_Id := No_Elmt;
13481 Act_Subp : Entity_Id := Empty;
13483 Need_Search : Boolean := False;
13484 New_Subp : Entity_Id := Empty;
13485 Parent_Base : Entity_Id;
13488 -- Start of processing for Derive_Subprograms
13491 if Ekind (Parent_Type) = E_Record_Type_With_Private
13492 and then Has_Discriminants (Parent_Type)
13493 and then Present (Full_View (Parent_Type))
13495 Parent_Base := Full_View (Parent_Type);
13497 Parent_Base := Parent_Type;
13500 if Present (Generic_Actual) then
13501 Act_List := Collect_Primitive_Operations (Generic_Actual);
13502 Act_Elmt := First_Elmt (Act_List);
13505 -- Derive primitives inherited from the parent. Note that if the generic
13506 -- actual is present, this is not really a type derivation, it is a
13507 -- completion within an instance.
13509 -- Case 1: Derived_Type does not implement interfaces
13511 if not Is_Tagged_Type (Derived_Type)
13512 or else (not Has_Interfaces (Derived_Type)
13513 and then not (Present (Generic_Actual)
13515 Has_Interfaces (Generic_Actual)))
13517 Elmt := First_Elmt (Op_List);
13518 while Present (Elmt) loop
13519 Subp := Node (Elmt);
13521 -- Literals are derived earlier in the process of building the
13522 -- derived type, and are skipped here.
13524 if Ekind (Subp) = E_Enumeration_Literal then
13527 -- The actual is a direct descendant and the common primitive
13528 -- operations appear in the same order.
13530 -- If the generic parent type is present, the derived type is an
13531 -- instance of a formal derived type, and within the instance its
13532 -- operations are those of the actual. We derive from the formal
13533 -- type but make the inherited operations aliases of the
13534 -- corresponding operations of the actual.
13537 pragma Assert (No (Node (Act_Elmt))
13538 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
13540 Type_Conformant (Subp, Node (Act_Elmt),
13541 Skip_Controlling_Formals => True)));
13544 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
13546 if Present (Act_Elmt) then
13547 Next_Elmt (Act_Elmt);
13554 -- Case 2: Derived_Type implements interfaces
13557 -- If the parent type has no predefined primitives we remove
13558 -- predefined primitives from the list of primitives of generic
13559 -- actual to simplify the complexity of this algorithm.
13561 if Present (Generic_Actual) then
13563 Has_Predefined_Primitives : Boolean := False;
13566 -- Check if the parent type has predefined primitives
13568 Elmt := First_Elmt (Op_List);
13569 while Present (Elmt) loop
13570 Subp := Node (Elmt);
13572 if Is_Predefined_Dispatching_Operation (Subp)
13573 and then not Comes_From_Source (Ultimate_Alias (Subp))
13575 Has_Predefined_Primitives := True;
13582 -- Remove predefined primitives of Generic_Actual. We must use
13583 -- an auxiliary list because in case of tagged types the value
13584 -- returned by Collect_Primitive_Operations is the value stored
13585 -- in its Primitive_Operations attribute (and we don't want to
13586 -- modify its current contents).
13588 if not Has_Predefined_Primitives then
13590 Aux_List : constant Elist_Id := New_Elmt_List;
13593 Elmt := First_Elmt (Act_List);
13594 while Present (Elmt) loop
13595 Subp := Node (Elmt);
13597 if not Is_Predefined_Dispatching_Operation (Subp)
13598 or else Comes_From_Source (Subp)
13600 Append_Elmt (Subp, Aux_List);
13606 Act_List := Aux_List;
13610 Act_Elmt := First_Elmt (Act_List);
13611 Act_Subp := Node (Act_Elmt);
13615 -- Stage 1: If the generic actual is not present we derive the
13616 -- primitives inherited from the parent type. If the generic parent
13617 -- type is present, the derived type is an instance of a formal
13618 -- derived type, and within the instance its operations are those of
13619 -- the actual. We derive from the formal type but make the inherited
13620 -- operations aliases of the corresponding operations of the actual.
13622 Elmt := First_Elmt (Op_List);
13623 while Present (Elmt) loop
13624 Subp := Node (Elmt);
13625 Alias_Subp := Ultimate_Alias (Subp);
13627 -- Do not derive internal entities of the parent that link
13628 -- interface primitives with their covering primitive. These
13629 -- entities will be added to this type when frozen.
13631 if Present (Interface_Alias (Subp)) then
13635 -- If the generic actual is present find the corresponding
13636 -- operation in the generic actual. If the parent type is a
13637 -- direct ancestor of the derived type then, even if it is an
13638 -- interface, the operations are inherited from the primary
13639 -- dispatch table and are in the proper order. If we detect here
13640 -- that primitives are not in the same order we traverse the list
13641 -- of primitive operations of the actual to find the one that
13642 -- implements the interface primitive.
13646 (Present (Generic_Actual)
13647 and then Present (Act_Subp)
13649 (Primitive_Names_Match (Subp, Act_Subp)
13651 Type_Conformant (Subp, Act_Subp,
13652 Skip_Controlling_Formals => True)))
13654 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual));
13656 -- Remember that we need searching for all pending primitives
13658 Need_Search := True;
13660 -- Handle entities associated with interface primitives
13662 if Present (Alias_Subp)
13663 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
13664 and then not Is_Predefined_Dispatching_Operation (Subp)
13666 -- Search for the primitive in the homonym chain
13669 Find_Primitive_Covering_Interface
13670 (Tagged_Type => Generic_Actual,
13671 Iface_Prim => Alias_Subp);
13673 -- Previous search may not locate primitives covering
13674 -- interfaces defined in generics units or instantiations.
13675 -- (it fails if the covering primitive has formals whose
13676 -- type is also defined in generics or instantiations).
13677 -- In such case we search in the list of primitives of the
13678 -- generic actual for the internal entity that links the
13679 -- interface primitive and the covering primitive.
13682 and then Is_Generic_Type (Parent_Type)
13684 -- This code has been designed to handle only generic
13685 -- formals that implement interfaces that are defined
13686 -- in a generic unit or instantiation. If this code is
13687 -- needed for other cases we must review it because
13688 -- (given that it relies on Original_Location to locate
13689 -- the primitive of Generic_Actual that covers the
13690 -- interface) it could leave linked through attribute
13691 -- Alias entities of unrelated instantiations).
13695 (Scope (Find_Dispatching_Type (Alias_Subp)))
13697 Instantiation_Depth
13698 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
13701 Iface_Prim_Loc : constant Source_Ptr :=
13702 Original_Location (Sloc (Alias_Subp));
13707 First_Elmt (Primitive_Operations (Generic_Actual));
13709 Search : while Present (Elmt) loop
13710 Prim := Node (Elmt);
13712 if Present (Interface_Alias (Prim))
13713 and then Original_Location
13714 (Sloc (Interface_Alias (Prim)))
13717 Act_Subp := Alias (Prim);
13726 pragma Assert (Present (Act_Subp)
13727 or else Is_Abstract_Type (Generic_Actual)
13728 or else Serious_Errors_Detected > 0);
13730 -- Handle predefined primitives plus the rest of user-defined
13734 Act_Elmt := First_Elmt (Act_List);
13735 while Present (Act_Elmt) loop
13736 Act_Subp := Node (Act_Elmt);
13738 exit when Primitive_Names_Match (Subp, Act_Subp)
13739 and then Type_Conformant
13741 Skip_Controlling_Formals => True)
13742 and then No (Interface_Alias (Act_Subp));
13744 Next_Elmt (Act_Elmt);
13747 if No (Act_Elmt) then
13753 -- Case 1: If the parent is a limited interface then it has the
13754 -- predefined primitives of synchronized interfaces. However, the
13755 -- actual type may be a non-limited type and hence it does not
13756 -- have such primitives.
13758 if Present (Generic_Actual)
13759 and then not Present (Act_Subp)
13760 and then Is_Limited_Interface (Parent_Base)
13761 and then Is_Predefined_Interface_Primitive (Subp)
13765 -- Case 2: Inherit entities associated with interfaces that were
13766 -- not covered by the parent type. We exclude here null interface
13767 -- primitives because they do not need special management.
13769 -- We also exclude interface operations that are renamings. If the
13770 -- subprogram is an explicit renaming of an interface primitive,
13771 -- it is a regular primitive operation, and the presence of its
13772 -- alias is not relevant: it has to be derived like any other
13775 elsif Present (Alias (Subp))
13776 and then Nkind (Unit_Declaration_Node (Subp)) /=
13777 N_Subprogram_Renaming_Declaration
13778 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
13780 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
13781 and then Null_Present (Parent (Alias_Subp)))
13783 -- If this is an abstract private type then we transfer the
13784 -- derivation of the interface primitive from the partial view
13785 -- to the full view. This is safe because all the interfaces
13786 -- must be visible in the partial view. Done to avoid adding
13787 -- a new interface derivation to the private part of the
13788 -- enclosing package; otherwise this new derivation would be
13789 -- decorated as hidden when the analysis of the enclosing
13790 -- package completes.
13792 if Is_Abstract_Type (Derived_Type)
13793 and then In_Private_Part (Current_Scope)
13794 and then Has_Private_Declaration (Derived_Type)
13797 Partial_View : Entity_Id;
13802 Partial_View := First_Entity (Current_Scope);
13804 exit when No (Partial_View)
13805 or else (Has_Private_Declaration (Partial_View)
13807 Full_View (Partial_View) = Derived_Type);
13809 Next_Entity (Partial_View);
13812 -- If the partial view was not found then the source code
13813 -- has errors and the derivation is not needed.
13815 if Present (Partial_View) then
13817 First_Elmt (Primitive_Operations (Partial_View));
13818 while Present (Elmt) loop
13819 Ent := Node (Elmt);
13821 if Present (Alias (Ent))
13822 and then Ultimate_Alias (Ent) = Alias (Subp)
13825 (Ent, Primitive_Operations (Derived_Type));
13832 -- If the interface primitive was not found in the
13833 -- partial view then this interface primitive was
13834 -- overridden. We add a derivation to activate in
13835 -- Derive_Progenitor_Subprograms the machinery to
13839 Derive_Interface_Subprogram
13840 (New_Subp => New_Subp,
13842 Actual_Subp => Act_Subp);
13847 Derive_Interface_Subprogram
13848 (New_Subp => New_Subp,
13850 Actual_Subp => Act_Subp);
13853 -- Case 3: Common derivation
13857 (New_Subp => New_Subp,
13858 Parent_Subp => Subp,
13859 Derived_Type => Derived_Type,
13860 Parent_Type => Parent_Base,
13861 Actual_Subp => Act_Subp);
13864 -- No need to update Act_Elm if we must search for the
13865 -- corresponding operation in the generic actual
13868 and then Present (Act_Elmt)
13870 Next_Elmt (Act_Elmt);
13871 Act_Subp := Node (Act_Elmt);
13878 -- Inherit additional operations from progenitors. If the derived
13879 -- type is a generic actual, there are not new primitive operations
13880 -- for the type because it has those of the actual, and therefore
13881 -- nothing needs to be done. The renamings generated above are not
13882 -- primitive operations, and their purpose is simply to make the
13883 -- proper operations visible within an instantiation.
13885 if No (Generic_Actual) then
13886 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
13890 -- Final check: Direct descendants must have their primitives in the
13891 -- same order. We exclude from this test untagged types and instances
13892 -- of formal derived types. We skip this test if we have already
13893 -- reported serious errors in the sources.
13895 pragma Assert (not Is_Tagged_Type (Derived_Type)
13896 or else Present (Generic_Actual)
13897 or else Serious_Errors_Detected > 0
13898 or else Check_Derived_Type);
13899 end Derive_Subprograms;
13901 --------------------------------
13902 -- Derived_Standard_Character --
13903 --------------------------------
13905 procedure Derived_Standard_Character
13907 Parent_Type : Entity_Id;
13908 Derived_Type : Entity_Id)
13910 Loc : constant Source_Ptr := Sloc (N);
13911 Def : constant Node_Id := Type_Definition (N);
13912 Indic : constant Node_Id := Subtype_Indication (Def);
13913 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
13914 Implicit_Base : constant Entity_Id :=
13916 (E_Enumeration_Type, N, Derived_Type, 'B');
13922 Discard_Node (Process_Subtype (Indic, N));
13924 Set_Etype (Implicit_Base, Parent_Base);
13925 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
13926 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
13928 Set_Is_Character_Type (Implicit_Base, True);
13929 Set_Has_Delayed_Freeze (Implicit_Base);
13931 -- The bounds of the implicit base are the bounds of the parent base.
13932 -- Note that their type is the parent base.
13934 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
13935 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
13937 Set_Scalar_Range (Implicit_Base,
13940 High_Bound => Hi));
13942 Conditional_Delay (Derived_Type, Parent_Type);
13944 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
13945 Set_Etype (Derived_Type, Implicit_Base);
13946 Set_Size_Info (Derived_Type, Parent_Type);
13948 if Unknown_RM_Size (Derived_Type) then
13949 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
13952 Set_Is_Character_Type (Derived_Type, True);
13954 if Nkind (Indic) /= N_Subtype_Indication then
13956 -- If no explicit constraint, the bounds are those
13957 -- of the parent type.
13959 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
13960 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
13961 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
13964 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
13966 -- Because the implicit base is used in the conversion of the bounds, we
13967 -- have to freeze it now. This is similar to what is done for numeric
13968 -- types, and it equally suspicious, but otherwise a non-static bound
13969 -- will have a reference to an unfrozen type, which is rejected by Gigi
13970 -- (???). This requires specific care for definition of stream
13971 -- attributes. For details, see comments at the end of
13972 -- Build_Derived_Numeric_Type.
13974 Freeze_Before (N, Implicit_Base);
13975 end Derived_Standard_Character;
13977 ------------------------------
13978 -- Derived_Type_Declaration --
13979 ------------------------------
13981 procedure Derived_Type_Declaration
13984 Is_Completion : Boolean)
13986 Parent_Type : Entity_Id;
13988 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
13989 -- Check whether the parent type is a generic formal, or derives
13990 -- directly or indirectly from one.
13992 ------------------------
13993 -- Comes_From_Generic --
13994 ------------------------
13996 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
13998 if Is_Generic_Type (Typ) then
14001 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
14004 elsif Is_Private_Type (Typ)
14005 and then Present (Full_View (Typ))
14006 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
14010 elsif Is_Generic_Actual_Type (Typ) then
14016 end Comes_From_Generic;
14020 Def : constant Node_Id := Type_Definition (N);
14021 Iface_Def : Node_Id;
14022 Indic : constant Node_Id := Subtype_Indication (Def);
14023 Extension : constant Node_Id := Record_Extension_Part (Def);
14024 Parent_Node : Node_Id;
14027 -- Start of processing for Derived_Type_Declaration
14030 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
14032 -- Ada 2005 (AI-251): In case of interface derivation check that the
14033 -- parent is also an interface.
14035 if Interface_Present (Def) then
14036 Check_SPARK_Restriction ("interface is not allowed", Def);
14038 if not Is_Interface (Parent_Type) then
14039 Diagnose_Interface (Indic, Parent_Type);
14042 Parent_Node := Parent (Base_Type (Parent_Type));
14043 Iface_Def := Type_Definition (Parent_Node);
14045 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
14046 -- other limited interfaces.
14048 if Limited_Present (Def) then
14049 if Limited_Present (Iface_Def) then
14052 elsif Protected_Present (Iface_Def) then
14054 ("descendant of& must be declared"
14055 & " as a protected interface",
14058 elsif Synchronized_Present (Iface_Def) then
14060 ("descendant of& must be declared"
14061 & " as a synchronized interface",
14064 elsif Task_Present (Iface_Def) then
14066 ("descendant of& must be declared as a task interface",
14071 ("(Ada 2005) limited interface cannot "
14072 & "inherit from non-limited interface", Indic);
14075 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
14076 -- from non-limited or limited interfaces.
14078 elsif not Protected_Present (Def)
14079 and then not Synchronized_Present (Def)
14080 and then not Task_Present (Def)
14082 if Limited_Present (Iface_Def) then
14085 elsif Protected_Present (Iface_Def) then
14087 ("descendant of& must be declared"
14088 & " as a protected interface",
14091 elsif Synchronized_Present (Iface_Def) then
14093 ("descendant of& must be declared"
14094 & " as a synchronized interface",
14097 elsif Task_Present (Iface_Def) then
14099 ("descendant of& must be declared as a task interface",
14108 if Is_Tagged_Type (Parent_Type)
14109 and then Is_Concurrent_Type (Parent_Type)
14110 and then not Is_Interface (Parent_Type)
14113 ("parent type of a record extension cannot be "
14114 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
14115 Set_Etype (T, Any_Type);
14119 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
14122 if Is_Tagged_Type (Parent_Type)
14123 and then Is_Non_Empty_List (Interface_List (Def))
14130 Intf := First (Interface_List (Def));
14131 while Present (Intf) loop
14132 T := Find_Type_Of_Subtype_Indic (Intf);
14134 if not Is_Interface (T) then
14135 Diagnose_Interface (Intf, T);
14137 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
14138 -- a limited type from having a nonlimited progenitor.
14140 elsif (Limited_Present (Def)
14141 or else (not Is_Interface (Parent_Type)
14142 and then Is_Limited_Type (Parent_Type)))
14143 and then not Is_Limited_Interface (T)
14146 ("progenitor interface& of limited type must be limited",
14155 if Parent_Type = Any_Type
14156 or else Etype (Parent_Type) = Any_Type
14157 or else (Is_Class_Wide_Type (Parent_Type)
14158 and then Etype (Parent_Type) = T)
14160 -- If Parent_Type is undefined or illegal, make new type into a
14161 -- subtype of Any_Type, and set a few attributes to prevent cascaded
14162 -- errors. If this is a self-definition, emit error now.
14165 or else T = Etype (Parent_Type)
14167 Error_Msg_N ("type cannot be used in its own definition", Indic);
14170 Set_Ekind (T, Ekind (Parent_Type));
14171 Set_Etype (T, Any_Type);
14172 Set_Scalar_Range (T, Scalar_Range (Any_Type));
14174 if Is_Tagged_Type (T)
14175 and then Is_Record_Type (T)
14177 Set_Direct_Primitive_Operations (T, New_Elmt_List);
14183 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
14184 -- an interface is special because the list of interfaces in the full
14185 -- view can be given in any order. For example:
14187 -- type A is interface;
14188 -- type B is interface and A;
14189 -- type D is new B with private;
14191 -- type D is new A and B with null record; -- 1 --
14193 -- In this case we perform the following transformation of -1-:
14195 -- type D is new B and A with null record;
14197 -- If the parent of the full-view covers the parent of the partial-view
14198 -- we have two possible cases:
14200 -- 1) They have the same parent
14201 -- 2) The parent of the full-view implements some further interfaces
14203 -- In both cases we do not need to perform the transformation. In the
14204 -- first case the source program is correct and the transformation is
14205 -- not needed; in the second case the source program does not fulfill
14206 -- the no-hidden interfaces rule (AI-396) and the error will be reported
14209 -- This transformation not only simplifies the rest of the analysis of
14210 -- this type declaration but also simplifies the correct generation of
14211 -- the object layout to the expander.
14213 if In_Private_Part (Current_Scope)
14214 and then Is_Interface (Parent_Type)
14218 Partial_View : Entity_Id;
14219 Partial_View_Parent : Entity_Id;
14220 New_Iface : Node_Id;
14223 -- Look for the associated private type declaration
14225 Partial_View := First_Entity (Current_Scope);
14227 exit when No (Partial_View)
14228 or else (Has_Private_Declaration (Partial_View)
14229 and then Full_View (Partial_View) = T);
14231 Next_Entity (Partial_View);
14234 -- If the partial view was not found then the source code has
14235 -- errors and the transformation is not needed.
14237 if Present (Partial_View) then
14238 Partial_View_Parent := Etype (Partial_View);
14240 -- If the parent of the full-view covers the parent of the
14241 -- partial-view we have nothing else to do.
14243 if Interface_Present_In_Ancestor
14244 (Parent_Type, Partial_View_Parent)
14248 -- Traverse the list of interfaces of the full-view to look
14249 -- for the parent of the partial-view and perform the tree
14253 Iface := First (Interface_List (Def));
14254 while Present (Iface) loop
14255 if Etype (Iface) = Etype (Partial_View) then
14256 Rewrite (Subtype_Indication (Def),
14257 New_Copy (Subtype_Indication
14258 (Parent (Partial_View))));
14261 Make_Identifier (Sloc (N), Chars (Parent_Type));
14262 Append (New_Iface, Interface_List (Def));
14264 -- Analyze the transformed code
14266 Derived_Type_Declaration (T, N, Is_Completion);
14277 -- Only composite types other than array types are allowed to have
14278 -- discriminants. In SPARK, no types are allowed to have discriminants.
14280 if Present (Discriminant_Specifications (N)) then
14281 if (Is_Elementary_Type (Parent_Type)
14282 or else Is_Array_Type (Parent_Type))
14283 and then not Error_Posted (N)
14286 ("elementary or array type cannot have discriminants",
14287 Defining_Identifier (First (Discriminant_Specifications (N))));
14288 Set_Has_Discriminants (T, False);
14290 Check_SPARK_Restriction ("discriminant type is not allowed", N);
14294 -- In Ada 83, a derived type defined in a package specification cannot
14295 -- be used for further derivation until the end of its visible part.
14296 -- Note that derivation in the private part of the package is allowed.
14298 if Ada_Version = Ada_83
14299 and then Is_Derived_Type (Parent_Type)
14300 and then In_Visible_Part (Scope (Parent_Type))
14302 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
14304 ("(Ada 83): premature use of type for derivation", Indic);
14308 -- Check for early use of incomplete or private type
14310 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
14311 Error_Msg_N ("premature derivation of incomplete type", Indic);
14314 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
14315 and then not Comes_From_Generic (Parent_Type))
14316 or else Has_Private_Component (Parent_Type)
14318 -- The ancestor type of a formal type can be incomplete, in which
14319 -- case only the operations of the partial view are available in the
14320 -- generic. Subsequent checks may be required when the full view is
14321 -- analyzed to verify that a derivation from a tagged type has an
14324 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
14327 elsif No (Underlying_Type (Parent_Type))
14328 or else Has_Private_Component (Parent_Type)
14331 ("premature derivation of derived or private type", Indic);
14333 -- Flag the type itself as being in error, this prevents some
14334 -- nasty problems with subsequent uses of the malformed type.
14336 Set_Error_Posted (T);
14338 -- Check that within the immediate scope of an untagged partial
14339 -- view it's illegal to derive from the partial view if the
14340 -- full view is tagged. (7.3(7))
14342 -- We verify that the Parent_Type is a partial view by checking
14343 -- that it is not a Full_Type_Declaration (i.e. a private type or
14344 -- private extension declaration), to distinguish a partial view
14345 -- from a derivation from a private type which also appears as
14346 -- E_Private_Type. If the parent base type is not declared in an
14347 -- enclosing scope there is no need to check.
14349 elsif Present (Full_View (Parent_Type))
14350 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
14351 and then not Is_Tagged_Type (Parent_Type)
14352 and then Is_Tagged_Type (Full_View (Parent_Type))
14353 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
14356 ("premature derivation from type with tagged full view",
14361 -- Check that form of derivation is appropriate
14363 Taggd := Is_Tagged_Type (Parent_Type);
14365 -- Perhaps the parent type should be changed to the class-wide type's
14366 -- specific type in this case to prevent cascading errors ???
14368 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
14369 Error_Msg_N ("parent type must not be a class-wide type", Indic);
14373 if Present (Extension) and then not Taggd then
14375 ("type derived from untagged type cannot have extension", Indic);
14377 elsif No (Extension) and then Taggd then
14379 -- If this declaration is within a private part (or body) of a
14380 -- generic instantiation then the derivation is allowed (the parent
14381 -- type can only appear tagged in this case if it's a generic actual
14382 -- type, since it would otherwise have been rejected in the analysis
14383 -- of the generic template).
14385 if not Is_Generic_Actual_Type (Parent_Type)
14386 or else In_Visible_Part (Scope (Parent_Type))
14388 if Is_Class_Wide_Type (Parent_Type) then
14390 ("parent type must not be a class-wide type", Indic);
14392 -- Use specific type to prevent cascaded errors.
14394 Parent_Type := Etype (Parent_Type);
14398 ("type derived from tagged type must have extension", Indic);
14403 -- AI-443: Synchronized formal derived types require a private
14404 -- extension. There is no point in checking the ancestor type or
14405 -- the progenitors since the construct is wrong to begin with.
14407 if Ada_Version >= Ada_2005
14408 and then Is_Generic_Type (T)
14409 and then Present (Original_Node (N))
14412 Decl : constant Node_Id := Original_Node (N);
14415 if Nkind (Decl) = N_Formal_Type_Declaration
14416 and then Nkind (Formal_Type_Definition (Decl)) =
14417 N_Formal_Derived_Type_Definition
14418 and then Synchronized_Present (Formal_Type_Definition (Decl))
14419 and then No (Extension)
14421 -- Avoid emitting a duplicate error message
14423 and then not Error_Posted (Indic)
14426 ("synchronized derived type must have extension", N);
14431 if Null_Exclusion_Present (Def)
14432 and then not Is_Access_Type (Parent_Type)
14434 Error_Msg_N ("null exclusion can only apply to an access type", N);
14437 -- Avoid deriving parent primitives of underlying record views
14439 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
14440 Derive_Subps => not Is_Underlying_Record_View (T));
14442 -- AI-419: The parent type of an explicitly limited derived type must
14443 -- be a limited type or a limited interface.
14445 if Limited_Present (Def) then
14446 Set_Is_Limited_Record (T);
14448 if Is_Interface (T) then
14449 Set_Is_Limited_Interface (T);
14452 if not Is_Limited_Type (Parent_Type)
14454 (not Is_Interface (Parent_Type)
14455 or else not Is_Limited_Interface (Parent_Type))
14457 -- AI05-0096: a derivation in the private part of an instance is
14458 -- legal if the generic formal is untagged limited, and the actual
14461 if Is_Generic_Actual_Type (Parent_Type)
14462 and then In_Private_Part (Current_Scope)
14465 (Generic_Parent_Type (Parent (Parent_Type)))
14471 ("parent type& of limited type must be limited",
14477 -- In SPARK, there are no derived type definitions other than type
14478 -- extensions of tagged record types.
14480 if No (Extension) then
14481 Check_SPARK_Restriction ("derived type is not allowed", N);
14483 end Derived_Type_Declaration;
14485 ------------------------
14486 -- Diagnose_Interface --
14487 ------------------------
14489 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
14491 if not Is_Interface (E)
14492 and then E /= Any_Type
14494 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
14496 end Diagnose_Interface;
14498 ----------------------------------
14499 -- Enumeration_Type_Declaration --
14500 ----------------------------------
14502 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
14509 -- Create identifier node representing lower bound
14511 B_Node := New_Node (N_Identifier, Sloc (Def));
14512 L := First (Literals (Def));
14513 Set_Chars (B_Node, Chars (L));
14514 Set_Entity (B_Node, L);
14515 Set_Etype (B_Node, T);
14516 Set_Is_Static_Expression (B_Node, True);
14518 R_Node := New_Node (N_Range, Sloc (Def));
14519 Set_Low_Bound (R_Node, B_Node);
14521 Set_Ekind (T, E_Enumeration_Type);
14522 Set_First_Literal (T, L);
14524 Set_Is_Constrained (T);
14528 -- Loop through literals of enumeration type setting pos and rep values
14529 -- except that if the Ekind is already set, then it means the literal
14530 -- was already constructed (case of a derived type declaration and we
14531 -- should not disturb the Pos and Rep values.
14533 while Present (L) loop
14534 if Ekind (L) /= E_Enumeration_Literal then
14535 Set_Ekind (L, E_Enumeration_Literal);
14536 Set_Enumeration_Pos (L, Ev);
14537 Set_Enumeration_Rep (L, Ev);
14538 Set_Is_Known_Valid (L, True);
14542 New_Overloaded_Entity (L);
14543 Generate_Definition (L);
14544 Set_Convention (L, Convention_Intrinsic);
14546 -- Case of character literal
14548 if Nkind (L) = N_Defining_Character_Literal then
14549 Set_Is_Character_Type (T, True);
14551 -- Check violation of No_Wide_Characters
14553 if Restriction_Check_Required (No_Wide_Characters) then
14554 Get_Name_String (Chars (L));
14556 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
14557 Check_Restriction (No_Wide_Characters, L);
14566 -- Now create a node representing upper bound
14568 B_Node := New_Node (N_Identifier, Sloc (Def));
14569 Set_Chars (B_Node, Chars (Last (Literals (Def))));
14570 Set_Entity (B_Node, Last (Literals (Def)));
14571 Set_Etype (B_Node, T);
14572 Set_Is_Static_Expression (B_Node, True);
14574 Set_High_Bound (R_Node, B_Node);
14576 -- Initialize various fields of the type. Some of this information
14577 -- may be overwritten later through rep.clauses.
14579 Set_Scalar_Range (T, R_Node);
14580 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
14581 Set_Enum_Esize (T);
14582 Set_Enum_Pos_To_Rep (T, Empty);
14584 -- Enumeration type is in ALFA only if it is not a character type
14586 if not Is_Character_Type (T) then
14587 Set_Is_In_ALFA (T);
14590 -- Set Discard_Names if configuration pragma set, or if there is
14591 -- a parameterless pragma in the current declarative region
14593 if Global_Discard_Names
14594 or else Discard_Names (Scope (T))
14596 Set_Discard_Names (T);
14599 -- Process end label if there is one
14601 if Present (Def) then
14602 Process_End_Label (Def, 'e', T);
14604 end Enumeration_Type_Declaration;
14606 ---------------------------------
14607 -- Expand_To_Stored_Constraint --
14608 ---------------------------------
14610 function Expand_To_Stored_Constraint
14612 Constraint : Elist_Id) return Elist_Id
14614 Explicitly_Discriminated_Type : Entity_Id;
14615 Expansion : Elist_Id;
14616 Discriminant : Entity_Id;
14618 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
14619 -- Find the nearest type that actually specifies discriminants
14621 ---------------------------------
14622 -- Type_With_Explicit_Discrims --
14623 ---------------------------------
14625 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
14626 Typ : constant E := Base_Type (Id);
14629 if Ekind (Typ) in Incomplete_Or_Private_Kind then
14630 if Present (Full_View (Typ)) then
14631 return Type_With_Explicit_Discrims (Full_View (Typ));
14635 if Has_Discriminants (Typ) then
14640 if Etype (Typ) = Typ then
14642 elsif Has_Discriminants (Typ) then
14645 return Type_With_Explicit_Discrims (Etype (Typ));
14648 end Type_With_Explicit_Discrims;
14650 -- Start of processing for Expand_To_Stored_Constraint
14654 or else Is_Empty_Elmt_List (Constraint)
14659 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
14661 if No (Explicitly_Discriminated_Type) then
14665 Expansion := New_Elmt_List;
14668 First_Stored_Discriminant (Explicitly_Discriminated_Type);
14669 while Present (Discriminant) loop
14671 Get_Discriminant_Value (
14672 Discriminant, Explicitly_Discriminated_Type, Constraint),
14674 Next_Stored_Discriminant (Discriminant);
14678 end Expand_To_Stored_Constraint;
14680 ---------------------------
14681 -- Find_Hidden_Interface --
14682 ---------------------------
14684 function Find_Hidden_Interface
14686 Dest : Elist_Id) return Entity_Id
14689 Iface_Elmt : Elmt_Id;
14692 if Present (Src) and then Present (Dest) then
14693 Iface_Elmt := First_Elmt (Src);
14694 while Present (Iface_Elmt) loop
14695 Iface := Node (Iface_Elmt);
14697 if Is_Interface (Iface)
14698 and then not Contain_Interface (Iface, Dest)
14703 Next_Elmt (Iface_Elmt);
14708 end Find_Hidden_Interface;
14710 --------------------
14711 -- Find_Type_Name --
14712 --------------------
14714 function Find_Type_Name (N : Node_Id) return Entity_Id is
14715 Id : constant Entity_Id := Defining_Identifier (N);
14717 New_Id : Entity_Id;
14718 Prev_Par : Node_Id;
14720 procedure Tag_Mismatch;
14721 -- Diagnose a tagged partial view whose full view is untagged.
14722 -- We post the message on the full view, with a reference to
14723 -- the previous partial view. The partial view can be private
14724 -- or incomplete, and these are handled in a different manner,
14725 -- so we determine the position of the error message from the
14726 -- respective slocs of both.
14732 procedure Tag_Mismatch is
14734 if Sloc (Prev) < Sloc (Id) then
14735 if Ada_Version >= Ada_2012
14736 and then Nkind (N) = N_Private_Type_Declaration
14739 ("declaration of private } must be a tagged type ", Id, Prev);
14742 ("full declaration of } must be a tagged type ", Id, Prev);
14745 if Ada_Version >= Ada_2012
14746 and then Nkind (N) = N_Private_Type_Declaration
14749 ("declaration of private } must be a tagged type ", Prev, Id);
14752 ("full declaration of } must be a tagged type ", Prev, Id);
14757 -- Start of processing for Find_Type_Name
14760 -- Find incomplete declaration, if one was given
14762 Prev := Current_Entity_In_Scope (Id);
14764 -- New type declaration
14770 -- Previous declaration exists
14773 Prev_Par := Parent (Prev);
14775 -- Error if not incomplete/private case except if previous
14776 -- declaration is implicit, etc. Enter_Name will emit error if
14779 if not Is_Incomplete_Or_Private_Type (Prev) then
14783 -- Check invalid completion of private or incomplete type
14785 elsif not Nkind_In (N, N_Full_Type_Declaration,
14786 N_Task_Type_Declaration,
14787 N_Protected_Type_Declaration)
14789 (Ada_Version < Ada_2012
14790 or else not Is_Incomplete_Type (Prev)
14791 or else not Nkind_In (N, N_Private_Type_Declaration,
14792 N_Private_Extension_Declaration))
14794 -- Completion must be a full type declarations (RM 7.3(4))
14796 Error_Msg_Sloc := Sloc (Prev);
14797 Error_Msg_NE ("invalid completion of }", Id, Prev);
14799 -- Set scope of Id to avoid cascaded errors. Entity is never
14800 -- examined again, except when saving globals in generics.
14802 Set_Scope (Id, Current_Scope);
14805 -- If this is a repeated incomplete declaration, no further
14806 -- checks are possible.
14808 if Nkind (N) = N_Incomplete_Type_Declaration then
14812 -- Case of full declaration of incomplete type
14814 elsif Ekind (Prev) = E_Incomplete_Type
14815 and then (Ada_Version < Ada_2012
14816 or else No (Full_View (Prev))
14817 or else not Is_Private_Type (Full_View (Prev)))
14820 -- Indicate that the incomplete declaration has a matching full
14821 -- declaration. The defining occurrence of the incomplete
14822 -- declaration remains the visible one, and the procedure
14823 -- Get_Full_View dereferences it whenever the type is used.
14825 if Present (Full_View (Prev)) then
14826 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
14829 Set_Full_View (Prev, Id);
14830 Append_Entity (Id, Current_Scope);
14831 Set_Is_Public (Id, Is_Public (Prev));
14832 Set_Is_Internal (Id);
14835 -- If the incomplete view is tagged, a class_wide type has been
14836 -- created already. Use it for the private type as well, in order
14837 -- to prevent multiple incompatible class-wide types that may be
14838 -- created for self-referential anonymous access components.
14840 if Is_Tagged_Type (Prev)
14841 and then Present (Class_Wide_Type (Prev))
14843 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
14844 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
14845 Set_Etype (Class_Wide_Type (Id), Id);
14848 -- Case of full declaration of private type
14851 -- If the private type was a completion of an incomplete type then
14852 -- update Prev to reference the private type
14854 if Ada_Version >= Ada_2012
14855 and then Ekind (Prev) = E_Incomplete_Type
14856 and then Present (Full_View (Prev))
14857 and then Is_Private_Type (Full_View (Prev))
14859 Prev := Full_View (Prev);
14860 Prev_Par := Parent (Prev);
14863 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
14864 if Etype (Prev) /= Prev then
14866 -- Prev is a private subtype or a derived type, and needs
14869 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
14872 elsif Ekind (Prev) = E_Private_Type
14873 and then Nkind_In (N, N_Task_Type_Declaration,
14874 N_Protected_Type_Declaration)
14877 ("completion of nonlimited type cannot be limited", N);
14879 elsif Ekind (Prev) = E_Record_Type_With_Private
14880 and then Nkind_In (N, N_Task_Type_Declaration,
14881 N_Protected_Type_Declaration)
14883 if not Is_Limited_Record (Prev) then
14885 ("completion of nonlimited type cannot be limited", N);
14887 elsif No (Interface_List (N)) then
14889 ("completion of tagged private type must be tagged",
14893 elsif Nkind (N) = N_Full_Type_Declaration
14895 Nkind (Type_Definition (N)) = N_Record_Definition
14896 and then Interface_Present (Type_Definition (N))
14899 ("completion of private type cannot be an interface", N);
14902 -- Ada 2005 (AI-251): Private extension declaration of a task
14903 -- type or a protected type. This case arises when covering
14904 -- interface types.
14906 elsif Nkind_In (N, N_Task_Type_Declaration,
14907 N_Protected_Type_Declaration)
14911 elsif Nkind (N) /= N_Full_Type_Declaration
14912 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
14915 ("full view of private extension must be an extension", N);
14917 elsif not (Abstract_Present (Parent (Prev)))
14918 and then Abstract_Present (Type_Definition (N))
14921 ("full view of non-abstract extension cannot be abstract", N);
14924 if not In_Private_Part (Current_Scope) then
14926 ("declaration of full view must appear in private part", N);
14929 Copy_And_Swap (Prev, Id);
14930 Set_Has_Private_Declaration (Prev);
14931 Set_Has_Private_Declaration (Id);
14933 -- If no error, propagate freeze_node from private to full view.
14934 -- It may have been generated for an early operational item.
14936 if Present (Freeze_Node (Id))
14937 and then Serious_Errors_Detected = 0
14938 and then No (Full_View (Id))
14940 Set_Freeze_Node (Prev, Freeze_Node (Id));
14941 Set_Freeze_Node (Id, Empty);
14942 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
14945 Set_Full_View (Id, Prev);
14949 -- Verify that full declaration conforms to partial one
14951 if Is_Incomplete_Or_Private_Type (Prev)
14952 and then Present (Discriminant_Specifications (Prev_Par))
14954 if Present (Discriminant_Specifications (N)) then
14955 if Ekind (Prev) = E_Incomplete_Type then
14956 Check_Discriminant_Conformance (N, Prev, Prev);
14958 Check_Discriminant_Conformance (N, Prev, Id);
14963 ("missing discriminants in full type declaration", N);
14965 -- To avoid cascaded errors on subsequent use, share the
14966 -- discriminants of the partial view.
14968 Set_Discriminant_Specifications (N,
14969 Discriminant_Specifications (Prev_Par));
14973 -- A prior untagged partial view can have an associated class-wide
14974 -- type due to use of the class attribute, and in this case the full
14975 -- type must also be tagged. This Ada 95 usage is deprecated in favor
14976 -- of incomplete tagged declarations, but we check for it.
14979 and then (Is_Tagged_Type (Prev)
14980 or else Present (Class_Wide_Type (Prev)))
14982 -- Ada 2012 (AI05-0162): A private type may be the completion of
14983 -- an incomplete type
14985 if Ada_Version >= Ada_2012
14986 and then Is_Incomplete_Type (Prev)
14987 and then Nkind_In (N, N_Private_Type_Declaration,
14988 N_Private_Extension_Declaration)
14990 -- No need to check private extensions since they are tagged
14992 if Nkind (N) = N_Private_Type_Declaration
14993 and then not Tagged_Present (N)
14998 -- The full declaration is either a tagged type (including
14999 -- a synchronized type that implements interfaces) or a
15000 -- type extension, otherwise this is an error.
15002 elsif Nkind_In (N, N_Task_Type_Declaration,
15003 N_Protected_Type_Declaration)
15005 if No (Interface_List (N))
15006 and then not Error_Posted (N)
15011 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
15013 -- Indicate that the previous declaration (tagged incomplete
15014 -- or private declaration) requires the same on the full one.
15016 if not Tagged_Present (Type_Definition (N)) then
15018 Set_Is_Tagged_Type (Id);
15021 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
15022 if No (Record_Extension_Part (Type_Definition (N))) then
15024 ("full declaration of } must be a record extension",
15027 -- Set some attributes to produce a usable full view
15029 Set_Is_Tagged_Type (Id);
15039 end Find_Type_Name;
15041 -------------------------
15042 -- Find_Type_Of_Object --
15043 -------------------------
15045 function Find_Type_Of_Object
15046 (Obj_Def : Node_Id;
15047 Related_Nod : Node_Id) return Entity_Id
15049 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
15050 P : Node_Id := Parent (Obj_Def);
15055 -- If the parent is a component_definition node we climb to the
15056 -- component_declaration node
15058 if Nkind (P) = N_Component_Definition then
15062 -- Case of an anonymous array subtype
15064 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
15065 N_Unconstrained_Array_Definition)
15068 Array_Type_Declaration (T, Obj_Def);
15070 -- Create an explicit subtype whenever possible
15072 elsif Nkind (P) /= N_Component_Declaration
15073 and then Def_Kind = N_Subtype_Indication
15075 -- Base name of subtype on object name, which will be unique in
15076 -- the current scope.
15078 -- If this is a duplicate declaration, return base type, to avoid
15079 -- generating duplicate anonymous types.
15081 if Error_Posted (P) then
15082 Analyze (Subtype_Mark (Obj_Def));
15083 return Entity (Subtype_Mark (Obj_Def));
15088 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
15090 T := Make_Defining_Identifier (Sloc (P), Nam);
15092 Insert_Action (Obj_Def,
15093 Make_Subtype_Declaration (Sloc (P),
15094 Defining_Identifier => T,
15095 Subtype_Indication => Relocate_Node (Obj_Def)));
15097 -- This subtype may need freezing, and this will not be done
15098 -- automatically if the object declaration is not in declarative
15099 -- part. Since this is an object declaration, the type cannot always
15100 -- be frozen here. Deferred constants do not freeze their type
15101 -- (which often enough will be private).
15103 if Nkind (P) = N_Object_Declaration
15104 and then Constant_Present (P)
15105 and then No (Expression (P))
15109 Insert_Actions (Obj_Def, Freeze_Entity (T, P));
15112 -- Ada 2005 AI-406: the object definition in an object declaration
15113 -- can be an access definition.
15115 elsif Def_Kind = N_Access_Definition then
15116 T := Access_Definition (Related_Nod, Obj_Def);
15117 Set_Is_Local_Anonymous_Access (T);
15119 -- Otherwise, the object definition is just a subtype_mark
15122 T := Process_Subtype (Obj_Def, Related_Nod);
15124 -- If expansion is disabled an object definition that is an aggregate
15125 -- will not get expanded and may lead to scoping problems in the back
15126 -- end, if the object is referenced in an inner scope. In that case
15127 -- create an itype reference for the object definition now. This
15128 -- may be redundant in some cases, but harmless.
15131 and then Nkind (Related_Nod) = N_Object_Declaration
15134 Build_Itype_Reference (T, Related_Nod);
15139 end Find_Type_Of_Object;
15141 --------------------------------
15142 -- Find_Type_Of_Subtype_Indic --
15143 --------------------------------
15145 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
15149 -- Case of subtype mark with a constraint
15151 if Nkind (S) = N_Subtype_Indication then
15152 Find_Type (Subtype_Mark (S));
15153 Typ := Entity (Subtype_Mark (S));
15156 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
15159 ("incorrect constraint for this kind of type", Constraint (S));
15160 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
15163 -- Otherwise we have a subtype mark without a constraint
15165 elsif Error_Posted (S) then
15166 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
15174 -- Check No_Wide_Characters restriction
15176 Check_Wide_Character_Restriction (Typ, S);
15179 end Find_Type_Of_Subtype_Indic;
15181 -------------------------------------
15182 -- Floating_Point_Type_Declaration --
15183 -------------------------------------
15185 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
15186 Digs : constant Node_Id := Digits_Expression (Def);
15187 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
15189 Base_Typ : Entity_Id;
15190 Implicit_Base : Entity_Id;
15193 function Can_Derive_From (E : Entity_Id) return Boolean;
15194 -- Find if given digits value, and possibly a specified range, allows
15195 -- derivation from specified type
15197 function Find_Base_Type return Entity_Id;
15198 -- Find a predefined base type that Def can derive from, or generate
15199 -- an error and substitute Long_Long_Float if none exists.
15201 ---------------------
15202 -- Can_Derive_From --
15203 ---------------------
15205 function Can_Derive_From (E : Entity_Id) return Boolean is
15206 Spec : constant Entity_Id := Real_Range_Specification (Def);
15209 if Digs_Val > Digits_Value (E) then
15213 if Present (Spec) then
15214 if Expr_Value_R (Type_Low_Bound (E)) >
15215 Expr_Value_R (Low_Bound (Spec))
15220 if Expr_Value_R (Type_High_Bound (E)) <
15221 Expr_Value_R (High_Bound (Spec))
15228 end Can_Derive_From;
15230 --------------------
15231 -- Find_Base_Type --
15232 --------------------
15234 function Find_Base_Type return Entity_Id is
15235 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
15238 -- Iterate over the predefined types in order, returning the first
15239 -- one that Def can derive from.
15241 while Present (Choice) loop
15242 if Can_Derive_From (Node (Choice)) then
15243 return Node (Choice);
15246 Next_Elmt (Choice);
15249 -- If we can't derive from any existing type, use Long_Long_Float
15250 -- and give appropriate message explaining the problem.
15252 if Digs_Val > Max_Digs_Val then
15253 -- It might be the case that there is a type with the requested
15254 -- range, just not the combination of digits and range.
15257 ("no predefined type has requested range and precision",
15258 Real_Range_Specification (Def));
15262 ("range too large for any predefined type",
15263 Real_Range_Specification (Def));
15266 return Standard_Long_Long_Float;
15267 end Find_Base_Type;
15269 -- Start of processing for Floating_Point_Type_Declaration
15272 Check_Restriction (No_Floating_Point, Def);
15274 -- Create an implicit base type
15277 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
15279 -- Analyze and verify digits value
15281 Analyze_And_Resolve (Digs, Any_Integer);
15282 Check_Digits_Expression (Digs);
15283 Digs_Val := Expr_Value (Digs);
15285 -- Process possible range spec and find correct type to derive from
15287 Process_Real_Range_Specification (Def);
15289 -- Check that requested number of digits is not too high.
15291 if Digs_Val > Max_Digs_Val then
15292 -- The check for Max_Base_Digits may be somewhat expensive, as it
15293 -- requires reading System, so only do it when necessary.
15296 Max_Base_Digits : constant Uint :=
15299 (Parent (RTE (RE_Max_Base_Digits))));
15302 if Digs_Val > Max_Base_Digits then
15303 Error_Msg_Uint_1 := Max_Base_Digits;
15304 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
15306 elsif No (Real_Range_Specification (Def)) then
15307 Error_Msg_Uint_1 := Max_Digs_Val;
15308 Error_Msg_N ("types with more than ^ digits need range spec "
15309 & "('R'M 3.5.7(6))", Digs);
15314 -- Find a suitable type to derive from or complain and use a substitute
15316 Base_Typ := Find_Base_Type;
15318 -- If there are bounds given in the declaration use them as the bounds
15319 -- of the type, otherwise use the bounds of the predefined base type
15320 -- that was chosen based on the Digits value.
15322 if Present (Real_Range_Specification (Def)) then
15323 Set_Scalar_Range (T, Real_Range_Specification (Def));
15324 Set_Is_Constrained (T);
15326 -- The bounds of this range must be converted to machine numbers
15327 -- in accordance with RM 4.9(38).
15329 Bound := Type_Low_Bound (T);
15331 if Nkind (Bound) = N_Real_Literal then
15333 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
15334 Set_Is_Machine_Number (Bound);
15337 Bound := Type_High_Bound (T);
15339 if Nkind (Bound) = N_Real_Literal then
15341 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
15342 Set_Is_Machine_Number (Bound);
15346 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
15349 -- Complete definition of implicit base and declared first subtype
15351 Set_Etype (Implicit_Base, Base_Typ);
15353 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
15354 Set_Size_Info (Implicit_Base, (Base_Typ));
15355 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
15356 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
15357 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
15358 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
15360 Set_Ekind (T, E_Floating_Point_Subtype);
15361 Set_Etype (T, Implicit_Base);
15363 Set_Size_Info (T, (Implicit_Base));
15364 Set_RM_Size (T, RM_Size (Implicit_Base));
15365 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
15366 Set_Digits_Value (T, Digs_Val);
15367 end Floating_Point_Type_Declaration;
15369 ----------------------------
15370 -- Get_Discriminant_Value --
15371 ----------------------------
15373 -- This is the situation:
15375 -- There is a non-derived type
15377 -- type T0 (Dx, Dy, Dz...)
15379 -- There are zero or more levels of derivation, with each derivation
15380 -- either purely inheriting the discriminants, or defining its own.
15382 -- type Ti is new Ti-1
15384 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
15386 -- subtype Ti is ...
15388 -- The subtype issue is avoided by the use of Original_Record_Component,
15389 -- and the fact that derived subtypes also derive the constraints.
15391 -- This chain leads back from
15393 -- Typ_For_Constraint
15395 -- Typ_For_Constraint has discriminants, and the value for each
15396 -- discriminant is given by its corresponding Elmt of Constraints.
15398 -- Discriminant is some discriminant in this hierarchy
15400 -- We need to return its value
15402 -- We do this by recursively searching each level, and looking for
15403 -- Discriminant. Once we get to the bottom, we start backing up
15404 -- returning the value for it which may in turn be a discriminant
15405 -- further up, so on the backup we continue the substitution.
15407 function Get_Discriminant_Value
15408 (Discriminant : Entity_Id;
15409 Typ_For_Constraint : Entity_Id;
15410 Constraint : Elist_Id) return Node_Id
15412 function Search_Derivation_Levels
15414 Discrim_Values : Elist_Id;
15415 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
15416 -- This is the routine that performs the recursive search of levels
15417 -- as described above.
15419 ------------------------------
15420 -- Search_Derivation_Levels --
15421 ------------------------------
15423 function Search_Derivation_Levels
15425 Discrim_Values : Elist_Id;
15426 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
15430 Result : Node_Or_Entity_Id;
15431 Result_Entity : Node_Id;
15434 -- If inappropriate type, return Error, this happens only in
15435 -- cascaded error situations, and we want to avoid a blow up.
15437 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
15441 -- Look deeper if possible. Use Stored_Constraints only for
15442 -- untagged types. For tagged types use the given constraint.
15443 -- This asymmetry needs explanation???
15445 if not Stored_Discrim_Values
15446 and then Present (Stored_Constraint (Ti))
15447 and then not Is_Tagged_Type (Ti)
15450 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
15453 Td : constant Entity_Id := Etype (Ti);
15457 Result := Discriminant;
15460 if Present (Stored_Constraint (Ti)) then
15462 Search_Derivation_Levels
15463 (Td, Stored_Constraint (Ti), True);
15466 Search_Derivation_Levels
15467 (Td, Discrim_Values, Stored_Discrim_Values);
15473 -- Extra underlying places to search, if not found above. For
15474 -- concurrent types, the relevant discriminant appears in the
15475 -- corresponding record. For a type derived from a private type
15476 -- without discriminant, the full view inherits the discriminants
15477 -- of the full view of the parent.
15479 if Result = Discriminant then
15480 if Is_Concurrent_Type (Ti)
15481 and then Present (Corresponding_Record_Type (Ti))
15484 Search_Derivation_Levels (
15485 Corresponding_Record_Type (Ti),
15487 Stored_Discrim_Values);
15489 elsif Is_Private_Type (Ti)
15490 and then not Has_Discriminants (Ti)
15491 and then Present (Full_View (Ti))
15492 and then Etype (Full_View (Ti)) /= Ti
15495 Search_Derivation_Levels (
15498 Stored_Discrim_Values);
15502 -- If Result is not a (reference to a) discriminant, return it,
15503 -- otherwise set Result_Entity to the discriminant.
15505 if Nkind (Result) = N_Defining_Identifier then
15506 pragma Assert (Result = Discriminant);
15507 Result_Entity := Result;
15510 if not Denotes_Discriminant (Result) then
15514 Result_Entity := Entity (Result);
15517 -- See if this level of derivation actually has discriminants
15518 -- because tagged derivations can add them, hence the lower
15519 -- levels need not have any.
15521 if not Has_Discriminants (Ti) then
15525 -- Scan Ti's discriminants for Result_Entity,
15526 -- and return its corresponding value, if any.
15528 Result_Entity := Original_Record_Component (Result_Entity);
15530 Assoc := First_Elmt (Discrim_Values);
15532 if Stored_Discrim_Values then
15533 Disc := First_Stored_Discriminant (Ti);
15535 Disc := First_Discriminant (Ti);
15538 while Present (Disc) loop
15539 pragma Assert (Present (Assoc));
15541 if Original_Record_Component (Disc) = Result_Entity then
15542 return Node (Assoc);
15547 if Stored_Discrim_Values then
15548 Next_Stored_Discriminant (Disc);
15550 Next_Discriminant (Disc);
15554 -- Could not find it
15557 end Search_Derivation_Levels;
15561 Result : Node_Or_Entity_Id;
15563 -- Start of processing for Get_Discriminant_Value
15566 -- ??? This routine is a gigantic mess and will be deleted. For the
15567 -- time being just test for the trivial case before calling recurse.
15569 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
15575 D := First_Discriminant (Typ_For_Constraint);
15576 E := First_Elmt (Constraint);
15577 while Present (D) loop
15578 if Chars (D) = Chars (Discriminant) then
15582 Next_Discriminant (D);
15588 Result := Search_Derivation_Levels
15589 (Typ_For_Constraint, Constraint, False);
15591 -- ??? hack to disappear when this routine is gone
15593 if Nkind (Result) = N_Defining_Identifier then
15599 D := First_Discriminant (Typ_For_Constraint);
15600 E := First_Elmt (Constraint);
15601 while Present (D) loop
15602 if Corresponding_Discriminant (D) = Discriminant then
15606 Next_Discriminant (D);
15612 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
15614 end Get_Discriminant_Value;
15616 --------------------------
15617 -- Has_Range_Constraint --
15618 --------------------------
15620 function Has_Range_Constraint (N : Node_Id) return Boolean is
15621 C : constant Node_Id := Constraint (N);
15624 if Nkind (C) = N_Range_Constraint then
15627 elsif Nkind (C) = N_Digits_Constraint then
15629 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
15631 Present (Range_Constraint (C));
15633 elsif Nkind (C) = N_Delta_Constraint then
15634 return Present (Range_Constraint (C));
15639 end Has_Range_Constraint;
15641 ------------------------
15642 -- Inherit_Components --
15643 ------------------------
15645 function Inherit_Components
15647 Parent_Base : Entity_Id;
15648 Derived_Base : Entity_Id;
15649 Is_Tagged : Boolean;
15650 Inherit_Discr : Boolean;
15651 Discs : Elist_Id) return Elist_Id
15653 Assoc_List : constant Elist_Id := New_Elmt_List;
15655 procedure Inherit_Component
15656 (Old_C : Entity_Id;
15657 Plain_Discrim : Boolean := False;
15658 Stored_Discrim : Boolean := False);
15659 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
15660 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
15661 -- True, Old_C is a stored discriminant. If they are both false then
15662 -- Old_C is a regular component.
15664 -----------------------
15665 -- Inherit_Component --
15666 -----------------------
15668 procedure Inherit_Component
15669 (Old_C : Entity_Id;
15670 Plain_Discrim : Boolean := False;
15671 Stored_Discrim : Boolean := False)
15673 New_C : constant Entity_Id := New_Copy (Old_C);
15675 Discrim : Entity_Id;
15676 Corr_Discrim : Entity_Id;
15679 pragma Assert (not Is_Tagged or else not Stored_Discrim);
15681 Set_Parent (New_C, Parent (Old_C));
15683 -- Regular discriminants and components must be inserted in the scope
15684 -- of the Derived_Base. Do it here.
15686 if not Stored_Discrim then
15687 Enter_Name (New_C);
15690 -- For tagged types the Original_Record_Component must point to
15691 -- whatever this field was pointing to in the parent type. This has
15692 -- already been achieved by the call to New_Copy above.
15694 if not Is_Tagged then
15695 Set_Original_Record_Component (New_C, New_C);
15698 -- If we have inherited a component then see if its Etype contains
15699 -- references to Parent_Base discriminants. In this case, replace
15700 -- these references with the constraints given in Discs. We do not
15701 -- do this for the partial view of private types because this is
15702 -- not needed (only the components of the full view will be used
15703 -- for code generation) and cause problem. We also avoid this
15704 -- transformation in some error situations.
15706 if Ekind (New_C) = E_Component then
15707 if (Is_Private_Type (Derived_Base)
15708 and then not Is_Generic_Type (Derived_Base))
15709 or else (Is_Empty_Elmt_List (Discs)
15710 and then not Expander_Active)
15712 Set_Etype (New_C, Etype (Old_C));
15715 -- The current component introduces a circularity of the
15718 -- limited with Pack_2;
15719 -- package Pack_1 is
15720 -- type T_1 is tagged record
15721 -- Comp : access Pack_2.T_2;
15727 -- package Pack_2 is
15728 -- type T_2 is new Pack_1.T_1 with ...;
15733 Constrain_Component_Type
15734 (Old_C, Derived_Base, N, Parent_Base, Discs));
15738 -- In derived tagged types it is illegal to reference a non
15739 -- discriminant component in the parent type. To catch this, mark
15740 -- these components with an Ekind of E_Void. This will be reset in
15741 -- Record_Type_Definition after processing the record extension of
15742 -- the derived type.
15744 -- If the declaration is a private extension, there is no further
15745 -- record extension to process, and the components retain their
15746 -- current kind, because they are visible at this point.
15748 if Is_Tagged and then Ekind (New_C) = E_Component
15749 and then Nkind (N) /= N_Private_Extension_Declaration
15751 Set_Ekind (New_C, E_Void);
15754 if Plain_Discrim then
15755 Set_Corresponding_Discriminant (New_C, Old_C);
15756 Build_Discriminal (New_C);
15758 -- If we are explicitly inheriting a stored discriminant it will be
15759 -- completely hidden.
15761 elsif Stored_Discrim then
15762 Set_Corresponding_Discriminant (New_C, Empty);
15763 Set_Discriminal (New_C, Empty);
15764 Set_Is_Completely_Hidden (New_C);
15766 -- Set the Original_Record_Component of each discriminant in the
15767 -- derived base to point to the corresponding stored that we just
15770 Discrim := First_Discriminant (Derived_Base);
15771 while Present (Discrim) loop
15772 Corr_Discrim := Corresponding_Discriminant (Discrim);
15774 -- Corr_Discrim could be missing in an error situation
15776 if Present (Corr_Discrim)
15777 and then Original_Record_Component (Corr_Discrim) = Old_C
15779 Set_Original_Record_Component (Discrim, New_C);
15782 Next_Discriminant (Discrim);
15785 Append_Entity (New_C, Derived_Base);
15788 if not Is_Tagged then
15789 Append_Elmt (Old_C, Assoc_List);
15790 Append_Elmt (New_C, Assoc_List);
15792 end Inherit_Component;
15794 -- Variables local to Inherit_Component
15796 Loc : constant Source_Ptr := Sloc (N);
15798 Parent_Discrim : Entity_Id;
15799 Stored_Discrim : Entity_Id;
15801 Component : Entity_Id;
15803 -- Start of processing for Inherit_Components
15806 if not Is_Tagged then
15807 Append_Elmt (Parent_Base, Assoc_List);
15808 Append_Elmt (Derived_Base, Assoc_List);
15811 -- Inherit parent discriminants if needed
15813 if Inherit_Discr then
15814 Parent_Discrim := First_Discriminant (Parent_Base);
15815 while Present (Parent_Discrim) loop
15816 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
15817 Next_Discriminant (Parent_Discrim);
15821 -- Create explicit stored discrims for untagged types when necessary
15823 if not Has_Unknown_Discriminants (Derived_Base)
15824 and then Has_Discriminants (Parent_Base)
15825 and then not Is_Tagged
15828 or else First_Discriminant (Parent_Base) /=
15829 First_Stored_Discriminant (Parent_Base))
15831 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
15832 while Present (Stored_Discrim) loop
15833 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
15834 Next_Stored_Discriminant (Stored_Discrim);
15838 -- See if we can apply the second transformation for derived types, as
15839 -- explained in point 6. in the comments above Build_Derived_Record_Type
15840 -- This is achieved by appending Derived_Base discriminants into Discs,
15841 -- which has the side effect of returning a non empty Discs list to the
15842 -- caller of Inherit_Components, which is what we want. This must be
15843 -- done for private derived types if there are explicit stored
15844 -- discriminants, to ensure that we can retrieve the values of the
15845 -- constraints provided in the ancestors.
15848 and then Is_Empty_Elmt_List (Discs)
15849 and then Present (First_Discriminant (Derived_Base))
15851 (not Is_Private_Type (Derived_Base)
15852 or else Is_Completely_Hidden
15853 (First_Stored_Discriminant (Derived_Base))
15854 or else Is_Generic_Type (Derived_Base))
15856 D := First_Discriminant (Derived_Base);
15857 while Present (D) loop
15858 Append_Elmt (New_Reference_To (D, Loc), Discs);
15859 Next_Discriminant (D);
15863 -- Finally, inherit non-discriminant components unless they are not
15864 -- visible because defined or inherited from the full view of the
15865 -- parent. Don't inherit the _parent field of the parent type.
15867 Component := First_Entity (Parent_Base);
15868 while Present (Component) loop
15870 -- Ada 2005 (AI-251): Do not inherit components associated with
15871 -- secondary tags of the parent.
15873 if Ekind (Component) = E_Component
15874 and then Present (Related_Type (Component))
15878 elsif Ekind (Component) /= E_Component
15879 or else Chars (Component) = Name_uParent
15883 -- If the derived type is within the parent type's declarative
15884 -- region, then the components can still be inherited even though
15885 -- they aren't visible at this point. This can occur for cases
15886 -- such as within public child units where the components must
15887 -- become visible upon entering the child unit's private part.
15889 elsif not Is_Visible_Component (Component)
15890 and then not In_Open_Scopes (Scope (Parent_Base))
15894 elsif Ekind_In (Derived_Base, E_Private_Type,
15895 E_Limited_Private_Type)
15900 Inherit_Component (Component);
15903 Next_Entity (Component);
15906 -- For tagged derived types, inherited discriminants cannot be used in
15907 -- component declarations of the record extension part. To achieve this
15908 -- we mark the inherited discriminants as not visible.
15910 if Is_Tagged and then Inherit_Discr then
15911 D := First_Discriminant (Derived_Base);
15912 while Present (D) loop
15913 Set_Is_Immediately_Visible (D, False);
15914 Next_Discriminant (D);
15919 end Inherit_Components;
15921 -----------------------
15922 -- Is_Constant_Bound --
15923 -----------------------
15925 function Is_Constant_Bound (Exp : Node_Id) return Boolean is
15927 if Compile_Time_Known_Value (Exp) then
15930 elsif Is_Entity_Name (Exp)
15931 and then Present (Entity (Exp))
15933 return Is_Constant_Object (Entity (Exp))
15934 or else Ekind (Entity (Exp)) = E_Enumeration_Literal;
15936 elsif Nkind (Exp) in N_Binary_Op then
15937 return Is_Constant_Bound (Left_Opnd (Exp))
15938 and then Is_Constant_Bound (Right_Opnd (Exp))
15939 and then Scope (Entity (Exp)) = Standard_Standard;
15944 end Is_Constant_Bound;
15946 -----------------------
15947 -- Is_Null_Extension --
15948 -----------------------
15950 function Is_Null_Extension (T : Entity_Id) return Boolean is
15951 Type_Decl : constant Node_Id := Parent (Base_Type (T));
15952 Comp_List : Node_Id;
15956 if Nkind (Type_Decl) /= N_Full_Type_Declaration
15957 or else not Is_Tagged_Type (T)
15958 or else Nkind (Type_Definition (Type_Decl)) /=
15959 N_Derived_Type_Definition
15960 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
15966 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
15968 if Present (Discriminant_Specifications (Type_Decl)) then
15971 elsif Present (Comp_List)
15972 and then Is_Non_Empty_List (Component_Items (Comp_List))
15974 Comp := First (Component_Items (Comp_List));
15976 -- Only user-defined components are relevant. The component list
15977 -- may also contain a parent component and internal components
15978 -- corresponding to secondary tags, but these do not determine
15979 -- whether this is a null extension.
15981 while Present (Comp) loop
15982 if Comes_From_Source (Comp) then
15993 end Is_Null_Extension;
15995 ------------------------------
15996 -- Is_Valid_Constraint_Kind --
15997 ------------------------------
15999 function Is_Valid_Constraint_Kind
16000 (T_Kind : Type_Kind;
16001 Constraint_Kind : Node_Kind) return Boolean
16005 when Enumeration_Kind |
16007 return Constraint_Kind = N_Range_Constraint;
16009 when Decimal_Fixed_Point_Kind =>
16010 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
16011 N_Range_Constraint);
16013 when Ordinary_Fixed_Point_Kind =>
16014 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
16015 N_Range_Constraint);
16018 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
16019 N_Range_Constraint);
16026 E_Incomplete_Type |
16029 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
16032 return True; -- Error will be detected later
16034 end Is_Valid_Constraint_Kind;
16036 --------------------------
16037 -- Is_Visible_Component --
16038 --------------------------
16040 function Is_Visible_Component (C : Entity_Id) return Boolean is
16041 Original_Comp : Entity_Id := Empty;
16042 Original_Scope : Entity_Id;
16043 Type_Scope : Entity_Id;
16045 function Is_Local_Type (Typ : Entity_Id) return Boolean;
16046 -- Check whether parent type of inherited component is declared locally,
16047 -- possibly within a nested package or instance. The current scope is
16048 -- the derived record itself.
16050 -------------------
16051 -- Is_Local_Type --
16052 -------------------
16054 function Is_Local_Type (Typ : Entity_Id) return Boolean is
16058 Scop := Scope (Typ);
16059 while Present (Scop)
16060 and then Scop /= Standard_Standard
16062 if Scop = Scope (Current_Scope) then
16066 Scop := Scope (Scop);
16072 -- Start of processing for Is_Visible_Component
16075 if Ekind_In (C, E_Component, E_Discriminant) then
16076 Original_Comp := Original_Record_Component (C);
16079 if No (Original_Comp) then
16081 -- Premature usage, or previous error
16086 Original_Scope := Scope (Original_Comp);
16087 Type_Scope := Scope (Base_Type (Scope (C)));
16090 -- This test only concerns tagged types
16092 if not Is_Tagged_Type (Original_Scope) then
16095 -- If it is _Parent or _Tag, there is no visibility issue
16097 elsif not Comes_From_Source (Original_Comp) then
16100 -- If we are in the body of an instantiation, the component is visible
16101 -- even when the parent type (possibly defined in an enclosing unit or
16102 -- in a parent unit) might not.
16104 elsif In_Instance_Body then
16107 -- Discriminants are always visible
16109 elsif Ekind (Original_Comp) = E_Discriminant
16110 and then not Has_Unknown_Discriminants (Original_Scope)
16114 -- If the component has been declared in an ancestor which is currently
16115 -- a private type, then it is not visible. The same applies if the
16116 -- component's containing type is not in an open scope and the original
16117 -- component's enclosing type is a visible full view of a private type
16118 -- (which can occur in cases where an attempt is being made to reference
16119 -- a component in a sibling package that is inherited from a visible
16120 -- component of a type in an ancestor package; the component in the
16121 -- sibling package should not be visible even though the component it
16122 -- inherited from is visible). This does not apply however in the case
16123 -- where the scope of the type is a private child unit, or when the
16124 -- parent comes from a local package in which the ancestor is currently
16125 -- visible. The latter suppression of visibility is needed for cases
16126 -- that are tested in B730006.
16128 elsif Is_Private_Type (Original_Scope)
16130 (not Is_Private_Descendant (Type_Scope)
16131 and then not In_Open_Scopes (Type_Scope)
16132 and then Has_Private_Declaration (Original_Scope))
16134 -- If the type derives from an entity in a formal package, there
16135 -- are no additional visible components.
16137 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
16138 N_Formal_Package_Declaration
16142 -- if we are not in the private part of the current package, there
16143 -- are no additional visible components.
16145 elsif Ekind (Scope (Current_Scope)) = E_Package
16146 and then not In_Private_Part (Scope (Current_Scope))
16151 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
16152 and then In_Open_Scopes (Scope (Original_Scope))
16153 and then Is_Local_Type (Type_Scope);
16156 -- There is another weird way in which a component may be invisible
16157 -- when the private and the full view are not derived from the same
16158 -- ancestor. Here is an example :
16160 -- type A1 is tagged record F1 : integer; end record;
16161 -- type A2 is new A1 with record F2 : integer; end record;
16162 -- type T is new A1 with private;
16164 -- type T is new A2 with null record;
16166 -- In this case, the full view of T inherits F1 and F2 but the private
16167 -- view inherits only F1
16171 Ancestor : Entity_Id := Scope (C);
16175 if Ancestor = Original_Scope then
16177 elsif Ancestor = Etype (Ancestor) then
16181 Ancestor := Etype (Ancestor);
16185 end Is_Visible_Component;
16187 --------------------------
16188 -- Make_Class_Wide_Type --
16189 --------------------------
16191 procedure Make_Class_Wide_Type (T : Entity_Id) is
16192 CW_Type : Entity_Id;
16194 Next_E : Entity_Id;
16197 if Present (Class_Wide_Type (T)) then
16199 -- The class-wide type is a partially decorated entity created for a
16200 -- unanalyzed tagged type referenced through a limited with clause.
16201 -- When the tagged type is analyzed, its class-wide type needs to be
16202 -- redecorated. Note that we reuse the entity created by Decorate_
16203 -- Tagged_Type in order to preserve all links.
16205 if Materialize_Entity (Class_Wide_Type (T)) then
16206 CW_Type := Class_Wide_Type (T);
16207 Set_Materialize_Entity (CW_Type, False);
16209 -- The class wide type can have been defined by the partial view, in
16210 -- which case everything is already done.
16216 -- Default case, we need to create a new class-wide type
16220 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
16223 -- Inherit root type characteristics
16225 CW_Name := Chars (CW_Type);
16226 Next_E := Next_Entity (CW_Type);
16227 Copy_Node (T, CW_Type);
16228 Set_Comes_From_Source (CW_Type, False);
16229 Set_Chars (CW_Type, CW_Name);
16230 Set_Parent (CW_Type, Parent (T));
16231 Set_Next_Entity (CW_Type, Next_E);
16233 -- Ensure we have a new freeze node for the class-wide type. The partial
16234 -- view may have freeze action of its own, requiring a proper freeze
16235 -- node, and the same freeze node cannot be shared between the two
16238 Set_Has_Delayed_Freeze (CW_Type);
16239 Set_Freeze_Node (CW_Type, Empty);
16241 -- Customize the class-wide type: It has no prim. op., it cannot be
16242 -- abstract and its Etype points back to the specific root type.
16244 Set_Ekind (CW_Type, E_Class_Wide_Type);
16245 Set_Is_Tagged_Type (CW_Type, True);
16246 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
16247 Set_Is_Abstract_Type (CW_Type, False);
16248 Set_Is_Constrained (CW_Type, False);
16249 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
16251 if Ekind (T) = E_Class_Wide_Subtype then
16252 Set_Etype (CW_Type, Etype (Base_Type (T)));
16254 Set_Etype (CW_Type, T);
16257 -- If this is the class_wide type of a constrained subtype, it does
16258 -- not have discriminants.
16260 Set_Has_Discriminants (CW_Type,
16261 Has_Discriminants (T) and then not Is_Constrained (T));
16263 Set_Has_Unknown_Discriminants (CW_Type, True);
16264 Set_Class_Wide_Type (T, CW_Type);
16265 Set_Equivalent_Type (CW_Type, Empty);
16267 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
16269 Set_Class_Wide_Type (CW_Type, CW_Type);
16270 end Make_Class_Wide_Type;
16276 procedure Make_Index
16278 Related_Nod : Node_Id;
16279 Related_Id : Entity_Id := Empty;
16280 Suffix_Index : Nat := 1;
16281 In_Iter_Schm : Boolean := False)
16285 Def_Id : Entity_Id := Empty;
16286 Found : Boolean := False;
16289 -- For a discrete range used in a constrained array definition and
16290 -- defined by a range, an implicit conversion to the predefined type
16291 -- INTEGER is assumed if each bound is either a numeric literal, a named
16292 -- number, or an attribute, and the type of both bounds (prior to the
16293 -- implicit conversion) is the type universal_integer. Otherwise, both
16294 -- bounds must be of the same discrete type, other than universal
16295 -- integer; this type must be determinable independently of the
16296 -- context, but using the fact that the type must be discrete and that
16297 -- both bounds must have the same type.
16299 -- Character literals also have a universal type in the absence of
16300 -- of additional context, and are resolved to Standard_Character.
16302 if Nkind (I) = N_Range then
16304 -- The index is given by a range constraint. The bounds are known
16305 -- to be of a consistent type.
16307 if not Is_Overloaded (I) then
16310 -- For universal bounds, choose the specific predefined type
16312 if T = Universal_Integer then
16313 T := Standard_Integer;
16315 elsif T = Any_Character then
16316 Ambiguous_Character (Low_Bound (I));
16318 T := Standard_Character;
16321 -- The node may be overloaded because some user-defined operators
16322 -- are available, but if a universal interpretation exists it is
16323 -- also the selected one.
16325 elsif Universal_Interpretation (I) = Universal_Integer then
16326 T := Standard_Integer;
16332 Ind : Interp_Index;
16336 Get_First_Interp (I, Ind, It);
16337 while Present (It.Typ) loop
16338 if Is_Discrete_Type (It.Typ) then
16341 and then not Covers (It.Typ, T)
16342 and then not Covers (T, It.Typ)
16344 Error_Msg_N ("ambiguous bounds in discrete range", I);
16352 Get_Next_Interp (Ind, It);
16355 if T = Any_Type then
16356 Error_Msg_N ("discrete type required for range", I);
16357 Set_Etype (I, Any_Type);
16360 elsif T = Universal_Integer then
16361 T := Standard_Integer;
16366 if not Is_Discrete_Type (T) then
16367 Error_Msg_N ("discrete type required for range", I);
16368 Set_Etype (I, Any_Type);
16372 if Nkind (Low_Bound (I)) = N_Attribute_Reference
16373 and then Attribute_Name (Low_Bound (I)) = Name_First
16374 and then Is_Entity_Name (Prefix (Low_Bound (I)))
16375 and then Is_Type (Entity (Prefix (Low_Bound (I))))
16376 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (I))))
16378 -- The type of the index will be the type of the prefix, as long
16379 -- as the upper bound is 'Last of the same type.
16381 Def_Id := Entity (Prefix (Low_Bound (I)));
16383 if Nkind (High_Bound (I)) /= N_Attribute_Reference
16384 or else Attribute_Name (High_Bound (I)) /= Name_Last
16385 or else not Is_Entity_Name (Prefix (High_Bound (I)))
16386 or else Entity (Prefix (High_Bound (I))) /= Def_Id
16393 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
16395 elsif Nkind (I) = N_Subtype_Indication then
16397 -- The index is given by a subtype with a range constraint
16399 T := Base_Type (Entity (Subtype_Mark (I)));
16401 if not Is_Discrete_Type (T) then
16402 Error_Msg_N ("discrete type required for range", I);
16403 Set_Etype (I, Any_Type);
16407 R := Range_Expression (Constraint (I));
16410 Process_Range_Expr_In_Decl
16411 (R, Entity (Subtype_Mark (I)), In_Iter_Schm => In_Iter_Schm);
16413 elsif Nkind (I) = N_Attribute_Reference then
16415 -- The parser guarantees that the attribute is a RANGE attribute
16417 -- If the node denotes the range of a type mark, that is also the
16418 -- resulting type, and we do no need to create an Itype for it.
16420 if Is_Entity_Name (Prefix (I))
16421 and then Comes_From_Source (I)
16422 and then Is_Type (Entity (Prefix (I)))
16423 and then Is_Discrete_Type (Entity (Prefix (I)))
16425 Def_Id := Entity (Prefix (I));
16428 Analyze_And_Resolve (I);
16432 -- If none of the above, must be a subtype. We convert this to a
16433 -- range attribute reference because in the case of declared first
16434 -- named subtypes, the types in the range reference can be different
16435 -- from the type of the entity. A range attribute normalizes the
16436 -- reference and obtains the correct types for the bounds.
16438 -- This transformation is in the nature of an expansion, is only
16439 -- done if expansion is active. In particular, it is not done on
16440 -- formal generic types, because we need to retain the name of the
16441 -- original index for instantiation purposes.
16444 if not Is_Entity_Name (I) or else not Is_Type (Entity (I)) then
16445 Error_Msg_N ("invalid subtype mark in discrete range ", I);
16446 Set_Etype (I, Any_Integer);
16450 -- The type mark may be that of an incomplete type. It is only
16451 -- now that we can get the full view, previous analysis does
16452 -- not look specifically for a type mark.
16454 Set_Entity (I, Get_Full_View (Entity (I)));
16455 Set_Etype (I, Entity (I));
16456 Def_Id := Entity (I);
16458 if not Is_Discrete_Type (Def_Id) then
16459 Error_Msg_N ("discrete type required for index", I);
16460 Set_Etype (I, Any_Type);
16465 if Expander_Active then
16467 Make_Attribute_Reference (Sloc (I),
16468 Attribute_Name => Name_Range,
16469 Prefix => Relocate_Node (I)));
16471 -- The original was a subtype mark that does not freeze. This
16472 -- means that the rewritten version must not freeze either.
16474 Set_Must_Not_Freeze (I);
16475 Set_Must_Not_Freeze (Prefix (I));
16477 -- Is order critical??? if so, document why, if not
16478 -- use Analyze_And_Resolve
16480 Analyze_And_Resolve (I);
16484 -- If expander is inactive, type is legal, nothing else to construct
16491 if not Is_Discrete_Type (T) then
16492 Error_Msg_N ("discrete type required for range", I);
16493 Set_Etype (I, Any_Type);
16496 elsif T = Any_Type then
16497 Set_Etype (I, Any_Type);
16501 -- We will now create the appropriate Itype to describe the range, but
16502 -- first a check. If we originally had a subtype, then we just label
16503 -- the range with this subtype. Not only is there no need to construct
16504 -- a new subtype, but it is wrong to do so for two reasons:
16506 -- 1. A legality concern, if we have a subtype, it must not freeze,
16507 -- and the Itype would cause freezing incorrectly
16509 -- 2. An efficiency concern, if we created an Itype, it would not be
16510 -- recognized as the same type for the purposes of eliminating
16511 -- checks in some circumstances.
16513 -- We signal this case by setting the subtype entity in Def_Id
16515 if No (Def_Id) then
16517 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
16518 Set_Etype (Def_Id, Base_Type (T));
16520 if Is_Signed_Integer_Type (T) then
16521 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
16523 elsif Is_Modular_Integer_Type (T) then
16524 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
16527 Set_Ekind (Def_Id, E_Enumeration_Subtype);
16528 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
16529 Set_First_Literal (Def_Id, First_Literal (T));
16532 Set_Size_Info (Def_Id, (T));
16533 Set_RM_Size (Def_Id, RM_Size (T));
16534 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
16536 Set_Scalar_Range (Def_Id, R);
16537 Conditional_Delay (Def_Id, T);
16539 -- In the subtype indication case, if the immediate parent of the
16540 -- new subtype is non-static, then the subtype we create is non-
16541 -- static, even if its bounds are static.
16543 if Nkind (I) = N_Subtype_Indication
16544 and then not Is_Static_Subtype (Entity (Subtype_Mark (I)))
16546 Set_Is_Non_Static_Subtype (Def_Id);
16550 -- Final step is to label the index with this constructed type
16552 Set_Etype (I, Def_Id);
16555 ------------------------------
16556 -- Modular_Type_Declaration --
16557 ------------------------------
16559 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16560 Mod_Expr : constant Node_Id := Expression (Def);
16563 procedure Set_Modular_Size (Bits : Int);
16564 -- Sets RM_Size to Bits, and Esize to normal word size above this
16566 ----------------------
16567 -- Set_Modular_Size --
16568 ----------------------
16570 procedure Set_Modular_Size (Bits : Int) is
16572 Set_RM_Size (T, UI_From_Int (Bits));
16577 elsif Bits <= 16 then
16578 Init_Esize (T, 16);
16580 elsif Bits <= 32 then
16581 Init_Esize (T, 32);
16584 Init_Esize (T, System_Max_Binary_Modulus_Power);
16587 if not Non_Binary_Modulus (T)
16588 and then Esize (T) = RM_Size (T)
16590 Set_Is_Known_Valid (T);
16592 end Set_Modular_Size;
16594 -- Start of processing for Modular_Type_Declaration
16597 Analyze_And_Resolve (Mod_Expr, Any_Integer);
16599 Set_Ekind (T, E_Modular_Integer_Type);
16600 Init_Alignment (T);
16601 Set_Is_Constrained (T);
16603 if not Is_OK_Static_Expression (Mod_Expr) then
16604 Flag_Non_Static_Expr
16605 ("non-static expression used for modular type bound!", Mod_Expr);
16606 M_Val := 2 ** System_Max_Binary_Modulus_Power;
16608 M_Val := Expr_Value (Mod_Expr);
16612 Error_Msg_N ("modulus value must be positive", Mod_Expr);
16613 M_Val := 2 ** System_Max_Binary_Modulus_Power;
16616 Set_Modulus (T, M_Val);
16618 -- Create bounds for the modular type based on the modulus given in
16619 -- the type declaration and then analyze and resolve those bounds.
16621 Set_Scalar_Range (T,
16622 Make_Range (Sloc (Mod_Expr),
16623 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
16624 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
16626 -- Properly analyze the literals for the range. We do this manually
16627 -- because we can't go calling Resolve, since we are resolving these
16628 -- bounds with the type, and this type is certainly not complete yet!
16630 Set_Etype (Low_Bound (Scalar_Range (T)), T);
16631 Set_Etype (High_Bound (Scalar_Range (T)), T);
16632 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
16633 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
16635 -- Loop through powers of two to find number of bits required
16637 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
16641 if M_Val = 2 ** Bits then
16642 Set_Modular_Size (Bits);
16647 elsif M_Val < 2 ** Bits then
16648 Check_SPARK_Restriction ("modulus should be a power of 2", T);
16649 Set_Non_Binary_Modulus (T);
16651 if Bits > System_Max_Nonbinary_Modulus_Power then
16652 Error_Msg_Uint_1 :=
16653 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
16655 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
16656 Set_Modular_Size (System_Max_Binary_Modulus_Power);
16660 -- In the non-binary case, set size as per RM 13.3(55)
16662 Set_Modular_Size (Bits);
16669 -- If we fall through, then the size exceed System.Max_Binary_Modulus
16670 -- so we just signal an error and set the maximum size.
16672 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
16673 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
16675 Set_Modular_Size (System_Max_Binary_Modulus_Power);
16676 Init_Alignment (T);
16678 end Modular_Type_Declaration;
16680 --------------------------
16681 -- New_Concatenation_Op --
16682 --------------------------
16684 procedure New_Concatenation_Op (Typ : Entity_Id) is
16685 Loc : constant Source_Ptr := Sloc (Typ);
16688 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
16689 -- Create abbreviated declaration for the formal of a predefined
16690 -- Operator 'Op' of type 'Typ'
16692 --------------------
16693 -- Make_Op_Formal --
16694 --------------------
16696 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
16697 Formal : Entity_Id;
16699 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
16700 Set_Etype (Formal, Typ);
16701 Set_Mechanism (Formal, Default_Mechanism);
16703 end Make_Op_Formal;
16705 -- Start of processing for New_Concatenation_Op
16708 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
16710 Set_Ekind (Op, E_Operator);
16711 Set_Scope (Op, Current_Scope);
16712 Set_Etype (Op, Typ);
16713 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
16714 Set_Is_Immediately_Visible (Op);
16715 Set_Is_Intrinsic_Subprogram (Op);
16716 Set_Has_Completion (Op);
16717 Append_Entity (Op, Current_Scope);
16719 Set_Name_Entity_Id (Name_Op_Concat, Op);
16721 Append_Entity (Make_Op_Formal (Typ, Op), Op);
16722 Append_Entity (Make_Op_Formal (Typ, Op), Op);
16723 end New_Concatenation_Op;
16725 -------------------------
16726 -- OK_For_Limited_Init --
16727 -------------------------
16729 -- ???Check all calls of this, and compare the conditions under which it's
16732 function OK_For_Limited_Init
16734 Exp : Node_Id) return Boolean
16737 return Is_CPP_Constructor_Call (Exp)
16738 or else (Ada_Version >= Ada_2005
16739 and then not Debug_Flag_Dot_L
16740 and then OK_For_Limited_Init_In_05 (Typ, Exp));
16741 end OK_For_Limited_Init;
16743 -------------------------------
16744 -- OK_For_Limited_Init_In_05 --
16745 -------------------------------
16747 function OK_For_Limited_Init_In_05
16749 Exp : Node_Id) return Boolean
16752 -- An object of a limited interface type can be initialized with any
16753 -- expression of a nonlimited descendant type.
16755 if Is_Class_Wide_Type (Typ)
16756 and then Is_Limited_Interface (Typ)
16757 and then not Is_Limited_Type (Etype (Exp))
16762 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
16763 -- case of limited aggregates (including extension aggregates), and
16764 -- function calls. The function call may have been given in prefixed
16765 -- notation, in which case the original node is an indexed component.
16766 -- If the function is parameterless, the original node was an explicit
16769 case Nkind (Original_Node (Exp)) is
16770 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
16773 when N_Qualified_Expression =>
16775 OK_For_Limited_Init_In_05
16776 (Typ, Expression (Original_Node (Exp)));
16778 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
16779 -- with a function call, the expander has rewritten the call into an
16780 -- N_Type_Conversion node to force displacement of the pointer to
16781 -- reference the component containing the secondary dispatch table.
16782 -- Otherwise a type conversion is not a legal context.
16783 -- A return statement for a build-in-place function returning a
16784 -- synchronized type also introduces an unchecked conversion.
16786 when N_Type_Conversion |
16787 N_Unchecked_Type_Conversion =>
16788 return not Comes_From_Source (Exp)
16790 OK_For_Limited_Init_In_05
16791 (Typ, Expression (Original_Node (Exp)));
16793 when N_Indexed_Component |
16794 N_Selected_Component |
16795 N_Explicit_Dereference =>
16796 return Nkind (Exp) = N_Function_Call;
16798 -- A use of 'Input is a function call, hence allowed. Normally the
16799 -- attribute will be changed to a call, but the attribute by itself
16800 -- can occur with -gnatc.
16802 when N_Attribute_Reference =>
16803 return Attribute_Name (Original_Node (Exp)) = Name_Input;
16808 end OK_For_Limited_Init_In_05;
16810 -------------------------------------------
16811 -- Ordinary_Fixed_Point_Type_Declaration --
16812 -------------------------------------------
16814 procedure Ordinary_Fixed_Point_Type_Declaration
16818 Loc : constant Source_Ptr := Sloc (Def);
16819 Delta_Expr : constant Node_Id := Delta_Expression (Def);
16820 RRS : constant Node_Id := Real_Range_Specification (Def);
16821 Implicit_Base : Entity_Id;
16828 Check_Restriction (No_Fixed_Point, Def);
16830 -- Create implicit base type
16833 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
16834 Set_Etype (Implicit_Base, Implicit_Base);
16836 -- Analyze and process delta expression
16838 Analyze_And_Resolve (Delta_Expr, Any_Real);
16840 Check_Delta_Expression (Delta_Expr);
16841 Delta_Val := Expr_Value_R (Delta_Expr);
16843 Set_Delta_Value (Implicit_Base, Delta_Val);
16845 -- Compute default small from given delta, which is the largest power
16846 -- of two that does not exceed the given delta value.
16856 if Delta_Val < Ureal_1 then
16857 while Delta_Val < Tmp loop
16858 Tmp := Tmp / Ureal_2;
16859 Scale := Scale + 1;
16864 Tmp := Tmp * Ureal_2;
16865 exit when Tmp > Delta_Val;
16866 Scale := Scale - 1;
16870 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
16873 Set_Small_Value (Implicit_Base, Small_Val);
16875 -- If no range was given, set a dummy range
16877 if RRS <= Empty_Or_Error then
16878 Low_Val := -Small_Val;
16879 High_Val := Small_Val;
16881 -- Otherwise analyze and process given range
16885 Low : constant Node_Id := Low_Bound (RRS);
16886 High : constant Node_Id := High_Bound (RRS);
16889 Analyze_And_Resolve (Low, Any_Real);
16890 Analyze_And_Resolve (High, Any_Real);
16891 Check_Real_Bound (Low);
16892 Check_Real_Bound (High);
16894 -- Obtain and set the range
16896 Low_Val := Expr_Value_R (Low);
16897 High_Val := Expr_Value_R (High);
16899 if Low_Val > High_Val then
16900 Error_Msg_NE ("?fixed point type& has null range", Def, T);
16905 -- The range for both the implicit base and the declared first subtype
16906 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
16907 -- set a temporary range in place. Note that the bounds of the base
16908 -- type will be widened to be symmetrical and to fill the available
16909 -- bits when the type is frozen.
16911 -- We could do this with all discrete types, and probably should, but
16912 -- we absolutely have to do it for fixed-point, since the end-points
16913 -- of the range and the size are determined by the small value, which
16914 -- could be reset before the freeze point.
16916 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
16917 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
16919 -- Complete definition of first subtype
16921 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
16922 Set_Etype (T, Implicit_Base);
16923 Init_Size_Align (T);
16924 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
16925 Set_Small_Value (T, Small_Val);
16926 Set_Delta_Value (T, Delta_Val);
16927 Set_Is_Constrained (T);
16929 end Ordinary_Fixed_Point_Type_Declaration;
16931 ----------------------------------------
16932 -- Prepare_Private_Subtype_Completion --
16933 ----------------------------------------
16935 procedure Prepare_Private_Subtype_Completion
16937 Related_Nod : Node_Id)
16939 Id_B : constant Entity_Id := Base_Type (Id);
16940 Full_B : constant Entity_Id := Full_View (Id_B);
16944 if Present (Full_B) then
16946 -- The Base_Type is already completed, we can complete the subtype
16947 -- now. We have to create a new entity with the same name, Thus we
16948 -- can't use Create_Itype.
16950 -- This is messy, should be fixed ???
16952 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
16953 Set_Is_Itype (Full);
16954 Set_Associated_Node_For_Itype (Full, Related_Nod);
16955 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
16958 -- The parent subtype may be private, but the base might not, in some
16959 -- nested instances. In that case, the subtype does not need to be
16960 -- exchanged. It would still be nice to make private subtypes and their
16961 -- bases consistent at all times ???
16963 if Is_Private_Type (Id_B) then
16964 Append_Elmt (Id, Private_Dependents (Id_B));
16967 end Prepare_Private_Subtype_Completion;
16969 ---------------------------
16970 -- Process_Discriminants --
16971 ---------------------------
16973 procedure Process_Discriminants
16975 Prev : Entity_Id := Empty)
16977 Elist : constant Elist_Id := New_Elmt_List;
16980 Discr_Number : Uint;
16981 Discr_Type : Entity_Id;
16982 Default_Present : Boolean := False;
16983 Default_Not_Present : Boolean := False;
16986 -- A composite type other than an array type can have discriminants.
16987 -- On entry, the current scope is the composite type.
16989 -- The discriminants are initially entered into the scope of the type
16990 -- via Enter_Name with the default Ekind of E_Void to prevent premature
16991 -- use, as explained at the end of this procedure.
16993 Discr := First (Discriminant_Specifications (N));
16994 while Present (Discr) loop
16995 Enter_Name (Defining_Identifier (Discr));
16997 -- For navigation purposes we add a reference to the discriminant
16998 -- in the entity for the type. If the current declaration is a
16999 -- completion, place references on the partial view. Otherwise the
17000 -- type is the current scope.
17002 if Present (Prev) then
17004 -- The references go on the partial view, if present. If the
17005 -- partial view has discriminants, the references have been
17006 -- generated already.
17008 if not Has_Discriminants (Prev) then
17009 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
17013 (Current_Scope, Defining_Identifier (Discr), 'd');
17016 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
17017 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
17019 -- Ada 2005 (AI-254)
17021 if Present (Access_To_Subprogram_Definition
17022 (Discriminant_Type (Discr)))
17023 and then Protected_Present (Access_To_Subprogram_Definition
17024 (Discriminant_Type (Discr)))
17027 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
17031 Find_Type (Discriminant_Type (Discr));
17032 Discr_Type := Etype (Discriminant_Type (Discr));
17034 if Error_Posted (Discriminant_Type (Discr)) then
17035 Discr_Type := Any_Type;
17039 if Is_Access_Type (Discr_Type) then
17041 -- Ada 2005 (AI-230): Access discriminant allowed in non-limited
17044 if Ada_Version < Ada_2005 then
17045 Check_Access_Discriminant_Requires_Limited
17046 (Discr, Discriminant_Type (Discr));
17049 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
17051 ("(Ada 83) access discriminant not allowed", Discr);
17054 elsif not Is_Discrete_Type (Discr_Type) then
17055 Error_Msg_N ("discriminants must have a discrete or access type",
17056 Discriminant_Type (Discr));
17059 Set_Etype (Defining_Identifier (Discr), Discr_Type);
17061 -- If a discriminant specification includes the assignment compound
17062 -- delimiter followed by an expression, the expression is the default
17063 -- expression of the discriminant; the default expression must be of
17064 -- the type of the discriminant. (RM 3.7.1) Since this expression is
17065 -- a default expression, we do the special preanalysis, since this
17066 -- expression does not freeze (see "Handling of Default and Per-
17067 -- Object Expressions" in spec of package Sem).
17069 if Present (Expression (Discr)) then
17070 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
17072 if Nkind (N) = N_Formal_Type_Declaration then
17074 ("discriminant defaults not allowed for formal type",
17075 Expression (Discr));
17077 -- Flag an error for a tagged type with defaulted discriminants,
17078 -- excluding limited tagged types when compiling for Ada 2012
17079 -- (see AI05-0214).
17081 elsif Is_Tagged_Type (Current_Scope)
17082 and then (not Is_Limited_Type (Current_Scope)
17083 or else Ada_Version < Ada_2012)
17084 and then Comes_From_Source (N)
17086 -- Note: see similar test in Check_Or_Process_Discriminants, to
17087 -- handle the (illegal) case of the completion of an untagged
17088 -- view with discriminants with defaults by a tagged full view.
17089 -- We skip the check if Discr does not come from source, to
17090 -- account for the case of an untagged derived type providing
17091 -- defaults for a renamed discriminant from a private untagged
17092 -- ancestor with a tagged full view (ACATS B460006).
17094 if Ada_Version >= Ada_2012 then
17096 ("discriminants of nonlimited tagged type cannot have"
17098 Expression (Discr));
17101 ("discriminants of tagged type cannot have defaults",
17102 Expression (Discr));
17106 Default_Present := True;
17107 Append_Elmt (Expression (Discr), Elist);
17109 -- Tag the defining identifiers for the discriminants with
17110 -- their corresponding default expressions from the tree.
17112 Set_Discriminant_Default_Value
17113 (Defining_Identifier (Discr), Expression (Discr));
17117 Default_Not_Present := True;
17120 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
17121 -- Discr_Type but with the null-exclusion attribute
17123 if Ada_Version >= Ada_2005 then
17125 -- Ada 2005 (AI-231): Static checks
17127 if Can_Never_Be_Null (Discr_Type) then
17128 Null_Exclusion_Static_Checks (Discr);
17130 elsif Is_Access_Type (Discr_Type)
17131 and then Null_Exclusion_Present (Discr)
17133 -- No need to check itypes because in their case this check
17134 -- was done at their point of creation
17136 and then not Is_Itype (Discr_Type)
17138 if Can_Never_Be_Null (Discr_Type) then
17140 ("`NOT NULL` not allowed (& already excludes null)",
17145 Set_Etype (Defining_Identifier (Discr),
17146 Create_Null_Excluding_Itype
17148 Related_Nod => Discr));
17150 -- Check for improper null exclusion if the type is otherwise
17151 -- legal for a discriminant.
17153 elsif Null_Exclusion_Present (Discr)
17154 and then Is_Discrete_Type (Discr_Type)
17157 ("null exclusion can only apply to an access type", Discr);
17160 -- Ada 2005 (AI-402): access discriminants of nonlimited types
17161 -- can't have defaults. Synchronized types, or types that are
17162 -- explicitly limited are fine, but special tests apply to derived
17163 -- types in generics: in a generic body we have to assume the
17164 -- worst, and therefore defaults are not allowed if the parent is
17165 -- a generic formal private type (see ACATS B370001).
17167 if Is_Access_Type (Discr_Type) then
17168 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
17169 or else not Default_Present
17170 or else Is_Limited_Record (Current_Scope)
17171 or else Is_Concurrent_Type (Current_Scope)
17172 or else Is_Concurrent_Record_Type (Current_Scope)
17173 or else Ekind (Current_Scope) = E_Limited_Private_Type
17175 if not Is_Derived_Type (Current_Scope)
17176 or else not Is_Generic_Type (Etype (Current_Scope))
17177 or else not In_Package_Body (Scope (Etype (Current_Scope)))
17178 or else Limited_Present
17179 (Type_Definition (Parent (Current_Scope)))
17184 Error_Msg_N ("access discriminants of nonlimited types",
17185 Expression (Discr));
17186 Error_Msg_N ("\cannot have defaults", Expression (Discr));
17189 elsif Present (Expression (Discr)) then
17191 ("(Ada 2005) access discriminants of nonlimited types",
17192 Expression (Discr));
17193 Error_Msg_N ("\cannot have defaults", Expression (Discr));
17201 -- An element list consisting of the default expressions of the
17202 -- discriminants is constructed in the above loop and used to set
17203 -- the Discriminant_Constraint attribute for the type. If an object
17204 -- is declared of this (record or task) type without any explicit
17205 -- discriminant constraint given, this element list will form the
17206 -- actual parameters for the corresponding initialization procedure
17209 Set_Discriminant_Constraint (Current_Scope, Elist);
17210 Set_Stored_Constraint (Current_Scope, No_Elist);
17212 -- Default expressions must be provided either for all or for none
17213 -- of the discriminants of a discriminant part. (RM 3.7.1)
17215 if Default_Present and then Default_Not_Present then
17217 ("incomplete specification of defaults for discriminants", N);
17220 -- The use of the name of a discriminant is not allowed in default
17221 -- expressions of a discriminant part if the specification of the
17222 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
17224 -- To detect this, the discriminant names are entered initially with an
17225 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
17226 -- attempt to use a void entity (for example in an expression that is
17227 -- type-checked) produces the error message: premature usage. Now after
17228 -- completing the semantic analysis of the discriminant part, we can set
17229 -- the Ekind of all the discriminants appropriately.
17231 Discr := First (Discriminant_Specifications (N));
17232 Discr_Number := Uint_1;
17233 while Present (Discr) loop
17234 Id := Defining_Identifier (Discr);
17235 Set_Ekind (Id, E_Discriminant);
17236 Init_Component_Location (Id);
17238 Set_Discriminant_Number (Id, Discr_Number);
17240 -- Make sure this is always set, even in illegal programs
17242 Set_Corresponding_Discriminant (Id, Empty);
17244 -- Initialize the Original_Record_Component to the entity itself.
17245 -- Inherit_Components will propagate the right value to
17246 -- discriminants in derived record types.
17248 Set_Original_Record_Component (Id, Id);
17250 -- Create the discriminal for the discriminant
17252 Build_Discriminal (Id);
17255 Discr_Number := Discr_Number + 1;
17258 Set_Has_Discriminants (Current_Scope);
17259 end Process_Discriminants;
17261 -----------------------
17262 -- Process_Full_View --
17263 -----------------------
17265 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
17266 Priv_Parent : Entity_Id;
17267 Full_Parent : Entity_Id;
17268 Full_Indic : Node_Id;
17270 procedure Collect_Implemented_Interfaces
17272 Ifaces : Elist_Id);
17273 -- Ada 2005: Gather all the interfaces that Typ directly or
17274 -- inherently implements. Duplicate entries are not added to
17275 -- the list Ifaces.
17277 ------------------------------------
17278 -- Collect_Implemented_Interfaces --
17279 ------------------------------------
17281 procedure Collect_Implemented_Interfaces
17286 Iface_Elmt : Elmt_Id;
17289 -- Abstract interfaces are only associated with tagged record types
17291 if not Is_Tagged_Type (Typ)
17292 or else not Is_Record_Type (Typ)
17297 -- Recursively climb to the ancestors
17299 if Etype (Typ) /= Typ
17301 -- Protect the frontend against wrong cyclic declarations like:
17303 -- type B is new A with private;
17304 -- type C is new A with private;
17306 -- type B is new C with null record;
17307 -- type C is new B with null record;
17309 and then Etype (Typ) /= Priv_T
17310 and then Etype (Typ) /= Full_T
17312 -- Keep separate the management of private type declarations
17314 if Ekind (Typ) = E_Record_Type_With_Private then
17316 -- Handle the following erroneous case:
17317 -- type Private_Type is tagged private;
17319 -- type Private_Type is new Type_Implementing_Iface;
17321 if Present (Full_View (Typ))
17322 and then Etype (Typ) /= Full_View (Typ)
17324 if Is_Interface (Etype (Typ)) then
17325 Append_Unique_Elmt (Etype (Typ), Ifaces);
17328 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
17331 -- Non-private types
17334 if Is_Interface (Etype (Typ)) then
17335 Append_Unique_Elmt (Etype (Typ), Ifaces);
17338 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
17342 -- Handle entities in the list of abstract interfaces
17344 if Present (Interfaces (Typ)) then
17345 Iface_Elmt := First_Elmt (Interfaces (Typ));
17346 while Present (Iface_Elmt) loop
17347 Iface := Node (Iface_Elmt);
17349 pragma Assert (Is_Interface (Iface));
17351 if not Contain_Interface (Iface, Ifaces) then
17352 Append_Elmt (Iface, Ifaces);
17353 Collect_Implemented_Interfaces (Iface, Ifaces);
17356 Next_Elmt (Iface_Elmt);
17359 end Collect_Implemented_Interfaces;
17361 -- Start of processing for Process_Full_View
17364 -- First some sanity checks that must be done after semantic
17365 -- decoration of the full view and thus cannot be placed with other
17366 -- similar checks in Find_Type_Name
17368 if not Is_Limited_Type (Priv_T)
17369 and then (Is_Limited_Type (Full_T)
17370 or else Is_Limited_Composite (Full_T))
17373 ("completion of nonlimited type cannot be limited", Full_T);
17374 Explain_Limited_Type (Full_T, Full_T);
17376 elsif Is_Abstract_Type (Full_T)
17377 and then not Is_Abstract_Type (Priv_T)
17380 ("completion of nonabstract type cannot be abstract", Full_T);
17382 elsif Is_Tagged_Type (Priv_T)
17383 and then Is_Limited_Type (Priv_T)
17384 and then not Is_Limited_Type (Full_T)
17386 -- If pragma CPP_Class was applied to the private declaration
17387 -- propagate the limitedness to the full-view
17389 if Is_CPP_Class (Priv_T) then
17390 Set_Is_Limited_Record (Full_T);
17392 -- GNAT allow its own definition of Limited_Controlled to disobey
17393 -- this rule in order in ease the implementation. This test is safe
17394 -- because Root_Controlled is defined in a private system child.
17396 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
17397 Set_Is_Limited_Composite (Full_T);
17400 ("completion of limited tagged type must be limited", Full_T);
17403 elsif Is_Generic_Type (Priv_T) then
17404 Error_Msg_N ("generic type cannot have a completion", Full_T);
17407 -- Check that ancestor interfaces of private and full views are
17408 -- consistent. We omit this check for synchronized types because
17409 -- they are performed on the corresponding record type when frozen.
17411 if Ada_Version >= Ada_2005
17412 and then Is_Tagged_Type (Priv_T)
17413 and then Is_Tagged_Type (Full_T)
17414 and then not Is_Concurrent_Type (Full_T)
17418 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
17419 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
17422 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
17423 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
17425 -- Ada 2005 (AI-251): The partial view shall be a descendant of
17426 -- an interface type if and only if the full type is descendant
17427 -- of the interface type (AARM 7.3 (7.3/2).
17429 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
17431 if Present (Iface) then
17433 ("interface & not implemented by full type " &
17434 "(RM-2005 7.3 (7.3/2))", Priv_T, Iface);
17437 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
17439 if Present (Iface) then
17441 ("interface & not implemented by partial view " &
17442 "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
17447 if Is_Tagged_Type (Priv_T)
17448 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
17449 and then Is_Derived_Type (Full_T)
17451 Priv_Parent := Etype (Priv_T);
17453 -- The full view of a private extension may have been transformed
17454 -- into an unconstrained derived type declaration and a subtype
17455 -- declaration (see build_derived_record_type for details).
17457 if Nkind (N) = N_Subtype_Declaration then
17458 Full_Indic := Subtype_Indication (N);
17459 Full_Parent := Etype (Base_Type (Full_T));
17461 Full_Indic := Subtype_Indication (Type_Definition (N));
17462 Full_Parent := Etype (Full_T);
17465 -- Check that the parent type of the full type is a descendant of
17466 -- the ancestor subtype given in the private extension. If either
17467 -- entity has an Etype equal to Any_Type then we had some previous
17468 -- error situation [7.3(8)].
17470 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
17473 -- Ada 2005 (AI-251): Interfaces in the full-typ can be given in
17474 -- any order. Therefore we don't have to check that its parent must
17475 -- be a descendant of the parent of the private type declaration.
17477 elsif Is_Interface (Priv_Parent)
17478 and then Is_Interface (Full_Parent)
17482 -- Ada 2005 (AI-251): If the parent of the private type declaration
17483 -- is an interface there is no need to check that it is an ancestor
17484 -- of the associated full type declaration. The required tests for
17485 -- this case are performed by Build_Derived_Record_Type.
17487 elsif not Is_Interface (Base_Type (Priv_Parent))
17488 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
17491 ("parent of full type must descend from parent"
17492 & " of private extension", Full_Indic);
17494 -- First check a formal restriction, and then proceed with checking
17495 -- Ada rules. Since the formal restriction is not a serious error, we
17496 -- don't prevent further error detection for this check, hence the
17501 -- In formal mode, when completing a private extension the type
17502 -- named in the private part must be exactly the same as that
17503 -- named in the visible part.
17505 if Priv_Parent /= Full_Parent then
17506 Error_Msg_Name_1 := Chars (Priv_Parent);
17507 Check_SPARK_Restriction ("% expected", Full_Indic);
17510 -- Check the rules of 7.3(10): if the private extension inherits
17511 -- known discriminants, then the full type must also inherit those
17512 -- discriminants from the same (ancestor) type, and the parent
17513 -- subtype of the full type must be constrained if and only if
17514 -- the ancestor subtype of the private extension is constrained.
17516 if No (Discriminant_Specifications (Parent (Priv_T)))
17517 and then not Has_Unknown_Discriminants (Priv_T)
17518 and then Has_Discriminants (Base_Type (Priv_Parent))
17521 Priv_Indic : constant Node_Id :=
17522 Subtype_Indication (Parent (Priv_T));
17524 Priv_Constr : constant Boolean :=
17525 Is_Constrained (Priv_Parent)
17527 Nkind (Priv_Indic) = N_Subtype_Indication
17529 Is_Constrained (Entity (Priv_Indic));
17531 Full_Constr : constant Boolean :=
17532 Is_Constrained (Full_Parent)
17534 Nkind (Full_Indic) = N_Subtype_Indication
17536 Is_Constrained (Entity (Full_Indic));
17538 Priv_Discr : Entity_Id;
17539 Full_Discr : Entity_Id;
17542 Priv_Discr := First_Discriminant (Priv_Parent);
17543 Full_Discr := First_Discriminant (Full_Parent);
17544 while Present (Priv_Discr) and then Present (Full_Discr) loop
17545 if Original_Record_Component (Priv_Discr) =
17546 Original_Record_Component (Full_Discr)
17548 Corresponding_Discriminant (Priv_Discr) =
17549 Corresponding_Discriminant (Full_Discr)
17556 Next_Discriminant (Priv_Discr);
17557 Next_Discriminant (Full_Discr);
17560 if Present (Priv_Discr) or else Present (Full_Discr) then
17562 ("full view must inherit discriminants of the parent"
17563 & " type used in the private extension", Full_Indic);
17565 elsif Priv_Constr and then not Full_Constr then
17567 ("parent subtype of full type must be constrained",
17570 elsif Full_Constr and then not Priv_Constr then
17572 ("parent subtype of full type must be unconstrained",
17577 -- Check the rules of 7.3(12): if a partial view has neither
17578 -- known or unknown discriminants, then the full type
17579 -- declaration shall define a definite subtype.
17581 elsif not Has_Unknown_Discriminants (Priv_T)
17582 and then not Has_Discriminants (Priv_T)
17583 and then not Is_Constrained (Full_T)
17586 ("full view must define a constrained type if partial view"
17587 & " has no discriminants", Full_T);
17590 -- ??????? Do we implement the following properly ?????
17591 -- If the ancestor subtype of a private extension has constrained
17592 -- discriminants, then the parent subtype of the full view shall
17593 -- impose a statically matching constraint on those discriminants
17598 -- For untagged types, verify that a type without discriminants
17599 -- is not completed with an unconstrained type.
17601 if not Is_Indefinite_Subtype (Priv_T)
17602 and then Is_Indefinite_Subtype (Full_T)
17604 Error_Msg_N ("full view of type must be definite subtype", Full_T);
17608 -- AI-419: verify that the use of "limited" is consistent
17611 Orig_Decl : constant Node_Id := Original_Node (N);
17614 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
17615 and then not Limited_Present (Parent (Priv_T))
17616 and then not Synchronized_Present (Parent (Priv_T))
17617 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
17619 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
17620 and then Limited_Present (Type_Definition (Orig_Decl))
17623 ("full view of non-limited extension cannot be limited", N);
17627 -- Ada 2005 (AI-443): A synchronized private extension must be
17628 -- completed by a task or protected type.
17630 if Ada_Version >= Ada_2005
17631 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
17632 and then Synchronized_Present (Parent (Priv_T))
17633 and then not Is_Concurrent_Type (Full_T)
17635 Error_Msg_N ("full view of synchronized extension must " &
17636 "be synchronized type", N);
17639 -- Ada 2005 AI-363: if the full view has discriminants with
17640 -- defaults, it is illegal to declare constrained access subtypes
17641 -- whose designated type is the current type. This allows objects
17642 -- of the type that are declared in the heap to be unconstrained.
17644 if not Has_Unknown_Discriminants (Priv_T)
17645 and then not Has_Discriminants (Priv_T)
17646 and then Has_Discriminants (Full_T)
17648 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
17650 Set_Has_Constrained_Partial_View (Full_T);
17651 Set_Has_Constrained_Partial_View (Priv_T);
17654 -- Create a full declaration for all its subtypes recorded in
17655 -- Private_Dependents and swap them similarly to the base type. These
17656 -- are subtypes that have been define before the full declaration of
17657 -- the private type. We also swap the entry in Private_Dependents list
17658 -- so we can properly restore the private view on exit from the scope.
17661 Priv_Elmt : Elmt_Id;
17666 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
17667 while Present (Priv_Elmt) loop
17668 Priv := Node (Priv_Elmt);
17670 if Ekind_In (Priv, E_Private_Subtype,
17671 E_Limited_Private_Subtype,
17672 E_Record_Subtype_With_Private)
17674 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
17675 Set_Is_Itype (Full);
17676 Set_Parent (Full, Parent (Priv));
17677 Set_Associated_Node_For_Itype (Full, N);
17679 -- Now we need to complete the private subtype, but since the
17680 -- base type has already been swapped, we must also swap the
17681 -- subtypes (and thus, reverse the arguments in the call to
17682 -- Complete_Private_Subtype).
17684 Copy_And_Swap (Priv, Full);
17685 Complete_Private_Subtype (Full, Priv, Full_T, N);
17686 Replace_Elmt (Priv_Elmt, Full);
17689 Next_Elmt (Priv_Elmt);
17693 -- If the private view was tagged, copy the new primitive operations
17694 -- from the private view to the full view.
17696 if Is_Tagged_Type (Full_T) then
17698 Disp_Typ : Entity_Id;
17699 Full_List : Elist_Id;
17701 Prim_Elmt : Elmt_Id;
17702 Priv_List : Elist_Id;
17706 L : Elist_Id) return Boolean;
17707 -- Determine whether list L contains element E
17715 L : Elist_Id) return Boolean
17717 List_Elmt : Elmt_Id;
17720 List_Elmt := First_Elmt (L);
17721 while Present (List_Elmt) loop
17722 if Node (List_Elmt) = E then
17726 Next_Elmt (List_Elmt);
17732 -- Start of processing
17735 if Is_Tagged_Type (Priv_T) then
17736 Priv_List := Primitive_Operations (Priv_T);
17737 Prim_Elmt := First_Elmt (Priv_List);
17739 -- In the case of a concurrent type completing a private tagged
17740 -- type, primitives may have been declared in between the two
17741 -- views. These subprograms need to be wrapped the same way
17742 -- entries and protected procedures are handled because they
17743 -- cannot be directly shared by the two views.
17745 if Is_Concurrent_Type (Full_T) then
17747 Conc_Typ : constant Entity_Id :=
17748 Corresponding_Record_Type (Full_T);
17749 Curr_Nod : Node_Id := Parent (Conc_Typ);
17750 Wrap_Spec : Node_Id;
17753 while Present (Prim_Elmt) loop
17754 Prim := Node (Prim_Elmt);
17756 if Comes_From_Source (Prim)
17757 and then not Is_Abstract_Subprogram (Prim)
17760 Make_Subprogram_Declaration (Sloc (Prim),
17764 Obj_Typ => Conc_Typ,
17766 Parameter_Specifications (
17769 Insert_After (Curr_Nod, Wrap_Spec);
17770 Curr_Nod := Wrap_Spec;
17772 Analyze (Wrap_Spec);
17775 Next_Elmt (Prim_Elmt);
17781 -- For non-concurrent types, transfer explicit primitives, but
17782 -- omit those inherited from the parent of the private view
17783 -- since they will be re-inherited later on.
17786 Full_List := Primitive_Operations (Full_T);
17788 while Present (Prim_Elmt) loop
17789 Prim := Node (Prim_Elmt);
17791 if Comes_From_Source (Prim)
17792 and then not Contains (Prim, Full_List)
17794 Append_Elmt (Prim, Full_List);
17797 Next_Elmt (Prim_Elmt);
17801 -- Untagged private view
17804 Full_List := Primitive_Operations (Full_T);
17806 -- In this case the partial view is untagged, so here we locate
17807 -- all of the earlier primitives that need to be treated as
17808 -- dispatching (those that appear between the two views). Note
17809 -- that these additional operations must all be new operations
17810 -- (any earlier operations that override inherited operations
17811 -- of the full view will already have been inserted in the
17812 -- primitives list, marked by Check_Operation_From_Private_View
17813 -- as dispatching. Note that implicit "/=" operators are
17814 -- excluded from being added to the primitives list since they
17815 -- shouldn't be treated as dispatching (tagged "/=" is handled
17818 Prim := Next_Entity (Full_T);
17819 while Present (Prim) and then Prim /= Priv_T loop
17820 if Ekind_In (Prim, E_Procedure, E_Function) then
17821 Disp_Typ := Find_Dispatching_Type (Prim);
17823 if Disp_Typ = Full_T
17824 and then (Chars (Prim) /= Name_Op_Ne
17825 or else Comes_From_Source (Prim))
17827 Check_Controlling_Formals (Full_T, Prim);
17829 if not Is_Dispatching_Operation (Prim) then
17830 Append_Elmt (Prim, Full_List);
17831 Set_Is_Dispatching_Operation (Prim, True);
17832 Set_DT_Position (Prim, No_Uint);
17835 elsif Is_Dispatching_Operation (Prim)
17836 and then Disp_Typ /= Full_T
17839 -- Verify that it is not otherwise controlled by a
17840 -- formal or a return value of type T.
17842 Check_Controlling_Formals (Disp_Typ, Prim);
17846 Next_Entity (Prim);
17850 -- For the tagged case, the two views can share the same primitive
17851 -- operations list and the same class-wide type. Update attributes
17852 -- of the class-wide type which depend on the full declaration.
17854 if Is_Tagged_Type (Priv_T) then
17855 Set_Direct_Primitive_Operations (Priv_T, Full_List);
17856 Set_Class_Wide_Type
17857 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
17859 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
17864 -- Ada 2005 AI 161: Check preelaboratable initialization consistency
17866 if Known_To_Have_Preelab_Init (Priv_T) then
17868 -- Case where there is a pragma Preelaborable_Initialization. We
17869 -- always allow this in predefined units, which is a bit of a kludge,
17870 -- but it means we don't have to struggle to meet the requirements in
17871 -- the RM for having Preelaborable Initialization. Otherwise we
17872 -- require that the type meets the RM rules. But we can't check that
17873 -- yet, because of the rule about overriding Initialize, so we simply
17874 -- set a flag that will be checked at freeze time.
17876 if not In_Predefined_Unit (Full_T) then
17877 Set_Must_Have_Preelab_Init (Full_T);
17881 -- If pragma CPP_Class was applied to the private type declaration,
17882 -- propagate it now to the full type declaration.
17884 if Is_CPP_Class (Priv_T) then
17885 Set_Is_CPP_Class (Full_T);
17886 Set_Convention (Full_T, Convention_CPP);
17889 -- If the private view has user specified stream attributes, then so has
17892 -- Why the test, how could these flags be already set in Full_T ???
17894 if Has_Specified_Stream_Read (Priv_T) then
17895 Set_Has_Specified_Stream_Read (Full_T);
17898 if Has_Specified_Stream_Write (Priv_T) then
17899 Set_Has_Specified_Stream_Write (Full_T);
17902 if Has_Specified_Stream_Input (Priv_T) then
17903 Set_Has_Specified_Stream_Input (Full_T);
17906 if Has_Specified_Stream_Output (Priv_T) then
17907 Set_Has_Specified_Stream_Output (Full_T);
17910 -- Propagate invariants to full type
17912 if Has_Invariants (Priv_T) then
17913 Set_Has_Invariants (Full_T);
17914 Set_Invariant_Procedure (Full_T, Invariant_Procedure (Priv_T));
17917 if Has_Inheritable_Invariants (Priv_T) then
17918 Set_Has_Inheritable_Invariants (Full_T);
17921 -- Propagate predicates to full type
17923 if Has_Predicates (Priv_T) then
17924 Set_Predicate_Function (Priv_T, Predicate_Function (Full_T));
17925 Set_Has_Predicates (Priv_T);
17927 end Process_Full_View;
17929 -----------------------------------
17930 -- Process_Incomplete_Dependents --
17931 -----------------------------------
17933 procedure Process_Incomplete_Dependents
17935 Full_T : Entity_Id;
17938 Inc_Elmt : Elmt_Id;
17939 Priv_Dep : Entity_Id;
17940 New_Subt : Entity_Id;
17942 Disc_Constraint : Elist_Id;
17945 if No (Private_Dependents (Inc_T)) then
17949 -- Itypes that may be generated by the completion of an incomplete
17950 -- subtype are not used by the back-end and not attached to the tree.
17951 -- They are created only for constraint-checking purposes.
17953 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
17954 while Present (Inc_Elmt) loop
17955 Priv_Dep := Node (Inc_Elmt);
17957 if Ekind (Priv_Dep) = E_Subprogram_Type then
17959 -- An Access_To_Subprogram type may have a return type or a
17960 -- parameter type that is incomplete. Replace with the full view.
17962 if Etype (Priv_Dep) = Inc_T then
17963 Set_Etype (Priv_Dep, Full_T);
17967 Formal : Entity_Id;
17970 Formal := First_Formal (Priv_Dep);
17971 while Present (Formal) loop
17972 if Etype (Formal) = Inc_T then
17973 Set_Etype (Formal, Full_T);
17976 Next_Formal (Formal);
17980 elsif Is_Overloadable (Priv_Dep) then
17982 -- If a subprogram in the incomplete dependents list is primitive
17983 -- for a tagged full type then mark it as a dispatching operation,
17984 -- check whether it overrides an inherited subprogram, and check
17985 -- restrictions on its controlling formals. Note that a protected
17986 -- operation is never dispatching: only its wrapper operation
17987 -- (which has convention Ada) is.
17989 if Is_Tagged_Type (Full_T)
17990 and then Is_Primitive (Priv_Dep)
17991 and then Convention (Priv_Dep) /= Convention_Protected
17993 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
17994 Set_Is_Dispatching_Operation (Priv_Dep);
17995 Check_Controlling_Formals (Full_T, Priv_Dep);
17998 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
18000 -- Can happen during processing of a body before the completion
18001 -- of a TA type. Ignore, because spec is also on dependent list.
18005 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
18006 -- corresponding subtype of the full view.
18008 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
18009 Set_Subtype_Indication
18010 (Parent (Priv_Dep), New_Reference_To (Full_T, Sloc (Priv_Dep)));
18011 Set_Etype (Priv_Dep, Full_T);
18012 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
18013 Set_Analyzed (Parent (Priv_Dep), False);
18015 -- Reanalyze the declaration, suppressing the call to
18016 -- Enter_Name to avoid duplicate names.
18018 Analyze_Subtype_Declaration
18019 (N => Parent (Priv_Dep),
18022 -- Dependent is a subtype
18025 -- We build a new subtype indication using the full view of the
18026 -- incomplete parent. The discriminant constraints have been
18027 -- elaborated already at the point of the subtype declaration.
18029 New_Subt := Create_Itype (E_Void, N);
18031 if Has_Discriminants (Full_T) then
18032 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
18034 Disc_Constraint := No_Elist;
18037 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
18038 Set_Full_View (Priv_Dep, New_Subt);
18041 Next_Elmt (Inc_Elmt);
18043 end Process_Incomplete_Dependents;
18045 --------------------------------
18046 -- Process_Range_Expr_In_Decl --
18047 --------------------------------
18049 procedure Process_Range_Expr_In_Decl
18052 Check_List : List_Id := Empty_List;
18053 R_Check_Off : Boolean := False;
18054 In_Iter_Schm : Boolean := False)
18057 R_Checks : Check_Result;
18058 Insert_Node : Node_Id;
18059 Def_Id : Entity_Id;
18062 Analyze_And_Resolve (R, Base_Type (T));
18064 if Nkind (R) = N_Range then
18066 -- In SPARK, all ranges should be static, with the exception of the
18067 -- discrete type definition of a loop parameter specification.
18069 if not In_Iter_Schm
18070 and then not Is_Static_Range (R)
18072 Check_SPARK_Restriction ("range should be static", R);
18075 Lo := Low_Bound (R);
18076 Hi := High_Bound (R);
18078 -- We need to ensure validity of the bounds here, because if we
18079 -- go ahead and do the expansion, then the expanded code will get
18080 -- analyzed with range checks suppressed and we miss the check.
18082 Validity_Check_Range (R);
18084 -- If there were errors in the declaration, try and patch up some
18085 -- common mistakes in the bounds. The cases handled are literals
18086 -- which are Integer where the expected type is Real and vice versa.
18087 -- These corrections allow the compilation process to proceed further
18088 -- along since some basic assumptions of the format of the bounds
18091 if Etype (R) = Any_Type then
18093 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
18095 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
18097 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
18099 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
18101 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
18103 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
18105 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
18107 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
18114 -- If the bounds of the range have been mistakenly given as string
18115 -- literals (perhaps in place of character literals), then an error
18116 -- has already been reported, but we rewrite the string literal as a
18117 -- bound of the range's type to avoid blowups in later processing
18118 -- that looks at static values.
18120 if Nkind (Lo) = N_String_Literal then
18122 Make_Attribute_Reference (Sloc (Lo),
18123 Attribute_Name => Name_First,
18124 Prefix => New_Reference_To (T, Sloc (Lo))));
18125 Analyze_And_Resolve (Lo);
18128 if Nkind (Hi) = N_String_Literal then
18130 Make_Attribute_Reference (Sloc (Hi),
18131 Attribute_Name => Name_First,
18132 Prefix => New_Reference_To (T, Sloc (Hi))));
18133 Analyze_And_Resolve (Hi);
18136 -- If bounds aren't scalar at this point then exit, avoiding
18137 -- problems with further processing of the range in this procedure.
18139 if not Is_Scalar_Type (Etype (Lo)) then
18143 -- Resolve (actually Sem_Eval) has checked that the bounds are in
18144 -- then range of the base type. Here we check whether the bounds
18145 -- are in the range of the subtype itself. Note that if the bounds
18146 -- represent the null range the Constraint_Error exception should
18149 -- ??? The following code should be cleaned up as follows
18151 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
18152 -- is done in the call to Range_Check (R, T); below
18154 -- 2. The use of R_Check_Off should be investigated and possibly
18155 -- removed, this would clean up things a bit.
18157 if Is_Null_Range (Lo, Hi) then
18161 -- Capture values of bounds and generate temporaries for them
18162 -- if needed, before applying checks, since checks may cause
18163 -- duplication of the expression without forcing evaluation.
18165 if Expander_Active then
18166 Force_Evaluation (Lo);
18167 Force_Evaluation (Hi);
18170 -- We use a flag here instead of suppressing checks on the
18171 -- type because the type we check against isn't necessarily
18172 -- the place where we put the check.
18174 if not R_Check_Off then
18175 R_Checks := Get_Range_Checks (R, T);
18177 -- Look up tree to find an appropriate insertion point. We
18178 -- can't just use insert_actions because later processing
18179 -- depends on the insertion node. Prior to Ada2012 the
18180 -- insertion point could only be a declaration or a loop, but
18181 -- quantified expressions can appear within any context in an
18182 -- expression, and the insertion point can be any statement,
18183 -- pragma, or declaration.
18185 Insert_Node := Parent (R);
18186 while Present (Insert_Node) loop
18188 Nkind (Insert_Node) in N_Declaration
18191 (Insert_Node, N_Component_Declaration,
18192 N_Loop_Parameter_Specification,
18193 N_Function_Specification,
18194 N_Procedure_Specification);
18196 exit when Nkind (Insert_Node) in N_Later_Decl_Item
18197 or else Nkind (Insert_Node) in
18198 N_Statement_Other_Than_Procedure_Call
18199 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
18202 Insert_Node := Parent (Insert_Node);
18205 -- Why would Type_Decl not be present??? Without this test,
18206 -- short regression tests fail.
18208 if Present (Insert_Node) then
18210 -- Case of loop statement. Verify that the range is part
18211 -- of the subtype indication of the iteration scheme.
18213 if Nkind (Insert_Node) = N_Loop_Statement then
18218 Indic := Parent (R);
18219 while Present (Indic)
18220 and then Nkind (Indic) /= N_Subtype_Indication
18222 Indic := Parent (Indic);
18225 if Present (Indic) then
18226 Def_Id := Etype (Subtype_Mark (Indic));
18228 Insert_Range_Checks
18232 Sloc (Insert_Node),
18234 Do_Before => True);
18238 -- Insertion before a declaration. If the declaration
18239 -- includes discriminants, the list of applicable checks
18240 -- is given by the caller.
18242 elsif Nkind (Insert_Node) in N_Declaration then
18243 Def_Id := Defining_Identifier (Insert_Node);
18245 if (Ekind (Def_Id) = E_Record_Type
18246 and then Depends_On_Discriminant (R))
18248 (Ekind (Def_Id) = E_Protected_Type
18249 and then Has_Discriminants (Def_Id))
18251 Append_Range_Checks
18253 Check_List, Def_Id, Sloc (Insert_Node), R);
18256 Insert_Range_Checks
18258 Insert_Node, Def_Id, Sloc (Insert_Node), R);
18262 -- Insertion before a statement. Range appears in the
18263 -- context of a quantified expression. Insertion will
18264 -- take place when expression is expanded.
18273 -- Case of other than an explicit N_Range node
18275 elsif Expander_Active then
18276 Get_Index_Bounds (R, Lo, Hi);
18277 Force_Evaluation (Lo);
18278 Force_Evaluation (Hi);
18280 end Process_Range_Expr_In_Decl;
18282 --------------------------------------
18283 -- Process_Real_Range_Specification --
18284 --------------------------------------
18286 procedure Process_Real_Range_Specification (Def : Node_Id) is
18287 Spec : constant Node_Id := Real_Range_Specification (Def);
18290 Err : Boolean := False;
18292 procedure Analyze_Bound (N : Node_Id);
18293 -- Analyze and check one bound
18295 -------------------
18296 -- Analyze_Bound --
18297 -------------------
18299 procedure Analyze_Bound (N : Node_Id) is
18301 Analyze_And_Resolve (N, Any_Real);
18303 if not Is_OK_Static_Expression (N) then
18304 Flag_Non_Static_Expr
18305 ("bound in real type definition is not static!", N);
18310 -- Start of processing for Process_Real_Range_Specification
18313 if Present (Spec) then
18314 Lo := Low_Bound (Spec);
18315 Hi := High_Bound (Spec);
18316 Analyze_Bound (Lo);
18317 Analyze_Bound (Hi);
18319 -- If error, clear away junk range specification
18322 Set_Real_Range_Specification (Def, Empty);
18325 end Process_Real_Range_Specification;
18327 ---------------------
18328 -- Process_Subtype --
18329 ---------------------
18331 function Process_Subtype
18333 Related_Nod : Node_Id;
18334 Related_Id : Entity_Id := Empty;
18335 Suffix : Character := ' ') return Entity_Id
18338 Def_Id : Entity_Id;
18339 Error_Node : Node_Id;
18340 Full_View_Id : Entity_Id;
18341 Subtype_Mark_Id : Entity_Id;
18343 May_Have_Null_Exclusion : Boolean;
18345 procedure Check_Incomplete (T : Entity_Id);
18346 -- Called to verify that an incomplete type is not used prematurely
18348 ----------------------
18349 -- Check_Incomplete --
18350 ----------------------
18352 procedure Check_Incomplete (T : Entity_Id) is
18354 -- Ada 2005 (AI-412): Incomplete subtypes are legal
18356 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
18358 not (Ada_Version >= Ada_2005
18360 (Nkind (Parent (T)) = N_Subtype_Declaration
18362 (Nkind (Parent (T)) = N_Subtype_Indication
18363 and then Nkind (Parent (Parent (T))) =
18364 N_Subtype_Declaration)))
18366 Error_Msg_N ("invalid use of type before its full declaration", T);
18368 end Check_Incomplete;
18370 -- Start of processing for Process_Subtype
18373 -- Case of no constraints present
18375 if Nkind (S) /= N_Subtype_Indication then
18377 Check_Incomplete (S);
18380 -- Ada 2005 (AI-231): Static check
18382 if Ada_Version >= Ada_2005
18383 and then Present (P)
18384 and then Null_Exclusion_Present (P)
18385 and then Nkind (P) /= N_Access_To_Object_Definition
18386 and then not Is_Access_Type (Entity (S))
18388 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
18391 -- The following is ugly, can't we have a range or even a flag???
18393 May_Have_Null_Exclusion :=
18394 Nkind_In (P, N_Access_Definition,
18395 N_Access_Function_Definition,
18396 N_Access_Procedure_Definition,
18397 N_Access_To_Object_Definition,
18399 N_Component_Definition)
18401 Nkind_In (P, N_Derived_Type_Definition,
18402 N_Discriminant_Specification,
18403 N_Formal_Object_Declaration,
18404 N_Object_Declaration,
18405 N_Object_Renaming_Declaration,
18406 N_Parameter_Specification,
18407 N_Subtype_Declaration);
18409 -- Create an Itype that is a duplicate of Entity (S) but with the
18410 -- null-exclusion attribute.
18412 if May_Have_Null_Exclusion
18413 and then Is_Access_Type (Entity (S))
18414 and then Null_Exclusion_Present (P)
18416 -- No need to check the case of an access to object definition.
18417 -- It is correct to define double not-null pointers.
18420 -- type Not_Null_Int_Ptr is not null access Integer;
18421 -- type Acc is not null access Not_Null_Int_Ptr;
18423 and then Nkind (P) /= N_Access_To_Object_Definition
18425 if Can_Never_Be_Null (Entity (S)) then
18426 case Nkind (Related_Nod) is
18427 when N_Full_Type_Declaration =>
18428 if Nkind (Type_Definition (Related_Nod))
18429 in N_Array_Type_Definition
18433 (Component_Definition
18434 (Type_Definition (Related_Nod)));
18437 Subtype_Indication (Type_Definition (Related_Nod));
18440 when N_Subtype_Declaration =>
18441 Error_Node := Subtype_Indication (Related_Nod);
18443 when N_Object_Declaration =>
18444 Error_Node := Object_Definition (Related_Nod);
18446 when N_Component_Declaration =>
18448 Subtype_Indication (Component_Definition (Related_Nod));
18450 when N_Allocator =>
18451 Error_Node := Expression (Related_Nod);
18454 pragma Assert (False);
18455 Error_Node := Related_Nod;
18459 ("`NOT NULL` not allowed (& already excludes null)",
18465 Create_Null_Excluding_Itype
18467 Related_Nod => P));
18468 Set_Entity (S, Etype (S));
18473 -- Case of constraint present, so that we have an N_Subtype_Indication
18474 -- node (this node is created only if constraints are present).
18477 Find_Type (Subtype_Mark (S));
18479 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
18481 (Nkind (Parent (S)) = N_Subtype_Declaration
18482 and then Is_Itype (Defining_Identifier (Parent (S))))
18484 Check_Incomplete (Subtype_Mark (S));
18488 Subtype_Mark_Id := Entity (Subtype_Mark (S));
18490 -- Explicit subtype declaration case
18492 if Nkind (P) = N_Subtype_Declaration then
18493 Def_Id := Defining_Identifier (P);
18495 -- Explicit derived type definition case
18497 elsif Nkind (P) = N_Derived_Type_Definition then
18498 Def_Id := Defining_Identifier (Parent (P));
18500 -- Implicit case, the Def_Id must be created as an implicit type.
18501 -- The one exception arises in the case of concurrent types, array
18502 -- and access types, where other subsidiary implicit types may be
18503 -- created and must appear before the main implicit type. In these
18504 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
18505 -- has not yet been called to create Def_Id.
18508 if Is_Array_Type (Subtype_Mark_Id)
18509 or else Is_Concurrent_Type (Subtype_Mark_Id)
18510 or else Is_Access_Type (Subtype_Mark_Id)
18514 -- For the other cases, we create a new unattached Itype,
18515 -- and set the indication to ensure it gets attached later.
18519 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
18523 -- If the kind of constraint is invalid for this kind of type,
18524 -- then give an error, and then pretend no constraint was given.
18526 if not Is_Valid_Constraint_Kind
18527 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
18530 ("incorrect constraint for this kind of type", Constraint (S));
18532 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
18534 -- Set Ekind of orphan itype, to prevent cascaded errors
18536 if Present (Def_Id) then
18537 Set_Ekind (Def_Id, Ekind (Any_Type));
18540 -- Make recursive call, having got rid of the bogus constraint
18542 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
18545 -- Remaining processing depends on type
18547 case Ekind (Subtype_Mark_Id) is
18548 when Access_Kind =>
18549 Constrain_Access (Def_Id, S, Related_Nod);
18552 and then Is_Itype (Designated_Type (Def_Id))
18553 and then Nkind (Related_Nod) = N_Subtype_Declaration
18554 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
18556 Build_Itype_Reference
18557 (Designated_Type (Def_Id), Related_Nod);
18561 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
18563 when Decimal_Fixed_Point_Kind =>
18564 Constrain_Decimal (Def_Id, S);
18566 when Enumeration_Kind =>
18567 Constrain_Enumeration (Def_Id, S);
18569 when Ordinary_Fixed_Point_Kind =>
18570 Constrain_Ordinary_Fixed (Def_Id, S);
18573 Constrain_Float (Def_Id, S);
18575 when Integer_Kind =>
18576 Constrain_Integer (Def_Id, S);
18578 when E_Record_Type |
18581 E_Incomplete_Type =>
18582 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
18584 if Ekind (Def_Id) = E_Incomplete_Type then
18585 Set_Private_Dependents (Def_Id, New_Elmt_List);
18588 when Private_Kind =>
18589 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
18590 Set_Private_Dependents (Def_Id, New_Elmt_List);
18592 -- In case of an invalid constraint prevent further processing
18593 -- since the type constructed is missing expected fields.
18595 if Etype (Def_Id) = Any_Type then
18599 -- If the full view is that of a task with discriminants,
18600 -- we must constrain both the concurrent type and its
18601 -- corresponding record type. Otherwise we will just propagate
18602 -- the constraint to the full view, if available.
18604 if Present (Full_View (Subtype_Mark_Id))
18605 and then Has_Discriminants (Subtype_Mark_Id)
18606 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
18609 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
18611 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
18612 Constrain_Concurrent (Full_View_Id, S,
18613 Related_Nod, Related_Id, Suffix);
18614 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
18615 Set_Full_View (Def_Id, Full_View_Id);
18617 -- Introduce an explicit reference to the private subtype,
18618 -- to prevent scope anomalies in gigi if first use appears
18619 -- in a nested context, e.g. a later function body.
18620 -- Should this be generated in other contexts than a full
18621 -- type declaration?
18623 if Is_Itype (Def_Id)
18625 Nkind (Parent (P)) = N_Full_Type_Declaration
18627 Build_Itype_Reference (Def_Id, Parent (P));
18631 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
18634 when Concurrent_Kind =>
18635 Constrain_Concurrent (Def_Id, S,
18636 Related_Nod, Related_Id, Suffix);
18639 Error_Msg_N ("invalid subtype mark in subtype indication", S);
18642 -- Size and Convention are always inherited from the base type
18644 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
18645 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
18649 end Process_Subtype;
18651 ---------------------------------------
18652 -- Check_Anonymous_Access_Components --
18653 ---------------------------------------
18655 procedure Check_Anonymous_Access_Components
18656 (Typ_Decl : Node_Id;
18659 Comp_List : Node_Id)
18661 Loc : constant Source_Ptr := Sloc (Typ_Decl);
18662 Anon_Access : Entity_Id;
18665 Comp_Def : Node_Id;
18667 Type_Def : Node_Id;
18669 procedure Build_Incomplete_Type_Declaration;
18670 -- If the record type contains components that include an access to the
18671 -- current record, then create an incomplete type declaration for the
18672 -- record, to be used as the designated type of the anonymous access.
18673 -- This is done only once, and only if there is no previous partial
18674 -- view of the type.
18676 function Designates_T (Subt : Node_Id) return Boolean;
18677 -- Check whether a node designates the enclosing record type, or 'Class
18680 function Mentions_T (Acc_Def : Node_Id) return Boolean;
18681 -- Check whether an access definition includes a reference to
18682 -- the enclosing record type. The reference can be a subtype mark
18683 -- in the access definition itself, a 'Class attribute reference, or
18684 -- recursively a reference appearing in a parameter specification
18685 -- or result definition of an access_to_subprogram definition.
18687 --------------------------------------
18688 -- Build_Incomplete_Type_Declaration --
18689 --------------------------------------
18691 procedure Build_Incomplete_Type_Declaration is
18696 -- Is_Tagged indicates whether the type is tagged. It is tagged if
18697 -- it's "is new ... with record" or else "is tagged record ...".
18699 Is_Tagged : constant Boolean :=
18700 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
18703 (Record_Extension_Part (Type_Definition (Typ_Decl))))
18705 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
18706 and then Tagged_Present (Type_Definition (Typ_Decl)));
18709 -- If there is a previous partial view, no need to create a new one
18710 -- If the partial view, given by Prev, is incomplete, If Prev is
18711 -- a private declaration, full declaration is flagged accordingly.
18713 if Prev /= Typ then
18715 Make_Class_Wide_Type (Prev);
18716 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
18717 Set_Etype (Class_Wide_Type (Typ), Typ);
18722 elsif Has_Private_Declaration (Typ) then
18724 -- If we refer to T'Class inside T, and T is the completion of a
18725 -- private type, then we need to make sure the class-wide type
18729 Make_Class_Wide_Type (Typ);
18734 -- If there was a previous anonymous access type, the incomplete
18735 -- type declaration will have been created already.
18737 elsif Present (Current_Entity (Typ))
18738 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
18739 and then Full_View (Current_Entity (Typ)) = Typ
18742 and then Comes_From_Source (Current_Entity (Typ))
18743 and then not Is_Tagged_Type (Current_Entity (Typ))
18745 Make_Class_Wide_Type (Typ);
18747 ("incomplete view of tagged type should be declared tagged?",
18748 Parent (Current_Entity (Typ)));
18753 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
18754 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
18756 -- Type has already been inserted into the current scope. Remove
18757 -- it, and add incomplete declaration for type, so that subsequent
18758 -- anonymous access types can use it. The entity is unchained from
18759 -- the homonym list and from immediate visibility. After analysis,
18760 -- the entity in the incomplete declaration becomes immediately
18761 -- visible in the record declaration that follows.
18763 H := Current_Entity (Typ);
18766 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
18769 and then Homonym (H) /= Typ
18771 H := Homonym (Typ);
18774 Set_Homonym (H, Homonym (Typ));
18777 Insert_Before (Typ_Decl, Decl);
18779 Set_Full_View (Inc_T, Typ);
18783 -- Create a common class-wide type for both views, and set the
18784 -- Etype of the class-wide type to the full view.
18786 Make_Class_Wide_Type (Inc_T);
18787 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
18788 Set_Etype (Class_Wide_Type (Typ), Typ);
18791 end Build_Incomplete_Type_Declaration;
18797 function Designates_T (Subt : Node_Id) return Boolean is
18798 Type_Id : constant Name_Id := Chars (Typ);
18800 function Names_T (Nam : Node_Id) return Boolean;
18801 -- The record type has not been introduced in the current scope
18802 -- yet, so we must examine the name of the type itself, either
18803 -- an identifier T, or an expanded name of the form P.T, where
18804 -- P denotes the current scope.
18810 function Names_T (Nam : Node_Id) return Boolean is
18812 if Nkind (Nam) = N_Identifier then
18813 return Chars (Nam) = Type_Id;
18815 elsif Nkind (Nam) = N_Selected_Component then
18816 if Chars (Selector_Name (Nam)) = Type_Id then
18817 if Nkind (Prefix (Nam)) = N_Identifier then
18818 return Chars (Prefix (Nam)) = Chars (Current_Scope);
18820 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
18821 return Chars (Selector_Name (Prefix (Nam))) =
18822 Chars (Current_Scope);
18836 -- Start of processing for Designates_T
18839 if Nkind (Subt) = N_Identifier then
18840 return Chars (Subt) = Type_Id;
18842 -- Reference can be through an expanded name which has not been
18843 -- analyzed yet, and which designates enclosing scopes.
18845 elsif Nkind (Subt) = N_Selected_Component then
18846 if Names_T (Subt) then
18849 -- Otherwise it must denote an entity that is already visible.
18850 -- The access definition may name a subtype of the enclosing
18851 -- type, if there is a previous incomplete declaration for it.
18854 Find_Selected_Component (Subt);
18856 Is_Entity_Name (Subt)
18857 and then Scope (Entity (Subt)) = Current_Scope
18859 (Chars (Base_Type (Entity (Subt))) = Type_Id
18861 (Is_Class_Wide_Type (Entity (Subt))
18863 Chars (Etype (Base_Type (Entity (Subt)))) =
18867 -- A reference to the current type may appear as the prefix of
18868 -- a 'Class attribute.
18870 elsif Nkind (Subt) = N_Attribute_Reference
18871 and then Attribute_Name (Subt) = Name_Class
18873 return Names_T (Prefix (Subt));
18884 function Mentions_T (Acc_Def : Node_Id) return Boolean is
18885 Param_Spec : Node_Id;
18887 Acc_Subprg : constant Node_Id :=
18888 Access_To_Subprogram_Definition (Acc_Def);
18891 if No (Acc_Subprg) then
18892 return Designates_T (Subtype_Mark (Acc_Def));
18895 -- Component is an access_to_subprogram: examine its formals,
18896 -- and result definition in the case of an access_to_function.
18898 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
18899 while Present (Param_Spec) loop
18900 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
18901 and then Mentions_T (Parameter_Type (Param_Spec))
18905 elsif Designates_T (Parameter_Type (Param_Spec)) then
18912 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
18913 if Nkind (Result_Definition (Acc_Subprg)) =
18914 N_Access_Definition
18916 return Mentions_T (Result_Definition (Acc_Subprg));
18918 return Designates_T (Result_Definition (Acc_Subprg));
18925 -- Start of processing for Check_Anonymous_Access_Components
18928 if No (Comp_List) then
18932 Comp := First (Component_Items (Comp_List));
18933 while Present (Comp) loop
18934 if Nkind (Comp) = N_Component_Declaration
18936 (Access_Definition (Component_Definition (Comp)))
18938 Mentions_T (Access_Definition (Component_Definition (Comp)))
18940 Comp_Def := Component_Definition (Comp);
18942 Access_To_Subprogram_Definition
18943 (Access_Definition (Comp_Def));
18945 Build_Incomplete_Type_Declaration;
18946 Anon_Access := Make_Temporary (Loc, 'S');
18948 -- Create a declaration for the anonymous access type: either
18949 -- an access_to_object or an access_to_subprogram.
18951 if Present (Acc_Def) then
18952 if Nkind (Acc_Def) = N_Access_Function_Definition then
18954 Make_Access_Function_Definition (Loc,
18955 Parameter_Specifications =>
18956 Parameter_Specifications (Acc_Def),
18957 Result_Definition => Result_Definition (Acc_Def));
18960 Make_Access_Procedure_Definition (Loc,
18961 Parameter_Specifications =>
18962 Parameter_Specifications (Acc_Def));
18967 Make_Access_To_Object_Definition (Loc,
18968 Subtype_Indication =>
18971 (Access_Definition (Comp_Def))));
18973 Set_Constant_Present
18974 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
18976 (Type_Def, All_Present (Access_Definition (Comp_Def)));
18979 Set_Null_Exclusion_Present
18981 Null_Exclusion_Present (Access_Definition (Comp_Def)));
18984 Make_Full_Type_Declaration (Loc,
18985 Defining_Identifier => Anon_Access,
18986 Type_Definition => Type_Def);
18988 Insert_Before (Typ_Decl, Decl);
18991 -- If an access to subprogram, create the extra formals
18993 if Present (Acc_Def) then
18994 Create_Extra_Formals (Designated_Type (Anon_Access));
18996 -- If an access to object, preserve entity of designated type,
18997 -- for ASIS use, before rewriting the component definition.
19004 Desig := Entity (Subtype_Indication (Type_Def));
19006 -- If the access definition is to the current record,
19007 -- the visible entity at this point is an incomplete
19008 -- type. Retrieve the full view to simplify ASIS queries
19010 if Ekind (Desig) = E_Incomplete_Type then
19011 Desig := Full_View (Desig);
19015 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
19020 Make_Component_Definition (Loc,
19021 Subtype_Indication =>
19022 New_Occurrence_Of (Anon_Access, Loc)));
19024 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
19025 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
19027 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
19030 Set_Is_Local_Anonymous_Access (Anon_Access);
19036 if Present (Variant_Part (Comp_List)) then
19040 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
19041 while Present (V) loop
19042 Check_Anonymous_Access_Components
19043 (Typ_Decl, Typ, Prev, Component_List (V));
19044 Next_Non_Pragma (V);
19048 end Check_Anonymous_Access_Components;
19050 --------------------------------
19051 -- Preanalyze_Spec_Expression --
19052 --------------------------------
19054 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
19055 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
19057 In_Spec_Expression := True;
19058 Preanalyze_And_Resolve (N, T);
19059 In_Spec_Expression := Save_In_Spec_Expression;
19060 end Preanalyze_Spec_Expression;
19062 -----------------------------
19063 -- Record_Type_Declaration --
19064 -----------------------------
19066 procedure Record_Type_Declaration
19071 Def : constant Node_Id := Type_Definition (N);
19072 Is_Tagged : Boolean;
19073 Tag_Comp : Entity_Id;
19076 -- These flags must be initialized before calling Process_Discriminants
19077 -- because this routine makes use of them.
19079 Set_Ekind (T, E_Record_Type);
19081 Init_Size_Align (T);
19082 Set_Interfaces (T, No_Elist);
19083 Set_Stored_Constraint (T, No_Elist);
19087 if Ada_Version < Ada_2005
19088 or else not Interface_Present (Def)
19090 if Limited_Present (Def) then
19091 Check_SPARK_Restriction ("limited is not allowed", N);
19094 if Abstract_Present (Def) then
19095 Check_SPARK_Restriction ("abstract is not allowed", N);
19098 -- The flag Is_Tagged_Type might have already been set by
19099 -- Find_Type_Name if it detected an error for declaration T. This
19100 -- arises in the case of private tagged types where the full view
19101 -- omits the word tagged.
19104 Tagged_Present (Def)
19105 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
19107 Set_Is_Tagged_Type (T, Is_Tagged);
19108 Set_Is_Limited_Record (T, Limited_Present (Def));
19110 -- Type is abstract if full declaration carries keyword, or if
19111 -- previous partial view did.
19113 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
19114 or else Abstract_Present (Def));
19117 Check_SPARK_Restriction ("interface is not allowed", N);
19120 Analyze_Interface_Declaration (T, Def);
19122 if Present (Discriminant_Specifications (N)) then
19124 ("interface types cannot have discriminants",
19125 Defining_Identifier
19126 (First (Discriminant_Specifications (N))));
19130 -- First pass: if there are self-referential access components,
19131 -- create the required anonymous access type declarations, and if
19132 -- need be an incomplete type declaration for T itself.
19134 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
19136 if Ada_Version >= Ada_2005
19137 and then Present (Interface_List (Def))
19139 Check_Interfaces (N, Def);
19142 Ifaces_List : Elist_Id;
19145 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
19146 -- already in the parents.
19150 Ifaces_List => Ifaces_List,
19151 Exclude_Parents => True);
19153 Set_Interfaces (T, Ifaces_List);
19157 -- Records constitute a scope for the component declarations within.
19158 -- The scope is created prior to the processing of these declarations.
19159 -- Discriminants are processed first, so that they are visible when
19160 -- processing the other components. The Ekind of the record type itself
19161 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
19163 -- Enter record scope
19167 -- If an incomplete or private type declaration was already given for
19168 -- the type, then this scope already exists, and the discriminants have
19169 -- been declared within. We must verify that the full declaration
19170 -- matches the incomplete one.
19172 Check_Or_Process_Discriminants (N, T, Prev);
19174 Set_Is_Constrained (T, not Has_Discriminants (T));
19175 Set_Has_Delayed_Freeze (T, True);
19177 -- For tagged types add a manually analyzed component corresponding
19178 -- to the component _tag, the corresponding piece of tree will be
19179 -- expanded as part of the freezing actions if it is not a CPP_Class.
19183 -- Do not add the tag unless we are in expansion mode
19185 if Expander_Active then
19186 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
19187 Enter_Name (Tag_Comp);
19189 Set_Ekind (Tag_Comp, E_Component);
19190 Set_Is_Tag (Tag_Comp);
19191 Set_Is_Aliased (Tag_Comp);
19192 Set_Etype (Tag_Comp, RTE (RE_Tag));
19193 Set_DT_Entry_Count (Tag_Comp, No_Uint);
19194 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
19195 Init_Component_Location (Tag_Comp);
19197 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
19198 -- implemented interfaces.
19200 if Has_Interfaces (T) then
19201 Add_Interface_Tag_Components (N, T);
19205 Make_Class_Wide_Type (T);
19206 Set_Direct_Primitive_Operations (T, New_Elmt_List);
19209 -- We must suppress range checks when processing record components in
19210 -- the presence of discriminants, since we don't want spurious checks to
19211 -- be generated during their analysis, but Suppress_Range_Checks flags
19212 -- must be reset the after processing the record definition.
19214 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
19215 -- couldn't we just use the normal range check suppression method here.
19216 -- That would seem cleaner ???
19218 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
19219 Set_Kill_Range_Checks (T, True);
19220 Record_Type_Definition (Def, Prev);
19221 Set_Kill_Range_Checks (T, False);
19223 Record_Type_Definition (Def, Prev);
19226 -- Exit from record scope
19230 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
19231 -- the implemented interfaces and associate them an aliased entity.
19234 and then not Is_Empty_List (Interface_List (Def))
19236 Derive_Progenitor_Subprograms (T, T);
19238 end Record_Type_Declaration;
19240 ----------------------------
19241 -- Record_Type_Definition --
19242 ----------------------------
19244 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
19245 Component : Entity_Id;
19246 Ctrl_Components : Boolean := False;
19247 Final_Storage_Only : Boolean;
19251 if Ekind (Prev_T) = E_Incomplete_Type then
19252 T := Full_View (Prev_T);
19257 -- In SPARK, tagged types and type extensions may only be declared in
19258 -- the specification of library unit packages.
19260 if Present (Def) and then Is_Tagged_Type (T) then
19266 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
19267 Typ := Parent (Def);
19270 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
19271 Typ := Parent (Parent (Def));
19274 Ctxt := Parent (Typ);
19276 if Nkind (Ctxt) = N_Package_Body
19277 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
19279 Check_SPARK_Restriction
19280 ("type should be defined in package specification", Typ);
19282 elsif Nkind (Ctxt) /= N_Package_Specification
19283 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
19285 Check_SPARK_Restriction
19286 ("type should be defined in library unit package", Typ);
19291 Final_Storage_Only := not Is_Controlled (T);
19293 -- Ada 2005: check whether an explicit Limited is present in a derived
19294 -- type declaration.
19296 if Nkind (Parent (Def)) = N_Derived_Type_Definition
19297 and then Limited_Present (Parent (Def))
19299 Set_Is_Limited_Record (T);
19302 -- If the component list of a record type is defined by the reserved
19303 -- word null and there is no discriminant part, then the record type has
19304 -- no components and all records of the type are null records (RM 3.7)
19305 -- This procedure is also called to process the extension part of a
19306 -- record extension, in which case the current scope may have inherited
19310 or else No (Component_List (Def))
19311 or else Null_Present (Component_List (Def))
19313 if not Is_Tagged_Type (T) then
19314 Check_SPARK_Restriction ("non-tagged record cannot be null", Def);
19318 Analyze_Declarations (Component_Items (Component_List (Def)));
19320 if Present (Variant_Part (Component_List (Def))) then
19321 Check_SPARK_Restriction ("variant part is not allowed", Def);
19322 Analyze (Variant_Part (Component_List (Def)));
19326 -- After completing the semantic analysis of the record definition,
19327 -- record components, both new and inherited, are accessible. Set their
19328 -- kind accordingly. Exclude malformed itypes from illegal declarations,
19329 -- whose Ekind may be void.
19331 Component := First_Entity (Current_Scope);
19332 while Present (Component) loop
19333 if Ekind (Component) = E_Void
19334 and then not Is_Itype (Component)
19336 Set_Ekind (Component, E_Component);
19337 Init_Component_Location (Component);
19340 if Has_Task (Etype (Component)) then
19344 if Ekind (Component) /= E_Component then
19347 -- Do not set Has_Controlled_Component on a class-wide equivalent
19348 -- type. See Make_CW_Equivalent_Type.
19350 elsif not Is_Class_Wide_Equivalent_Type (T)
19351 and then (Has_Controlled_Component (Etype (Component))
19352 or else (Chars (Component) /= Name_uParent
19353 and then Is_Controlled (Etype (Component))))
19355 Set_Has_Controlled_Component (T, True);
19356 Final_Storage_Only :=
19358 and then Finalize_Storage_Only (Etype (Component));
19359 Ctrl_Components := True;
19362 Next_Entity (Component);
19365 -- A Type is Finalize_Storage_Only only if all its controlled components
19368 if Ctrl_Components then
19369 Set_Finalize_Storage_Only (T, Final_Storage_Only);
19372 -- Place reference to end record on the proper entity, which may
19373 -- be a partial view.
19375 if Present (Def) then
19376 Process_End_Label (Def, 'e', Prev_T);
19378 end Record_Type_Definition;
19380 ------------------------
19381 -- Replace_Components --
19382 ------------------------
19384 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
19385 function Process (N : Node_Id) return Traverse_Result;
19391 function Process (N : Node_Id) return Traverse_Result is
19395 if Nkind (N) = N_Discriminant_Specification then
19396 Comp := First_Discriminant (Typ);
19397 while Present (Comp) loop
19398 if Chars (Comp) = Chars (Defining_Identifier (N)) then
19399 Set_Defining_Identifier (N, Comp);
19403 Next_Discriminant (Comp);
19406 elsif Nkind (N) = N_Component_Declaration then
19407 Comp := First_Component (Typ);
19408 while Present (Comp) loop
19409 if Chars (Comp) = Chars (Defining_Identifier (N)) then
19410 Set_Defining_Identifier (N, Comp);
19414 Next_Component (Comp);
19421 procedure Replace is new Traverse_Proc (Process);
19423 -- Start of processing for Replace_Components
19427 end Replace_Components;
19429 -------------------------------
19430 -- Set_Completion_Referenced --
19431 -------------------------------
19433 procedure Set_Completion_Referenced (E : Entity_Id) is
19435 -- If in main unit, mark entity that is a completion as referenced,
19436 -- warnings go on the partial view when needed.
19438 if In_Extended_Main_Source_Unit (E) then
19439 Set_Referenced (E);
19441 end Set_Completion_Referenced;
19443 ---------------------
19444 -- Set_Fixed_Range --
19445 ---------------------
19447 -- The range for fixed-point types is complicated by the fact that we
19448 -- do not know the exact end points at the time of the declaration. This
19449 -- is true for three reasons:
19451 -- A size clause may affect the fudging of the end-points
19452 -- A small clause may affect the values of the end-points
19453 -- We try to include the end-points if it does not affect the size
19455 -- This means that the actual end-points must be established at the point
19456 -- when the type is frozen. Meanwhile, we first narrow the range as
19457 -- permitted (so that it will fit if necessary in a small specified size),
19458 -- and then build a range subtree with these narrowed bounds.
19460 -- Set_Fixed_Range constructs the range from real literal values, and sets
19461 -- the range as the Scalar_Range of the given fixed-point type entity.
19463 -- The parent of this range is set to point to the entity so that it is
19464 -- properly hooked into the tree (unlike normal Scalar_Range entries for
19465 -- other scalar types, which are just pointers to the range in the
19466 -- original tree, this would otherwise be an orphan).
19468 -- The tree is left unanalyzed. When the type is frozen, the processing
19469 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
19470 -- analyzed, and uses this as an indication that it should complete
19471 -- work on the range (it will know the final small and size values).
19473 procedure Set_Fixed_Range
19479 S : constant Node_Id :=
19481 Low_Bound => Make_Real_Literal (Loc, Lo),
19482 High_Bound => Make_Real_Literal (Loc, Hi));
19484 Set_Scalar_Range (E, S);
19486 end Set_Fixed_Range;
19488 ----------------------------------
19489 -- Set_Scalar_Range_For_Subtype --
19490 ----------------------------------
19492 procedure Set_Scalar_Range_For_Subtype
19493 (Def_Id : Entity_Id;
19497 Kind : constant Entity_Kind := Ekind (Def_Id);
19500 -- Defend against previous error
19502 if Nkind (R) = N_Error then
19506 Set_Scalar_Range (Def_Id, R);
19508 -- We need to link the range into the tree before resolving it so
19509 -- that types that are referenced, including importantly the subtype
19510 -- itself, are properly frozen (Freeze_Expression requires that the
19511 -- expression be properly linked into the tree). Of course if it is
19512 -- already linked in, then we do not disturb the current link.
19514 if No (Parent (R)) then
19515 Set_Parent (R, Def_Id);
19518 -- Reset the kind of the subtype during analysis of the range, to
19519 -- catch possible premature use in the bounds themselves.
19521 Set_Ekind (Def_Id, E_Void);
19522 Process_Range_Expr_In_Decl (R, Subt);
19523 Set_Ekind (Def_Id, Kind);
19525 -- In ALFA, all subtypes should have a static range
19527 if Nkind (R) = N_Range
19528 and then not Is_Static_Range (R)
19530 Set_Is_In_ALFA (Def_Id, False);
19532 end Set_Scalar_Range_For_Subtype;
19534 --------------------------------------------------------
19535 -- Set_Stored_Constraint_From_Discriminant_Constraint --
19536 --------------------------------------------------------
19538 procedure Set_Stored_Constraint_From_Discriminant_Constraint
19542 -- Make sure set if encountered during Expand_To_Stored_Constraint
19544 Set_Stored_Constraint (E, No_Elist);
19546 -- Give it the right value
19548 if Is_Constrained (E) and then Has_Discriminants (E) then
19549 Set_Stored_Constraint (E,
19550 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
19552 end Set_Stored_Constraint_From_Discriminant_Constraint;
19554 -------------------------------------
19555 -- Signed_Integer_Type_Declaration --
19556 -------------------------------------
19558 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
19559 Implicit_Base : Entity_Id;
19560 Base_Typ : Entity_Id;
19563 Errs : Boolean := False;
19567 function Can_Derive_From (E : Entity_Id) return Boolean;
19568 -- Determine whether given bounds allow derivation from specified type
19570 procedure Check_Bound (Expr : Node_Id);
19571 -- Check bound to make sure it is integral and static. If not, post
19572 -- appropriate error message and set Errs flag
19574 ---------------------
19575 -- Can_Derive_From --
19576 ---------------------
19578 -- Note we check both bounds against both end values, to deal with
19579 -- strange types like ones with a range of 0 .. -12341234.
19581 function Can_Derive_From (E : Entity_Id) return Boolean is
19582 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
19583 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
19585 return Lo <= Lo_Val and then Lo_Val <= Hi
19587 Lo <= Hi_Val and then Hi_Val <= Hi;
19588 end Can_Derive_From;
19594 procedure Check_Bound (Expr : Node_Id) is
19596 -- If a range constraint is used as an integer type definition, each
19597 -- bound of the range must be defined by a static expression of some
19598 -- integer type, but the two bounds need not have the same integer
19599 -- type (Negative bounds are allowed.) (RM 3.5.4)
19601 if not Is_Integer_Type (Etype (Expr)) then
19603 ("integer type definition bounds must be of integer type", Expr);
19606 elsif not Is_OK_Static_Expression (Expr) then
19607 Flag_Non_Static_Expr
19608 ("non-static expression used for integer type bound!", Expr);
19611 -- The bounds are folded into literals, and we set their type to be
19612 -- universal, to avoid typing difficulties: we cannot set the type
19613 -- of the literal to the new type, because this would be a forward
19614 -- reference for the back end, and if the original type is user-
19615 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
19618 if Is_Entity_Name (Expr) then
19619 Fold_Uint (Expr, Expr_Value (Expr), True);
19622 Set_Etype (Expr, Universal_Integer);
19626 -- Start of processing for Signed_Integer_Type_Declaration
19629 -- Create an anonymous base type
19632 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
19634 -- Analyze and check the bounds, they can be of any integer type
19636 Lo := Low_Bound (Def);
19637 Hi := High_Bound (Def);
19639 -- Arbitrarily use Integer as the type if either bound had an error
19641 if Hi = Error or else Lo = Error then
19642 Base_Typ := Any_Integer;
19643 Set_Error_Posted (T, True);
19645 -- Here both bounds are OK expressions
19648 Analyze_And_Resolve (Lo, Any_Integer);
19649 Analyze_And_Resolve (Hi, Any_Integer);
19655 Hi := Type_High_Bound (Standard_Long_Long_Integer);
19656 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
19659 -- Find type to derive from
19661 Lo_Val := Expr_Value (Lo);
19662 Hi_Val := Expr_Value (Hi);
19664 if Can_Derive_From (Standard_Short_Short_Integer) then
19665 Base_Typ := Base_Type (Standard_Short_Short_Integer);
19667 elsif Can_Derive_From (Standard_Short_Integer) then
19668 Base_Typ := Base_Type (Standard_Short_Integer);
19670 elsif Can_Derive_From (Standard_Integer) then
19671 Base_Typ := Base_Type (Standard_Integer);
19673 elsif Can_Derive_From (Standard_Long_Integer) then
19674 Base_Typ := Base_Type (Standard_Long_Integer);
19676 elsif Can_Derive_From (Standard_Long_Long_Integer) then
19677 Base_Typ := Base_Type (Standard_Long_Long_Integer);
19680 Base_Typ := Base_Type (Standard_Long_Long_Integer);
19681 Error_Msg_N ("integer type definition bounds out of range", Def);
19682 Hi := Type_High_Bound (Standard_Long_Long_Integer);
19683 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
19687 -- Complete both implicit base and declared first subtype entities
19689 Set_Etype (Implicit_Base, Base_Typ);
19690 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
19691 Set_Size_Info (Implicit_Base, (Base_Typ));
19692 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
19693 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
19695 Set_Ekind (T, E_Signed_Integer_Subtype);
19696 Set_Etype (T, Implicit_Base);
19698 Set_Size_Info (T, (Implicit_Base));
19699 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
19700 Set_Scalar_Range (T, Def);
19701 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
19702 Set_Is_Constrained (T);
19703 Set_Is_In_ALFA (T);
19704 end Signed_Integer_Type_Declaration;