1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2014, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Debug; use Debug;
30 with Elists; use Elists;
31 with Einfo; use Einfo;
32 with Errout; use Errout;
33 with Eval_Fat; use Eval_Fat;
34 with Exp_Ch3; use Exp_Ch3;
35 with Exp_Ch9; use Exp_Ch9;
36 with Exp_Disp; use Exp_Disp;
37 with Exp_Dist; use Exp_Dist;
38 with Exp_Tss; use Exp_Tss;
39 with Exp_Util; use Exp_Util;
40 with Fname; use Fname;
41 with Freeze; use Freeze;
42 with Itypes; use Itypes;
43 with Layout; use Layout;
45 with Lib.Xref; use Lib.Xref;
46 with Namet; use Namet;
47 with Nmake; use Nmake;
49 with Restrict; use Restrict;
50 with Rident; use Rident;
51 with Rtsfind; use Rtsfind;
53 with Sem_Aux; use Sem_Aux;
54 with Sem_Case; use Sem_Case;
55 with Sem_Cat; use Sem_Cat;
56 with Sem_Ch6; use Sem_Ch6;
57 with Sem_Ch7; use Sem_Ch7;
58 with Sem_Ch8; use Sem_Ch8;
59 with Sem_Ch10; use Sem_Ch10;
60 with Sem_Ch13; use Sem_Ch13;
61 with Sem_Dim; use Sem_Dim;
62 with Sem_Disp; use Sem_Disp;
63 with Sem_Dist; use Sem_Dist;
64 with Sem_Elim; use Sem_Elim;
65 with Sem_Eval; use Sem_Eval;
66 with Sem_Mech; use Sem_Mech;
67 with Sem_Prag; use Sem_Prag;
68 with Sem_Res; use Sem_Res;
69 with Sem_Smem; use Sem_Smem;
70 with Sem_Type; use Sem_Type;
71 with Sem_Util; use Sem_Util;
72 with Sem_Warn; use Sem_Warn;
73 with Stand; use Stand;
74 with Sinfo; use Sinfo;
75 with Sinput; use Sinput;
76 with Snames; use Snames;
77 with Targparm; use Targparm;
78 with Tbuild; use Tbuild;
79 with Ttypes; use Ttypes;
80 with Uintp; use Uintp;
81 with Urealp; use Urealp;
83 package body Sem_Ch3 is
85 -----------------------
86 -- Local Subprograms --
87 -----------------------
89 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
90 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
91 -- abstract interface types implemented by a record type or a derived
94 procedure Analyze_Object_Contract (Obj_Id : Entity_Id);
95 -- Analyze all delayed pragmas chained on the contract of object Obj_Id as
96 -- if they appeared at the end of the declarative region. The pragmas to be
104 procedure Build_Derived_Type
106 Parent_Type : Entity_Id;
107 Derived_Type : Entity_Id;
108 Is_Completion : Boolean;
109 Derive_Subps : Boolean := True);
110 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
111 -- the N_Full_Type_Declaration node containing the derived type definition.
112 -- Parent_Type is the entity for the parent type in the derived type
113 -- definition and Derived_Type the actual derived type. Is_Completion must
114 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
115 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
116 -- completion of a private type declaration. If Is_Completion is set to
117 -- True, N is the completion of a private type declaration and Derived_Type
118 -- is different from the defining identifier inside N (i.e. Derived_Type /=
119 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
120 -- subprograms should be derived. The only case where this parameter is
121 -- False is when Build_Derived_Type is recursively called to process an
122 -- implicit derived full type for a type derived from a private type (in
123 -- that case the subprograms must only be derived for the private view of
126 -- ??? These flags need a bit of re-examination and re-documentation:
127 -- ??? are they both necessary (both seem related to the recursion)?
129 procedure Build_Derived_Access_Type
131 Parent_Type : Entity_Id;
132 Derived_Type : Entity_Id);
133 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
134 -- create an implicit base if the parent type is constrained or if the
135 -- subtype indication has a constraint.
137 procedure Build_Derived_Array_Type
139 Parent_Type : Entity_Id;
140 Derived_Type : Entity_Id);
141 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
142 -- create an implicit base if the parent type is constrained or if the
143 -- subtype indication has a constraint.
145 procedure Build_Derived_Concurrent_Type
147 Parent_Type : Entity_Id;
148 Derived_Type : Entity_Id);
149 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
150 -- protected type, inherit entries and protected subprograms, check
151 -- legality of discriminant constraints if any.
153 procedure Build_Derived_Enumeration_Type
155 Parent_Type : Entity_Id;
156 Derived_Type : Entity_Id);
157 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
158 -- type, we must create a new list of literals. Types derived from
159 -- Character and [Wide_]Wide_Character are special-cased.
161 procedure Build_Derived_Numeric_Type
163 Parent_Type : Entity_Id;
164 Derived_Type : Entity_Id);
165 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
166 -- an anonymous base type, and propagate constraint to subtype if needed.
168 procedure Build_Derived_Private_Type
170 Parent_Type : Entity_Id;
171 Derived_Type : Entity_Id;
172 Is_Completion : Boolean;
173 Derive_Subps : Boolean := True);
174 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
175 -- because the parent may or may not have a completion, and the derivation
176 -- may itself be a completion.
178 procedure Build_Derived_Record_Type
180 Parent_Type : Entity_Id;
181 Derived_Type : Entity_Id;
182 Derive_Subps : Boolean := True);
183 -- Subsidiary procedure used for tagged and untagged record types
184 -- by Build_Derived_Type and Analyze_Private_Extension_Declaration.
185 -- All parameters are as in Build_Derived_Type except that N, in
186 -- addition to being an N_Full_Type_Declaration node, can also be an
187 -- N_Private_Extension_Declaration node. See the definition of this routine
188 -- for much more info. Derive_Subps indicates whether subprograms should be
189 -- derived from the parent type. The only case where Derive_Subps is False
190 -- is for an implicit derived full type for a type derived from a private
191 -- type (see Build_Derived_Type).
193 procedure Build_Discriminal (Discrim : Entity_Id);
194 -- Create the discriminal corresponding to discriminant Discrim, that is
195 -- the parameter corresponding to Discrim to be used in initialization
196 -- procedures for the type where Discrim is a discriminant. Discriminals
197 -- are not used during semantic analysis, and are not fully defined
198 -- entities until expansion. Thus they are not given a scope until
199 -- initialization procedures are built.
201 function Build_Discriminant_Constraints
204 Derived_Def : Boolean := False) return Elist_Id;
205 -- Validate discriminant constraints and return the list of the constraints
206 -- in order of discriminant declarations, where T is the discriminated
207 -- unconstrained type. Def is the N_Subtype_Indication node where the
208 -- discriminants constraints for T are specified. Derived_Def is True
209 -- when building the discriminant constraints in a derived type definition
210 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
211 -- type and Def is the constraint "(xxx)" on T and this routine sets the
212 -- Corresponding_Discriminant field of the discriminants in the derived
213 -- type D to point to the corresponding discriminants in the parent type T.
215 procedure Build_Discriminated_Subtype
219 Related_Nod : Node_Id;
220 For_Access : Boolean := False);
221 -- Subsidiary procedure to Constrain_Discriminated_Type and to
222 -- Process_Incomplete_Dependents. Given
224 -- T (a possibly discriminated base type)
225 -- Def_Id (a very partially built subtype for T),
227 -- the call completes Def_Id to be the appropriate E_*_Subtype.
229 -- The Elist is the list of discriminant constraints if any (it is set
230 -- to No_Elist if T is not a discriminated type, and to an empty list if
231 -- T has discriminants but there are no discriminant constraints). The
232 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
233 -- The For_Access says whether or not this subtype is really constraining
234 -- an access type. That is its sole purpose is the designated type of an
235 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
236 -- is built to avoid freezing T when the access subtype is frozen.
238 function Build_Scalar_Bound
241 Der_T : Entity_Id) return Node_Id;
242 -- The bounds of a derived scalar type are conversions of the bounds of
243 -- the parent type. Optimize the representation if the bounds are literals.
244 -- Needs a more complete spec--what are the parameters exactly, and what
245 -- exactly is the returned value, and how is Bound affected???
247 procedure Build_Underlying_Full_View
251 -- If the completion of a private type is itself derived from a private
252 -- type, or if the full view of a private subtype is itself private, the
253 -- back-end has no way to compute the actual size of this type. We build
254 -- an internal subtype declaration of the proper parent type to convey
255 -- this information. This extra mechanism is needed because a full
256 -- view cannot itself have a full view (it would get clobbered during
259 procedure Check_Access_Discriminant_Requires_Limited
262 -- Check the restriction that the type to which an access discriminant
263 -- belongs must be a concurrent type or a descendant of a type with
264 -- the reserved word 'limited' in its declaration.
266 procedure Check_Anonymous_Access_Components
270 Comp_List : Node_Id);
271 -- Ada 2005 AI-382: an access component in a record definition can refer to
272 -- the enclosing record, in which case it denotes the type itself, and not
273 -- the current instance of the type. We create an anonymous access type for
274 -- the component, and flag it as an access to a component, so accessibility
275 -- checks are properly performed on it. The declaration of the access type
276 -- is placed ahead of that of the record to prevent order-of-elaboration
277 -- circularity issues in Gigi. We create an incomplete type for the record
278 -- declaration, which is the designated type of the anonymous access.
280 procedure Check_Delta_Expression (E : Node_Id);
281 -- Check that the expression represented by E is suitable for use as a
282 -- delta expression, i.e. it is of real type and is static.
284 procedure Check_Digits_Expression (E : Node_Id);
285 -- Check that the expression represented by E is suitable for use as a
286 -- digits expression, i.e. it is of integer type, positive and static.
288 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
289 -- Validate the initialization of an object declaration. T is the required
290 -- type, and Exp is the initialization expression.
292 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
293 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
295 procedure Check_Or_Process_Discriminants
298 Prev : Entity_Id := Empty);
299 -- If N is the full declaration of the completion T of an incomplete or
300 -- private type, check its discriminants (which are already known to be
301 -- conformant with those of the partial view, see Find_Type_Name),
302 -- otherwise process them. Prev is the entity of the partial declaration,
305 procedure Check_Real_Bound (Bound : Node_Id);
306 -- Check given bound for being of real type and static. If not, post an
307 -- appropriate message, and rewrite the bound with the real literal zero.
309 procedure Constant_Redeclaration
313 -- Various checks on legality of full declaration of deferred constant.
314 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
315 -- node. The caller has not yet set any attributes of this entity.
317 function Contain_Interface
319 Ifaces : Elist_Id) return Boolean;
320 -- Ada 2005: Determine whether Iface is present in the list Ifaces
322 procedure Convert_Scalar_Bounds
324 Parent_Type : Entity_Id;
325 Derived_Type : Entity_Id;
327 -- For derived scalar types, convert the bounds in the type definition to
328 -- the derived type, and complete their analysis. Given a constraint of the
329 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
330 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
331 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
332 -- subtype are conversions of those bounds to the derived_type, so that
333 -- their typing is consistent.
335 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
336 -- Copies attributes from array base type T2 to array base type T1. Copies
337 -- only attributes that apply to base types, but not subtypes.
339 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
340 -- Copies attributes from array subtype T2 to array subtype T1. Copies
341 -- attributes that apply to both subtypes and base types.
343 procedure Create_Constrained_Components
347 Constraints : Elist_Id);
348 -- Build the list of entities for a constrained discriminated record
349 -- subtype. If a component depends on a discriminant, replace its subtype
350 -- using the discriminant values in the discriminant constraint. Subt
351 -- is the defining identifier for the subtype whose list of constrained
352 -- entities we will create. Decl_Node is the type declaration node where
353 -- we will attach all the itypes created. Typ is the base discriminated
354 -- type for the subtype Subt. Constraints is the list of discriminant
355 -- constraints for Typ.
357 function Constrain_Component_Type
359 Constrained_Typ : Entity_Id;
360 Related_Node : Node_Id;
362 Constraints : Elist_Id) return Entity_Id;
363 -- Given a discriminated base type Typ, a list of discriminant constraints,
364 -- Constraints, for Typ and a component Comp of Typ, create and return the
365 -- type corresponding to Etype (Comp) where all discriminant references
366 -- are replaced with the corresponding constraint. If Etype (Comp) contains
367 -- no discriminant references then it is returned as-is. Constrained_Typ
368 -- is the final constrained subtype to which the constrained component
369 -- belongs. Related_Node is the node where we attach all created itypes.
371 procedure Constrain_Access
372 (Def_Id : in out Entity_Id;
374 Related_Nod : Node_Id);
375 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
376 -- an anonymous type created for a subtype indication. In that case it is
377 -- created in the procedure and attached to Related_Nod.
379 procedure Constrain_Array
380 (Def_Id : in out Entity_Id;
382 Related_Nod : Node_Id;
383 Related_Id : Entity_Id;
385 -- Apply a list of index constraints to an unconstrained array type. The
386 -- first parameter is the entity for the resulting subtype. A value of
387 -- Empty for Def_Id indicates that an implicit type must be created, but
388 -- creation is delayed (and must be done by this procedure) because other
389 -- subsidiary implicit types must be created first (which is why Def_Id
390 -- is an in/out parameter). The second parameter is a subtype indication
391 -- node for the constrained array to be created (e.g. something of the
392 -- form string (1 .. 10)). Related_Nod gives the place where this type
393 -- has to be inserted in the tree. The Related_Id and Suffix parameters
394 -- are used to build the associated Implicit type name.
396 procedure Constrain_Concurrent
397 (Def_Id : in out Entity_Id;
399 Related_Nod : Node_Id;
400 Related_Id : Entity_Id;
402 -- Apply list of discriminant constraints to an unconstrained concurrent
405 -- SI is the N_Subtype_Indication node containing the constraint and
406 -- the unconstrained type to constrain.
408 -- Def_Id is the entity for the resulting constrained subtype. A value
409 -- of Empty for Def_Id indicates that an implicit type must be created,
410 -- but creation is delayed (and must be done by this procedure) because
411 -- other subsidiary implicit types must be created first (which is why
412 -- Def_Id is an in/out parameter).
414 -- Related_Nod gives the place where this type has to be inserted
417 -- The last two arguments are used to create its external name if needed.
419 function Constrain_Corresponding_Record
420 (Prot_Subt : Entity_Id;
421 Corr_Rec : Entity_Id;
422 Related_Nod : Node_Id) return Entity_Id;
423 -- When constraining a protected type or task type with discriminants,
424 -- constrain the corresponding record with the same discriminant values.
426 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
427 -- Constrain a decimal fixed point type with a digits constraint and/or a
428 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
430 procedure Constrain_Discriminated_Type
433 Related_Nod : Node_Id;
434 For_Access : Boolean := False);
435 -- Process discriminant constraints of composite type. Verify that values
436 -- have been provided for all discriminants, that the original type is
437 -- unconstrained, and that the types of the supplied expressions match
438 -- the discriminant types. The first three parameters are like in routine
439 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
442 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
443 -- Constrain an enumeration type with a range constraint. This is identical
444 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
446 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
447 -- Constrain a floating point type with either a digits constraint
448 -- and/or a range constraint, building a E_Floating_Point_Subtype.
450 procedure Constrain_Index
453 Related_Nod : Node_Id;
454 Related_Id : Entity_Id;
457 -- Process an index constraint S in a constrained array declaration. The
458 -- constraint can be a subtype name, or a range with or without an explicit
459 -- subtype mark. The index is the corresponding index of the unconstrained
460 -- array. The Related_Id and Suffix parameters are used to build the
461 -- associated Implicit type name.
463 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
464 -- Build subtype of a signed or modular integer type
466 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
467 -- Constrain an ordinary fixed point type with a range constraint, and
468 -- build an E_Ordinary_Fixed_Point_Subtype entity.
470 procedure Copy_And_Swap (Priv, Full : Entity_Id);
471 -- Copy the Priv entity into the entity of its full declaration then swap
472 -- the two entities in such a manner that the former private type is now
473 -- seen as a full type.
475 procedure Decimal_Fixed_Point_Type_Declaration
478 -- Create a new decimal fixed point type, and apply the constraint to
479 -- obtain a subtype of this new type.
481 procedure Complete_Private_Subtype
484 Full_Base : Entity_Id;
485 Related_Nod : Node_Id);
486 -- Complete the implicit full view of a private subtype by setting the
487 -- appropriate semantic fields. If the full view of the parent is a record
488 -- type, build constrained components of subtype.
490 procedure Derive_Progenitor_Subprograms
491 (Parent_Type : Entity_Id;
492 Tagged_Type : Entity_Id);
493 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
494 -- operations of progenitors of Tagged_Type, and replace the subsidiary
495 -- subtypes with Tagged_Type, to build the specs of the inherited interface
496 -- primitives. The derived primitives are aliased to those of the
497 -- interface. This routine takes care also of transferring to the full view
498 -- subprograms associated with the partial view of Tagged_Type that cover
499 -- interface primitives.
501 procedure Derived_Standard_Character
503 Parent_Type : Entity_Id;
504 Derived_Type : Entity_Id);
505 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
506 -- derivations from types Standard.Character and Standard.Wide_Character.
508 procedure Derived_Type_Declaration
511 Is_Completion : Boolean);
512 -- Process a derived type declaration. Build_Derived_Type is invoked
513 -- to process the actual derived type definition. Parameters N and
514 -- Is_Completion have the same meaning as in Build_Derived_Type.
515 -- T is the N_Defining_Identifier for the entity defined in the
516 -- N_Full_Type_Declaration node N, that is T is the derived type.
518 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
519 -- Insert each literal in symbol table, as an overloadable identifier. Each
520 -- enumeration type is mapped into a sequence of integers, and each literal
521 -- is defined as a constant with integer value. If any of the literals are
522 -- character literals, the type is a character type, which means that
523 -- strings are legal aggregates for arrays of components of the type.
525 function Expand_To_Stored_Constraint
527 Constraint : Elist_Id) return Elist_Id;
528 -- Given a constraint (i.e. a list of expressions) on the discriminants of
529 -- Typ, expand it into a constraint on the stored discriminants and return
530 -- the new list of expressions constraining the stored discriminants.
532 function Find_Type_Of_Object
534 Related_Nod : Node_Id) return Entity_Id;
535 -- Get type entity for object referenced by Obj_Def, attaching the
536 -- implicit types generated to Related_Nod
538 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
539 -- Create a new float and apply the constraint to obtain subtype of it
541 function Has_Range_Constraint (N : Node_Id) return Boolean;
542 -- Given an N_Subtype_Indication node N, return True if a range constraint
543 -- is present, either directly, or as part of a digits or delta constraint.
544 -- In addition, a digits constraint in the decimal case returns True, since
545 -- it establishes a default range if no explicit range is present.
547 function Inherit_Components
549 Parent_Base : Entity_Id;
550 Derived_Base : Entity_Id;
552 Inherit_Discr : Boolean;
553 Discs : Elist_Id) return Elist_Id;
554 -- Called from Build_Derived_Record_Type to inherit the components of
555 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
556 -- For more information on derived types and component inheritance please
557 -- consult the comment above the body of Build_Derived_Record_Type.
559 -- N is the original derived type declaration
561 -- Is_Tagged is set if we are dealing with tagged types
563 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
564 -- Parent_Base, otherwise no discriminants are inherited.
566 -- Discs gives the list of constraints that apply to Parent_Base in the
567 -- derived type declaration. If Discs is set to No_Elist, then we have
568 -- the following situation:
570 -- type Parent (D1..Dn : ..) is [tagged] record ...;
571 -- type Derived is new Parent [with ...];
573 -- which gets treated as
575 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
577 -- For untagged types the returned value is an association list. The list
578 -- starts from the association (Parent_Base => Derived_Base), and then it
579 -- contains a sequence of the associations of the form
581 -- (Old_Component => New_Component),
583 -- where Old_Component is the Entity_Id of a component in Parent_Base and
584 -- New_Component is the Entity_Id of the corresponding component in
585 -- Derived_Base. For untagged records, this association list is needed when
586 -- copying the record declaration for the derived base. In the tagged case
587 -- the value returned is irrelevant.
589 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id);
590 -- Propagate static and dynamic predicate flags from a parent to the
591 -- subtype in a subtype declaration with and without constraints.
593 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean;
594 -- Subsidiary to Check_Abstract_Overriding and Derive_Subprogram.
595 -- Determine whether subprogram Subp is a procedure subject to pragma
596 -- Extensions_Visible with value False and has at least one controlling
597 -- parameter of mode OUT.
599 function Is_Valid_Constraint_Kind
601 Constraint_Kind : Node_Kind) return Boolean;
602 -- Returns True if it is legal to apply the given kind of constraint to the
603 -- given kind of type (index constraint to an array type, for example).
605 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
606 -- Create new modular type. Verify that modulus is in bounds
608 procedure New_Concatenation_Op (Typ : Entity_Id);
609 -- Create an abbreviated declaration for an operator in order to
610 -- materialize concatenation on array types.
612 procedure Ordinary_Fixed_Point_Type_Declaration
615 -- Create a new ordinary fixed point type, and apply the constraint to
616 -- obtain subtype of it.
618 procedure Prepare_Private_Subtype_Completion
620 Related_Nod : Node_Id);
621 -- Id is a subtype of some private type. Creates the full declaration
622 -- associated with Id whenever possible, i.e. when the full declaration
623 -- of the base type is already known. Records each subtype into
624 -- Private_Dependents of the base type.
626 procedure Process_Incomplete_Dependents
630 -- Process all entities that depend on an incomplete type. There include
631 -- subtypes, subprogram types that mention the incomplete type in their
632 -- profiles, and subprogram with access parameters that designate the
635 -- Inc_T is the defining identifier of an incomplete type declaration, its
636 -- Ekind is E_Incomplete_Type.
638 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
640 -- Full_T is N's defining identifier.
642 -- Subtypes of incomplete types with discriminants are completed when the
643 -- parent type is. This is simpler than private subtypes, because they can
644 -- only appear in the same scope, and there is no need to exchange views.
645 -- Similarly, access_to_subprogram types may have a parameter or a return
646 -- type that is an incomplete type, and that must be replaced with the
649 -- If the full type is tagged, subprogram with access parameters that
650 -- designated the incomplete may be primitive operations of the full type,
651 -- and have to be processed accordingly.
653 procedure Process_Real_Range_Specification (Def : Node_Id);
654 -- Given the type definition for a real type, this procedure processes and
655 -- checks the real range specification of this type definition if one is
656 -- present. If errors are found, error messages are posted, and the
657 -- Real_Range_Specification of Def is reset to Empty.
659 procedure Propagate_Default_Init_Cond_Attributes
660 (From_Typ : Entity_Id;
662 Parent_To_Derivation : Boolean := False;
663 Private_To_Full_View : Boolean := False);
664 -- Subsidiary to routines Build_Derived_Type and Process_Full_View. Inherit
665 -- all attributes related to pragma Default_Initial_Condition from From_Typ
666 -- to To_Typ. Flag Parent_To_Derivation should be set when the context is
667 -- the creation of a derived type. Flag Private_To_Full_View should be set
668 -- when processing both views of a private type.
670 procedure Record_Type_Declaration
674 -- Process a record type declaration (for both untagged and tagged
675 -- records). Parameters T and N are exactly like in procedure
676 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
677 -- for this routine. If this is the completion of an incomplete type
678 -- declaration, Prev is the entity of the incomplete declaration, used for
679 -- cross-referencing. Otherwise Prev = T.
681 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
682 -- This routine is used to process the actual record type definition (both
683 -- for untagged and tagged records). Def is a record type definition node.
684 -- This procedure analyzes the components in this record type definition.
685 -- Prev_T is the entity for the enclosing record type. It is provided so
686 -- that its Has_Task flag can be set if any of the component have Has_Task
687 -- set. If the declaration is the completion of an incomplete type
688 -- declaration, Prev_T is the original incomplete type, whose full view is
691 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
692 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
693 -- build a copy of the declaration tree of the parent, and we create
694 -- independently the list of components for the derived type. Semantic
695 -- information uses the component entities, but record representation
696 -- clauses are validated on the declaration tree. This procedure replaces
697 -- discriminants and components in the declaration with those that have
698 -- been created by Inherit_Components.
700 procedure Set_Fixed_Range
705 -- Build a range node with the given bounds and set it as the Scalar_Range
706 -- of the given fixed-point type entity. Loc is the source location used
707 -- for the constructed range. See body for further details.
709 procedure Set_Scalar_Range_For_Subtype
713 -- This routine is used to set the scalar range field for a subtype given
714 -- Def_Id, the entity for the subtype, and R, the range expression for the
715 -- scalar range. Subt provides the parent subtype to be used to analyze,
716 -- resolve, and check the given range.
718 procedure Set_Default_SSO (T : Entity_Id);
719 -- T is the entity for an array or record being declared. This procedure
720 -- sets the flags SSO_Set_Low_By_Default/SSO_Set_High_By_Default according
721 -- to the setting of Opt.Default_SSO.
723 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
724 -- Create a new signed integer entity, and apply the constraint to obtain
725 -- the required first named subtype of this type.
727 procedure Set_Stored_Constraint_From_Discriminant_Constraint
729 -- E is some record type. This routine computes E's Stored_Constraint
730 -- from its Discriminant_Constraint.
732 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
733 -- Check that an entity in a list of progenitors is an interface,
734 -- emit error otherwise.
736 -----------------------
737 -- Access_Definition --
738 -----------------------
740 function Access_Definition
741 (Related_Nod : Node_Id;
742 N : Node_Id) return Entity_Id
744 Anon_Type : Entity_Id;
745 Anon_Scope : Entity_Id;
746 Desig_Type : Entity_Id;
747 Enclosing_Prot_Type : Entity_Id := Empty;
750 Check_SPARK_05_Restriction ("access type is not allowed", N);
752 if Is_Entry (Current_Scope)
753 and then Is_Task_Type (Etype (Scope (Current_Scope)))
755 Error_Msg_N ("task entries cannot have access parameters", N);
759 -- Ada 2005: For an object declaration the corresponding anonymous
760 -- type is declared in the current scope.
762 -- If the access definition is the return type of another access to
763 -- function, scope is the current one, because it is the one of the
764 -- current type declaration, except for the pathological case below.
766 if Nkind_In (Related_Nod, N_Object_Declaration,
767 N_Access_Function_Definition)
769 Anon_Scope := Current_Scope;
771 -- A pathological case: function returning access functions that
772 -- return access functions, etc. Each anonymous access type created
773 -- is in the enclosing scope of the outermost function.
780 while Nkind_In (Par, N_Access_Function_Definition,
786 if Nkind (Par) = N_Function_Specification then
787 Anon_Scope := Scope (Defining_Entity (Par));
791 -- For the anonymous function result case, retrieve the scope of the
792 -- function specification's associated entity rather than using the
793 -- current scope. The current scope will be the function itself if the
794 -- formal part is currently being analyzed, but will be the parent scope
795 -- in the case of a parameterless function, and we always want to use
796 -- the function's parent scope. Finally, if the function is a child
797 -- unit, we must traverse the tree to retrieve the proper entity.
799 elsif Nkind (Related_Nod) = N_Function_Specification
800 and then Nkind (Parent (N)) /= N_Parameter_Specification
802 -- If the current scope is a protected type, the anonymous access
803 -- is associated with one of the protected operations, and must
804 -- be available in the scope that encloses the protected declaration.
805 -- Otherwise the type is in the scope enclosing the subprogram.
807 -- If the function has formals, The return type of a subprogram
808 -- declaration is analyzed in the scope of the subprogram (see
809 -- Process_Formals) and thus the protected type, if present, is
810 -- the scope of the current function scope.
812 if Ekind (Current_Scope) = E_Protected_Type then
813 Enclosing_Prot_Type := Current_Scope;
815 elsif Ekind (Current_Scope) = E_Function
816 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
818 Enclosing_Prot_Type := Scope (Current_Scope);
821 if Present (Enclosing_Prot_Type) then
822 Anon_Scope := Scope (Enclosing_Prot_Type);
825 Anon_Scope := Scope (Defining_Entity (Related_Nod));
828 -- For an access type definition, if the current scope is a child
829 -- unit it is the scope of the type.
831 elsif Is_Compilation_Unit (Current_Scope) then
832 Anon_Scope := Current_Scope;
834 -- For access formals, access components, and access discriminants, the
835 -- scope is that of the enclosing declaration,
838 Anon_Scope := Scope (Current_Scope);
843 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
846 and then Ada_Version >= Ada_2005
848 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
851 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
852 -- the corresponding semantic routine
854 if Present (Access_To_Subprogram_Definition (N)) then
856 -- Compiler runtime units are compiled in Ada 2005 mode when building
857 -- the runtime library but must also be compilable in Ada 95 mode
858 -- (when bootstrapping the compiler).
860 Check_Compiler_Unit ("anonymous access to subprogram", N);
862 Access_Subprogram_Declaration
863 (T_Name => Anon_Type,
864 T_Def => Access_To_Subprogram_Definition (N));
866 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
868 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
870 Set_Ekind (Anon_Type, E_Anonymous_Access_Subprogram_Type);
873 Set_Can_Use_Internal_Rep
874 (Anon_Type, not Always_Compatible_Rep_On_Target);
876 -- If the anonymous access is associated with a protected operation,
877 -- create a reference to it after the enclosing protected definition
878 -- because the itype will be used in the subsequent bodies.
880 if Ekind (Current_Scope) = E_Protected_Type then
881 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
887 Find_Type (Subtype_Mark (N));
888 Desig_Type := Entity (Subtype_Mark (N));
890 Set_Directly_Designated_Type (Anon_Type, Desig_Type);
891 Set_Etype (Anon_Type, Anon_Type);
893 -- Make sure the anonymous access type has size and alignment fields
894 -- set, as required by gigi. This is necessary in the case of the
895 -- Task_Body_Procedure.
897 if not Has_Private_Component (Desig_Type) then
898 Layout_Type (Anon_Type);
901 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
902 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
903 -- the null value is allowed. In Ada 95 the null value is never allowed.
905 if Ada_Version >= Ada_2005 then
906 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
908 Set_Can_Never_Be_Null (Anon_Type, True);
911 -- The anonymous access type is as public as the discriminated type or
912 -- subprogram that defines it. It is imported (for back-end purposes)
913 -- if the designated type is.
915 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
917 -- Ada 2005 (AI-231): Propagate the access-constant attribute
919 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
921 -- The context is either a subprogram declaration, object declaration,
922 -- or an access discriminant, in a private or a full type declaration.
923 -- In the case of a subprogram, if the designated type is incomplete,
924 -- the operation will be a primitive operation of the full type, to be
925 -- updated subsequently. If the type is imported through a limited_with
926 -- clause, the subprogram is not a primitive operation of the type
927 -- (which is declared elsewhere in some other scope).
929 if Ekind (Desig_Type) = E_Incomplete_Type
930 and then not From_Limited_With (Desig_Type)
931 and then Is_Overloadable (Current_Scope)
933 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
934 Set_Has_Delayed_Freeze (Current_Scope);
937 -- Ada 2005: If the designated type is an interface that may contain
938 -- tasks, create a Master entity for the declaration. This must be done
939 -- before expansion of the full declaration, because the declaration may
940 -- include an expression that is an allocator, whose expansion needs the
941 -- proper Master for the created tasks.
943 if Nkind (Related_Nod) = N_Object_Declaration and then Expander_Active
945 if Is_Interface (Desig_Type) and then Is_Limited_Record (Desig_Type)
947 Build_Class_Wide_Master (Anon_Type);
949 -- Similarly, if the type is an anonymous access that designates
950 -- tasks, create a master entity for it in the current context.
952 elsif Has_Task (Desig_Type) and then Comes_From_Source (Related_Nod)
954 Build_Master_Entity (Defining_Identifier (Related_Nod));
955 Build_Master_Renaming (Anon_Type);
959 -- For a private component of a protected type, it is imperative that
960 -- the back-end elaborate the type immediately after the protected
961 -- declaration, because this type will be used in the declarations
962 -- created for the component within each protected body, so we must
963 -- create an itype reference for it now.
965 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
966 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
968 -- Similarly, if the access definition is the return result of a
969 -- function, create an itype reference for it because it will be used
970 -- within the function body. For a regular function that is not a
971 -- compilation unit, insert reference after the declaration. For a
972 -- protected operation, insert it after the enclosing protected type
973 -- declaration. In either case, do not create a reference for a type
974 -- obtained through a limited_with clause, because this would introduce
975 -- semantic dependencies.
977 -- Similarly, do not create a reference if the designated type is a
978 -- generic formal, because no use of it will reach the backend.
980 elsif Nkind (Related_Nod) = N_Function_Specification
981 and then not From_Limited_With (Desig_Type)
982 and then not Is_Generic_Type (Desig_Type)
984 if Present (Enclosing_Prot_Type) then
985 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
987 elsif Is_List_Member (Parent (Related_Nod))
988 and then Nkind (Parent (N)) /= N_Parameter_Specification
990 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
993 -- Finally, create an itype reference for an object declaration of an
994 -- anonymous access type. This is strictly necessary only for deferred
995 -- constants, but in any case will avoid out-of-scope problems in the
998 elsif Nkind (Related_Nod) = N_Object_Declaration then
999 Build_Itype_Reference (Anon_Type, Related_Nod);
1003 end Access_Definition;
1005 -----------------------------------
1006 -- Access_Subprogram_Declaration --
1007 -----------------------------------
1009 procedure Access_Subprogram_Declaration
1010 (T_Name : Entity_Id;
1013 procedure Check_For_Premature_Usage (Def : Node_Id);
1014 -- Check that type T_Name is not used, directly or recursively, as a
1015 -- parameter or a return type in Def. Def is either a subtype, an
1016 -- access_definition, or an access_to_subprogram_definition.
1018 -------------------------------
1019 -- Check_For_Premature_Usage --
1020 -------------------------------
1022 procedure Check_For_Premature_Usage (Def : Node_Id) is
1026 -- Check for a subtype mark
1028 if Nkind (Def) in N_Has_Etype then
1029 if Etype (Def) = T_Name then
1031 ("type& cannot be used before end of its declaration", Def);
1034 -- If this is not a subtype, then this is an access_definition
1036 elsif Nkind (Def) = N_Access_Definition then
1037 if Present (Access_To_Subprogram_Definition (Def)) then
1038 Check_For_Premature_Usage
1039 (Access_To_Subprogram_Definition (Def));
1041 Check_For_Premature_Usage (Subtype_Mark (Def));
1044 -- The only cases left are N_Access_Function_Definition and
1045 -- N_Access_Procedure_Definition.
1048 if Present (Parameter_Specifications (Def)) then
1049 Param := First (Parameter_Specifications (Def));
1050 while Present (Param) loop
1051 Check_For_Premature_Usage (Parameter_Type (Param));
1052 Param := Next (Param);
1056 if Nkind (Def) = N_Access_Function_Definition then
1057 Check_For_Premature_Usage (Result_Definition (Def));
1060 end Check_For_Premature_Usage;
1064 Formals : constant List_Id := Parameter_Specifications (T_Def);
1067 Desig_Type : constant Entity_Id :=
1068 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1070 -- Start of processing for Access_Subprogram_Declaration
1073 Check_SPARK_05_Restriction ("access type is not allowed", T_Def);
1075 -- Associate the Itype node with the inner full-type declaration or
1076 -- subprogram spec or entry body. This is required to handle nested
1077 -- anonymous declarations. For example:
1080 -- (X : access procedure
1081 -- (Y : access procedure
1084 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1085 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1086 N_Private_Type_Declaration,
1087 N_Private_Extension_Declaration,
1088 N_Procedure_Specification,
1089 N_Function_Specification,
1093 Nkind_In (D_Ityp, N_Object_Declaration,
1094 N_Object_Renaming_Declaration,
1095 N_Formal_Object_Declaration,
1096 N_Formal_Type_Declaration,
1097 N_Task_Type_Declaration,
1098 N_Protected_Type_Declaration))
1100 D_Ityp := Parent (D_Ityp);
1101 pragma Assert (D_Ityp /= Empty);
1104 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1106 if Nkind_In (D_Ityp, N_Procedure_Specification,
1107 N_Function_Specification)
1109 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1111 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1112 N_Object_Declaration,
1113 N_Object_Renaming_Declaration,
1114 N_Formal_Type_Declaration)
1116 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1119 if Nkind (T_Def) = N_Access_Function_Definition then
1120 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1122 Acc : constant Node_Id := Result_Definition (T_Def);
1125 if Present (Access_To_Subprogram_Definition (Acc))
1127 Protected_Present (Access_To_Subprogram_Definition (Acc))
1131 Replace_Anonymous_Access_To_Protected_Subprogram
1137 Access_Definition (T_Def, Result_Definition (T_Def)));
1142 Analyze (Result_Definition (T_Def));
1145 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1148 -- If a null exclusion is imposed on the result type, then
1149 -- create a null-excluding itype (an access subtype) and use
1150 -- it as the function's Etype.
1152 if Is_Access_Type (Typ)
1153 and then Null_Exclusion_In_Return_Present (T_Def)
1155 Set_Etype (Desig_Type,
1156 Create_Null_Excluding_Itype
1158 Related_Nod => T_Def,
1159 Scope_Id => Current_Scope));
1162 if From_Limited_With (Typ) then
1164 -- AI05-151: Incomplete types are allowed in all basic
1165 -- declarations, including access to subprograms.
1167 if Ada_Version >= Ada_2012 then
1172 ("illegal use of incomplete type&",
1173 Result_Definition (T_Def), Typ);
1176 elsif Ekind (Current_Scope) = E_Package
1177 and then In_Private_Part (Current_Scope)
1179 if Ekind (Typ) = E_Incomplete_Type then
1180 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1182 elsif Is_Class_Wide_Type (Typ)
1183 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1186 (Desig_Type, Private_Dependents (Etype (Typ)));
1190 Set_Etype (Desig_Type, Typ);
1195 if not (Is_Type (Etype (Desig_Type))) then
1197 ("expect type in function specification",
1198 Result_Definition (T_Def));
1202 Set_Etype (Desig_Type, Standard_Void_Type);
1205 if Present (Formals) then
1206 Push_Scope (Desig_Type);
1208 -- Some special tests here. These special tests can be removed
1209 -- if and when Itypes always have proper parent pointers to their
1212 -- Special test 1) Link defining_identifier of formals. Required by
1213 -- First_Formal to provide its functionality.
1219 F := First (Formals);
1221 -- In ASIS mode, the access_to_subprogram may be analyzed twice,
1222 -- when it is part of an unconstrained type and subtype expansion
1223 -- is disabled. To avoid back-end problems with shared profiles,
1224 -- use previous subprogram type as the designated type, and then
1225 -- remove scope added above.
1227 if ASIS_Mode and then Present (Scope (Defining_Identifier (F)))
1229 Set_Etype (T_Name, T_Name);
1230 Init_Size_Align (T_Name);
1231 Set_Directly_Designated_Type (T_Name,
1232 Scope (Defining_Identifier (F)));
1237 while Present (F) loop
1238 if No (Parent (Defining_Identifier (F))) then
1239 Set_Parent (Defining_Identifier (F), F);
1246 Process_Formals (Formals, Parent (T_Def));
1248 -- Special test 2) End_Scope requires that the parent pointer be set
1249 -- to something reasonable, but Itypes don't have parent pointers. So
1250 -- we set it and then unset it ???
1252 Set_Parent (Desig_Type, T_Name);
1254 Set_Parent (Desig_Type, Empty);
1257 -- Check for premature usage of the type being defined
1259 Check_For_Premature_Usage (T_Def);
1261 -- The return type and/or any parameter type may be incomplete. Mark the
1262 -- subprogram_type as depending on the incomplete type, so that it can
1263 -- be updated when the full type declaration is seen. This only applies
1264 -- to incomplete types declared in some enclosing scope, not to limited
1265 -- views from other packages.
1267 -- Prior to Ada 2012, access to functions can only have in_parameters.
1269 if Present (Formals) then
1270 Formal := First_Formal (Desig_Type);
1271 while Present (Formal) loop
1272 if Ekind (Formal) /= E_In_Parameter
1273 and then Nkind (T_Def) = N_Access_Function_Definition
1274 and then Ada_Version < Ada_2012
1276 Error_Msg_N ("functions can only have IN parameters", Formal);
1279 if Ekind (Etype (Formal)) = E_Incomplete_Type
1280 and then In_Open_Scopes (Scope (Etype (Formal)))
1282 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1283 Set_Has_Delayed_Freeze (Desig_Type);
1286 Next_Formal (Formal);
1290 -- Check whether an indirect call without actuals may be possible. This
1291 -- is used when resolving calls whose result is then indexed.
1293 May_Need_Actuals (Desig_Type);
1295 -- If the return type is incomplete, this is legal as long as the type
1296 -- is declared in the current scope and will be completed in it (rather
1297 -- than being part of limited view).
1299 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1300 and then not Has_Delayed_Freeze (Desig_Type)
1301 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1303 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1304 Set_Has_Delayed_Freeze (Desig_Type);
1307 Check_Delayed_Subprogram (Desig_Type);
1309 if Protected_Present (T_Def) then
1310 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1311 Set_Convention (Desig_Type, Convention_Protected);
1313 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1316 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1318 Set_Etype (T_Name, T_Name);
1319 Init_Size_Align (T_Name);
1320 Set_Directly_Designated_Type (T_Name, Desig_Type);
1322 Generate_Reference_To_Formals (T_Name);
1324 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1326 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1328 Check_Restriction (No_Access_Subprograms, T_Def);
1329 end Access_Subprogram_Declaration;
1331 ----------------------------
1332 -- Access_Type_Declaration --
1333 ----------------------------
1335 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1336 P : constant Node_Id := Parent (Def);
1337 S : constant Node_Id := Subtype_Indication (Def);
1339 Full_Desig : Entity_Id;
1342 Check_SPARK_05_Restriction ("access type is not allowed", Def);
1344 -- Check for permissible use of incomplete type
1346 if Nkind (S) /= N_Subtype_Indication then
1349 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1350 Set_Directly_Designated_Type (T, Entity (S));
1352 -- If the designated type is a limited view, we cannot tell if
1353 -- the full view contains tasks, and there is no way to handle
1354 -- that full view in a client. We create a master entity for the
1355 -- scope, which will be used when a client determines that one
1358 if From_Limited_With (Entity (S))
1359 and then not Is_Class_Wide_Type (Entity (S))
1361 Set_Ekind (T, E_Access_Type);
1362 Build_Master_Entity (T);
1363 Build_Master_Renaming (T);
1367 Set_Directly_Designated_Type (T, Process_Subtype (S, P, T, 'P'));
1370 -- If the access definition is of the form: ACCESS NOT NULL ..
1371 -- the subtype indication must be of an access type. Create
1372 -- a null-excluding subtype of it.
1374 if Null_Excluding_Subtype (Def) then
1375 if not Is_Access_Type (Entity (S)) then
1376 Error_Msg_N ("null exclusion must apply to access type", Def);
1380 Loc : constant Source_Ptr := Sloc (S);
1382 Nam : constant Entity_Id := Make_Temporary (Loc, 'S');
1386 Make_Subtype_Declaration (Loc,
1387 Defining_Identifier => Nam,
1388 Subtype_Indication =>
1389 New_Occurrence_Of (Entity (S), Loc));
1390 Set_Null_Exclusion_Present (Decl);
1391 Insert_Before (Parent (Def), Decl);
1393 Set_Entity (S, Nam);
1399 Set_Directly_Designated_Type (T,
1400 Process_Subtype (S, P, T, 'P'));
1403 if All_Present (Def) or Constant_Present (Def) then
1404 Set_Ekind (T, E_General_Access_Type);
1406 Set_Ekind (T, E_Access_Type);
1409 Full_Desig := Designated_Type (T);
1411 if Base_Type (Full_Desig) = T then
1412 Error_Msg_N ("access type cannot designate itself", S);
1414 -- In Ada 2005, the type may have a limited view through some unit in
1415 -- its own context, allowing the following circularity that cannot be
1416 -- detected earlier.
1418 elsif Is_Class_Wide_Type (Full_Desig) and then Etype (Full_Desig) = T
1421 ("access type cannot designate its own classwide type", S);
1423 -- Clean up indication of tagged status to prevent cascaded errors
1425 Set_Is_Tagged_Type (T, False);
1430 -- If the type has appeared already in a with_type clause, it is frozen
1431 -- and the pointer size is already set. Else, initialize.
1433 if not From_Limited_With (T) then
1434 Init_Size_Align (T);
1437 -- Note that Has_Task is always false, since the access type itself
1438 -- is not a task type. See Einfo for more description on this point.
1439 -- Exactly the same consideration applies to Has_Controlled_Component
1440 -- and to Has_Protected.
1442 Set_Has_Task (T, False);
1443 Set_Has_Controlled_Component (T, False);
1444 Set_Has_Protected (T, False);
1446 -- Initialize field Finalization_Master explicitly to Empty, to avoid
1447 -- problems where an incomplete view of this entity has been previously
1448 -- established by a limited with and an overlaid version of this field
1449 -- (Stored_Constraint) was initialized for the incomplete view.
1451 -- This reset is performed in most cases except where the access type
1452 -- has been created for the purposes of allocating or deallocating a
1453 -- build-in-place object. Such access types have explicitly set pools
1454 -- and finalization masters.
1456 if No (Associated_Storage_Pool (T)) then
1457 Set_Finalization_Master (T, Empty);
1460 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1463 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1464 Set_Is_Access_Constant (T, Constant_Present (Def));
1465 end Access_Type_Declaration;
1467 ----------------------------------
1468 -- Add_Interface_Tag_Components --
1469 ----------------------------------
1471 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1472 Loc : constant Source_Ptr := Sloc (N);
1476 procedure Add_Tag (Iface : Entity_Id);
1477 -- Add tag for one of the progenitor interfaces
1483 procedure Add_Tag (Iface : Entity_Id) is
1490 pragma Assert (Is_Tagged_Type (Iface) and then Is_Interface (Iface));
1492 -- This is a reasonable place to propagate predicates
1494 if Has_Predicates (Iface) then
1495 Set_Has_Predicates (Typ);
1499 Make_Component_Definition (Loc,
1500 Aliased_Present => True,
1501 Subtype_Indication =>
1502 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1504 Tag := Make_Temporary (Loc, 'V');
1507 Make_Component_Declaration (Loc,
1508 Defining_Identifier => Tag,
1509 Component_Definition => Def);
1511 Analyze_Component_Declaration (Decl);
1513 Set_Analyzed (Decl);
1514 Set_Ekind (Tag, E_Component);
1516 Set_Is_Aliased (Tag);
1517 Set_Related_Type (Tag, Iface);
1518 Init_Component_Location (Tag);
1520 pragma Assert (Is_Frozen (Iface));
1522 Set_DT_Entry_Count (Tag,
1523 DT_Entry_Count (First_Entity (Iface)));
1525 if No (Last_Tag) then
1528 Insert_After (Last_Tag, Decl);
1533 -- If the ancestor has discriminants we need to give special support
1534 -- to store the offset_to_top value of the secondary dispatch tables.
1535 -- For this purpose we add a supplementary component just after the
1536 -- field that contains the tag associated with each secondary DT.
1538 if Typ /= Etype (Typ) and then Has_Discriminants (Etype (Typ)) then
1540 Make_Component_Definition (Loc,
1541 Subtype_Indication =>
1542 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1544 Offset := Make_Temporary (Loc, 'V');
1547 Make_Component_Declaration (Loc,
1548 Defining_Identifier => Offset,
1549 Component_Definition => Def);
1551 Analyze_Component_Declaration (Decl);
1553 Set_Analyzed (Decl);
1554 Set_Ekind (Offset, E_Component);
1555 Set_Is_Aliased (Offset);
1556 Set_Related_Type (Offset, Iface);
1557 Init_Component_Location (Offset);
1558 Insert_After (Last_Tag, Decl);
1569 -- Start of processing for Add_Interface_Tag_Components
1572 if not RTE_Available (RE_Interface_Tag) then
1574 ("(Ada 2005) interface types not supported by this run-time!",
1579 if Ekind (Typ) /= E_Record_Type
1580 or else (Is_Concurrent_Record_Type (Typ)
1581 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1582 or else (not Is_Concurrent_Record_Type (Typ)
1583 and then No (Interfaces (Typ))
1584 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1589 -- Find the current last tag
1591 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1592 Ext := Record_Extension_Part (Type_Definition (N));
1594 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1595 Ext := Type_Definition (N);
1600 if not (Present (Component_List (Ext))) then
1601 Set_Null_Present (Ext, False);
1603 Set_Component_List (Ext,
1604 Make_Component_List (Loc,
1605 Component_Items => L,
1606 Null_Present => False));
1608 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1609 L := Component_Items
1611 (Record_Extension_Part
1612 (Type_Definition (N))));
1614 L := Component_Items
1616 (Type_Definition (N)));
1619 -- Find the last tag component
1622 while Present (Comp) loop
1623 if Nkind (Comp) = N_Component_Declaration
1624 and then Is_Tag (Defining_Identifier (Comp))
1633 -- At this point L references the list of components and Last_Tag
1634 -- references the current last tag (if any). Now we add the tag
1635 -- corresponding with all the interfaces that are not implemented
1638 if Present (Interfaces (Typ)) then
1639 Elmt := First_Elmt (Interfaces (Typ));
1640 while Present (Elmt) loop
1641 Add_Tag (Node (Elmt));
1645 end Add_Interface_Tag_Components;
1647 -------------------------------------
1648 -- Add_Internal_Interface_Entities --
1649 -------------------------------------
1651 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1654 Iface_Elmt : Elmt_Id;
1655 Iface_Prim : Entity_Id;
1656 Ifaces_List : Elist_Id;
1657 New_Subp : Entity_Id := Empty;
1659 Restore_Scope : Boolean := False;
1662 pragma Assert (Ada_Version >= Ada_2005
1663 and then Is_Record_Type (Tagged_Type)
1664 and then Is_Tagged_Type (Tagged_Type)
1665 and then Has_Interfaces (Tagged_Type)
1666 and then not Is_Interface (Tagged_Type));
1668 -- Ensure that the internal entities are added to the scope of the type
1670 if Scope (Tagged_Type) /= Current_Scope then
1671 Push_Scope (Scope (Tagged_Type));
1672 Restore_Scope := True;
1675 Collect_Interfaces (Tagged_Type, Ifaces_List);
1677 Iface_Elmt := First_Elmt (Ifaces_List);
1678 while Present (Iface_Elmt) loop
1679 Iface := Node (Iface_Elmt);
1681 -- Originally we excluded here from this processing interfaces that
1682 -- are parents of Tagged_Type because their primitives are located
1683 -- in the primary dispatch table (and hence no auxiliary internal
1684 -- entities are required to handle secondary dispatch tables in such
1685 -- case). However, these auxiliary entities are also required to
1686 -- handle derivations of interfaces in formals of generics (see
1687 -- Derive_Subprograms).
1689 Elmt := First_Elmt (Primitive_Operations (Iface));
1690 while Present (Elmt) loop
1691 Iface_Prim := Node (Elmt);
1693 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1695 Find_Primitive_Covering_Interface
1696 (Tagged_Type => Tagged_Type,
1697 Iface_Prim => Iface_Prim);
1699 if No (Prim) and then Serious_Errors_Detected > 0 then
1703 pragma Assert (Present (Prim));
1705 -- Ada 2012 (AI05-0197): If the name of the covering primitive
1706 -- differs from the name of the interface primitive then it is
1707 -- a private primitive inherited from a parent type. In such
1708 -- case, given that Tagged_Type covers the interface, the
1709 -- inherited private primitive becomes visible. For such
1710 -- purpose we add a new entity that renames the inherited
1711 -- private primitive.
1713 if Chars (Prim) /= Chars (Iface_Prim) then
1714 pragma Assert (Has_Suffix (Prim, 'P'));
1716 (New_Subp => New_Subp,
1717 Parent_Subp => Iface_Prim,
1718 Derived_Type => Tagged_Type,
1719 Parent_Type => Iface);
1720 Set_Alias (New_Subp, Prim);
1721 Set_Is_Abstract_Subprogram
1722 (New_Subp, Is_Abstract_Subprogram (Prim));
1726 (New_Subp => New_Subp,
1727 Parent_Subp => Iface_Prim,
1728 Derived_Type => Tagged_Type,
1729 Parent_Type => Iface);
1731 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1732 -- associated with interface types. These entities are
1733 -- only registered in the list of primitives of its
1734 -- corresponding tagged type because they are only used
1735 -- to fill the contents of the secondary dispatch tables.
1736 -- Therefore they are removed from the homonym chains.
1738 Set_Is_Hidden (New_Subp);
1739 Set_Is_Internal (New_Subp);
1740 Set_Alias (New_Subp, Prim);
1741 Set_Is_Abstract_Subprogram
1742 (New_Subp, Is_Abstract_Subprogram (Prim));
1743 Set_Interface_Alias (New_Subp, Iface_Prim);
1745 -- If the returned type is an interface then propagate it to
1746 -- the returned type. Needed by the thunk to generate the code
1747 -- which displaces "this" to reference the corresponding
1748 -- secondary dispatch table in the returned object.
1750 if Is_Interface (Etype (Iface_Prim)) then
1751 Set_Etype (New_Subp, Etype (Iface_Prim));
1754 -- Internal entities associated with interface types are
1755 -- only registered in the list of primitives of the tagged
1756 -- type. They are only used to fill the contents of the
1757 -- secondary dispatch tables. Therefore they are not needed
1758 -- in the homonym chains.
1760 Remove_Homonym (New_Subp);
1762 -- Hidden entities associated with interfaces must have set
1763 -- the Has_Delay_Freeze attribute to ensure that, in case of
1764 -- locally defined tagged types (or compiling with static
1765 -- dispatch tables generation disabled) the corresponding
1766 -- entry of the secondary dispatch table is filled when
1767 -- such an entity is frozen.
1769 Set_Has_Delayed_Freeze (New_Subp);
1776 Next_Elmt (Iface_Elmt);
1779 if Restore_Scope then
1782 end Add_Internal_Interface_Entities;
1784 -----------------------------------
1785 -- Analyze_Component_Declaration --
1786 -----------------------------------
1788 procedure Analyze_Component_Declaration (N : Node_Id) is
1789 Id : constant Entity_Id := Defining_Identifier (N);
1790 E : constant Node_Id := Expression (N);
1791 Typ : constant Node_Id :=
1792 Subtype_Indication (Component_Definition (N));
1796 function Contains_POC (Constr : Node_Id) return Boolean;
1797 -- Determines whether a constraint uses the discriminant of a record
1798 -- type thus becoming a per-object constraint (POC).
1800 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1801 -- Typ is the type of the current component, check whether this type is
1802 -- a limited type. Used to validate declaration against that of
1803 -- enclosing record.
1809 function Contains_POC (Constr : Node_Id) return Boolean is
1811 -- Prevent cascaded errors
1813 if Error_Posted (Constr) then
1817 case Nkind (Constr) is
1818 when N_Attribute_Reference =>
1819 return Attribute_Name (Constr) = Name_Access
1820 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1822 when N_Discriminant_Association =>
1823 return Denotes_Discriminant (Expression (Constr));
1825 when N_Identifier =>
1826 return Denotes_Discriminant (Constr);
1828 when N_Index_Or_Discriminant_Constraint =>
1833 IDC := First (Constraints (Constr));
1834 while Present (IDC) loop
1836 -- One per-object constraint is sufficient
1838 if Contains_POC (IDC) then
1849 return Denotes_Discriminant (Low_Bound (Constr))
1851 Denotes_Discriminant (High_Bound (Constr));
1853 when N_Range_Constraint =>
1854 return Denotes_Discriminant (Range_Expression (Constr));
1862 ----------------------
1863 -- Is_Known_Limited --
1864 ----------------------
1866 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1867 P : constant Entity_Id := Etype (Typ);
1868 R : constant Entity_Id := Root_Type (Typ);
1871 if Is_Limited_Record (Typ) then
1874 -- If the root type is limited (and not a limited interface)
1875 -- so is the current type
1877 elsif Is_Limited_Record (R)
1878 and then (not Is_Interface (R) or else not Is_Limited_Interface (R))
1882 -- Else the type may have a limited interface progenitor, but a
1883 -- limited record parent.
1885 elsif R /= P and then Is_Limited_Record (P) then
1891 end Is_Known_Limited;
1893 -- Start of processing for Analyze_Component_Declaration
1896 Generate_Definition (Id);
1899 if Present (Typ) then
1900 T := Find_Type_Of_Object
1901 (Subtype_Indication (Component_Definition (N)), N);
1903 if not Nkind_In (Typ, N_Identifier, N_Expanded_Name) then
1904 Check_SPARK_05_Restriction ("subtype mark required", Typ);
1907 -- Ada 2005 (AI-230): Access Definition case
1910 pragma Assert (Present
1911 (Access_Definition (Component_Definition (N))));
1913 T := Access_Definition
1915 N => Access_Definition (Component_Definition (N)));
1916 Set_Is_Local_Anonymous_Access (T);
1918 -- Ada 2005 (AI-254)
1920 if Present (Access_To_Subprogram_Definition
1921 (Access_Definition (Component_Definition (N))))
1922 and then Protected_Present (Access_To_Subprogram_Definition
1924 (Component_Definition (N))))
1926 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1930 -- If the subtype is a constrained subtype of the enclosing record,
1931 -- (which must have a partial view) the back-end does not properly
1932 -- handle the recursion. Rewrite the component declaration with an
1933 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1934 -- the tree directly because side effects have already been removed from
1935 -- discriminant constraints.
1937 if Ekind (T) = E_Access_Subtype
1938 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1939 and then Comes_From_Source (T)
1940 and then Nkind (Parent (T)) = N_Subtype_Declaration
1941 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1944 (Subtype_Indication (Component_Definition (N)),
1945 New_Copy_Tree (Subtype_Indication (Parent (T))));
1946 T := Find_Type_Of_Object
1947 (Subtype_Indication (Component_Definition (N)), N);
1950 -- If the component declaration includes a default expression, then we
1951 -- check that the component is not of a limited type (RM 3.7(5)),
1952 -- and do the special preanalysis of the expression (see section on
1953 -- "Handling of Default and Per-Object Expressions" in the spec of
1957 Check_SPARK_05_Restriction ("default expression is not allowed", E);
1958 Preanalyze_Default_Expression (E, T);
1959 Check_Initialization (T, E);
1961 if Ada_Version >= Ada_2005
1962 and then Ekind (T) = E_Anonymous_Access_Type
1963 and then Etype (E) /= Any_Type
1965 -- Check RM 3.9.2(9): "if the expected type for an expression is
1966 -- an anonymous access-to-specific tagged type, then the object
1967 -- designated by the expression shall not be dynamically tagged
1968 -- unless it is a controlling operand in a call on a dispatching
1971 if Is_Tagged_Type (Directly_Designated_Type (T))
1973 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1975 Ekind (Directly_Designated_Type (Etype (E))) =
1979 ("access to specific tagged type required (RM 3.9.2(9))", E);
1982 -- (Ada 2005: AI-230): Accessibility check for anonymous
1985 if Type_Access_Level (Etype (E)) >
1986 Deepest_Type_Access_Level (T)
1989 ("expression has deeper access level than component " &
1990 "(RM 3.10.2 (12.2))", E);
1993 -- The initialization expression is a reference to an access
1994 -- discriminant. The type of the discriminant is always deeper
1995 -- than any access type.
1997 if Ekind (Etype (E)) = E_Anonymous_Access_Type
1998 and then Is_Entity_Name (E)
1999 and then Ekind (Entity (E)) = E_In_Parameter
2000 and then Present (Discriminal_Link (Entity (E)))
2003 ("discriminant has deeper accessibility level than target",
2009 -- The parent type may be a private view with unknown discriminants,
2010 -- and thus unconstrained. Regular components must be constrained.
2012 if Is_Indefinite_Subtype (T) and then Chars (Id) /= Name_uParent then
2013 if Is_Class_Wide_Type (T) then
2015 ("class-wide subtype with unknown discriminants" &
2016 " in component declaration",
2017 Subtype_Indication (Component_Definition (N)));
2020 ("unconstrained subtype in component declaration",
2021 Subtype_Indication (Component_Definition (N)));
2024 -- Components cannot be abstract, except for the special case of
2025 -- the _Parent field (case of extending an abstract tagged type)
2027 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
2028 Error_Msg_N ("type of a component cannot be abstract", N);
2032 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
2034 -- The component declaration may have a per-object constraint, set
2035 -- the appropriate flag in the defining identifier of the subtype.
2037 if Present (Subtype_Indication (Component_Definition (N))) then
2039 Sindic : constant Node_Id :=
2040 Subtype_Indication (Component_Definition (N));
2042 if Nkind (Sindic) = N_Subtype_Indication
2043 and then Present (Constraint (Sindic))
2044 and then Contains_POC (Constraint (Sindic))
2046 Set_Has_Per_Object_Constraint (Id);
2051 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2052 -- out some static checks.
2054 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
2055 Null_Exclusion_Static_Checks (N);
2058 -- If this component is private (or depends on a private type), flag the
2059 -- record type to indicate that some operations are not available.
2061 P := Private_Component (T);
2065 -- Check for circular definitions
2067 if P = Any_Type then
2068 Set_Etype (Id, Any_Type);
2070 -- There is a gap in the visibility of operations only if the
2071 -- component type is not defined in the scope of the record type.
2073 elsif Scope (P) = Scope (Current_Scope) then
2076 elsif Is_Limited_Type (P) then
2077 Set_Is_Limited_Composite (Current_Scope);
2080 Set_Is_Private_Composite (Current_Scope);
2085 and then Is_Limited_Type (T)
2086 and then Chars (Id) /= Name_uParent
2087 and then Is_Tagged_Type (Current_Scope)
2089 if Is_Derived_Type (Current_Scope)
2090 and then not Is_Known_Limited (Current_Scope)
2093 ("extension of nonlimited type cannot have limited components",
2096 if Is_Interface (Root_Type (Current_Scope)) then
2098 ("\limitedness is not inherited from limited interface", N);
2099 Error_Msg_N ("\add LIMITED to type indication", N);
2102 Explain_Limited_Type (T, N);
2103 Set_Etype (Id, Any_Type);
2104 Set_Is_Limited_Composite (Current_Scope, False);
2106 elsif not Is_Derived_Type (Current_Scope)
2107 and then not Is_Limited_Record (Current_Scope)
2108 and then not Is_Concurrent_Type (Current_Scope)
2111 ("nonlimited tagged type cannot have limited components", N);
2112 Explain_Limited_Type (T, N);
2113 Set_Etype (Id, Any_Type);
2114 Set_Is_Limited_Composite (Current_Scope, False);
2118 Set_Original_Record_Component (Id, Id);
2120 if Has_Aspects (N) then
2121 Analyze_Aspect_Specifications (N, Id);
2124 Analyze_Dimension (N);
2125 end Analyze_Component_Declaration;
2127 --------------------------
2128 -- Analyze_Declarations --
2129 --------------------------
2131 procedure Analyze_Declarations (L : List_Id) is
2134 procedure Adjust_Decl;
2135 -- Adjust Decl not to include implicit label declarations, since these
2136 -- have strange Sloc values that result in elaboration check problems.
2137 -- (They have the sloc of the label as found in the source, and that
2138 -- is ahead of the current declarative part).
2140 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id);
2141 -- Determine whether Body_Decl denotes the body of a late controlled
2142 -- primitive (either Initialize, Adjust or Finalize). If this is the
2143 -- case, add a proper spec if the body lacks one. The spec is inserted
2144 -- before Body_Decl and immedately analyzed.
2146 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id);
2147 -- Spec_Id is the entity of a package that may define abstract states.
2148 -- If the states have visible refinement, remove the visibility of each
2149 -- constituent at the end of the package body declarations.
2155 procedure Adjust_Decl is
2157 while Present (Prev (Decl))
2158 and then Nkind (Decl) = N_Implicit_Label_Declaration
2164 --------------------------------------
2165 -- Handle_Late_Controlled_Primitive --
2166 --------------------------------------
2168 procedure Handle_Late_Controlled_Primitive (Body_Decl : Node_Id) is
2169 Body_Spec : constant Node_Id := Specification (Body_Decl);
2170 Body_Id : constant Entity_Id := Defining_Entity (Body_Spec);
2171 Loc : constant Source_Ptr := Sloc (Body_Id);
2172 Params : constant List_Id :=
2173 Parameter_Specifications (Body_Spec);
2175 Spec_Id : Entity_Id;
2179 -- Consider only procedure bodies whose name matches one of the three
2180 -- controlled primitives.
2182 if Nkind (Body_Spec) /= N_Procedure_Specification
2183 or else not Nam_In (Chars (Body_Id), Name_Adjust,
2189 -- A controlled primitive must have exactly one formal which is not
2190 -- an anonymous access type.
2192 elsif List_Length (Params) /= 1 then
2196 Typ := Parameter_Type (First (Params));
2198 if Nkind (Typ) = N_Access_Definition then
2204 -- The type of the formal must be derived from [Limited_]Controlled
2206 if not Is_Controlled (Entity (Typ)) then
2210 -- Check whether a specification exists for this body. We do not
2211 -- analyze the spec of the body in full, because it will be analyzed
2212 -- again when the body is properly analyzed, and we cannot create
2213 -- duplicate entries in the formals chain. We look for an explicit
2214 -- specification because the body may be an overriding operation and
2215 -- an inherited spec may be present.
2217 Spec_Id := Current_Entity (Body_Id);
2219 while Present (Spec_Id) loop
2220 if Ekind_In (Spec_Id, E_Procedure, E_Generic_Procedure)
2221 and then Scope (Spec_Id) = Current_Scope
2222 and then Present (First_Formal (Spec_Id))
2223 and then No (Next_Formal (First_Formal (Spec_Id)))
2224 and then Etype (First_Formal (Spec_Id)) = Entity (Typ)
2225 and then Comes_From_Source (Spec_Id)
2230 Spec_Id := Homonym (Spec_Id);
2233 -- At this point the body is known to be a late controlled primitive.
2234 -- Generate a matching spec and insert it before the body. Note the
2235 -- use of Copy_Separate_Tree - we want an entirely separate semantic
2236 -- tree in this case.
2238 Spec := Copy_Separate_Tree (Body_Spec);
2240 -- Ensure that the subprogram declaration does not inherit the null
2241 -- indicator from the body as we now have a proper spec/body pair.
2243 Set_Null_Present (Spec, False);
2245 Insert_Before_And_Analyze (Body_Decl,
2246 Make_Subprogram_Declaration (Loc, Specification => Spec));
2247 end Handle_Late_Controlled_Primitive;
2249 --------------------------------
2250 -- Remove_Visible_Refinements --
2251 --------------------------------
2253 procedure Remove_Visible_Refinements (Spec_Id : Entity_Id) is
2254 State_Elmt : Elmt_Id;
2256 if Present (Abstract_States (Spec_Id)) then
2257 State_Elmt := First_Elmt (Abstract_States (Spec_Id));
2258 while Present (State_Elmt) loop
2259 Set_Has_Visible_Refinement (Node (State_Elmt), False);
2260 Next_Elmt (State_Elmt);
2263 end Remove_Visible_Refinements;
2268 Freeze_From : Entity_Id := Empty;
2269 Next_Decl : Node_Id;
2270 Spec_Id : Entity_Id;
2272 Body_Seen : Boolean := False;
2273 -- Flag set when the first body [stub] is encountered
2275 In_Package_Body : Boolean := False;
2276 -- Flag set when the current declaration list belongs to a package body
2278 -- Start of processing for Analyze_Declarations
2281 if Restriction_Check_Required (SPARK_05) then
2282 Check_Later_Vs_Basic_Declarations (L, During_Parsing => False);
2286 while Present (Decl) loop
2288 -- Package spec cannot contain a package declaration in SPARK
2290 if Nkind (Decl) = N_Package_Declaration
2291 and then Nkind (Parent (L)) = N_Package_Specification
2293 Check_SPARK_05_Restriction
2294 ("package specification cannot contain a package declaration",
2298 -- Complete analysis of declaration
2301 Next_Decl := Next (Decl);
2303 if No (Freeze_From) then
2304 Freeze_From := First_Entity (Current_Scope);
2307 -- At the end of a declarative part, freeze remaining entities
2308 -- declared in it. The end of the visible declarations of package
2309 -- specification is not the end of a declarative part if private
2310 -- declarations are present. The end of a package declaration is a
2311 -- freezing point only if it a library package. A task definition or
2312 -- protected type definition is not a freeze point either. Finally,
2313 -- we do not freeze entities in generic scopes, because there is no
2314 -- code generated for them and freeze nodes will be generated for
2317 -- The end of a package instantiation is not a freeze point, but
2318 -- for now we make it one, because the generic body is inserted
2319 -- (currently) immediately after. Generic instantiations will not
2320 -- be a freeze point once delayed freezing of bodies is implemented.
2321 -- (This is needed in any case for early instantiations ???).
2323 if No (Next_Decl) then
2324 if Nkind_In (Parent (L), N_Component_List,
2326 N_Protected_Definition)
2330 elsif Nkind (Parent (L)) /= N_Package_Specification then
2331 if Nkind (Parent (L)) = N_Package_Body then
2332 Freeze_From := First_Entity (Current_Scope);
2335 -- There may have been several freezing points previously,
2336 -- for example object declarations or subprogram bodies, but
2337 -- at the end of a declarative part we check freezing from
2338 -- the beginning, even though entities may already be frozen,
2339 -- in order to perform visibility checks on delayed aspects.
2342 Freeze_All (First_Entity (Current_Scope), Decl);
2343 Freeze_From := Last_Entity (Current_Scope);
2345 elsif Scope (Current_Scope) /= Standard_Standard
2346 and then not Is_Child_Unit (Current_Scope)
2347 and then No (Generic_Parent (Parent (L)))
2351 elsif L /= Visible_Declarations (Parent (L))
2352 or else No (Private_Declarations (Parent (L)))
2353 or else Is_Empty_List (Private_Declarations (Parent (L)))
2356 Freeze_All (First_Entity (Current_Scope), Decl);
2357 Freeze_From := Last_Entity (Current_Scope);
2360 -- If next node is a body then freeze all types before the body.
2361 -- An exception occurs for some expander-generated bodies. If these
2362 -- are generated at places where in general language rules would not
2363 -- allow a freeze point, then we assume that the expander has
2364 -- explicitly checked that all required types are properly frozen,
2365 -- and we do not cause general freezing here. This special circuit
2366 -- is used when the encountered body is marked as having already
2369 -- In all other cases (bodies that come from source, and expander
2370 -- generated bodies that have not been analyzed yet), freeze all
2371 -- types now. Note that in the latter case, the expander must take
2372 -- care to attach the bodies at a proper place in the tree so as to
2373 -- not cause unwanted freezing at that point.
2375 elsif not Analyzed (Next_Decl) and then Is_Body (Next_Decl) then
2377 -- When a controlled type is frozen, the expander generates stream
2378 -- and controlled type support routines. If the freeze is caused
2379 -- by the stand alone body of Initialize, Adjust and Finalize, the
2380 -- expander will end up using the wrong version of these routines
2381 -- as the body has not been processed yet. To remedy this, detect
2382 -- a late controlled primitive and create a proper spec for it.
2383 -- This ensures that the primitive will override its inherited
2384 -- counterpart before the freeze takes place.
2386 -- If the declaration we just processed is a body, do not attempt
2387 -- to examine Next_Decl as the late primitive idiom can only apply
2388 -- to the first encountered body.
2390 -- The spec of the late primitive is not generated in ASIS mode to
2391 -- ensure a consistent list of primitives that indicates the true
2392 -- semantic structure of the program (which is not relevant when
2393 -- generating executable code.
2395 -- ??? a cleaner approach may be possible and/or this solution
2396 -- could be extended to general-purpose late primitives, TBD.
2398 if not ASIS_Mode and then not Body_Seen and then not Is_Body (Decl)
2402 if Nkind (Next_Decl) = N_Subprogram_Body then
2403 Handle_Late_Controlled_Primitive (Next_Decl);
2408 Freeze_All (Freeze_From, Decl);
2409 Freeze_From := Last_Entity (Current_Scope);
2415 -- Analyze the contracts of packages and their bodies
2418 Context := Parent (L);
2420 if Nkind (Context) = N_Package_Specification then
2422 -- When a package has private declarations, its contract must be
2423 -- analyzed at the end of the said declarations. This way both the
2424 -- analysis and freeze actions are properly synchronized in case
2425 -- of private type use within the contract.
2427 if L = Private_Declarations (Context) then
2428 Analyze_Package_Contract (Defining_Entity (Context));
2430 -- Build the bodies of the default initial condition procedures
2431 -- for all types subject to pragma Default_Initial_Condition.
2432 -- From a purely Ada stand point, this is a freezing activity,
2433 -- however freezing is not available under GNATprove_Mode. To
2434 -- accomodate both scenarios, the bodies are build at the end
2435 -- of private declaration analysis.
2437 Build_Default_Init_Cond_Procedure_Bodies (L);
2439 -- Otherwise the contract is analyzed at the end of the visible
2442 elsif L = Visible_Declarations (Context)
2443 and then No (Private_Declarations (Context))
2445 Analyze_Package_Contract (Defining_Entity (Context));
2448 elsif Nkind (Context) = N_Package_Body then
2449 In_Package_Body := True;
2450 Spec_Id := Corresponding_Spec (Context);
2452 Analyze_Package_Body_Contract (Defining_Entity (Context));
2456 -- Analyze the contracts of subprogram declarations, subprogram bodies
2457 -- and variables now due to the delayed visibility requirements of their
2461 while Present (Decl) loop
2462 if Nkind (Decl) = N_Object_Declaration then
2463 Analyze_Object_Contract (Defining_Entity (Decl));
2465 elsif Nkind_In (Decl, N_Abstract_Subprogram_Declaration,
2466 N_Subprogram_Declaration)
2468 Analyze_Subprogram_Contract (Defining_Entity (Decl));
2470 elsif Nkind (Decl) = N_Subprogram_Body then
2471 Analyze_Subprogram_Body_Contract (Defining_Entity (Decl));
2473 elsif Nkind (Decl) = N_Subprogram_Body_Stub then
2474 Analyze_Subprogram_Body_Stub_Contract (Defining_Entity (Decl));
2480 -- State refinements are visible upto the end the of the package body
2481 -- declarations. Hide the refinements from visibility to restore the
2482 -- original state conditions.
2484 if In_Package_Body then
2485 Remove_Visible_Refinements (Spec_Id);
2487 end Analyze_Declarations;
2489 -----------------------------------
2490 -- Analyze_Full_Type_Declaration --
2491 -----------------------------------
2493 procedure Analyze_Full_Type_Declaration (N : Node_Id) is
2494 Def : constant Node_Id := Type_Definition (N);
2495 Def_Id : constant Entity_Id := Defining_Identifier (N);
2499 Is_Remote : constant Boolean :=
2500 (Is_Remote_Types (Current_Scope)
2501 or else Is_Remote_Call_Interface (Current_Scope))
2502 and then not (In_Private_Part (Current_Scope)
2503 or else In_Package_Body (Current_Scope));
2505 procedure Check_Ops_From_Incomplete_Type;
2506 -- If there is a tagged incomplete partial view of the type, traverse
2507 -- the primitives of the incomplete view and change the type of any
2508 -- controlling formals and result to indicate the full view. The
2509 -- primitives will be added to the full type's primitive operations
2510 -- list later in Sem_Disp.Check_Operation_From_Incomplete_Type (which
2511 -- is called from Process_Incomplete_Dependents).
2513 ------------------------------------
2514 -- Check_Ops_From_Incomplete_Type --
2515 ------------------------------------
2517 procedure Check_Ops_From_Incomplete_Type is
2524 and then Ekind (Prev) = E_Incomplete_Type
2525 and then Is_Tagged_Type (Prev)
2526 and then Is_Tagged_Type (T)
2528 Elmt := First_Elmt (Primitive_Operations (Prev));
2529 while Present (Elmt) loop
2532 Formal := First_Formal (Op);
2533 while Present (Formal) loop
2534 if Etype (Formal) = Prev then
2535 Set_Etype (Formal, T);
2538 Next_Formal (Formal);
2541 if Etype (Op) = Prev then
2548 end Check_Ops_From_Incomplete_Type;
2550 -- Start of processing for Analyze_Full_Type_Declaration
2553 Prev := Find_Type_Name (N);
2555 -- The full view, if present, now points to the current type
2556 -- If there is an incomplete partial view, set a link to it, to
2557 -- simplify the retrieval of primitive operations of the type.
2559 -- Ada 2005 (AI-50217): If the type was previously decorated when
2560 -- imported through a LIMITED WITH clause, it appears as incomplete
2561 -- but has no full view.
2563 if Ekind (Prev) = E_Incomplete_Type
2564 and then Present (Full_View (Prev))
2566 T := Full_View (Prev);
2567 Set_Incomplete_View (N, Parent (Prev));
2572 Set_Is_Pure (T, Is_Pure (Current_Scope));
2574 -- We set the flag Is_First_Subtype here. It is needed to set the
2575 -- corresponding flag for the Implicit class-wide-type created
2576 -- during tagged types processing.
2578 Set_Is_First_Subtype (T, True);
2580 -- Only composite types other than array types are allowed to have
2585 -- For derived types, the rule will be checked once we've figured
2586 -- out the parent type.
2588 when N_Derived_Type_Definition =>
2591 -- For record types, discriminants are allowed, unless we are in
2594 when N_Record_Definition =>
2595 if Present (Discriminant_Specifications (N)) then
2596 Check_SPARK_05_Restriction
2597 ("discriminant type is not allowed",
2599 (First (Discriminant_Specifications (N))));
2603 if Present (Discriminant_Specifications (N)) then
2605 ("elementary or array type cannot have discriminants",
2607 (First (Discriminant_Specifications (N))));
2611 -- Elaborate the type definition according to kind, and generate
2612 -- subsidiary (implicit) subtypes where needed. We skip this if it was
2613 -- already done (this happens during the reanalysis that follows a call
2614 -- to the high level optimizer).
2616 if not Analyzed (T) then
2620 when N_Access_To_Subprogram_Definition =>
2621 Access_Subprogram_Declaration (T, Def);
2623 -- If this is a remote access to subprogram, we must create the
2624 -- equivalent fat pointer type, and related subprograms.
2627 Process_Remote_AST_Declaration (N);
2630 -- Validate categorization rule against access type declaration
2631 -- usually a violation in Pure unit, Shared_Passive unit.
2633 Validate_Access_Type_Declaration (T, N);
2635 when N_Access_To_Object_Definition =>
2636 Access_Type_Declaration (T, Def);
2638 -- Validate categorization rule against access type declaration
2639 -- usually a violation in Pure unit, Shared_Passive unit.
2641 Validate_Access_Type_Declaration (T, N);
2643 -- If we are in a Remote_Call_Interface package and define a
2644 -- RACW, then calling stubs and specific stream attributes
2648 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
2650 Add_RACW_Features (Def_Id);
2653 -- Set no strict aliasing flag if config pragma seen
2655 if Opt.No_Strict_Aliasing then
2656 Set_No_Strict_Aliasing (Base_Type (Def_Id));
2659 when N_Array_Type_Definition =>
2660 Array_Type_Declaration (T, Def);
2662 when N_Derived_Type_Definition =>
2663 Derived_Type_Declaration (T, N, T /= Def_Id);
2665 when N_Enumeration_Type_Definition =>
2666 Enumeration_Type_Declaration (T, Def);
2668 when N_Floating_Point_Definition =>
2669 Floating_Point_Type_Declaration (T, Def);
2671 when N_Decimal_Fixed_Point_Definition =>
2672 Decimal_Fixed_Point_Type_Declaration (T, Def);
2674 when N_Ordinary_Fixed_Point_Definition =>
2675 Ordinary_Fixed_Point_Type_Declaration (T, Def);
2677 when N_Signed_Integer_Type_Definition =>
2678 Signed_Integer_Type_Declaration (T, Def);
2680 when N_Modular_Type_Definition =>
2681 Modular_Type_Declaration (T, Def);
2683 when N_Record_Definition =>
2684 Record_Type_Declaration (T, N, Prev);
2686 -- If declaration has a parse error, nothing to elaborate.
2692 raise Program_Error;
2697 if Etype (T) = Any_Type then
2701 -- Controlled type is not allowed in SPARK
2703 if Is_Visibly_Controlled (T) then
2704 Check_SPARK_05_Restriction ("controlled type is not allowed", N);
2707 -- A type declared within a Ghost scope is automatically Ghost
2708 -- (SPARK RM 6.9(2)).
2710 if Comes_From_Source (T) and then Within_Ghost_Scope then
2711 Set_Is_Ghost_Entity (T);
2714 -- Some common processing for all types
2716 Set_Depends_On_Private (T, Has_Private_Component (T));
2717 Check_Ops_From_Incomplete_Type;
2719 -- Both the declared entity, and its anonymous base type if one was
2720 -- created, need freeze nodes allocated.
2723 B : constant Entity_Id := Base_Type (T);
2726 -- In the case where the base type differs from the first subtype, we
2727 -- pre-allocate a freeze node, and set the proper link to the first
2728 -- subtype. Freeze_Entity will use this preallocated freeze node when
2729 -- it freezes the entity.
2731 -- This does not apply if the base type is a generic type, whose
2732 -- declaration is independent of the current derived definition.
2734 if B /= T and then not Is_Generic_Type (B) then
2735 Ensure_Freeze_Node (B);
2736 Set_First_Subtype_Link (Freeze_Node (B), T);
2739 -- A type that is imported through a limited_with clause cannot
2740 -- generate any code, and thus need not be frozen. However, an access
2741 -- type with an imported designated type needs a finalization list,
2742 -- which may be referenced in some other package that has non-limited
2743 -- visibility on the designated type. Thus we must create the
2744 -- finalization list at the point the access type is frozen, to
2745 -- prevent unsatisfied references at link time.
2747 if not From_Limited_With (T) or else Is_Access_Type (T) then
2748 Set_Has_Delayed_Freeze (T);
2752 -- Case where T is the full declaration of some private type which has
2753 -- been swapped in Defining_Identifier (N).
2755 if T /= Def_Id and then Is_Private_Type (Def_Id) then
2756 Process_Full_View (N, T, Def_Id);
2758 -- Record the reference. The form of this is a little strange, since
2759 -- the full declaration has been swapped in. So the first parameter
2760 -- here represents the entity to which a reference is made which is
2761 -- the "real" entity, i.e. the one swapped in, and the second
2762 -- parameter provides the reference location.
2764 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
2765 -- since we don't want a complaint about the full type being an
2766 -- unwanted reference to the private type
2769 B : constant Boolean := Has_Pragma_Unreferenced (T);
2771 Set_Has_Pragma_Unreferenced (T, False);
2772 Generate_Reference (T, T, 'c');
2773 Set_Has_Pragma_Unreferenced (T, B);
2776 Set_Completion_Referenced (Def_Id);
2778 -- For completion of incomplete type, process incomplete dependents
2779 -- and always mark the full type as referenced (it is the incomplete
2780 -- type that we get for any real reference).
2782 elsif Ekind (Prev) = E_Incomplete_Type then
2783 Process_Incomplete_Dependents (N, T, Prev);
2784 Generate_Reference (Prev, Def_Id, 'c');
2785 Set_Completion_Referenced (Def_Id);
2787 -- If not private type or incomplete type completion, this is a real
2788 -- definition of a new entity, so record it.
2791 Generate_Definition (Def_Id);
2794 if Chars (Scope (Def_Id)) = Name_System
2795 and then Chars (Def_Id) = Name_Address
2796 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
2798 Set_Is_Descendent_Of_Address (Def_Id);
2799 Set_Is_Descendent_Of_Address (Base_Type (Def_Id));
2800 Set_Is_Descendent_Of_Address (Prev);
2803 Set_Optimize_Alignment_Flags (Def_Id);
2804 Check_Eliminated (Def_Id);
2806 -- If the declaration is a completion and aspects are present, apply
2807 -- them to the entity for the type which is currently the partial
2808 -- view, but which is the one that will be frozen.
2810 if Has_Aspects (N) then
2812 -- In most cases the partial view is a private type, and both views
2813 -- appear in different declarative parts. In the unusual case where
2814 -- the partial view is incomplete, perform the analysis on the
2815 -- full view, to prevent freezing anomalies with the corresponding
2816 -- class-wide type, which otherwise might be frozen before the
2817 -- dispatch table is built.
2820 and then Ekind (Prev) /= E_Incomplete_Type
2822 Analyze_Aspect_Specifications (N, Prev);
2827 Analyze_Aspect_Specifications (N, Def_Id);
2830 end Analyze_Full_Type_Declaration;
2832 ----------------------------------
2833 -- Analyze_Incomplete_Type_Decl --
2834 ----------------------------------
2836 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
2837 F : constant Boolean := Is_Pure (Current_Scope);
2841 Check_SPARK_05_Restriction ("incomplete type is not allowed", N);
2843 Generate_Definition (Defining_Identifier (N));
2845 -- Process an incomplete declaration. The identifier must not have been
2846 -- declared already in the scope. However, an incomplete declaration may
2847 -- appear in the private part of a package, for a private type that has
2848 -- already been declared.
2850 -- In this case, the discriminants (if any) must match
2852 T := Find_Type_Name (N);
2854 Set_Ekind (T, E_Incomplete_Type);
2855 Init_Size_Align (T);
2856 Set_Is_First_Subtype (T, True);
2859 -- An incomplete type declared within a Ghost scope is automatically
2860 -- Ghost (SPARK RM 6.9(2)).
2862 if Within_Ghost_Scope then
2863 Set_Is_Ghost_Entity (T);
2866 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
2867 -- incomplete types.
2869 if Tagged_Present (N) then
2870 Set_Is_Tagged_Type (T, True);
2871 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
2872 Make_Class_Wide_Type (T);
2873 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2878 Set_Stored_Constraint (T, No_Elist);
2880 if Present (Discriminant_Specifications (N)) then
2881 Process_Discriminants (N);
2886 -- If the type has discriminants, non-trivial subtypes may be
2887 -- declared before the full view of the type. The full views of those
2888 -- subtypes will be built after the full view of the type.
2890 Set_Private_Dependents (T, New_Elmt_List);
2892 end Analyze_Incomplete_Type_Decl;
2894 -----------------------------------
2895 -- Analyze_Interface_Declaration --
2896 -----------------------------------
2898 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
2899 CW : constant Entity_Id := Class_Wide_Type (T);
2902 Set_Is_Tagged_Type (T);
2903 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
2905 Set_Is_Limited_Record (T, Limited_Present (Def)
2906 or else Task_Present (Def)
2907 or else Protected_Present (Def)
2908 or else Synchronized_Present (Def));
2910 -- Type is abstract if full declaration carries keyword, or if previous
2911 -- partial view did.
2913 Set_Is_Abstract_Type (T);
2914 Set_Is_Interface (T);
2916 -- Type is a limited interface if it includes the keyword limited, task,
2917 -- protected, or synchronized.
2919 Set_Is_Limited_Interface
2920 (T, Limited_Present (Def)
2921 or else Protected_Present (Def)
2922 or else Synchronized_Present (Def)
2923 or else Task_Present (Def));
2925 Set_Interfaces (T, New_Elmt_List);
2926 Set_Direct_Primitive_Operations (T, New_Elmt_List);
2928 -- Complete the decoration of the class-wide entity if it was already
2929 -- built (i.e. during the creation of the limited view)
2931 if Present (CW) then
2932 Set_Is_Interface (CW);
2933 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
2936 -- Check runtime support for synchronized interfaces
2938 if VM_Target = No_VM
2939 and then (Is_Task_Interface (T)
2940 or else Is_Protected_Interface (T)
2941 or else Is_Synchronized_Interface (T))
2942 and then not RTE_Available (RE_Select_Specific_Data)
2944 Error_Msg_CRT ("synchronized interfaces", T);
2946 end Analyze_Interface_Declaration;
2948 -----------------------------
2949 -- Analyze_Itype_Reference --
2950 -----------------------------
2952 -- Nothing to do. This node is placed in the tree only for the benefit of
2953 -- back end processing, and has no effect on the semantic processing.
2955 procedure Analyze_Itype_Reference (N : Node_Id) is
2957 pragma Assert (Is_Itype (Itype (N)));
2959 end Analyze_Itype_Reference;
2961 --------------------------------
2962 -- Analyze_Number_Declaration --
2963 --------------------------------
2965 procedure Analyze_Number_Declaration (N : Node_Id) is
2966 Id : constant Entity_Id := Defining_Identifier (N);
2967 E : constant Node_Id := Expression (N);
2969 Index : Interp_Index;
2973 Generate_Definition (Id);
2976 -- A number declared within a Ghost scope is automatically Ghost
2977 -- (SPARK RM 6.9(2)).
2979 if Within_Ghost_Scope then
2980 Set_Is_Ghost_Entity (Id);
2983 -- This is an optimization of a common case of an integer literal
2985 if Nkind (E) = N_Integer_Literal then
2986 Set_Is_Static_Expression (E, True);
2987 Set_Etype (E, Universal_Integer);
2989 Set_Etype (Id, Universal_Integer);
2990 Set_Ekind (Id, E_Named_Integer);
2991 Set_Is_Frozen (Id, True);
2995 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2997 -- Process expression, replacing error by integer zero, to avoid
2998 -- cascaded errors or aborts further along in the processing
3000 -- Replace Error by integer zero, which seems least likely to cause
3004 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
3005 Set_Error_Posted (E);
3010 -- Verify that the expression is static and numeric. If
3011 -- the expression is overloaded, we apply the preference
3012 -- rule that favors root numeric types.
3014 if not Is_Overloaded (E) then
3016 if Has_Dynamic_Predicate_Aspect (T) then
3018 ("subtype has dynamic predicate, "
3019 & "not allowed in number declaration", N);
3025 Get_First_Interp (E, Index, It);
3026 while Present (It.Typ) loop
3027 if (Is_Integer_Type (It.Typ) or else Is_Real_Type (It.Typ))
3028 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
3030 if T = Any_Type then
3033 elsif It.Typ = Universal_Real
3035 It.Typ = Universal_Integer
3037 -- Choose universal interpretation over any other
3044 Get_Next_Interp (Index, It);
3048 if Is_Integer_Type (T) then
3050 Set_Etype (Id, Universal_Integer);
3051 Set_Ekind (Id, E_Named_Integer);
3053 elsif Is_Real_Type (T) then
3055 -- Because the real value is converted to universal_real, this is a
3056 -- legal context for a universal fixed expression.
3058 if T = Universal_Fixed then
3060 Loc : constant Source_Ptr := Sloc (N);
3061 Conv : constant Node_Id := Make_Type_Conversion (Loc,
3063 New_Occurrence_Of (Universal_Real, Loc),
3064 Expression => Relocate_Node (E));
3071 elsif T = Any_Fixed then
3072 Error_Msg_N ("illegal context for mixed mode operation", E);
3074 -- Expression is of the form : universal_fixed * integer. Try to
3075 -- resolve as universal_real.
3077 T := Universal_Real;
3082 Set_Etype (Id, Universal_Real);
3083 Set_Ekind (Id, E_Named_Real);
3086 Wrong_Type (E, Any_Numeric);
3090 Set_Ekind (Id, E_Constant);
3091 Set_Never_Set_In_Source (Id, True);
3092 Set_Is_True_Constant (Id, True);
3096 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
3097 Set_Etype (E, Etype (Id));
3100 if not Is_OK_Static_Expression (E) then
3101 Flag_Non_Static_Expr
3102 ("non-static expression used in number declaration!", E);
3103 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
3104 Set_Etype (E, Any_Type);
3106 end Analyze_Number_Declaration;
3108 -----------------------------
3109 -- Analyze_Object_Contract --
3110 -----------------------------
3112 procedure Analyze_Object_Contract (Obj_Id : Entity_Id) is
3113 Obj_Typ : constant Entity_Id := Etype (Obj_Id);
3114 AR_Val : Boolean := False;
3115 AW_Val : Boolean := False;
3116 ER_Val : Boolean := False;
3117 EW_Val : Boolean := False;
3119 Seen : Boolean := False;
3122 -- The loop parameter in an element iterator over a formal container
3123 -- is declared with an object declaration but no contracts apply.
3125 if Ekind (Obj_Id) = E_Loop_Parameter then
3129 if Ekind (Obj_Id) = E_Constant then
3131 -- A constant cannot be effectively volatile. This check is only
3132 -- relevant with SPARK_Mode on as it is not a standard Ada legality
3133 -- rule. Do not flag internally-generated constants that map generic
3134 -- formals to actuals in instantiations (SPARK RM 7.1.3(6)).
3137 and then Is_Effectively_Volatile (Obj_Id)
3138 and then No (Corresponding_Generic_Association (Parent (Obj_Id)))
3140 Error_Msg_N ("constant cannot be volatile", Obj_Id);
3143 else pragma Assert (Ekind (Obj_Id) = E_Variable);
3145 -- The following checks are only relevant when SPARK_Mode is on as
3146 -- they are not standard Ada legality rules. Internally generated
3147 -- temporaries are ignored.
3149 if SPARK_Mode = On and then Comes_From_Source (Obj_Id) then
3150 if Is_Effectively_Volatile (Obj_Id) then
3152 -- The declaration of an effectively volatile object must
3153 -- appear at the library level (SPARK RM 7.1.3(7), C.6(6)).
3155 if not Is_Library_Level_Entity (Obj_Id) then
3157 ("volatile variable & must be declared at library level",
3160 -- An object of a discriminated type cannot be effectively
3161 -- volatile (SPARK RM C.6(4)).
3163 elsif Has_Discriminants (Obj_Typ) then
3165 ("discriminated object & cannot be volatile", Obj_Id);
3167 -- An object of a tagged type cannot be effectively volatile
3168 -- (SPARK RM C.6(5)).
3170 elsif Is_Tagged_Type (Obj_Typ) then
3171 Error_Msg_N ("tagged object & cannot be volatile", Obj_Id);
3174 -- The object is not effectively volatile
3177 -- A non-effectively volatile object cannot have effectively
3178 -- volatile components (SPARK RM 7.1.3(7)).
3180 if not Is_Effectively_Volatile (Obj_Id)
3181 and then Has_Volatile_Component (Obj_Typ)
3184 ("non-volatile object & cannot have volatile components",
3190 if Is_Ghost_Entity (Obj_Id) then
3192 -- A Ghost object cannot be effectively volatile (SPARK RM 6.9(8))
3194 if Is_Effectively_Volatile (Obj_Id) then
3195 Error_Msg_N ("ghost variable & cannot be volatile", Obj_Id);
3197 -- A Ghost object cannot be imported or exported (SPARK RM 6.9(8))
3199 elsif Is_Imported (Obj_Id) then
3200 Error_Msg_N ("ghost object & cannot be imported", Obj_Id);
3202 elsif Is_Exported (Obj_Id) then
3203 Error_Msg_N ("ghost object & cannot be exported", Obj_Id);
3207 -- Analyze all external properties
3209 Prag := Get_Pragma (Obj_Id, Pragma_Async_Readers);
3211 if Present (Prag) then
3212 Analyze_External_Property_In_Decl_Part (Prag, AR_Val);
3216 Prag := Get_Pragma (Obj_Id, Pragma_Async_Writers);
3218 if Present (Prag) then
3219 Analyze_External_Property_In_Decl_Part (Prag, AW_Val);
3223 Prag := Get_Pragma (Obj_Id, Pragma_Effective_Reads);
3225 if Present (Prag) then
3226 Analyze_External_Property_In_Decl_Part (Prag, ER_Val);
3230 Prag := Get_Pragma (Obj_Id, Pragma_Effective_Writes);
3232 if Present (Prag) then
3233 Analyze_External_Property_In_Decl_Part (Prag, EW_Val);
3237 -- Verify the mutual interaction of the various external properties
3240 Check_External_Properties (Obj_Id, AR_Val, AW_Val, ER_Val, EW_Val);
3243 -- Check whether the lack of indicator Part_Of agrees with the
3244 -- placement of the variable with respect to the state space.
3246 Prag := Get_Pragma (Obj_Id, Pragma_Part_Of);
3249 Check_Missing_Part_Of (Obj_Id);
3253 -- A ghost object cannot be imported or exported (SPARK RM 6.9(8))
3255 if Is_Ghost_Entity (Obj_Id) then
3256 if Is_Exported (Obj_Id) then
3257 Error_Msg_N ("ghost object & cannot be exported", Obj_Id);
3259 elsif Is_Imported (Obj_Id) then
3260 Error_Msg_N ("ghost object & cannot be imported", Obj_Id);
3263 end Analyze_Object_Contract;
3265 --------------------------------
3266 -- Analyze_Object_Declaration --
3267 --------------------------------
3269 procedure Analyze_Object_Declaration (N : Node_Id) is
3270 Loc : constant Source_Ptr := Sloc (N);
3271 Id : constant Entity_Id := Defining_Identifier (N);
3275 E : Node_Id := Expression (N);
3276 -- E is set to Expression (N) throughout this routine. When
3277 -- Expression (N) is modified, E is changed accordingly.
3279 Prev_Entity : Entity_Id := Empty;
3281 function Count_Tasks (T : Entity_Id) return Uint;
3282 -- This function is called when a non-generic library level object of a
3283 -- task type is declared. Its function is to count the static number of
3284 -- tasks declared within the type (it is only called if Has_Tasks is set
3285 -- for T). As a side effect, if an array of tasks with non-static bounds
3286 -- or a variant record type is encountered, Check_Restrictions is called
3287 -- indicating the count is unknown.
3293 function Count_Tasks (T : Entity_Id) return Uint is
3299 if Is_Task_Type (T) then
3302 elsif Is_Record_Type (T) then
3303 if Has_Discriminants (T) then
3304 Check_Restriction (Max_Tasks, N);
3309 C := First_Component (T);
3310 while Present (C) loop
3311 V := V + Count_Tasks (Etype (C));
3318 elsif Is_Array_Type (T) then
3319 X := First_Index (T);
3320 V := Count_Tasks (Component_Type (T));
3321 while Present (X) loop
3324 if not Is_OK_Static_Subtype (C) then
3325 Check_Restriction (Max_Tasks, N);
3328 V := V * (UI_Max (Uint_0,
3329 Expr_Value (Type_High_Bound (C)) -
3330 Expr_Value (Type_Low_Bound (C)) + Uint_1));
3343 -- Start of processing for Analyze_Object_Declaration
3346 -- There are three kinds of implicit types generated by an
3347 -- object declaration:
3349 -- 1. Those generated by the original Object Definition
3351 -- 2. Those generated by the Expression
3353 -- 3. Those used to constrain the Object Definition with the
3354 -- expression constraints when the definition is unconstrained.
3356 -- They must be generated in this order to avoid order of elaboration
3357 -- issues. Thus the first step (after entering the name) is to analyze
3358 -- the object definition.
3360 if Constant_Present (N) then
3361 Prev_Entity := Current_Entity_In_Scope (Id);
3363 if Present (Prev_Entity)
3365 -- If the homograph is an implicit subprogram, it is overridden
3366 -- by the current declaration.
3368 ((Is_Overloadable (Prev_Entity)
3369 and then Is_Inherited_Operation (Prev_Entity))
3371 -- The current object is a discriminal generated for an entry
3372 -- family index. Even though the index is a constant, in this
3373 -- particular context there is no true constant redeclaration.
3374 -- Enter_Name will handle the visibility.
3377 (Is_Discriminal (Id)
3378 and then Ekind (Discriminal_Link (Id)) =
3379 E_Entry_Index_Parameter)
3381 -- The current object is the renaming for a generic declared
3382 -- within the instance.
3385 (Ekind (Prev_Entity) = E_Package
3386 and then Nkind (Parent (Prev_Entity)) =
3387 N_Package_Renaming_Declaration
3388 and then not Comes_From_Source (Prev_Entity)
3390 Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
3392 Prev_Entity := Empty;
3396 if Present (Prev_Entity) then
3397 Constant_Redeclaration (Id, N, T);
3399 Generate_Reference (Prev_Entity, Id, 'c');
3400 Set_Completion_Referenced (Id);
3402 if Error_Posted (N) then
3404 -- Type mismatch or illegal redeclaration, Do not analyze
3405 -- expression to avoid cascaded errors.
3407 T := Find_Type_Of_Object (Object_Definition (N), N);
3409 Set_Ekind (Id, E_Variable);
3413 -- In the normal case, enter identifier at the start to catch premature
3414 -- usage in the initialization expression.
3417 Generate_Definition (Id);
3420 Mark_Coextensions (N, Object_Definition (N));
3422 T := Find_Type_Of_Object (Object_Definition (N), N);
3424 if Nkind (Object_Definition (N)) = N_Access_Definition
3426 (Access_To_Subprogram_Definition (Object_Definition (N)))
3427 and then Protected_Present
3428 (Access_To_Subprogram_Definition (Object_Definition (N)))
3430 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
3433 if Error_Posted (Id) then
3435 Set_Ekind (Id, E_Variable);
3440 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
3441 -- out some static checks
3443 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (T) then
3445 -- In case of aggregates we must also take care of the correct
3446 -- initialization of nested aggregates bug this is done at the
3447 -- point of the analysis of the aggregate (see sem_aggr.adb).
3449 if Present (Expression (N))
3450 and then Nkind (Expression (N)) = N_Aggregate
3456 Save_Typ : constant Entity_Id := Etype (Id);
3458 Set_Etype (Id, T); -- Temp. decoration for static checks
3459 Null_Exclusion_Static_Checks (N);
3460 Set_Etype (Id, Save_Typ);
3465 -- Object is marked pure if it is in a pure scope
3467 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3469 -- If deferred constant, make sure context is appropriate. We detect
3470 -- a deferred constant as a constant declaration with no expression.
3471 -- A deferred constant can appear in a package body if its completion
3472 -- is by means of an interface pragma.
3474 if Constant_Present (N) and then No (E) then
3476 -- A deferred constant may appear in the declarative part of the
3477 -- following constructs:
3481 -- extended return statements
3484 -- subprogram bodies
3487 -- When declared inside a package spec, a deferred constant must be
3488 -- completed by a full constant declaration or pragma Import. In all
3489 -- other cases, the only proper completion is pragma Import. Extended
3490 -- return statements are flagged as invalid contexts because they do
3491 -- not have a declarative part and so cannot accommodate the pragma.
3493 if Ekind (Current_Scope) = E_Return_Statement then
3495 ("invalid context for deferred constant declaration (RM 7.4)",
3498 ("\declaration requires an initialization expression",
3500 Set_Constant_Present (N, False);
3502 -- In Ada 83, deferred constant must be of private type
3504 elsif not Is_Private_Type (T) then
3505 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
3507 ("(Ada 83) deferred constant must be private type", N);
3511 -- If not a deferred constant, then the object declaration freezes
3512 -- its type, unless the object is of an anonymous type and has delayed
3513 -- aspects. In that case the type is frozen when the object itself is.
3516 Check_Fully_Declared (T, N);
3518 if Has_Delayed_Aspects (Id)
3519 and then Is_Array_Type (T)
3520 and then Is_Itype (T)
3522 Set_Has_Delayed_Freeze (T);
3524 Freeze_Before (N, T);
3528 -- If the object was created by a constrained array definition, then
3529 -- set the link in both the anonymous base type and anonymous subtype
3530 -- that are built to represent the array type to point to the object.
3532 if Nkind (Object_Definition (Declaration_Node (Id))) =
3533 N_Constrained_Array_Definition
3535 Set_Related_Array_Object (T, Id);
3536 Set_Related_Array_Object (Base_Type (T), Id);
3539 -- Special checks for protected objects not at library level
3541 if Is_Protected_Type (T)
3542 and then not Is_Library_Level_Entity (Id)
3544 Check_Restriction (No_Local_Protected_Objects, Id);
3546 -- Protected objects with interrupt handlers must be at library level
3548 -- Ada 2005: This test is not needed (and the corresponding clause
3549 -- in the RM is removed) because accessibility checks are sufficient
3550 -- to make handlers not at the library level illegal.
3552 -- AI05-0303: The AI is in fact a binding interpretation, and thus
3553 -- applies to the '95 version of the language as well.
3555 if Has_Interrupt_Handler (T) and then Ada_Version < Ada_95 then
3557 ("interrupt object can only be declared at library level", Id);
3561 -- The actual subtype of the object is the nominal subtype, unless
3562 -- the nominal one is unconstrained and obtained from the expression.
3566 -- These checks should be performed before the initialization expression
3567 -- is considered, so that the Object_Definition node is still the same
3568 -- as in source code.
3570 -- In SPARK, the nominal subtype is always given by a subtype mark
3571 -- and must not be unconstrained. (The only exception to this is the
3572 -- acceptance of declarations of constants of type String.)
3574 if not Nkind_In (Object_Definition (N), N_Expanded_Name, N_Identifier)
3576 Check_SPARK_05_Restriction
3577 ("subtype mark required", Object_Definition (N));
3579 elsif Is_Array_Type (T)
3580 and then not Is_Constrained (T)
3581 and then T /= Standard_String
3583 Check_SPARK_05_Restriction
3584 ("subtype mark of constrained type expected",
3585 Object_Definition (N));
3588 -- There are no aliased objects in SPARK
3590 if Aliased_Present (N) then
3591 Check_SPARK_05_Restriction ("aliased object is not allowed", N);
3594 -- Process initialization expression if present and not in error
3596 if Present (E) and then E /= Error then
3598 -- Generate an error in case of CPP class-wide object initialization.
3599 -- Required because otherwise the expansion of the class-wide
3600 -- assignment would try to use 'size to initialize the object
3601 -- (primitive that is not available in CPP tagged types).
3603 if Is_Class_Wide_Type (Act_T)
3605 (Is_CPP_Class (Root_Type (Etype (Act_T)))
3607 (Present (Full_View (Root_Type (Etype (Act_T))))
3609 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
3612 ("predefined assignment not available for 'C'P'P tagged types",
3616 Mark_Coextensions (N, E);
3619 -- In case of errors detected in the analysis of the expression,
3620 -- decorate it with the expected type to avoid cascaded errors
3622 if No (Etype (E)) then
3626 -- If an initialization expression is present, then we set the
3627 -- Is_True_Constant flag. It will be reset if this is a variable
3628 -- and it is indeed modified.
3630 Set_Is_True_Constant (Id, True);
3632 -- If we are analyzing a constant declaration, set its completion
3633 -- flag after analyzing and resolving the expression.
3635 if Constant_Present (N) then
3636 Set_Has_Completion (Id);
3639 -- Set type and resolve (type may be overridden later on). Note:
3640 -- Ekind (Id) must still be E_Void at this point so that incorrect
3641 -- early usage within E is properly diagnosed.
3645 -- If the expression is an aggregate we must look ahead to detect
3646 -- the possible presence of an address clause, and defer resolution
3647 -- and expansion of the aggregate to the freeze point of the entity.
3649 if Comes_From_Source (N)
3650 and then Expander_Active
3651 and then Nkind (E) = N_Aggregate
3653 -- Note the importance of doing this the following test after the
3654 -- N_Aggregate test to avoid inefficiencies from too many calls to
3655 -- the function Following_Address_Clause which can be expensive.
3657 and then Present (Following_Address_Clause (N))
3665 -- No further action needed if E is a call to an inlined function
3666 -- which returns an unconstrained type and it has been expanded into
3667 -- a procedure call. In that case N has been replaced by an object
3668 -- declaration without initializing expression and it has been
3669 -- analyzed (see Expand_Inlined_Call).
3671 if Back_End_Inlining
3672 and then Expander_Active
3673 and then Nkind (E) = N_Function_Call
3674 and then Nkind (Name (E)) in N_Has_Entity
3675 and then Is_Inlined (Entity (Name (E)))
3676 and then not Is_Constrained (Etype (E))
3677 and then Analyzed (N)
3678 and then No (Expression (N))
3683 -- If E is null and has been replaced by an N_Raise_Constraint_Error
3684 -- node (which was marked already-analyzed), we need to set the type
3685 -- to something other than Any_Access in order to keep gigi happy.
3687 if Etype (E) = Any_Access then
3691 -- If the object is an access to variable, the initialization
3692 -- expression cannot be an access to constant.
3694 if Is_Access_Type (T)
3695 and then not Is_Access_Constant (T)
3696 and then Is_Access_Type (Etype (E))
3697 and then Is_Access_Constant (Etype (E))
3700 ("access to variable cannot be initialized with an "
3701 & "access-to-constant expression", E);
3704 if not Assignment_OK (N) then
3705 Check_Initialization (T, E);
3708 Check_Unset_Reference (E);
3710 -- If this is a variable, then set current value. If this is a
3711 -- declared constant of a scalar type with a static expression,
3712 -- indicate that it is always valid.
3714 if not Constant_Present (N) then
3715 if Compile_Time_Known_Value (E) then
3716 Set_Current_Value (Id, E);
3719 elsif Is_Scalar_Type (T) and then Is_OK_Static_Expression (E) then
3720 Set_Is_Known_Valid (Id);
3723 -- Deal with setting of null flags
3725 if Is_Access_Type (T) then
3726 if Known_Non_Null (E) then
3727 Set_Is_Known_Non_Null (Id, True);
3728 elsif Known_Null (E) and then not Can_Never_Be_Null (Id) then
3729 Set_Is_Known_Null (Id, True);
3733 -- Check incorrect use of dynamically tagged expressions
3735 if Is_Tagged_Type (T) then
3736 Check_Dynamically_Tagged_Expression
3742 Apply_Scalar_Range_Check (E, T);
3743 Apply_Static_Length_Check (E, T);
3745 if Nkind (Original_Node (N)) = N_Object_Declaration
3746 and then Comes_From_Source (Original_Node (N))
3748 -- Only call test if needed
3750 and then Restriction_Check_Required (SPARK_05)
3751 and then not Is_SPARK_05_Initialization_Expr (Original_Node (E))
3753 Check_SPARK_05_Restriction
3754 ("initialization expression is not appropriate", E);
3757 -- A formal parameter of a specific tagged type whose related
3758 -- subprogram is subject to pragma Extensions_Visible with value
3759 -- "False" cannot be implicitly converted to a class-wide type by
3760 -- means of an initialization expression (SPARK RM 6.1.7(3)).
3762 if Is_Class_Wide_Type (T) and then Is_EVF_Expression (E) then
3764 ("formal parameter with Extensions_Visible False cannot be "
3765 & "implicitly converted to class-wide type", E);
3769 -- If the No_Streams restriction is set, check that the type of the
3770 -- object is not, and does not contain, any subtype derived from
3771 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
3772 -- Has_Stream just for efficiency reasons. There is no point in
3773 -- spending time on a Has_Stream check if the restriction is not set.
3775 if Restriction_Check_Required (No_Streams) then
3776 if Has_Stream (T) then
3777 Check_Restriction (No_Streams, N);
3781 -- Deal with predicate check before we start to do major rewriting. It
3782 -- is OK to initialize and then check the initialized value, since the
3783 -- object goes out of scope if we get a predicate failure. Note that we
3784 -- do this in the analyzer and not the expander because the analyzer
3785 -- does some substantial rewriting in some cases.
3787 -- We need a predicate check if the type has predicates, and if either
3788 -- there is an initializing expression, or for default initialization
3789 -- when we have at least one case of an explicit default initial value
3790 -- and then this is not an internal declaration whose initialization
3791 -- comes later (as for an aggregate expansion).
3793 if not Suppress_Assignment_Checks (N)
3794 and then Present (Predicate_Function (T))
3795 and then not No_Initialization (N)
3799 Is_Partially_Initialized_Type (T, Include_Implicit => False))
3801 -- If the type has a static predicate and the expression is known at
3802 -- compile time, see if the expression satisfies the predicate.
3805 Check_Expression_Against_Static_Predicate (E, T);
3809 Make_Predicate_Check (T, New_Occurrence_Of (Id, Loc)));
3812 -- Case of unconstrained type
3814 if Is_Indefinite_Subtype (T) then
3816 -- In SPARK, a declaration of unconstrained type is allowed
3817 -- only for constants of type string.
3819 if Is_String_Type (T) and then not Constant_Present (N) then
3820 Check_SPARK_05_Restriction
3821 ("declaration of object of unconstrained type not allowed", N);
3824 -- Nothing to do in deferred constant case
3826 if Constant_Present (N) and then No (E) then
3829 -- Case of no initialization present
3832 if No_Initialization (N) then
3835 elsif Is_Class_Wide_Type (T) then
3837 ("initialization required in class-wide declaration ", N);
3841 ("unconstrained subtype not allowed (need initialization)",
3842 Object_Definition (N));
3844 if Is_Record_Type (T) and then Has_Discriminants (T) then
3846 ("\provide initial value or explicit discriminant values",
3847 Object_Definition (N));
3850 ("\or give default discriminant values for type&",
3851 Object_Definition (N), T);
3853 elsif Is_Array_Type (T) then
3855 ("\provide initial value or explicit array bounds",
3856 Object_Definition (N));
3860 -- Case of initialization present but in error. Set initial
3861 -- expression as absent (but do not make above complaints)
3863 elsif E = Error then
3864 Set_Expression (N, Empty);
3867 -- Case of initialization present
3870 -- Check restrictions in Ada 83
3872 if not Constant_Present (N) then
3874 -- Unconstrained variables not allowed in Ada 83 mode
3876 if Ada_Version = Ada_83
3877 and then Comes_From_Source (Object_Definition (N))
3880 ("(Ada 83) unconstrained variable not allowed",
3881 Object_Definition (N));
3885 -- Now we constrain the variable from the initializing expression
3887 -- If the expression is an aggregate, it has been expanded into
3888 -- individual assignments. Retrieve the actual type from the
3889 -- expanded construct.
3891 if Is_Array_Type (T)
3892 and then No_Initialization (N)
3893 and then Nkind (Original_Node (E)) = N_Aggregate
3897 -- In case of class-wide interface object declarations we delay
3898 -- the generation of the equivalent record type declarations until
3899 -- its expansion because there are cases in they are not required.
3901 elsif Is_Interface (T) then
3904 -- In GNATprove mode, Expand_Subtype_From_Expr does nothing. Thus,
3905 -- we should prevent the generation of another Itype with the
3906 -- same name as the one already generated, or we end up with
3907 -- two identical types in GNATprove.
3909 elsif GNATprove_Mode then
3912 -- If the type is an unchecked union, no subtype can be built from
3913 -- the expression. Rewrite declaration as a renaming, which the
3914 -- back-end can handle properly. This is a rather unusual case,
3915 -- because most unchecked_union declarations have default values
3916 -- for discriminants and are thus not indefinite.
3918 elsif Is_Unchecked_Union (T) then
3919 if Constant_Present (N) or else Nkind (E) = N_Function_Call then
3920 Set_Ekind (Id, E_Constant);
3922 Set_Ekind (Id, E_Variable);
3925 -- An object declared within a Ghost scope is automatically
3926 -- Ghost (SPARK RM 6.9(2)).
3928 if Comes_From_Source (Id) and then Within_Ghost_Scope then
3929 Set_Is_Ghost_Entity (Id);
3931 -- The Ghost policy in effect at the point of declaration
3932 -- and at the point of completion must match
3933 -- (SPARK RM 6.9(15)).
3935 if Present (Prev_Entity)
3936 and then Is_Ghost_Entity (Prev_Entity)
3938 Check_Ghost_Completion (Prev_Entity, Id);
3943 Make_Object_Renaming_Declaration (Loc,
3944 Defining_Identifier => Id,
3945 Subtype_Mark => New_Occurrence_Of (T, Loc),
3948 Set_Renamed_Object (Id, E);
3949 Freeze_Before (N, T);
3954 Expand_Subtype_From_Expr (N, T, Object_Definition (N), E);
3955 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
3958 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
3960 if Aliased_Present (N) then
3961 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3964 Freeze_Before (N, Act_T);
3965 Freeze_Before (N, T);
3968 elsif Is_Array_Type (T)
3969 and then No_Initialization (N)
3970 and then Nkind (Original_Node (E)) = N_Aggregate
3972 if not Is_Entity_Name (Object_Definition (N)) then
3974 Check_Compile_Time_Size (Act_T);
3976 if Aliased_Present (N) then
3977 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
3981 -- When the given object definition and the aggregate are specified
3982 -- independently, and their lengths might differ do a length check.
3983 -- This cannot happen if the aggregate is of the form (others =>...)
3985 if not Is_Constrained (T) then
3988 elsif Nkind (E) = N_Raise_Constraint_Error then
3990 -- Aggregate is statically illegal. Place back in declaration
3992 Set_Expression (N, E);
3993 Set_No_Initialization (N, False);
3995 elsif T = Etype (E) then
3998 elsif Nkind (E) = N_Aggregate
3999 and then Present (Component_Associations (E))
4000 and then Present (Choices (First (Component_Associations (E))))
4001 and then Nkind (First
4002 (Choices (First (Component_Associations (E))))) = N_Others_Choice
4007 Apply_Length_Check (E, T);
4010 -- If the type is limited unconstrained with defaulted discriminants and
4011 -- there is no expression, then the object is constrained by the
4012 -- defaults, so it is worthwhile building the corresponding subtype.
4014 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
4015 and then not Is_Constrained (T)
4016 and then Has_Discriminants (T)
4019 Act_T := Build_Default_Subtype (T, N);
4021 -- Ada 2005: A limited object may be initialized by means of an
4022 -- aggregate. If the type has default discriminants it has an
4023 -- unconstrained nominal type, Its actual subtype will be obtained
4024 -- from the aggregate, and not from the default discriminants.
4029 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
4031 elsif Nkind (E) = N_Function_Call
4032 and then Constant_Present (N)
4033 and then Has_Unconstrained_Elements (Etype (E))
4035 -- The back-end has problems with constants of a discriminated type
4036 -- with defaults, if the initial value is a function call. We
4037 -- generate an intermediate temporary that will receive a reference
4038 -- to the result of the call. The initialization expression then
4039 -- becomes a dereference of that temporary.
4041 Remove_Side_Effects (E);
4043 -- If this is a constant declaration of an unconstrained type and
4044 -- the initialization is an aggregate, we can use the subtype of the
4045 -- aggregate for the declared entity because it is immutable.
4047 elsif not Is_Constrained (T)
4048 and then Has_Discriminants (T)
4049 and then Constant_Present (N)
4050 and then not Has_Unchecked_Union (T)
4051 and then Nkind (E) = N_Aggregate
4056 -- Check No_Wide_Characters restriction
4058 Check_Wide_Character_Restriction (T, Object_Definition (N));
4060 -- Indicate this is not set in source. Certainly true for constants, and
4061 -- true for variables so far (will be reset for a variable if and when
4062 -- we encounter a modification in the source).
4064 Set_Never_Set_In_Source (Id);
4066 -- Now establish the proper kind and type of the object
4068 if Constant_Present (N) then
4069 Set_Ekind (Id, E_Constant);
4070 Set_Is_True_Constant (Id);
4073 Set_Ekind (Id, E_Variable);
4075 -- A variable is set as shared passive if it appears in a shared
4076 -- passive package, and is at the outer level. This is not done for
4077 -- entities generated during expansion, because those are always
4078 -- manipulated locally.
4080 if Is_Shared_Passive (Current_Scope)
4081 and then Is_Library_Level_Entity (Id)
4082 and then Comes_From_Source (Id)
4084 Set_Is_Shared_Passive (Id);
4085 Check_Shared_Var (Id, T, N);
4088 -- Set Has_Initial_Value if initializing expression present. Note
4089 -- that if there is no initializing expression, we leave the state
4090 -- of this flag unchanged (usually it will be False, but notably in
4091 -- the case of exception choice variables, it will already be true).
4094 Set_Has_Initial_Value (Id);
4097 Set_Contract (Id, Make_Contract (Sloc (Id)));
4100 -- Initialize alignment and size and capture alignment setting
4102 Init_Alignment (Id);
4104 Set_Optimize_Alignment_Flags (Id);
4106 -- An object declared within a Ghost scope is automatically Ghost
4107 -- (SPARK RM 6.9(2)). This property is also inherited when its type
4108 -- is Ghost or the previous declaration of the deferred constant is
4111 if Comes_From_Source (Id)
4112 and then (Is_Ghost_Entity (T)
4113 or else (Present (Prev_Entity)
4114 and then Is_Ghost_Entity (Prev_Entity))
4115 or else Within_Ghost_Scope)
4117 Set_Is_Ghost_Entity (Id);
4119 -- The Ghost policy in effect at the point of declaration and at the
4120 -- point of completion must match (SPARK RM 6.9(16)).
4122 if Present (Prev_Entity) and then Is_Ghost_Entity (Prev_Entity) then
4123 Check_Ghost_Completion (Prev_Entity, Id);
4127 -- Deal with aliased case
4129 if Aliased_Present (N) then
4130 Set_Is_Aliased (Id);
4132 -- If the object is aliased and the type is unconstrained with
4133 -- defaulted discriminants and there is no expression, then the
4134 -- object is constrained by the defaults, so it is worthwhile
4135 -- building the corresponding subtype.
4137 -- Ada 2005 (AI-363): If the aliased object is discriminated and
4138 -- unconstrained, then only establish an actual subtype if the
4139 -- nominal subtype is indefinite. In definite cases the object is
4140 -- unconstrained in Ada 2005.
4143 and then Is_Record_Type (T)
4144 and then not Is_Constrained (T)
4145 and then Has_Discriminants (T)
4146 and then (Ada_Version < Ada_2005 or else Is_Indefinite_Subtype (T))
4148 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
4152 -- Now we can set the type of the object
4154 Set_Etype (Id, Act_T);
4156 -- Non-constant object is marked to be treated as volatile if type is
4157 -- volatile and we clear the Current_Value setting that may have been
4158 -- set above. Doing so for constants isn't required and might interfere
4159 -- with possible uses of the object as a static expression in contexts
4160 -- incompatible with volatility (e.g. as a case-statement alternative).
4162 if Ekind (Id) /= E_Constant and then Treat_As_Volatile (Etype (Id)) then
4163 Set_Treat_As_Volatile (Id);
4164 Set_Current_Value (Id, Empty);
4167 -- Deal with controlled types
4169 if Has_Controlled_Component (Etype (Id))
4170 or else Is_Controlled (Etype (Id))
4172 if not Is_Library_Level_Entity (Id) then
4173 Check_Restriction (No_Nested_Finalization, N);
4175 Validate_Controlled_Object (Id);
4179 if Has_Task (Etype (Id)) then
4180 Check_Restriction (No_Tasking, N);
4182 -- Deal with counting max tasks
4184 -- Nothing to do if inside a generic
4186 if Inside_A_Generic then
4189 -- If library level entity, then count tasks
4191 elsif Is_Library_Level_Entity (Id) then
4192 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
4194 -- If not library level entity, then indicate we don't know max
4195 -- tasks and also check task hierarchy restriction and blocking
4196 -- operation (since starting a task is definitely blocking).
4199 Check_Restriction (Max_Tasks, N);
4200 Check_Restriction (No_Task_Hierarchy, N);
4201 Check_Potentially_Blocking_Operation (N);
4204 -- A rather specialized test. If we see two tasks being declared
4205 -- of the same type in the same object declaration, and the task
4206 -- has an entry with an address clause, we know that program error
4207 -- will be raised at run time since we can't have two tasks with
4208 -- entries at the same address.
4210 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
4215 E := First_Entity (Etype (Id));
4216 while Present (E) loop
4217 if Ekind (E) = E_Entry
4218 and then Present (Get_Attribute_Definition_Clause
4219 (E, Attribute_Address))
4221 Error_Msg_Warn := SPARK_Mode /= On;
4223 ("more than one task with same entry address<<", N);
4224 Error_Msg_N ("\Program_Error [<<", N);
4226 Make_Raise_Program_Error (Loc,
4227 Reason => PE_Duplicated_Entry_Address));
4237 -- Some simple constant-propagation: if the expression is a constant
4238 -- string initialized with a literal, share the literal. This avoids
4242 and then Is_Entity_Name (E)
4243 and then Ekind (Entity (E)) = E_Constant
4244 and then Base_Type (Etype (E)) = Standard_String
4247 Val : constant Node_Id := Constant_Value (Entity (E));
4249 if Present (Val) and then Nkind (Val) = N_String_Literal then
4250 Rewrite (E, New_Copy (Val));
4255 -- Another optimization: if the nominal subtype is unconstrained and
4256 -- the expression is a function call that returns an unconstrained
4257 -- type, rewrite the declaration as a renaming of the result of the
4258 -- call. The exceptions below are cases where the copy is expected,
4259 -- either by the back end (Aliased case) or by the semantics, as for
4260 -- initializing controlled types or copying tags for classwide types.
4263 and then Nkind (E) = N_Explicit_Dereference
4264 and then Nkind (Original_Node (E)) = N_Function_Call
4265 and then not Is_Library_Level_Entity (Id)
4266 and then not Is_Constrained (Underlying_Type (T))
4267 and then not Is_Aliased (Id)
4268 and then not Is_Class_Wide_Type (T)
4269 and then not Is_Controlled (T)
4270 and then not Has_Controlled_Component (Base_Type (T))
4271 and then Expander_Active
4274 Make_Object_Renaming_Declaration (Loc,
4275 Defining_Identifier => Id,
4276 Access_Definition => Empty,
4277 Subtype_Mark => New_Occurrence_Of
4278 (Base_Type (Etype (Id)), Loc),
4281 Set_Renamed_Object (Id, E);
4283 -- Force generation of debugging information for the constant and for
4284 -- the renamed function call.
4286 Set_Debug_Info_Needed (Id);
4287 Set_Debug_Info_Needed (Entity (Prefix (E)));
4290 if Present (Prev_Entity)
4291 and then Is_Frozen (Prev_Entity)
4292 and then not Error_Posted (Id)
4294 Error_Msg_N ("full constant declaration appears too late", N);
4297 Check_Eliminated (Id);
4299 -- Deal with setting In_Private_Part flag if in private part
4301 if Ekind (Scope (Id)) = E_Package and then In_Private_Part (Scope (Id))
4303 Set_In_Private_Part (Id);
4306 -- Check for violation of No_Local_Timing_Events
4308 if Restriction_Check_Required (No_Local_Timing_Events)
4309 and then not Is_Library_Level_Entity (Id)
4310 and then Is_RTE (Etype (Id), RE_Timing_Event)
4312 Check_Restriction (No_Local_Timing_Events, N);
4316 -- Initialize the refined state of a variable here because this is a
4317 -- common destination for legal and illegal object declarations.
4319 if Ekind (Id) = E_Variable then
4320 Set_Encapsulating_State (Id, Empty);
4323 if Has_Aspects (N) then
4324 Analyze_Aspect_Specifications (N, Id);
4327 Analyze_Dimension (N);
4329 -- Verify whether the object declaration introduces an illegal hidden
4330 -- state within a package subject to a null abstract state.
4332 if Ekind (Id) = E_Variable then
4333 Check_No_Hidden_State (Id);
4335 end Analyze_Object_Declaration;
4337 ---------------------------
4338 -- Analyze_Others_Choice --
4339 ---------------------------
4341 -- Nothing to do for the others choice node itself, the semantic analysis
4342 -- of the others choice will occur as part of the processing of the parent
4344 procedure Analyze_Others_Choice (N : Node_Id) is
4345 pragma Warnings (Off, N);
4348 end Analyze_Others_Choice;
4350 -------------------------------------------
4351 -- Analyze_Private_Extension_Declaration --
4352 -------------------------------------------
4354 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
4355 T : constant Entity_Id := Defining_Identifier (N);
4356 Indic : constant Node_Id := Subtype_Indication (N);
4357 Parent_Type : Entity_Id;
4358 Parent_Base : Entity_Id;
4361 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
4363 if Is_Non_Empty_List (Interface_List (N)) then
4369 Intf := First (Interface_List (N));
4370 while Present (Intf) loop
4371 T := Find_Type_Of_Subtype_Indic (Intf);
4373 Diagnose_Interface (Intf, T);
4379 Generate_Definition (T);
4381 -- For other than Ada 2012, just enter the name in the current scope
4383 if Ada_Version < Ada_2012 then
4386 -- Ada 2012 (AI05-0162): Enter the name in the current scope handling
4387 -- case of private type that completes an incomplete type.
4394 Prev := Find_Type_Name (N);
4396 pragma Assert (Prev = T
4397 or else (Ekind (Prev) = E_Incomplete_Type
4398 and then Present (Full_View (Prev))
4399 and then Full_View (Prev) = T));
4403 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
4404 Parent_Base := Base_Type (Parent_Type);
4406 if Parent_Type = Any_Type or else Etype (Parent_Type) = Any_Type then
4407 Set_Ekind (T, Ekind (Parent_Type));
4408 Set_Etype (T, Any_Type);
4411 elsif not Is_Tagged_Type (Parent_Type) then
4413 ("parent of type extension must be a tagged type ", Indic);
4416 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
4417 Error_Msg_N ("premature derivation of incomplete type", Indic);
4420 elsif Is_Concurrent_Type (Parent_Type) then
4422 ("parent type of a private extension cannot be "
4423 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
4425 Set_Etype (T, Any_Type);
4426 Set_Ekind (T, E_Limited_Private_Type);
4427 Set_Private_Dependents (T, New_Elmt_List);
4428 Set_Error_Posted (T);
4432 -- Perhaps the parent type should be changed to the class-wide type's
4433 -- specific type in this case to prevent cascading errors ???
4435 if Is_Class_Wide_Type (Parent_Type) then
4437 ("parent of type extension must not be a class-wide type", Indic);
4441 if (not Is_Package_Or_Generic_Package (Current_Scope)
4442 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
4443 or else In_Private_Part (Current_Scope)
4446 Error_Msg_N ("invalid context for private extension", N);
4449 -- Set common attributes
4451 Set_Is_Pure (T, Is_Pure (Current_Scope));
4452 Set_Scope (T, Current_Scope);
4453 Set_Ekind (T, E_Record_Type_With_Private);
4454 Init_Size_Align (T);
4455 Set_Default_SSO (T);
4457 Set_Etype (T, Parent_Base);
4458 Set_Has_Task (T, Has_Task (Parent_Base));
4459 Set_Has_Protected (T, Has_Task (Parent_Base));
4461 Set_Convention (T, Convention (Parent_Type));
4462 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
4463 Set_Is_First_Subtype (T);
4464 Make_Class_Wide_Type (T);
4466 if Unknown_Discriminants_Present (N) then
4467 Set_Discriminant_Constraint (T, No_Elist);
4470 Build_Derived_Record_Type (N, Parent_Type, T);
4472 -- Propagate inherited invariant information. The new type has
4473 -- invariants, if the parent type has inheritable invariants,
4474 -- and these invariants can in turn be inherited.
4476 if Has_Inheritable_Invariants (Parent_Type) then
4477 Set_Has_Inheritable_Invariants (T);
4478 Set_Has_Invariants (T);
4481 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
4482 -- synchronized formal derived type.
4484 if Ada_Version >= Ada_2005 and then Synchronized_Present (N) then
4485 Set_Is_Limited_Record (T);
4487 -- Formal derived type case
4489 if Is_Generic_Type (T) then
4491 -- The parent must be a tagged limited type or a synchronized
4494 if (not Is_Tagged_Type (Parent_Type)
4495 or else not Is_Limited_Type (Parent_Type))
4497 (not Is_Interface (Parent_Type)
4498 or else not Is_Synchronized_Interface (Parent_Type))
4500 Error_Msg_NE ("parent type of & must be tagged limited " &
4501 "or synchronized", N, T);
4504 -- The progenitors (if any) must be limited or synchronized
4507 if Present (Interfaces (T)) then
4510 Iface_Elmt : Elmt_Id;
4513 Iface_Elmt := First_Elmt (Interfaces (T));
4514 while Present (Iface_Elmt) loop
4515 Iface := Node (Iface_Elmt);
4517 if not Is_Limited_Interface (Iface)
4518 and then not Is_Synchronized_Interface (Iface)
4520 Error_Msg_NE ("progenitor & must be limited " &
4521 "or synchronized", N, Iface);
4524 Next_Elmt (Iface_Elmt);
4529 -- Regular derived extension, the parent must be a limited or
4530 -- synchronized interface.
4533 if not Is_Interface (Parent_Type)
4534 or else (not Is_Limited_Interface (Parent_Type)
4535 and then not Is_Synchronized_Interface (Parent_Type))
4538 ("parent type of & must be limited interface", N, T);
4542 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
4543 -- extension with a synchronized parent must be explicitly declared
4544 -- synchronized, because the full view will be a synchronized type.
4545 -- This must be checked before the check for limited types below,
4546 -- to ensure that types declared limited are not allowed to extend
4547 -- synchronized interfaces.
4549 elsif Is_Interface (Parent_Type)
4550 and then Is_Synchronized_Interface (Parent_Type)
4551 and then not Synchronized_Present (N)
4554 ("private extension of& must be explicitly synchronized",
4557 elsif Limited_Present (N) then
4558 Set_Is_Limited_Record (T);
4560 if not Is_Limited_Type (Parent_Type)
4562 (not Is_Interface (Parent_Type)
4563 or else not Is_Limited_Interface (Parent_Type))
4565 Error_Msg_NE ("parent type& of limited extension must be limited",
4571 if Has_Aspects (N) then
4572 Analyze_Aspect_Specifications (N, T);
4574 end Analyze_Private_Extension_Declaration;
4576 ---------------------------------
4577 -- Analyze_Subtype_Declaration --
4578 ---------------------------------
4580 procedure Analyze_Subtype_Declaration
4582 Skip : Boolean := False)
4584 Id : constant Entity_Id := Defining_Identifier (N);
4586 R_Checks : Check_Result;
4589 Generate_Definition (Id);
4590 Set_Is_Pure (Id, Is_Pure (Current_Scope));
4591 Init_Size_Align (Id);
4593 -- The following guard condition on Enter_Name is to handle cases where
4594 -- the defining identifier has already been entered into the scope but
4595 -- the declaration as a whole needs to be analyzed.
4597 -- This case in particular happens for derived enumeration types. The
4598 -- derived enumeration type is processed as an inserted enumeration type
4599 -- declaration followed by a rewritten subtype declaration. The defining
4600 -- identifier, however, is entered into the name scope very early in the
4601 -- processing of the original type declaration and therefore needs to be
4602 -- avoided here, when the created subtype declaration is analyzed. (See
4603 -- Build_Derived_Types)
4605 -- This also happens when the full view of a private type is derived
4606 -- type with constraints. In this case the entity has been introduced
4607 -- in the private declaration.
4609 -- Finally this happens in some complex cases when validity checks are
4610 -- enabled, where the same subtype declaration may be analyzed twice.
4611 -- This can happen if the subtype is created by the pre-analysis of
4612 -- an attribute tht gives the range of a loop statement, and the loop
4613 -- itself appears within an if_statement that will be rewritten during
4617 or else (Present (Etype (Id))
4618 and then (Is_Private_Type (Etype (Id))
4619 or else Is_Task_Type (Etype (Id))
4620 or else Is_Rewrite_Substitution (N)))
4624 elsif Current_Entity (Id) = Id then
4631 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
4633 -- Class-wide equivalent types of records with unknown discriminants
4634 -- involve the generation of an itype which serves as the private view
4635 -- of a constrained record subtype. In such cases the base type of the
4636 -- current subtype we are processing is the private itype. Use the full
4637 -- of the private itype when decorating various attributes.
4640 and then Is_Private_Type (T)
4641 and then Present (Full_View (T))
4646 -- Inherit common attributes
4648 Set_Is_Volatile (Id, Is_Volatile (T));
4649 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
4650 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
4651 Set_Convention (Id, Convention (T));
4653 -- If ancestor has predicates then so does the subtype, and in addition
4654 -- we must delay the freeze to properly arrange predicate inheritance.
4656 -- The Ancestor_Type test is really unpleasant, there seem to be cases
4657 -- in which T = ID, so the above tests and assignments do nothing???
4659 if Has_Predicates (T)
4660 or else (Present (Ancestor_Subtype (T))
4661 and then Has_Predicates (Ancestor_Subtype (T)))
4663 Set_Has_Predicates (Id);
4664 Set_Has_Delayed_Freeze (Id);
4667 -- Subtype of Boolean cannot have a constraint in SPARK
4669 if Is_Boolean_Type (T)
4670 and then Nkind (Subtype_Indication (N)) = N_Subtype_Indication
4672 Check_SPARK_05_Restriction
4673 ("subtype of Boolean cannot have constraint", N);
4676 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
4678 Cstr : constant Node_Id := Constraint (Subtype_Indication (N));
4684 if Nkind (Cstr) = N_Index_Or_Discriminant_Constraint then
4685 One_Cstr := First (Constraints (Cstr));
4686 while Present (One_Cstr) loop
4688 -- Index or discriminant constraint in SPARK must be a
4692 Nkind_In (One_Cstr, N_Identifier, N_Expanded_Name)
4694 Check_SPARK_05_Restriction
4695 ("subtype mark required", One_Cstr);
4697 -- String subtype must have a lower bound of 1 in SPARK.
4698 -- Note that we do not need to test for the non-static case
4699 -- here, since that was already taken care of in
4700 -- Process_Range_Expr_In_Decl.
4702 elsif Base_Type (T) = Standard_String then
4703 Get_Index_Bounds (One_Cstr, Low, High);
4705 if Is_OK_Static_Expression (Low)
4706 and then Expr_Value (Low) /= 1
4708 Check_SPARK_05_Restriction
4709 ("String subtype must have lower bound of 1", N);
4719 -- In the case where there is no constraint given in the subtype
4720 -- indication, Process_Subtype just returns the Subtype_Mark, so its
4721 -- semantic attributes must be established here.
4723 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
4724 Set_Etype (Id, Base_Type (T));
4726 -- Subtype of unconstrained array without constraint is not allowed
4729 if Is_Array_Type (T) and then not Is_Constrained (T) then
4730 Check_SPARK_05_Restriction
4731 ("subtype of unconstrained array must have constraint", N);
4736 Set_Ekind (Id, E_Array_Subtype);
4737 Copy_Array_Subtype_Attributes (Id, T);
4739 when Decimal_Fixed_Point_Kind =>
4740 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
4741 Set_Digits_Value (Id, Digits_Value (T));
4742 Set_Delta_Value (Id, Delta_Value (T));
4743 Set_Scale_Value (Id, Scale_Value (T));
4744 Set_Small_Value (Id, Small_Value (T));
4745 Set_Scalar_Range (Id, Scalar_Range (T));
4746 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
4747 Set_Is_Constrained (Id, Is_Constrained (T));
4748 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4749 Set_RM_Size (Id, RM_Size (T));
4751 when Enumeration_Kind =>
4752 Set_Ekind (Id, E_Enumeration_Subtype);
4753 Set_First_Literal (Id, First_Literal (Base_Type (T)));
4754 Set_Scalar_Range (Id, Scalar_Range (T));
4755 Set_Is_Character_Type (Id, Is_Character_Type (T));
4756 Set_Is_Constrained (Id, Is_Constrained (T));
4757 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4758 Set_RM_Size (Id, RM_Size (T));
4759 Inherit_Predicate_Flags (Id, T);
4761 when Ordinary_Fixed_Point_Kind =>
4762 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
4763 Set_Scalar_Range (Id, Scalar_Range (T));
4764 Set_Small_Value (Id, Small_Value (T));
4765 Set_Delta_Value (Id, Delta_Value (T));
4766 Set_Is_Constrained (Id, Is_Constrained (T));
4767 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4768 Set_RM_Size (Id, RM_Size (T));
4771 Set_Ekind (Id, E_Floating_Point_Subtype);
4772 Set_Scalar_Range (Id, Scalar_Range (T));
4773 Set_Digits_Value (Id, Digits_Value (T));
4774 Set_Is_Constrained (Id, Is_Constrained (T));
4776 when Signed_Integer_Kind =>
4777 Set_Ekind (Id, E_Signed_Integer_Subtype);
4778 Set_Scalar_Range (Id, Scalar_Range (T));
4779 Set_Is_Constrained (Id, Is_Constrained (T));
4780 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4781 Set_RM_Size (Id, RM_Size (T));
4782 Inherit_Predicate_Flags (Id, T);
4784 when Modular_Integer_Kind =>
4785 Set_Ekind (Id, E_Modular_Integer_Subtype);
4786 Set_Scalar_Range (Id, Scalar_Range (T));
4787 Set_Is_Constrained (Id, Is_Constrained (T));
4788 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
4789 Set_RM_Size (Id, RM_Size (T));
4790 Inherit_Predicate_Flags (Id, T);
4792 when Class_Wide_Kind =>
4793 Set_Ekind (Id, E_Class_Wide_Subtype);
4794 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4795 Set_Cloned_Subtype (Id, T);
4796 Set_Is_Tagged_Type (Id, True);
4797 Set_Has_Unknown_Discriminants
4799 Set_No_Tagged_Streams_Pragma
4800 (Id, No_Tagged_Streams_Pragma (T));
4802 if Ekind (T) = E_Class_Wide_Subtype then
4803 Set_Equivalent_Type (Id, Equivalent_Type (T));
4806 when E_Record_Type | E_Record_Subtype =>
4807 Set_Ekind (Id, E_Record_Subtype);
4809 if Ekind (T) = E_Record_Subtype
4810 and then Present (Cloned_Subtype (T))
4812 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
4814 Set_Cloned_Subtype (Id, T);
4817 Set_First_Entity (Id, First_Entity (T));
4818 Set_Last_Entity (Id, Last_Entity (T));
4819 Set_Has_Discriminants (Id, Has_Discriminants (T));
4820 Set_Is_Constrained (Id, Is_Constrained (T));
4821 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4822 Set_Has_Implicit_Dereference
4823 (Id, Has_Implicit_Dereference (T));
4824 Set_Has_Unknown_Discriminants
4825 (Id, Has_Unknown_Discriminants (T));
4827 if Has_Discriminants (T) then
4828 Set_Discriminant_Constraint
4829 (Id, Discriminant_Constraint (T));
4830 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4832 elsif Has_Unknown_Discriminants (Id) then
4833 Set_Discriminant_Constraint (Id, No_Elist);
4836 if Is_Tagged_Type (T) then
4837 Set_Is_Tagged_Type (Id, True);
4838 Set_No_Tagged_Streams_Pragma
4839 (Id, No_Tagged_Streams_Pragma (T));
4840 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4841 Set_Direct_Primitive_Operations
4842 (Id, Direct_Primitive_Operations (T));
4843 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4845 if Is_Interface (T) then
4846 Set_Is_Interface (Id);
4847 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
4851 when Private_Kind =>
4852 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4853 Set_Has_Discriminants (Id, Has_Discriminants (T));
4854 Set_Is_Constrained (Id, Is_Constrained (T));
4855 Set_First_Entity (Id, First_Entity (T));
4856 Set_Last_Entity (Id, Last_Entity (T));
4857 Set_Private_Dependents (Id, New_Elmt_List);
4858 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
4859 Set_Has_Implicit_Dereference
4860 (Id, Has_Implicit_Dereference (T));
4861 Set_Has_Unknown_Discriminants
4862 (Id, Has_Unknown_Discriminants (T));
4863 Set_Known_To_Have_Preelab_Init
4864 (Id, Known_To_Have_Preelab_Init (T));
4866 if Is_Tagged_Type (T) then
4867 Set_Is_Tagged_Type (Id);
4868 Set_No_Tagged_Streams_Pragma (Id,
4869 No_Tagged_Streams_Pragma (T));
4870 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
4871 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
4872 Set_Direct_Primitive_Operations (Id,
4873 Direct_Primitive_Operations (T));
4876 -- In general the attributes of the subtype of a private type
4877 -- are the attributes of the partial view of parent. However,
4878 -- the full view may be a discriminated type, and the subtype
4879 -- must share the discriminant constraint to generate correct
4880 -- calls to initialization procedures.
4882 if Has_Discriminants (T) then
4883 Set_Discriminant_Constraint
4884 (Id, Discriminant_Constraint (T));
4885 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4887 elsif Present (Full_View (T))
4888 and then Has_Discriminants (Full_View (T))
4890 Set_Discriminant_Constraint
4891 (Id, Discriminant_Constraint (Full_View (T)));
4892 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4894 -- This would seem semantically correct, but apparently
4895 -- generates spurious errors about missing components ???
4897 -- Set_Has_Discriminants (Id);
4900 Prepare_Private_Subtype_Completion (Id, N);
4902 -- If this is the subtype of a constrained private type with
4903 -- discriminants that has got a full view and we also have
4904 -- built a completion just above, show that the completion
4905 -- is a clone of the full view to the back-end.
4907 if Has_Discriminants (T)
4908 and then not Has_Unknown_Discriminants (T)
4909 and then not Is_Empty_Elmt_List (Discriminant_Constraint (T))
4910 and then Present (Full_View (T))
4911 and then Present (Full_View (Id))
4913 Set_Cloned_Subtype (Full_View (Id), Full_View (T));
4917 Set_Ekind (Id, E_Access_Subtype);
4918 Set_Is_Constrained (Id, Is_Constrained (T));
4919 Set_Is_Access_Constant
4920 (Id, Is_Access_Constant (T));
4921 Set_Directly_Designated_Type
4922 (Id, Designated_Type (T));
4923 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
4925 -- A Pure library_item must not contain the declaration of a
4926 -- named access type, except within a subprogram, generic
4927 -- subprogram, task unit, or protected unit, or if it has
4928 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
4930 if Comes_From_Source (Id)
4931 and then In_Pure_Unit
4932 and then not In_Subprogram_Task_Protected_Unit
4933 and then not No_Pool_Assigned (Id)
4936 ("named access types not allowed in pure unit", N);
4939 when Concurrent_Kind =>
4940 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
4941 Set_Corresponding_Record_Type (Id,
4942 Corresponding_Record_Type (T));
4943 Set_First_Entity (Id, First_Entity (T));
4944 Set_First_Private_Entity (Id, First_Private_Entity (T));
4945 Set_Has_Discriminants (Id, Has_Discriminants (T));
4946 Set_Is_Constrained (Id, Is_Constrained (T));
4947 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4948 Set_Last_Entity (Id, Last_Entity (T));
4950 if Is_Tagged_Type (T) then
4951 Set_No_Tagged_Streams_Pragma
4952 (Id, No_Tagged_Streams_Pragma (T));
4955 if Has_Discriminants (T) then
4956 Set_Discriminant_Constraint (Id,
4957 Discriminant_Constraint (T));
4958 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
4961 when E_Incomplete_Type =>
4962 if Ada_Version >= Ada_2005 then
4964 -- In Ada 2005 an incomplete type can be explicitly tagged:
4965 -- propagate indication.
4967 Set_Ekind (Id, E_Incomplete_Subtype);
4968 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
4969 Set_Private_Dependents (Id, New_Elmt_List);
4971 if Is_Tagged_Type (Id) then
4972 Set_No_Tagged_Streams_Pragma
4973 (Id, No_Tagged_Streams_Pragma (T));
4976 -- Ada 2005 (AI-412): Decorate an incomplete subtype of an
4977 -- incomplete type visible through a limited with clause.
4979 if From_Limited_With (T)
4980 and then Present (Non_Limited_View (T))
4982 Set_From_Limited_With (Id);
4983 Set_Non_Limited_View (Id, Non_Limited_View (T));
4985 -- Ada 2005 (AI-412): Add the regular incomplete subtype
4986 -- to the private dependents of the original incomplete
4987 -- type for future transformation.
4990 Append_Elmt (Id, Private_Dependents (T));
4993 -- If the subtype name denotes an incomplete type an error
4994 -- was already reported by Process_Subtype.
4997 Set_Etype (Id, Any_Type);
5001 raise Program_Error;
5005 if Etype (Id) = Any_Type then
5009 -- Some common processing on all types
5011 Set_Size_Info (Id, T);
5012 Set_First_Rep_Item (Id, First_Rep_Item (T));
5014 -- If the parent type is a generic actual, so is the subtype. This may
5015 -- happen in a nested instance. Why Comes_From_Source test???
5017 if not Comes_From_Source (N) then
5018 Set_Is_Generic_Actual_Type (Id, Is_Generic_Actual_Type (T));
5023 Set_Is_Immediately_Visible (Id, True);
5024 Set_Depends_On_Private (Id, Has_Private_Component (T));
5025 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
5027 if Is_Interface (T) then
5028 Set_Is_Interface (Id);
5031 if Present (Generic_Parent_Type (N))
5033 (Nkind (Parent (Generic_Parent_Type (N))) /=
5034 N_Formal_Type_Declaration
5035 or else Nkind (Formal_Type_Definition
5036 (Parent (Generic_Parent_Type (N)))) /=
5037 N_Formal_Private_Type_Definition)
5039 if Is_Tagged_Type (Id) then
5041 -- If this is a generic actual subtype for a synchronized type,
5042 -- the primitive operations are those of the corresponding record
5043 -- for which there is a separate subtype declaration.
5045 if Is_Concurrent_Type (Id) then
5047 elsif Is_Class_Wide_Type (Id) then
5048 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
5050 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
5053 elsif Scope (Etype (Id)) /= Standard_Standard then
5054 Derive_Subprograms (Generic_Parent_Type (N), Id);
5058 if Is_Private_Type (T) and then Present (Full_View (T)) then
5059 Conditional_Delay (Id, Full_View (T));
5061 -- The subtypes of components or subcomponents of protected types
5062 -- do not need freeze nodes, which would otherwise appear in the
5063 -- wrong scope (before the freeze node for the protected type). The
5064 -- proper subtypes are those of the subcomponents of the corresponding
5067 elsif Ekind (Scope (Id)) /= E_Protected_Type
5068 and then Present (Scope (Scope (Id))) -- error defense
5069 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
5071 Conditional_Delay (Id, T);
5074 -- Check that Constraint_Error is raised for a scalar subtype indication
5075 -- when the lower or upper bound of a non-null range lies outside the
5076 -- range of the type mark.
5078 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
5079 if Is_Scalar_Type (Etype (Id))
5080 and then Scalar_Range (Id) /=
5081 Scalar_Range (Etype (Subtype_Mark
5082 (Subtype_Indication (N))))
5086 Etype (Subtype_Mark (Subtype_Indication (N))));
5088 -- In the array case, check compatibility for each index
5090 elsif Is_Array_Type (Etype (Id)) and then Present (First_Index (Id))
5092 -- This really should be a subprogram that finds the indications
5096 Subt_Index : Node_Id := First_Index (Id);
5097 Target_Index : Node_Id :=
5099 (Subtype_Mark (Subtype_Indication (N))));
5100 Has_Dyn_Chk : Boolean := Has_Dynamic_Range_Check (N);
5103 while Present (Subt_Index) loop
5104 if ((Nkind (Subt_Index) = N_Identifier
5105 and then Ekind (Entity (Subt_Index)) in Scalar_Kind)
5106 or else Nkind (Subt_Index) = N_Subtype_Indication)
5108 Nkind (Scalar_Range (Etype (Subt_Index))) = N_Range
5111 Target_Typ : constant Entity_Id :=
5112 Etype (Target_Index);
5116 (Scalar_Range (Etype (Subt_Index)),
5119 Defining_Identifier (N));
5121 -- Reset Has_Dynamic_Range_Check on the subtype to
5122 -- prevent elision of the index check due to a dynamic
5123 -- check generated for a preceding index (needed since
5124 -- Insert_Range_Checks tries to avoid generating
5125 -- redundant checks on a given declaration).
5127 Set_Has_Dynamic_Range_Check (N, False);
5133 Sloc (Defining_Identifier (N)));
5135 -- Record whether this index involved a dynamic check
5138 Has_Dyn_Chk or else Has_Dynamic_Range_Check (N);
5142 Next_Index (Subt_Index);
5143 Next_Index (Target_Index);
5146 -- Finally, mark whether the subtype involves dynamic checks
5148 Set_Has_Dynamic_Range_Check (N, Has_Dyn_Chk);
5153 -- A type invariant applies to any subtype in its scope, in particular
5154 -- to a generic actual.
5156 if Has_Invariants (T) and then In_Open_Scopes (Scope (T)) then
5157 Set_Has_Invariants (Id);
5158 Set_Invariant_Procedure (Id, Invariant_Procedure (T));
5161 -- Make sure that generic actual types are properly frozen. The subtype
5162 -- is marked as a generic actual type when the enclosing instance is
5163 -- analyzed, so here we identify the subtype from the tree structure.
5166 and then Is_Generic_Actual_Type (Id)
5167 and then In_Instance
5168 and then not Comes_From_Source (N)
5169 and then Nkind (Subtype_Indication (N)) /= N_Subtype_Indication
5170 and then Is_Frozen (T)
5172 Freeze_Before (N, Id);
5175 Set_Optimize_Alignment_Flags (Id);
5176 Check_Eliminated (Id);
5179 if Has_Aspects (N) then
5180 Analyze_Aspect_Specifications (N, Id);
5183 Analyze_Dimension (N);
5184 end Analyze_Subtype_Declaration;
5186 --------------------------------
5187 -- Analyze_Subtype_Indication --
5188 --------------------------------
5190 procedure Analyze_Subtype_Indication (N : Node_Id) is
5191 T : constant Entity_Id := Subtype_Mark (N);
5192 R : constant Node_Id := Range_Expression (Constraint (N));
5199 Set_Etype (N, Etype (R));
5200 Resolve (R, Entity (T));
5202 Set_Error_Posted (R);
5203 Set_Error_Posted (T);
5205 end Analyze_Subtype_Indication;
5207 --------------------------
5208 -- Analyze_Variant_Part --
5209 --------------------------
5211 procedure Analyze_Variant_Part (N : Node_Id) is
5212 Discr_Name : Node_Id;
5213 Discr_Type : Entity_Id;
5215 procedure Process_Variant (A : Node_Id);
5216 -- Analyze declarations for a single variant
5218 package Analyze_Variant_Choices is
5219 new Generic_Analyze_Choices (Process_Variant);
5220 use Analyze_Variant_Choices;
5222 ---------------------
5223 -- Process_Variant --
5224 ---------------------
5226 procedure Process_Variant (A : Node_Id) is
5227 CL : constant Node_Id := Component_List (A);
5229 if not Null_Present (CL) then
5230 Analyze_Declarations (Component_Items (CL));
5232 if Present (Variant_Part (CL)) then
5233 Analyze (Variant_Part (CL));
5236 end Process_Variant;
5238 -- Start of processing for Analyze_Variant_Part
5241 Discr_Name := Name (N);
5242 Analyze (Discr_Name);
5244 -- If Discr_Name bad, get out (prevent cascaded errors)
5246 if Etype (Discr_Name) = Any_Type then
5250 -- Check invalid discriminant in variant part
5252 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
5253 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
5256 Discr_Type := Etype (Entity (Discr_Name));
5258 if not Is_Discrete_Type (Discr_Type) then
5260 ("discriminant in a variant part must be of a discrete type",
5265 -- Now analyze the choices, which also analyzes the declarations that
5266 -- are associated with each choice.
5268 Analyze_Choices (Variants (N), Discr_Type);
5270 -- Note: we used to instantiate and call Check_Choices here to check
5271 -- that the choices covered the discriminant, but it's too early to do
5272 -- that because of statically predicated subtypes, whose analysis may
5273 -- be deferred to their freeze point which may be as late as the freeze
5274 -- point of the containing record. So this call is now to be found in
5275 -- Freeze_Record_Declaration.
5277 end Analyze_Variant_Part;
5279 ----------------------------
5280 -- Array_Type_Declaration --
5281 ----------------------------
5283 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
5284 Component_Def : constant Node_Id := Component_Definition (Def);
5285 Component_Typ : constant Node_Id := Subtype_Indication (Component_Def);
5286 Element_Type : Entity_Id;
5287 Implicit_Base : Entity_Id;
5289 Related_Id : Entity_Id := Empty;
5291 P : constant Node_Id := Parent (Def);
5295 if Nkind (Def) = N_Constrained_Array_Definition then
5296 Index := First (Discrete_Subtype_Definitions (Def));
5298 Index := First (Subtype_Marks (Def));
5301 -- Find proper names for the implicit types which may be public. In case
5302 -- of anonymous arrays we use the name of the first object of that type
5306 Related_Id := Defining_Identifier (P);
5312 while Present (Index) loop
5315 -- Test for odd case of trying to index a type by the type itself
5317 if Is_Entity_Name (Index) and then Entity (Index) = T then
5318 Error_Msg_N ("type& cannot be indexed by itself", Index);
5319 Set_Entity (Index, Standard_Boolean);
5320 Set_Etype (Index, Standard_Boolean);
5323 -- Check SPARK restriction requiring a subtype mark
5325 if not Nkind_In (Index, N_Identifier, N_Expanded_Name) then
5326 Check_SPARK_05_Restriction ("subtype mark required", Index);
5329 -- Add a subtype declaration for each index of private array type
5330 -- declaration whose etype is also private. For example:
5333 -- type Index is private;
5335 -- type Table is array (Index) of ...
5338 -- This is currently required by the expander for the internally
5339 -- generated equality subprogram of records with variant parts in
5340 -- which the etype of some component is such private type.
5342 if Ekind (Current_Scope) = E_Package
5343 and then In_Private_Part (Current_Scope)
5344 and then Has_Private_Declaration (Etype (Index))
5347 Loc : constant Source_Ptr := Sloc (Def);
5352 New_E := Make_Temporary (Loc, 'T');
5353 Set_Is_Internal (New_E);
5356 Make_Subtype_Declaration (Loc,
5357 Defining_Identifier => New_E,
5358 Subtype_Indication =>
5359 New_Occurrence_Of (Etype (Index), Loc));
5361 Insert_Before (Parent (Def), Decl);
5363 Set_Etype (Index, New_E);
5365 -- If the index is a range the Entity attribute is not
5366 -- available. Example:
5369 -- type T is private;
5371 -- type T is new Natural;
5372 -- Table : array (T(1) .. T(10)) of Boolean;
5375 if Nkind (Index) /= N_Range then
5376 Set_Entity (Index, New_E);
5381 Make_Index (Index, P, Related_Id, Nb_Index);
5383 -- Check error of subtype with predicate for index type
5385 Bad_Predicated_Subtype_Use
5386 ("subtype& has predicate, not allowed as index subtype",
5387 Index, Etype (Index));
5389 -- Move to next index
5392 Nb_Index := Nb_Index + 1;
5395 -- Process subtype indication if one is present
5397 if Present (Component_Typ) then
5398 Element_Type := Process_Subtype (Component_Typ, P, Related_Id, 'C');
5400 Set_Etype (Component_Typ, Element_Type);
5402 if not Nkind_In (Component_Typ, N_Identifier, N_Expanded_Name) then
5403 Check_SPARK_05_Restriction
5404 ("subtype mark required", Component_Typ);
5407 -- Ada 2005 (AI-230): Access Definition case
5409 else pragma Assert (Present (Access_Definition (Component_Def)));
5411 -- Indicate that the anonymous access type is created by the
5412 -- array type declaration.
5414 Element_Type := Access_Definition
5416 N => Access_Definition (Component_Def));
5417 Set_Is_Local_Anonymous_Access (Element_Type);
5419 -- Propagate the parent. This field is needed if we have to generate
5420 -- the master_id associated with an anonymous access to task type
5421 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
5423 Set_Parent (Element_Type, Parent (T));
5425 -- Ada 2005 (AI-230): In case of components that are anonymous access
5426 -- types the level of accessibility depends on the enclosing type
5429 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
5431 -- Ada 2005 (AI-254)
5434 CD : constant Node_Id :=
5435 Access_To_Subprogram_Definition
5436 (Access_Definition (Component_Def));
5438 if Present (CD) and then Protected_Present (CD) then
5440 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
5445 -- Constrained array case
5448 T := Create_Itype (E_Void, P, Related_Id, 'T');
5451 if Nkind (Def) = N_Constrained_Array_Definition then
5453 -- Establish Implicit_Base as unconstrained base type
5455 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
5457 Set_Etype (Implicit_Base, Implicit_Base);
5458 Set_Scope (Implicit_Base, Current_Scope);
5459 Set_Has_Delayed_Freeze (Implicit_Base);
5460 Set_Default_SSO (Implicit_Base);
5462 -- The constrained array type is a subtype of the unconstrained one
5464 Set_Ekind (T, E_Array_Subtype);
5465 Init_Size_Align (T);
5466 Set_Etype (T, Implicit_Base);
5467 Set_Scope (T, Current_Scope);
5468 Set_Is_Constrained (T, True);
5469 Set_First_Index (T, First (Discrete_Subtype_Definitions (Def)));
5470 Set_Has_Delayed_Freeze (T);
5472 -- Complete setup of implicit base type
5474 Set_First_Index (Implicit_Base, First_Index (T));
5475 Set_Component_Type (Implicit_Base, Element_Type);
5476 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
5477 Set_Has_Protected (Implicit_Base, Has_Protected (Element_Type));
5478 Set_Component_Size (Implicit_Base, Uint_0);
5479 Set_Packed_Array_Impl_Type (Implicit_Base, Empty);
5480 Set_Has_Controlled_Component
5482 Has_Controlled_Component (Element_Type)
5483 or else Is_Controlled (Element_Type));
5484 Set_Finalize_Storage_Only
5485 (Implicit_Base, Finalize_Storage_Only
5488 -- Unconstrained array case
5491 Set_Ekind (T, E_Array_Type);
5492 Init_Size_Align (T);
5494 Set_Scope (T, Current_Scope);
5495 Set_Component_Size (T, Uint_0);
5496 Set_Is_Constrained (T, False);
5497 Set_First_Index (T, First (Subtype_Marks (Def)));
5498 Set_Has_Delayed_Freeze (T, True);
5499 Set_Has_Task (T, Has_Task (Element_Type));
5500 Set_Has_Protected (T, Has_Protected (Element_Type));
5501 Set_Has_Controlled_Component (T, Has_Controlled_Component
5504 Is_Controlled (Element_Type));
5505 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
5507 Set_Default_SSO (T);
5510 -- Common attributes for both cases
5512 Set_Component_Type (Base_Type (T), Element_Type);
5513 Set_Packed_Array_Impl_Type (T, Empty);
5515 if Aliased_Present (Component_Definition (Def)) then
5516 Check_SPARK_05_Restriction
5517 ("aliased is not allowed", Component_Definition (Def));
5518 Set_Has_Aliased_Components (Etype (T));
5521 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
5522 -- array type to ensure that objects of this type are initialized.
5524 if Ada_Version >= Ada_2005 and then Can_Never_Be_Null (Element_Type) then
5525 Set_Can_Never_Be_Null (T);
5527 if Null_Exclusion_Present (Component_Definition (Def))
5529 -- No need to check itypes because in their case this check was
5530 -- done at their point of creation
5532 and then not Is_Itype (Element_Type)
5535 ("`NOT NULL` not allowed (null already excluded)",
5536 Subtype_Indication (Component_Definition (Def)));
5540 Priv := Private_Component (Element_Type);
5542 if Present (Priv) then
5544 -- Check for circular definitions
5546 if Priv = Any_Type then
5547 Set_Component_Type (Etype (T), Any_Type);
5549 -- There is a gap in the visibility of operations on the composite
5550 -- type only if the component type is defined in a different scope.
5552 elsif Scope (Priv) = Current_Scope then
5555 elsif Is_Limited_Type (Priv) then
5556 Set_Is_Limited_Composite (Etype (T));
5557 Set_Is_Limited_Composite (T);
5559 Set_Is_Private_Composite (Etype (T));
5560 Set_Is_Private_Composite (T);
5564 -- A syntax error in the declaration itself may lead to an empty index
5565 -- list, in which case do a minimal patch.
5567 if No (First_Index (T)) then
5568 Error_Msg_N ("missing index definition in array type declaration", T);
5571 Indexes : constant List_Id :=
5572 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
5574 Set_Discrete_Subtype_Definitions (Def, Indexes);
5575 Set_First_Index (T, First (Indexes));
5580 -- Create a concatenation operator for the new type. Internal array
5581 -- types created for packed entities do not need such, they are
5582 -- compatible with the user-defined type.
5584 if Number_Dimensions (T) = 1
5585 and then not Is_Packed_Array_Impl_Type (T)
5587 New_Concatenation_Op (T);
5590 -- In the case of an unconstrained array the parser has already verified
5591 -- that all the indexes are unconstrained but we still need to make sure
5592 -- that the element type is constrained.
5594 if Is_Indefinite_Subtype (Element_Type) then
5596 ("unconstrained element type in array declaration",
5597 Subtype_Indication (Component_Def));
5599 elsif Is_Abstract_Type (Element_Type) then
5601 ("the type of a component cannot be abstract",
5602 Subtype_Indication (Component_Def));
5605 -- There may be an invariant declared for the component type, but
5606 -- the construction of the component invariant checking procedure
5607 -- takes place during expansion.
5608 end Array_Type_Declaration;
5610 ------------------------------------------------------
5611 -- Replace_Anonymous_Access_To_Protected_Subprogram --
5612 ------------------------------------------------------
5614 function Replace_Anonymous_Access_To_Protected_Subprogram
5615 (N : Node_Id) return Entity_Id
5617 Loc : constant Source_Ptr := Sloc (N);
5619 Curr_Scope : constant Scope_Stack_Entry :=
5620 Scope_Stack.Table (Scope_Stack.Last);
5622 Anon : constant Entity_Id := Make_Temporary (Loc, 'S');
5625 -- Access definition in declaration
5628 -- Object definition or formal definition with an access definition
5631 -- Declaration of anonymous access to subprogram type
5634 -- Original specification in access to subprogram
5639 Set_Is_Internal (Anon);
5642 when N_Component_Declaration |
5643 N_Unconstrained_Array_Definition |
5644 N_Constrained_Array_Definition =>
5645 Comp := Component_Definition (N);
5646 Acc := Access_Definition (Comp);
5648 when N_Discriminant_Specification =>
5649 Comp := Discriminant_Type (N);
5652 when N_Parameter_Specification =>
5653 Comp := Parameter_Type (N);
5656 when N_Access_Function_Definition =>
5657 Comp := Result_Definition (N);
5660 when N_Object_Declaration =>
5661 Comp := Object_Definition (N);
5664 when N_Function_Specification =>
5665 Comp := Result_Definition (N);
5669 raise Program_Error;
5672 Spec := Access_To_Subprogram_Definition (Acc);
5675 Make_Full_Type_Declaration (Loc,
5676 Defining_Identifier => Anon,
5677 Type_Definition => Copy_Separate_Tree (Spec));
5679 Mark_Rewrite_Insertion (Decl);
5681 -- In ASIS mode, analyze the profile on the original node, because
5682 -- the separate copy does not provide enough links to recover the
5683 -- original tree. Analysis is limited to type annotations, within
5684 -- a temporary scope that serves as an anonymous subprogram to collect
5685 -- otherwise useless temporaries and itypes.
5689 Typ : constant Entity_Id := Make_Temporary (Loc, 'S');
5692 if Nkind (Spec) = N_Access_Function_Definition then
5693 Set_Ekind (Typ, E_Function);
5695 Set_Ekind (Typ, E_Procedure);
5698 Set_Parent (Typ, N);
5699 Set_Scope (Typ, Current_Scope);
5702 Process_Formals (Parameter_Specifications (Spec), Spec);
5704 if Nkind (Spec) = N_Access_Function_Definition then
5706 Def : constant Node_Id := Result_Definition (Spec);
5709 -- The result might itself be an anonymous access type, so
5712 if Nkind (Def) = N_Access_Definition then
5713 if Present (Access_To_Subprogram_Definition (Def)) then
5716 Replace_Anonymous_Access_To_Protected_Subprogram
5719 Find_Type (Subtype_Mark (Def));
5732 -- Insert the new declaration in the nearest enclosing scope. If the
5733 -- node is a body and N is its return type, the declaration belongs in
5734 -- the enclosing scope.
5738 if Nkind (P) = N_Subprogram_Body
5739 and then Nkind (N) = N_Function_Specification
5744 while Present (P) and then not Has_Declarations (P) loop
5748 pragma Assert (Present (P));
5750 if Nkind (P) = N_Package_Specification then
5751 Prepend (Decl, Visible_Declarations (P));
5753 Prepend (Decl, Declarations (P));
5756 -- Replace the anonymous type with an occurrence of the new declaration.
5757 -- In all cases the rewritten node does not have the null-exclusion
5758 -- attribute because (if present) it was already inherited by the
5759 -- anonymous entity (Anon). Thus, in case of components we do not
5760 -- inherit this attribute.
5762 if Nkind (N) = N_Parameter_Specification then
5763 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5764 Set_Etype (Defining_Identifier (N), Anon);
5765 Set_Null_Exclusion_Present (N, False);
5767 elsif Nkind (N) = N_Object_Declaration then
5768 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5769 Set_Etype (Defining_Identifier (N), Anon);
5771 elsif Nkind (N) = N_Access_Function_Definition then
5772 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5774 elsif Nkind (N) = N_Function_Specification then
5775 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
5776 Set_Etype (Defining_Unit_Name (N), Anon);
5780 Make_Component_Definition (Loc,
5781 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
5784 Mark_Rewrite_Insertion (Comp);
5786 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition) then
5790 -- Temporarily remove the current scope (record or subprogram) from
5791 -- the stack to add the new declarations to the enclosing scope.
5793 Scope_Stack.Decrement_Last;
5795 Set_Is_Itype (Anon);
5796 Scope_Stack.Append (Curr_Scope);
5799 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
5800 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
5802 end Replace_Anonymous_Access_To_Protected_Subprogram;
5804 -------------------------------
5805 -- Build_Derived_Access_Type --
5806 -------------------------------
5808 procedure Build_Derived_Access_Type
5810 Parent_Type : Entity_Id;
5811 Derived_Type : Entity_Id)
5813 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
5815 Desig_Type : Entity_Id;
5817 Discr_Con_Elist : Elist_Id;
5818 Discr_Con_El : Elmt_Id;
5822 -- Set the designated type so it is available in case this is an access
5823 -- to a self-referential type, e.g. a standard list type with a next
5824 -- pointer. Will be reset after subtype is built.
5826 Set_Directly_Designated_Type
5827 (Derived_Type, Designated_Type (Parent_Type));
5829 Subt := Process_Subtype (S, N);
5831 if Nkind (S) /= N_Subtype_Indication
5832 and then Subt /= Base_Type (Subt)
5834 Set_Ekind (Derived_Type, E_Access_Subtype);
5837 if Ekind (Derived_Type) = E_Access_Subtype then
5839 Pbase : constant Entity_Id := Base_Type (Parent_Type);
5840 Ibase : constant Entity_Id :=
5841 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
5842 Svg_Chars : constant Name_Id := Chars (Ibase);
5843 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
5846 Copy_Node (Pbase, Ibase);
5848 Set_Chars (Ibase, Svg_Chars);
5849 Set_Next_Entity (Ibase, Svg_Next_E);
5850 Set_Sloc (Ibase, Sloc (Derived_Type));
5851 Set_Scope (Ibase, Scope (Derived_Type));
5852 Set_Freeze_Node (Ibase, Empty);
5853 Set_Is_Frozen (Ibase, False);
5854 Set_Comes_From_Source (Ibase, False);
5855 Set_Is_First_Subtype (Ibase, False);
5857 Set_Etype (Ibase, Pbase);
5858 Set_Etype (Derived_Type, Ibase);
5862 Set_Directly_Designated_Type
5863 (Derived_Type, Designated_Type (Subt));
5865 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
5866 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
5867 Set_Size_Info (Derived_Type, Parent_Type);
5868 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
5869 Set_Depends_On_Private (Derived_Type,
5870 Has_Private_Component (Derived_Type));
5871 Conditional_Delay (Derived_Type, Subt);
5873 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
5874 -- that it is not redundant.
5876 if Null_Exclusion_Present (Type_Definition (N)) then
5877 Set_Can_Never_Be_Null (Derived_Type);
5879 -- What is with the "AND THEN FALSE" here ???
5881 if Can_Never_Be_Null (Parent_Type)
5885 ("`NOT NULL` not allowed (& already excludes null)",
5889 elsif Can_Never_Be_Null (Parent_Type) then
5890 Set_Can_Never_Be_Null (Derived_Type);
5893 -- Note: we do not copy the Storage_Size_Variable, since we always go to
5894 -- the root type for this information.
5896 -- Apply range checks to discriminants for derived record case
5897 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
5899 Desig_Type := Designated_Type (Derived_Type);
5900 if Is_Composite_Type (Desig_Type)
5901 and then (not Is_Array_Type (Desig_Type))
5902 and then Has_Discriminants (Desig_Type)
5903 and then Base_Type (Desig_Type) /= Desig_Type
5905 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
5906 Discr_Con_El := First_Elmt (Discr_Con_Elist);
5908 Discr := First_Discriminant (Base_Type (Desig_Type));
5909 while Present (Discr_Con_El) loop
5910 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
5911 Next_Elmt (Discr_Con_El);
5912 Next_Discriminant (Discr);
5915 end Build_Derived_Access_Type;
5917 ------------------------------
5918 -- Build_Derived_Array_Type --
5919 ------------------------------
5921 procedure Build_Derived_Array_Type
5923 Parent_Type : Entity_Id;
5924 Derived_Type : Entity_Id)
5926 Loc : constant Source_Ptr := Sloc (N);
5927 Tdef : constant Node_Id := Type_Definition (N);
5928 Indic : constant Node_Id := Subtype_Indication (Tdef);
5929 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5930 Implicit_Base : Entity_Id;
5931 New_Indic : Node_Id;
5933 procedure Make_Implicit_Base;
5934 -- If the parent subtype is constrained, the derived type is a subtype
5935 -- of an implicit base type derived from the parent base.
5937 ------------------------
5938 -- Make_Implicit_Base --
5939 ------------------------
5941 procedure Make_Implicit_Base is
5944 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5946 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5947 Set_Etype (Implicit_Base, Parent_Base);
5949 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
5950 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
5952 Set_Has_Delayed_Freeze (Implicit_Base, True);
5953 end Make_Implicit_Base;
5955 -- Start of processing for Build_Derived_Array_Type
5958 if not Is_Constrained (Parent_Type) then
5959 if Nkind (Indic) /= N_Subtype_Indication then
5960 Set_Ekind (Derived_Type, E_Array_Type);
5962 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5963 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
5965 Set_Has_Delayed_Freeze (Derived_Type, True);
5969 Set_Etype (Derived_Type, Implicit_Base);
5972 Make_Subtype_Declaration (Loc,
5973 Defining_Identifier => Derived_Type,
5974 Subtype_Indication =>
5975 Make_Subtype_Indication (Loc,
5976 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
5977 Constraint => Constraint (Indic)));
5979 Rewrite (N, New_Indic);
5984 if Nkind (Indic) /= N_Subtype_Indication then
5987 Set_Ekind (Derived_Type, Ekind (Parent_Type));
5988 Set_Etype (Derived_Type, Implicit_Base);
5989 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
5992 Error_Msg_N ("illegal constraint on constrained type", Indic);
5996 -- If parent type is not a derived type itself, and is declared in
5997 -- closed scope (e.g. a subprogram), then we must explicitly introduce
5998 -- the new type's concatenation operator since Derive_Subprograms
5999 -- will not inherit the parent's operator. If the parent type is
6000 -- unconstrained, the operator is of the unconstrained base type.
6002 if Number_Dimensions (Parent_Type) = 1
6003 and then not Is_Limited_Type (Parent_Type)
6004 and then not Is_Derived_Type (Parent_Type)
6005 and then not Is_Package_Or_Generic_Package
6006 (Scope (Base_Type (Parent_Type)))
6008 if not Is_Constrained (Parent_Type)
6009 and then Is_Constrained (Derived_Type)
6011 New_Concatenation_Op (Implicit_Base);
6013 New_Concatenation_Op (Derived_Type);
6016 end Build_Derived_Array_Type;
6018 -----------------------------------
6019 -- Build_Derived_Concurrent_Type --
6020 -----------------------------------
6022 procedure Build_Derived_Concurrent_Type
6024 Parent_Type : Entity_Id;
6025 Derived_Type : Entity_Id)
6027 Loc : constant Source_Ptr := Sloc (N);
6029 Corr_Record : constant Entity_Id := Make_Temporary (Loc, 'C');
6030 Corr_Decl : Node_Id;
6031 Corr_Decl_Needed : Boolean;
6032 -- If the derived type has fewer discriminants than its parent, the
6033 -- corresponding record is also a derived type, in order to account for
6034 -- the bound discriminants. We create a full type declaration for it in
6037 Constraint_Present : constant Boolean :=
6038 Nkind (Subtype_Indication (Type_Definition (N))) =
6039 N_Subtype_Indication;
6041 D_Constraint : Node_Id;
6042 New_Constraint : Elist_Id;
6043 Old_Disc : Entity_Id;
6044 New_Disc : Entity_Id;
6048 Set_Stored_Constraint (Derived_Type, No_Elist);
6049 Corr_Decl_Needed := False;
6052 if Present (Discriminant_Specifications (N))
6053 and then Constraint_Present
6055 Old_Disc := First_Discriminant (Parent_Type);
6056 New_Disc := First (Discriminant_Specifications (N));
6057 while Present (New_Disc) and then Present (Old_Disc) loop
6058 Next_Discriminant (Old_Disc);
6063 if Present (Old_Disc) and then Expander_Active then
6065 -- The new type has fewer discriminants, so we need to create a new
6066 -- corresponding record, which is derived from the corresponding
6067 -- record of the parent, and has a stored constraint that captures
6068 -- the values of the discriminant constraints. The corresponding
6069 -- record is needed only if expander is active and code generation is
6072 -- The type declaration for the derived corresponding record has the
6073 -- same discriminant part and constraints as the current declaration.
6074 -- Copy the unanalyzed tree to build declaration.
6076 Corr_Decl_Needed := True;
6077 New_N := Copy_Separate_Tree (N);
6080 Make_Full_Type_Declaration (Loc,
6081 Defining_Identifier => Corr_Record,
6082 Discriminant_Specifications =>
6083 Discriminant_Specifications (New_N),
6085 Make_Derived_Type_Definition (Loc,
6086 Subtype_Indication =>
6087 Make_Subtype_Indication (Loc,
6090 (Corresponding_Record_Type (Parent_Type), Loc),
6093 (Subtype_Indication (Type_Definition (New_N))))));
6096 -- Copy Storage_Size and Relative_Deadline variables if task case
6098 if Is_Task_Type (Parent_Type) then
6099 Set_Storage_Size_Variable (Derived_Type,
6100 Storage_Size_Variable (Parent_Type));
6101 Set_Relative_Deadline_Variable (Derived_Type,
6102 Relative_Deadline_Variable (Parent_Type));
6105 if Present (Discriminant_Specifications (N)) then
6106 Push_Scope (Derived_Type);
6107 Check_Or_Process_Discriminants (N, Derived_Type);
6109 if Constraint_Present then
6111 Expand_To_Stored_Constraint
6113 Build_Discriminant_Constraints
6115 Subtype_Indication (Type_Definition (N)), True));
6120 elsif Constraint_Present then
6122 -- Build constrained subtype, copying the constraint, and derive
6123 -- from it to create a derived constrained type.
6126 Loc : constant Source_Ptr := Sloc (N);
6127 Anon : constant Entity_Id :=
6128 Make_Defining_Identifier (Loc,
6129 Chars => New_External_Name (Chars (Derived_Type), 'T'));
6134 Make_Subtype_Declaration (Loc,
6135 Defining_Identifier => Anon,
6136 Subtype_Indication =>
6137 New_Copy_Tree (Subtype_Indication (Type_Definition (N))));
6138 Insert_Before (N, Decl);
6141 Rewrite (Subtype_Indication (Type_Definition (N)),
6142 New_Occurrence_Of (Anon, Loc));
6143 Set_Analyzed (Derived_Type, False);
6149 -- By default, operations and private data are inherited from parent.
6150 -- However, in the presence of bound discriminants, a new corresponding
6151 -- record will be created, see below.
6153 Set_Has_Discriminants
6154 (Derived_Type, Has_Discriminants (Parent_Type));
6155 Set_Corresponding_Record_Type
6156 (Derived_Type, Corresponding_Record_Type (Parent_Type));
6158 -- Is_Constrained is set according the parent subtype, but is set to
6159 -- False if the derived type is declared with new discriminants.
6163 (Is_Constrained (Parent_Type) or else Constraint_Present)
6164 and then not Present (Discriminant_Specifications (N)));
6166 if Constraint_Present then
6167 if not Has_Discriminants (Parent_Type) then
6168 Error_Msg_N ("untagged parent must have discriminants", N);
6170 elsif Present (Discriminant_Specifications (N)) then
6172 -- Verify that new discriminants are used to constrain old ones
6177 (Constraint (Subtype_Indication (Type_Definition (N)))));
6179 Old_Disc := First_Discriminant (Parent_Type);
6181 while Present (D_Constraint) loop
6182 if Nkind (D_Constraint) /= N_Discriminant_Association then
6184 -- Positional constraint. If it is a reference to a new
6185 -- discriminant, it constrains the corresponding old one.
6187 if Nkind (D_Constraint) = N_Identifier then
6188 New_Disc := First_Discriminant (Derived_Type);
6189 while Present (New_Disc) loop
6190 exit when Chars (New_Disc) = Chars (D_Constraint);
6191 Next_Discriminant (New_Disc);
6194 if Present (New_Disc) then
6195 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
6199 Next_Discriminant (Old_Disc);
6201 -- if this is a named constraint, search by name for the old
6202 -- discriminants constrained by the new one.
6204 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
6206 -- Find new discriminant with that name
6208 New_Disc := First_Discriminant (Derived_Type);
6209 while Present (New_Disc) loop
6211 Chars (New_Disc) = Chars (Expression (D_Constraint));
6212 Next_Discriminant (New_Disc);
6215 if Present (New_Disc) then
6217 -- Verify that new discriminant renames some discriminant
6218 -- of the parent type, and associate the new discriminant
6219 -- with one or more old ones that it renames.
6225 Selector := First (Selector_Names (D_Constraint));
6226 while Present (Selector) loop
6227 Old_Disc := First_Discriminant (Parent_Type);
6228 while Present (Old_Disc) loop
6229 exit when Chars (Old_Disc) = Chars (Selector);
6230 Next_Discriminant (Old_Disc);
6233 if Present (Old_Disc) then
6234 Set_Corresponding_Discriminant
6235 (New_Disc, Old_Disc);
6244 Next (D_Constraint);
6247 New_Disc := First_Discriminant (Derived_Type);
6248 while Present (New_Disc) loop
6249 if No (Corresponding_Discriminant (New_Disc)) then
6251 ("new discriminant& must constrain old one", N, New_Disc);
6254 Subtypes_Statically_Compatible
6256 Etype (Corresponding_Discriminant (New_Disc)))
6259 ("& not statically compatible with parent discriminant",
6263 Next_Discriminant (New_Disc);
6267 elsif Present (Discriminant_Specifications (N)) then
6269 ("missing discriminant constraint in untagged derivation", N);
6272 -- The entity chain of the derived type includes the new discriminants
6273 -- but shares operations with the parent.
6275 if Present (Discriminant_Specifications (N)) then
6276 Old_Disc := First_Discriminant (Parent_Type);
6277 while Present (Old_Disc) loop
6278 if No (Next_Entity (Old_Disc))
6279 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
6282 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
6286 Next_Discriminant (Old_Disc);
6290 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
6291 if Has_Discriminants (Parent_Type) then
6292 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6293 Set_Discriminant_Constraint (
6294 Derived_Type, Discriminant_Constraint (Parent_Type));
6298 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
6300 Set_Has_Completion (Derived_Type);
6302 if Corr_Decl_Needed then
6303 Set_Stored_Constraint (Derived_Type, New_Constraint);
6304 Insert_After (N, Corr_Decl);
6305 Analyze (Corr_Decl);
6306 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
6308 end Build_Derived_Concurrent_Type;
6310 ------------------------------------
6311 -- Build_Derived_Enumeration_Type --
6312 ------------------------------------
6314 procedure Build_Derived_Enumeration_Type
6316 Parent_Type : Entity_Id;
6317 Derived_Type : Entity_Id)
6319 Loc : constant Source_Ptr := Sloc (N);
6320 Def : constant Node_Id := Type_Definition (N);
6321 Indic : constant Node_Id := Subtype_Indication (Def);
6322 Implicit_Base : Entity_Id;
6323 Literal : Entity_Id;
6324 New_Lit : Entity_Id;
6325 Literals_List : List_Id;
6326 Type_Decl : Node_Id;
6328 Rang_Expr : Node_Id;
6331 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
6332 -- not have explicit literals lists we need to process types derived
6333 -- from them specially. This is handled by Derived_Standard_Character.
6334 -- If the parent type is a generic type, there are no literals either,
6335 -- and we construct the same skeletal representation as for the generic
6338 if Is_Standard_Character_Type (Parent_Type) then
6339 Derived_Standard_Character (N, Parent_Type, Derived_Type);
6341 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
6347 if Nkind (Indic) /= N_Subtype_Indication then
6349 Make_Attribute_Reference (Loc,
6350 Attribute_Name => Name_First,
6351 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6352 Set_Etype (Lo, Derived_Type);
6355 Make_Attribute_Reference (Loc,
6356 Attribute_Name => Name_Last,
6357 Prefix => New_Occurrence_Of (Derived_Type, Loc));
6358 Set_Etype (Hi, Derived_Type);
6360 Set_Scalar_Range (Derived_Type,
6366 -- Analyze subtype indication and verify compatibility
6367 -- with parent type.
6369 if Base_Type (Process_Subtype (Indic, N)) /=
6370 Base_Type (Parent_Type)
6373 ("illegal constraint for formal discrete type", N);
6379 -- If a constraint is present, analyze the bounds to catch
6380 -- premature usage of the derived literals.
6382 if Nkind (Indic) = N_Subtype_Indication
6383 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
6385 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
6386 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
6389 -- Introduce an implicit base type for the derived type even if there
6390 -- is no constraint attached to it, since this seems closer to the
6391 -- Ada semantics. Build a full type declaration tree for the derived
6392 -- type using the implicit base type as the defining identifier. The
6393 -- build a subtype declaration tree which applies the constraint (if
6394 -- any) have it replace the derived type declaration.
6396 Literal := First_Literal (Parent_Type);
6397 Literals_List := New_List;
6398 while Present (Literal)
6399 and then Ekind (Literal) = E_Enumeration_Literal
6401 -- Literals of the derived type have the same representation as
6402 -- those of the parent type, but this representation can be
6403 -- overridden by an explicit representation clause. Indicate
6404 -- that there is no explicit representation given yet. These
6405 -- derived literals are implicit operations of the new type,
6406 -- and can be overridden by explicit ones.
6408 if Nkind (Literal) = N_Defining_Character_Literal then
6410 Make_Defining_Character_Literal (Loc, Chars (Literal));
6412 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
6415 Set_Ekind (New_Lit, E_Enumeration_Literal);
6416 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
6417 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
6418 Set_Enumeration_Rep_Expr (New_Lit, Empty);
6419 Set_Alias (New_Lit, Literal);
6420 Set_Is_Known_Valid (New_Lit, True);
6422 Append (New_Lit, Literals_List);
6423 Next_Literal (Literal);
6427 Make_Defining_Identifier (Sloc (Derived_Type),
6428 Chars => New_External_Name (Chars (Derived_Type), 'B'));
6430 -- Indicate the proper nature of the derived type. This must be done
6431 -- before analysis of the literals, to recognize cases when a literal
6432 -- may be hidden by a previous explicit function definition (cf.
6435 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
6436 Set_Etype (Derived_Type, Implicit_Base);
6439 Make_Full_Type_Declaration (Loc,
6440 Defining_Identifier => Implicit_Base,
6441 Discriminant_Specifications => No_List,
6443 Make_Enumeration_Type_Definition (Loc, Literals_List));
6445 Mark_Rewrite_Insertion (Type_Decl);
6446 Insert_Before (N, Type_Decl);
6447 Analyze (Type_Decl);
6449 -- After the implicit base is analyzed its Etype needs to be changed
6450 -- to reflect the fact that it is derived from the parent type which
6451 -- was ignored during analysis. We also set the size at this point.
6453 Set_Etype (Implicit_Base, Parent_Type);
6455 Set_Size_Info (Implicit_Base, Parent_Type);
6456 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
6457 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
6459 -- Copy other flags from parent type
6461 Set_Has_Non_Standard_Rep
6462 (Implicit_Base, Has_Non_Standard_Rep
6464 Set_Has_Pragma_Ordered
6465 (Implicit_Base, Has_Pragma_Ordered
6467 Set_Has_Delayed_Freeze (Implicit_Base);
6469 -- Process the subtype indication including a validation check on the
6470 -- constraint, if any. If a constraint is given, its bounds must be
6471 -- implicitly converted to the new type.
6473 if Nkind (Indic) = N_Subtype_Indication then
6475 R : constant Node_Id :=
6476 Range_Expression (Constraint (Indic));
6479 if Nkind (R) = N_Range then
6480 Hi := Build_Scalar_Bound
6481 (High_Bound (R), Parent_Type, Implicit_Base);
6482 Lo := Build_Scalar_Bound
6483 (Low_Bound (R), Parent_Type, Implicit_Base);
6486 -- Constraint is a Range attribute. Replace with explicit
6487 -- mention of the bounds of the prefix, which must be a
6490 Analyze (Prefix (R));
6492 Convert_To (Implicit_Base,
6493 Make_Attribute_Reference (Loc,
6494 Attribute_Name => Name_Last,
6496 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6499 Convert_To (Implicit_Base,
6500 Make_Attribute_Reference (Loc,
6501 Attribute_Name => Name_First,
6503 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
6510 (Type_High_Bound (Parent_Type),
6511 Parent_Type, Implicit_Base);
6514 (Type_Low_Bound (Parent_Type),
6515 Parent_Type, Implicit_Base);
6523 -- If we constructed a default range for the case where no range
6524 -- was given, then the expressions in the range must not freeze
6525 -- since they do not correspond to expressions in the source.
6527 if Nkind (Indic) /= N_Subtype_Indication then
6528 Set_Must_Not_Freeze (Lo);
6529 Set_Must_Not_Freeze (Hi);
6530 Set_Must_Not_Freeze (Rang_Expr);
6534 Make_Subtype_Declaration (Loc,
6535 Defining_Identifier => Derived_Type,
6536 Subtype_Indication =>
6537 Make_Subtype_Indication (Loc,
6538 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
6540 Make_Range_Constraint (Loc,
6541 Range_Expression => Rang_Expr))));
6545 -- Propagate the aspects from the original type declaration to the
6546 -- declaration of the implicit base.
6548 Move_Aspects (From => Original_Node (N), To => Type_Decl);
6550 -- Apply a range check. Since this range expression doesn't have an
6551 -- Etype, we have to specifically pass the Source_Typ parameter. Is
6554 if Nkind (Indic) = N_Subtype_Indication then
6556 (Range_Expression (Constraint (Indic)), Parent_Type,
6557 Source_Typ => Entity (Subtype_Mark (Indic)));
6560 end Build_Derived_Enumeration_Type;
6562 --------------------------------
6563 -- Build_Derived_Numeric_Type --
6564 --------------------------------
6566 procedure Build_Derived_Numeric_Type
6568 Parent_Type : Entity_Id;
6569 Derived_Type : Entity_Id)
6571 Loc : constant Source_Ptr := Sloc (N);
6572 Tdef : constant Node_Id := Type_Definition (N);
6573 Indic : constant Node_Id := Subtype_Indication (Tdef);
6574 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
6575 No_Constraint : constant Boolean := Nkind (Indic) /=
6576 N_Subtype_Indication;
6577 Implicit_Base : Entity_Id;
6583 -- Process the subtype indication including a validation check on
6584 -- the constraint if any.
6586 Discard_Node (Process_Subtype (Indic, N));
6588 -- Introduce an implicit base type for the derived type even if there
6589 -- is no constraint attached to it, since this seems closer to the Ada
6593 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
6595 Set_Etype (Implicit_Base, Parent_Base);
6596 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
6597 Set_Size_Info (Implicit_Base, Parent_Base);
6598 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
6599 Set_Parent (Implicit_Base, Parent (Derived_Type));
6600 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
6602 -- Set RM Size for discrete type or decimal fixed-point type
6603 -- Ordinary fixed-point is excluded, why???
6605 if Is_Discrete_Type (Parent_Base)
6606 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
6608 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
6611 Set_Has_Delayed_Freeze (Implicit_Base);
6613 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
6614 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
6616 Set_Scalar_Range (Implicit_Base,
6621 if Has_Infinities (Parent_Base) then
6622 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
6625 -- The Derived_Type, which is the entity of the declaration, is a
6626 -- subtype of the implicit base. Its Ekind is a subtype, even in the
6627 -- absence of an explicit constraint.
6629 Set_Etype (Derived_Type, Implicit_Base);
6631 -- If we did not have a constraint, then the Ekind is set from the
6632 -- parent type (otherwise Process_Subtype has set the bounds)
6634 if No_Constraint then
6635 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
6638 -- If we did not have a range constraint, then set the range from the
6639 -- parent type. Otherwise, the Process_Subtype call has set the bounds.
6641 if No_Constraint or else not Has_Range_Constraint (Indic) then
6642 Set_Scalar_Range (Derived_Type,
6644 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
6645 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
6646 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6648 if Has_Infinities (Parent_Type) then
6649 Set_Includes_Infinities (Scalar_Range (Derived_Type));
6652 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
6655 Set_Is_Descendent_Of_Address (Derived_Type,
6656 Is_Descendent_Of_Address (Parent_Type));
6657 Set_Is_Descendent_Of_Address (Implicit_Base,
6658 Is_Descendent_Of_Address (Parent_Type));
6660 -- Set remaining type-specific fields, depending on numeric type
6662 if Is_Modular_Integer_Type (Parent_Type) then
6663 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
6665 Set_Non_Binary_Modulus
6666 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
6669 (Implicit_Base, Is_Known_Valid (Parent_Base));
6671 elsif Is_Floating_Point_Type (Parent_Type) then
6673 -- Digits of base type is always copied from the digits value of
6674 -- the parent base type, but the digits of the derived type will
6675 -- already have been set if there was a constraint present.
6677 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6678 Set_Float_Rep (Implicit_Base, Float_Rep (Parent_Base));
6680 if No_Constraint then
6681 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
6684 elsif Is_Fixed_Point_Type (Parent_Type) then
6686 -- Small of base type and derived type are always copied from the
6687 -- parent base type, since smalls never change. The delta of the
6688 -- base type is also copied from the parent base type. However the
6689 -- delta of the derived type will have been set already if a
6690 -- constraint was present.
6692 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
6693 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
6694 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
6696 if No_Constraint then
6697 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
6700 -- The scale and machine radix in the decimal case are always
6701 -- copied from the parent base type.
6703 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
6704 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
6705 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
6707 Set_Machine_Radix_10
6708 (Derived_Type, Machine_Radix_10 (Parent_Base));
6709 Set_Machine_Radix_10
6710 (Implicit_Base, Machine_Radix_10 (Parent_Base));
6712 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
6714 if No_Constraint then
6715 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
6718 -- the analysis of the subtype_indication sets the
6719 -- digits value of the derived type.
6726 if Is_Integer_Type (Parent_Type) then
6727 Set_Has_Shift_Operator
6728 (Implicit_Base, Has_Shift_Operator (Parent_Type));
6731 -- The type of the bounds is that of the parent type, and they
6732 -- must be converted to the derived type.
6734 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
6736 -- The implicit_base should be frozen when the derived type is frozen,
6737 -- but note that it is used in the conversions of the bounds. For fixed
6738 -- types we delay the determination of the bounds until the proper
6739 -- freezing point. For other numeric types this is rejected by GCC, for
6740 -- reasons that are currently unclear (???), so we choose to freeze the
6741 -- implicit base now. In the case of integers and floating point types
6742 -- this is harmless because subsequent representation clauses cannot
6743 -- affect anything, but it is still baffling that we cannot use the
6744 -- same mechanism for all derived numeric types.
6746 -- There is a further complication: actually some representation
6747 -- clauses can affect the implicit base type. For example, attribute
6748 -- definition clauses for stream-oriented attributes need to set the
6749 -- corresponding TSS entries on the base type, and this normally
6750 -- cannot be done after the base type is frozen, so the circuitry in
6751 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility
6752 -- and not use Set_TSS in this case.
6754 -- There are also consequences for the case of delayed representation
6755 -- aspects for some cases. For example, a Size aspect is delayed and
6756 -- should not be evaluated to the freeze point. This early freezing
6757 -- means that the size attribute evaluation happens too early???
6759 if Is_Fixed_Point_Type (Parent_Type) then
6760 Conditional_Delay (Implicit_Base, Parent_Type);
6762 Freeze_Before (N, Implicit_Base);
6764 end Build_Derived_Numeric_Type;
6766 --------------------------------
6767 -- Build_Derived_Private_Type --
6768 --------------------------------
6770 procedure Build_Derived_Private_Type
6772 Parent_Type : Entity_Id;
6773 Derived_Type : Entity_Id;
6774 Is_Completion : Boolean;
6775 Derive_Subps : Boolean := True)
6777 Loc : constant Source_Ptr := Sloc (N);
6778 Par_Base : constant Entity_Id := Base_Type (Parent_Type);
6779 Par_Scope : constant Entity_Id := Scope (Par_Base);
6780 Full_N : constant Node_Id := New_Copy_Tree (N);
6781 Full_Der : Entity_Id := New_Copy (Derived_Type);
6784 procedure Build_Full_Derivation;
6785 -- Build full derivation, i.e. derive from the full view
6787 procedure Copy_And_Build;
6788 -- Copy derived type declaration, replace parent with its full view,
6789 -- and build derivation
6791 ---------------------------
6792 -- Build_Full_Derivation --
6793 ---------------------------
6795 procedure Build_Full_Derivation is
6797 -- If parent scope is not open, install the declarations
6799 if not In_Open_Scopes (Par_Scope) then
6800 Install_Private_Declarations (Par_Scope);
6801 Install_Visible_Declarations (Par_Scope);
6803 Uninstall_Declarations (Par_Scope);
6805 -- If parent scope is open and in another unit, and parent has a
6806 -- completion, then the derivation is taking place in the visible
6807 -- part of a child unit. In that case retrieve the full view of
6808 -- the parent momentarily.
6810 elsif not In_Same_Source_Unit (N, Parent_Type) then
6811 Full_P := Full_View (Parent_Type);
6812 Exchange_Declarations (Parent_Type);
6814 Exchange_Declarations (Full_P);
6816 -- Otherwise it is a local derivation
6821 end Build_Full_Derivation;
6823 --------------------
6824 -- Copy_And_Build --
6825 --------------------
6827 procedure Copy_And_Build is
6828 Full_Parent : Entity_Id := Parent_Type;
6831 -- If the parent is itself derived from another private type,
6832 -- installing the private declarations has not affected its
6833 -- privacy status, so use its own full view explicitly.
6835 if Is_Private_Type (Full_Parent)
6836 and then Present (Full_View (Full_Parent))
6838 Full_Parent := Full_View (Full_Parent);
6841 -- And its underlying full view if necessary
6843 if Is_Private_Type (Full_Parent)
6844 and then Present (Underlying_Full_View (Full_Parent))
6846 Full_Parent := Underlying_Full_View (Full_Parent);
6849 -- For record, access and most enumeration types, derivation from
6850 -- the full view requires a fully-fledged declaration. In the other
6851 -- cases, just use an itype.
6853 if Ekind (Full_Parent) in Record_Kind
6854 or else Ekind (Full_Parent) in Access_Kind
6856 (Ekind (Full_Parent) in Enumeration_Kind
6857 and then not Is_Standard_Character_Type (Full_Parent)
6858 and then not Is_Generic_Type (Root_Type (Full_Parent)))
6860 -- Copy and adjust declaration to provide a completion for what
6861 -- is originally a private declaration. Indicate that full view
6862 -- is internally generated.
6864 Set_Comes_From_Source (Full_N, False);
6865 Set_Comes_From_Source (Full_Der, False);
6866 Set_Parent (Full_Der, Full_N);
6867 Set_Defining_Identifier (Full_N, Full_Der);
6869 -- If there are no constraints, adjust the subtype mark
6871 if Nkind (Subtype_Indication (Type_Definition (Full_N))) /=
6872 N_Subtype_Indication
6874 Set_Subtype_Indication
6875 (Type_Definition (Full_N),
6876 New_Occurrence_Of (Full_Parent, Sloc (Full_N)));
6879 Insert_After (N, Full_N);
6881 -- Build full view of derived type from full view of parent which
6882 -- is now installed. Subprograms have been derived on the partial
6883 -- view, the completion does not derive them anew.
6885 if Ekind (Full_Parent) in Record_Kind then
6887 -- If parent type is tagged, the completion inherits the proper
6888 -- primitive operations.
6890 if Is_Tagged_Type (Parent_Type) then
6891 Build_Derived_Record_Type
6892 (Full_N, Full_Parent, Full_Der, Derive_Subps);
6894 Build_Derived_Record_Type
6895 (Full_N, Full_Parent, Full_Der, Derive_Subps => False);
6900 (Full_N, Full_Parent, Full_Der,
6901 Is_Completion => False, Derive_Subps => False);
6904 -- The full declaration has been introduced into the tree and
6905 -- processed in the step above. It should not be analyzed again
6906 -- (when encountered later in the current list of declarations)
6907 -- to prevent spurious name conflicts. The full entity remains
6910 Set_Analyzed (Full_N);
6914 Make_Defining_Identifier (Sloc (Derived_Type),
6915 Chars => Chars (Derived_Type));
6916 Set_Is_Itype (Full_Der);
6917 Set_Associated_Node_For_Itype (Full_Der, N);
6918 Set_Parent (Full_Der, N);
6920 (N, Full_Parent, Full_Der,
6921 Is_Completion => False, Derive_Subps => False);
6924 Set_Has_Private_Declaration (Full_Der);
6925 Set_Has_Private_Declaration (Derived_Type);
6927 Set_Scope (Full_Der, Scope (Derived_Type));
6928 Set_Is_First_Subtype (Full_Der, Is_First_Subtype (Derived_Type));
6929 Set_Has_Size_Clause (Full_Der, False);
6930 Set_Has_Alignment_Clause (Full_Der, False);
6931 Set_Has_Delayed_Freeze (Full_Der);
6932 Set_Is_Frozen (Full_Der, False);
6933 Set_Freeze_Node (Full_Der, Empty);
6934 Set_Depends_On_Private (Full_Der, Has_Private_Component (Full_Der));
6935 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
6937 -- The convention on the base type may be set in the private part
6938 -- and not propagated to the subtype until later, so we obtain the
6939 -- convention from the base type of the parent.
6941 Set_Convention (Full_Der, Convention (Base_Type (Full_Parent)));
6944 -- Start of processing for Build_Derived_Private_Type
6947 if Is_Tagged_Type (Parent_Type) then
6948 Full_P := Full_View (Parent_Type);
6950 -- A type extension of a type with unknown discriminants is an
6951 -- indefinite type that the back-end cannot handle directly.
6952 -- We treat it as a private type, and build a completion that is
6953 -- derived from the full view of the parent, and hopefully has
6954 -- known discriminants.
6956 -- If the full view of the parent type has an underlying record view,
6957 -- use it to generate the underlying record view of this derived type
6958 -- (required for chains of derivations with unknown discriminants).
6960 -- Minor optimization: we avoid the generation of useless underlying
6961 -- record view entities if the private type declaration has unknown
6962 -- discriminants but its corresponding full view has no
6965 if Has_Unknown_Discriminants (Parent_Type)
6966 and then Present (Full_P)
6967 and then (Has_Discriminants (Full_P)
6968 or else Present (Underlying_Record_View (Full_P)))
6969 and then not In_Open_Scopes (Par_Scope)
6970 and then Expander_Active
6973 Full_Der : constant Entity_Id := Make_Temporary (Loc, 'T');
6974 New_Ext : constant Node_Id :=
6976 (Record_Extension_Part (Type_Definition (N)));
6980 Build_Derived_Record_Type
6981 (N, Parent_Type, Derived_Type, Derive_Subps);
6983 -- Build anonymous completion, as a derivation from the full
6984 -- view of the parent. This is not a completion in the usual
6985 -- sense, because the current type is not private.
6988 Make_Full_Type_Declaration (Loc,
6989 Defining_Identifier => Full_Der,
6991 Make_Derived_Type_Definition (Loc,
6992 Subtype_Indication =>
6994 (Subtype_Indication (Type_Definition (N))),
6995 Record_Extension_Part => New_Ext));
6997 -- If the parent type has an underlying record view, use it
6998 -- here to build the new underlying record view.
7000 if Present (Underlying_Record_View (Full_P)) then
7002 (Nkind (Subtype_Indication (Type_Definition (Decl)))
7004 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
7005 Underlying_Record_View (Full_P));
7008 Install_Private_Declarations (Par_Scope);
7009 Install_Visible_Declarations (Par_Scope);
7010 Insert_Before (N, Decl);
7012 -- Mark entity as an underlying record view before analysis,
7013 -- to avoid generating the list of its primitive operations
7014 -- (which is not really required for this entity) and thus
7015 -- prevent spurious errors associated with missing overriding
7016 -- of abstract primitives (overridden only for Derived_Type).
7018 Set_Ekind (Full_Der, E_Record_Type);
7019 Set_Is_Underlying_Record_View (Full_Der);
7020 Set_Default_SSO (Full_Der);
7024 pragma Assert (Has_Discriminants (Full_Der)
7025 and then not Has_Unknown_Discriminants (Full_Der));
7027 Uninstall_Declarations (Par_Scope);
7029 -- Freeze the underlying record view, to prevent generation of
7030 -- useless dispatching information, which is simply shared with
7031 -- the real derived type.
7033 Set_Is_Frozen (Full_Der);
7035 -- If the derived type has access discriminants, create
7036 -- references to their anonymous types now, to prevent
7037 -- back-end problems when their first use is in generated
7038 -- bodies of primitives.
7044 E := First_Entity (Full_Der);
7046 while Present (E) loop
7047 if Ekind (E) = E_Discriminant
7048 and then Ekind (Etype (E)) = E_Anonymous_Access_Type
7050 Build_Itype_Reference (Etype (E), Decl);
7057 -- Set up links between real entity and underlying record view
7059 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
7060 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
7063 -- If discriminants are known, build derived record
7066 Build_Derived_Record_Type
7067 (N, Parent_Type, Derived_Type, Derive_Subps);
7072 elsif Has_Discriminants (Parent_Type) then
7074 -- Build partial view of derived type from partial view of parent.
7075 -- This must be done before building the full derivation because the
7076 -- second derivation will modify the discriminants of the first and
7077 -- the discriminants are chained with the rest of the components in
7078 -- the full derivation.
7080 Build_Derived_Record_Type
7081 (N, Parent_Type, Derived_Type, Derive_Subps);
7083 -- Build the full derivation if this is not the anonymous derived
7084 -- base type created by Build_Derived_Record_Type in the constrained
7085 -- case (see point 5. of its head comment) since we build it for the
7086 -- derived subtype. And skip it for protected types altogether, as
7087 -- gigi does not use these types directly.
7089 if Present (Full_View (Parent_Type))
7090 and then not Is_Itype (Derived_Type)
7091 and then not (Ekind (Full_View (Parent_Type)) in Protected_Kind)
7094 Der_Base : constant Entity_Id := Base_Type (Derived_Type);
7096 Last_Discr : Entity_Id;
7099 -- If this is not a completion, construct the implicit full
7100 -- view by deriving from the full view of the parent type.
7101 -- But if this is a completion, the derived private type
7102 -- being built is a full view and the full derivation can
7103 -- only be its underlying full view.
7105 Build_Full_Derivation;
7107 if not Is_Completion then
7108 Set_Full_View (Derived_Type, Full_Der);
7110 Set_Underlying_Full_View (Derived_Type, Full_Der);
7113 if not Is_Base_Type (Derived_Type) then
7114 Set_Full_View (Der_Base, Base_Type (Full_Der));
7117 -- Copy the discriminant list from full view to the partial
7118 -- view (base type and its subtype). Gigi requires that the
7119 -- partial and full views have the same discriminants.
7121 -- Note that since the partial view points to discriminants
7122 -- in the full view, their scope will be that of the full
7123 -- view. This might cause some front end problems and need
7126 Discr := First_Discriminant (Base_Type (Full_Der));
7127 Set_First_Entity (Der_Base, Discr);
7130 Last_Discr := Discr;
7131 Next_Discriminant (Discr);
7132 exit when No (Discr);
7135 Set_Last_Entity (Der_Base, Last_Discr);
7136 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
7137 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
7139 Set_Stored_Constraint
7140 (Full_Der, Stored_Constraint (Derived_Type));
7144 elsif Present (Full_View (Parent_Type))
7145 and then Has_Discriminants (Full_View (Parent_Type))
7147 if Has_Unknown_Discriminants (Parent_Type)
7148 and then Nkind (Subtype_Indication (Type_Definition (N))) =
7149 N_Subtype_Indication
7152 ("cannot constrain type with unknown discriminants",
7153 Subtype_Indication (Type_Definition (N)));
7157 -- If this is not a completion, construct the implicit full view by
7158 -- deriving from the full view of the parent type. But if this is a
7159 -- completion, the derived private type being built is a full view
7160 -- and the full derivation can only be its underlying full view.
7162 Build_Full_Derivation;
7164 if not Is_Completion then
7165 Set_Full_View (Derived_Type, Full_Der);
7167 Set_Underlying_Full_View (Derived_Type, Full_Der);
7170 -- In any case, the primitive operations are inherited from the
7171 -- parent type, not from the internal full view.
7173 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
7175 if Derive_Subps then
7176 Derive_Subprograms (Parent_Type, Derived_Type);
7179 Set_Stored_Constraint (Derived_Type, No_Elist);
7181 (Derived_Type, Is_Constrained (Full_View (Parent_Type)));
7184 -- Untagged type, No discriminants on either view
7186 if Nkind (Subtype_Indication (Type_Definition (N))) =
7187 N_Subtype_Indication
7190 ("illegal constraint on type without discriminants", N);
7193 if Present (Discriminant_Specifications (N))
7194 and then Present (Full_View (Parent_Type))
7195 and then not Is_Tagged_Type (Full_View (Parent_Type))
7197 Error_Msg_N ("cannot add discriminants to untagged type", N);
7200 Set_Stored_Constraint (Derived_Type, No_Elist);
7201 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
7202 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7203 Set_Has_Controlled_Component
7204 (Derived_Type, Has_Controlled_Component
7207 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7209 if not Is_Controlled (Parent_Type) then
7210 Set_Finalize_Storage_Only
7211 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
7214 -- If this is not a completion, construct the implicit full view by
7215 -- deriving from the full view of the parent type.
7217 -- ??? If the parent is untagged private and its completion is
7218 -- tagged, this mechanism will not work because we cannot derive from
7219 -- the tagged full view unless we have an extension.
7221 if Present (Full_View (Parent_Type))
7222 and then not Is_Tagged_Type (Full_View (Parent_Type))
7223 and then not Is_Completion
7225 Build_Full_Derivation;
7226 Set_Full_View (Derived_Type, Full_Der);
7230 Set_Has_Unknown_Discriminants (Derived_Type,
7231 Has_Unknown_Discriminants (Parent_Type));
7233 if Is_Private_Type (Derived_Type) then
7234 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7237 -- If the parent base type is in scope, add the derived type to its
7238 -- list of private dependents, because its full view may become
7239 -- visible subsequently (in a nested private part, a body, or in a
7240 -- further child unit).
7242 if Is_Private_Type (Par_Base) and then In_Open_Scopes (Par_Scope) then
7243 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
7245 -- Check for unusual case where a type completed by a private
7246 -- derivation occurs within a package nested in a child unit, and
7247 -- the parent is declared in an ancestor.
7249 if Is_Child_Unit (Scope (Current_Scope))
7250 and then Is_Completion
7251 and then In_Private_Part (Current_Scope)
7252 and then Scope (Parent_Type) /= Current_Scope
7254 -- Note that if the parent has a completion in the private part,
7255 -- (which is itself a derivation from some other private type)
7256 -- it is that completion that is visible, there is no full view
7257 -- available, and no special processing is needed.
7259 and then Present (Full_View (Parent_Type))
7261 -- In this case, the full view of the parent type will become
7262 -- visible in the body of the enclosing child, and only then will
7263 -- the current type be possibly non-private. Build an underlying
7264 -- full view that will be installed when the enclosing child body
7267 if Present (Underlying_Full_View (Derived_Type)) then
7268 Full_Der := Underlying_Full_View (Derived_Type);
7270 Build_Full_Derivation;
7271 Set_Underlying_Full_View (Derived_Type, Full_Der);
7274 -- The full view will be used to swap entities on entry/exit to
7275 -- the body, and must appear in the entity list for the package.
7277 Append_Entity (Full_Der, Scope (Derived_Type));
7280 end Build_Derived_Private_Type;
7282 -------------------------------
7283 -- Build_Derived_Record_Type --
7284 -------------------------------
7288 -- Ideally we would like to use the same model of type derivation for
7289 -- tagged and untagged record types. Unfortunately this is not quite
7290 -- possible because the semantics of representation clauses is different
7291 -- for tagged and untagged records under inheritance. Consider the
7294 -- type R (...) is [tagged] record ... end record;
7295 -- type T (...) is new R (...) [with ...];
7297 -- The representation clauses for T can specify a completely different
7298 -- record layout from R's. Hence the same component can be placed in two
7299 -- very different positions in objects of type T and R. If R and T are
7300 -- tagged types, representation clauses for T can only specify the layout
7301 -- of non inherited components, thus components that are common in R and T
7302 -- have the same position in objects of type R and T.
7304 -- This has two implications. The first is that the entire tree for R's
7305 -- declaration needs to be copied for T in the untagged case, so that T
7306 -- can be viewed as a record type of its own with its own representation
7307 -- clauses. The second implication is the way we handle discriminants.
7308 -- Specifically, in the untagged case we need a way to communicate to Gigi
7309 -- what are the real discriminants in the record, while for the semantics
7310 -- we need to consider those introduced by the user to rename the
7311 -- discriminants in the parent type. This is handled by introducing the
7312 -- notion of stored discriminants. See below for more.
7314 -- Fortunately the way regular components are inherited can be handled in
7315 -- the same way in tagged and untagged types.
7317 -- To complicate things a bit more the private view of a private extension
7318 -- cannot be handled in the same way as the full view (for one thing the
7319 -- semantic rules are somewhat different). We will explain what differs
7322 -- 2. DISCRIMINANTS UNDER INHERITANCE
7324 -- The semantic rules governing the discriminants of derived types are
7327 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
7328 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
7330 -- If parent type has discriminants, then the discriminants that are
7331 -- declared in the derived type are [3.4 (11)]:
7333 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
7336 -- o Otherwise, each discriminant of the parent type (implicitly declared
7337 -- in the same order with the same specifications). In this case, the
7338 -- discriminants are said to be "inherited", or if unknown in the parent
7339 -- are also unknown in the derived type.
7341 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
7343 -- o The parent subtype must be constrained;
7345 -- o If the parent type is not a tagged type, then each discriminant of
7346 -- the derived type must be used in the constraint defining a parent
7347 -- subtype. [Implementation note: This ensures that the new discriminant
7348 -- can share storage with an existing discriminant.]
7350 -- For the derived type each discriminant of the parent type is either
7351 -- inherited, constrained to equal some new discriminant of the derived
7352 -- type, or constrained to the value of an expression.
7354 -- When inherited or constrained to equal some new discriminant, the
7355 -- parent discriminant and the discriminant of the derived type are said
7358 -- If a discriminant of the parent type is constrained to a specific value
7359 -- in the derived type definition, then the discriminant is said to be
7360 -- "specified" by that derived type definition.
7362 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
7364 -- We have spoken about stored discriminants in point 1 (introduction)
7365 -- above. There are two sort of stored discriminants: implicit and
7366 -- explicit. As long as the derived type inherits the same discriminants as
7367 -- the root record type, stored discriminants are the same as regular
7368 -- discriminants, and are said to be implicit. However, if any discriminant
7369 -- in the root type was renamed in the derived type, then the derived
7370 -- type will contain explicit stored discriminants. Explicit stored
7371 -- discriminants are discriminants in addition to the semantically visible
7372 -- discriminants defined for the derived type. Stored discriminants are
7373 -- used by Gigi to figure out what are the physical discriminants in
7374 -- objects of the derived type (see precise definition in einfo.ads).
7375 -- As an example, consider the following:
7377 -- type R (D1, D2, D3 : Int) is record ... end record;
7378 -- type T1 is new R;
7379 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
7380 -- type T3 is new T2;
7381 -- type T4 (Y : Int) is new T3 (Y, 99);
7383 -- The following table summarizes the discriminants and stored
7384 -- discriminants in R and T1 through T4.
7386 -- Type Discrim Stored Discrim Comment
7387 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
7388 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
7389 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
7390 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
7391 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
7393 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
7394 -- find the corresponding discriminant in the parent type, while
7395 -- Original_Record_Component (abbreviated ORC below), the actual physical
7396 -- component that is renamed. Finally the field Is_Completely_Hidden
7397 -- (abbreviated ICH below) is set for all explicit stored discriminants
7398 -- (see einfo.ads for more info). For the above example this gives:
7400 -- Discrim CD ORC ICH
7401 -- ^^^^^^^ ^^ ^^^ ^^^
7402 -- D1 in R empty itself no
7403 -- D2 in R empty itself no
7404 -- D3 in R empty itself no
7406 -- D1 in T1 D1 in R itself no
7407 -- D2 in T1 D2 in R itself no
7408 -- D3 in T1 D3 in R itself no
7410 -- X1 in T2 D3 in T1 D3 in T2 no
7411 -- X2 in T2 D1 in T1 D1 in T2 no
7412 -- D1 in T2 empty itself yes
7413 -- D2 in T2 empty itself yes
7414 -- D3 in T2 empty itself yes
7416 -- X1 in T3 X1 in T2 D3 in T3 no
7417 -- X2 in T3 X2 in T2 D1 in T3 no
7418 -- D1 in T3 empty itself yes
7419 -- D2 in T3 empty itself yes
7420 -- D3 in T3 empty itself yes
7422 -- Y in T4 X1 in T3 D3 in T3 no
7423 -- D1 in T3 empty itself yes
7424 -- D2 in T3 empty itself yes
7425 -- D3 in T3 empty itself yes
7427 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
7429 -- Type derivation for tagged types is fairly straightforward. If no
7430 -- discriminants are specified by the derived type, these are inherited
7431 -- from the parent. No explicit stored discriminants are ever necessary.
7432 -- The only manipulation that is done to the tree is that of adding a
7433 -- _parent field with parent type and constrained to the same constraint
7434 -- specified for the parent in the derived type definition. For instance:
7436 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
7437 -- type T1 is new R with null record;
7438 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
7440 -- are changed into:
7442 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
7443 -- _parent : R (D1, D2, D3);
7446 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
7447 -- _parent : T1 (X2, 88, X1);
7450 -- The discriminants actually present in R, T1 and T2 as well as their CD,
7451 -- ORC and ICH fields are:
7453 -- Discrim CD ORC ICH
7454 -- ^^^^^^^ ^^ ^^^ ^^^
7455 -- D1 in R empty itself no
7456 -- D2 in R empty itself no
7457 -- D3 in R empty itself no
7459 -- D1 in T1 D1 in R D1 in R no
7460 -- D2 in T1 D2 in R D2 in R no
7461 -- D3 in T1 D3 in R D3 in R no
7463 -- X1 in T2 D3 in T1 D3 in R no
7464 -- X2 in T2 D1 in T1 D1 in R no
7466 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
7468 -- Regardless of whether we dealing with a tagged or untagged type
7469 -- we will transform all derived type declarations of the form
7471 -- type T is new R (...) [with ...];
7473 -- subtype S is R (...);
7474 -- type T is new S [with ...];
7476 -- type BT is new R [with ...];
7477 -- subtype T is BT (...);
7479 -- That is, the base derived type is constrained only if it has no
7480 -- discriminants. The reason for doing this is that GNAT's semantic model
7481 -- assumes that a base type with discriminants is unconstrained.
7483 -- Note that, strictly speaking, the above transformation is not always
7484 -- correct. Consider for instance the following excerpt from ACVC b34011a:
7486 -- procedure B34011A is
7487 -- type REC (D : integer := 0) is record
7492 -- type T6 is new Rec;
7493 -- function F return T6;
7498 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
7501 -- The definition of Q6.U is illegal. However transforming Q6.U into
7503 -- type BaseU is new T6;
7504 -- subtype U is BaseU (Q6.F.I)
7506 -- turns U into a legal subtype, which is incorrect. To avoid this problem
7507 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
7508 -- the transformation described above.
7510 -- There is another instance where the above transformation is incorrect.
7514 -- type Base (D : Integer) is tagged null record;
7515 -- procedure P (X : Base);
7517 -- type Der is new Base (2) with null record;
7518 -- procedure P (X : Der);
7521 -- Then the above transformation turns this into
7523 -- type Der_Base is new Base with null record;
7524 -- -- procedure P (X : Base) is implicitly inherited here
7525 -- -- as procedure P (X : Der_Base).
7527 -- subtype Der is Der_Base (2);
7528 -- procedure P (X : Der);
7529 -- -- The overriding of P (X : Der_Base) is illegal since we
7530 -- -- have a parameter conformance problem.
7532 -- To get around this problem, after having semantically processed Der_Base
7533 -- and the rewritten subtype declaration for Der, we copy Der_Base field
7534 -- Discriminant_Constraint from Der so that when parameter conformance is
7535 -- checked when P is overridden, no semantic errors are flagged.
7537 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
7539 -- Regardless of whether we are dealing with a tagged or untagged type
7540 -- we will transform all derived type declarations of the form
7542 -- type R (D1, .., Dn : ...) is [tagged] record ...;
7543 -- type T is new R [with ...];
7545 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
7547 -- The reason for such transformation is that it allows us to implement a
7548 -- very clean form of component inheritance as explained below.
7550 -- Note that this transformation is not achieved by direct tree rewriting
7551 -- and manipulation, but rather by redoing the semantic actions that the
7552 -- above transformation will entail. This is done directly in routine
7553 -- Inherit_Components.
7555 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
7557 -- In both tagged and untagged derived types, regular non discriminant
7558 -- components are inherited in the derived type from the parent type. In
7559 -- the absence of discriminants component, inheritance is straightforward
7560 -- as components can simply be copied from the parent.
7562 -- If the parent has discriminants, inheriting components constrained with
7563 -- these discriminants requires caution. Consider the following example:
7565 -- type R (D1, D2 : Positive) is [tagged] record
7566 -- S : String (D1 .. D2);
7569 -- type T1 is new R [with null record];
7570 -- type T2 (X : positive) is new R (1, X) [with null record];
7572 -- As explained in 6. above, T1 is rewritten as
7573 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
7574 -- which makes the treatment for T1 and T2 identical.
7576 -- What we want when inheriting S, is that references to D1 and D2 in R are
7577 -- replaced with references to their correct constraints, i.e. D1 and D2 in
7578 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
7579 -- with either discriminant references in the derived type or expressions.
7580 -- This replacement is achieved as follows: before inheriting R's
7581 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
7582 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
7583 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
7584 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
7585 -- by String (1 .. X).
7587 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
7589 -- We explain here the rules governing private type extensions relevant to
7590 -- type derivation. These rules are explained on the following example:
7592 -- type D [(...)] is new A [(...)] with private; <-- partial view
7593 -- type D [(...)] is new P [(...)] with null record; <-- full view
7595 -- Type A is called the ancestor subtype of the private extension.
7596 -- Type P is the parent type of the full view of the private extension. It
7597 -- must be A or a type derived from A.
7599 -- The rules concerning the discriminants of private type extensions are
7602 -- o If a private extension inherits known discriminants from the ancestor
7603 -- subtype, then the full view must also inherit its discriminants from
7604 -- the ancestor subtype and the parent subtype of the full view must be
7605 -- constrained if and only if the ancestor subtype is constrained.
7607 -- o If a partial view has unknown discriminants, then the full view may
7608 -- define a definite or an indefinite subtype, with or without
7611 -- o If a partial view has neither known nor unknown discriminants, then
7612 -- the full view must define a definite subtype.
7614 -- o If the ancestor subtype of a private extension has constrained
7615 -- discriminants, then the parent subtype of the full view must impose a
7616 -- statically matching constraint on those discriminants.
7618 -- This means that only the following forms of private extensions are
7621 -- type D is new A with private; <-- partial view
7622 -- type D is new P with null record; <-- full view
7624 -- If A has no discriminants than P has no discriminants, otherwise P must
7625 -- inherit A's discriminants.
7627 -- type D is new A (...) with private; <-- partial view
7628 -- type D is new P (:::) with null record; <-- full view
7630 -- P must inherit A's discriminants and (...) and (:::) must statically
7633 -- subtype A is R (...);
7634 -- type D is new A with private; <-- partial view
7635 -- type D is new P with null record; <-- full view
7637 -- P must have inherited R's discriminants and must be derived from A or
7638 -- any of its subtypes.
7640 -- type D (..) is new A with private; <-- partial view
7641 -- type D (..) is new P [(:::)] with null record; <-- full view
7643 -- No specific constraints on P's discriminants or constraint (:::).
7644 -- Note that A can be unconstrained, but the parent subtype P must either
7645 -- be constrained or (:::) must be present.
7647 -- type D (..) is new A [(...)] with private; <-- partial view
7648 -- type D (..) is new P [(:::)] with null record; <-- full view
7650 -- P's constraints on A's discriminants must statically match those
7651 -- imposed by (...).
7653 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
7655 -- The full view of a private extension is handled exactly as described
7656 -- above. The model chose for the private view of a private extension is
7657 -- the same for what concerns discriminants (i.e. they receive the same
7658 -- treatment as in the tagged case). However, the private view of the
7659 -- private extension always inherits the components of the parent base,
7660 -- without replacing any discriminant reference. Strictly speaking this is
7661 -- incorrect. However, Gigi never uses this view to generate code so this
7662 -- is a purely semantic issue. In theory, a set of transformations similar
7663 -- to those given in 5. and 6. above could be applied to private views of
7664 -- private extensions to have the same model of component inheritance as
7665 -- for non private extensions. However, this is not done because it would
7666 -- further complicate private type processing. Semantically speaking, this
7667 -- leaves us in an uncomfortable situation. As an example consider:
7670 -- type R (D : integer) is tagged record
7671 -- S : String (1 .. D);
7673 -- procedure P (X : R);
7674 -- type T is new R (1) with private;
7676 -- type T is new R (1) with null record;
7679 -- This is transformed into:
7682 -- type R (D : integer) is tagged record
7683 -- S : String (1 .. D);
7685 -- procedure P (X : R);
7686 -- type T is new R (1) with private;
7688 -- type BaseT is new R with null record;
7689 -- subtype T is BaseT (1);
7692 -- (strictly speaking the above is incorrect Ada)
7694 -- From the semantic standpoint the private view of private extension T
7695 -- should be flagged as constrained since one can clearly have
7699 -- in a unit withing Pack. However, when deriving subprograms for the
7700 -- private view of private extension T, T must be seen as unconstrained
7701 -- since T has discriminants (this is a constraint of the current
7702 -- subprogram derivation model). Thus, when processing the private view of
7703 -- a private extension such as T, we first mark T as unconstrained, we
7704 -- process it, we perform program derivation and just before returning from
7705 -- Build_Derived_Record_Type we mark T as constrained.
7707 -- ??? Are there are other uncomfortable cases that we will have to
7710 -- 10. RECORD_TYPE_WITH_PRIVATE complications
7712 -- Types that are derived from a visible record type and have a private
7713 -- extension present other peculiarities. They behave mostly like private
7714 -- types, but if they have primitive operations defined, these will not
7715 -- have the proper signatures for further inheritance, because other
7716 -- primitive operations will use the implicit base that we define for
7717 -- private derivations below. This affect subprogram inheritance (see
7718 -- Derive_Subprograms for details). We also derive the implicit base from
7719 -- the base type of the full view, so that the implicit base is a record
7720 -- type and not another private type, This avoids infinite loops.
7722 procedure Build_Derived_Record_Type
7724 Parent_Type : Entity_Id;
7725 Derived_Type : Entity_Id;
7726 Derive_Subps : Boolean := True)
7728 function Implements_Ghost_Interface (Typ : Entity_Id) return Boolean;
7729 -- Determine whether type Typ implements at least one Ghost interface
7731 --------------------------------
7732 -- Implements_Ghost_Interface --
7733 --------------------------------
7735 function Implements_Ghost_Interface (Typ : Entity_Id) return Boolean is
7736 Iface_Elmt : Elmt_Id;
7738 -- Traverse the list of interfaces looking for a Ghost interface
7740 if Is_Tagged_Type (Typ) and then Present (Interfaces (Typ)) then
7741 Iface_Elmt := First_Elmt (Interfaces (Typ));
7742 while Present (Iface_Elmt) loop
7743 if Is_Ghost_Entity (Node (Iface_Elmt)) then
7747 Next_Elmt (Iface_Elmt);
7752 end Implements_Ghost_Interface;
7756 Discriminant_Specs : constant Boolean :=
7757 Present (Discriminant_Specifications (N));
7758 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
7759 Loc : constant Source_Ptr := Sloc (N);
7760 Private_Extension : constant Boolean :=
7761 Nkind (N) = N_Private_Extension_Declaration;
7762 Assoc_List : Elist_Id;
7763 Constraint_Present : Boolean;
7765 Discrim : Entity_Id;
7767 Inherit_Discrims : Boolean := False;
7768 Last_Discrim : Entity_Id;
7769 New_Base : Entity_Id;
7771 New_Discrs : Elist_Id;
7772 New_Indic : Node_Id;
7773 Parent_Base : Entity_Id;
7774 Save_Etype : Entity_Id;
7775 Save_Discr_Constr : Elist_Id;
7776 Save_Next_Entity : Entity_Id;
7779 Discs : Elist_Id := New_Elmt_List;
7780 -- An empty Discs list means that there were no constraints in the
7781 -- subtype indication or that there was an error processing it.
7783 -- Start of processing for Build_Derived_Record_Type
7786 if Ekind (Parent_Type) = E_Record_Type_With_Private
7787 and then Present (Full_View (Parent_Type))
7788 and then Has_Discriminants (Parent_Type)
7790 Parent_Base := Base_Type (Full_View (Parent_Type));
7792 Parent_Base := Base_Type (Parent_Type);
7795 -- AI05-0115 : if this is a derivation from a private type in some
7796 -- other scope that may lead to invisible components for the derived
7797 -- type, mark it accordingly.
7799 if Is_Private_Type (Parent_Type) then
7800 if Scope (Parent_Type) = Scope (Derived_Type) then
7803 elsif In_Open_Scopes (Scope (Parent_Type))
7804 and then In_Private_Part (Scope (Parent_Type))
7809 Set_Has_Private_Ancestor (Derived_Type);
7813 Set_Has_Private_Ancestor
7814 (Derived_Type, Has_Private_Ancestor (Parent_Type));
7817 -- Before we start the previously documented transformations, here is
7818 -- little fix for size and alignment of tagged types. Normally when we
7819 -- derive type D from type P, we copy the size and alignment of P as the
7820 -- default for D, and in the absence of explicit representation clauses
7821 -- for D, the size and alignment are indeed the same as the parent.
7823 -- But this is wrong for tagged types, since fields may be added, and
7824 -- the default size may need to be larger, and the default alignment may
7825 -- need to be larger.
7827 -- We therefore reset the size and alignment fields in the tagged case.
7828 -- Note that the size and alignment will in any case be at least as
7829 -- large as the parent type (since the derived type has a copy of the
7830 -- parent type in the _parent field)
7832 -- The type is also marked as being tagged here, which is needed when
7833 -- processing components with a self-referential anonymous access type
7834 -- in the call to Check_Anonymous_Access_Components below. Note that
7835 -- this flag is also set later on for completeness.
7838 Set_Is_Tagged_Type (Derived_Type);
7839 Init_Size_Align (Derived_Type);
7842 -- STEP 0a: figure out what kind of derived type declaration we have
7844 if Private_Extension then
7846 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
7847 Set_Default_SSO (Derived_Type);
7850 Type_Def := Type_Definition (N);
7852 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7853 -- Parent_Base can be a private type or private extension. However,
7854 -- for tagged types with an extension the newly added fields are
7855 -- visible and hence the Derived_Type is always an E_Record_Type.
7856 -- (except that the parent may have its own private fields).
7857 -- For untagged types we preserve the Ekind of the Parent_Base.
7859 if Present (Record_Extension_Part (Type_Def)) then
7860 Set_Ekind (Derived_Type, E_Record_Type);
7861 Set_Default_SSO (Derived_Type);
7863 -- Create internal access types for components with anonymous
7866 if Ada_Version >= Ada_2005 then
7867 Check_Anonymous_Access_Components
7868 (N, Derived_Type, Derived_Type,
7869 Component_List (Record_Extension_Part (Type_Def)));
7873 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7877 -- Indic can either be an N_Identifier if the subtype indication
7878 -- contains no constraint or an N_Subtype_Indication if the subtype
7879 -- indication has a constraint.
7881 Indic := Subtype_Indication (Type_Def);
7882 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
7884 -- Check that the type has visible discriminants. The type may be
7885 -- a private type with unknown discriminants whose full view has
7886 -- discriminants which are invisible.
7888 if Constraint_Present then
7889 if not Has_Discriminants (Parent_Base)
7891 (Has_Unknown_Discriminants (Parent_Base)
7892 and then Is_Private_Type (Parent_Base))
7895 ("invalid constraint: type has no discriminant",
7896 Constraint (Indic));
7898 Constraint_Present := False;
7899 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7901 elsif Is_Constrained (Parent_Type) then
7903 ("invalid constraint: parent type is already constrained",
7904 Constraint (Indic));
7906 Constraint_Present := False;
7907 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
7911 -- STEP 0b: If needed, apply transformation given in point 5. above
7913 if not Private_Extension
7914 and then Has_Discriminants (Parent_Type)
7915 and then not Discriminant_Specs
7916 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
7918 -- First, we must analyze the constraint (see comment in point 5.)
7919 -- The constraint may come from the subtype indication of the full
7922 if Constraint_Present then
7923 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
7925 -- If there is no explicit constraint, there might be one that is
7926 -- inherited from a constrained parent type. In that case verify that
7927 -- it conforms to the constraint in the partial view. In perverse
7928 -- cases the parent subtypes of the partial and full view can have
7929 -- different constraints.
7931 elsif Present (Stored_Constraint (Parent_Type)) then
7932 New_Discrs := Stored_Constraint (Parent_Type);
7935 New_Discrs := No_Elist;
7938 if Has_Discriminants (Derived_Type)
7939 and then Has_Private_Declaration (Derived_Type)
7940 and then Present (Discriminant_Constraint (Derived_Type))
7941 and then Present (New_Discrs)
7943 -- Verify that constraints of the full view statically match
7944 -- those given in the partial view.
7950 C1 := First_Elmt (New_Discrs);
7951 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
7952 while Present (C1) and then Present (C2) loop
7953 if Fully_Conformant_Expressions (Node (C1), Node (C2))
7955 (Is_OK_Static_Expression (Node (C1))
7956 and then Is_OK_Static_Expression (Node (C2))
7958 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
7963 if Constraint_Present then
7965 ("constraint not conformant to previous declaration",
7969 ("constraint of full view is incompatible "
7970 & "with partial view", N);
7980 -- Insert and analyze the declaration for the unconstrained base type
7982 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
7985 Make_Full_Type_Declaration (Loc,
7986 Defining_Identifier => New_Base,
7988 Make_Derived_Type_Definition (Loc,
7989 Abstract_Present => Abstract_Present (Type_Def),
7990 Limited_Present => Limited_Present (Type_Def),
7991 Subtype_Indication =>
7992 New_Occurrence_Of (Parent_Base, Loc),
7993 Record_Extension_Part =>
7994 Relocate_Node (Record_Extension_Part (Type_Def)),
7995 Interface_List => Interface_List (Type_Def)));
7997 Set_Parent (New_Decl, Parent (N));
7998 Mark_Rewrite_Insertion (New_Decl);
7999 Insert_Before (N, New_Decl);
8001 -- In the extension case, make sure ancestor is frozen appropriately
8002 -- (see also non-discriminated case below).
8004 if Present (Record_Extension_Part (Type_Def))
8005 or else Is_Interface (Parent_Base)
8007 Freeze_Before (New_Decl, Parent_Type);
8010 -- Note that this call passes False for the Derive_Subps parameter
8011 -- because subprogram derivation is deferred until after creating
8012 -- the subtype (see below).
8015 (New_Decl, Parent_Base, New_Base,
8016 Is_Completion => False, Derive_Subps => False);
8018 -- ??? This needs re-examination to determine whether the
8019 -- above call can simply be replaced by a call to Analyze.
8021 Set_Analyzed (New_Decl);
8023 -- Insert and analyze the declaration for the constrained subtype
8025 if Constraint_Present then
8027 Make_Subtype_Indication (Loc,
8028 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8029 Constraint => Relocate_Node (Constraint (Indic)));
8033 Constr_List : constant List_Id := New_List;
8038 C := First_Elmt (Discriminant_Constraint (Parent_Type));
8039 while Present (C) loop
8042 -- It is safe here to call New_Copy_Tree since
8043 -- Force_Evaluation was called on each constraint in
8044 -- Build_Discriminant_Constraints.
8046 Append (New_Copy_Tree (Expr), To => Constr_List);
8052 Make_Subtype_Indication (Loc,
8053 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
8055 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
8060 Make_Subtype_Declaration (Loc,
8061 Defining_Identifier => Derived_Type,
8062 Subtype_Indication => New_Indic));
8066 -- Derivation of subprograms must be delayed until the full subtype
8067 -- has been established, to ensure proper overriding of subprograms
8068 -- inherited by full types. If the derivations occurred as part of
8069 -- the call to Build_Derived_Type above, then the check for type
8070 -- conformance would fail because earlier primitive subprograms
8071 -- could still refer to the full type prior the change to the new
8072 -- subtype and hence would not match the new base type created here.
8073 -- Subprograms are not derived, however, when Derive_Subps is False
8074 -- (since otherwise there could be redundant derivations).
8076 if Derive_Subps then
8077 Derive_Subprograms (Parent_Type, Derived_Type);
8080 -- For tagged types the Discriminant_Constraint of the new base itype
8081 -- is inherited from the first subtype so that no subtype conformance
8082 -- problem arise when the first subtype overrides primitive
8083 -- operations inherited by the implicit base type.
8086 Set_Discriminant_Constraint
8087 (New_Base, Discriminant_Constraint (Derived_Type));
8093 -- If we get here Derived_Type will have no discriminants or it will be
8094 -- a discriminated unconstrained base type.
8096 -- STEP 1a: perform preliminary actions/checks for derived tagged types
8100 -- The parent type is frozen for non-private extensions (RM 13.14(7))
8101 -- The declaration of a specific descendant of an interface type
8102 -- freezes the interface type (RM 13.14).
8104 if not Private_Extension or else Is_Interface (Parent_Base) then
8105 Freeze_Before (N, Parent_Type);
8108 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
8109 -- cannot be declared at a deeper level than its parent type is
8110 -- removed. The check on derivation within a generic body is also
8111 -- relaxed, but there's a restriction that a derived tagged type
8112 -- cannot be declared in a generic body if it's derived directly
8113 -- or indirectly from a formal type of that generic.
8115 if Ada_Version >= Ada_2005 then
8116 if Present (Enclosing_Generic_Body (Derived_Type)) then
8118 Ancestor_Type : Entity_Id;
8121 -- Check to see if any ancestor of the derived type is a
8124 Ancestor_Type := Parent_Type;
8125 while not Is_Generic_Type (Ancestor_Type)
8126 and then Etype (Ancestor_Type) /= Ancestor_Type
8128 Ancestor_Type := Etype (Ancestor_Type);
8131 -- If the derived type does have a formal type as an
8132 -- ancestor, then it's an error if the derived type is
8133 -- declared within the body of the generic unit that
8134 -- declares the formal type in its generic formal part. It's
8135 -- sufficient to check whether the ancestor type is declared
8136 -- inside the same generic body as the derived type (such as
8137 -- within a nested generic spec), in which case the
8138 -- derivation is legal. If the formal type is declared
8139 -- outside of that generic body, then it's guaranteed that
8140 -- the derived type is declared within the generic body of
8141 -- the generic unit declaring the formal type.
8143 if Is_Generic_Type (Ancestor_Type)
8144 and then Enclosing_Generic_Body (Ancestor_Type) /=
8145 Enclosing_Generic_Body (Derived_Type)
8148 ("parent type of& must not be descendant of formal type"
8149 & " of an enclosing generic body",
8150 Indic, Derived_Type);
8155 elsif Type_Access_Level (Derived_Type) /=
8156 Type_Access_Level (Parent_Type)
8157 and then not Is_Generic_Type (Derived_Type)
8159 if Is_Controlled (Parent_Type) then
8161 ("controlled type must be declared at the library level",
8165 ("type extension at deeper accessibility level than parent",
8171 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
8174 and then GB /= Enclosing_Generic_Body (Parent_Base)
8177 ("parent type of& must not be outside generic body"
8179 Indic, Derived_Type);
8185 -- Ada 2005 (AI-251)
8187 if Ada_Version >= Ada_2005 and then Is_Tagged then
8189 -- "The declaration of a specific descendant of an interface type
8190 -- freezes the interface type" (RM 13.14).
8195 if Is_Non_Empty_List (Interface_List (Type_Def)) then
8196 Iface := First (Interface_List (Type_Def));
8197 while Present (Iface) loop
8198 Freeze_Before (N, Etype (Iface));
8205 -- STEP 1b : preliminary cleanup of the full view of private types
8207 -- If the type is already marked as having discriminants, then it's the
8208 -- completion of a private type or private extension and we need to
8209 -- retain the discriminants from the partial view if the current
8210 -- declaration has Discriminant_Specifications so that we can verify
8211 -- conformance. However, we must remove any existing components that
8212 -- were inherited from the parent (and attached in Copy_And_Swap)
8213 -- because the full type inherits all appropriate components anyway, and
8214 -- we do not want the partial view's components interfering.
8216 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
8217 Discrim := First_Discriminant (Derived_Type);
8219 Last_Discrim := Discrim;
8220 Next_Discriminant (Discrim);
8221 exit when No (Discrim);
8224 Set_Last_Entity (Derived_Type, Last_Discrim);
8226 -- In all other cases wipe out the list of inherited components (even
8227 -- inherited discriminants), it will be properly rebuilt here.
8230 Set_First_Entity (Derived_Type, Empty);
8231 Set_Last_Entity (Derived_Type, Empty);
8234 -- STEP 1c: Initialize some flags for the Derived_Type
8236 -- The following flags must be initialized here so that
8237 -- Process_Discriminants can check that discriminants of tagged types do
8238 -- not have a default initial value and that access discriminants are
8239 -- only specified for limited records. For completeness, these flags are
8240 -- also initialized along with all the other flags below.
8242 -- AI-419: Limitedness is not inherited from an interface parent, so to
8243 -- be limited in that case the type must be explicitly declared as
8244 -- limited. However, task and protected interfaces are always limited.
8246 if Limited_Present (Type_Def) then
8247 Set_Is_Limited_Record (Derived_Type);
8249 elsif Is_Limited_Record (Parent_Type)
8250 or else (Present (Full_View (Parent_Type))
8251 and then Is_Limited_Record (Full_View (Parent_Type)))
8253 if not Is_Interface (Parent_Type)
8254 or else Is_Synchronized_Interface (Parent_Type)
8255 or else Is_Protected_Interface (Parent_Type)
8256 or else Is_Task_Interface (Parent_Type)
8258 Set_Is_Limited_Record (Derived_Type);
8262 -- STEP 2a: process discriminants of derived type if any
8264 Push_Scope (Derived_Type);
8266 if Discriminant_Specs then
8267 Set_Has_Unknown_Discriminants (Derived_Type, False);
8269 -- The following call initializes fields Has_Discriminants and
8270 -- Discriminant_Constraint, unless we are processing the completion
8271 -- of a private type declaration.
8273 Check_Or_Process_Discriminants (N, Derived_Type);
8275 -- For untagged types, the constraint on the Parent_Type must be
8276 -- present and is used to rename the discriminants.
8278 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
8279 Error_Msg_N ("untagged parent must have discriminants", Indic);
8281 elsif not Is_Tagged and then not Constraint_Present then
8283 ("discriminant constraint needed for derived untagged records",
8286 -- Otherwise the parent subtype must be constrained unless we have a
8287 -- private extension.
8289 elsif not Constraint_Present
8290 and then not Private_Extension
8291 and then not Is_Constrained (Parent_Type)
8294 ("unconstrained type not allowed in this context", Indic);
8296 elsif Constraint_Present then
8297 -- The following call sets the field Corresponding_Discriminant
8298 -- for the discriminants in the Derived_Type.
8300 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
8302 -- For untagged types all new discriminants must rename
8303 -- discriminants in the parent. For private extensions new
8304 -- discriminants cannot rename old ones (implied by [7.3(13)]).
8306 Discrim := First_Discriminant (Derived_Type);
8307 while Present (Discrim) loop
8309 and then No (Corresponding_Discriminant (Discrim))
8312 ("new discriminants must constrain old ones", Discrim);
8314 elsif Private_Extension
8315 and then Present (Corresponding_Discriminant (Discrim))
8318 ("only static constraints allowed for parent"
8319 & " discriminants in the partial view", Indic);
8323 -- If a new discriminant is used in the constraint, then its
8324 -- subtype must be statically compatible with the parent
8325 -- discriminant's subtype (3.7(15)).
8327 -- However, if the record contains an array constrained by
8328 -- the discriminant but with some different bound, the compiler
8329 -- attemps to create a smaller range for the discriminant type.
8330 -- (See exp_ch3.Adjust_Discriminants). In this case, where
8331 -- the discriminant type is a scalar type, the check must use
8332 -- the original discriminant type in the parent declaration.
8335 Corr_Disc : constant Entity_Id :=
8336 Corresponding_Discriminant (Discrim);
8337 Disc_Type : constant Entity_Id := Etype (Discrim);
8338 Corr_Type : Entity_Id;
8341 if Present (Corr_Disc) then
8342 if Is_Scalar_Type (Disc_Type) then
8344 Entity (Discriminant_Type (Parent (Corr_Disc)));
8346 Corr_Type := Etype (Corr_Disc);
8350 Subtypes_Statically_Compatible (Disc_Type, Corr_Type)
8353 ("subtype must be compatible "
8354 & "with parent discriminant",
8360 Next_Discriminant (Discrim);
8363 -- Check whether the constraints of the full view statically
8364 -- match those imposed by the parent subtype [7.3(13)].
8366 if Present (Stored_Constraint (Derived_Type)) then
8371 C1 := First_Elmt (Discs);
8372 C2 := First_Elmt (Stored_Constraint (Derived_Type));
8373 while Present (C1) and then Present (C2) loop
8375 Fully_Conformant_Expressions (Node (C1), Node (C2))
8378 ("not conformant with previous declaration",
8389 -- STEP 2b: No new discriminants, inherit discriminants if any
8392 if Private_Extension then
8393 Set_Has_Unknown_Discriminants
8395 Has_Unknown_Discriminants (Parent_Type)
8396 or else Unknown_Discriminants_Present (N));
8398 -- The partial view of the parent may have unknown discriminants,
8399 -- but if the full view has discriminants and the parent type is
8400 -- in scope they must be inherited.
8402 elsif Has_Unknown_Discriminants (Parent_Type)
8404 (not Has_Discriminants (Parent_Type)
8405 or else not In_Open_Scopes (Scope (Parent_Type)))
8407 Set_Has_Unknown_Discriminants (Derived_Type);
8410 if not Has_Unknown_Discriminants (Derived_Type)
8411 and then not Has_Unknown_Discriminants (Parent_Base)
8412 and then Has_Discriminants (Parent_Type)
8414 Inherit_Discrims := True;
8415 Set_Has_Discriminants
8416 (Derived_Type, True);
8417 Set_Discriminant_Constraint
8418 (Derived_Type, Discriminant_Constraint (Parent_Base));
8421 -- The following test is true for private types (remember
8422 -- transformation 5. is not applied to those) and in an error
8425 if Constraint_Present then
8426 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
8429 -- For now mark a new derived type as constrained only if it has no
8430 -- discriminants. At the end of Build_Derived_Record_Type we properly
8431 -- set this flag in the case of private extensions. See comments in
8432 -- point 9. just before body of Build_Derived_Record_Type.
8436 not (Inherit_Discrims
8437 or else Has_Unknown_Discriminants (Derived_Type)));
8440 -- STEP 3: initialize fields of derived type
8442 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
8443 Set_Stored_Constraint (Derived_Type, No_Elist);
8445 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
8446 -- but cannot be interfaces
8448 if not Private_Extension
8449 and then Ekind (Derived_Type) /= E_Private_Type
8450 and then Ekind (Derived_Type) /= E_Limited_Private_Type
8452 if Interface_Present (Type_Def) then
8453 Analyze_Interface_Declaration (Derived_Type, Type_Def);
8456 Set_Interfaces (Derived_Type, No_Elist);
8459 -- Fields inherited from the Parent_Type
8461 Set_Has_Specified_Layout
8462 (Derived_Type, Has_Specified_Layout (Parent_Type));
8463 Set_Is_Limited_Composite
8464 (Derived_Type, Is_Limited_Composite (Parent_Type));
8465 Set_Is_Private_Composite
8466 (Derived_Type, Is_Private_Composite (Parent_Type));
8468 if Is_Tagged_Type (Parent_Type) then
8469 Set_No_Tagged_Streams_Pragma
8470 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8473 -- Fields inherited from the Parent_Base
8475 Set_Has_Controlled_Component
8476 (Derived_Type, Has_Controlled_Component (Parent_Base));
8477 Set_Has_Non_Standard_Rep
8478 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8479 Set_Has_Primitive_Operations
8480 (Derived_Type, Has_Primitive_Operations (Parent_Base));
8482 -- Fields inherited from the Parent_Base in the non-private case
8484 if Ekind (Derived_Type) = E_Record_Type then
8485 Set_Has_Complex_Representation
8486 (Derived_Type, Has_Complex_Representation (Parent_Base));
8489 -- Fields inherited from the Parent_Base for record types
8491 if Is_Record_Type (Derived_Type) then
8493 Parent_Full : Entity_Id;
8496 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
8497 -- Parent_Base can be a private type or private extension. Go
8498 -- to the full view here to get the E_Record_Type specific flags.
8500 if Present (Full_View (Parent_Base)) then
8501 Parent_Full := Full_View (Parent_Base);
8503 Parent_Full := Parent_Base;
8506 Set_OK_To_Reorder_Components
8507 (Derived_Type, OK_To_Reorder_Components (Parent_Full));
8511 -- Set fields for private derived types
8513 if Is_Private_Type (Derived_Type) then
8514 Set_Depends_On_Private (Derived_Type, True);
8515 Set_Private_Dependents (Derived_Type, New_Elmt_List);
8517 -- Inherit fields from non private record types. If this is the
8518 -- completion of a derivation from a private type, the parent itself
8519 -- is private, and the attributes come from its full view, which must
8523 if Is_Private_Type (Parent_Base)
8524 and then not Is_Record_Type (Parent_Base)
8526 Set_Component_Alignment
8527 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
8529 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
8531 Set_Component_Alignment
8532 (Derived_Type, Component_Alignment (Parent_Base));
8534 (Derived_Type, C_Pass_By_Copy (Parent_Base));
8538 -- Set fields for tagged types
8541 Set_Direct_Primitive_Operations (Derived_Type, New_Elmt_List);
8543 -- All tagged types defined in Ada.Finalization are controlled
8545 if Chars (Scope (Derived_Type)) = Name_Finalization
8546 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
8547 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
8549 Set_Is_Controlled (Derived_Type);
8551 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
8554 -- Minor optimization: there is no need to generate the class-wide
8555 -- entity associated with an underlying record view.
8557 if not Is_Underlying_Record_View (Derived_Type) then
8558 Make_Class_Wide_Type (Derived_Type);
8561 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
8563 if Has_Discriminants (Derived_Type)
8564 and then Constraint_Present
8566 Set_Stored_Constraint
8567 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
8570 if Ada_Version >= Ada_2005 then
8572 Ifaces_List : Elist_Id;
8575 -- Checks rules 3.9.4 (13/2 and 14/2)
8577 if Comes_From_Source (Derived_Type)
8578 and then not Is_Private_Type (Derived_Type)
8579 and then Is_Interface (Parent_Type)
8580 and then not Is_Interface (Derived_Type)
8582 if Is_Task_Interface (Parent_Type) then
8584 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
8587 elsif Is_Protected_Interface (Parent_Type) then
8589 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
8594 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
8596 Check_Interfaces (N, Type_Def);
8598 -- Ada 2005 (AI-251): Collect the list of progenitors that are
8599 -- not already in the parents.
8603 Ifaces_List => Ifaces_List,
8604 Exclude_Parents => True);
8606 Set_Interfaces (Derived_Type, Ifaces_List);
8608 -- If the derived type is the anonymous type created for
8609 -- a declaration whose parent has a constraint, propagate
8610 -- the interface list to the source type. This must be done
8611 -- prior to the completion of the analysis of the source type
8612 -- because the components in the extension may contain current
8613 -- instances whose legality depends on some ancestor.
8615 if Is_Itype (Derived_Type) then
8617 Def : constant Node_Id :=
8618 Associated_Node_For_Itype (Derived_Type);
8621 and then Nkind (Def) = N_Full_Type_Declaration
8624 (Defining_Identifier (Def), Ifaces_List);
8629 -- A type extension is automatically Ghost when one of its
8630 -- progenitors is Ghost (SPARK RM 6.9(9)). This property is
8631 -- also inherited when the parent type is Ghost, but this is
8632 -- done in Build_Derived_Type as the mechanism also handles
8633 -- untagged derivations.
8635 if Implements_Ghost_Interface (Derived_Type) then
8636 Set_Is_Ghost_Entity (Derived_Type);
8642 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
8643 Set_Has_Non_Standard_Rep
8644 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
8647 -- STEP 4: Inherit components from the parent base and constrain them.
8648 -- Apply the second transformation described in point 6. above.
8650 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
8651 or else not Has_Discriminants (Parent_Type)
8652 or else not Is_Constrained (Parent_Type)
8656 Constrs := Discriminant_Constraint (Parent_Type);
8661 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
8663 -- STEP 5a: Copy the parent record declaration for untagged types
8665 if not Is_Tagged then
8667 -- Discriminant_Constraint (Derived_Type) has been properly
8668 -- constructed. Save it and temporarily set it to Empty because we
8669 -- do not want the call to New_Copy_Tree below to mess this list.
8671 if Has_Discriminants (Derived_Type) then
8672 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
8673 Set_Discriminant_Constraint (Derived_Type, No_Elist);
8675 Save_Discr_Constr := No_Elist;
8678 -- Save the Etype field of Derived_Type. It is correctly set now,
8679 -- but the call to New_Copy tree may remap it to point to itself,
8680 -- which is not what we want. Ditto for the Next_Entity field.
8682 Save_Etype := Etype (Derived_Type);
8683 Save_Next_Entity := Next_Entity (Derived_Type);
8685 -- Assoc_List maps all stored discriminants in the Parent_Base to
8686 -- stored discriminants in the Derived_Type. It is fundamental that
8687 -- no types or itypes with discriminants other than the stored
8688 -- discriminants appear in the entities declared inside
8689 -- Derived_Type, since the back end cannot deal with it.
8693 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
8695 -- Restore the fields saved prior to the New_Copy_Tree call
8696 -- and compute the stored constraint.
8698 Set_Etype (Derived_Type, Save_Etype);
8699 Set_Next_Entity (Derived_Type, Save_Next_Entity);
8701 if Has_Discriminants (Derived_Type) then
8702 Set_Discriminant_Constraint
8703 (Derived_Type, Save_Discr_Constr);
8704 Set_Stored_Constraint
8705 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
8706 Replace_Components (Derived_Type, New_Decl);
8707 Set_Has_Implicit_Dereference
8708 (Derived_Type, Has_Implicit_Dereference (Parent_Type));
8711 -- Insert the new derived type declaration
8713 Rewrite (N, New_Decl);
8715 -- STEP 5b: Complete the processing for record extensions in generics
8717 -- There is no completion for record extensions declared in the
8718 -- parameter part of a generic, so we need to complete processing for
8719 -- these generic record extensions here. The Record_Type_Definition call
8720 -- will change the Ekind of the components from E_Void to E_Component.
8722 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
8723 Record_Type_Definition (Empty, Derived_Type);
8725 -- STEP 5c: Process the record extension for non private tagged types
8727 elsif not Private_Extension then
8728 Expand_Record_Extension (Derived_Type, Type_Def);
8730 -- Note : previously in ASIS mode we set the Parent_Subtype of the
8731 -- derived type to propagate some semantic information. This led
8732 -- to other ASIS failures and has been removed.
8734 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
8735 -- implemented interfaces if we are in expansion mode
8738 and then Has_Interfaces (Derived_Type)
8740 Add_Interface_Tag_Components (N, Derived_Type);
8743 -- Analyze the record extension
8745 Record_Type_Definition
8746 (Record_Extension_Part (Type_Def), Derived_Type);
8751 -- Nothing else to do if there is an error in the derivation.
8752 -- An unusual case: the full view may be derived from a type in an
8753 -- instance, when the partial view was used illegally as an actual
8754 -- in that instance, leading to a circular definition.
8756 if Etype (Derived_Type) = Any_Type
8757 or else Etype (Parent_Type) = Derived_Type
8762 -- Set delayed freeze and then derive subprograms, we need to do
8763 -- this in this order so that derived subprograms inherit the
8764 -- derived freeze if necessary.
8766 Set_Has_Delayed_Freeze (Derived_Type);
8768 if Derive_Subps then
8769 Derive_Subprograms (Parent_Type, Derived_Type);
8772 -- If we have a private extension which defines a constrained derived
8773 -- type mark as constrained here after we have derived subprograms. See
8774 -- comment on point 9. just above the body of Build_Derived_Record_Type.
8776 if Private_Extension and then Inherit_Discrims then
8777 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
8778 Set_Is_Constrained (Derived_Type, True);
8779 Set_Discriminant_Constraint (Derived_Type, Discs);
8781 elsif Is_Constrained (Parent_Type) then
8783 (Derived_Type, True);
8784 Set_Discriminant_Constraint
8785 (Derived_Type, Discriminant_Constraint (Parent_Type));
8789 -- Update the class-wide type, which shares the now-completed entity
8790 -- list with its specific type. In case of underlying record views,
8791 -- we do not generate the corresponding class wide entity.
8794 and then not Is_Underlying_Record_View (Derived_Type)
8797 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
8799 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
8802 Check_Function_Writable_Actuals (N);
8803 end Build_Derived_Record_Type;
8805 ------------------------
8806 -- Build_Derived_Type --
8807 ------------------------
8809 procedure Build_Derived_Type
8811 Parent_Type : Entity_Id;
8812 Derived_Type : Entity_Id;
8813 Is_Completion : Boolean;
8814 Derive_Subps : Boolean := True)
8816 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
8819 -- Set common attributes
8821 Set_Scope (Derived_Type, Current_Scope);
8823 Set_Etype (Derived_Type, Parent_Base);
8824 Set_Ekind (Derived_Type, Ekind (Parent_Base));
8825 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
8826 Set_Has_Protected (Derived_Type, Has_Protected (Parent_Base));
8828 Set_Size_Info (Derived_Type, Parent_Type);
8829 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
8830 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
8831 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
8832 Set_Is_Volatile (Derived_Type, Is_Volatile (Parent_Type));
8834 if Is_Tagged_Type (Derived_Type) then
8835 Set_No_Tagged_Streams_Pragma
8836 (Derived_Type, No_Tagged_Streams_Pragma (Parent_Type));
8839 -- If the parent has primitive routines, set the derived type link
8841 if Has_Primitive_Operations (Parent_Type) then
8842 Set_Derived_Type_Link (Parent_Base, Derived_Type);
8845 -- If the parent type is a private subtype, the convention on the base
8846 -- type may be set in the private part, and not propagated to the
8847 -- subtype until later, so we obtain the convention from the base type.
8849 Set_Convention (Derived_Type, Convention (Parent_Base));
8851 -- Set SSO default for record or array type
8853 if (Is_Array_Type (Derived_Type) or else Is_Record_Type (Derived_Type))
8854 and then Is_Base_Type (Derived_Type)
8856 Set_Default_SSO (Derived_Type);
8859 -- Propagate invariant information. The new type has invariants if
8860 -- they are inherited from the parent type, and these invariants can
8861 -- be further inherited, so both flags are set.
8863 -- We similarly inherit predicates
8865 if Has_Predicates (Parent_Type) then
8866 Set_Has_Predicates (Derived_Type);
8869 -- The derived type inherits the representation clauses of the parent
8871 Inherit_Rep_Item_Chain (Derived_Type, Parent_Type);
8873 -- Propagate the attributes related to pragma Default_Initial_Condition
8874 -- from the parent type to the private extension. A derived type always
8875 -- inherits the default initial condition flag from the parent type. If
8876 -- the derived type carries its own Default_Initial_Condition pragma,
8877 -- the flag is later reset in Analyze_Pragma. Note that both flags are
8878 -- mutually exclusive.
8880 Propagate_Default_Init_Cond_Attributes
8881 (From_Typ => Parent_Type,
8882 To_Typ => Derived_Type,
8883 Parent_To_Derivation => True);
8885 -- If the parent type has delayed rep aspects, then mark the derived
8886 -- type as possibly inheriting a delayed rep aspect.
8888 if Has_Delayed_Rep_Aspects (Parent_Type) then
8889 Set_May_Inherit_Delayed_Rep_Aspects (Derived_Type);
8892 -- Propagate the attributes related to pragma Ghost from the parent type
8893 -- to the derived type or type extension (SPARK RM 6.9(9)).
8895 if Is_Ghost_Entity (Parent_Type) then
8896 Set_Is_Ghost_Entity (Derived_Type);
8899 -- Type dependent processing
8901 case Ekind (Parent_Type) is
8902 when Numeric_Kind =>
8903 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
8906 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
8910 | Class_Wide_Kind =>
8911 Build_Derived_Record_Type
8912 (N, Parent_Type, Derived_Type, Derive_Subps);
8915 when Enumeration_Kind =>
8916 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
8919 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
8921 when Incomplete_Or_Private_Kind =>
8922 Build_Derived_Private_Type
8923 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
8925 -- For discriminated types, the derivation includes deriving
8926 -- primitive operations. For others it is done below.
8928 if Is_Tagged_Type (Parent_Type)
8929 or else Has_Discriminants (Parent_Type)
8930 or else (Present (Full_View (Parent_Type))
8931 and then Has_Discriminants (Full_View (Parent_Type)))
8936 when Concurrent_Kind =>
8937 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
8940 raise Program_Error;
8943 -- Nothing more to do if some error occurred
8945 if Etype (Derived_Type) = Any_Type then
8949 -- Set delayed freeze and then derive subprograms, we need to do this
8950 -- in this order so that derived subprograms inherit the derived freeze
8953 Set_Has_Delayed_Freeze (Derived_Type);
8955 if Derive_Subps then
8956 Derive_Subprograms (Parent_Type, Derived_Type);
8959 Set_Has_Primitive_Operations
8960 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
8961 end Build_Derived_Type;
8963 -----------------------
8964 -- Build_Discriminal --
8965 -----------------------
8967 procedure Build_Discriminal (Discrim : Entity_Id) is
8968 D_Minal : Entity_Id;
8969 CR_Disc : Entity_Id;
8972 -- A discriminal has the same name as the discriminant
8974 D_Minal := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8976 Set_Ekind (D_Minal, E_In_Parameter);
8977 Set_Mechanism (D_Minal, Default_Mechanism);
8978 Set_Etype (D_Minal, Etype (Discrim));
8979 Set_Scope (D_Minal, Current_Scope);
8981 Set_Discriminal (Discrim, D_Minal);
8982 Set_Discriminal_Link (D_Minal, Discrim);
8984 -- For task types, build at once the discriminants of the corresponding
8985 -- record, which are needed if discriminants are used in entry defaults
8986 -- and in family bounds.
8988 if Is_Concurrent_Type (Current_Scope)
8990 Is_Limited_Type (Current_Scope)
8992 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
8994 Set_Ekind (CR_Disc, E_In_Parameter);
8995 Set_Mechanism (CR_Disc, Default_Mechanism);
8996 Set_Etype (CR_Disc, Etype (Discrim));
8997 Set_Scope (CR_Disc, Current_Scope);
8998 Set_Discriminal_Link (CR_Disc, Discrim);
8999 Set_CR_Discriminant (Discrim, CR_Disc);
9001 end Build_Discriminal;
9003 ------------------------------------
9004 -- Build_Discriminant_Constraints --
9005 ------------------------------------
9007 function Build_Discriminant_Constraints
9010 Derived_Def : Boolean := False) return Elist_Id
9012 C : constant Node_Id := Constraint (Def);
9013 Nb_Discr : constant Nat := Number_Discriminants (T);
9015 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
9016 -- Saves the expression corresponding to a given discriminant in T
9018 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
9019 -- Return the Position number within array Discr_Expr of a discriminant
9020 -- D within the discriminant list of the discriminated type T.
9022 procedure Process_Discriminant_Expression
9025 -- If this is a discriminant constraint on a partial view, do not
9026 -- generate an overflow check on the discriminant expression. The check
9027 -- will be generated when constraining the full view. Otherwise the
9028 -- backend creates duplicate symbols for the temporaries corresponding
9029 -- to the expressions to be checked, causing spurious assembler errors.
9035 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
9039 Disc := First_Discriminant (T);
9040 for J in Discr_Expr'Range loop
9045 Next_Discriminant (Disc);
9048 -- Note: Since this function is called on discriminants that are
9049 -- known to belong to the discriminated type, falling through the
9050 -- loop with no match signals an internal compiler error.
9052 raise Program_Error;
9055 -------------------------------------
9056 -- Process_Discriminant_Expression --
9057 -------------------------------------
9059 procedure Process_Discriminant_Expression
9063 BDT : constant Entity_Id := Base_Type (Etype (D));
9066 -- If this is a discriminant constraint on a partial view, do
9067 -- not generate an overflow on the discriminant expression. The
9068 -- check will be generated when constraining the full view.
9070 if Is_Private_Type (T)
9071 and then Present (Full_View (T))
9073 Analyze_And_Resolve (Expr, BDT, Suppress => Overflow_Check);
9075 Analyze_And_Resolve (Expr, BDT);
9077 end Process_Discriminant_Expression;
9079 -- Declarations local to Build_Discriminant_Constraints
9083 Elist : constant Elist_Id := New_Elmt_List;
9091 Discrim_Present : Boolean := False;
9093 -- Start of processing for Build_Discriminant_Constraints
9096 -- The following loop will process positional associations only.
9097 -- For a positional association, the (single) discriminant is
9098 -- implicitly specified by position, in textual order (RM 3.7.2).
9100 Discr := First_Discriminant (T);
9101 Constr := First (Constraints (C));
9102 for D in Discr_Expr'Range loop
9103 exit when Nkind (Constr) = N_Discriminant_Association;
9106 Error_Msg_N ("too few discriminants given in constraint", C);
9107 return New_Elmt_List;
9109 elsif Nkind (Constr) = N_Range
9110 or else (Nkind (Constr) = N_Attribute_Reference
9111 and then Attribute_Name (Constr) = Name_Range)
9114 ("a range is not a valid discriminant constraint", Constr);
9115 Discr_Expr (D) := Error;
9118 Process_Discriminant_Expression (Constr, Discr);
9119 Discr_Expr (D) := Constr;
9122 Next_Discriminant (Discr);
9126 if No (Discr) and then Present (Constr) then
9127 Error_Msg_N ("too many discriminants given in constraint", Constr);
9128 return New_Elmt_List;
9131 -- Named associations can be given in any order, but if both positional
9132 -- and named associations are used in the same discriminant constraint,
9133 -- then positional associations must occur first, at their normal
9134 -- position. Hence once a named association is used, the rest of the
9135 -- discriminant constraint must use only named associations.
9137 while Present (Constr) loop
9139 -- Positional association forbidden after a named association
9141 if Nkind (Constr) /= N_Discriminant_Association then
9142 Error_Msg_N ("positional association follows named one", Constr);
9143 return New_Elmt_List;
9145 -- Otherwise it is a named association
9148 -- E records the type of the discriminants in the named
9149 -- association. All the discriminants specified in the same name
9150 -- association must have the same type.
9154 -- Search the list of discriminants in T to see if the simple name
9155 -- given in the constraint matches any of them.
9157 Id := First (Selector_Names (Constr));
9158 while Present (Id) loop
9161 -- If Original_Discriminant is present, we are processing a
9162 -- generic instantiation and this is an instance node. We need
9163 -- to find the name of the corresponding discriminant in the
9164 -- actual record type T and not the name of the discriminant in
9165 -- the generic formal. Example:
9168 -- type G (D : int) is private;
9170 -- subtype W is G (D => 1);
9172 -- type Rec (X : int) is record ... end record;
9173 -- package Q is new P (G => Rec);
9175 -- At the point of the instantiation, formal type G is Rec
9176 -- and therefore when reanalyzing "subtype W is G (D => 1);"
9177 -- which really looks like "subtype W is Rec (D => 1);" at
9178 -- the point of instantiation, we want to find the discriminant
9179 -- that corresponds to D in Rec, i.e. X.
9181 if Present (Original_Discriminant (Id))
9182 and then In_Instance
9184 Discr := Find_Corresponding_Discriminant (Id, T);
9188 Discr := First_Discriminant (T);
9189 while Present (Discr) loop
9190 if Chars (Discr) = Chars (Id) then
9195 Next_Discriminant (Discr);
9199 Error_Msg_N ("& does not match any discriminant", Id);
9200 return New_Elmt_List;
9202 -- If the parent type is a generic formal, preserve the
9203 -- name of the discriminant for subsequent instances.
9204 -- see comment at the beginning of this if statement.
9206 elsif Is_Generic_Type (Root_Type (T)) then
9207 Set_Original_Discriminant (Id, Discr);
9211 Position := Pos_Of_Discr (T, Discr);
9213 if Present (Discr_Expr (Position)) then
9214 Error_Msg_N ("duplicate constraint for discriminant&", Id);
9217 -- Each discriminant specified in the same named association
9218 -- must be associated with a separate copy of the
9219 -- corresponding expression.
9221 if Present (Next (Id)) then
9222 Expr := New_Copy_Tree (Expression (Constr));
9223 Set_Parent (Expr, Parent (Expression (Constr)));
9225 Expr := Expression (Constr);
9228 Discr_Expr (Position) := Expr;
9229 Process_Discriminant_Expression (Expr, Discr);
9232 -- A discriminant association with more than one discriminant
9233 -- name is only allowed if the named discriminants are all of
9234 -- the same type (RM 3.7.1(8)).
9237 E := Base_Type (Etype (Discr));
9239 elsif Base_Type (Etype (Discr)) /= E then
9241 ("all discriminants in an association " &
9242 "must have the same type", Id);
9252 -- A discriminant constraint must provide exactly one value for each
9253 -- discriminant of the type (RM 3.7.1(8)).
9255 for J in Discr_Expr'Range loop
9256 if No (Discr_Expr (J)) then
9257 Error_Msg_N ("too few discriminants given in constraint", C);
9258 return New_Elmt_List;
9262 -- Determine if there are discriminant expressions in the constraint
9264 for J in Discr_Expr'Range loop
9265 if Denotes_Discriminant
9266 (Discr_Expr (J), Check_Concurrent => True)
9268 Discrim_Present := True;
9272 -- Build an element list consisting of the expressions given in the
9273 -- discriminant constraint and apply the appropriate checks. The list
9274 -- is constructed after resolving any named discriminant associations
9275 -- and therefore the expressions appear in the textual order of the
9278 Discr := First_Discriminant (T);
9279 for J in Discr_Expr'Range loop
9280 if Discr_Expr (J) /= Error then
9281 Append_Elmt (Discr_Expr (J), Elist);
9283 -- If any of the discriminant constraints is given by a
9284 -- discriminant and we are in a derived type declaration we
9285 -- have a discriminant renaming. Establish link between new
9286 -- and old discriminant.
9288 if Denotes_Discriminant (Discr_Expr (J)) then
9290 Set_Corresponding_Discriminant
9291 (Entity (Discr_Expr (J)), Discr);
9294 -- Force the evaluation of non-discriminant expressions.
9295 -- If we have found a discriminant in the constraint 3.4(26)
9296 -- and 3.8(18) demand that no range checks are performed are
9297 -- after evaluation. If the constraint is for a component
9298 -- definition that has a per-object constraint, expressions are
9299 -- evaluated but not checked either. In all other cases perform
9303 if Discrim_Present then
9306 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
9308 Has_Per_Object_Constraint
9309 (Defining_Identifier (Parent (Parent (Def))))
9313 elsif Is_Access_Type (Etype (Discr)) then
9314 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
9317 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
9320 Force_Evaluation (Discr_Expr (J));
9323 -- Check that the designated type of an access discriminant's
9324 -- expression is not a class-wide type unless the discriminant's
9325 -- designated type is also class-wide.
9327 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
9328 and then not Is_Class_Wide_Type
9329 (Designated_Type (Etype (Discr)))
9330 and then Etype (Discr_Expr (J)) /= Any_Type
9331 and then Is_Class_Wide_Type
9332 (Designated_Type (Etype (Discr_Expr (J))))
9334 Wrong_Type (Discr_Expr (J), Etype (Discr));
9336 elsif Is_Access_Type (Etype (Discr))
9337 and then not Is_Access_Constant (Etype (Discr))
9338 and then Is_Access_Type (Etype (Discr_Expr (J)))
9339 and then Is_Access_Constant (Etype (Discr_Expr (J)))
9342 ("constraint for discriminant& must be access to variable",
9347 Next_Discriminant (Discr);
9351 end Build_Discriminant_Constraints;
9353 ---------------------------------
9354 -- Build_Discriminated_Subtype --
9355 ---------------------------------
9357 procedure Build_Discriminated_Subtype
9361 Related_Nod : Node_Id;
9362 For_Access : Boolean := False)
9364 Has_Discrs : constant Boolean := Has_Discriminants (T);
9365 Constrained : constant Boolean :=
9367 and then not Is_Empty_Elmt_List (Elist)
9368 and then not Is_Class_Wide_Type (T))
9369 or else Is_Constrained (T);
9372 if Ekind (T) = E_Record_Type then
9374 Set_Ekind (Def_Id, E_Private_Subtype);
9375 Set_Is_For_Access_Subtype (Def_Id, True);
9377 Set_Ekind (Def_Id, E_Record_Subtype);
9380 -- Inherit preelaboration flag from base, for types for which it
9381 -- may have been set: records, private types, protected types.
9383 Set_Known_To_Have_Preelab_Init
9384 (Def_Id, Known_To_Have_Preelab_Init (T));
9386 elsif Ekind (T) = E_Task_Type then
9387 Set_Ekind (Def_Id, E_Task_Subtype);
9389 elsif Ekind (T) = E_Protected_Type then
9390 Set_Ekind (Def_Id, E_Protected_Subtype);
9391 Set_Known_To_Have_Preelab_Init
9392 (Def_Id, Known_To_Have_Preelab_Init (T));
9394 elsif Is_Private_Type (T) then
9395 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
9396 Set_Known_To_Have_Preelab_Init
9397 (Def_Id, Known_To_Have_Preelab_Init (T));
9399 -- Private subtypes may have private dependents
9401 Set_Private_Dependents (Def_Id, New_Elmt_List);
9403 elsif Is_Class_Wide_Type (T) then
9404 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
9407 -- Incomplete type. Attach subtype to list of dependents, to be
9408 -- completed with full view of parent type, unless is it the
9409 -- designated subtype of a record component within an init_proc.
9410 -- This last case arises for a component of an access type whose
9411 -- designated type is incomplete (e.g. a Taft Amendment type).
9412 -- The designated subtype is within an inner scope, and needs no
9413 -- elaboration, because only the access type is needed in the
9414 -- initialization procedure.
9416 Set_Ekind (Def_Id, Ekind (T));
9418 if For_Access and then Within_Init_Proc then
9421 Append_Elmt (Def_Id, Private_Dependents (T));
9425 Set_Etype (Def_Id, T);
9426 Init_Size_Align (Def_Id);
9427 Set_Has_Discriminants (Def_Id, Has_Discrs);
9428 Set_Is_Constrained (Def_Id, Constrained);
9430 Set_First_Entity (Def_Id, First_Entity (T));
9431 Set_Last_Entity (Def_Id, Last_Entity (T));
9432 Set_Has_Implicit_Dereference
9433 (Def_Id, Has_Implicit_Dereference (T));
9435 -- If the subtype is the completion of a private declaration, there may
9436 -- have been representation clauses for the partial view, and they must
9437 -- be preserved. Build_Derived_Type chains the inherited clauses with
9438 -- the ones appearing on the extension. If this comes from a subtype
9439 -- declaration, all clauses are inherited.
9441 if No (First_Rep_Item (Def_Id)) then
9442 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
9445 if Is_Tagged_Type (T) then
9446 Set_Is_Tagged_Type (Def_Id);
9447 Set_No_Tagged_Streams_Pragma (Def_Id, No_Tagged_Streams_Pragma (T));
9448 Make_Class_Wide_Type (Def_Id);
9451 Set_Stored_Constraint (Def_Id, No_Elist);
9454 Set_Discriminant_Constraint (Def_Id, Elist);
9455 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
9458 if Is_Tagged_Type (T) then
9460 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
9461 -- concurrent record type (which has the list of primitive
9464 if Ada_Version >= Ada_2005
9465 and then Is_Concurrent_Type (T)
9467 Set_Corresponding_Record_Type (Def_Id,
9468 Corresponding_Record_Type (T));
9470 Set_Direct_Primitive_Operations (Def_Id,
9471 Direct_Primitive_Operations (T));
9474 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
9477 -- Subtypes introduced by component declarations do not need to be
9478 -- marked as delayed, and do not get freeze nodes, because the semantics
9479 -- verifies that the parents of the subtypes are frozen before the
9480 -- enclosing record is frozen.
9482 if not Is_Type (Scope (Def_Id)) then
9483 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
9485 if Is_Private_Type (T)
9486 and then Present (Full_View (T))
9488 Conditional_Delay (Def_Id, Full_View (T));
9490 Conditional_Delay (Def_Id, T);
9494 if Is_Record_Type (T) then
9495 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
9498 and then not Is_Empty_Elmt_List (Elist)
9499 and then not For_Access
9501 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
9502 elsif not For_Access then
9503 Set_Cloned_Subtype (Def_Id, T);
9506 end Build_Discriminated_Subtype;
9508 ---------------------------
9509 -- Build_Itype_Reference --
9510 ---------------------------
9512 procedure Build_Itype_Reference
9516 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
9519 -- Itype references are only created for use by the back-end
9521 if Inside_A_Generic then
9524 Set_Itype (IR, Ityp);
9525 Insert_After (Nod, IR);
9527 end Build_Itype_Reference;
9529 ------------------------
9530 -- Build_Scalar_Bound --
9531 ------------------------
9533 function Build_Scalar_Bound
9536 Der_T : Entity_Id) return Node_Id
9538 New_Bound : Entity_Id;
9541 -- Note: not clear why this is needed, how can the original bound
9542 -- be unanalyzed at this point? and if it is, what business do we
9543 -- have messing around with it? and why is the base type of the
9544 -- parent type the right type for the resolution. It probably is
9545 -- not. It is OK for the new bound we are creating, but not for
9546 -- the old one??? Still if it never happens, no problem.
9548 Analyze_And_Resolve (Bound, Base_Type (Par_T));
9550 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
9551 New_Bound := New_Copy (Bound);
9552 Set_Etype (New_Bound, Der_T);
9553 Set_Analyzed (New_Bound);
9555 elsif Is_Entity_Name (Bound) then
9556 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
9558 -- The following is almost certainly wrong. What business do we have
9559 -- relocating a node (Bound) that is presumably still attached to
9560 -- the tree elsewhere???
9563 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
9566 Set_Etype (New_Bound, Der_T);
9568 end Build_Scalar_Bound;
9570 --------------------------------
9571 -- Build_Underlying_Full_View --
9572 --------------------------------
9574 procedure Build_Underlying_Full_View
9579 Loc : constant Source_Ptr := Sloc (N);
9580 Subt : constant Entity_Id :=
9581 Make_Defining_Identifier
9582 (Loc, New_External_Name (Chars (Typ), 'S'));
9589 procedure Set_Discriminant_Name (Id : Node_Id);
9590 -- If the derived type has discriminants, they may rename discriminants
9591 -- of the parent. When building the full view of the parent, we need to
9592 -- recover the names of the original discriminants if the constraint is
9593 -- given by named associations.
9595 ---------------------------
9596 -- Set_Discriminant_Name --
9597 ---------------------------
9599 procedure Set_Discriminant_Name (Id : Node_Id) is
9603 Set_Original_Discriminant (Id, Empty);
9605 if Has_Discriminants (Typ) then
9606 Disc := First_Discriminant (Typ);
9607 while Present (Disc) loop
9608 if Chars (Disc) = Chars (Id)
9609 and then Present (Corresponding_Discriminant (Disc))
9611 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
9613 Next_Discriminant (Disc);
9616 end Set_Discriminant_Name;
9618 -- Start of processing for Build_Underlying_Full_View
9621 if Nkind (N) = N_Full_Type_Declaration then
9622 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
9624 elsif Nkind (N) = N_Subtype_Declaration then
9625 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
9627 elsif Nkind (N) = N_Component_Declaration then
9630 (Constraint (Subtype_Indication (Component_Definition (N))));
9633 raise Program_Error;
9636 C := First (Constraints (Constr));
9637 while Present (C) loop
9638 if Nkind (C) = N_Discriminant_Association then
9639 Id := First (Selector_Names (C));
9640 while Present (Id) loop
9641 Set_Discriminant_Name (Id);
9650 Make_Subtype_Declaration (Loc,
9651 Defining_Identifier => Subt,
9652 Subtype_Indication =>
9653 Make_Subtype_Indication (Loc,
9654 Subtype_Mark => New_Occurrence_Of (Par, Loc),
9655 Constraint => New_Copy_Tree (Constr)));
9657 -- If this is a component subtype for an outer itype, it is not
9658 -- a list member, so simply set the parent link for analysis: if
9659 -- the enclosing type does not need to be in a declarative list,
9660 -- neither do the components.
9662 if Is_List_Member (N)
9663 and then Nkind (N) /= N_Component_Declaration
9665 Insert_Before (N, Indic);
9667 Set_Parent (Indic, Parent (N));
9671 Set_Underlying_Full_View (Typ, Full_View (Subt));
9672 end Build_Underlying_Full_View;
9674 -------------------------------
9675 -- Check_Abstract_Overriding --
9676 -------------------------------
9678 procedure Check_Abstract_Overriding (T : Entity_Id) is
9679 Alias_Subp : Entity_Id;
9685 procedure Check_Pragma_Implemented (Subp : Entity_Id);
9686 -- Ada 2012 (AI05-0030): Subprogram Subp overrides an interface routine
9687 -- which has pragma Implemented already set. Check whether Subp's entity
9688 -- kind conforms to the implementation kind of the overridden routine.
9690 procedure Check_Pragma_Implemented
9692 Iface_Subp : Entity_Id);
9693 -- Ada 2012 (AI05-0030): Subprogram Subp overrides interface routine
9694 -- Iface_Subp and both entities have pragma Implemented already set on
9695 -- them. Check whether the two implementation kinds are conforming.
9697 procedure Inherit_Pragma_Implemented
9699 Iface_Subp : Entity_Id);
9700 -- Ada 2012 (AI05-0030): Interface primitive Subp overrides interface
9701 -- subprogram Iface_Subp which has been marked by pragma Implemented.
9702 -- Propagate the implementation kind of Iface_Subp to Subp.
9704 ------------------------------
9705 -- Check_Pragma_Implemented --
9706 ------------------------------
9708 procedure Check_Pragma_Implemented (Subp : Entity_Id) is
9709 Iface_Alias : constant Entity_Id := Interface_Alias (Subp);
9710 Impl_Kind : constant Name_Id := Implementation_Kind (Iface_Alias);
9711 Subp_Alias : constant Entity_Id := Alias (Subp);
9712 Contr_Typ : Entity_Id;
9713 Impl_Subp : Entity_Id;
9716 -- Subp must have an alias since it is a hidden entity used to link
9717 -- an interface subprogram to its overriding counterpart.
9719 pragma Assert (Present (Subp_Alias));
9721 -- Handle aliases to synchronized wrappers
9723 Impl_Subp := Subp_Alias;
9725 if Is_Primitive_Wrapper (Impl_Subp) then
9726 Impl_Subp := Wrapped_Entity (Impl_Subp);
9729 -- Extract the type of the controlling formal
9731 Contr_Typ := Etype (First_Formal (Subp_Alias));
9733 if Is_Concurrent_Record_Type (Contr_Typ) then
9734 Contr_Typ := Corresponding_Concurrent_Type (Contr_Typ);
9737 -- An interface subprogram whose implementation kind is By_Entry must
9738 -- be implemented by an entry.
9740 if Impl_Kind = Name_By_Entry
9741 and then Ekind (Impl_Subp) /= E_Entry
9743 Error_Msg_Node_2 := Iface_Alias;
9745 ("type & must implement abstract subprogram & with an entry",
9746 Subp_Alias, Contr_Typ);
9748 elsif Impl_Kind = Name_By_Protected_Procedure then
9750 -- An interface subprogram whose implementation kind is By_
9751 -- Protected_Procedure cannot be implemented by a primitive
9752 -- procedure of a task type.
9754 if Ekind (Contr_Typ) /= E_Protected_Type then
9755 Error_Msg_Node_2 := Contr_Typ;
9757 ("interface subprogram & cannot be implemented by a " &
9758 "primitive procedure of task type &", Subp_Alias,
9761 -- An interface subprogram whose implementation kind is By_
9762 -- Protected_Procedure must be implemented by a procedure.
9764 elsif Ekind (Impl_Subp) /= E_Procedure then
9765 Error_Msg_Node_2 := Iface_Alias;
9767 ("type & must implement abstract subprogram & with a " &
9768 "procedure", Subp_Alias, Contr_Typ);
9770 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9771 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9773 Error_Msg_Name_1 := Impl_Kind;
9775 ("overriding operation& must have synchronization%",
9779 -- If primitive has Optional synchronization, overriding operation
9780 -- must match if it has an explicit synchronization..
9782 elsif Present (Get_Rep_Pragma (Impl_Subp, Name_Implemented))
9783 and then Implementation_Kind (Impl_Subp) /= Impl_Kind
9785 Error_Msg_Name_1 := Impl_Kind;
9787 ("overriding operation& must have syncrhonization%",
9790 end Check_Pragma_Implemented;
9792 ------------------------------
9793 -- Check_Pragma_Implemented --
9794 ------------------------------
9796 procedure Check_Pragma_Implemented
9798 Iface_Subp : Entity_Id)
9800 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9801 Subp_Kind : constant Name_Id := Implementation_Kind (Subp);
9804 -- Ada 2012 (AI05-0030): The implementation kinds of an overridden
9805 -- and overriding subprogram are different. In general this is an
9806 -- error except when the implementation kind of the overridden
9807 -- subprograms is By_Any or Optional.
9809 if Iface_Kind /= Subp_Kind
9810 and then Iface_Kind /= Name_By_Any
9811 and then Iface_Kind /= Name_Optional
9813 if Iface_Kind = Name_By_Entry then
9815 ("incompatible implementation kind, overridden subprogram " &
9816 "is marked By_Entry", Subp);
9819 ("incompatible implementation kind, overridden subprogram " &
9820 "is marked By_Protected_Procedure", Subp);
9823 end Check_Pragma_Implemented;
9825 --------------------------------
9826 -- Inherit_Pragma_Implemented --
9827 --------------------------------
9829 procedure Inherit_Pragma_Implemented
9831 Iface_Subp : Entity_Id)
9833 Iface_Kind : constant Name_Id := Implementation_Kind (Iface_Subp);
9834 Loc : constant Source_Ptr := Sloc (Subp);
9835 Impl_Prag : Node_Id;
9838 -- Since the implementation kind is stored as a representation item
9839 -- rather than a flag, create a pragma node.
9843 Chars => Name_Implemented,
9844 Pragma_Argument_Associations => New_List (
9845 Make_Pragma_Argument_Association (Loc,
9846 Expression => New_Occurrence_Of (Subp, Loc)),
9848 Make_Pragma_Argument_Association (Loc,
9849 Expression => Make_Identifier (Loc, Iface_Kind))));
9851 -- The pragma doesn't need to be analyzed because it is internally
9852 -- built. It is safe to directly register it as a rep item since we
9853 -- are only interested in the characters of the implementation kind.
9855 Record_Rep_Item (Subp, Impl_Prag);
9856 end Inherit_Pragma_Implemented;
9858 -- Start of processing for Check_Abstract_Overriding
9861 Op_List := Primitive_Operations (T);
9863 -- Loop to check primitive operations
9865 Elmt := First_Elmt (Op_List);
9866 while Present (Elmt) loop
9867 Subp := Node (Elmt);
9868 Alias_Subp := Alias (Subp);
9870 -- Inherited subprograms are identified by the fact that they do not
9871 -- come from source, and the associated source location is the
9872 -- location of the first subtype of the derived type.
9874 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
9875 -- subprograms that "require overriding".
9877 -- Special exception, do not complain about failure to override the
9878 -- stream routines _Input and _Output, as well as the primitive
9879 -- operations used in dispatching selects since we always provide
9880 -- automatic overridings for these subprograms.
9882 -- Also ignore this rule for convention CIL since .NET libraries
9883 -- do bizarre things with interfaces???
9885 -- The partial view of T may have been a private extension, for
9886 -- which inherited functions dispatching on result are abstract.
9887 -- If the full view is a null extension, there is no need for
9888 -- overriding in Ada 2005, but wrappers need to be built for them
9889 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
9891 if Is_Null_Extension (T)
9892 and then Has_Controlling_Result (Subp)
9893 and then Ada_Version >= Ada_2005
9894 and then Present (Alias_Subp)
9895 and then not Comes_From_Source (Subp)
9896 and then not Is_Abstract_Subprogram (Alias_Subp)
9897 and then not Is_Access_Type (Etype (Subp))
9901 -- Ada 2005 (AI-251): Internal entities of interfaces need no
9902 -- processing because this check is done with the aliased
9905 elsif Present (Interface_Alias (Subp)) then
9908 elsif (Is_Abstract_Subprogram (Subp)
9909 or else Requires_Overriding (Subp)
9911 (Has_Controlling_Result (Subp)
9912 and then Present (Alias_Subp)
9913 and then not Comes_From_Source (Subp)
9914 and then Sloc (Subp) = Sloc (First_Subtype (T))))
9915 and then not Is_TSS (Subp, TSS_Stream_Input)
9916 and then not Is_TSS (Subp, TSS_Stream_Output)
9917 and then not Is_Abstract_Type (T)
9918 and then Convention (T) /= Convention_CIL
9919 and then not Is_Predefined_Interface_Primitive (Subp)
9921 -- Ada 2005 (AI-251): Do not consider hidden entities associated
9922 -- with abstract interface types because the check will be done
9923 -- with the aliased entity (otherwise we generate a duplicated
9926 and then not Present (Interface_Alias (Subp))
9928 if Present (Alias_Subp) then
9930 -- Only perform the check for a derived subprogram when the
9931 -- type has an explicit record extension. This avoids incorrect
9932 -- flagging of abstract subprograms for the case of a type
9933 -- without an extension that is derived from a formal type
9934 -- with a tagged actual (can occur within a private part).
9936 -- Ada 2005 (AI-391): In the case of an inherited function with
9937 -- a controlling result of the type, the rule does not apply if
9938 -- the type is a null extension (unless the parent function
9939 -- itself is abstract, in which case the function must still be
9940 -- be overridden). The expander will generate an overriding
9941 -- wrapper function calling the parent subprogram (see
9942 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
9944 Type_Def := Type_Definition (Parent (T));
9946 if Nkind (Type_Def) = N_Derived_Type_Definition
9947 and then Present (Record_Extension_Part (Type_Def))
9949 (Ada_Version < Ada_2005
9950 or else not Is_Null_Extension (T)
9951 or else Ekind (Subp) = E_Procedure
9952 or else not Has_Controlling_Result (Subp)
9953 or else Is_Abstract_Subprogram (Alias_Subp)
9954 or else Requires_Overriding (Subp)
9955 or else Is_Access_Type (Etype (Subp)))
9957 -- Avoid reporting error in case of abstract predefined
9958 -- primitive inherited from interface type because the
9959 -- body of internally generated predefined primitives
9960 -- of tagged types are generated later by Freeze_Type
9962 if Is_Interface (Root_Type (T))
9963 and then Is_Abstract_Subprogram (Subp)
9964 and then Is_Predefined_Dispatching_Operation (Subp)
9965 and then not Comes_From_Source (Ultimate_Alias (Subp))
9969 -- A null extension is not obliged to override an inherited
9970 -- procedure subject to pragma Extensions_Visible with value
9971 -- False and at least one controlling OUT parameter
9972 -- (SPARK RM 6.1.7(6)).
9974 elsif Is_Null_Extension (T)
9975 and then Is_EVF_Procedure (Subp)
9981 ("type must be declared abstract or & overridden",
9984 -- Traverse the whole chain of aliased subprograms to
9985 -- complete the error notification. This is especially
9986 -- useful for traceability of the chain of entities when
9987 -- the subprogram corresponds with an interface
9988 -- subprogram (which may be defined in another package).
9990 if Present (Alias_Subp) then
9996 while Present (Alias (E)) loop
9998 -- Avoid reporting redundant errors on entities
9999 -- inherited from interfaces
10001 if Sloc (E) /= Sloc (T) then
10002 Error_Msg_Sloc := Sloc (E);
10004 ("\& has been inherited #", T, Subp);
10010 Error_Msg_Sloc := Sloc (E);
10012 -- AI05-0068: report if there is an overriding
10013 -- non-abstract subprogram that is invisible.
10016 and then not Is_Abstract_Subprogram (E)
10019 ("\& subprogram# is not visible",
10022 -- Clarify the case where a non-null extension must
10023 -- override inherited procedure subject to pragma
10024 -- Extensions_Visible with value False and at least
10025 -- one controlling OUT param.
10027 elsif Is_EVF_Procedure (E) then
10029 ("\& # is subject to Extensions_Visible False",
10034 ("\& has been inherited from subprogram #",
10041 -- Ada 2005 (AI-345): Protected or task type implementing
10042 -- abstract interfaces.
10044 elsif Is_Concurrent_Record_Type (T)
10045 and then Present (Interfaces (T))
10047 -- If an inherited subprogram is implemented by a protected
10048 -- procedure or an entry, then the first parameter of the
10049 -- inherited subprogram shall be of mode OUT or IN OUT, or
10050 -- an access-to-variable parameter (RM 9.4(11.9/3))
10052 if Is_Protected_Type (Corresponding_Concurrent_Type (T))
10053 and then Ekind (First_Formal (Subp)) = E_In_Parameter
10054 and then Ekind (Subp) /= E_Function
10055 and then not Is_Predefined_Dispatching_Operation (Subp)
10057 Error_Msg_PT (T, Subp);
10059 -- Some other kind of overriding failure
10063 ("interface subprogram & must be overridden",
10066 -- Examine primitive operations of synchronized type,
10067 -- to find homonyms that have the wrong profile.
10074 First_Entity (Corresponding_Concurrent_Type (T));
10075 while Present (Prim) loop
10076 if Chars (Prim) = Chars (Subp) then
10078 ("profile is not type conformant with "
10079 & "prefixed view profile of "
10080 & "inherited operation&", Prim, Subp);
10083 Next_Entity (Prim);
10090 Error_Msg_Node_2 := T;
10092 ("abstract subprogram& not allowed for type&", Subp);
10094 -- Also post unconditional warning on the type (unconditional
10095 -- so that if there are more than one of these cases, we get
10096 -- them all, and not just the first one).
10098 Error_Msg_Node_2 := Subp;
10099 Error_Msg_N ("nonabstract type& has abstract subprogram&!", T);
10102 -- A subprogram subject to pragma Extensions_Visible with value
10103 -- "True" cannot override a subprogram subject to the same pragma
10104 -- with value "False" (SPARK RM 6.1.7(5)).
10106 elsif Extensions_Visible_Status (Subp) = Extensions_Visible_True
10107 and then Present (Overridden_Operation (Subp))
10108 and then Extensions_Visible_Status (Overridden_Operation (Subp)) =
10109 Extensions_Visible_False
10111 Error_Msg_Sloc := Sloc (Overridden_Operation (Subp));
10113 ("subprogram & with Extensions_Visible True cannot override "
10114 & "subprogram # with Extensions_Visible False", Subp);
10117 -- Ada 2012 (AI05-0030): Perform checks related to pragma Implemented
10119 -- Subp is an expander-generated procedure which maps an interface
10120 -- alias to a protected wrapper. The interface alias is flagged by
10121 -- pragma Implemented. Ensure that Subp is a procedure when the
10122 -- implementation kind is By_Protected_Procedure or an entry when
10125 if Ada_Version >= Ada_2012
10126 and then Is_Hidden (Subp)
10127 and then Present (Interface_Alias (Subp))
10128 and then Has_Rep_Pragma (Interface_Alias (Subp), Name_Implemented)
10130 Check_Pragma_Implemented (Subp);
10133 -- Subp is an interface primitive which overrides another interface
10134 -- primitive marked with pragma Implemented.
10136 if Ada_Version >= Ada_2012
10137 and then Present (Overridden_Operation (Subp))
10138 and then Has_Rep_Pragma
10139 (Overridden_Operation (Subp), Name_Implemented)
10141 -- If the overriding routine is also marked by Implemented, check
10142 -- that the two implementation kinds are conforming.
10144 if Has_Rep_Pragma (Subp, Name_Implemented) then
10145 Check_Pragma_Implemented
10147 Iface_Subp => Overridden_Operation (Subp));
10149 -- Otherwise the overriding routine inherits the implementation
10150 -- kind from the overridden subprogram.
10153 Inherit_Pragma_Implemented
10155 Iface_Subp => Overridden_Operation (Subp));
10159 -- If the operation is a wrapper for a synchronized primitive, it
10160 -- may be called indirectly through a dispatching select. We assume
10161 -- that it will be referenced elsewhere indirectly, and suppress
10162 -- warnings about an unused entity.
10164 if Is_Primitive_Wrapper (Subp)
10165 and then Present (Wrapped_Entity (Subp))
10167 Set_Referenced (Wrapped_Entity (Subp));
10172 end Check_Abstract_Overriding;
10174 ------------------------------------------------
10175 -- Check_Access_Discriminant_Requires_Limited --
10176 ------------------------------------------------
10178 procedure Check_Access_Discriminant_Requires_Limited
10183 -- A discriminant_specification for an access discriminant shall appear
10184 -- only in the declaration for a task or protected type, or for a type
10185 -- with the reserved word 'limited' in its definition or in one of its
10186 -- ancestors (RM 3.7(10)).
10188 -- AI-0063: The proper condition is that type must be immutably limited,
10189 -- or else be a partial view.
10191 if Nkind (Discriminant_Type (D)) = N_Access_Definition then
10192 if Is_Limited_View (Current_Scope)
10194 (Nkind (Parent (Current_Scope)) = N_Private_Type_Declaration
10195 and then Limited_Present (Parent (Current_Scope)))
10201 ("access discriminants allowed only for limited types", Loc);
10204 end Check_Access_Discriminant_Requires_Limited;
10206 -----------------------------------
10207 -- Check_Aliased_Component_Types --
10208 -----------------------------------
10210 procedure Check_Aliased_Component_Types (T : Entity_Id) is
10214 -- ??? Also need to check components of record extensions, but not
10215 -- components of protected types (which are always limited).
10217 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
10218 -- types to be unconstrained. This is safe because it is illegal to
10219 -- create access subtypes to such types with explicit discriminant
10222 if not Is_Limited_Type (T) then
10223 if Ekind (T) = E_Record_Type then
10224 C := First_Component (T);
10225 while Present (C) loop
10227 and then Has_Discriminants (Etype (C))
10228 and then not Is_Constrained (Etype (C))
10229 and then not In_Instance_Body
10230 and then Ada_Version < Ada_2005
10233 ("aliased component must be constrained (RM 3.6(11))",
10237 Next_Component (C);
10240 elsif Ekind (T) = E_Array_Type then
10241 if Has_Aliased_Components (T)
10242 and then Has_Discriminants (Component_Type (T))
10243 and then not Is_Constrained (Component_Type (T))
10244 and then not In_Instance_Body
10245 and then Ada_Version < Ada_2005
10248 ("aliased component type must be constrained (RM 3.6(11))",
10253 end Check_Aliased_Component_Types;
10255 ---------------------------------------
10256 -- Check_Anonymous_Access_Components --
10257 ---------------------------------------
10259 procedure Check_Anonymous_Access_Components
10260 (Typ_Decl : Node_Id;
10263 Comp_List : Node_Id)
10265 Loc : constant Source_Ptr := Sloc (Typ_Decl);
10266 Anon_Access : Entity_Id;
10269 Comp_Def : Node_Id;
10271 Type_Def : Node_Id;
10273 procedure Build_Incomplete_Type_Declaration;
10274 -- If the record type contains components that include an access to the
10275 -- current record, then create an incomplete type declaration for the
10276 -- record, to be used as the designated type of the anonymous access.
10277 -- This is done only once, and only if there is no previous partial
10278 -- view of the type.
10280 function Designates_T (Subt : Node_Id) return Boolean;
10281 -- Check whether a node designates the enclosing record type, or 'Class
10284 function Mentions_T (Acc_Def : Node_Id) return Boolean;
10285 -- Check whether an access definition includes a reference to
10286 -- the enclosing record type. The reference can be a subtype mark
10287 -- in the access definition itself, a 'Class attribute reference, or
10288 -- recursively a reference appearing in a parameter specification
10289 -- or result definition of an access_to_subprogram definition.
10291 --------------------------------------
10292 -- Build_Incomplete_Type_Declaration --
10293 --------------------------------------
10295 procedure Build_Incomplete_Type_Declaration is
10300 -- Is_Tagged indicates whether the type is tagged. It is tagged if
10301 -- it's "is new ... with record" or else "is tagged record ...".
10303 Is_Tagged : constant Boolean :=
10304 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
10306 Present (Record_Extension_Part (Type_Definition (Typ_Decl))))
10308 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
10309 and then Tagged_Present (Type_Definition (Typ_Decl)));
10312 -- If there is a previous partial view, no need to create a new one
10313 -- If the partial view, given by Prev, is incomplete, If Prev is
10314 -- a private declaration, full declaration is flagged accordingly.
10316 if Prev /= Typ then
10318 Make_Class_Wide_Type (Prev);
10319 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
10320 Set_Etype (Class_Wide_Type (Typ), Typ);
10325 elsif Has_Private_Declaration (Typ) then
10327 -- If we refer to T'Class inside T, and T is the completion of a
10328 -- private type, then make sure the class-wide type exists.
10331 Make_Class_Wide_Type (Typ);
10336 -- If there was a previous anonymous access type, the incomplete
10337 -- type declaration will have been created already.
10339 elsif Present (Current_Entity (Typ))
10340 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
10341 and then Full_View (Current_Entity (Typ)) = Typ
10344 and then Comes_From_Source (Current_Entity (Typ))
10345 and then not Is_Tagged_Type (Current_Entity (Typ))
10347 Make_Class_Wide_Type (Typ);
10349 ("incomplete view of tagged type should be declared tagged??",
10350 Parent (Current_Entity (Typ)));
10355 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
10356 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
10358 -- Type has already been inserted into the current scope. Remove
10359 -- it, and add incomplete declaration for type, so that subsequent
10360 -- anonymous access types can use it. The entity is unchained from
10361 -- the homonym list and from immediate visibility. After analysis,
10362 -- the entity in the incomplete declaration becomes immediately
10363 -- visible in the record declaration that follows.
10365 H := Current_Entity (Typ);
10368 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
10371 and then Homonym (H) /= Typ
10373 H := Homonym (Typ);
10376 Set_Homonym (H, Homonym (Typ));
10379 Insert_Before (Typ_Decl, Decl);
10381 Set_Full_View (Inc_T, Typ);
10385 -- Create a common class-wide type for both views, and set the
10386 -- Etype of the class-wide type to the full view.
10388 Make_Class_Wide_Type (Inc_T);
10389 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
10390 Set_Etype (Class_Wide_Type (Typ), Typ);
10393 end Build_Incomplete_Type_Declaration;
10399 function Designates_T (Subt : Node_Id) return Boolean is
10400 Type_Id : constant Name_Id := Chars (Typ);
10402 function Names_T (Nam : Node_Id) return Boolean;
10403 -- The record type has not been introduced in the current scope
10404 -- yet, so we must examine the name of the type itself, either
10405 -- an identifier T, or an expanded name of the form P.T, where
10406 -- P denotes the current scope.
10412 function Names_T (Nam : Node_Id) return Boolean is
10414 if Nkind (Nam) = N_Identifier then
10415 return Chars (Nam) = Type_Id;
10417 elsif Nkind (Nam) = N_Selected_Component then
10418 if Chars (Selector_Name (Nam)) = Type_Id then
10419 if Nkind (Prefix (Nam)) = N_Identifier then
10420 return Chars (Prefix (Nam)) = Chars (Current_Scope);
10422 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
10423 return Chars (Selector_Name (Prefix (Nam))) =
10424 Chars (Current_Scope);
10438 -- Start of processing for Designates_T
10441 if Nkind (Subt) = N_Identifier then
10442 return Chars (Subt) = Type_Id;
10444 -- Reference can be through an expanded name which has not been
10445 -- analyzed yet, and which designates enclosing scopes.
10447 elsif Nkind (Subt) = N_Selected_Component then
10448 if Names_T (Subt) then
10451 -- Otherwise it must denote an entity that is already visible.
10452 -- The access definition may name a subtype of the enclosing
10453 -- type, if there is a previous incomplete declaration for it.
10456 Find_Selected_Component (Subt);
10458 Is_Entity_Name (Subt)
10459 and then Scope (Entity (Subt)) = Current_Scope
10461 (Chars (Base_Type (Entity (Subt))) = Type_Id
10463 (Is_Class_Wide_Type (Entity (Subt))
10465 Chars (Etype (Base_Type (Entity (Subt)))) =
10469 -- A reference to the current type may appear as the prefix of
10470 -- a 'Class attribute.
10472 elsif Nkind (Subt) = N_Attribute_Reference
10473 and then Attribute_Name (Subt) = Name_Class
10475 return Names_T (Prefix (Subt));
10486 function Mentions_T (Acc_Def : Node_Id) return Boolean is
10487 Param_Spec : Node_Id;
10489 Acc_Subprg : constant Node_Id :=
10490 Access_To_Subprogram_Definition (Acc_Def);
10493 if No (Acc_Subprg) then
10494 return Designates_T (Subtype_Mark (Acc_Def));
10497 -- Component is an access_to_subprogram: examine its formals,
10498 -- and result definition in the case of an access_to_function.
10500 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
10501 while Present (Param_Spec) loop
10502 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
10503 and then Mentions_T (Parameter_Type (Param_Spec))
10507 elsif Designates_T (Parameter_Type (Param_Spec)) then
10514 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
10515 if Nkind (Result_Definition (Acc_Subprg)) =
10516 N_Access_Definition
10518 return Mentions_T (Result_Definition (Acc_Subprg));
10520 return Designates_T (Result_Definition (Acc_Subprg));
10527 -- Start of processing for Check_Anonymous_Access_Components
10530 if No (Comp_List) then
10534 Comp := First (Component_Items (Comp_List));
10535 while Present (Comp) loop
10536 if Nkind (Comp) = N_Component_Declaration
10538 (Access_Definition (Component_Definition (Comp)))
10540 Mentions_T (Access_Definition (Component_Definition (Comp)))
10542 Comp_Def := Component_Definition (Comp);
10544 Access_To_Subprogram_Definition (Access_Definition (Comp_Def));
10546 Build_Incomplete_Type_Declaration;
10547 Anon_Access := Make_Temporary (Loc, 'S');
10549 -- Create a declaration for the anonymous access type: either
10550 -- an access_to_object or an access_to_subprogram.
10552 if Present (Acc_Def) then
10553 if Nkind (Acc_Def) = N_Access_Function_Definition then
10555 Make_Access_Function_Definition (Loc,
10556 Parameter_Specifications =>
10557 Parameter_Specifications (Acc_Def),
10558 Result_Definition => Result_Definition (Acc_Def));
10561 Make_Access_Procedure_Definition (Loc,
10562 Parameter_Specifications =>
10563 Parameter_Specifications (Acc_Def));
10568 Make_Access_To_Object_Definition (Loc,
10569 Subtype_Indication =>
10571 (Subtype_Mark (Access_Definition (Comp_Def))));
10573 Set_Constant_Present
10574 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
10576 (Type_Def, All_Present (Access_Definition (Comp_Def)));
10579 Set_Null_Exclusion_Present
10581 Null_Exclusion_Present (Access_Definition (Comp_Def)));
10584 Make_Full_Type_Declaration (Loc,
10585 Defining_Identifier => Anon_Access,
10586 Type_Definition => Type_Def);
10588 Insert_Before (Typ_Decl, Decl);
10591 -- If an access to subprogram, create the extra formals
10593 if Present (Acc_Def) then
10594 Create_Extra_Formals (Designated_Type (Anon_Access));
10596 -- If an access to object, preserve entity of designated type,
10597 -- for ASIS use, before rewriting the component definition.
10604 Desig := Entity (Subtype_Indication (Type_Def));
10606 -- If the access definition is to the current record,
10607 -- the visible entity at this point is an incomplete
10608 -- type. Retrieve the full view to simplify ASIS queries
10610 if Ekind (Desig) = E_Incomplete_Type then
10611 Desig := Full_View (Desig);
10615 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
10620 Make_Component_Definition (Loc,
10621 Subtype_Indication =>
10622 New_Occurrence_Of (Anon_Access, Loc)));
10624 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
10625 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
10627 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
10630 Set_Is_Local_Anonymous_Access (Anon_Access);
10636 if Present (Variant_Part (Comp_List)) then
10640 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
10641 while Present (V) loop
10642 Check_Anonymous_Access_Components
10643 (Typ_Decl, Typ, Prev, Component_List (V));
10644 Next_Non_Pragma (V);
10648 end Check_Anonymous_Access_Components;
10650 ----------------------
10651 -- Check_Completion --
10652 ----------------------
10654 procedure Check_Completion (Body_Id : Node_Id := Empty) is
10657 procedure Post_Error;
10658 -- Post error message for lack of completion for entity E
10664 procedure Post_Error is
10666 procedure Missing_Body;
10667 -- Output missing body message
10673 procedure Missing_Body is
10675 -- Spec is in same unit, so we can post on spec
10677 if In_Same_Source_Unit (Body_Id, E) then
10678 Error_Msg_N ("missing body for &", E);
10680 -- Spec is in a separate unit, so we have to post on the body
10683 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
10687 -- Start of processing for Post_Error
10690 if not Comes_From_Source (E) then
10692 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
10694 -- It may be an anonymous protected type created for a
10695 -- single variable. Post error on variable, if present.
10701 Var := First_Entity (Current_Scope);
10702 while Present (Var) loop
10703 exit when Etype (Var) = E
10704 and then Comes_From_Source (Var);
10709 if Present (Var) then
10716 -- If a generated entity has no completion, then either previous
10717 -- semantic errors have disabled the expansion phase, or else we had
10718 -- missing subunits, or else we are compiling without expansion,
10719 -- or else something is very wrong.
10721 if not Comes_From_Source (E) then
10723 (Serious_Errors_Detected > 0
10724 or else Configurable_Run_Time_Violations > 0
10725 or else Subunits_Missing
10726 or else not Expander_Active);
10729 -- Here for source entity
10732 -- Here if no body to post the error message, so we post the error
10733 -- on the declaration that has no completion. This is not really
10734 -- the right place to post it, think about this later ???
10736 if No (Body_Id) then
10737 if Is_Type (E) then
10739 ("missing full declaration for }", Parent (E), E);
10741 Error_Msg_NE ("missing body for &", Parent (E), E);
10744 -- Package body has no completion for a declaration that appears
10745 -- in the corresponding spec. Post error on the body, with a
10746 -- reference to the non-completed declaration.
10749 Error_Msg_Sloc := Sloc (E);
10751 if Is_Type (E) then
10752 Error_Msg_NE ("missing full declaration for }!", Body_Id, E);
10754 elsif Is_Overloadable (E)
10755 and then Current_Entity_In_Scope (E) /= E
10757 -- It may be that the completion is mistyped and appears as
10758 -- a distinct overloading of the entity.
10761 Candidate : constant Entity_Id :=
10762 Current_Entity_In_Scope (E);
10763 Decl : constant Node_Id :=
10764 Unit_Declaration_Node (Candidate);
10767 if Is_Overloadable (Candidate)
10768 and then Ekind (Candidate) = Ekind (E)
10769 and then Nkind (Decl) = N_Subprogram_Body
10770 and then Acts_As_Spec (Decl)
10772 Check_Type_Conformant (Candidate, E);
10788 Pack_Id : constant Entity_Id := Current_Scope;
10790 -- Start of processing for Check_Completion
10793 E := First_Entity (Pack_Id);
10794 while Present (E) loop
10795 if Is_Intrinsic_Subprogram (E) then
10798 -- A Ghost entity declared in a non-Ghost package does not force the
10799 -- need for a body (SPARK RM 6.9(11)).
10801 elsif not Is_Ghost_Entity (Pack_Id) and then Is_Ghost_Entity (E) then
10804 -- The following situation requires special handling: a child unit
10805 -- that appears in the context clause of the body of its parent:
10807 -- procedure Parent.Child (...);
10809 -- with Parent.Child;
10810 -- package body Parent is
10812 -- Here Parent.Child appears as a local entity, but should not be
10813 -- flagged as requiring completion, because it is a compilation
10816 -- Ignore missing completion for a subprogram that does not come from
10817 -- source (including the _Call primitive operation of RAS types,
10818 -- which has to have the flag Comes_From_Source for other purposes):
10819 -- we assume that the expander will provide the missing completion.
10820 -- In case of previous errors, other expansion actions that provide
10821 -- bodies for null procedures with not be invoked, so inhibit message
10824 -- Note that E_Operator is not in the list that follows, because
10825 -- this kind is reserved for predefined operators, that are
10826 -- intrinsic and do not need completion.
10828 elsif Ekind_In (E, E_Function,
10830 E_Generic_Function,
10831 E_Generic_Procedure)
10833 if Has_Completion (E) then
10836 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
10839 elsif Is_Subprogram (E)
10840 and then (not Comes_From_Source (E)
10841 or else Chars (E) = Name_uCall)
10846 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
10850 elsif Nkind (Parent (E)) = N_Procedure_Specification
10851 and then Null_Present (Parent (E))
10852 and then Serious_Errors_Detected > 0
10860 elsif Is_Entry (E) then
10861 if not Has_Completion (E) and then
10862 (Ekind (Scope (E)) = E_Protected_Object
10863 or else Ekind (Scope (E)) = E_Protected_Type)
10868 elsif Is_Package_Or_Generic_Package (E) then
10869 if Unit_Requires_Body (E) then
10870 if not Has_Completion (E)
10871 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
10877 elsif not Is_Child_Unit (E) then
10878 May_Need_Implicit_Body (E);
10881 -- A formal incomplete type (Ada 2012) does not require a completion;
10882 -- other incomplete type declarations do.
10884 elsif Ekind (E) = E_Incomplete_Type
10885 and then No (Underlying_Type (E))
10886 and then not Is_Generic_Type (E)
10890 elsif Ekind_In (E, E_Task_Type, E_Protected_Type)
10891 and then not Has_Completion (E)
10895 -- A single task declared in the current scope is a constant, verify
10896 -- that the body of its anonymous type is in the same scope. If the
10897 -- task is defined elsewhere, this may be a renaming declaration for
10898 -- which no completion is needed.
10900 elsif Ekind (E) = E_Constant
10901 and then Ekind (Etype (E)) = E_Task_Type
10902 and then not Has_Completion (Etype (E))
10903 and then Scope (Etype (E)) = Current_Scope
10907 elsif Ekind (E) = E_Protected_Object
10908 and then not Has_Completion (Etype (E))
10912 elsif Ekind (E) = E_Record_Type then
10913 if Is_Tagged_Type (E) then
10914 Check_Abstract_Overriding (E);
10915 Check_Conventions (E);
10918 Check_Aliased_Component_Types (E);
10920 elsif Ekind (E) = E_Array_Type then
10921 Check_Aliased_Component_Types (E);
10927 end Check_Completion;
10929 ------------------------------------
10930 -- Check_CPP_Type_Has_No_Defaults --
10931 ------------------------------------
10933 procedure Check_CPP_Type_Has_No_Defaults (T : Entity_Id) is
10934 Tdef : constant Node_Id := Type_Definition (Declaration_Node (T));
10939 -- Obtain the component list
10941 if Nkind (Tdef) = N_Record_Definition then
10942 Clist := Component_List (Tdef);
10943 else pragma Assert (Nkind (Tdef) = N_Derived_Type_Definition);
10944 Clist := Component_List (Record_Extension_Part (Tdef));
10947 -- Check all components to ensure no default expressions
10949 if Present (Clist) then
10950 Comp := First (Component_Items (Clist));
10951 while Present (Comp) loop
10952 if Present (Expression (Comp)) then
10954 ("component of imported 'C'P'P type cannot have "
10955 & "default expression", Expression (Comp));
10961 end Check_CPP_Type_Has_No_Defaults;
10963 ----------------------------
10964 -- Check_Delta_Expression --
10965 ----------------------------
10967 procedure Check_Delta_Expression (E : Node_Id) is
10969 if not (Is_Real_Type (Etype (E))) then
10970 Wrong_Type (E, Any_Real);
10972 elsif not Is_OK_Static_Expression (E) then
10973 Flag_Non_Static_Expr
10974 ("non-static expression used for delta value!", E);
10976 elsif not UR_Is_Positive (Expr_Value_R (E)) then
10977 Error_Msg_N ("delta expression must be positive", E);
10983 -- If any of above errors occurred, then replace the incorrect
10984 -- expression by the real 0.1, which should prevent further errors.
10987 Make_Real_Literal (Sloc (E), Ureal_Tenth));
10988 Analyze_And_Resolve (E, Standard_Float);
10989 end Check_Delta_Expression;
10991 -----------------------------
10992 -- Check_Digits_Expression --
10993 -----------------------------
10995 procedure Check_Digits_Expression (E : Node_Id) is
10997 if not (Is_Integer_Type (Etype (E))) then
10998 Wrong_Type (E, Any_Integer);
11000 elsif not Is_OK_Static_Expression (E) then
11001 Flag_Non_Static_Expr
11002 ("non-static expression used for digits value!", E);
11004 elsif Expr_Value (E) <= 0 then
11005 Error_Msg_N ("digits value must be greater than zero", E);
11011 -- If any of above errors occurred, then replace the incorrect
11012 -- expression by the integer 1, which should prevent further errors.
11014 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
11015 Analyze_And_Resolve (E, Standard_Integer);
11017 end Check_Digits_Expression;
11019 --------------------------
11020 -- Check_Initialization --
11021 --------------------------
11023 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
11025 -- Special processing for limited types
11027 if Is_Limited_Type (T)
11028 and then not In_Instance
11029 and then not In_Inlined_Body
11031 if not OK_For_Limited_Init (T, Exp) then
11033 -- In GNAT mode, this is just a warning, to allow it to be evilly
11034 -- turned off. Otherwise it is a real error.
11038 ("??cannot initialize entities of limited type!", Exp);
11040 elsif Ada_Version < Ada_2005 then
11042 -- The side effect removal machinery may generate illegal Ada
11043 -- code to avoid the usage of access types and 'reference in
11044 -- SPARK mode. Since this is legal code with respect to theorem
11045 -- proving, do not emit the error.
11048 and then Nkind (Exp) = N_Function_Call
11049 and then Nkind (Parent (Exp)) = N_Object_Declaration
11050 and then not Comes_From_Source
11051 (Defining_Identifier (Parent (Exp)))
11057 ("cannot initialize entities of limited type", Exp);
11058 Explain_Limited_Type (T, Exp);
11062 -- Specialize error message according to kind of illegal
11063 -- initial expression.
11065 if Nkind (Exp) = N_Type_Conversion
11066 and then Nkind (Expression (Exp)) = N_Function_Call
11069 ("illegal context for call"
11070 & " to function with limited result", Exp);
11074 ("initialization of limited object requires aggregate "
11075 & "or function call", Exp);
11081 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag gets
11082 -- set unless we can be sure that no range check is required.
11084 if (GNATprove_Mode or not Expander_Active)
11085 and then Is_Scalar_Type (T)
11086 and then not Is_In_Range (Exp, T, Assume_Valid => True)
11088 Set_Do_Range_Check (Exp);
11090 end Check_Initialization;
11092 ----------------------
11093 -- Check_Interfaces --
11094 ----------------------
11096 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
11097 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
11100 Iface_Def : Node_Id;
11101 Iface_Typ : Entity_Id;
11102 Parent_Node : Node_Id;
11104 Is_Task : Boolean := False;
11105 -- Set True if parent type or any progenitor is a task interface
11107 Is_Protected : Boolean := False;
11108 -- Set True if parent type or any progenitor is a protected interface
11110 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
11111 -- Check that a progenitor is compatible with declaration. If an error
11112 -- message is output, it is posted on Error_Node.
11118 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
11119 Iface_Id : constant Entity_Id :=
11120 Defining_Identifier (Parent (Iface_Def));
11121 Type_Def : Node_Id;
11124 if Nkind (N) = N_Private_Extension_Declaration then
11127 Type_Def := Type_Definition (N);
11130 if Is_Task_Interface (Iface_Id) then
11133 elsif Is_Protected_Interface (Iface_Id) then
11134 Is_Protected := True;
11137 if Is_Synchronized_Interface (Iface_Id) then
11139 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
11140 -- extension derived from a synchronized interface must explicitly
11141 -- be declared synchronized, because the full view will be a
11142 -- synchronized type.
11144 if Nkind (N) = N_Private_Extension_Declaration then
11145 if not Synchronized_Present (N) then
11147 ("private extension of& must be explicitly synchronized",
11151 -- However, by 3.9.4(16/2), a full type that is a record extension
11152 -- is never allowed to derive from a synchronized interface (note
11153 -- that interfaces must be excluded from this check, because those
11154 -- are represented by derived type definitions in some cases).
11156 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11157 and then not Interface_Present (Type_Definition (N))
11159 Error_Msg_N ("record extension cannot derive from synchronized "
11160 & "interface", Error_Node);
11164 -- Check that the characteristics of the progenitor are compatible
11165 -- with the explicit qualifier in the declaration.
11166 -- The check only applies to qualifiers that come from source.
11167 -- Limited_Present also appears in the declaration of corresponding
11168 -- records, and the check does not apply to them.
11170 if Limited_Present (Type_Def)
11172 Is_Concurrent_Record_Type (Defining_Identifier (N))
11174 if Is_Limited_Interface (Parent_Type)
11175 and then not Is_Limited_Interface (Iface_Id)
11178 ("progenitor & must be limited interface",
11179 Error_Node, Iface_Id);
11182 (Task_Present (Iface_Def)
11183 or else Protected_Present (Iface_Def)
11184 or else Synchronized_Present (Iface_Def))
11185 and then Nkind (N) /= N_Private_Extension_Declaration
11186 and then not Error_Posted (N)
11189 ("progenitor & must be limited interface",
11190 Error_Node, Iface_Id);
11193 -- Protected interfaces can only inherit from limited, synchronized
11194 -- or protected interfaces.
11196 elsif Nkind (N) = N_Full_Type_Declaration
11197 and then Protected_Present (Type_Def)
11199 if Limited_Present (Iface_Def)
11200 or else Synchronized_Present (Iface_Def)
11201 or else Protected_Present (Iface_Def)
11205 elsif Task_Present (Iface_Def) then
11206 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11207 & "from task interface", Error_Node);
11210 Error_Msg_N ("(Ada 2005) protected interface cannot inherit "
11211 & "from non-limited interface", Error_Node);
11214 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
11215 -- limited and synchronized.
11217 elsif Synchronized_Present (Type_Def) then
11218 if Limited_Present (Iface_Def)
11219 or else Synchronized_Present (Iface_Def)
11223 elsif Protected_Present (Iface_Def)
11224 and then Nkind (N) /= N_Private_Extension_Declaration
11226 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11227 & "from protected interface", Error_Node);
11229 elsif Task_Present (Iface_Def)
11230 and then Nkind (N) /= N_Private_Extension_Declaration
11232 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11233 & "from task interface", Error_Node);
11235 elsif not Is_Limited_Interface (Iface_Id) then
11236 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit "
11237 & "from non-limited interface", Error_Node);
11240 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
11241 -- synchronized or task interfaces.
11243 elsif Nkind (N) = N_Full_Type_Declaration
11244 and then Task_Present (Type_Def)
11246 if Limited_Present (Iface_Def)
11247 or else Synchronized_Present (Iface_Def)
11248 or else Task_Present (Iface_Def)
11252 elsif Protected_Present (Iface_Def) then
11253 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11254 & "protected interface", Error_Node);
11257 Error_Msg_N ("(Ada 2005) task interface cannot inherit from "
11258 & "non-limited interface", Error_Node);
11263 -- Start of processing for Check_Interfaces
11266 if Is_Interface (Parent_Type) then
11267 if Is_Task_Interface (Parent_Type) then
11270 elsif Is_Protected_Interface (Parent_Type) then
11271 Is_Protected := True;
11275 if Nkind (N) = N_Private_Extension_Declaration then
11277 -- Check that progenitors are compatible with declaration
11279 Iface := First (Interface_List (Def));
11280 while Present (Iface) loop
11281 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11283 Parent_Node := Parent (Base_Type (Iface_Typ));
11284 Iface_Def := Type_Definition (Parent_Node);
11286 if not Is_Interface (Iface_Typ) then
11287 Diagnose_Interface (Iface, Iface_Typ);
11289 Check_Ifaces (Iface_Def, Iface);
11295 if Is_Task and Is_Protected then
11297 ("type cannot derive from task and protected interface", N);
11303 -- Full type declaration of derived type.
11304 -- Check compatibility with parent if it is interface type
11306 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
11307 and then Is_Interface (Parent_Type)
11309 Parent_Node := Parent (Parent_Type);
11311 -- More detailed checks for interface varieties
11314 (Iface_Def => Type_Definition (Parent_Node),
11315 Error_Node => Subtype_Indication (Type_Definition (N)));
11318 Iface := First (Interface_List (Def));
11319 while Present (Iface) loop
11320 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
11322 Parent_Node := Parent (Base_Type (Iface_Typ));
11323 Iface_Def := Type_Definition (Parent_Node);
11325 if not Is_Interface (Iface_Typ) then
11326 Diagnose_Interface (Iface, Iface_Typ);
11329 -- "The declaration of a specific descendant of an interface
11330 -- type freezes the interface type" RM 13.14
11332 Freeze_Before (N, Iface_Typ);
11333 Check_Ifaces (Iface_Def, Error_Node => Iface);
11339 if Is_Task and Is_Protected then
11341 ("type cannot derive from task and protected interface", N);
11343 end Check_Interfaces;
11345 ------------------------------------
11346 -- Check_Or_Process_Discriminants --
11347 ------------------------------------
11349 -- If an incomplete or private type declaration was already given for the
11350 -- type, the discriminants may have already been processed if they were
11351 -- present on the incomplete declaration. In this case a full conformance
11352 -- check has been performed in Find_Type_Name, and we then recheck here
11353 -- some properties that can't be checked on the partial view alone.
11354 -- Otherwise we call Process_Discriminants.
11356 procedure Check_Or_Process_Discriminants
11359 Prev : Entity_Id := Empty)
11362 if Has_Discriminants (T) then
11364 -- Discriminants are already set on T if they were already present
11365 -- on the partial view. Make them visible to component declarations.
11369 -- Discriminant on T (full view) referencing expr on partial view
11371 Prev_D : Entity_Id;
11372 -- Entity of corresponding discriminant on partial view
11375 -- Discriminant specification for full view, expression is
11376 -- the syntactic copy on full view (which has been checked for
11377 -- conformance with partial view), only used here to post error
11381 D := First_Discriminant (T);
11382 New_D := First (Discriminant_Specifications (N));
11383 while Present (D) loop
11384 Prev_D := Current_Entity (D);
11385 Set_Current_Entity (D);
11386 Set_Is_Immediately_Visible (D);
11387 Set_Homonym (D, Prev_D);
11389 -- Handle the case where there is an untagged partial view and
11390 -- the full view is tagged: must disallow discriminants with
11391 -- defaults, unless compiling for Ada 2012, which allows a
11392 -- limited tagged type to have defaulted discriminants (see
11393 -- AI05-0214). However, suppress error here if it was already
11394 -- reported on the default expression of the partial view.
11396 if Is_Tagged_Type (T)
11397 and then Present (Expression (Parent (D)))
11398 and then (not Is_Limited_Type (Current_Scope)
11399 or else Ada_Version < Ada_2012)
11400 and then not Error_Posted (Expression (Parent (D)))
11402 if Ada_Version >= Ada_2012 then
11404 ("discriminants of nonlimited tagged type cannot have "
11406 Expression (New_D));
11409 ("discriminants of tagged type cannot have defaults",
11410 Expression (New_D));
11414 -- Ada 2005 (AI-230): Access discriminant allowed in
11415 -- non-limited record types.
11417 if Ada_Version < Ada_2005 then
11419 -- This restriction gets applied to the full type here. It
11420 -- has already been applied earlier to the partial view.
11422 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
11425 Next_Discriminant (D);
11430 elsif Present (Discriminant_Specifications (N)) then
11431 Process_Discriminants (N, Prev);
11433 end Check_Or_Process_Discriminants;
11435 ----------------------
11436 -- Check_Real_Bound --
11437 ----------------------
11439 procedure Check_Real_Bound (Bound : Node_Id) is
11441 if not Is_Real_Type (Etype (Bound)) then
11443 ("bound in real type definition must be of real type", Bound);
11445 elsif not Is_OK_Static_Expression (Bound) then
11446 Flag_Non_Static_Expr
11447 ("non-static expression used for real type bound!", Bound);
11454 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
11456 Resolve (Bound, Standard_Float);
11457 end Check_Real_Bound;
11459 ------------------------------
11460 -- Complete_Private_Subtype --
11461 ------------------------------
11463 procedure Complete_Private_Subtype
11466 Full_Base : Entity_Id;
11467 Related_Nod : Node_Id)
11469 Save_Next_Entity : Entity_Id;
11470 Save_Homonym : Entity_Id;
11473 -- Set semantic attributes for (implicit) private subtype completion.
11474 -- If the full type has no discriminants, then it is a copy of the
11475 -- full view of the base. Otherwise, it is a subtype of the base with
11476 -- a possible discriminant constraint. Save and restore the original
11477 -- Next_Entity field of full to ensure that the calls to Copy_Node do
11478 -- not corrupt the entity chain.
11480 -- Note that the type of the full view is the same entity as the type
11481 -- of the partial view. In this fashion, the subtype has access to the
11482 -- correct view of the parent.
11484 Save_Next_Entity := Next_Entity (Full);
11485 Save_Homonym := Homonym (Priv);
11487 case Ekind (Full_Base) is
11488 when E_Record_Type |
11494 Copy_Node (Priv, Full);
11496 Set_Has_Discriminants
11497 (Full, Has_Discriminants (Full_Base));
11498 Set_Has_Unknown_Discriminants
11499 (Full, Has_Unknown_Discriminants (Full_Base));
11500 Set_First_Entity (Full, First_Entity (Full_Base));
11501 Set_Last_Entity (Full, Last_Entity (Full_Base));
11503 -- If the underlying base type is constrained, we know that the
11504 -- full view of the subtype is constrained as well (the converse
11505 -- is not necessarily true).
11507 if Is_Constrained (Full_Base) then
11508 Set_Is_Constrained (Full);
11512 Copy_Node (Full_Base, Full);
11514 Set_Chars (Full, Chars (Priv));
11515 Conditional_Delay (Full, Priv);
11516 Set_Sloc (Full, Sloc (Priv));
11519 Set_Next_Entity (Full, Save_Next_Entity);
11520 Set_Homonym (Full, Save_Homonym);
11521 Set_Associated_Node_For_Itype (Full, Related_Nod);
11523 -- Set common attributes for all subtypes: kind, convention, etc.
11525 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
11526 Set_Convention (Full, Convention (Full_Base));
11528 -- The Etype of the full view is inconsistent. Gigi needs to see the
11529 -- structural full view, which is what the current scheme gives: the
11530 -- Etype of the full view is the etype of the full base. However, if the
11531 -- full base is a derived type, the full view then looks like a subtype
11532 -- of the parent, not a subtype of the full base. If instead we write:
11534 -- Set_Etype (Full, Full_Base);
11536 -- then we get inconsistencies in the front-end (confusion between
11537 -- views). Several outstanding bugs are related to this ???
11539 Set_Is_First_Subtype (Full, False);
11540 Set_Scope (Full, Scope (Priv));
11541 Set_Size_Info (Full, Full_Base);
11542 Set_RM_Size (Full, RM_Size (Full_Base));
11543 Set_Is_Itype (Full);
11545 -- A subtype of a private-type-without-discriminants, whose full-view
11546 -- has discriminants with default expressions, is not constrained.
11548 if not Has_Discriminants (Priv) then
11549 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
11551 if Has_Discriminants (Full_Base) then
11552 Set_Discriminant_Constraint
11553 (Full, Discriminant_Constraint (Full_Base));
11555 -- The partial view may have been indefinite, the full view
11558 Set_Has_Unknown_Discriminants
11559 (Full, Has_Unknown_Discriminants (Full_Base));
11563 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
11564 Set_Depends_On_Private (Full, Has_Private_Component (Full));
11566 -- Freeze the private subtype entity if its parent is delayed, and not
11567 -- already frozen. We skip this processing if the type is an anonymous
11568 -- subtype of a record component, or is the corresponding record of a
11569 -- protected type, since ???
11571 if not Is_Type (Scope (Full)) then
11572 Set_Has_Delayed_Freeze (Full,
11573 Has_Delayed_Freeze (Full_Base)
11574 and then (not Is_Frozen (Full_Base)));
11577 Set_Freeze_Node (Full, Empty);
11578 Set_Is_Frozen (Full, False);
11579 Set_Full_View (Priv, Full);
11581 if Has_Discriminants (Full) then
11582 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
11583 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
11585 if Has_Unknown_Discriminants (Full) then
11586 Set_Discriminant_Constraint (Full, No_Elist);
11590 if Ekind (Full_Base) = E_Record_Type
11591 and then Has_Discriminants (Full_Base)
11592 and then Has_Discriminants (Priv) -- might not, if errors
11593 and then not Has_Unknown_Discriminants (Priv)
11594 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
11596 Create_Constrained_Components
11597 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
11599 -- If the full base is itself derived from private, build a congruent
11600 -- subtype of its underlying type, for use by the back end. For a
11601 -- constrained record component, the declaration cannot be placed on
11602 -- the component list, but it must nevertheless be built an analyzed, to
11603 -- supply enough information for Gigi to compute the size of component.
11605 elsif Ekind (Full_Base) in Private_Kind
11606 and then Is_Derived_Type (Full_Base)
11607 and then Has_Discriminants (Full_Base)
11608 and then (Ekind (Current_Scope) /= E_Record_Subtype)
11610 if not Is_Itype (Priv)
11612 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
11614 Build_Underlying_Full_View
11615 (Parent (Priv), Full, Etype (Full_Base));
11617 elsif Nkind (Related_Nod) = N_Component_Declaration then
11618 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
11621 elsif Is_Record_Type (Full_Base) then
11623 -- Show Full is simply a renaming of Full_Base
11625 Set_Cloned_Subtype (Full, Full_Base);
11628 -- It is unsafe to share the bounds of a scalar type, because the Itype
11629 -- is elaborated on demand, and if a bound is non-static then different
11630 -- orders of elaboration in different units will lead to different
11631 -- external symbols.
11633 if Is_Scalar_Type (Full_Base) then
11634 Set_Scalar_Range (Full,
11635 Make_Range (Sloc (Related_Nod),
11637 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
11639 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
11641 -- This completion inherits the bounds of the full parent, but if
11642 -- the parent is an unconstrained floating point type, so is the
11645 if Is_Floating_Point_Type (Full_Base) then
11646 Set_Includes_Infinities
11647 (Scalar_Range (Full), Has_Infinities (Full_Base));
11651 -- ??? It seems that a lot of fields are missing that should be copied
11652 -- from Full_Base to Full. Here are some that are introduced in a
11653 -- non-disruptive way but a cleanup is necessary.
11655 if Is_Tagged_Type (Full_Base) then
11656 Set_Is_Tagged_Type (Full);
11657 Set_Direct_Primitive_Operations
11658 (Full, Direct_Primitive_Operations (Full_Base));
11659 Set_No_Tagged_Streams_Pragma
11660 (Full, No_Tagged_Streams_Pragma (Full_Base));
11662 -- Inherit class_wide type of full_base in case the partial view was
11663 -- not tagged. Otherwise it has already been created when the private
11664 -- subtype was analyzed.
11666 if No (Class_Wide_Type (Full)) then
11667 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
11670 -- If this is a subtype of a protected or task type, constrain its
11671 -- corresponding record, unless this is a subtype without constraints,
11672 -- i.e. a simple renaming as with an actual subtype in an instance.
11674 elsif Is_Concurrent_Type (Full_Base) then
11675 if Has_Discriminants (Full)
11676 and then Present (Corresponding_Record_Type (Full_Base))
11678 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
11680 Set_Corresponding_Record_Type (Full,
11681 Constrain_Corresponding_Record
11682 (Full, Corresponding_Record_Type (Full_Base), Related_Nod));
11685 Set_Corresponding_Record_Type (Full,
11686 Corresponding_Record_Type (Full_Base));
11690 -- Link rep item chain, and also setting of Has_Predicates from private
11691 -- subtype to full subtype, since we will need these on the full subtype
11692 -- to create the predicate function. Note that the full subtype may
11693 -- already have rep items, inherited from the full view of the base
11694 -- type, so we must be sure not to overwrite these entries.
11699 Next_Item : Node_Id;
11702 Item := First_Rep_Item (Full);
11704 -- If no existing rep items on full type, we can just link directly
11705 -- to the list of items on the private type, if any exist.. Same if
11706 -- the rep items are only those inherited from the base
11709 or else Nkind (Item) /= N_Aspect_Specification
11710 or else Entity (Item) = Full_Base)
11711 and then Present (First_Rep_Item (Priv))
11713 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
11715 -- Otherwise, search to the end of items currently linked to the full
11716 -- subtype and append the private items to the end. However, if Priv
11717 -- and Full already have the same list of rep items, then the append
11718 -- is not done, as that would create a circularity.
11720 elsif Item /= First_Rep_Item (Priv) then
11723 Next_Item := Next_Rep_Item (Item);
11724 exit when No (Next_Item);
11727 -- If the private view has aspect specifications, the full view
11728 -- inherits them. Since these aspects may already have been
11729 -- attached to the full view during derivation, do not append
11730 -- them if already present.
11732 if Item = First_Rep_Item (Priv) then
11738 -- And link the private type items at the end of the chain
11741 Set_Next_Rep_Item (Item, First_Rep_Item (Priv));
11746 -- Make sure Has_Predicates is set on full type if it is set on the
11747 -- private type. Note that it may already be set on the full type and
11748 -- if so, we don't want to unset it.
11750 if Has_Predicates (Priv) then
11751 Set_Has_Predicates (Full);
11753 end Complete_Private_Subtype;
11755 ----------------------------
11756 -- Constant_Redeclaration --
11757 ----------------------------
11759 procedure Constant_Redeclaration
11764 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
11765 Obj_Def : constant Node_Id := Object_Definition (N);
11768 procedure Check_Possible_Deferred_Completion
11769 (Prev_Id : Entity_Id;
11770 Prev_Obj_Def : Node_Id;
11771 Curr_Obj_Def : Node_Id);
11772 -- Determine whether the two object definitions describe the partial
11773 -- and the full view of a constrained deferred constant. Generate
11774 -- a subtype for the full view and verify that it statically matches
11775 -- the subtype of the partial view.
11777 procedure Check_Recursive_Declaration (Typ : Entity_Id);
11778 -- If deferred constant is an access type initialized with an allocator,
11779 -- check whether there is an illegal recursion in the definition,
11780 -- through a default value of some record subcomponent. This is normally
11781 -- detected when generating init procs, but requires this additional
11782 -- mechanism when expansion is disabled.
11784 ----------------------------------------
11785 -- Check_Possible_Deferred_Completion --
11786 ----------------------------------------
11788 procedure Check_Possible_Deferred_Completion
11789 (Prev_Id : Entity_Id;
11790 Prev_Obj_Def : Node_Id;
11791 Curr_Obj_Def : Node_Id)
11794 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
11795 and then Present (Constraint (Prev_Obj_Def))
11796 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
11797 and then Present (Constraint (Curr_Obj_Def))
11800 Loc : constant Source_Ptr := Sloc (N);
11801 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'S');
11802 Decl : constant Node_Id :=
11803 Make_Subtype_Declaration (Loc,
11804 Defining_Identifier => Def_Id,
11805 Subtype_Indication =>
11806 Relocate_Node (Curr_Obj_Def));
11809 Insert_Before_And_Analyze (N, Decl);
11810 Set_Etype (Id, Def_Id);
11812 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
11813 Error_Msg_Sloc := Sloc (Prev_Id);
11814 Error_Msg_N ("subtype does not statically match deferred "
11815 & "declaration #", N);
11819 end Check_Possible_Deferred_Completion;
11821 ---------------------------------
11822 -- Check_Recursive_Declaration --
11823 ---------------------------------
11825 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
11829 if Is_Record_Type (Typ) then
11830 Comp := First_Component (Typ);
11831 while Present (Comp) loop
11832 if Comes_From_Source (Comp) then
11833 if Present (Expression (Parent (Comp)))
11834 and then Is_Entity_Name (Expression (Parent (Comp)))
11835 and then Entity (Expression (Parent (Comp))) = Prev
11837 Error_Msg_Sloc := Sloc (Parent (Comp));
11839 ("illegal circularity with declaration for & #",
11843 elsif Is_Record_Type (Etype (Comp)) then
11844 Check_Recursive_Declaration (Etype (Comp));
11848 Next_Component (Comp);
11851 end Check_Recursive_Declaration;
11853 -- Start of processing for Constant_Redeclaration
11856 if Nkind (Parent (Prev)) = N_Object_Declaration then
11857 if Nkind (Object_Definition
11858 (Parent (Prev))) = N_Subtype_Indication
11860 -- Find type of new declaration. The constraints of the two
11861 -- views must match statically, but there is no point in
11862 -- creating an itype for the full view.
11864 if Nkind (Obj_Def) = N_Subtype_Indication then
11865 Find_Type (Subtype_Mark (Obj_Def));
11866 New_T := Entity (Subtype_Mark (Obj_Def));
11869 Find_Type (Obj_Def);
11870 New_T := Entity (Obj_Def);
11876 -- The full view may impose a constraint, even if the partial
11877 -- view does not, so construct the subtype.
11879 New_T := Find_Type_Of_Object (Obj_Def, N);
11884 -- Current declaration is illegal, diagnosed below in Enter_Name
11890 -- If previous full declaration or a renaming declaration exists, or if
11891 -- a homograph is present, let Enter_Name handle it, either with an
11892 -- error or with the removal of an overridden implicit subprogram.
11893 -- The previous one is a full declaration if it has an expression
11894 -- (which in the case of an aggregate is indicated by the Init flag).
11896 if Ekind (Prev) /= E_Constant
11897 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
11898 or else Present (Expression (Parent (Prev)))
11899 or else Has_Init_Expression (Parent (Prev))
11900 or else Present (Full_View (Prev))
11904 -- Verify that types of both declarations match, or else that both types
11905 -- are anonymous access types whose designated subtypes statically match
11906 -- (as allowed in Ada 2005 by AI-385).
11908 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
11910 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
11911 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
11912 or else Is_Access_Constant (Etype (New_T)) /=
11913 Is_Access_Constant (Etype (Prev))
11914 or else Can_Never_Be_Null (Etype (New_T)) /=
11915 Can_Never_Be_Null (Etype (Prev))
11916 or else Null_Exclusion_Present (Parent (Prev)) /=
11917 Null_Exclusion_Present (Parent (Id))
11918 or else not Subtypes_Statically_Match
11919 (Designated_Type (Etype (Prev)),
11920 Designated_Type (Etype (New_T))))
11922 Error_Msg_Sloc := Sloc (Prev);
11923 Error_Msg_N ("type does not match declaration#", N);
11924 Set_Full_View (Prev, Id);
11925 Set_Etype (Id, Any_Type);
11927 -- A deferred constant whose type is an anonymous array is always
11928 -- illegal (unless imported). A detailed error message might be
11929 -- helpful for Ada beginners.
11931 if Nkind (Object_Definition (Parent (Prev)))
11932 = N_Constrained_Array_Definition
11933 and then Nkind (Object_Definition (N))
11934 = N_Constrained_Array_Definition
11936 Error_Msg_N ("\each anonymous array is a distinct type", N);
11937 Error_Msg_N ("a deferred constant must have a named type",
11938 Object_Definition (Parent (Prev)));
11942 Null_Exclusion_Present (Parent (Prev))
11943 and then not Null_Exclusion_Present (N)
11945 Error_Msg_Sloc := Sloc (Prev);
11946 Error_Msg_N ("null-exclusion does not match declaration#", N);
11947 Set_Full_View (Prev, Id);
11948 Set_Etype (Id, Any_Type);
11950 -- If so, process the full constant declaration
11953 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
11954 -- the deferred declaration is constrained, then the subtype defined
11955 -- by the subtype_indication in the full declaration shall match it
11958 Check_Possible_Deferred_Completion
11960 Prev_Obj_Def => Object_Definition (Parent (Prev)),
11961 Curr_Obj_Def => Obj_Def);
11963 Set_Full_View (Prev, Id);
11964 Set_Is_Public (Id, Is_Public (Prev));
11965 Set_Is_Internal (Id);
11966 Append_Entity (Id, Current_Scope);
11968 -- Check ALIASED present if present before (RM 7.4(7))
11970 if Is_Aliased (Prev)
11971 and then not Aliased_Present (N)
11973 Error_Msg_Sloc := Sloc (Prev);
11974 Error_Msg_N ("ALIASED required (see declaration #)", N);
11977 -- Check that placement is in private part and that the incomplete
11978 -- declaration appeared in the visible part.
11980 if Ekind (Current_Scope) = E_Package
11981 and then not In_Private_Part (Current_Scope)
11983 Error_Msg_Sloc := Sloc (Prev);
11985 ("full constant for declaration # must be in private part", N);
11987 elsif Ekind (Current_Scope) = E_Package
11989 List_Containing (Parent (Prev)) /=
11990 Visible_Declarations (Package_Specification (Current_Scope))
11993 ("deferred constant must be declared in visible part",
11997 if Is_Access_Type (T)
11998 and then Nkind (Expression (N)) = N_Allocator
12000 Check_Recursive_Declaration (Designated_Type (T));
12003 -- A deferred constant is a visible entity. If type has invariants,
12004 -- verify that the initial value satisfies them.
12006 if Has_Invariants (T) and then Present (Invariant_Procedure (T)) then
12008 Make_Invariant_Call (New_Occurrence_Of (Prev, Sloc (N))));
12011 end Constant_Redeclaration;
12013 ----------------------
12014 -- Constrain_Access --
12015 ----------------------
12017 procedure Constrain_Access
12018 (Def_Id : in out Entity_Id;
12020 Related_Nod : Node_Id)
12022 T : constant Entity_Id := Entity (Subtype_Mark (S));
12023 Desig_Type : constant Entity_Id := Designated_Type (T);
12024 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
12025 Constraint_OK : Boolean := True;
12028 if Is_Array_Type (Desig_Type) then
12029 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
12031 elsif (Is_Record_Type (Desig_Type)
12032 or else Is_Incomplete_Or_Private_Type (Desig_Type))
12033 and then not Is_Constrained (Desig_Type)
12035 -- ??? The following code is a temporary bypass to ignore a
12036 -- discriminant constraint on access type if it is constraining
12037 -- the current record. Avoid creating the implicit subtype of the
12038 -- record we are currently compiling since right now, we cannot
12039 -- handle these. For now, just return the access type itself.
12041 if Desig_Type = Current_Scope
12042 and then No (Def_Id)
12044 Set_Ekind (Desig_Subtype, E_Record_Subtype);
12045 Def_Id := Entity (Subtype_Mark (S));
12047 -- This call added to ensure that the constraint is analyzed
12048 -- (needed for a B test). Note that we still return early from
12049 -- this procedure to avoid recursive processing. ???
12051 Constrain_Discriminated_Type
12052 (Desig_Subtype, S, Related_Nod, For_Access => True);
12056 -- Enforce rule that the constraint is illegal if there is an
12057 -- unconstrained view of the designated type. This means that the
12058 -- partial view (either a private type declaration or a derivation
12059 -- from a private type) has no discriminants. (Defect Report
12060 -- 8652/0008, Technical Corrigendum 1, checked by ACATS B371001).
12062 -- Rule updated for Ada 2005: The private type is said to have
12063 -- a constrained partial view, given that objects of the type
12064 -- can be declared. Furthermore, the rule applies to all access
12065 -- types, unlike the rule concerning default discriminants (see
12068 if (Ekind (T) = E_General_Access_Type or else Ada_Version >= Ada_2005)
12069 and then Has_Private_Declaration (Desig_Type)
12070 and then In_Open_Scopes (Scope (Desig_Type))
12071 and then Has_Discriminants (Desig_Type)
12074 Pack : constant Node_Id :=
12075 Unit_Declaration_Node (Scope (Desig_Type));
12080 if Nkind (Pack) = N_Package_Declaration then
12081 Decls := Visible_Declarations (Specification (Pack));
12082 Decl := First (Decls);
12083 while Present (Decl) loop
12084 if (Nkind (Decl) = N_Private_Type_Declaration
12085 and then Chars (Defining_Identifier (Decl)) =
12086 Chars (Desig_Type))
12089 (Nkind (Decl) = N_Full_Type_Declaration
12091 Chars (Defining_Identifier (Decl)) =
12093 and then Is_Derived_Type (Desig_Type)
12095 Has_Private_Declaration (Etype (Desig_Type)))
12097 if No (Discriminant_Specifications (Decl)) then
12099 ("cannot constrain access type if designated "
12100 & "type has constrained partial view", S);
12112 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
12113 For_Access => True);
12115 elsif Is_Concurrent_Type (Desig_Type)
12116 and then not Is_Constrained (Desig_Type)
12118 Constrain_Concurrent (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
12121 Error_Msg_N ("invalid constraint on access type", S);
12123 -- We simply ignore an invalid constraint
12125 Desig_Subtype := Desig_Type;
12126 Constraint_OK := False;
12129 if No (Def_Id) then
12130 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
12132 Set_Ekind (Def_Id, E_Access_Subtype);
12135 if Constraint_OK then
12136 Set_Etype (Def_Id, Base_Type (T));
12138 if Is_Private_Type (Desig_Type) then
12139 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
12142 Set_Etype (Def_Id, Any_Type);
12145 Set_Size_Info (Def_Id, T);
12146 Set_Is_Constrained (Def_Id, Constraint_OK);
12147 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
12148 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12149 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
12151 Conditional_Delay (Def_Id, T);
12153 -- AI-363 : Subtypes of general access types whose designated types have
12154 -- default discriminants are disallowed. In instances, the rule has to
12155 -- be checked against the actual, of which T is the subtype. In a
12156 -- generic body, the rule is checked assuming that the actual type has
12157 -- defaulted discriminants.
12159 if Ada_Version >= Ada_2005 or else Warn_On_Ada_2005_Compatibility then
12160 if Ekind (Base_Type (T)) = E_General_Access_Type
12161 and then Has_Defaulted_Discriminants (Desig_Type)
12163 if Ada_Version < Ada_2005 then
12165 ("access subtype of general access type would not " &
12166 "be allowed in Ada 2005?y?", S);
12169 ("access subtype of general access type not allowed", S);
12172 Error_Msg_N ("\discriminants have defaults", S);
12174 elsif Is_Access_Type (T)
12175 and then Is_Generic_Type (Desig_Type)
12176 and then Has_Discriminants (Desig_Type)
12177 and then In_Package_Body (Current_Scope)
12179 if Ada_Version < Ada_2005 then
12181 ("access subtype would not be allowed in generic body "
12182 & "in Ada 2005?y?", S);
12185 ("access subtype not allowed in generic body", S);
12189 ("\designated type is a discriminated formal", S);
12192 end Constrain_Access;
12194 ---------------------
12195 -- Constrain_Array --
12196 ---------------------
12198 procedure Constrain_Array
12199 (Def_Id : in out Entity_Id;
12201 Related_Nod : Node_Id;
12202 Related_Id : Entity_Id;
12203 Suffix : Character)
12205 C : constant Node_Id := Constraint (SI);
12206 Number_Of_Constraints : Nat := 0;
12209 Constraint_OK : Boolean := True;
12212 T := Entity (Subtype_Mark (SI));
12214 if Is_Access_Type (T) then
12215 T := Designated_Type (T);
12218 -- If an index constraint follows a subtype mark in a subtype indication
12219 -- then the type or subtype denoted by the subtype mark must not already
12220 -- impose an index constraint. The subtype mark must denote either an
12221 -- unconstrained array type or an access type whose designated type
12222 -- is such an array type... (RM 3.6.1)
12224 if Is_Constrained (T) then
12225 Error_Msg_N ("array type is already constrained", Subtype_Mark (SI));
12226 Constraint_OK := False;
12229 S := First (Constraints (C));
12230 while Present (S) loop
12231 Number_Of_Constraints := Number_Of_Constraints + 1;
12235 -- In either case, the index constraint must provide a discrete
12236 -- range for each index of the array type and the type of each
12237 -- discrete range must be the same as that of the corresponding
12238 -- index. (RM 3.6.1)
12240 if Number_Of_Constraints /= Number_Dimensions (T) then
12241 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
12242 Constraint_OK := False;
12245 S := First (Constraints (C));
12246 Index := First_Index (T);
12249 -- Apply constraints to each index type
12251 for J in 1 .. Number_Of_Constraints loop
12252 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
12260 if No (Def_Id) then
12262 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
12263 Set_Parent (Def_Id, Related_Nod);
12266 Set_Ekind (Def_Id, E_Array_Subtype);
12269 Set_Size_Info (Def_Id, (T));
12270 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12271 Set_Etype (Def_Id, Base_Type (T));
12273 if Constraint_OK then
12274 Set_First_Index (Def_Id, First (Constraints (C)));
12276 Set_First_Index (Def_Id, First_Index (T));
12279 Set_Is_Constrained (Def_Id, True);
12280 Set_Is_Aliased (Def_Id, Is_Aliased (T));
12281 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12283 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
12284 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
12286 -- A subtype does not inherit the Packed_Array_Impl_Type of is parent.
12287 -- We need to initialize the attribute because if Def_Id is previously
12288 -- analyzed through a limited_with clause, it will have the attributes
12289 -- of an incomplete type, one of which is an Elist that overlaps the
12290 -- Packed_Array_Impl_Type field.
12292 Set_Packed_Array_Impl_Type (Def_Id, Empty);
12294 -- Build a freeze node if parent still needs one. Also make sure that
12295 -- the Depends_On_Private status is set because the subtype will need
12296 -- reprocessing at the time the base type does, and also we must set a
12297 -- conditional delay.
12299 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
12300 Conditional_Delay (Def_Id, T);
12301 end Constrain_Array;
12303 ------------------------------
12304 -- Constrain_Component_Type --
12305 ------------------------------
12307 function Constrain_Component_Type
12309 Constrained_Typ : Entity_Id;
12310 Related_Node : Node_Id;
12312 Constraints : Elist_Id) return Entity_Id
12314 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
12315 Compon_Type : constant Entity_Id := Etype (Comp);
12317 function Build_Constrained_Array_Type
12318 (Old_Type : Entity_Id) return Entity_Id;
12319 -- If Old_Type is an array type, one of whose indexes is constrained
12320 -- by a discriminant, build an Itype whose constraint replaces the
12321 -- discriminant with its value in the constraint.
12323 function Build_Constrained_Discriminated_Type
12324 (Old_Type : Entity_Id) return Entity_Id;
12325 -- Ditto for record components
12327 function Build_Constrained_Access_Type
12328 (Old_Type : Entity_Id) return Entity_Id;
12329 -- Ditto for access types. Makes use of previous two functions, to
12330 -- constrain designated type.
12332 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
12333 -- T is an array or discriminated type, C is a list of constraints
12334 -- that apply to T. This routine builds the constrained subtype.
12336 function Is_Discriminant (Expr : Node_Id) return Boolean;
12337 -- Returns True if Expr is a discriminant
12339 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
12340 -- Find the value of discriminant Discrim in Constraint
12342 -----------------------------------
12343 -- Build_Constrained_Access_Type --
12344 -----------------------------------
12346 function Build_Constrained_Access_Type
12347 (Old_Type : Entity_Id) return Entity_Id
12349 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
12351 Desig_Subtype : Entity_Id;
12355 -- if the original access type was not embedded in the enclosing
12356 -- type definition, there is no need to produce a new access
12357 -- subtype. In fact every access type with an explicit constraint
12358 -- generates an itype whose scope is the enclosing record.
12360 if not Is_Type (Scope (Old_Type)) then
12363 elsif Is_Array_Type (Desig_Type) then
12364 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
12366 elsif Has_Discriminants (Desig_Type) then
12368 -- This may be an access type to an enclosing record type for
12369 -- which we are constructing the constrained components. Return
12370 -- the enclosing record subtype. This is not always correct,
12371 -- but avoids infinite recursion. ???
12373 Desig_Subtype := Any_Type;
12375 for J in reverse 0 .. Scope_Stack.Last loop
12376 Scop := Scope_Stack.Table (J).Entity;
12379 and then Base_Type (Scop) = Base_Type (Desig_Type)
12381 Desig_Subtype := Scop;
12384 exit when not Is_Type (Scop);
12387 if Desig_Subtype = Any_Type then
12389 Build_Constrained_Discriminated_Type (Desig_Type);
12396 if Desig_Subtype /= Desig_Type then
12398 -- The Related_Node better be here or else we won't be able
12399 -- to attach new itypes to a node in the tree.
12401 pragma Assert (Present (Related_Node));
12403 Itype := Create_Itype (E_Access_Subtype, Related_Node);
12405 Set_Etype (Itype, Base_Type (Old_Type));
12406 Set_Size_Info (Itype, (Old_Type));
12407 Set_Directly_Designated_Type (Itype, Desig_Subtype);
12408 Set_Depends_On_Private (Itype, Has_Private_Component
12410 Set_Is_Access_Constant (Itype, Is_Access_Constant
12413 -- The new itype needs freezing when it depends on a not frozen
12414 -- type and the enclosing subtype needs freezing.
12416 if Has_Delayed_Freeze (Constrained_Typ)
12417 and then not Is_Frozen (Constrained_Typ)
12419 Conditional_Delay (Itype, Base_Type (Old_Type));
12427 end Build_Constrained_Access_Type;
12429 ----------------------------------
12430 -- Build_Constrained_Array_Type --
12431 ----------------------------------
12433 function Build_Constrained_Array_Type
12434 (Old_Type : Entity_Id) return Entity_Id
12438 Old_Index : Node_Id;
12439 Range_Node : Node_Id;
12440 Constr_List : List_Id;
12442 Need_To_Create_Itype : Boolean := False;
12445 Old_Index := First_Index (Old_Type);
12446 while Present (Old_Index) loop
12447 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12449 if Is_Discriminant (Lo_Expr)
12451 Is_Discriminant (Hi_Expr)
12453 Need_To_Create_Itype := True;
12456 Next_Index (Old_Index);
12459 if Need_To_Create_Itype then
12460 Constr_List := New_List;
12462 Old_Index := First_Index (Old_Type);
12463 while Present (Old_Index) loop
12464 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
12466 if Is_Discriminant (Lo_Expr) then
12467 Lo_Expr := Get_Discr_Value (Lo_Expr);
12470 if Is_Discriminant (Hi_Expr) then
12471 Hi_Expr := Get_Discr_Value (Hi_Expr);
12476 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
12478 Append (Range_Node, To => Constr_List);
12480 Next_Index (Old_Index);
12483 return Build_Subtype (Old_Type, Constr_List);
12488 end Build_Constrained_Array_Type;
12490 ------------------------------------------
12491 -- Build_Constrained_Discriminated_Type --
12492 ------------------------------------------
12494 function Build_Constrained_Discriminated_Type
12495 (Old_Type : Entity_Id) return Entity_Id
12498 Constr_List : List_Id;
12499 Old_Constraint : Elmt_Id;
12501 Need_To_Create_Itype : Boolean := False;
12504 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12505 while Present (Old_Constraint) loop
12506 Expr := Node (Old_Constraint);
12508 if Is_Discriminant (Expr) then
12509 Need_To_Create_Itype := True;
12512 Next_Elmt (Old_Constraint);
12515 if Need_To_Create_Itype then
12516 Constr_List := New_List;
12518 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
12519 while Present (Old_Constraint) loop
12520 Expr := Node (Old_Constraint);
12522 if Is_Discriminant (Expr) then
12523 Expr := Get_Discr_Value (Expr);
12526 Append (New_Copy_Tree (Expr), To => Constr_List);
12528 Next_Elmt (Old_Constraint);
12531 return Build_Subtype (Old_Type, Constr_List);
12536 end Build_Constrained_Discriminated_Type;
12538 -------------------
12539 -- Build_Subtype --
12540 -------------------
12542 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
12544 Subtyp_Decl : Node_Id;
12545 Def_Id : Entity_Id;
12546 Btyp : Entity_Id := Base_Type (T);
12549 -- The Related_Node better be here or else we won't be able to
12550 -- attach new itypes to a node in the tree.
12552 pragma Assert (Present (Related_Node));
12554 -- If the view of the component's type is incomplete or private
12555 -- with unknown discriminants, then the constraint must be applied
12556 -- to the full type.
12558 if Has_Unknown_Discriminants (Btyp)
12559 and then Present (Underlying_Type (Btyp))
12561 Btyp := Underlying_Type (Btyp);
12565 Make_Subtype_Indication (Loc,
12566 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
12567 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
12569 Def_Id := Create_Itype (Ekind (T), Related_Node);
12572 Make_Subtype_Declaration (Loc,
12573 Defining_Identifier => Def_Id,
12574 Subtype_Indication => Indic);
12576 Set_Parent (Subtyp_Decl, Parent (Related_Node));
12578 -- Itypes must be analyzed with checks off (see package Itypes)
12580 Analyze (Subtyp_Decl, Suppress => All_Checks);
12585 ---------------------
12586 -- Get_Discr_Value --
12587 ---------------------
12589 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
12594 -- The discriminant may be declared for the type, in which case we
12595 -- find it by iterating over the list of discriminants. If the
12596 -- discriminant is inherited from a parent type, it appears as the
12597 -- corresponding discriminant of the current type. This will be the
12598 -- case when constraining an inherited component whose constraint is
12599 -- given by a discriminant of the parent.
12601 D := First_Discriminant (Typ);
12602 E := First_Elmt (Constraints);
12604 while Present (D) loop
12605 if D = Entity (Discrim)
12606 or else D = CR_Discriminant (Entity (Discrim))
12607 or else Corresponding_Discriminant (D) = Entity (Discrim)
12612 Next_Discriminant (D);
12616 -- The Corresponding_Discriminant mechanism is incomplete, because
12617 -- the correspondence between new and old discriminants is not one
12618 -- to one: one new discriminant can constrain several old ones. In
12619 -- that case, scan sequentially the stored_constraint, the list of
12620 -- discriminants of the parents, and the constraints.
12622 -- Previous code checked for the present of the Stored_Constraint
12623 -- list for the derived type, but did not use it at all. Should it
12624 -- be present when the component is a discriminated task type?
12626 if Is_Derived_Type (Typ)
12627 and then Scope (Entity (Discrim)) = Etype (Typ)
12629 D := First_Discriminant (Etype (Typ));
12630 E := First_Elmt (Constraints);
12631 while Present (D) loop
12632 if D = Entity (Discrim) then
12636 Next_Discriminant (D);
12641 -- Something is wrong if we did not find the value
12643 raise Program_Error;
12644 end Get_Discr_Value;
12646 ---------------------
12647 -- Is_Discriminant --
12648 ---------------------
12650 function Is_Discriminant (Expr : Node_Id) return Boolean is
12651 Discrim_Scope : Entity_Id;
12654 if Denotes_Discriminant (Expr) then
12655 Discrim_Scope := Scope (Entity (Expr));
12657 -- Either we have a reference to one of Typ's discriminants,
12659 pragma Assert (Discrim_Scope = Typ
12661 -- or to the discriminants of the parent type, in the case
12662 -- of a derivation of a tagged type with variants.
12664 or else Discrim_Scope = Etype (Typ)
12665 or else Full_View (Discrim_Scope) = Etype (Typ)
12667 -- or same as above for the case where the discriminants
12668 -- were declared in Typ's private view.
12670 or else (Is_Private_Type (Discrim_Scope)
12671 and then Chars (Discrim_Scope) = Chars (Typ))
12673 -- or else we are deriving from the full view and the
12674 -- discriminant is declared in the private entity.
12676 or else (Is_Private_Type (Typ)
12677 and then Chars (Discrim_Scope) = Chars (Typ))
12679 -- Or we are constrained the corresponding record of a
12680 -- synchronized type that completes a private declaration.
12682 or else (Is_Concurrent_Record_Type (Typ)
12684 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
12686 -- or we have a class-wide type, in which case make sure the
12687 -- discriminant found belongs to the root type.
12689 or else (Is_Class_Wide_Type (Typ)
12690 and then Etype (Typ) = Discrim_Scope));
12695 -- In all other cases we have something wrong
12698 end Is_Discriminant;
12700 -- Start of processing for Constrain_Component_Type
12703 if Nkind (Parent (Comp)) = N_Component_Declaration
12704 and then Comes_From_Source (Parent (Comp))
12705 and then Comes_From_Source
12706 (Subtype_Indication (Component_Definition (Parent (Comp))))
12709 (Subtype_Indication (Component_Definition (Parent (Comp))))
12711 return Compon_Type;
12713 elsif Is_Array_Type (Compon_Type) then
12714 return Build_Constrained_Array_Type (Compon_Type);
12716 elsif Has_Discriminants (Compon_Type) then
12717 return Build_Constrained_Discriminated_Type (Compon_Type);
12719 elsif Is_Access_Type (Compon_Type) then
12720 return Build_Constrained_Access_Type (Compon_Type);
12723 return Compon_Type;
12725 end Constrain_Component_Type;
12727 --------------------------
12728 -- Constrain_Concurrent --
12729 --------------------------
12731 -- For concurrent types, the associated record value type carries the same
12732 -- discriminants, so when we constrain a concurrent type, we must constrain
12733 -- the corresponding record type as well.
12735 procedure Constrain_Concurrent
12736 (Def_Id : in out Entity_Id;
12738 Related_Nod : Node_Id;
12739 Related_Id : Entity_Id;
12740 Suffix : Character)
12742 -- Retrieve Base_Type to ensure getting to the concurrent type in the
12743 -- case of a private subtype (needed when only doing semantic analysis).
12745 T_Ent : Entity_Id := Base_Type (Entity (Subtype_Mark (SI)));
12749 if Is_Access_Type (T_Ent) then
12750 T_Ent := Designated_Type (T_Ent);
12753 T_Val := Corresponding_Record_Type (T_Ent);
12755 if Present (T_Val) then
12757 if No (Def_Id) then
12758 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12761 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12763 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
12764 Set_Corresponding_Record_Type (Def_Id,
12765 Constrain_Corresponding_Record (Def_Id, T_Val, Related_Nod));
12768 -- If there is no associated record, expansion is disabled and this
12769 -- is a generic context. Create a subtype in any case, so that
12770 -- semantic analysis can proceed.
12772 if No (Def_Id) then
12773 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
12776 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
12778 end Constrain_Concurrent;
12780 ------------------------------------
12781 -- Constrain_Corresponding_Record --
12782 ------------------------------------
12784 function Constrain_Corresponding_Record
12785 (Prot_Subt : Entity_Id;
12786 Corr_Rec : Entity_Id;
12787 Related_Nod : Node_Id) return Entity_Id
12789 T_Sub : constant Entity_Id :=
12790 Create_Itype (E_Record_Subtype, Related_Nod, Corr_Rec, 'C');
12793 Set_Etype (T_Sub, Corr_Rec);
12794 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
12795 Set_Is_Constrained (T_Sub, True);
12796 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
12797 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
12799 if Has_Discriminants (Prot_Subt) then -- False only if errors.
12800 Set_Discriminant_Constraint
12801 (T_Sub, Discriminant_Constraint (Prot_Subt));
12802 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
12803 Create_Constrained_Components
12804 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
12807 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
12809 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
12810 Conditional_Delay (T_Sub, Corr_Rec);
12813 -- This is a component subtype: it will be frozen in the context of
12814 -- the enclosing record's init_proc, so that discriminant references
12815 -- are resolved to discriminals. (Note: we used to skip freezing
12816 -- altogether in that case, which caused errors downstream for
12817 -- components of a bit packed array type).
12819 Set_Has_Delayed_Freeze (T_Sub);
12823 end Constrain_Corresponding_Record;
12825 -----------------------
12826 -- Constrain_Decimal --
12827 -----------------------
12829 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
12830 T : constant Entity_Id := Entity (Subtype_Mark (S));
12831 C : constant Node_Id := Constraint (S);
12832 Loc : constant Source_Ptr := Sloc (C);
12833 Range_Expr : Node_Id;
12834 Digits_Expr : Node_Id;
12839 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
12841 if Nkind (C) = N_Range_Constraint then
12842 Range_Expr := Range_Expression (C);
12843 Digits_Val := Digits_Value (T);
12846 pragma Assert (Nkind (C) = N_Digits_Constraint);
12848 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
12850 Digits_Expr := Digits_Expression (C);
12851 Analyze_And_Resolve (Digits_Expr, Any_Integer);
12853 Check_Digits_Expression (Digits_Expr);
12854 Digits_Val := Expr_Value (Digits_Expr);
12856 if Digits_Val > Digits_Value (T) then
12858 ("digits expression is incompatible with subtype", C);
12859 Digits_Val := Digits_Value (T);
12862 if Present (Range_Constraint (C)) then
12863 Range_Expr := Range_Expression (Range_Constraint (C));
12865 Range_Expr := Empty;
12869 Set_Etype (Def_Id, Base_Type (T));
12870 Set_Size_Info (Def_Id, (T));
12871 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
12872 Set_Delta_Value (Def_Id, Delta_Value (T));
12873 Set_Scale_Value (Def_Id, Scale_Value (T));
12874 Set_Small_Value (Def_Id, Small_Value (T));
12875 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
12876 Set_Digits_Value (Def_Id, Digits_Val);
12878 -- Manufacture range from given digits value if no range present
12880 if No (Range_Expr) then
12881 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
12885 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
12887 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
12890 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
12891 Set_Discrete_RM_Size (Def_Id);
12893 -- Unconditionally delay the freeze, since we cannot set size
12894 -- information in all cases correctly until the freeze point.
12896 Set_Has_Delayed_Freeze (Def_Id);
12897 end Constrain_Decimal;
12899 ----------------------------------
12900 -- Constrain_Discriminated_Type --
12901 ----------------------------------
12903 procedure Constrain_Discriminated_Type
12904 (Def_Id : Entity_Id;
12906 Related_Nod : Node_Id;
12907 For_Access : Boolean := False)
12909 E : constant Entity_Id := Entity (Subtype_Mark (S));
12912 Elist : Elist_Id := New_Elmt_List;
12914 procedure Fixup_Bad_Constraint;
12915 -- This is called after finding a bad constraint, and after having
12916 -- posted an appropriate error message. The mission is to leave the
12917 -- entity T in as reasonable state as possible.
12919 --------------------------
12920 -- Fixup_Bad_Constraint --
12921 --------------------------
12923 procedure Fixup_Bad_Constraint is
12925 -- Set a reasonable Ekind for the entity. For an incomplete type,
12926 -- we can't do much, but for other types, we can set the proper
12927 -- corresponding subtype kind.
12929 if Ekind (T) = E_Incomplete_Type then
12930 Set_Ekind (Def_Id, Ekind (T));
12932 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
12935 -- Set Etype to the known type, to reduce chances of cascaded errors
12937 Set_Etype (Def_Id, E);
12938 Set_Error_Posted (Def_Id);
12939 end Fixup_Bad_Constraint;
12941 -- Start of processing for Constrain_Discriminated_Type
12944 C := Constraint (S);
12946 -- A discriminant constraint is only allowed in a subtype indication,
12947 -- after a subtype mark. This subtype mark must denote either a type
12948 -- with discriminants, or an access type whose designated type is a
12949 -- type with discriminants. A discriminant constraint specifies the
12950 -- values of these discriminants (RM 3.7.2(5)).
12952 T := Base_Type (Entity (Subtype_Mark (S)));
12954 if Is_Access_Type (T) then
12955 T := Designated_Type (T);
12958 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
12959 -- Avoid generating an error for access-to-incomplete subtypes.
12961 if Ada_Version >= Ada_2005
12962 and then Ekind (T) = E_Incomplete_Type
12963 and then Nkind (Parent (S)) = N_Subtype_Declaration
12964 and then not Is_Itype (Def_Id)
12966 -- A little sanity check, emit an error message if the type
12967 -- has discriminants to begin with. Type T may be a regular
12968 -- incomplete type or imported via a limited with clause.
12970 if Has_Discriminants (T)
12971 or else (From_Limited_With (T)
12972 and then Present (Non_Limited_View (T))
12973 and then Nkind (Parent (Non_Limited_View (T))) =
12974 N_Full_Type_Declaration
12975 and then Present (Discriminant_Specifications
12976 (Parent (Non_Limited_View (T)))))
12979 ("(Ada 2005) incomplete subtype may not be constrained", C);
12981 Error_Msg_N ("invalid constraint: type has no discriminant", C);
12984 Fixup_Bad_Constraint;
12987 -- Check that the type has visible discriminants. The type may be
12988 -- a private type with unknown discriminants whose full view has
12989 -- discriminants which are invisible.
12991 elsif not Has_Discriminants (T)
12993 (Has_Unknown_Discriminants (T)
12994 and then Is_Private_Type (T))
12996 Error_Msg_N ("invalid constraint: type has no discriminant", C);
12997 Fixup_Bad_Constraint;
13000 elsif Is_Constrained (E)
13001 or else (Ekind (E) = E_Class_Wide_Subtype
13002 and then Present (Discriminant_Constraint (E)))
13004 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
13005 Fixup_Bad_Constraint;
13009 -- T may be an unconstrained subtype (e.g. a generic actual).
13010 -- Constraint applies to the base type.
13012 T := Base_Type (T);
13014 Elist := Build_Discriminant_Constraints (T, S);
13016 -- If the list returned was empty we had an error in building the
13017 -- discriminant constraint. We have also already signalled an error
13018 -- in the incomplete type case
13020 if Is_Empty_Elmt_List (Elist) then
13021 Fixup_Bad_Constraint;
13025 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
13026 end Constrain_Discriminated_Type;
13028 ---------------------------
13029 -- Constrain_Enumeration --
13030 ---------------------------
13032 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
13033 T : constant Entity_Id := Entity (Subtype_Mark (S));
13034 C : constant Node_Id := Constraint (S);
13037 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13039 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
13041 Set_Etype (Def_Id, Base_Type (T));
13042 Set_Size_Info (Def_Id, (T));
13043 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13044 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13046 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13048 Set_Discrete_RM_Size (Def_Id);
13049 end Constrain_Enumeration;
13051 ----------------------
13052 -- Constrain_Float --
13053 ----------------------
13055 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
13056 T : constant Entity_Id := Entity (Subtype_Mark (S));
13062 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
13064 Set_Etype (Def_Id, Base_Type (T));
13065 Set_Size_Info (Def_Id, (T));
13066 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13068 -- Process the constraint
13070 C := Constraint (S);
13072 -- Digits constraint present
13074 if Nkind (C) = N_Digits_Constraint then
13076 Check_SPARK_05_Restriction ("digits constraint is not allowed", S);
13077 Check_Restriction (No_Obsolescent_Features, C);
13079 if Warn_On_Obsolescent_Feature then
13081 ("subtype digits constraint is an " &
13082 "obsolescent feature (RM J.3(8))?j?", C);
13085 D := Digits_Expression (C);
13086 Analyze_And_Resolve (D, Any_Integer);
13087 Check_Digits_Expression (D);
13088 Set_Digits_Value (Def_Id, Expr_Value (D));
13090 -- Check that digits value is in range. Obviously we can do this
13091 -- at compile time, but it is strictly a runtime check, and of
13092 -- course there is an ACVC test that checks this.
13094 if Digits_Value (Def_Id) > Digits_Value (T) then
13095 Error_Msg_Uint_1 := Digits_Value (T);
13096 Error_Msg_N ("??digits value is too large, maximum is ^", D);
13098 Make_Raise_Constraint_Error (Sloc (D),
13099 Reason => CE_Range_Check_Failed);
13100 Insert_Action (Declaration_Node (Def_Id), Rais);
13103 C := Range_Constraint (C);
13105 -- No digits constraint present
13108 Set_Digits_Value (Def_Id, Digits_Value (T));
13111 -- Range constraint present
13113 if Nkind (C) = N_Range_Constraint then
13114 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13116 -- No range constraint present
13119 pragma Assert (No (C));
13120 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13123 Set_Is_Constrained (Def_Id);
13124 end Constrain_Float;
13126 ---------------------
13127 -- Constrain_Index --
13128 ---------------------
13130 procedure Constrain_Index
13133 Related_Nod : Node_Id;
13134 Related_Id : Entity_Id;
13135 Suffix : Character;
13136 Suffix_Index : Nat)
13138 Def_Id : Entity_Id;
13139 R : Node_Id := Empty;
13140 T : constant Entity_Id := Etype (Index);
13143 if Nkind (S) = N_Range
13145 (Nkind (S) = N_Attribute_Reference
13146 and then Attribute_Name (S) = Name_Range)
13148 -- A Range attribute will be transformed into N_Range by Resolve
13154 Process_Range_Expr_In_Decl (R, T);
13156 if not Error_Posted (S)
13158 (Nkind (S) /= N_Range
13159 or else not Covers (T, (Etype (Low_Bound (S))))
13160 or else not Covers (T, (Etype (High_Bound (S)))))
13162 if Base_Type (T) /= Any_Type
13163 and then Etype (Low_Bound (S)) /= Any_Type
13164 and then Etype (High_Bound (S)) /= Any_Type
13166 Error_Msg_N ("range expected", S);
13170 elsif Nkind (S) = N_Subtype_Indication then
13172 -- The parser has verified that this is a discrete indication
13174 Resolve_Discrete_Subtype_Indication (S, T);
13175 Bad_Predicated_Subtype_Use
13176 ("subtype& has predicate, not allowed in index constraint",
13177 S, Entity (Subtype_Mark (S)));
13179 R := Range_Expression (Constraint (S));
13181 -- Capture values of bounds and generate temporaries for them if
13182 -- needed, since checks may cause duplication of the expressions
13183 -- which must not be reevaluated.
13185 -- The forced evaluation removes side effects from expressions, which
13186 -- should occur also in GNATprove mode. Otherwise, we end up with
13187 -- unexpected insertions of actions at places where this is not
13188 -- supposed to occur, e.g. on default parameters of a call.
13190 if Expander_Active or GNATprove_Mode then
13191 Force_Evaluation (Low_Bound (R));
13192 Force_Evaluation (High_Bound (R));
13195 elsif Nkind (S) = N_Discriminant_Association then
13197 -- Syntactically valid in subtype indication
13199 Error_Msg_N ("invalid index constraint", S);
13200 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13203 -- Subtype_Mark case, no anonymous subtypes to construct
13208 if Is_Entity_Name (S) then
13209 if not Is_Type (Entity (S)) then
13210 Error_Msg_N ("expect subtype mark for index constraint", S);
13212 elsif Base_Type (Entity (S)) /= Base_Type (T) then
13213 Wrong_Type (S, Base_Type (T));
13215 -- Check error of subtype with predicate in index constraint
13218 Bad_Predicated_Subtype_Use
13219 ("subtype& has predicate, not allowed in index constraint",
13226 Error_Msg_N ("invalid index constraint", S);
13227 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
13233 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
13235 Set_Etype (Def_Id, Base_Type (T));
13237 if Is_Modular_Integer_Type (T) then
13238 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13240 elsif Is_Integer_Type (T) then
13241 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13244 Set_Ekind (Def_Id, E_Enumeration_Subtype);
13245 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
13246 Set_First_Literal (Def_Id, First_Literal (T));
13249 Set_Size_Info (Def_Id, (T));
13250 Set_RM_Size (Def_Id, RM_Size (T));
13251 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13253 Set_Scalar_Range (Def_Id, R);
13255 Set_Etype (S, Def_Id);
13256 Set_Discrete_RM_Size (Def_Id);
13257 end Constrain_Index;
13259 -----------------------
13260 -- Constrain_Integer --
13261 -----------------------
13263 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
13264 T : constant Entity_Id := Entity (Subtype_Mark (S));
13265 C : constant Node_Id := Constraint (S);
13268 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13270 if Is_Modular_Integer_Type (T) then
13271 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
13273 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
13276 Set_Etype (Def_Id, Base_Type (T));
13277 Set_Size_Info (Def_Id, (T));
13278 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13279 Set_Discrete_RM_Size (Def_Id);
13280 end Constrain_Integer;
13282 ------------------------------
13283 -- Constrain_Ordinary_Fixed --
13284 ------------------------------
13286 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
13287 T : constant Entity_Id := Entity (Subtype_Mark (S));
13293 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
13294 Set_Etype (Def_Id, Base_Type (T));
13295 Set_Size_Info (Def_Id, (T));
13296 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
13297 Set_Small_Value (Def_Id, Small_Value (T));
13299 -- Process the constraint
13301 C := Constraint (S);
13303 -- Delta constraint present
13305 if Nkind (C) = N_Delta_Constraint then
13307 Check_SPARK_05_Restriction ("delta constraint is not allowed", S);
13308 Check_Restriction (No_Obsolescent_Features, C);
13310 if Warn_On_Obsolescent_Feature then
13312 ("subtype delta constraint is an " &
13313 "obsolescent feature (RM J.3(7))?j?");
13316 D := Delta_Expression (C);
13317 Analyze_And_Resolve (D, Any_Real);
13318 Check_Delta_Expression (D);
13319 Set_Delta_Value (Def_Id, Expr_Value_R (D));
13321 -- Check that delta value is in range. Obviously we can do this
13322 -- at compile time, but it is strictly a runtime check, and of
13323 -- course there is an ACVC test that checks this.
13325 if Delta_Value (Def_Id) < Delta_Value (T) then
13326 Error_Msg_N ("??delta value is too small", D);
13328 Make_Raise_Constraint_Error (Sloc (D),
13329 Reason => CE_Range_Check_Failed);
13330 Insert_Action (Declaration_Node (Def_Id), Rais);
13333 C := Range_Constraint (C);
13335 -- No delta constraint present
13338 Set_Delta_Value (Def_Id, Delta_Value (T));
13341 -- Range constraint present
13343 if Nkind (C) = N_Range_Constraint then
13344 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
13346 -- No range constraint present
13349 pragma Assert (No (C));
13350 Set_Scalar_Range (Def_Id, Scalar_Range (T));
13354 Set_Discrete_RM_Size (Def_Id);
13356 -- Unconditionally delay the freeze, since we cannot set size
13357 -- information in all cases correctly until the freeze point.
13359 Set_Has_Delayed_Freeze (Def_Id);
13360 end Constrain_Ordinary_Fixed;
13362 -----------------------
13363 -- Contain_Interface --
13364 -----------------------
13366 function Contain_Interface
13367 (Iface : Entity_Id;
13368 Ifaces : Elist_Id) return Boolean
13370 Iface_Elmt : Elmt_Id;
13373 if Present (Ifaces) then
13374 Iface_Elmt := First_Elmt (Ifaces);
13375 while Present (Iface_Elmt) loop
13376 if Node (Iface_Elmt) = Iface then
13380 Next_Elmt (Iface_Elmt);
13385 end Contain_Interface;
13387 ---------------------------
13388 -- Convert_Scalar_Bounds --
13389 ---------------------------
13391 procedure Convert_Scalar_Bounds
13393 Parent_Type : Entity_Id;
13394 Derived_Type : Entity_Id;
13397 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
13404 -- Defend against previous errors
13406 if No (Scalar_Range (Derived_Type)) then
13407 Check_Error_Detected;
13411 Lo := Build_Scalar_Bound
13412 (Type_Low_Bound (Derived_Type),
13413 Parent_Type, Implicit_Base);
13415 Hi := Build_Scalar_Bound
13416 (Type_High_Bound (Derived_Type),
13417 Parent_Type, Implicit_Base);
13424 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
13426 Set_Parent (Rng, N);
13427 Set_Scalar_Range (Derived_Type, Rng);
13429 -- Analyze the bounds
13431 Analyze_And_Resolve (Lo, Implicit_Base);
13432 Analyze_And_Resolve (Hi, Implicit_Base);
13434 -- Analyze the range itself, except that we do not analyze it if
13435 -- the bounds are real literals, and we have a fixed-point type.
13436 -- The reason for this is that we delay setting the bounds in this
13437 -- case till we know the final Small and Size values (see circuit
13438 -- in Freeze.Freeze_Fixed_Point_Type for further details).
13440 if Is_Fixed_Point_Type (Parent_Type)
13441 and then Nkind (Lo) = N_Real_Literal
13442 and then Nkind (Hi) = N_Real_Literal
13446 -- Here we do the analysis of the range
13448 -- Note: we do this manually, since if we do a normal Analyze and
13449 -- Resolve call, there are problems with the conversions used for
13450 -- the derived type range.
13453 Set_Etype (Rng, Implicit_Base);
13454 Set_Analyzed (Rng, True);
13456 end Convert_Scalar_Bounds;
13458 -------------------
13459 -- Copy_And_Swap --
13460 -------------------
13462 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
13464 -- Initialize new full declaration entity by copying the pertinent
13465 -- fields of the corresponding private declaration entity.
13467 -- We temporarily set Ekind to a value appropriate for a type to
13468 -- avoid assert failures in Einfo from checking for setting type
13469 -- attributes on something that is not a type. Ekind (Priv) is an
13470 -- appropriate choice, since it allowed the attributes to be set
13471 -- in the first place. This Ekind value will be modified later.
13473 Set_Ekind (Full, Ekind (Priv));
13475 -- Also set Etype temporarily to Any_Type, again, in the absence
13476 -- of errors, it will be properly reset, and if there are errors,
13477 -- then we want a value of Any_Type to remain.
13479 Set_Etype (Full, Any_Type);
13481 -- Now start copying attributes
13483 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
13485 if Has_Discriminants (Full) then
13486 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
13487 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
13490 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
13491 Set_Homonym (Full, Homonym (Priv));
13492 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
13493 Set_Is_Public (Full, Is_Public (Priv));
13494 Set_Is_Pure (Full, Is_Pure (Priv));
13495 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
13496 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
13497 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
13498 Set_Has_Pragma_Unreferenced_Objects
13499 (Full, Has_Pragma_Unreferenced_Objects
13502 Conditional_Delay (Full, Priv);
13504 if Is_Tagged_Type (Full) then
13505 Set_Direct_Primitive_Operations
13506 (Full, Direct_Primitive_Operations (Priv));
13507 Set_No_Tagged_Streams_Pragma
13508 (Full, No_Tagged_Streams_Pragma (Priv));
13510 if Is_Base_Type (Priv) then
13511 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
13515 Set_Is_Volatile (Full, Is_Volatile (Priv));
13516 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
13517 Set_Scope (Full, Scope (Priv));
13518 Set_Next_Entity (Full, Next_Entity (Priv));
13519 Set_First_Entity (Full, First_Entity (Priv));
13520 Set_Last_Entity (Full, Last_Entity (Priv));
13522 -- If access types have been recorded for later handling, keep them in
13523 -- the full view so that they get handled when the full view freeze
13524 -- node is expanded.
13526 if Present (Freeze_Node (Priv))
13527 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
13529 Ensure_Freeze_Node (Full);
13530 Set_Access_Types_To_Process
13531 (Freeze_Node (Full),
13532 Access_Types_To_Process (Freeze_Node (Priv)));
13535 -- Swap the two entities. Now Private is the full type entity and Full
13536 -- is the private one. They will be swapped back at the end of the
13537 -- private part. This swapping ensures that the entity that is visible
13538 -- in the private part is the full declaration.
13540 Exchange_Entities (Priv, Full);
13541 Append_Entity (Full, Scope (Full));
13544 -------------------------------------
13545 -- Copy_Array_Base_Type_Attributes --
13546 -------------------------------------
13548 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
13550 Set_Component_Alignment (T1, Component_Alignment (T2));
13551 Set_Component_Type (T1, Component_Type (T2));
13552 Set_Component_Size (T1, Component_Size (T2));
13553 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
13554 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
13555 Set_Has_Protected (T1, Has_Protected (T2));
13556 Set_Has_Task (T1, Has_Task (T2));
13557 Set_Is_Packed (T1, Is_Packed (T2));
13558 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
13559 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
13560 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
13561 end Copy_Array_Base_Type_Attributes;
13563 -----------------------------------
13564 -- Copy_Array_Subtype_Attributes --
13565 -----------------------------------
13567 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
13569 Set_Size_Info (T1, T2);
13571 Set_First_Index (T1, First_Index (T2));
13572 Set_Is_Aliased (T1, Is_Aliased (T2));
13573 Set_Is_Volatile (T1, Is_Volatile (T2));
13574 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
13575 Set_Is_Constrained (T1, Is_Constrained (T2));
13576 Set_Depends_On_Private (T1, Has_Private_Component (T2));
13577 Inherit_Rep_Item_Chain (T1, T2);
13578 Set_Convention (T1, Convention (T2));
13579 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
13580 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
13581 Set_Packed_Array_Impl_Type (T1, Packed_Array_Impl_Type (T2));
13582 end Copy_Array_Subtype_Attributes;
13584 -----------------------------------
13585 -- Create_Constrained_Components --
13586 -----------------------------------
13588 procedure Create_Constrained_Components
13590 Decl_Node : Node_Id;
13592 Constraints : Elist_Id)
13594 Loc : constant Source_Ptr := Sloc (Subt);
13595 Comp_List : constant Elist_Id := New_Elmt_List;
13596 Parent_Type : constant Entity_Id := Etype (Typ);
13597 Assoc_List : constant List_Id := New_List;
13598 Discr_Val : Elmt_Id;
13602 Is_Static : Boolean := True;
13604 procedure Collect_Fixed_Components (Typ : Entity_Id);
13605 -- Collect parent type components that do not appear in a variant part
13607 procedure Create_All_Components;
13608 -- Iterate over Comp_List to create the components of the subtype
13610 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
13611 -- Creates a new component from Old_Compon, copying all the fields from
13612 -- it, including its Etype, inserts the new component in the Subt entity
13613 -- chain and returns the new component.
13615 function Is_Variant_Record (T : Entity_Id) return Boolean;
13616 -- If true, and discriminants are static, collect only components from
13617 -- variants selected by discriminant values.
13619 ------------------------------
13620 -- Collect_Fixed_Components --
13621 ------------------------------
13623 procedure Collect_Fixed_Components (Typ : Entity_Id) is
13625 -- Build association list for discriminants, and find components of the
13626 -- variant part selected by the values of the discriminants.
13628 Old_C := First_Discriminant (Typ);
13629 Discr_Val := First_Elmt (Constraints);
13630 while Present (Old_C) loop
13631 Append_To (Assoc_List,
13632 Make_Component_Association (Loc,
13633 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
13634 Expression => New_Copy (Node (Discr_Val))));
13636 Next_Elmt (Discr_Val);
13637 Next_Discriminant (Old_C);
13640 -- The tag and the possible parent component are unconditionally in
13643 if Is_Tagged_Type (Typ) or else Has_Controlled_Component (Typ) then
13644 Old_C := First_Component (Typ);
13645 while Present (Old_C) loop
13646 if Nam_In (Chars (Old_C), Name_uTag, Name_uParent) then
13647 Append_Elmt (Old_C, Comp_List);
13650 Next_Component (Old_C);
13653 end Collect_Fixed_Components;
13655 ---------------------------
13656 -- Create_All_Components --
13657 ---------------------------
13659 procedure Create_All_Components is
13663 Comp := First_Elmt (Comp_List);
13664 while Present (Comp) loop
13665 Old_C := Node (Comp);
13666 New_C := Create_Component (Old_C);
13670 Constrain_Component_Type
13671 (Old_C, Subt, Decl_Node, Typ, Constraints));
13672 Set_Is_Public (New_C, Is_Public (Subt));
13676 end Create_All_Components;
13678 ----------------------
13679 -- Create_Component --
13680 ----------------------
13682 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
13683 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
13686 if Ekind (Old_Compon) = E_Discriminant
13687 and then Is_Completely_Hidden (Old_Compon)
13689 -- This is a shadow discriminant created for a discriminant of
13690 -- the parent type, which needs to be present in the subtype.
13691 -- Give the shadow discriminant an internal name that cannot
13692 -- conflict with that of visible components.
13694 Set_Chars (New_Compon, New_Internal_Name ('C'));
13697 -- Set the parent so we have a proper link for freezing etc. This is
13698 -- not a real parent pointer, since of course our parent does not own
13699 -- up to us and reference us, we are an illegitimate child of the
13700 -- original parent.
13702 Set_Parent (New_Compon, Parent (Old_Compon));
13704 -- If the old component's Esize was already determined and is a
13705 -- static value, then the new component simply inherits it. Otherwise
13706 -- the old component's size may require run-time determination, but
13707 -- the new component's size still might be statically determinable
13708 -- (if, for example it has a static constraint). In that case we want
13709 -- Layout_Type to recompute the component's size, so we reset its
13710 -- size and positional fields.
13712 if Frontend_Layout_On_Target
13713 and then not Known_Static_Esize (Old_Compon)
13715 Set_Esize (New_Compon, Uint_0);
13716 Init_Normalized_First_Bit (New_Compon);
13717 Init_Normalized_Position (New_Compon);
13718 Init_Normalized_Position_Max (New_Compon);
13721 -- We do not want this node marked as Comes_From_Source, since
13722 -- otherwise it would get first class status and a separate cross-
13723 -- reference line would be generated. Illegitimate children do not
13724 -- rate such recognition.
13726 Set_Comes_From_Source (New_Compon, False);
13728 -- But it is a real entity, and a birth certificate must be properly
13729 -- registered by entering it into the entity list.
13731 Enter_Name (New_Compon);
13734 end Create_Component;
13736 -----------------------
13737 -- Is_Variant_Record --
13738 -----------------------
13740 function Is_Variant_Record (T : Entity_Id) return Boolean is
13742 return Nkind (Parent (T)) = N_Full_Type_Declaration
13743 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
13744 and then Present (Component_List (Type_Definition (Parent (T))))
13747 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
13748 end Is_Variant_Record;
13750 -- Start of processing for Create_Constrained_Components
13753 pragma Assert (Subt /= Base_Type (Subt));
13754 pragma Assert (Typ = Base_Type (Typ));
13756 Set_First_Entity (Subt, Empty);
13757 Set_Last_Entity (Subt, Empty);
13759 -- Check whether constraint is fully static, in which case we can
13760 -- optimize the list of components.
13762 Discr_Val := First_Elmt (Constraints);
13763 while Present (Discr_Val) loop
13764 if not Is_OK_Static_Expression (Node (Discr_Val)) then
13765 Is_Static := False;
13769 Next_Elmt (Discr_Val);
13772 Set_Has_Static_Discriminants (Subt, Is_Static);
13776 -- Inherit the discriminants of the parent type
13778 Add_Discriminants : declare
13784 Old_C := First_Discriminant (Typ);
13786 while Present (Old_C) loop
13787 Num_Disc := Num_Disc + 1;
13788 New_C := Create_Component (Old_C);
13789 Set_Is_Public (New_C, Is_Public (Subt));
13790 Next_Discriminant (Old_C);
13793 -- For an untagged derived subtype, the number of discriminants may
13794 -- be smaller than the number of inherited discriminants, because
13795 -- several of them may be renamed by a single new discriminant or
13796 -- constrained. In this case, add the hidden discriminants back into
13797 -- the subtype, because they need to be present if the optimizer of
13798 -- the GCC 4.x back-end decides to break apart assignments between
13799 -- objects using the parent view into member-wise assignments.
13803 if Is_Derived_Type (Typ)
13804 and then not Is_Tagged_Type (Typ)
13806 Old_C := First_Stored_Discriminant (Typ);
13808 while Present (Old_C) loop
13809 Num_Gird := Num_Gird + 1;
13810 Next_Stored_Discriminant (Old_C);
13814 if Num_Gird > Num_Disc then
13816 -- Find out multiple uses of new discriminants, and add hidden
13817 -- components for the extra renamed discriminants. We recognize
13818 -- multiple uses through the Corresponding_Discriminant of a
13819 -- new discriminant: if it constrains several old discriminants,
13820 -- this field points to the last one in the parent type. The
13821 -- stored discriminants of the derived type have the same name
13822 -- as those of the parent.
13826 New_Discr : Entity_Id;
13827 Old_Discr : Entity_Id;
13830 Constr := First_Elmt (Stored_Constraint (Typ));
13831 Old_Discr := First_Stored_Discriminant (Typ);
13832 while Present (Constr) loop
13833 if Is_Entity_Name (Node (Constr))
13834 and then Ekind (Entity (Node (Constr))) = E_Discriminant
13836 New_Discr := Entity (Node (Constr));
13838 if Chars (Corresponding_Discriminant (New_Discr)) /=
13841 -- The new discriminant has been used to rename a
13842 -- subsequent old discriminant. Introduce a shadow
13843 -- component for the current old discriminant.
13845 New_C := Create_Component (Old_Discr);
13846 Set_Original_Record_Component (New_C, Old_Discr);
13850 -- The constraint has eliminated the old discriminant.
13851 -- Introduce a shadow component.
13853 New_C := Create_Component (Old_Discr);
13854 Set_Original_Record_Component (New_C, Old_Discr);
13857 Next_Elmt (Constr);
13858 Next_Stored_Discriminant (Old_Discr);
13862 end Add_Discriminants;
13865 and then Is_Variant_Record (Typ)
13867 Collect_Fixed_Components (Typ);
13869 Gather_Components (
13871 Component_List (Type_Definition (Parent (Typ))),
13872 Governed_By => Assoc_List,
13874 Report_Errors => Errors);
13875 pragma Assert (not Errors);
13877 Create_All_Components;
13879 -- If the subtype declaration is created for a tagged type derivation
13880 -- with constraints, we retrieve the record definition of the parent
13881 -- type to select the components of the proper variant.
13884 and then Is_Tagged_Type (Typ)
13885 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
13887 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
13888 and then Is_Variant_Record (Parent_Type)
13890 Collect_Fixed_Components (Typ);
13892 Gather_Components (
13894 Component_List (Type_Definition (Parent (Parent_Type))),
13895 Governed_By => Assoc_List,
13897 Report_Errors => Errors);
13898 pragma Assert (not Errors);
13900 -- If the tagged derivation has a type extension, collect all the
13901 -- new components therein.
13904 (Record_Extension_Part (Type_Definition (Parent (Typ))))
13906 Old_C := First_Component (Typ);
13907 while Present (Old_C) loop
13908 if Original_Record_Component (Old_C) = Old_C
13909 and then Chars (Old_C) /= Name_uTag
13910 and then Chars (Old_C) /= Name_uParent
13912 Append_Elmt (Old_C, Comp_List);
13915 Next_Component (Old_C);
13919 Create_All_Components;
13922 -- If discriminants are not static, or if this is a multi-level type
13923 -- extension, we have to include all components of the parent type.
13925 Old_C := First_Component (Typ);
13926 while Present (Old_C) loop
13927 New_C := Create_Component (Old_C);
13931 Constrain_Component_Type
13932 (Old_C, Subt, Decl_Node, Typ, Constraints));
13933 Set_Is_Public (New_C, Is_Public (Subt));
13935 Next_Component (Old_C);
13940 end Create_Constrained_Components;
13942 ------------------------------------------
13943 -- Decimal_Fixed_Point_Type_Declaration --
13944 ------------------------------------------
13946 procedure Decimal_Fixed_Point_Type_Declaration
13950 Loc : constant Source_Ptr := Sloc (Def);
13951 Digs_Expr : constant Node_Id := Digits_Expression (Def);
13952 Delta_Expr : constant Node_Id := Delta_Expression (Def);
13953 Implicit_Base : Entity_Id;
13960 Check_SPARK_05_Restriction
13961 ("decimal fixed point type is not allowed", Def);
13962 Check_Restriction (No_Fixed_Point, Def);
13964 -- Create implicit base type
13967 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
13968 Set_Etype (Implicit_Base, Implicit_Base);
13970 -- Analyze and process delta expression
13972 Analyze_And_Resolve (Delta_Expr, Universal_Real);
13974 Check_Delta_Expression (Delta_Expr);
13975 Delta_Val := Expr_Value_R (Delta_Expr);
13977 -- Check delta is power of 10, and determine scale value from it
13983 Scale_Val := Uint_0;
13986 if Val < Ureal_1 then
13987 while Val < Ureal_1 loop
13988 Val := Val * Ureal_10;
13989 Scale_Val := Scale_Val + 1;
13992 if Scale_Val > 18 then
13993 Error_Msg_N ("scale exceeds maximum value of 18", Def);
13994 Scale_Val := UI_From_Int (+18);
13998 while Val > Ureal_1 loop
13999 Val := Val / Ureal_10;
14000 Scale_Val := Scale_Val - 1;
14003 if Scale_Val < -18 then
14004 Error_Msg_N ("scale is less than minimum value of -18", Def);
14005 Scale_Val := UI_From_Int (-18);
14009 if Val /= Ureal_1 then
14010 Error_Msg_N ("delta expression must be a power of 10", Def);
14011 Delta_Val := Ureal_10 ** (-Scale_Val);
14015 -- Set delta, scale and small (small = delta for decimal type)
14017 Set_Delta_Value (Implicit_Base, Delta_Val);
14018 Set_Scale_Value (Implicit_Base, Scale_Val);
14019 Set_Small_Value (Implicit_Base, Delta_Val);
14021 -- Analyze and process digits expression
14023 Analyze_And_Resolve (Digs_Expr, Any_Integer);
14024 Check_Digits_Expression (Digs_Expr);
14025 Digs_Val := Expr_Value (Digs_Expr);
14027 if Digs_Val > 18 then
14028 Digs_Val := UI_From_Int (+18);
14029 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
14032 Set_Digits_Value (Implicit_Base, Digs_Val);
14033 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
14035 -- Set range of base type from digits value for now. This will be
14036 -- expanded to represent the true underlying base range by Freeze.
14038 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
14040 -- Note: We leave size as zero for now, size will be set at freeze
14041 -- time. We have to do this for ordinary fixed-point, because the size
14042 -- depends on the specified small, and we might as well do the same for
14043 -- decimal fixed-point.
14045 pragma Assert (Esize (Implicit_Base) = Uint_0);
14047 -- If there are bounds given in the declaration use them as the
14048 -- bounds of the first named subtype.
14050 if Present (Real_Range_Specification (Def)) then
14052 RRS : constant Node_Id := Real_Range_Specification (Def);
14053 Low : constant Node_Id := Low_Bound (RRS);
14054 High : constant Node_Id := High_Bound (RRS);
14059 Analyze_And_Resolve (Low, Any_Real);
14060 Analyze_And_Resolve (High, Any_Real);
14061 Check_Real_Bound (Low);
14062 Check_Real_Bound (High);
14063 Low_Val := Expr_Value_R (Low);
14064 High_Val := Expr_Value_R (High);
14066 if Low_Val < (-Bound_Val) then
14068 ("range low bound too small for digits value", Low);
14069 Low_Val := -Bound_Val;
14072 if High_Val > Bound_Val then
14074 ("range high bound too large for digits value", High);
14075 High_Val := Bound_Val;
14078 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
14081 -- If no explicit range, use range that corresponds to given
14082 -- digits value. This will end up as the final range for the
14086 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
14089 -- Complete entity for first subtype. The inheritance of the rep item
14090 -- chain ensures that SPARK-related pragmas are not clobbered when the
14091 -- decimal fixed point type acts as a full view of a private type.
14093 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
14094 Set_Etype (T, Implicit_Base);
14095 Set_Size_Info (T, Implicit_Base);
14096 Inherit_Rep_Item_Chain (T, Implicit_Base);
14097 Set_Digits_Value (T, Digs_Val);
14098 Set_Delta_Value (T, Delta_Val);
14099 Set_Small_Value (T, Delta_Val);
14100 Set_Scale_Value (T, Scale_Val);
14101 Set_Is_Constrained (T);
14102 end Decimal_Fixed_Point_Type_Declaration;
14104 -----------------------------------
14105 -- Derive_Progenitor_Subprograms --
14106 -----------------------------------
14108 procedure Derive_Progenitor_Subprograms
14109 (Parent_Type : Entity_Id;
14110 Tagged_Type : Entity_Id)
14115 Iface_Elmt : Elmt_Id;
14116 Iface_Subp : Entity_Id;
14117 New_Subp : Entity_Id := Empty;
14118 Prim_Elmt : Elmt_Id;
14123 pragma Assert (Ada_Version >= Ada_2005
14124 and then Is_Record_Type (Tagged_Type)
14125 and then Is_Tagged_Type (Tagged_Type)
14126 and then Has_Interfaces (Tagged_Type));
14128 -- Step 1: Transfer to the full-view primitives associated with the
14129 -- partial-view that cover interface primitives. Conceptually this
14130 -- work should be done later by Process_Full_View; done here to
14131 -- simplify its implementation at later stages. It can be safely
14132 -- done here because interfaces must be visible in the partial and
14133 -- private view (RM 7.3(7.3/2)).
14135 -- Small optimization: This work is only required if the parent may
14136 -- have entities whose Alias attribute reference an interface primitive.
14137 -- Such a situation may occur if the parent is an abstract type and the
14138 -- primitive has not been yet overridden or if the parent is a generic
14139 -- formal type covering interfaces.
14141 -- If the tagged type is not abstract, it cannot have abstract
14142 -- primitives (the only entities in the list of primitives of
14143 -- non-abstract tagged types that can reference abstract primitives
14144 -- through its Alias attribute are the internal entities that have
14145 -- attribute Interface_Alias, and these entities are generated later
14146 -- by Add_Internal_Interface_Entities).
14148 if In_Private_Part (Current_Scope)
14149 and then (Is_Abstract_Type (Parent_Type)
14151 Is_Generic_Type (Parent_Type))
14153 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
14154 while Present (Elmt) loop
14155 Subp := Node (Elmt);
14157 -- At this stage it is not possible to have entities in the list
14158 -- of primitives that have attribute Interface_Alias.
14160 pragma Assert (No (Interface_Alias (Subp)));
14162 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
14164 if Is_Interface (Typ) then
14165 E := Find_Primitive_Covering_Interface
14166 (Tagged_Type => Tagged_Type,
14167 Iface_Prim => Subp);
14170 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
14172 Replace_Elmt (Elmt, E);
14173 Remove_Homonym (Subp);
14181 -- Step 2: Add primitives of progenitors that are not implemented by
14182 -- parents of Tagged_Type.
14184 if Present (Interfaces (Base_Type (Tagged_Type))) then
14185 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
14186 while Present (Iface_Elmt) loop
14187 Iface := Node (Iface_Elmt);
14189 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
14190 while Present (Prim_Elmt) loop
14191 Iface_Subp := Node (Prim_Elmt);
14193 -- Exclude derivation of predefined primitives except those
14194 -- that come from source, or are inherited from one that comes
14195 -- from source. Required to catch declarations of equality
14196 -- operators of interfaces. For example:
14198 -- type Iface is interface;
14199 -- function "=" (Left, Right : Iface) return Boolean;
14201 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
14202 or else Comes_From_Source (Ultimate_Alias (Iface_Subp))
14204 E := Find_Primitive_Covering_Interface
14205 (Tagged_Type => Tagged_Type,
14206 Iface_Prim => Iface_Subp);
14208 -- If not found we derive a new primitive leaving its alias
14209 -- attribute referencing the interface primitive.
14213 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14215 -- Ada 2012 (AI05-0197): If the covering primitive's name
14216 -- differs from the name of the interface primitive then it
14217 -- is a private primitive inherited from a parent type. In
14218 -- such case, given that Tagged_Type covers the interface,
14219 -- the inherited private primitive becomes visible. For such
14220 -- purpose we add a new entity that renames the inherited
14221 -- private primitive.
14223 elsif Chars (E) /= Chars (Iface_Subp) then
14224 pragma Assert (Has_Suffix (E, 'P'));
14226 (New_Subp, Iface_Subp, Tagged_Type, Iface);
14227 Set_Alias (New_Subp, E);
14228 Set_Is_Abstract_Subprogram (New_Subp,
14229 Is_Abstract_Subprogram (E));
14231 -- Propagate to the full view interface entities associated
14232 -- with the partial view.
14234 elsif In_Private_Part (Current_Scope)
14235 and then Present (Alias (E))
14236 and then Alias (E) = Iface_Subp
14238 List_Containing (Parent (E)) /=
14239 Private_Declarations
14241 (Unit_Declaration_Node (Current_Scope)))
14243 Append_Elmt (E, Primitive_Operations (Tagged_Type));
14247 Next_Elmt (Prim_Elmt);
14250 Next_Elmt (Iface_Elmt);
14253 end Derive_Progenitor_Subprograms;
14255 -----------------------
14256 -- Derive_Subprogram --
14257 -----------------------
14259 procedure Derive_Subprogram
14260 (New_Subp : in out Entity_Id;
14261 Parent_Subp : Entity_Id;
14262 Derived_Type : Entity_Id;
14263 Parent_Type : Entity_Id;
14264 Actual_Subp : Entity_Id := Empty)
14266 Formal : Entity_Id;
14267 -- Formal parameter of parent primitive operation
14269 Formal_Of_Actual : Entity_Id;
14270 -- Formal parameter of actual operation, when the derivation is to
14271 -- create a renaming for a primitive operation of an actual in an
14274 New_Formal : Entity_Id;
14275 -- Formal of inherited operation
14277 Visible_Subp : Entity_Id := Parent_Subp;
14279 function Is_Private_Overriding return Boolean;
14280 -- If Subp is a private overriding of a visible operation, the inherited
14281 -- operation derives from the overridden op (even though its body is the
14282 -- overriding one) and the inherited operation is visible now. See
14283 -- sem_disp to see the full details of the handling of the overridden
14284 -- subprogram, which is removed from the list of primitive operations of
14285 -- the type. The overridden subprogram is saved locally in Visible_Subp,
14286 -- and used to diagnose abstract operations that need overriding in the
14289 procedure Replace_Type (Id, New_Id : Entity_Id);
14290 -- When the type is an anonymous access type, create a new access type
14291 -- designating the derived type.
14293 procedure Set_Derived_Name;
14294 -- This procedure sets the appropriate Chars name for New_Subp. This
14295 -- is normally just a copy of the parent name. An exception arises for
14296 -- type support subprograms, where the name is changed to reflect the
14297 -- name of the derived type, e.g. if type foo is derived from type bar,
14298 -- then a procedure barDA is derived with a name fooDA.
14300 ---------------------------
14301 -- Is_Private_Overriding --
14302 ---------------------------
14304 function Is_Private_Overriding return Boolean is
14308 -- If the parent is not a dispatching operation there is no
14309 -- need to investigate overridings
14311 if not Is_Dispatching_Operation (Parent_Subp) then
14315 -- The visible operation that is overridden is a homonym of the
14316 -- parent subprogram. We scan the homonym chain to find the one
14317 -- whose alias is the subprogram we are deriving.
14319 Prev := Current_Entity (Parent_Subp);
14320 while Present (Prev) loop
14321 if Ekind (Prev) = Ekind (Parent_Subp)
14322 and then Alias (Prev) = Parent_Subp
14323 and then Scope (Parent_Subp) = Scope (Prev)
14324 and then not Is_Hidden (Prev)
14326 Visible_Subp := Prev;
14330 Prev := Homonym (Prev);
14334 end Is_Private_Overriding;
14340 procedure Replace_Type (Id, New_Id : Entity_Id) is
14341 Id_Type : constant Entity_Id := Etype (Id);
14342 Acc_Type : Entity_Id;
14343 Par : constant Node_Id := Parent (Derived_Type);
14346 -- When the type is an anonymous access type, create a new access
14347 -- type designating the derived type. This itype must be elaborated
14348 -- at the point of the derivation, not on subsequent calls that may
14349 -- be out of the proper scope for Gigi, so we insert a reference to
14350 -- it after the derivation.
14352 if Ekind (Id_Type) = E_Anonymous_Access_Type then
14354 Desig_Typ : Entity_Id := Designated_Type (Id_Type);
14357 if Ekind (Desig_Typ) = E_Record_Type_With_Private
14358 and then Present (Full_View (Desig_Typ))
14359 and then not Is_Private_Type (Parent_Type)
14361 Desig_Typ := Full_View (Desig_Typ);
14364 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
14366 -- Ada 2005 (AI-251): Handle also derivations of abstract
14367 -- interface primitives.
14369 or else (Is_Interface (Desig_Typ)
14370 and then not Is_Class_Wide_Type (Desig_Typ))
14372 Acc_Type := New_Copy (Id_Type);
14373 Set_Etype (Acc_Type, Acc_Type);
14374 Set_Scope (Acc_Type, New_Subp);
14376 -- Set size of anonymous access type. If we have an access
14377 -- to an unconstrained array, this is a fat pointer, so it
14378 -- is sizes at twice addtress size.
14380 if Is_Array_Type (Desig_Typ)
14381 and then not Is_Constrained (Desig_Typ)
14383 Init_Size (Acc_Type, 2 * System_Address_Size);
14385 -- Other cases use a thin pointer
14388 Init_Size (Acc_Type, System_Address_Size);
14391 -- Set remaining characterstics of anonymous access type
14393 Init_Alignment (Acc_Type);
14394 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
14396 Set_Etype (New_Id, Acc_Type);
14397 Set_Scope (New_Id, New_Subp);
14399 -- Create a reference to it
14401 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
14404 Set_Etype (New_Id, Id_Type);
14408 -- In Ada2012, a formal may have an incomplete type but the type
14409 -- derivation that inherits the primitive follows the full view.
14411 elsif Base_Type (Id_Type) = Base_Type (Parent_Type)
14413 (Ekind (Id_Type) = E_Record_Type_With_Private
14414 and then Present (Full_View (Id_Type))
14416 Base_Type (Full_View (Id_Type)) = Base_Type (Parent_Type))
14418 (Ada_Version >= Ada_2012
14419 and then Ekind (Id_Type) = E_Incomplete_Type
14420 and then Full_View (Id_Type) = Parent_Type)
14422 -- Constraint checks on formals are generated during expansion,
14423 -- based on the signature of the original subprogram. The bounds
14424 -- of the derived type are not relevant, and thus we can use
14425 -- the base type for the formals. However, the return type may be
14426 -- used in a context that requires that the proper static bounds
14427 -- be used (a case statement, for example) and for those cases
14428 -- we must use the derived type (first subtype), not its base.
14430 -- If the derived_type_definition has no constraints, we know that
14431 -- the derived type has the same constraints as the first subtype
14432 -- of the parent, and we can also use it rather than its base,
14433 -- which can lead to more efficient code.
14435 if Etype (Id) = Parent_Type then
14436 if Is_Scalar_Type (Parent_Type)
14438 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
14440 Set_Etype (New_Id, Derived_Type);
14442 elsif Nkind (Par) = N_Full_Type_Declaration
14444 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
14447 (Subtype_Indication (Type_Definition (Par)))
14449 Set_Etype (New_Id, Derived_Type);
14452 Set_Etype (New_Id, Base_Type (Derived_Type));
14456 Set_Etype (New_Id, Base_Type (Derived_Type));
14460 Set_Etype (New_Id, Etype (Id));
14464 ----------------------
14465 -- Set_Derived_Name --
14466 ----------------------
14468 procedure Set_Derived_Name is
14469 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
14471 if Nm = TSS_Null then
14472 Set_Chars (New_Subp, Chars (Parent_Subp));
14474 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
14476 end Set_Derived_Name;
14478 -- Start of processing for Derive_Subprogram
14481 New_Subp := New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
14482 Set_Ekind (New_Subp, Ekind (Parent_Subp));
14483 Set_Contract (New_Subp, Make_Contract (Sloc (New_Subp)));
14485 -- Check whether the inherited subprogram is a private operation that
14486 -- should be inherited but not yet made visible. Such subprograms can
14487 -- become visible at a later point (e.g., the private part of a public
14488 -- child unit) via Declare_Inherited_Private_Subprograms. If the
14489 -- following predicate is true, then this is not such a private
14490 -- operation and the subprogram simply inherits the name of the parent
14491 -- subprogram. Note the special check for the names of controlled
14492 -- operations, which are currently exempted from being inherited with
14493 -- a hidden name because they must be findable for generation of
14494 -- implicit run-time calls.
14496 if not Is_Hidden (Parent_Subp)
14497 or else Is_Internal (Parent_Subp)
14498 or else Is_Private_Overriding
14499 or else Is_Internal_Name (Chars (Parent_Subp))
14500 or else Nam_In (Chars (Parent_Subp), Name_Initialize,
14506 -- An inherited dispatching equality will be overridden by an internally
14507 -- generated one, or by an explicit one, so preserve its name and thus
14508 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
14509 -- private operation it may become invisible if the full view has
14510 -- progenitors, and the dispatch table will be malformed.
14511 -- We check that the type is limited to handle the anomalous declaration
14512 -- of Limited_Controlled, which is derived from a non-limited type, and
14513 -- which is handled specially elsewhere as well.
14515 elsif Chars (Parent_Subp) = Name_Op_Eq
14516 and then Is_Dispatching_Operation (Parent_Subp)
14517 and then Etype (Parent_Subp) = Standard_Boolean
14518 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
14520 Etype (First_Formal (Parent_Subp)) =
14521 Etype (Next_Formal (First_Formal (Parent_Subp)))
14525 -- If parent is hidden, this can be a regular derivation if the
14526 -- parent is immediately visible in a non-instantiating context,
14527 -- or if we are in the private part of an instance. This test
14528 -- should still be refined ???
14530 -- The test for In_Instance_Not_Visible avoids inheriting the derived
14531 -- operation as a non-visible operation in cases where the parent
14532 -- subprogram might not be visible now, but was visible within the
14533 -- original generic, so it would be wrong to make the inherited
14534 -- subprogram non-visible now. (Not clear if this test is fully
14535 -- correct; are there any cases where we should declare the inherited
14536 -- operation as not visible to avoid it being overridden, e.g., when
14537 -- the parent type is a generic actual with private primitives ???)
14539 -- (they should be treated the same as other private inherited
14540 -- subprograms, but it's not clear how to do this cleanly). ???
14542 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
14543 and then Is_Immediately_Visible (Parent_Subp)
14544 and then not In_Instance)
14545 or else In_Instance_Not_Visible
14549 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
14550 -- overrides an interface primitive because interface primitives
14551 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
14553 elsif Ada_Version >= Ada_2005
14554 and then Is_Dispatching_Operation (Parent_Subp)
14555 and then Covers_Some_Interface (Parent_Subp)
14559 -- Otherwise, the type is inheriting a private operation, so enter
14560 -- it with a special name so it can't be overridden.
14563 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
14566 Set_Parent (New_Subp, Parent (Derived_Type));
14568 if Present (Actual_Subp) then
14569 Replace_Type (Actual_Subp, New_Subp);
14571 Replace_Type (Parent_Subp, New_Subp);
14574 Conditional_Delay (New_Subp, Parent_Subp);
14576 -- If we are creating a renaming for a primitive operation of an
14577 -- actual of a generic derived type, we must examine the signature
14578 -- of the actual primitive, not that of the generic formal, which for
14579 -- example may be an interface. However the name and initial value
14580 -- of the inherited operation are those of the formal primitive.
14582 Formal := First_Formal (Parent_Subp);
14584 if Present (Actual_Subp) then
14585 Formal_Of_Actual := First_Formal (Actual_Subp);
14587 Formal_Of_Actual := Empty;
14590 while Present (Formal) loop
14591 New_Formal := New_Copy (Formal);
14593 -- Normally we do not go copying parents, but in the case of
14594 -- formals, we need to link up to the declaration (which is the
14595 -- parameter specification), and it is fine to link up to the
14596 -- original formal's parameter specification in this case.
14598 Set_Parent (New_Formal, Parent (Formal));
14599 Append_Entity (New_Formal, New_Subp);
14601 if Present (Formal_Of_Actual) then
14602 Replace_Type (Formal_Of_Actual, New_Formal);
14603 Next_Formal (Formal_Of_Actual);
14605 Replace_Type (Formal, New_Formal);
14608 Next_Formal (Formal);
14611 -- If this derivation corresponds to a tagged generic actual, then
14612 -- primitive operations rename those of the actual. Otherwise the
14613 -- primitive operations rename those of the parent type, If the parent
14614 -- renames an intrinsic operator, so does the new subprogram. We except
14615 -- concatenation, which is always properly typed, and does not get
14616 -- expanded as other intrinsic operations.
14618 if No (Actual_Subp) then
14619 if Is_Intrinsic_Subprogram (Parent_Subp) then
14620 Set_Is_Intrinsic_Subprogram (New_Subp);
14622 if Present (Alias (Parent_Subp))
14623 and then Chars (Parent_Subp) /= Name_Op_Concat
14625 Set_Alias (New_Subp, Alias (Parent_Subp));
14627 Set_Alias (New_Subp, Parent_Subp);
14631 Set_Alias (New_Subp, Parent_Subp);
14635 Set_Alias (New_Subp, Actual_Subp);
14638 -- Derived subprograms of a tagged type must inherit the convention
14639 -- of the parent subprogram (a requirement of AI-117). Derived
14640 -- subprograms of untagged types simply get convention Ada by default.
14642 -- If the derived type is a tagged generic formal type with unknown
14643 -- discriminants, its convention is intrinsic (RM 6.3.1 (8)).
14645 -- However, if the type is derived from a generic formal, the further
14646 -- inherited subprogram has the convention of the non-generic ancestor.
14647 -- Otherwise there would be no way to override the operation.
14648 -- (This is subject to forthcoming ARG discussions).
14650 if Is_Tagged_Type (Derived_Type) then
14651 if Is_Generic_Type (Derived_Type)
14652 and then Has_Unknown_Discriminants (Derived_Type)
14654 Set_Convention (New_Subp, Convention_Intrinsic);
14657 if Is_Generic_Type (Parent_Type)
14658 and then Has_Unknown_Discriminants (Parent_Type)
14660 Set_Convention (New_Subp, Convention (Alias (Parent_Subp)));
14662 Set_Convention (New_Subp, Convention (Parent_Subp));
14667 -- Predefined controlled operations retain their name even if the parent
14668 -- is hidden (see above), but they are not primitive operations if the
14669 -- ancestor is not visible, for example if the parent is a private
14670 -- extension completed with a controlled extension. Note that a full
14671 -- type that is controlled can break privacy: the flag Is_Controlled is
14672 -- set on both views of the type.
14674 if Is_Controlled (Parent_Type)
14675 and then Nam_In (Chars (Parent_Subp), Name_Initialize,
14678 and then Is_Hidden (Parent_Subp)
14679 and then not Is_Visibly_Controlled (Parent_Type)
14681 Set_Is_Hidden (New_Subp);
14684 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
14685 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
14687 if Ekind (Parent_Subp) = E_Procedure then
14688 Set_Is_Valued_Procedure
14689 (New_Subp, Is_Valued_Procedure (Parent_Subp));
14691 Set_Has_Controlling_Result
14692 (New_Subp, Has_Controlling_Result (Parent_Subp));
14695 -- No_Return must be inherited properly. If this is overridden in the
14696 -- case of a dispatching operation, then a check is made in Sem_Disp
14697 -- that the overriding operation is also No_Return (no such check is
14698 -- required for the case of non-dispatching operation.
14700 Set_No_Return (New_Subp, No_Return (Parent_Subp));
14702 -- A derived function with a controlling result is abstract. If the
14703 -- Derived_Type is a nonabstract formal generic derived type, then
14704 -- inherited operations are not abstract: the required check is done at
14705 -- instantiation time. If the derivation is for a generic actual, the
14706 -- function is not abstract unless the actual is.
14708 if Is_Generic_Type (Derived_Type)
14709 and then not Is_Abstract_Type (Derived_Type)
14713 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
14714 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
14716 -- A subprogram subject to pragma Extensions_Visible with value False
14717 -- requires overriding if the subprogram has at least one controlling
14718 -- OUT parameter (SPARK RM 6.1.7(6)).
14720 elsif Ada_Version >= Ada_2005
14721 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14722 or else (Is_Tagged_Type (Derived_Type)
14723 and then Etype (New_Subp) = Derived_Type
14724 and then not Is_Null_Extension (Derived_Type))
14725 or else (Is_Tagged_Type (Derived_Type)
14726 and then Ekind (Etype (New_Subp)) =
14727 E_Anonymous_Access_Type
14728 and then Designated_Type (Etype (New_Subp)) =
14730 and then not Is_Null_Extension (Derived_Type))
14731 or else (Comes_From_Source (Alias (New_Subp))
14732 and then Is_EVF_Procedure (Alias (New_Subp))))
14733 and then No (Actual_Subp)
14735 if not Is_Tagged_Type (Derived_Type)
14736 or else Is_Abstract_Type (Derived_Type)
14737 or else Is_Abstract_Subprogram (Alias (New_Subp))
14739 Set_Is_Abstract_Subprogram (New_Subp);
14741 Set_Requires_Overriding (New_Subp);
14744 elsif Ada_Version < Ada_2005
14745 and then (Is_Abstract_Subprogram (Alias (New_Subp))
14746 or else (Is_Tagged_Type (Derived_Type)
14747 and then Etype (New_Subp) = Derived_Type
14748 and then No (Actual_Subp)))
14750 Set_Is_Abstract_Subprogram (New_Subp);
14752 -- AI05-0097 : an inherited operation that dispatches on result is
14753 -- abstract if the derived type is abstract, even if the parent type
14754 -- is concrete and the derived type is a null extension.
14756 elsif Has_Controlling_Result (Alias (New_Subp))
14757 and then Is_Abstract_Type (Etype (New_Subp))
14759 Set_Is_Abstract_Subprogram (New_Subp);
14761 -- Finally, if the parent type is abstract we must verify that all
14762 -- inherited operations are either non-abstract or overridden, or that
14763 -- the derived type itself is abstract (this check is performed at the
14764 -- end of a package declaration, in Check_Abstract_Overriding). A
14765 -- private overriding in the parent type will not be visible in the
14766 -- derivation if we are not in an inner package or in a child unit of
14767 -- the parent type, in which case the abstractness of the inherited
14768 -- operation is carried to the new subprogram.
14770 elsif Is_Abstract_Type (Parent_Type)
14771 and then not In_Open_Scopes (Scope (Parent_Type))
14772 and then Is_Private_Overriding
14773 and then Is_Abstract_Subprogram (Visible_Subp)
14775 if No (Actual_Subp) then
14776 Set_Alias (New_Subp, Visible_Subp);
14777 Set_Is_Abstract_Subprogram (New_Subp, True);
14780 -- If this is a derivation for an instance of a formal derived
14781 -- type, abstractness comes from the primitive operation of the
14782 -- actual, not from the operation inherited from the ancestor.
14784 Set_Is_Abstract_Subprogram
14785 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
14789 New_Overloaded_Entity (New_Subp, Derived_Type);
14791 -- Check for case of a derived subprogram for the instantiation of a
14792 -- formal derived tagged type, if so mark the subprogram as dispatching
14793 -- and inherit the dispatching attributes of the actual subprogram. The
14794 -- derived subprogram is effectively renaming of the actual subprogram,
14795 -- so it needs to have the same attributes as the actual.
14797 if Present (Actual_Subp)
14798 and then Is_Dispatching_Operation (Actual_Subp)
14800 Set_Is_Dispatching_Operation (New_Subp);
14802 if Present (DTC_Entity (Actual_Subp)) then
14803 Set_DTC_Entity (New_Subp, DTC_Entity (Actual_Subp));
14804 Set_DT_Position (New_Subp, DT_Position (Actual_Subp));
14808 -- Indicate that a derived subprogram does not require a body and that
14809 -- it does not require processing of default expressions.
14811 Set_Has_Completion (New_Subp);
14812 Set_Default_Expressions_Processed (New_Subp);
14814 if Ekind (New_Subp) = E_Function then
14815 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
14817 end Derive_Subprogram;
14819 ------------------------
14820 -- Derive_Subprograms --
14821 ------------------------
14823 procedure Derive_Subprograms
14824 (Parent_Type : Entity_Id;
14825 Derived_Type : Entity_Id;
14826 Generic_Actual : Entity_Id := Empty)
14828 Op_List : constant Elist_Id :=
14829 Collect_Primitive_Operations (Parent_Type);
14831 function Check_Derived_Type return Boolean;
14832 -- Check that all the entities derived from Parent_Type are found in
14833 -- the list of primitives of Derived_Type exactly in the same order.
14835 procedure Derive_Interface_Subprogram
14836 (New_Subp : in out Entity_Id;
14838 Actual_Subp : Entity_Id);
14839 -- Derive New_Subp from the ultimate alias of the parent subprogram Subp
14840 -- (which is an interface primitive). If Generic_Actual is present then
14841 -- Actual_Subp is the actual subprogram corresponding with the generic
14842 -- subprogram Subp.
14844 function Check_Derived_Type return Boolean is
14848 New_Subp : Entity_Id;
14853 -- Traverse list of entities in the current scope searching for
14854 -- an incomplete type whose full-view is derived type
14856 E := First_Entity (Scope (Derived_Type));
14857 while Present (E) and then E /= Derived_Type loop
14858 if Ekind (E) = E_Incomplete_Type
14859 and then Present (Full_View (E))
14860 and then Full_View (E) = Derived_Type
14862 -- Disable this test if Derived_Type completes an incomplete
14863 -- type because in such case more primitives can be added
14864 -- later to the list of primitives of Derived_Type by routine
14865 -- Process_Incomplete_Dependents
14870 E := Next_Entity (E);
14873 List := Collect_Primitive_Operations (Derived_Type);
14874 Elmt := First_Elmt (List);
14876 Op_Elmt := First_Elmt (Op_List);
14877 while Present (Op_Elmt) loop
14878 Subp := Node (Op_Elmt);
14879 New_Subp := Node (Elmt);
14881 -- At this early stage Derived_Type has no entities with attribute
14882 -- Interface_Alias. In addition, such primitives are always
14883 -- located at the end of the list of primitives of Parent_Type.
14884 -- Therefore, if found we can safely stop processing pending
14887 exit when Present (Interface_Alias (Subp));
14889 -- Handle hidden entities
14891 if not Is_Predefined_Dispatching_Operation (Subp)
14892 and then Is_Hidden (Subp)
14894 if Present (New_Subp)
14895 and then Primitive_Names_Match (Subp, New_Subp)
14901 if not Present (New_Subp)
14902 or else Ekind (Subp) /= Ekind (New_Subp)
14903 or else not Primitive_Names_Match (Subp, New_Subp)
14911 Next_Elmt (Op_Elmt);
14915 end Check_Derived_Type;
14917 ---------------------------------
14918 -- Derive_Interface_Subprogram --
14919 ---------------------------------
14921 procedure Derive_Interface_Subprogram
14922 (New_Subp : in out Entity_Id;
14924 Actual_Subp : Entity_Id)
14926 Iface_Subp : constant Entity_Id := Ultimate_Alias (Subp);
14927 Iface_Type : constant Entity_Id := Find_Dispatching_Type (Iface_Subp);
14930 pragma Assert (Is_Interface (Iface_Type));
14933 (New_Subp => New_Subp,
14934 Parent_Subp => Iface_Subp,
14935 Derived_Type => Derived_Type,
14936 Parent_Type => Iface_Type,
14937 Actual_Subp => Actual_Subp);
14939 -- Given that this new interface entity corresponds with a primitive
14940 -- of the parent that was not overridden we must leave it associated
14941 -- with its parent primitive to ensure that it will share the same
14942 -- dispatch table slot when overridden.
14944 if No (Actual_Subp) then
14945 Set_Alias (New_Subp, Subp);
14947 -- For instantiations this is not needed since the previous call to
14948 -- Derive_Subprogram leaves the entity well decorated.
14951 pragma Assert (Alias (New_Subp) = Actual_Subp);
14954 end Derive_Interface_Subprogram;
14958 Alias_Subp : Entity_Id;
14959 Act_List : Elist_Id;
14960 Act_Elmt : Elmt_Id;
14961 Act_Subp : Entity_Id := Empty;
14963 Need_Search : Boolean := False;
14964 New_Subp : Entity_Id := Empty;
14965 Parent_Base : Entity_Id;
14968 -- Start of processing for Derive_Subprograms
14971 if Ekind (Parent_Type) = E_Record_Type_With_Private
14972 and then Has_Discriminants (Parent_Type)
14973 and then Present (Full_View (Parent_Type))
14975 Parent_Base := Full_View (Parent_Type);
14977 Parent_Base := Parent_Type;
14980 if Present (Generic_Actual) then
14981 Act_List := Collect_Primitive_Operations (Generic_Actual);
14982 Act_Elmt := First_Elmt (Act_List);
14984 Act_List := No_Elist;
14985 Act_Elmt := No_Elmt;
14988 -- Derive primitives inherited from the parent. Note that if the generic
14989 -- actual is present, this is not really a type derivation, it is a
14990 -- completion within an instance.
14992 -- Case 1: Derived_Type does not implement interfaces
14994 if not Is_Tagged_Type (Derived_Type)
14995 or else (not Has_Interfaces (Derived_Type)
14996 and then not (Present (Generic_Actual)
14997 and then Has_Interfaces (Generic_Actual)))
14999 Elmt := First_Elmt (Op_List);
15000 while Present (Elmt) loop
15001 Subp := Node (Elmt);
15003 -- Literals are derived earlier in the process of building the
15004 -- derived type, and are skipped here.
15006 if Ekind (Subp) = E_Enumeration_Literal then
15009 -- The actual is a direct descendant and the common primitive
15010 -- operations appear in the same order.
15012 -- If the generic parent type is present, the derived type is an
15013 -- instance of a formal derived type, and within the instance its
15014 -- operations are those of the actual. We derive from the formal
15015 -- type but make the inherited operations aliases of the
15016 -- corresponding operations of the actual.
15019 pragma Assert (No (Node (Act_Elmt))
15020 or else (Primitive_Names_Match (Subp, Node (Act_Elmt))
15023 (Subp, Node (Act_Elmt),
15024 Skip_Controlling_Formals => True)));
15027 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
15029 if Present (Act_Elmt) then
15030 Next_Elmt (Act_Elmt);
15037 -- Case 2: Derived_Type implements interfaces
15040 -- If the parent type has no predefined primitives we remove
15041 -- predefined primitives from the list of primitives of generic
15042 -- actual to simplify the complexity of this algorithm.
15044 if Present (Generic_Actual) then
15046 Has_Predefined_Primitives : Boolean := False;
15049 -- Check if the parent type has predefined primitives
15051 Elmt := First_Elmt (Op_List);
15052 while Present (Elmt) loop
15053 Subp := Node (Elmt);
15055 if Is_Predefined_Dispatching_Operation (Subp)
15056 and then not Comes_From_Source (Ultimate_Alias (Subp))
15058 Has_Predefined_Primitives := True;
15065 -- Remove predefined primitives of Generic_Actual. We must use
15066 -- an auxiliary list because in case of tagged types the value
15067 -- returned by Collect_Primitive_Operations is the value stored
15068 -- in its Primitive_Operations attribute (and we don't want to
15069 -- modify its current contents).
15071 if not Has_Predefined_Primitives then
15073 Aux_List : constant Elist_Id := New_Elmt_List;
15076 Elmt := First_Elmt (Act_List);
15077 while Present (Elmt) loop
15078 Subp := Node (Elmt);
15080 if not Is_Predefined_Dispatching_Operation (Subp)
15081 or else Comes_From_Source (Subp)
15083 Append_Elmt (Subp, Aux_List);
15089 Act_List := Aux_List;
15093 Act_Elmt := First_Elmt (Act_List);
15094 Act_Subp := Node (Act_Elmt);
15098 -- Stage 1: If the generic actual is not present we derive the
15099 -- primitives inherited from the parent type. If the generic parent
15100 -- type is present, the derived type is an instance of a formal
15101 -- derived type, and within the instance its operations are those of
15102 -- the actual. We derive from the formal type but make the inherited
15103 -- operations aliases of the corresponding operations of the actual.
15105 Elmt := First_Elmt (Op_List);
15106 while Present (Elmt) loop
15107 Subp := Node (Elmt);
15108 Alias_Subp := Ultimate_Alias (Subp);
15110 -- Do not derive internal entities of the parent that link
15111 -- interface primitives with their covering primitive. These
15112 -- entities will be added to this type when frozen.
15114 if Present (Interface_Alias (Subp)) then
15118 -- If the generic actual is present find the corresponding
15119 -- operation in the generic actual. If the parent type is a
15120 -- direct ancestor of the derived type then, even if it is an
15121 -- interface, the operations are inherited from the primary
15122 -- dispatch table and are in the proper order. If we detect here
15123 -- that primitives are not in the same order we traverse the list
15124 -- of primitive operations of the actual to find the one that
15125 -- implements the interface primitive.
15129 (Present (Generic_Actual)
15130 and then Present (Act_Subp)
15132 (Primitive_Names_Match (Subp, Act_Subp)
15134 Type_Conformant (Subp, Act_Subp,
15135 Skip_Controlling_Formals => True)))
15137 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual,
15138 Use_Full_View => True));
15140 -- Remember that we need searching for all pending primitives
15142 Need_Search := True;
15144 -- Handle entities associated with interface primitives
15146 if Present (Alias_Subp)
15147 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15148 and then not Is_Predefined_Dispatching_Operation (Subp)
15150 -- Search for the primitive in the homonym chain
15153 Find_Primitive_Covering_Interface
15154 (Tagged_Type => Generic_Actual,
15155 Iface_Prim => Alias_Subp);
15157 -- Previous search may not locate primitives covering
15158 -- interfaces defined in generics units or instantiations.
15159 -- (it fails if the covering primitive has formals whose
15160 -- type is also defined in generics or instantiations).
15161 -- In such case we search in the list of primitives of the
15162 -- generic actual for the internal entity that links the
15163 -- interface primitive and the covering primitive.
15166 and then Is_Generic_Type (Parent_Type)
15168 -- This code has been designed to handle only generic
15169 -- formals that implement interfaces that are defined
15170 -- in a generic unit or instantiation. If this code is
15171 -- needed for other cases we must review it because
15172 -- (given that it relies on Original_Location to locate
15173 -- the primitive of Generic_Actual that covers the
15174 -- interface) it could leave linked through attribute
15175 -- Alias entities of unrelated instantiations).
15179 (Scope (Find_Dispatching_Type (Alias_Subp)))
15181 Instantiation_Depth
15182 (Sloc (Find_Dispatching_Type (Alias_Subp))) > 0);
15185 Iface_Prim_Loc : constant Source_Ptr :=
15186 Original_Location (Sloc (Alias_Subp));
15193 First_Elmt (Primitive_Operations (Generic_Actual));
15195 Search : while Present (Elmt) loop
15196 Prim := Node (Elmt);
15198 if Present (Interface_Alias (Prim))
15199 and then Original_Location
15200 (Sloc (Interface_Alias (Prim))) =
15203 Act_Subp := Alias (Prim);
15212 pragma Assert (Present (Act_Subp)
15213 or else Is_Abstract_Type (Generic_Actual)
15214 or else Serious_Errors_Detected > 0);
15216 -- Handle predefined primitives plus the rest of user-defined
15220 Act_Elmt := First_Elmt (Act_List);
15221 while Present (Act_Elmt) loop
15222 Act_Subp := Node (Act_Elmt);
15224 exit when Primitive_Names_Match (Subp, Act_Subp)
15225 and then Type_Conformant
15227 Skip_Controlling_Formals => True)
15228 and then No (Interface_Alias (Act_Subp));
15230 Next_Elmt (Act_Elmt);
15233 if No (Act_Elmt) then
15239 -- Case 1: If the parent is a limited interface then it has the
15240 -- predefined primitives of synchronized interfaces. However, the
15241 -- actual type may be a non-limited type and hence it does not
15242 -- have such primitives.
15244 if Present (Generic_Actual)
15245 and then not Present (Act_Subp)
15246 and then Is_Limited_Interface (Parent_Base)
15247 and then Is_Predefined_Interface_Primitive (Subp)
15251 -- Case 2: Inherit entities associated with interfaces that were
15252 -- not covered by the parent type. We exclude here null interface
15253 -- primitives because they do not need special management.
15255 -- We also exclude interface operations that are renamings. If the
15256 -- subprogram is an explicit renaming of an interface primitive,
15257 -- it is a regular primitive operation, and the presence of its
15258 -- alias is not relevant: it has to be derived like any other
15261 elsif Present (Alias (Subp))
15262 and then Nkind (Unit_Declaration_Node (Subp)) /=
15263 N_Subprogram_Renaming_Declaration
15264 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
15266 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
15267 and then Null_Present (Parent (Alias_Subp)))
15269 -- If this is an abstract private type then we transfer the
15270 -- derivation of the interface primitive from the partial view
15271 -- to the full view. This is safe because all the interfaces
15272 -- must be visible in the partial view. Done to avoid adding
15273 -- a new interface derivation to the private part of the
15274 -- enclosing package; otherwise this new derivation would be
15275 -- decorated as hidden when the analysis of the enclosing
15276 -- package completes.
15278 if Is_Abstract_Type (Derived_Type)
15279 and then In_Private_Part (Current_Scope)
15280 and then Has_Private_Declaration (Derived_Type)
15283 Partial_View : Entity_Id;
15288 Partial_View := First_Entity (Current_Scope);
15290 exit when No (Partial_View)
15291 or else (Has_Private_Declaration (Partial_View)
15293 Full_View (Partial_View) = Derived_Type);
15295 Next_Entity (Partial_View);
15298 -- If the partial view was not found then the source code
15299 -- has errors and the derivation is not needed.
15301 if Present (Partial_View) then
15303 First_Elmt (Primitive_Operations (Partial_View));
15304 while Present (Elmt) loop
15305 Ent := Node (Elmt);
15307 if Present (Alias (Ent))
15308 and then Ultimate_Alias (Ent) = Alias (Subp)
15311 (Ent, Primitive_Operations (Derived_Type));
15318 -- If the interface primitive was not found in the
15319 -- partial view then this interface primitive was
15320 -- overridden. We add a derivation to activate in
15321 -- Derive_Progenitor_Subprograms the machinery to
15325 Derive_Interface_Subprogram
15326 (New_Subp => New_Subp,
15328 Actual_Subp => Act_Subp);
15333 Derive_Interface_Subprogram
15334 (New_Subp => New_Subp,
15336 Actual_Subp => Act_Subp);
15339 -- Case 3: Common derivation
15343 (New_Subp => New_Subp,
15344 Parent_Subp => Subp,
15345 Derived_Type => Derived_Type,
15346 Parent_Type => Parent_Base,
15347 Actual_Subp => Act_Subp);
15350 -- No need to update Act_Elm if we must search for the
15351 -- corresponding operation in the generic actual
15354 and then Present (Act_Elmt)
15356 Next_Elmt (Act_Elmt);
15357 Act_Subp := Node (Act_Elmt);
15364 -- Inherit additional operations from progenitors. If the derived
15365 -- type is a generic actual, there are not new primitive operations
15366 -- for the type because it has those of the actual, and therefore
15367 -- nothing needs to be done. The renamings generated above are not
15368 -- primitive operations, and their purpose is simply to make the
15369 -- proper operations visible within an instantiation.
15371 if No (Generic_Actual) then
15372 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
15376 -- Final check: Direct descendants must have their primitives in the
15377 -- same order. We exclude from this test untagged types and instances
15378 -- of formal derived types. We skip this test if we have already
15379 -- reported serious errors in the sources.
15381 pragma Assert (not Is_Tagged_Type (Derived_Type)
15382 or else Present (Generic_Actual)
15383 or else Serious_Errors_Detected > 0
15384 or else Check_Derived_Type);
15385 end Derive_Subprograms;
15387 --------------------------------
15388 -- Derived_Standard_Character --
15389 --------------------------------
15391 procedure Derived_Standard_Character
15393 Parent_Type : Entity_Id;
15394 Derived_Type : Entity_Id)
15396 Loc : constant Source_Ptr := Sloc (N);
15397 Def : constant Node_Id := Type_Definition (N);
15398 Indic : constant Node_Id := Subtype_Indication (Def);
15399 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
15400 Implicit_Base : constant Entity_Id :=
15402 (E_Enumeration_Type, N, Derived_Type, 'B');
15408 Discard_Node (Process_Subtype (Indic, N));
15410 Set_Etype (Implicit_Base, Parent_Base);
15411 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
15412 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
15414 Set_Is_Character_Type (Implicit_Base, True);
15415 Set_Has_Delayed_Freeze (Implicit_Base);
15417 -- The bounds of the implicit base are the bounds of the parent base.
15418 -- Note that their type is the parent base.
15420 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
15421 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
15423 Set_Scalar_Range (Implicit_Base,
15426 High_Bound => Hi));
15428 Conditional_Delay (Derived_Type, Parent_Type);
15430 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
15431 Set_Etype (Derived_Type, Implicit_Base);
15432 Set_Size_Info (Derived_Type, Parent_Type);
15434 if Unknown_RM_Size (Derived_Type) then
15435 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
15438 Set_Is_Character_Type (Derived_Type, True);
15440 if Nkind (Indic) /= N_Subtype_Indication then
15442 -- If no explicit constraint, the bounds are those
15443 -- of the parent type.
15445 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
15446 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
15447 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
15450 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
15452 -- Because the implicit base is used in the conversion of the bounds, we
15453 -- have to freeze it now. This is similar to what is done for numeric
15454 -- types, and it equally suspicious, but otherwise a non-static bound
15455 -- will have a reference to an unfrozen type, which is rejected by Gigi
15456 -- (???). This requires specific care for definition of stream
15457 -- attributes. For details, see comments at the end of
15458 -- Build_Derived_Numeric_Type.
15460 Freeze_Before (N, Implicit_Base);
15461 end Derived_Standard_Character;
15463 ------------------------------
15464 -- Derived_Type_Declaration --
15465 ------------------------------
15467 procedure Derived_Type_Declaration
15470 Is_Completion : Boolean)
15472 Parent_Type : Entity_Id;
15474 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
15475 -- Check whether the parent type is a generic formal, or derives
15476 -- directly or indirectly from one.
15478 ------------------------
15479 -- Comes_From_Generic --
15480 ------------------------
15482 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
15484 if Is_Generic_Type (Typ) then
15487 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
15490 elsif Is_Private_Type (Typ)
15491 and then Present (Full_View (Typ))
15492 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
15496 elsif Is_Generic_Actual_Type (Typ) then
15502 end Comes_From_Generic;
15506 Def : constant Node_Id := Type_Definition (N);
15507 Iface_Def : Node_Id;
15508 Indic : constant Node_Id := Subtype_Indication (Def);
15509 Extension : constant Node_Id := Record_Extension_Part (Def);
15510 Parent_Node : Node_Id;
15513 -- Start of processing for Derived_Type_Declaration
15516 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
15518 -- Ada 2005 (AI-251): In case of interface derivation check that the
15519 -- parent is also an interface.
15521 if Interface_Present (Def) then
15522 Check_SPARK_05_Restriction ("interface is not allowed", Def);
15524 if not Is_Interface (Parent_Type) then
15525 Diagnose_Interface (Indic, Parent_Type);
15528 Parent_Node := Parent (Base_Type (Parent_Type));
15529 Iface_Def := Type_Definition (Parent_Node);
15531 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
15532 -- other limited interfaces.
15534 if Limited_Present (Def) then
15535 if Limited_Present (Iface_Def) then
15538 elsif Protected_Present (Iface_Def) then
15540 ("descendant of& must be declared"
15541 & " as a protected interface",
15544 elsif Synchronized_Present (Iface_Def) then
15546 ("descendant of& must be declared"
15547 & " as a synchronized interface",
15550 elsif Task_Present (Iface_Def) then
15552 ("descendant of& must be declared as a task interface",
15557 ("(Ada 2005) limited interface cannot "
15558 & "inherit from non-limited interface", Indic);
15561 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
15562 -- from non-limited or limited interfaces.
15564 elsif not Protected_Present (Def)
15565 and then not Synchronized_Present (Def)
15566 and then not Task_Present (Def)
15568 if Limited_Present (Iface_Def) then
15571 elsif Protected_Present (Iface_Def) then
15573 ("descendant of& must be declared"
15574 & " as a protected interface",
15577 elsif Synchronized_Present (Iface_Def) then
15579 ("descendant of& must be declared"
15580 & " as a synchronized interface",
15583 elsif Task_Present (Iface_Def) then
15585 ("descendant of& must be declared as a task interface",
15594 if Is_Tagged_Type (Parent_Type)
15595 and then Is_Concurrent_Type (Parent_Type)
15596 and then not Is_Interface (Parent_Type)
15599 ("parent type of a record extension cannot be "
15600 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
15601 Set_Etype (T, Any_Type);
15605 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
15608 if Is_Tagged_Type (Parent_Type)
15609 and then Is_Non_Empty_List (Interface_List (Def))
15616 Intf := First (Interface_List (Def));
15617 while Present (Intf) loop
15618 T := Find_Type_Of_Subtype_Indic (Intf);
15620 if not Is_Interface (T) then
15621 Diagnose_Interface (Intf, T);
15623 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
15624 -- a limited type from having a nonlimited progenitor.
15626 elsif (Limited_Present (Def)
15627 or else (not Is_Interface (Parent_Type)
15628 and then Is_Limited_Type (Parent_Type)))
15629 and then not Is_Limited_Interface (T)
15632 ("progenitor interface& of limited type must be limited",
15641 if Parent_Type = Any_Type
15642 or else Etype (Parent_Type) = Any_Type
15643 or else (Is_Class_Wide_Type (Parent_Type)
15644 and then Etype (Parent_Type) = T)
15646 -- If Parent_Type is undefined or illegal, make new type into a
15647 -- subtype of Any_Type, and set a few attributes to prevent cascaded
15648 -- errors. If this is a self-definition, emit error now.
15650 if T = Parent_Type or else T = Etype (Parent_Type) then
15651 Error_Msg_N ("type cannot be used in its own definition", Indic);
15654 Set_Ekind (T, Ekind (Parent_Type));
15655 Set_Etype (T, Any_Type);
15656 Set_Scalar_Range (T, Scalar_Range (Any_Type));
15658 if Is_Tagged_Type (T)
15659 and then Is_Record_Type (T)
15661 Set_Direct_Primitive_Operations (T, New_Elmt_List);
15667 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
15668 -- an interface is special because the list of interfaces in the full
15669 -- view can be given in any order. For example:
15671 -- type A is interface;
15672 -- type B is interface and A;
15673 -- type D is new B with private;
15675 -- type D is new A and B with null record; -- 1 --
15677 -- In this case we perform the following transformation of -1-:
15679 -- type D is new B and A with null record;
15681 -- If the parent of the full-view covers the parent of the partial-view
15682 -- we have two possible cases:
15684 -- 1) They have the same parent
15685 -- 2) The parent of the full-view implements some further interfaces
15687 -- In both cases we do not need to perform the transformation. In the
15688 -- first case the source program is correct and the transformation is
15689 -- not needed; in the second case the source program does not fulfill
15690 -- the no-hidden interfaces rule (AI-396) and the error will be reported
15693 -- This transformation not only simplifies the rest of the analysis of
15694 -- this type declaration but also simplifies the correct generation of
15695 -- the object layout to the expander.
15697 if In_Private_Part (Current_Scope)
15698 and then Is_Interface (Parent_Type)
15702 Partial_View : Entity_Id;
15703 Partial_View_Parent : Entity_Id;
15704 New_Iface : Node_Id;
15707 -- Look for the associated private type declaration
15709 Partial_View := First_Entity (Current_Scope);
15711 exit when No (Partial_View)
15712 or else (Has_Private_Declaration (Partial_View)
15713 and then Full_View (Partial_View) = T);
15715 Next_Entity (Partial_View);
15718 -- If the partial view was not found then the source code has
15719 -- errors and the transformation is not needed.
15721 if Present (Partial_View) then
15722 Partial_View_Parent := Etype (Partial_View);
15724 -- If the parent of the full-view covers the parent of the
15725 -- partial-view we have nothing else to do.
15727 if Interface_Present_In_Ancestor
15728 (Parent_Type, Partial_View_Parent)
15732 -- Traverse the list of interfaces of the full-view to look
15733 -- for the parent of the partial-view and perform the tree
15737 Iface := First (Interface_List (Def));
15738 while Present (Iface) loop
15739 if Etype (Iface) = Etype (Partial_View) then
15740 Rewrite (Subtype_Indication (Def),
15741 New_Copy (Subtype_Indication
15742 (Parent (Partial_View))));
15745 Make_Identifier (Sloc (N), Chars (Parent_Type));
15746 Append (New_Iface, Interface_List (Def));
15748 -- Analyze the transformed code
15750 Derived_Type_Declaration (T, N, Is_Completion);
15761 -- Only composite types other than array types are allowed to have
15764 if Present (Discriminant_Specifications (N)) then
15765 if (Is_Elementary_Type (Parent_Type)
15767 Is_Array_Type (Parent_Type))
15768 and then not Error_Posted (N)
15771 ("elementary or array type cannot have discriminants",
15772 Defining_Identifier (First (Discriminant_Specifications (N))));
15773 Set_Has_Discriminants (T, False);
15775 -- The type is allowed to have discriminants
15778 Check_SPARK_05_Restriction ("discriminant type is not allowed", N);
15782 -- In Ada 83, a derived type defined in a package specification cannot
15783 -- be used for further derivation until the end of its visible part.
15784 -- Note that derivation in the private part of the package is allowed.
15786 if Ada_Version = Ada_83
15787 and then Is_Derived_Type (Parent_Type)
15788 and then In_Visible_Part (Scope (Parent_Type))
15790 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
15792 ("(Ada 83): premature use of type for derivation", Indic);
15796 -- Check for early use of incomplete or private type
15798 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
15799 Error_Msg_N ("premature derivation of incomplete type", Indic);
15802 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
15803 and then not Comes_From_Generic (Parent_Type))
15804 or else Has_Private_Component (Parent_Type)
15806 -- The ancestor type of a formal type can be incomplete, in which
15807 -- case only the operations of the partial view are available in the
15808 -- generic. Subsequent checks may be required when the full view is
15809 -- analyzed to verify that a derivation from a tagged type has an
15812 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
15815 elsif No (Underlying_Type (Parent_Type))
15816 or else Has_Private_Component (Parent_Type)
15819 ("premature derivation of derived or private type", Indic);
15821 -- Flag the type itself as being in error, this prevents some
15822 -- nasty problems with subsequent uses of the malformed type.
15824 Set_Error_Posted (T);
15826 -- Check that within the immediate scope of an untagged partial
15827 -- view it's illegal to derive from the partial view if the
15828 -- full view is tagged. (7.3(7))
15830 -- We verify that the Parent_Type is a partial view by checking
15831 -- that it is not a Full_Type_Declaration (i.e. a private type or
15832 -- private extension declaration), to distinguish a partial view
15833 -- from a derivation from a private type which also appears as
15834 -- E_Private_Type. If the parent base type is not declared in an
15835 -- enclosing scope there is no need to check.
15837 elsif Present (Full_View (Parent_Type))
15838 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
15839 and then not Is_Tagged_Type (Parent_Type)
15840 and then Is_Tagged_Type (Full_View (Parent_Type))
15841 and then In_Open_Scopes (Scope (Base_Type (Parent_Type)))
15844 ("premature derivation from type with tagged full view",
15849 -- Check that form of derivation is appropriate
15851 Taggd := Is_Tagged_Type (Parent_Type);
15853 -- Perhaps the parent type should be changed to the class-wide type's
15854 -- specific type in this case to prevent cascading errors ???
15856 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
15857 Error_Msg_N ("parent type must not be a class-wide type", Indic);
15861 if Present (Extension) and then not Taggd then
15863 ("type derived from untagged type cannot have extension", Indic);
15865 elsif No (Extension) and then Taggd then
15867 -- If this declaration is within a private part (or body) of a
15868 -- generic instantiation then the derivation is allowed (the parent
15869 -- type can only appear tagged in this case if it's a generic actual
15870 -- type, since it would otherwise have been rejected in the analysis
15871 -- of the generic template).
15873 if not Is_Generic_Actual_Type (Parent_Type)
15874 or else In_Visible_Part (Scope (Parent_Type))
15876 if Is_Class_Wide_Type (Parent_Type) then
15878 ("parent type must not be a class-wide type", Indic);
15880 -- Use specific type to prevent cascaded errors.
15882 Parent_Type := Etype (Parent_Type);
15886 ("type derived from tagged type must have extension", Indic);
15891 -- AI-443: Synchronized formal derived types require a private
15892 -- extension. There is no point in checking the ancestor type or
15893 -- the progenitors since the construct is wrong to begin with.
15895 if Ada_Version >= Ada_2005
15896 and then Is_Generic_Type (T)
15897 and then Present (Original_Node (N))
15900 Decl : constant Node_Id := Original_Node (N);
15903 if Nkind (Decl) = N_Formal_Type_Declaration
15904 and then Nkind (Formal_Type_Definition (Decl)) =
15905 N_Formal_Derived_Type_Definition
15906 and then Synchronized_Present (Formal_Type_Definition (Decl))
15907 and then No (Extension)
15909 -- Avoid emitting a duplicate error message
15911 and then not Error_Posted (Indic)
15914 ("synchronized derived type must have extension", N);
15919 if Null_Exclusion_Present (Def)
15920 and then not Is_Access_Type (Parent_Type)
15922 Error_Msg_N ("null exclusion can only apply to an access type", N);
15925 -- Avoid deriving parent primitives of underlying record views
15927 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
15928 Derive_Subps => not Is_Underlying_Record_View (T));
15930 -- AI-419: The parent type of an explicitly limited derived type must
15931 -- be a limited type or a limited interface.
15933 if Limited_Present (Def) then
15934 Set_Is_Limited_Record (T);
15936 if Is_Interface (T) then
15937 Set_Is_Limited_Interface (T);
15940 if not Is_Limited_Type (Parent_Type)
15942 (not Is_Interface (Parent_Type)
15943 or else not Is_Limited_Interface (Parent_Type))
15945 -- AI05-0096: a derivation in the private part of an instance is
15946 -- legal if the generic formal is untagged limited, and the actual
15949 if Is_Generic_Actual_Type (Parent_Type)
15950 and then In_Private_Part (Current_Scope)
15953 (Generic_Parent_Type (Parent (Parent_Type)))
15959 ("parent type& of limited type must be limited",
15965 -- In SPARK, there are no derived type definitions other than type
15966 -- extensions of tagged record types.
15968 if No (Extension) then
15969 Check_SPARK_05_Restriction
15970 ("derived type is not allowed", Original_Node (N));
15972 end Derived_Type_Declaration;
15974 ------------------------
15975 -- Diagnose_Interface --
15976 ------------------------
15978 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
15980 if not Is_Interface (E)
15981 and then E /= Any_Type
15983 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
15985 end Diagnose_Interface;
15987 ----------------------------------
15988 -- Enumeration_Type_Declaration --
15989 ----------------------------------
15991 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
15998 -- Create identifier node representing lower bound
16000 B_Node := New_Node (N_Identifier, Sloc (Def));
16001 L := First (Literals (Def));
16002 Set_Chars (B_Node, Chars (L));
16003 Set_Entity (B_Node, L);
16004 Set_Etype (B_Node, T);
16005 Set_Is_Static_Expression (B_Node, True);
16007 R_Node := New_Node (N_Range, Sloc (Def));
16008 Set_Low_Bound (R_Node, B_Node);
16010 Set_Ekind (T, E_Enumeration_Type);
16011 Set_First_Literal (T, L);
16013 Set_Is_Constrained (T);
16017 -- Loop through literals of enumeration type setting pos and rep values
16018 -- except that if the Ekind is already set, then it means the literal
16019 -- was already constructed (case of a derived type declaration and we
16020 -- should not disturb the Pos and Rep values.
16022 while Present (L) loop
16023 if Ekind (L) /= E_Enumeration_Literal then
16024 Set_Ekind (L, E_Enumeration_Literal);
16025 Set_Enumeration_Pos (L, Ev);
16026 Set_Enumeration_Rep (L, Ev);
16027 Set_Is_Known_Valid (L, True);
16031 New_Overloaded_Entity (L);
16032 Generate_Definition (L);
16033 Set_Convention (L, Convention_Intrinsic);
16035 -- Case of character literal
16037 if Nkind (L) = N_Defining_Character_Literal then
16038 Set_Is_Character_Type (T, True);
16040 -- Check violation of No_Wide_Characters
16042 if Restriction_Check_Required (No_Wide_Characters) then
16043 Get_Name_String (Chars (L));
16045 if Name_Len >= 3 and then Name_Buffer (1 .. 2) = "QW" then
16046 Check_Restriction (No_Wide_Characters, L);
16055 -- Now create a node representing upper bound
16057 B_Node := New_Node (N_Identifier, Sloc (Def));
16058 Set_Chars (B_Node, Chars (Last (Literals (Def))));
16059 Set_Entity (B_Node, Last (Literals (Def)));
16060 Set_Etype (B_Node, T);
16061 Set_Is_Static_Expression (B_Node, True);
16063 Set_High_Bound (R_Node, B_Node);
16065 -- Initialize various fields of the type. Some of this information
16066 -- may be overwritten later through rep.clauses.
16068 Set_Scalar_Range (T, R_Node);
16069 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
16070 Set_Enum_Esize (T);
16071 Set_Enum_Pos_To_Rep (T, Empty);
16073 -- Set Discard_Names if configuration pragma set, or if there is
16074 -- a parameterless pragma in the current declarative region
16076 if Global_Discard_Names or else Discard_Names (Scope (T)) then
16077 Set_Discard_Names (T);
16080 -- Process end label if there is one
16082 if Present (Def) then
16083 Process_End_Label (Def, 'e', T);
16085 end Enumeration_Type_Declaration;
16087 ---------------------------------
16088 -- Expand_To_Stored_Constraint --
16089 ---------------------------------
16091 function Expand_To_Stored_Constraint
16093 Constraint : Elist_Id) return Elist_Id
16095 Explicitly_Discriminated_Type : Entity_Id;
16096 Expansion : Elist_Id;
16097 Discriminant : Entity_Id;
16099 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
16100 -- Find the nearest type that actually specifies discriminants
16102 ---------------------------------
16103 -- Type_With_Explicit_Discrims --
16104 ---------------------------------
16106 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
16107 Typ : constant E := Base_Type (Id);
16110 if Ekind (Typ) in Incomplete_Or_Private_Kind then
16111 if Present (Full_View (Typ)) then
16112 return Type_With_Explicit_Discrims (Full_View (Typ));
16116 if Has_Discriminants (Typ) then
16121 if Etype (Typ) = Typ then
16123 elsif Has_Discriminants (Typ) then
16126 return Type_With_Explicit_Discrims (Etype (Typ));
16129 end Type_With_Explicit_Discrims;
16131 -- Start of processing for Expand_To_Stored_Constraint
16134 if No (Constraint) or else Is_Empty_Elmt_List (Constraint) then
16138 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
16140 if No (Explicitly_Discriminated_Type) then
16144 Expansion := New_Elmt_List;
16147 First_Stored_Discriminant (Explicitly_Discriminated_Type);
16148 while Present (Discriminant) loop
16150 (Get_Discriminant_Value
16151 (Discriminant, Explicitly_Discriminated_Type, Constraint),
16153 Next_Stored_Discriminant (Discriminant);
16157 end Expand_To_Stored_Constraint;
16159 ---------------------------
16160 -- Find_Hidden_Interface --
16161 ---------------------------
16163 function Find_Hidden_Interface
16165 Dest : Elist_Id) return Entity_Id
16168 Iface_Elmt : Elmt_Id;
16171 if Present (Src) and then Present (Dest) then
16172 Iface_Elmt := First_Elmt (Src);
16173 while Present (Iface_Elmt) loop
16174 Iface := Node (Iface_Elmt);
16176 if Is_Interface (Iface)
16177 and then not Contain_Interface (Iface, Dest)
16182 Next_Elmt (Iface_Elmt);
16187 end Find_Hidden_Interface;
16189 --------------------
16190 -- Find_Type_Name --
16191 --------------------
16193 function Find_Type_Name (N : Node_Id) return Entity_Id is
16194 Id : constant Entity_Id := Defining_Identifier (N);
16196 New_Id : Entity_Id;
16197 Prev_Par : Node_Id;
16199 procedure Check_Duplicate_Aspects;
16200 -- Check that aspects specified in a completion have not been specified
16201 -- already in the partial view. Type_Invariant and others can be
16202 -- specified on either view but never on both.
16204 procedure Tag_Mismatch;
16205 -- Diagnose a tagged partial view whose full view is untagged.
16206 -- We post the message on the full view, with a reference to
16207 -- the previous partial view. The partial view can be private
16208 -- or incomplete, and these are handled in a different manner,
16209 -- so we determine the position of the error message from the
16210 -- respective slocs of both.
16212 -----------------------------
16213 -- Check_Duplicate_Aspects --
16214 -----------------------------
16215 procedure Check_Duplicate_Aspects is
16216 Prev_Aspects : constant List_Id := Aspect_Specifications (Prev_Par);
16217 Full_Aspects : constant List_Id := Aspect_Specifications (N);
16218 F_Spec, P_Spec : Node_Id;
16221 if Present (Prev_Aspects) and then Present (Full_Aspects) then
16222 F_Spec := First (Full_Aspects);
16223 while Present (F_Spec) loop
16224 P_Spec := First (Prev_Aspects);
16225 while Present (P_Spec) loop
16227 Chars (Identifier (P_Spec)) = Chars (Identifier (F_Spec))
16230 ("aspect already specified in private declaration",
16242 end Check_Duplicate_Aspects;
16248 procedure Tag_Mismatch is
16250 if Sloc (Prev) < Sloc (Id) then
16251 if Ada_Version >= Ada_2012
16252 and then Nkind (N) = N_Private_Type_Declaration
16255 ("declaration of private } must be a tagged type ", Id, Prev);
16258 ("full declaration of } must be a tagged type ", Id, Prev);
16262 if Ada_Version >= Ada_2012
16263 and then Nkind (N) = N_Private_Type_Declaration
16266 ("declaration of private } must be a tagged type ", Prev, Id);
16269 ("full declaration of } must be a tagged type ", Prev, Id);
16274 -- Start of processing for Find_Type_Name
16277 -- Find incomplete declaration, if one was given
16279 Prev := Current_Entity_In_Scope (Id);
16281 -- New type declaration
16287 -- Previous declaration exists
16290 Prev_Par := Parent (Prev);
16292 -- Error if not incomplete/private case except if previous
16293 -- declaration is implicit, etc. Enter_Name will emit error if
16296 if not Is_Incomplete_Or_Private_Type (Prev) then
16300 -- Check invalid completion of private or incomplete type
16302 elsif not Nkind_In (N, N_Full_Type_Declaration,
16303 N_Task_Type_Declaration,
16304 N_Protected_Type_Declaration)
16306 (Ada_Version < Ada_2012
16307 or else not Is_Incomplete_Type (Prev)
16308 or else not Nkind_In (N, N_Private_Type_Declaration,
16309 N_Private_Extension_Declaration))
16311 -- Completion must be a full type declarations (RM 7.3(4))
16313 Error_Msg_Sloc := Sloc (Prev);
16314 Error_Msg_NE ("invalid completion of }", Id, Prev);
16316 -- Set scope of Id to avoid cascaded errors. Entity is never
16317 -- examined again, except when saving globals in generics.
16319 Set_Scope (Id, Current_Scope);
16322 -- If this is a repeated incomplete declaration, no further
16323 -- checks are possible.
16325 if Nkind (N) = N_Incomplete_Type_Declaration then
16329 -- Case of full declaration of incomplete type
16331 elsif Ekind (Prev) = E_Incomplete_Type
16332 and then (Ada_Version < Ada_2012
16333 or else No (Full_View (Prev))
16334 or else not Is_Private_Type (Full_View (Prev)))
16336 -- Indicate that the incomplete declaration has a matching full
16337 -- declaration. The defining occurrence of the incomplete
16338 -- declaration remains the visible one, and the procedure
16339 -- Get_Full_View dereferences it whenever the type is used.
16341 if Present (Full_View (Prev)) then
16342 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16345 Set_Full_View (Prev, Id);
16346 Append_Entity (Id, Current_Scope);
16347 Set_Is_Public (Id, Is_Public (Prev));
16348 Set_Is_Internal (Id);
16351 -- If the incomplete view is tagged, a class_wide type has been
16352 -- created already. Use it for the private type as well, in order
16353 -- to prevent multiple incompatible class-wide types that may be
16354 -- created for self-referential anonymous access components.
16356 if Is_Tagged_Type (Prev)
16357 and then Present (Class_Wide_Type (Prev))
16359 Set_Ekind (Id, Ekind (Prev)); -- will be reset later
16360 Set_Class_Wide_Type (Id, Class_Wide_Type (Prev));
16362 -- If the incomplete type is completed by a private declaration
16363 -- the class-wide type remains associated with the incomplete
16364 -- type, to prevent order-of-elaboration issues in gigi, else
16365 -- we associate the class-wide type with the known full view.
16367 if Nkind (N) /= N_Private_Type_Declaration then
16368 Set_Etype (Class_Wide_Type (Id), Id);
16372 -- Case of full declaration of private type
16375 -- If the private type was a completion of an incomplete type then
16376 -- update Prev to reference the private type
16378 if Ada_Version >= Ada_2012
16379 and then Ekind (Prev) = E_Incomplete_Type
16380 and then Present (Full_View (Prev))
16381 and then Is_Private_Type (Full_View (Prev))
16383 Prev := Full_View (Prev);
16384 Prev_Par := Parent (Prev);
16387 if Nkind (N) = N_Full_Type_Declaration
16389 (Type_Definition (N), N_Record_Definition,
16390 N_Derived_Type_Definition)
16391 and then Interface_Present (Type_Definition (N))
16394 ("completion of private type cannot be an interface", N);
16397 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
16398 if Etype (Prev) /= Prev then
16400 -- Prev is a private subtype or a derived type, and needs
16403 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
16406 elsif Ekind (Prev) = E_Private_Type
16407 and then Nkind_In (N, N_Task_Type_Declaration,
16408 N_Protected_Type_Declaration)
16411 ("completion of nonlimited type cannot be limited", N);
16413 elsif Ekind (Prev) = E_Record_Type_With_Private
16414 and then Nkind_In (N, N_Task_Type_Declaration,
16415 N_Protected_Type_Declaration)
16417 if not Is_Limited_Record (Prev) then
16419 ("completion of nonlimited type cannot be limited", N);
16421 elsif No (Interface_List (N)) then
16423 ("completion of tagged private type must be tagged",
16428 -- Ada 2005 (AI-251): Private extension declaration of a task
16429 -- type or a protected type. This case arises when covering
16430 -- interface types.
16432 elsif Nkind_In (N, N_Task_Type_Declaration,
16433 N_Protected_Type_Declaration)
16437 elsif Nkind (N) /= N_Full_Type_Declaration
16438 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
16441 ("full view of private extension must be an extension", N);
16443 elsif not (Abstract_Present (Parent (Prev)))
16444 and then Abstract_Present (Type_Definition (N))
16447 ("full view of non-abstract extension cannot be abstract", N);
16450 if not In_Private_Part (Current_Scope) then
16452 ("declaration of full view must appear in private part", N);
16455 if Ada_Version >= Ada_2012 then
16456 Check_Duplicate_Aspects;
16459 Copy_And_Swap (Prev, Id);
16460 Set_Has_Private_Declaration (Prev);
16461 Set_Has_Private_Declaration (Id);
16463 -- Preserve aspect and iterator flags that may have been set on
16464 -- the partial view.
16466 Set_Has_Delayed_Aspects (Prev, Has_Delayed_Aspects (Id));
16467 Set_Has_Implicit_Dereference (Prev, Has_Implicit_Dereference (Id));
16469 -- If no error, propagate freeze_node from private to full view.
16470 -- It may have been generated for an early operational item.
16472 if Present (Freeze_Node (Id))
16473 and then Serious_Errors_Detected = 0
16474 and then No (Full_View (Id))
16476 Set_Freeze_Node (Prev, Freeze_Node (Id));
16477 Set_Freeze_Node (Id, Empty);
16478 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
16481 Set_Full_View (Id, Prev);
16485 -- Verify that full declaration conforms to partial one
16487 if Is_Incomplete_Or_Private_Type (Prev)
16488 and then Present (Discriminant_Specifications (Prev_Par))
16490 if Present (Discriminant_Specifications (N)) then
16491 if Ekind (Prev) = E_Incomplete_Type then
16492 Check_Discriminant_Conformance (N, Prev, Prev);
16494 Check_Discriminant_Conformance (N, Prev, Id);
16499 ("missing discriminants in full type declaration", N);
16501 -- To avoid cascaded errors on subsequent use, share the
16502 -- discriminants of the partial view.
16504 Set_Discriminant_Specifications (N,
16505 Discriminant_Specifications (Prev_Par));
16509 -- A prior untagged partial view can have an associated class-wide
16510 -- type due to use of the class attribute, and in this case the full
16511 -- type must also be tagged. This Ada 95 usage is deprecated in favor
16512 -- of incomplete tagged declarations, but we check for it.
16515 and then (Is_Tagged_Type (Prev)
16516 or else Present (Class_Wide_Type (Prev)))
16518 -- Ada 2012 (AI05-0162): A private type may be the completion of
16519 -- an incomplete type.
16521 if Ada_Version >= Ada_2012
16522 and then Is_Incomplete_Type (Prev)
16523 and then Nkind_In (N, N_Private_Type_Declaration,
16524 N_Private_Extension_Declaration)
16526 -- No need to check private extensions since they are tagged
16528 if Nkind (N) = N_Private_Type_Declaration
16529 and then not Tagged_Present (N)
16534 -- The full declaration is either a tagged type (including
16535 -- a synchronized type that implements interfaces) or a
16536 -- type extension, otherwise this is an error.
16538 elsif Nkind_In (N, N_Task_Type_Declaration,
16539 N_Protected_Type_Declaration)
16541 if No (Interface_List (N))
16542 and then not Error_Posted (N)
16547 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
16549 -- Indicate that the previous declaration (tagged incomplete
16550 -- or private declaration) requires the same on the full one.
16552 if not Tagged_Present (Type_Definition (N)) then
16554 Set_Is_Tagged_Type (Id);
16557 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
16558 if No (Record_Extension_Part (Type_Definition (N))) then
16560 ("full declaration of } must be a record extension",
16563 -- Set some attributes to produce a usable full view
16565 Set_Is_Tagged_Type (Id);
16574 and then Nkind (Parent (Prev)) = N_Incomplete_Type_Declaration
16575 and then Present (Premature_Use (Parent (Prev)))
16577 Error_Msg_Sloc := Sloc (N);
16579 ("\full declaration #", Premature_Use (Parent (Prev)));
16584 end Find_Type_Name;
16586 -------------------------
16587 -- Find_Type_Of_Object --
16588 -------------------------
16590 function Find_Type_Of_Object
16591 (Obj_Def : Node_Id;
16592 Related_Nod : Node_Id) return Entity_Id
16594 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
16595 P : Node_Id := Parent (Obj_Def);
16600 -- If the parent is a component_definition node we climb to the
16601 -- component_declaration node
16603 if Nkind (P) = N_Component_Definition then
16607 -- Case of an anonymous array subtype
16609 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
16610 N_Unconstrained_Array_Definition)
16613 Array_Type_Declaration (T, Obj_Def);
16615 -- Create an explicit subtype whenever possible
16617 elsif Nkind (P) /= N_Component_Declaration
16618 and then Def_Kind = N_Subtype_Indication
16620 -- Base name of subtype on object name, which will be unique in
16621 -- the current scope.
16623 -- If this is a duplicate declaration, return base type, to avoid
16624 -- generating duplicate anonymous types.
16626 if Error_Posted (P) then
16627 Analyze (Subtype_Mark (Obj_Def));
16628 return Entity (Subtype_Mark (Obj_Def));
16633 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
16635 T := Make_Defining_Identifier (Sloc (P), Nam);
16637 Insert_Action (Obj_Def,
16638 Make_Subtype_Declaration (Sloc (P),
16639 Defining_Identifier => T,
16640 Subtype_Indication => Relocate_Node (Obj_Def)));
16642 -- This subtype may need freezing, and this will not be done
16643 -- automatically if the object declaration is not in declarative
16644 -- part. Since this is an object declaration, the type cannot always
16645 -- be frozen here. Deferred constants do not freeze their type
16646 -- (which often enough will be private).
16648 if Nkind (P) = N_Object_Declaration
16649 and then Constant_Present (P)
16650 and then No (Expression (P))
16654 -- Here we freeze the base type of object type to catch premature use
16655 -- of discriminated private type without a full view.
16658 Insert_Actions (Obj_Def, Freeze_Entity (Base_Type (T), P));
16661 -- Ada 2005 AI-406: the object definition in an object declaration
16662 -- can be an access definition.
16664 elsif Def_Kind = N_Access_Definition then
16665 T := Access_Definition (Related_Nod, Obj_Def);
16667 Set_Is_Local_Anonymous_Access
16669 V => (Ada_Version < Ada_2012)
16670 or else (Nkind (P) /= N_Object_Declaration)
16671 or else Is_Library_Level_Entity (Defining_Identifier (P)));
16673 -- Otherwise, the object definition is just a subtype_mark
16676 T := Process_Subtype (Obj_Def, Related_Nod);
16678 -- If expansion is disabled an object definition that is an aggregate
16679 -- will not get expanded and may lead to scoping problems in the back
16680 -- end, if the object is referenced in an inner scope. In that case
16681 -- create an itype reference for the object definition now. This
16682 -- may be redundant in some cases, but harmless.
16685 and then Nkind (Related_Nod) = N_Object_Declaration
16688 Build_Itype_Reference (T, Related_Nod);
16693 end Find_Type_Of_Object;
16695 --------------------------------
16696 -- Find_Type_Of_Subtype_Indic --
16697 --------------------------------
16699 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
16703 -- Case of subtype mark with a constraint
16705 if Nkind (S) = N_Subtype_Indication then
16706 Find_Type (Subtype_Mark (S));
16707 Typ := Entity (Subtype_Mark (S));
16710 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
16713 ("incorrect constraint for this kind of type", Constraint (S));
16714 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
16717 -- Otherwise we have a subtype mark without a constraint
16719 elsif Error_Posted (S) then
16720 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
16728 -- Check No_Wide_Characters restriction
16730 Check_Wide_Character_Restriction (Typ, S);
16733 end Find_Type_Of_Subtype_Indic;
16735 -------------------------------------
16736 -- Floating_Point_Type_Declaration --
16737 -------------------------------------
16739 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
16740 Digs : constant Node_Id := Digits_Expression (Def);
16741 Max_Digs_Val : constant Uint := Digits_Value (Standard_Long_Long_Float);
16743 Base_Typ : Entity_Id;
16744 Implicit_Base : Entity_Id;
16747 function Can_Derive_From (E : Entity_Id) return Boolean;
16748 -- Find if given digits value, and possibly a specified range, allows
16749 -- derivation from specified type
16751 function Find_Base_Type return Entity_Id;
16752 -- Find a predefined base type that Def can derive from, or generate
16753 -- an error and substitute Long_Long_Float if none exists.
16755 ---------------------
16756 -- Can_Derive_From --
16757 ---------------------
16759 function Can_Derive_From (E : Entity_Id) return Boolean is
16760 Spec : constant Entity_Id := Real_Range_Specification (Def);
16763 -- Check specified "digits" constraint
16765 if Digs_Val > Digits_Value (E) then
16769 -- Check for matching range, if specified
16771 if Present (Spec) then
16772 if Expr_Value_R (Type_Low_Bound (E)) >
16773 Expr_Value_R (Low_Bound (Spec))
16778 if Expr_Value_R (Type_High_Bound (E)) <
16779 Expr_Value_R (High_Bound (Spec))
16786 end Can_Derive_From;
16788 --------------------
16789 -- Find_Base_Type --
16790 --------------------
16792 function Find_Base_Type return Entity_Id is
16793 Choice : Elmt_Id := First_Elmt (Predefined_Float_Types);
16796 -- Iterate over the predefined types in order, returning the first
16797 -- one that Def can derive from.
16799 while Present (Choice) loop
16800 if Can_Derive_From (Node (Choice)) then
16801 return Node (Choice);
16804 Next_Elmt (Choice);
16807 -- If we can't derive from any existing type, use Long_Long_Float
16808 -- and give appropriate message explaining the problem.
16810 if Digs_Val > Max_Digs_Val then
16811 -- It might be the case that there is a type with the requested
16812 -- range, just not the combination of digits and range.
16815 ("no predefined type has requested range and precision",
16816 Real_Range_Specification (Def));
16820 ("range too large for any predefined type",
16821 Real_Range_Specification (Def));
16824 return Standard_Long_Long_Float;
16825 end Find_Base_Type;
16827 -- Start of processing for Floating_Point_Type_Declaration
16830 Check_Restriction (No_Floating_Point, Def);
16832 -- Create an implicit base type
16835 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
16837 -- Analyze and verify digits value
16839 Analyze_And_Resolve (Digs, Any_Integer);
16840 Check_Digits_Expression (Digs);
16841 Digs_Val := Expr_Value (Digs);
16843 -- Process possible range spec and find correct type to derive from
16845 Process_Real_Range_Specification (Def);
16847 -- Check that requested number of digits is not too high.
16849 if Digs_Val > Max_Digs_Val then
16850 -- The check for Max_Base_Digits may be somewhat expensive, as it
16851 -- requires reading System, so only do it when necessary.
16854 Max_Base_Digits : constant Uint :=
16857 (Parent (RTE (RE_Max_Base_Digits))));
16860 if Digs_Val > Max_Base_Digits then
16861 Error_Msg_Uint_1 := Max_Base_Digits;
16862 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
16864 elsif No (Real_Range_Specification (Def)) then
16865 Error_Msg_Uint_1 := Max_Digs_Val;
16866 Error_Msg_N ("types with more than ^ digits need range spec "
16867 & "(RM 3.5.7(6))", Digs);
16872 -- Find a suitable type to derive from or complain and use a substitute
16874 Base_Typ := Find_Base_Type;
16876 -- If there are bounds given in the declaration use them as the bounds
16877 -- of the type, otherwise use the bounds of the predefined base type
16878 -- that was chosen based on the Digits value.
16880 if Present (Real_Range_Specification (Def)) then
16881 Set_Scalar_Range (T, Real_Range_Specification (Def));
16882 Set_Is_Constrained (T);
16884 -- The bounds of this range must be converted to machine numbers
16885 -- in accordance with RM 4.9(38).
16887 Bound := Type_Low_Bound (T);
16889 if Nkind (Bound) = N_Real_Literal then
16891 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
16892 Set_Is_Machine_Number (Bound);
16895 Bound := Type_High_Bound (T);
16897 if Nkind (Bound) = N_Real_Literal then
16899 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
16900 Set_Is_Machine_Number (Bound);
16904 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
16907 -- Complete definition of implicit base and declared first subtype. The
16908 -- inheritance of the rep item chain ensures that SPARK-related pragmas
16909 -- are not clobbered when the floating point type acts as a full view of
16912 Set_Etype (Implicit_Base, Base_Typ);
16913 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
16914 Set_Size_Info (Implicit_Base, Base_Typ);
16915 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
16916 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
16917 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
16918 Set_Float_Rep (Implicit_Base, Float_Rep (Base_Typ));
16920 Set_Ekind (T, E_Floating_Point_Subtype);
16921 Set_Etype (T, Implicit_Base);
16922 Set_Size_Info (T, Implicit_Base);
16923 Set_RM_Size (T, RM_Size (Implicit_Base));
16924 Inherit_Rep_Item_Chain (T, Implicit_Base);
16925 Set_Digits_Value (T, Digs_Val);
16926 end Floating_Point_Type_Declaration;
16928 ----------------------------
16929 -- Get_Discriminant_Value --
16930 ----------------------------
16932 -- This is the situation:
16934 -- There is a non-derived type
16936 -- type T0 (Dx, Dy, Dz...)
16938 -- There are zero or more levels of derivation, with each derivation
16939 -- either purely inheriting the discriminants, or defining its own.
16941 -- type Ti is new Ti-1
16943 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
16945 -- subtype Ti is ...
16947 -- The subtype issue is avoided by the use of Original_Record_Component,
16948 -- and the fact that derived subtypes also derive the constraints.
16950 -- This chain leads back from
16952 -- Typ_For_Constraint
16954 -- Typ_For_Constraint has discriminants, and the value for each
16955 -- discriminant is given by its corresponding Elmt of Constraints.
16957 -- Discriminant is some discriminant in this hierarchy
16959 -- We need to return its value
16961 -- We do this by recursively searching each level, and looking for
16962 -- Discriminant. Once we get to the bottom, we start backing up
16963 -- returning the value for it which may in turn be a discriminant
16964 -- further up, so on the backup we continue the substitution.
16966 function Get_Discriminant_Value
16967 (Discriminant : Entity_Id;
16968 Typ_For_Constraint : Entity_Id;
16969 Constraint : Elist_Id) return Node_Id
16971 function Root_Corresponding_Discriminant
16972 (Discr : Entity_Id) return Entity_Id;
16973 -- Given a discriminant, traverse the chain of inherited discriminants
16974 -- and return the topmost discriminant.
16976 function Search_Derivation_Levels
16978 Discrim_Values : Elist_Id;
16979 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
16980 -- This is the routine that performs the recursive search of levels
16981 -- as described above.
16983 -------------------------------------
16984 -- Root_Corresponding_Discriminant --
16985 -------------------------------------
16987 function Root_Corresponding_Discriminant
16988 (Discr : Entity_Id) return Entity_Id
16994 while Present (Corresponding_Discriminant (D)) loop
16995 D := Corresponding_Discriminant (D);
16999 end Root_Corresponding_Discriminant;
17001 ------------------------------
17002 -- Search_Derivation_Levels --
17003 ------------------------------
17005 function Search_Derivation_Levels
17007 Discrim_Values : Elist_Id;
17008 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
17012 Result : Node_Or_Entity_Id;
17013 Result_Entity : Node_Id;
17016 -- If inappropriate type, return Error, this happens only in
17017 -- cascaded error situations, and we want to avoid a blow up.
17019 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
17023 -- Look deeper if possible. Use Stored_Constraints only for
17024 -- untagged types. For tagged types use the given constraint.
17025 -- This asymmetry needs explanation???
17027 if not Stored_Discrim_Values
17028 and then Present (Stored_Constraint (Ti))
17029 and then not Is_Tagged_Type (Ti)
17032 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
17035 Td : constant Entity_Id := Etype (Ti);
17039 Result := Discriminant;
17042 if Present (Stored_Constraint (Ti)) then
17044 Search_Derivation_Levels
17045 (Td, Stored_Constraint (Ti), True);
17048 Search_Derivation_Levels
17049 (Td, Discrim_Values, Stored_Discrim_Values);
17055 -- Extra underlying places to search, if not found above. For
17056 -- concurrent types, the relevant discriminant appears in the
17057 -- corresponding record. For a type derived from a private type
17058 -- without discriminant, the full view inherits the discriminants
17059 -- of the full view of the parent.
17061 if Result = Discriminant then
17062 if Is_Concurrent_Type (Ti)
17063 and then Present (Corresponding_Record_Type (Ti))
17066 Search_Derivation_Levels (
17067 Corresponding_Record_Type (Ti),
17069 Stored_Discrim_Values);
17071 elsif Is_Private_Type (Ti)
17072 and then not Has_Discriminants (Ti)
17073 and then Present (Full_View (Ti))
17074 and then Etype (Full_View (Ti)) /= Ti
17077 Search_Derivation_Levels (
17080 Stored_Discrim_Values);
17084 -- If Result is not a (reference to a) discriminant, return it,
17085 -- otherwise set Result_Entity to the discriminant.
17087 if Nkind (Result) = N_Defining_Identifier then
17088 pragma Assert (Result = Discriminant);
17089 Result_Entity := Result;
17092 if not Denotes_Discriminant (Result) then
17096 Result_Entity := Entity (Result);
17099 -- See if this level of derivation actually has discriminants
17100 -- because tagged derivations can add them, hence the lower
17101 -- levels need not have any.
17103 if not Has_Discriminants (Ti) then
17107 -- Scan Ti's discriminants for Result_Entity,
17108 -- and return its corresponding value, if any.
17110 Result_Entity := Original_Record_Component (Result_Entity);
17112 Assoc := First_Elmt (Discrim_Values);
17114 if Stored_Discrim_Values then
17115 Disc := First_Stored_Discriminant (Ti);
17117 Disc := First_Discriminant (Ti);
17120 while Present (Disc) loop
17121 pragma Assert (Present (Assoc));
17123 if Original_Record_Component (Disc) = Result_Entity then
17124 return Node (Assoc);
17129 if Stored_Discrim_Values then
17130 Next_Stored_Discriminant (Disc);
17132 Next_Discriminant (Disc);
17136 -- Could not find it
17139 end Search_Derivation_Levels;
17143 Result : Node_Or_Entity_Id;
17145 -- Start of processing for Get_Discriminant_Value
17148 -- ??? This routine is a gigantic mess and will be deleted. For the
17149 -- time being just test for the trivial case before calling recurse.
17151 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
17157 D := First_Discriminant (Typ_For_Constraint);
17158 E := First_Elmt (Constraint);
17159 while Present (D) loop
17160 if Chars (D) = Chars (Discriminant) then
17164 Next_Discriminant (D);
17170 Result := Search_Derivation_Levels
17171 (Typ_For_Constraint, Constraint, False);
17173 -- ??? hack to disappear when this routine is gone
17175 if Nkind (Result) = N_Defining_Identifier then
17181 D := First_Discriminant (Typ_For_Constraint);
17182 E := First_Elmt (Constraint);
17183 while Present (D) loop
17184 if Root_Corresponding_Discriminant (D) = Discriminant then
17188 Next_Discriminant (D);
17194 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
17196 end Get_Discriminant_Value;
17198 --------------------------
17199 -- Has_Range_Constraint --
17200 --------------------------
17202 function Has_Range_Constraint (N : Node_Id) return Boolean is
17203 C : constant Node_Id := Constraint (N);
17206 if Nkind (C) = N_Range_Constraint then
17209 elsif Nkind (C) = N_Digits_Constraint then
17211 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
17212 or else Present (Range_Constraint (C));
17214 elsif Nkind (C) = N_Delta_Constraint then
17215 return Present (Range_Constraint (C));
17220 end Has_Range_Constraint;
17222 ------------------------
17223 -- Inherit_Components --
17224 ------------------------
17226 function Inherit_Components
17228 Parent_Base : Entity_Id;
17229 Derived_Base : Entity_Id;
17230 Is_Tagged : Boolean;
17231 Inherit_Discr : Boolean;
17232 Discs : Elist_Id) return Elist_Id
17234 Assoc_List : constant Elist_Id := New_Elmt_List;
17236 procedure Inherit_Component
17237 (Old_C : Entity_Id;
17238 Plain_Discrim : Boolean := False;
17239 Stored_Discrim : Boolean := False);
17240 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
17241 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
17242 -- True, Old_C is a stored discriminant. If they are both false then
17243 -- Old_C is a regular component.
17245 -----------------------
17246 -- Inherit_Component --
17247 -----------------------
17249 procedure Inherit_Component
17250 (Old_C : Entity_Id;
17251 Plain_Discrim : Boolean := False;
17252 Stored_Discrim : Boolean := False)
17254 procedure Set_Anonymous_Type (Id : Entity_Id);
17255 -- Id denotes the entity of an access discriminant or anonymous
17256 -- access component. Set the type of Id to either the same type of
17257 -- Old_C or create a new one depending on whether the parent and
17258 -- the child types are in the same scope.
17260 ------------------------
17261 -- Set_Anonymous_Type --
17262 ------------------------
17264 procedure Set_Anonymous_Type (Id : Entity_Id) is
17265 Old_Typ : constant Entity_Id := Etype (Old_C);
17268 if Scope (Parent_Base) = Scope (Derived_Base) then
17269 Set_Etype (Id, Old_Typ);
17271 -- The parent and the derived type are in two different scopes.
17272 -- Reuse the type of the original discriminant / component by
17273 -- copying it in order to preserve all attributes.
17277 Typ : constant Entity_Id := New_Copy (Old_Typ);
17280 Set_Etype (Id, Typ);
17282 -- Since we do not generate component declarations for
17283 -- inherited components, associate the itype with the
17286 Set_Associated_Node_For_Itype (Typ, Parent (Derived_Base));
17287 Set_Scope (Typ, Derived_Base);
17290 end Set_Anonymous_Type;
17292 -- Local variables and constants
17294 New_C : constant Entity_Id := New_Copy (Old_C);
17296 Corr_Discrim : Entity_Id;
17297 Discrim : Entity_Id;
17299 -- Start of processing for Inherit_Component
17302 pragma Assert (not Is_Tagged or not Stored_Discrim);
17304 Set_Parent (New_C, Parent (Old_C));
17306 -- Regular discriminants and components must be inserted in the scope
17307 -- of the Derived_Base. Do it here.
17309 if not Stored_Discrim then
17310 Enter_Name (New_C);
17313 -- For tagged types the Original_Record_Component must point to
17314 -- whatever this field was pointing to in the parent type. This has
17315 -- already been achieved by the call to New_Copy above.
17317 if not Is_Tagged then
17318 Set_Original_Record_Component (New_C, New_C);
17321 -- Set the proper type of an access discriminant
17323 if Ekind (New_C) = E_Discriminant
17324 and then Ekind (Etype (New_C)) = E_Anonymous_Access_Type
17326 Set_Anonymous_Type (New_C);
17329 -- If we have inherited a component then see if its Etype contains
17330 -- references to Parent_Base discriminants. In this case, replace
17331 -- these references with the constraints given in Discs. We do not
17332 -- do this for the partial view of private types because this is
17333 -- not needed (only the components of the full view will be used
17334 -- for code generation) and cause problem. We also avoid this
17335 -- transformation in some error situations.
17337 if Ekind (New_C) = E_Component then
17339 -- Set the proper type of an anonymous access component
17341 if Ekind (Etype (New_C)) = E_Anonymous_Access_Type then
17342 Set_Anonymous_Type (New_C);
17344 elsif (Is_Private_Type (Derived_Base)
17345 and then not Is_Generic_Type (Derived_Base))
17346 or else (Is_Empty_Elmt_List (Discs)
17347 and then not Expander_Active)
17349 Set_Etype (New_C, Etype (Old_C));
17352 -- The current component introduces a circularity of the
17355 -- limited with Pack_2;
17356 -- package Pack_1 is
17357 -- type T_1 is tagged record
17358 -- Comp : access Pack_2.T_2;
17364 -- package Pack_2 is
17365 -- type T_2 is new Pack_1.T_1 with ...;
17370 Constrain_Component_Type
17371 (Old_C, Derived_Base, N, Parent_Base, Discs));
17375 -- In derived tagged types it is illegal to reference a non
17376 -- discriminant component in the parent type. To catch this, mark
17377 -- these components with an Ekind of E_Void. This will be reset in
17378 -- Record_Type_Definition after processing the record extension of
17379 -- the derived type.
17381 -- If the declaration is a private extension, there is no further
17382 -- record extension to process, and the components retain their
17383 -- current kind, because they are visible at this point.
17385 if Is_Tagged and then Ekind (New_C) = E_Component
17386 and then Nkind (N) /= N_Private_Extension_Declaration
17388 Set_Ekind (New_C, E_Void);
17391 if Plain_Discrim then
17392 Set_Corresponding_Discriminant (New_C, Old_C);
17393 Build_Discriminal (New_C);
17395 -- If we are explicitly inheriting a stored discriminant it will be
17396 -- completely hidden.
17398 elsif Stored_Discrim then
17399 Set_Corresponding_Discriminant (New_C, Empty);
17400 Set_Discriminal (New_C, Empty);
17401 Set_Is_Completely_Hidden (New_C);
17403 -- Set the Original_Record_Component of each discriminant in the
17404 -- derived base to point to the corresponding stored that we just
17407 Discrim := First_Discriminant (Derived_Base);
17408 while Present (Discrim) loop
17409 Corr_Discrim := Corresponding_Discriminant (Discrim);
17411 -- Corr_Discrim could be missing in an error situation
17413 if Present (Corr_Discrim)
17414 and then Original_Record_Component (Corr_Discrim) = Old_C
17416 Set_Original_Record_Component (Discrim, New_C);
17419 Next_Discriminant (Discrim);
17422 Append_Entity (New_C, Derived_Base);
17425 if not Is_Tagged then
17426 Append_Elmt (Old_C, Assoc_List);
17427 Append_Elmt (New_C, Assoc_List);
17429 end Inherit_Component;
17431 -- Variables local to Inherit_Component
17433 Loc : constant Source_Ptr := Sloc (N);
17435 Parent_Discrim : Entity_Id;
17436 Stored_Discrim : Entity_Id;
17438 Component : Entity_Id;
17440 -- Start of processing for Inherit_Components
17443 if not Is_Tagged then
17444 Append_Elmt (Parent_Base, Assoc_List);
17445 Append_Elmt (Derived_Base, Assoc_List);
17448 -- Inherit parent discriminants if needed
17450 if Inherit_Discr then
17451 Parent_Discrim := First_Discriminant (Parent_Base);
17452 while Present (Parent_Discrim) loop
17453 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
17454 Next_Discriminant (Parent_Discrim);
17458 -- Create explicit stored discrims for untagged types when necessary
17460 if not Has_Unknown_Discriminants (Derived_Base)
17461 and then Has_Discriminants (Parent_Base)
17462 and then not Is_Tagged
17465 or else First_Discriminant (Parent_Base) /=
17466 First_Stored_Discriminant (Parent_Base))
17468 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
17469 while Present (Stored_Discrim) loop
17470 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
17471 Next_Stored_Discriminant (Stored_Discrim);
17475 -- See if we can apply the second transformation for derived types, as
17476 -- explained in point 6. in the comments above Build_Derived_Record_Type
17477 -- This is achieved by appending Derived_Base discriminants into Discs,
17478 -- which has the side effect of returning a non empty Discs list to the
17479 -- caller of Inherit_Components, which is what we want. This must be
17480 -- done for private derived types if there are explicit stored
17481 -- discriminants, to ensure that we can retrieve the values of the
17482 -- constraints provided in the ancestors.
17485 and then Is_Empty_Elmt_List (Discs)
17486 and then Present (First_Discriminant (Derived_Base))
17488 (not Is_Private_Type (Derived_Base)
17489 or else Is_Completely_Hidden
17490 (First_Stored_Discriminant (Derived_Base))
17491 or else Is_Generic_Type (Derived_Base))
17493 D := First_Discriminant (Derived_Base);
17494 while Present (D) loop
17495 Append_Elmt (New_Occurrence_Of (D, Loc), Discs);
17496 Next_Discriminant (D);
17500 -- Finally, inherit non-discriminant components unless they are not
17501 -- visible because defined or inherited from the full view of the
17502 -- parent. Don't inherit the _parent field of the parent type.
17504 Component := First_Entity (Parent_Base);
17505 while Present (Component) loop
17507 -- Ada 2005 (AI-251): Do not inherit components associated with
17508 -- secondary tags of the parent.
17510 if Ekind (Component) = E_Component
17511 and then Present (Related_Type (Component))
17515 elsif Ekind (Component) /= E_Component
17516 or else Chars (Component) = Name_uParent
17520 -- If the derived type is within the parent type's declarative
17521 -- region, then the components can still be inherited even though
17522 -- they aren't visible at this point. This can occur for cases
17523 -- such as within public child units where the components must
17524 -- become visible upon entering the child unit's private part.
17526 elsif not Is_Visible_Component (Component)
17527 and then not In_Open_Scopes (Scope (Parent_Base))
17531 elsif Ekind_In (Derived_Base, E_Private_Type,
17532 E_Limited_Private_Type)
17537 Inherit_Component (Component);
17540 Next_Entity (Component);
17543 -- For tagged derived types, inherited discriminants cannot be used in
17544 -- component declarations of the record extension part. To achieve this
17545 -- we mark the inherited discriminants as not visible.
17547 if Is_Tagged and then Inherit_Discr then
17548 D := First_Discriminant (Derived_Base);
17549 while Present (D) loop
17550 Set_Is_Immediately_Visible (D, False);
17551 Next_Discriminant (D);
17556 end Inherit_Components;
17558 -----------------------------
17559 -- Inherit_Predicate_Flags --
17560 -----------------------------
17562 procedure Inherit_Predicate_Flags (Subt, Par : Entity_Id) is
17564 Set_Has_Predicates (Subt, Has_Predicates (Par));
17565 Set_Has_Static_Predicate_Aspect
17566 (Subt, Has_Static_Predicate_Aspect (Par));
17567 Set_Has_Dynamic_Predicate_Aspect
17568 (Subt, Has_Dynamic_Predicate_Aspect (Par));
17569 end Inherit_Predicate_Flags;
17571 ----------------------
17572 -- Is_EVF_Procedure --
17573 ----------------------
17575 function Is_EVF_Procedure (Subp : Entity_Id) return Boolean is
17576 Formal : Entity_Id;
17579 -- Examine the formals of an Extensions_Visible False procedure looking
17580 -- for a controlling OUT parameter.
17582 if Ekind (Subp) = E_Procedure
17583 and then Extensions_Visible_Status (Subp) = Extensions_Visible_False
17585 Formal := First_Formal (Subp);
17586 while Present (Formal) loop
17587 if Ekind (Formal) = E_Out_Parameter
17588 and then Is_Controlling_Formal (Formal)
17593 Next_Formal (Formal);
17598 end Is_EVF_Procedure;
17600 -----------------------
17601 -- Is_Null_Extension --
17602 -----------------------
17604 function Is_Null_Extension (T : Entity_Id) return Boolean is
17605 Type_Decl : constant Node_Id := Parent (Base_Type (T));
17606 Comp_List : Node_Id;
17610 if Nkind (Type_Decl) /= N_Full_Type_Declaration
17611 or else not Is_Tagged_Type (T)
17612 or else Nkind (Type_Definition (Type_Decl)) /=
17613 N_Derived_Type_Definition
17614 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
17620 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
17622 if Present (Discriminant_Specifications (Type_Decl)) then
17625 elsif Present (Comp_List)
17626 and then Is_Non_Empty_List (Component_Items (Comp_List))
17628 Comp := First (Component_Items (Comp_List));
17630 -- Only user-defined components are relevant. The component list
17631 -- may also contain a parent component and internal components
17632 -- corresponding to secondary tags, but these do not determine
17633 -- whether this is a null extension.
17635 while Present (Comp) loop
17636 if Comes_From_Source (Comp) then
17647 end Is_Null_Extension;
17649 ------------------------------
17650 -- Is_Valid_Constraint_Kind --
17651 ------------------------------
17653 function Is_Valid_Constraint_Kind
17654 (T_Kind : Type_Kind;
17655 Constraint_Kind : Node_Kind) return Boolean
17659 when Enumeration_Kind |
17661 return Constraint_Kind = N_Range_Constraint;
17663 when Decimal_Fixed_Point_Kind =>
17664 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17665 N_Range_Constraint);
17667 when Ordinary_Fixed_Point_Kind =>
17668 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
17669 N_Range_Constraint);
17672 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
17673 N_Range_Constraint);
17680 E_Incomplete_Type |
17683 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
17686 return True; -- Error will be detected later
17688 end Is_Valid_Constraint_Kind;
17690 --------------------------
17691 -- Is_Visible_Component --
17692 --------------------------
17694 function Is_Visible_Component
17696 N : Node_Id := Empty) return Boolean
17698 Original_Comp : Entity_Id := Empty;
17699 Original_Scope : Entity_Id;
17700 Type_Scope : Entity_Id;
17702 function Is_Local_Type (Typ : Entity_Id) return Boolean;
17703 -- Check whether parent type of inherited component is declared locally,
17704 -- possibly within a nested package or instance. The current scope is
17705 -- the derived record itself.
17707 -------------------
17708 -- Is_Local_Type --
17709 -------------------
17711 function Is_Local_Type (Typ : Entity_Id) return Boolean is
17715 Scop := Scope (Typ);
17716 while Present (Scop)
17717 and then Scop /= Standard_Standard
17719 if Scop = Scope (Current_Scope) then
17723 Scop := Scope (Scop);
17729 -- Start of processing for Is_Visible_Component
17732 if Ekind_In (C, E_Component, E_Discriminant) then
17733 Original_Comp := Original_Record_Component (C);
17736 if No (Original_Comp) then
17738 -- Premature usage, or previous error
17743 Original_Scope := Scope (Original_Comp);
17744 Type_Scope := Scope (Base_Type (Scope (C)));
17747 -- This test only concerns tagged types
17749 if not Is_Tagged_Type (Original_Scope) then
17752 -- If it is _Parent or _Tag, there is no visibility issue
17754 elsif not Comes_From_Source (Original_Comp) then
17757 -- Discriminants are visible unless the (private) type has unknown
17758 -- discriminants. If the discriminant reference is inserted for a
17759 -- discriminant check on a full view it is also visible.
17761 elsif Ekind (Original_Comp) = E_Discriminant
17763 (not Has_Unknown_Discriminants (Original_Scope)
17764 or else (Present (N)
17765 and then Nkind (N) = N_Selected_Component
17766 and then Nkind (Prefix (N)) = N_Type_Conversion
17767 and then not Comes_From_Source (Prefix (N))))
17771 -- In the body of an instantiation, no need to check for the visibility
17774 elsif In_Instance_Body then
17777 -- If the component has been declared in an ancestor which is currently
17778 -- a private type, then it is not visible. The same applies if the
17779 -- component's containing type is not in an open scope and the original
17780 -- component's enclosing type is a visible full view of a private type
17781 -- (which can occur in cases where an attempt is being made to reference
17782 -- a component in a sibling package that is inherited from a visible
17783 -- component of a type in an ancestor package; the component in the
17784 -- sibling package should not be visible even though the component it
17785 -- inherited from is visible). This does not apply however in the case
17786 -- where the scope of the type is a private child unit, or when the
17787 -- parent comes from a local package in which the ancestor is currently
17788 -- visible. The latter suppression of visibility is needed for cases
17789 -- that are tested in B730006.
17791 elsif Is_Private_Type (Original_Scope)
17793 (not Is_Private_Descendant (Type_Scope)
17794 and then not In_Open_Scopes (Type_Scope)
17795 and then Has_Private_Declaration (Original_Scope))
17797 -- If the type derives from an entity in a formal package, there
17798 -- are no additional visible components.
17800 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
17801 N_Formal_Package_Declaration
17805 -- if we are not in the private part of the current package, there
17806 -- are no additional visible components.
17808 elsif Ekind (Scope (Current_Scope)) = E_Package
17809 and then not In_Private_Part (Scope (Current_Scope))
17814 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
17815 and then In_Open_Scopes (Scope (Original_Scope))
17816 and then Is_Local_Type (Type_Scope);
17819 -- There is another weird way in which a component may be invisible when
17820 -- the private and the full view are not derived from the same ancestor.
17821 -- Here is an example :
17823 -- type A1 is tagged record F1 : integer; end record;
17824 -- type A2 is new A1 with record F2 : integer; end record;
17825 -- type T is new A1 with private;
17827 -- type T is new A2 with null record;
17829 -- In this case, the full view of T inherits F1 and F2 but the private
17830 -- view inherits only F1
17834 Ancestor : Entity_Id := Scope (C);
17838 if Ancestor = Original_Scope then
17840 elsif Ancestor = Etype (Ancestor) then
17844 Ancestor := Etype (Ancestor);
17848 end Is_Visible_Component;
17850 --------------------------
17851 -- Make_Class_Wide_Type --
17852 --------------------------
17854 procedure Make_Class_Wide_Type (T : Entity_Id) is
17855 CW_Type : Entity_Id;
17857 Next_E : Entity_Id;
17860 if Present (Class_Wide_Type (T)) then
17862 -- The class-wide type is a partially decorated entity created for a
17863 -- unanalyzed tagged type referenced through a limited with clause.
17864 -- When the tagged type is analyzed, its class-wide type needs to be
17865 -- redecorated. Note that we reuse the entity created by Decorate_
17866 -- Tagged_Type in order to preserve all links.
17868 if Materialize_Entity (Class_Wide_Type (T)) then
17869 CW_Type := Class_Wide_Type (T);
17870 Set_Materialize_Entity (CW_Type, False);
17872 -- The class wide type can have been defined by the partial view, in
17873 -- which case everything is already done.
17879 -- Default case, we need to create a new class-wide type
17883 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
17886 -- Inherit root type characteristics
17888 CW_Name := Chars (CW_Type);
17889 Next_E := Next_Entity (CW_Type);
17890 Copy_Node (T, CW_Type);
17891 Set_Comes_From_Source (CW_Type, False);
17892 Set_Chars (CW_Type, CW_Name);
17893 Set_Parent (CW_Type, Parent (T));
17894 Set_Next_Entity (CW_Type, Next_E);
17896 -- Ensure we have a new freeze node for the class-wide type. The partial
17897 -- view may have freeze action of its own, requiring a proper freeze
17898 -- node, and the same freeze node cannot be shared between the two
17901 Set_Has_Delayed_Freeze (CW_Type);
17902 Set_Freeze_Node (CW_Type, Empty);
17904 -- Customize the class-wide type: It has no prim. op., it cannot be
17905 -- abstract and its Etype points back to the specific root type.
17907 Set_Ekind (CW_Type, E_Class_Wide_Type);
17908 Set_Is_Tagged_Type (CW_Type, True);
17909 Set_Direct_Primitive_Operations (CW_Type, New_Elmt_List);
17910 Set_Is_Abstract_Type (CW_Type, False);
17911 Set_Is_Constrained (CW_Type, False);
17912 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
17913 Set_Default_SSO (CW_Type);
17915 if Ekind (T) = E_Class_Wide_Subtype then
17916 Set_Etype (CW_Type, Etype (Base_Type (T)));
17918 Set_Etype (CW_Type, T);
17921 Set_No_Tagged_Streams_Pragma (CW_Type, No_Tagged_Streams);
17923 -- If this is the class_wide type of a constrained subtype, it does
17924 -- not have discriminants.
17926 Set_Has_Discriminants (CW_Type,
17927 Has_Discriminants (T) and then not Is_Constrained (T));
17929 Set_Has_Unknown_Discriminants (CW_Type, True);
17930 Set_Class_Wide_Type (T, CW_Type);
17931 Set_Equivalent_Type (CW_Type, Empty);
17933 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
17935 Set_Class_Wide_Type (CW_Type, CW_Type);
17936 end Make_Class_Wide_Type;
17942 procedure Make_Index
17944 Related_Nod : Node_Id;
17945 Related_Id : Entity_Id := Empty;
17946 Suffix_Index : Nat := 1;
17947 In_Iter_Schm : Boolean := False)
17951 Def_Id : Entity_Id := Empty;
17952 Found : Boolean := False;
17955 -- For a discrete range used in a constrained array definition and
17956 -- defined by a range, an implicit conversion to the predefined type
17957 -- INTEGER is assumed if each bound is either a numeric literal, a named
17958 -- number, or an attribute, and the type of both bounds (prior to the
17959 -- implicit conversion) is the type universal_integer. Otherwise, both
17960 -- bounds must be of the same discrete type, other than universal
17961 -- integer; this type must be determinable independently of the
17962 -- context, but using the fact that the type must be discrete and that
17963 -- both bounds must have the same type.
17965 -- Character literals also have a universal type in the absence of
17966 -- of additional context, and are resolved to Standard_Character.
17968 if Nkind (N) = N_Range then
17970 -- The index is given by a range constraint. The bounds are known
17971 -- to be of a consistent type.
17973 if not Is_Overloaded (N) then
17976 -- For universal bounds, choose the specific predefined type
17978 if T = Universal_Integer then
17979 T := Standard_Integer;
17981 elsif T = Any_Character then
17982 Ambiguous_Character (Low_Bound (N));
17984 T := Standard_Character;
17987 -- The node may be overloaded because some user-defined operators
17988 -- are available, but if a universal interpretation exists it is
17989 -- also the selected one.
17991 elsif Universal_Interpretation (N) = Universal_Integer then
17992 T := Standard_Integer;
17998 Ind : Interp_Index;
18002 Get_First_Interp (N, Ind, It);
18003 while Present (It.Typ) loop
18004 if Is_Discrete_Type (It.Typ) then
18007 and then not Covers (It.Typ, T)
18008 and then not Covers (T, It.Typ)
18010 Error_Msg_N ("ambiguous bounds in discrete range", N);
18018 Get_Next_Interp (Ind, It);
18021 if T = Any_Type then
18022 Error_Msg_N ("discrete type required for range", N);
18023 Set_Etype (N, Any_Type);
18026 elsif T = Universal_Integer then
18027 T := Standard_Integer;
18032 if not Is_Discrete_Type (T) then
18033 Error_Msg_N ("discrete type required for range", N);
18034 Set_Etype (N, Any_Type);
18038 if Nkind (Low_Bound (N)) = N_Attribute_Reference
18039 and then Attribute_Name (Low_Bound (N)) = Name_First
18040 and then Is_Entity_Name (Prefix (Low_Bound (N)))
18041 and then Is_Type (Entity (Prefix (Low_Bound (N))))
18042 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (N))))
18044 -- The type of the index will be the type of the prefix, as long
18045 -- as the upper bound is 'Last of the same type.
18047 Def_Id := Entity (Prefix (Low_Bound (N)));
18049 if Nkind (High_Bound (N)) /= N_Attribute_Reference
18050 or else Attribute_Name (High_Bound (N)) /= Name_Last
18051 or else not Is_Entity_Name (Prefix (High_Bound (N)))
18052 or else Entity (Prefix (High_Bound (N))) /= Def_Id
18059 Process_Range_Expr_In_Decl (R, T, In_Iter_Schm => In_Iter_Schm);
18061 elsif Nkind (N) = N_Subtype_Indication then
18063 -- The index is given by a subtype with a range constraint
18065 T := Base_Type (Entity (Subtype_Mark (N)));
18067 if not Is_Discrete_Type (T) then
18068 Error_Msg_N ("discrete type required for range", N);
18069 Set_Etype (N, Any_Type);
18073 R := Range_Expression (Constraint (N));
18076 Process_Range_Expr_In_Decl
18077 (R, Entity (Subtype_Mark (N)), In_Iter_Schm => In_Iter_Schm);
18079 elsif Nkind (N) = N_Attribute_Reference then
18081 -- Catch beginner's error (use of attribute other than 'Range)
18083 if Attribute_Name (N) /= Name_Range then
18084 Error_Msg_N ("expect attribute ''Range", N);
18085 Set_Etype (N, Any_Type);
18089 -- If the node denotes the range of a type mark, that is also the
18090 -- resulting type, and we do not need to create an Itype for it.
18092 if Is_Entity_Name (Prefix (N))
18093 and then Comes_From_Source (N)
18094 and then Is_Type (Entity (Prefix (N)))
18095 and then Is_Discrete_Type (Entity (Prefix (N)))
18097 Def_Id := Entity (Prefix (N));
18100 Analyze_And_Resolve (N);
18104 -- If none of the above, must be a subtype. We convert this to a
18105 -- range attribute reference because in the case of declared first
18106 -- named subtypes, the types in the range reference can be different
18107 -- from the type of the entity. A range attribute normalizes the
18108 -- reference and obtains the correct types for the bounds.
18110 -- This transformation is in the nature of an expansion, is only
18111 -- done if expansion is active. In particular, it is not done on
18112 -- formal generic types, because we need to retain the name of the
18113 -- original index for instantiation purposes.
18116 if not Is_Entity_Name (N) or else not Is_Type (Entity (N)) then
18117 Error_Msg_N ("invalid subtype mark in discrete range ", N);
18118 Set_Etype (N, Any_Integer);
18122 -- The type mark may be that of an incomplete type. It is only
18123 -- now that we can get the full view, previous analysis does
18124 -- not look specifically for a type mark.
18126 Set_Entity (N, Get_Full_View (Entity (N)));
18127 Set_Etype (N, Entity (N));
18128 Def_Id := Entity (N);
18130 if not Is_Discrete_Type (Def_Id) then
18131 Error_Msg_N ("discrete type required for index", N);
18132 Set_Etype (N, Any_Type);
18137 if Expander_Active then
18139 Make_Attribute_Reference (Sloc (N),
18140 Attribute_Name => Name_Range,
18141 Prefix => Relocate_Node (N)));
18143 -- The original was a subtype mark that does not freeze. This
18144 -- means that the rewritten version must not freeze either.
18146 Set_Must_Not_Freeze (N);
18147 Set_Must_Not_Freeze (Prefix (N));
18148 Analyze_And_Resolve (N);
18152 -- If expander is inactive, type is legal, nothing else to construct
18159 if not Is_Discrete_Type (T) then
18160 Error_Msg_N ("discrete type required for range", N);
18161 Set_Etype (N, Any_Type);
18164 elsif T = Any_Type then
18165 Set_Etype (N, Any_Type);
18169 -- We will now create the appropriate Itype to describe the range, but
18170 -- first a check. If we originally had a subtype, then we just label
18171 -- the range with this subtype. Not only is there no need to construct
18172 -- a new subtype, but it is wrong to do so for two reasons:
18174 -- 1. A legality concern, if we have a subtype, it must not freeze,
18175 -- and the Itype would cause freezing incorrectly
18177 -- 2. An efficiency concern, if we created an Itype, it would not be
18178 -- recognized as the same type for the purposes of eliminating
18179 -- checks in some circumstances.
18181 -- We signal this case by setting the subtype entity in Def_Id
18183 if No (Def_Id) then
18185 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
18186 Set_Etype (Def_Id, Base_Type (T));
18188 if Is_Signed_Integer_Type (T) then
18189 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
18191 elsif Is_Modular_Integer_Type (T) then
18192 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
18195 Set_Ekind (Def_Id, E_Enumeration_Subtype);
18196 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
18197 Set_First_Literal (Def_Id, First_Literal (T));
18200 Set_Size_Info (Def_Id, (T));
18201 Set_RM_Size (Def_Id, RM_Size (T));
18202 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
18204 Set_Scalar_Range (Def_Id, R);
18205 Conditional_Delay (Def_Id, T);
18207 if Nkind (N) = N_Subtype_Indication then
18208 Inherit_Predicate_Flags (Def_Id, Entity (Subtype_Mark (N)));
18211 -- In the subtype indication case, if the immediate parent of the
18212 -- new subtype is non-static, then the subtype we create is non-
18213 -- static, even if its bounds are static.
18215 if Nkind (N) = N_Subtype_Indication
18216 and then not Is_OK_Static_Subtype (Entity (Subtype_Mark (N)))
18218 Set_Is_Non_Static_Subtype (Def_Id);
18222 -- Final step is to label the index with this constructed type
18224 Set_Etype (N, Def_Id);
18227 ------------------------------
18228 -- Modular_Type_Declaration --
18229 ------------------------------
18231 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
18232 Mod_Expr : constant Node_Id := Expression (Def);
18235 procedure Set_Modular_Size (Bits : Int);
18236 -- Sets RM_Size to Bits, and Esize to normal word size above this
18238 ----------------------
18239 -- Set_Modular_Size --
18240 ----------------------
18242 procedure Set_Modular_Size (Bits : Int) is
18244 Set_RM_Size (T, UI_From_Int (Bits));
18249 elsif Bits <= 16 then
18250 Init_Esize (T, 16);
18252 elsif Bits <= 32 then
18253 Init_Esize (T, 32);
18256 Init_Esize (T, System_Max_Binary_Modulus_Power);
18259 if not Non_Binary_Modulus (T)
18260 and then Esize (T) = RM_Size (T)
18262 Set_Is_Known_Valid (T);
18264 end Set_Modular_Size;
18266 -- Start of processing for Modular_Type_Declaration
18269 -- If the mod expression is (exactly) 2 * literal, where literal is
18270 -- 64 or less,then almost certainly the * was meant to be **. Warn.
18272 if Warn_On_Suspicious_Modulus_Value
18273 and then Nkind (Mod_Expr) = N_Op_Multiply
18274 and then Nkind (Left_Opnd (Mod_Expr)) = N_Integer_Literal
18275 and then Intval (Left_Opnd (Mod_Expr)) = Uint_2
18276 and then Nkind (Right_Opnd (Mod_Expr)) = N_Integer_Literal
18277 and then Intval (Right_Opnd (Mod_Expr)) <= Uint_64
18280 ("suspicious MOD value, was '*'* intended'??M?", Mod_Expr);
18283 -- Proceed with analysis of mod expression
18285 Analyze_And_Resolve (Mod_Expr, Any_Integer);
18287 Set_Ekind (T, E_Modular_Integer_Type);
18288 Init_Alignment (T);
18289 Set_Is_Constrained (T);
18291 if not Is_OK_Static_Expression (Mod_Expr) then
18292 Flag_Non_Static_Expr
18293 ("non-static expression used for modular type bound!", Mod_Expr);
18294 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18296 M_Val := Expr_Value (Mod_Expr);
18300 Error_Msg_N ("modulus value must be positive", Mod_Expr);
18301 M_Val := 2 ** System_Max_Binary_Modulus_Power;
18304 if M_Val > 2 ** Standard_Long_Integer_Size then
18305 Check_Restriction (No_Long_Long_Integers, Mod_Expr);
18308 Set_Modulus (T, M_Val);
18310 -- Create bounds for the modular type based on the modulus given in
18311 -- the type declaration and then analyze and resolve those bounds.
18313 Set_Scalar_Range (T,
18314 Make_Range (Sloc (Mod_Expr),
18315 Low_Bound => Make_Integer_Literal (Sloc (Mod_Expr), 0),
18316 High_Bound => Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
18318 -- Properly analyze the literals for the range. We do this manually
18319 -- because we can't go calling Resolve, since we are resolving these
18320 -- bounds with the type, and this type is certainly not complete yet.
18322 Set_Etype (Low_Bound (Scalar_Range (T)), T);
18323 Set_Etype (High_Bound (Scalar_Range (T)), T);
18324 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
18325 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
18327 -- Loop through powers of two to find number of bits required
18329 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
18333 if M_Val = 2 ** Bits then
18334 Set_Modular_Size (Bits);
18339 elsif M_Val < 2 ** Bits then
18340 Check_SPARK_05_Restriction ("modulus should be a power of 2", T);
18341 Set_Non_Binary_Modulus (T);
18343 if Bits > System_Max_Nonbinary_Modulus_Power then
18344 Error_Msg_Uint_1 :=
18345 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
18347 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
18348 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18352 -- In the non-binary case, set size as per RM 13.3(55)
18354 Set_Modular_Size (Bits);
18361 -- If we fall through, then the size exceed System.Max_Binary_Modulus
18362 -- so we just signal an error and set the maximum size.
18364 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
18365 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
18367 Set_Modular_Size (System_Max_Binary_Modulus_Power);
18368 Init_Alignment (T);
18370 end Modular_Type_Declaration;
18372 --------------------------
18373 -- New_Concatenation_Op --
18374 --------------------------
18376 procedure New_Concatenation_Op (Typ : Entity_Id) is
18377 Loc : constant Source_Ptr := Sloc (Typ);
18380 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
18381 -- Create abbreviated declaration for the formal of a predefined
18382 -- Operator 'Op' of type 'Typ'
18384 --------------------
18385 -- Make_Op_Formal --
18386 --------------------
18388 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
18389 Formal : Entity_Id;
18391 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
18392 Set_Etype (Formal, Typ);
18393 Set_Mechanism (Formal, Default_Mechanism);
18395 end Make_Op_Formal;
18397 -- Start of processing for New_Concatenation_Op
18400 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
18402 Set_Ekind (Op, E_Operator);
18403 Set_Scope (Op, Current_Scope);
18404 Set_Etype (Op, Typ);
18405 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
18406 Set_Is_Immediately_Visible (Op);
18407 Set_Is_Intrinsic_Subprogram (Op);
18408 Set_Has_Completion (Op);
18409 Append_Entity (Op, Current_Scope);
18411 Set_Name_Entity_Id (Name_Op_Concat, Op);
18413 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18414 Append_Entity (Make_Op_Formal (Typ, Op), Op);
18415 end New_Concatenation_Op;
18417 -------------------------
18418 -- OK_For_Limited_Init --
18419 -------------------------
18421 -- ???Check all calls of this, and compare the conditions under which it's
18424 function OK_For_Limited_Init
18426 Exp : Node_Id) return Boolean
18429 return Is_CPP_Constructor_Call (Exp)
18430 or else (Ada_Version >= Ada_2005
18431 and then not Debug_Flag_Dot_L
18432 and then OK_For_Limited_Init_In_05 (Typ, Exp));
18433 end OK_For_Limited_Init;
18435 -------------------------------
18436 -- OK_For_Limited_Init_In_05 --
18437 -------------------------------
18439 function OK_For_Limited_Init_In_05
18441 Exp : Node_Id) return Boolean
18444 -- An object of a limited interface type can be initialized with any
18445 -- expression of a nonlimited descendant type.
18447 if Is_Class_Wide_Type (Typ)
18448 and then Is_Limited_Interface (Typ)
18449 and then not Is_Limited_Type (Etype (Exp))
18454 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
18455 -- case of limited aggregates (including extension aggregates), and
18456 -- function calls. The function call may have been given in prefixed
18457 -- notation, in which case the original node is an indexed component.
18458 -- If the function is parameterless, the original node was an explicit
18459 -- dereference. The function may also be parameterless, in which case
18460 -- the source node is just an identifier.
18462 case Nkind (Original_Node (Exp)) is
18463 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
18466 when N_Identifier =>
18467 return Present (Entity (Original_Node (Exp)))
18468 and then Ekind (Entity (Original_Node (Exp))) = E_Function;
18470 when N_Qualified_Expression =>
18472 OK_For_Limited_Init_In_05
18473 (Typ, Expression (Original_Node (Exp)));
18475 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
18476 -- with a function call, the expander has rewritten the call into an
18477 -- N_Type_Conversion node to force displacement of the pointer to
18478 -- reference the component containing the secondary dispatch table.
18479 -- Otherwise a type conversion is not a legal context.
18480 -- A return statement for a build-in-place function returning a
18481 -- synchronized type also introduces an unchecked conversion.
18483 when N_Type_Conversion |
18484 N_Unchecked_Type_Conversion =>
18485 return not Comes_From_Source (Exp)
18487 OK_For_Limited_Init_In_05
18488 (Typ, Expression (Original_Node (Exp)));
18490 when N_Indexed_Component |
18491 N_Selected_Component |
18492 N_Explicit_Dereference =>
18493 return Nkind (Exp) = N_Function_Call;
18495 -- A use of 'Input is a function call, hence allowed. Normally the
18496 -- attribute will be changed to a call, but the attribute by itself
18497 -- can occur with -gnatc.
18499 when N_Attribute_Reference =>
18500 return Attribute_Name (Original_Node (Exp)) = Name_Input;
18502 -- For a case expression, all dependent expressions must be legal
18504 when N_Case_Expression =>
18509 Alt := First (Alternatives (Original_Node (Exp)));
18510 while Present (Alt) loop
18511 if not OK_For_Limited_Init_In_05 (Typ, Expression (Alt)) then
18521 -- For an if expression, all dependent expressions must be legal
18523 when N_If_Expression =>
18525 Then_Expr : constant Node_Id :=
18526 Next (First (Expressions (Original_Node (Exp))));
18527 Else_Expr : constant Node_Id := Next (Then_Expr);
18529 return OK_For_Limited_Init_In_05 (Typ, Then_Expr)
18531 OK_For_Limited_Init_In_05 (Typ, Else_Expr);
18537 end OK_For_Limited_Init_In_05;
18539 -------------------------------------------
18540 -- Ordinary_Fixed_Point_Type_Declaration --
18541 -------------------------------------------
18543 procedure Ordinary_Fixed_Point_Type_Declaration
18547 Loc : constant Source_Ptr := Sloc (Def);
18548 Delta_Expr : constant Node_Id := Delta_Expression (Def);
18549 RRS : constant Node_Id := Real_Range_Specification (Def);
18550 Implicit_Base : Entity_Id;
18557 Check_Restriction (No_Fixed_Point, Def);
18559 -- Create implicit base type
18562 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
18563 Set_Etype (Implicit_Base, Implicit_Base);
18565 -- Analyze and process delta expression
18567 Analyze_And_Resolve (Delta_Expr, Any_Real);
18569 Check_Delta_Expression (Delta_Expr);
18570 Delta_Val := Expr_Value_R (Delta_Expr);
18572 Set_Delta_Value (Implicit_Base, Delta_Val);
18574 -- Compute default small from given delta, which is the largest power
18575 -- of two that does not exceed the given delta value.
18585 if Delta_Val < Ureal_1 then
18586 while Delta_Val < Tmp loop
18587 Tmp := Tmp / Ureal_2;
18588 Scale := Scale + 1;
18593 Tmp := Tmp * Ureal_2;
18594 exit when Tmp > Delta_Val;
18595 Scale := Scale - 1;
18599 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
18602 Set_Small_Value (Implicit_Base, Small_Val);
18604 -- If no range was given, set a dummy range
18606 if RRS <= Empty_Or_Error then
18607 Low_Val := -Small_Val;
18608 High_Val := Small_Val;
18610 -- Otherwise analyze and process given range
18614 Low : constant Node_Id := Low_Bound (RRS);
18615 High : constant Node_Id := High_Bound (RRS);
18618 Analyze_And_Resolve (Low, Any_Real);
18619 Analyze_And_Resolve (High, Any_Real);
18620 Check_Real_Bound (Low);
18621 Check_Real_Bound (High);
18623 -- Obtain and set the range
18625 Low_Val := Expr_Value_R (Low);
18626 High_Val := Expr_Value_R (High);
18628 if Low_Val > High_Val then
18629 Error_Msg_NE ("??fixed point type& has null range", Def, T);
18634 -- The range for both the implicit base and the declared first subtype
18635 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
18636 -- set a temporary range in place. Note that the bounds of the base
18637 -- type will be widened to be symmetrical and to fill the available
18638 -- bits when the type is frozen.
18640 -- We could do this with all discrete types, and probably should, but
18641 -- we absolutely have to do it for fixed-point, since the end-points
18642 -- of the range and the size are determined by the small value, which
18643 -- could be reset before the freeze point.
18645 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
18646 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
18648 -- Complete definition of first subtype. The inheritance of the rep item
18649 -- chain ensures that SPARK-related pragmas are not clobbered when the
18650 -- ordinary fixed point type acts as a full view of a private type.
18652 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
18653 Set_Etype (T, Implicit_Base);
18654 Init_Size_Align (T);
18655 Inherit_Rep_Item_Chain (T, Implicit_Base);
18656 Set_Small_Value (T, Small_Val);
18657 Set_Delta_Value (T, Delta_Val);
18658 Set_Is_Constrained (T);
18659 end Ordinary_Fixed_Point_Type_Declaration;
18661 ----------------------------------
18662 -- Preanalyze_Assert_Expression --
18663 ----------------------------------
18665 procedure Preanalyze_Assert_Expression (N : Node_Id; T : Entity_Id) is
18667 In_Assertion_Expr := In_Assertion_Expr + 1;
18668 Preanalyze_Spec_Expression (N, T);
18669 In_Assertion_Expr := In_Assertion_Expr - 1;
18670 end Preanalyze_Assert_Expression;
18672 -----------------------------------
18673 -- Preanalyze_Default_Expression --
18674 -----------------------------------
18676 procedure Preanalyze_Default_Expression (N : Node_Id; T : Entity_Id) is
18677 Save_In_Default_Expr : constant Boolean := In_Default_Expr;
18679 In_Default_Expr := True;
18680 Preanalyze_Spec_Expression (N, T);
18681 In_Default_Expr := Save_In_Default_Expr;
18682 end Preanalyze_Default_Expression;
18684 --------------------------------
18685 -- Preanalyze_Spec_Expression --
18686 --------------------------------
18688 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
18689 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
18691 In_Spec_Expression := True;
18692 Preanalyze_And_Resolve (N, T);
18693 In_Spec_Expression := Save_In_Spec_Expression;
18694 end Preanalyze_Spec_Expression;
18696 ----------------------------------------
18697 -- Prepare_Private_Subtype_Completion --
18698 ----------------------------------------
18700 procedure Prepare_Private_Subtype_Completion
18702 Related_Nod : Node_Id)
18704 Id_B : constant Entity_Id := Base_Type (Id);
18705 Full_B : Entity_Id := Full_View (Id_B);
18709 if Present (Full_B) then
18711 -- Get to the underlying full view if necessary
18713 if Is_Private_Type (Full_B)
18714 and then Present (Underlying_Full_View (Full_B))
18716 Full_B := Underlying_Full_View (Full_B);
18719 -- The Base_Type is already completed, we can complete the subtype
18720 -- now. We have to create a new entity with the same name, Thus we
18721 -- can't use Create_Itype.
18723 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
18724 Set_Is_Itype (Full);
18725 Set_Associated_Node_For_Itype (Full, Related_Nod);
18726 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
18729 -- The parent subtype may be private, but the base might not, in some
18730 -- nested instances. In that case, the subtype does not need to be
18731 -- exchanged. It would still be nice to make private subtypes and their
18732 -- bases consistent at all times ???
18734 if Is_Private_Type (Id_B) then
18735 Append_Elmt (Id, Private_Dependents (Id_B));
18737 end Prepare_Private_Subtype_Completion;
18739 ---------------------------
18740 -- Process_Discriminants --
18741 ---------------------------
18743 procedure Process_Discriminants
18745 Prev : Entity_Id := Empty)
18747 Elist : constant Elist_Id := New_Elmt_List;
18750 Discr_Number : Uint;
18751 Discr_Type : Entity_Id;
18752 Default_Present : Boolean := False;
18753 Default_Not_Present : Boolean := False;
18756 -- A composite type other than an array type can have discriminants.
18757 -- On entry, the current scope is the composite type.
18759 -- The discriminants are initially entered into the scope of the type
18760 -- via Enter_Name with the default Ekind of E_Void to prevent premature
18761 -- use, as explained at the end of this procedure.
18763 Discr := First (Discriminant_Specifications (N));
18764 while Present (Discr) loop
18765 Enter_Name (Defining_Identifier (Discr));
18767 -- For navigation purposes we add a reference to the discriminant
18768 -- in the entity for the type. If the current declaration is a
18769 -- completion, place references on the partial view. Otherwise the
18770 -- type is the current scope.
18772 if Present (Prev) then
18774 -- The references go on the partial view, if present. If the
18775 -- partial view has discriminants, the references have been
18776 -- generated already.
18778 if not Has_Discriminants (Prev) then
18779 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
18783 (Current_Scope, Defining_Identifier (Discr), 'd');
18786 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
18787 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
18789 -- Ada 2005 (AI-254)
18791 if Present (Access_To_Subprogram_Definition
18792 (Discriminant_Type (Discr)))
18793 and then Protected_Present (Access_To_Subprogram_Definition
18794 (Discriminant_Type (Discr)))
18797 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
18801 Find_Type (Discriminant_Type (Discr));
18802 Discr_Type := Etype (Discriminant_Type (Discr));
18804 if Error_Posted (Discriminant_Type (Discr)) then
18805 Discr_Type := Any_Type;
18809 -- Handling of discriminants that are access types
18811 if Is_Access_Type (Discr_Type) then
18813 -- Ada 2005 (AI-230): Access discriminant allowed in non-
18814 -- limited record types
18816 if Ada_Version < Ada_2005 then
18817 Check_Access_Discriminant_Requires_Limited
18818 (Discr, Discriminant_Type (Discr));
18821 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
18823 ("(Ada 83) access discriminant not allowed", Discr);
18826 -- If not access type, must be a discrete type
18828 elsif not Is_Discrete_Type (Discr_Type) then
18830 ("discriminants must have a discrete or access type",
18831 Discriminant_Type (Discr));
18834 Set_Etype (Defining_Identifier (Discr), Discr_Type);
18836 -- If a discriminant specification includes the assignment compound
18837 -- delimiter followed by an expression, the expression is the default
18838 -- expression of the discriminant; the default expression must be of
18839 -- the type of the discriminant. (RM 3.7.1) Since this expression is
18840 -- a default expression, we do the special preanalysis, since this
18841 -- expression does not freeze (see section "Handling of Default and
18842 -- Per-Object Expressions" in spec of package Sem).
18844 if Present (Expression (Discr)) then
18845 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
18849 if Nkind (N) = N_Formal_Type_Declaration then
18851 ("discriminant defaults not allowed for formal type",
18852 Expression (Discr));
18854 -- Flag an error for a tagged type with defaulted discriminants,
18855 -- excluding limited tagged types when compiling for Ada 2012
18856 -- (see AI05-0214).
18858 elsif Is_Tagged_Type (Current_Scope)
18859 and then (not Is_Limited_Type (Current_Scope)
18860 or else Ada_Version < Ada_2012)
18861 and then Comes_From_Source (N)
18863 -- Note: see similar test in Check_Or_Process_Discriminants, to
18864 -- handle the (illegal) case of the completion of an untagged
18865 -- view with discriminants with defaults by a tagged full view.
18866 -- We skip the check if Discr does not come from source, to
18867 -- account for the case of an untagged derived type providing
18868 -- defaults for a renamed discriminant from a private untagged
18869 -- ancestor with a tagged full view (ACATS B460006).
18871 if Ada_Version >= Ada_2012 then
18873 ("discriminants of nonlimited tagged type cannot have"
18875 Expression (Discr));
18878 ("discriminants of tagged type cannot have defaults",
18879 Expression (Discr));
18883 Default_Present := True;
18884 Append_Elmt (Expression (Discr), Elist);
18886 -- Tag the defining identifiers for the discriminants with
18887 -- their corresponding default expressions from the tree.
18889 Set_Discriminant_Default_Value
18890 (Defining_Identifier (Discr), Expression (Discr));
18893 -- In gnatc or gnatprove mode, make sure set Do_Range_Check flag
18894 -- gets set unless we can be sure that no range check is required.
18896 if (GNATprove_Mode or not Expander_Active)
18899 (Expression (Discr), Discr_Type, Assume_Valid => True)
18901 Set_Do_Range_Check (Expression (Discr));
18904 -- No default discriminant value given
18907 Default_Not_Present := True;
18910 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
18911 -- Discr_Type but with the null-exclusion attribute
18913 if Ada_Version >= Ada_2005 then
18915 -- Ada 2005 (AI-231): Static checks
18917 if Can_Never_Be_Null (Discr_Type) then
18918 Null_Exclusion_Static_Checks (Discr);
18920 elsif Is_Access_Type (Discr_Type)
18921 and then Null_Exclusion_Present (Discr)
18923 -- No need to check itypes because in their case this check
18924 -- was done at their point of creation
18926 and then not Is_Itype (Discr_Type)
18928 if Can_Never_Be_Null (Discr_Type) then
18930 ("`NOT NULL` not allowed (& already excludes null)",
18935 Set_Etype (Defining_Identifier (Discr),
18936 Create_Null_Excluding_Itype
18938 Related_Nod => Discr));
18940 -- Check for improper null exclusion if the type is otherwise
18941 -- legal for a discriminant.
18943 elsif Null_Exclusion_Present (Discr)
18944 and then Is_Discrete_Type (Discr_Type)
18947 ("null exclusion can only apply to an access type", Discr);
18950 -- Ada 2005 (AI-402): access discriminants of nonlimited types
18951 -- can't have defaults. Synchronized types, or types that are
18952 -- explicitly limited are fine, but special tests apply to derived
18953 -- types in generics: in a generic body we have to assume the
18954 -- worst, and therefore defaults are not allowed if the parent is
18955 -- a generic formal private type (see ACATS B370001).
18957 if Is_Access_Type (Discr_Type) and then Default_Present then
18958 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
18959 or else Is_Limited_Record (Current_Scope)
18960 or else Is_Concurrent_Type (Current_Scope)
18961 or else Is_Concurrent_Record_Type (Current_Scope)
18962 or else Ekind (Current_Scope) = E_Limited_Private_Type
18964 if not Is_Derived_Type (Current_Scope)
18965 or else not Is_Generic_Type (Etype (Current_Scope))
18966 or else not In_Package_Body (Scope (Etype (Current_Scope)))
18967 or else Limited_Present
18968 (Type_Definition (Parent (Current_Scope)))
18973 Error_Msg_N ("access discriminants of nonlimited types",
18974 Expression (Discr));
18975 Error_Msg_N ("\cannot have defaults", Expression (Discr));
18978 elsif Present (Expression (Discr)) then
18980 ("(Ada 2005) access discriminants of nonlimited types",
18981 Expression (Discr));
18982 Error_Msg_N ("\cannot have defaults", Expression (Discr));
18987 -- A discriminant cannot be effectively volatile. This check is only
18988 -- relevant when SPARK_Mode is on as it is not standard Ada legality
18989 -- rule (SPARK RM 7.1.3(6)).
18992 and then Is_Effectively_Volatile (Defining_Identifier (Discr))
18994 Error_Msg_N ("discriminant cannot be volatile", Discr);
19000 -- An element list consisting of the default expressions of the
19001 -- discriminants is constructed in the above loop and used to set
19002 -- the Discriminant_Constraint attribute for the type. If an object
19003 -- is declared of this (record or task) type without any explicit
19004 -- discriminant constraint given, this element list will form the
19005 -- actual parameters for the corresponding initialization procedure
19008 Set_Discriminant_Constraint (Current_Scope, Elist);
19009 Set_Stored_Constraint (Current_Scope, No_Elist);
19011 -- Default expressions must be provided either for all or for none
19012 -- of the discriminants of a discriminant part. (RM 3.7.1)
19014 if Default_Present and then Default_Not_Present then
19016 ("incomplete specification of defaults for discriminants", N);
19019 -- The use of the name of a discriminant is not allowed in default
19020 -- expressions of a discriminant part if the specification of the
19021 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
19023 -- To detect this, the discriminant names are entered initially with an
19024 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
19025 -- attempt to use a void entity (for example in an expression that is
19026 -- type-checked) produces the error message: premature usage. Now after
19027 -- completing the semantic analysis of the discriminant part, we can set
19028 -- the Ekind of all the discriminants appropriately.
19030 Discr := First (Discriminant_Specifications (N));
19031 Discr_Number := Uint_1;
19032 while Present (Discr) loop
19033 Id := Defining_Identifier (Discr);
19034 Set_Ekind (Id, E_Discriminant);
19035 Init_Component_Location (Id);
19037 Set_Discriminant_Number (Id, Discr_Number);
19039 -- Make sure this is always set, even in illegal programs
19041 Set_Corresponding_Discriminant (Id, Empty);
19043 -- Initialize the Original_Record_Component to the entity itself.
19044 -- Inherit_Components will propagate the right value to
19045 -- discriminants in derived record types.
19047 Set_Original_Record_Component (Id, Id);
19049 -- Create the discriminal for the discriminant
19051 Build_Discriminal (Id);
19054 Discr_Number := Discr_Number + 1;
19057 Set_Has_Discriminants (Current_Scope);
19058 end Process_Discriminants;
19060 -----------------------
19061 -- Process_Full_View --
19062 -----------------------
19064 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
19065 procedure Collect_Implemented_Interfaces
19067 Ifaces : Elist_Id);
19068 -- Ada 2005: Gather all the interfaces that Typ directly or
19069 -- inherently implements. Duplicate entries are not added to
19070 -- the list Ifaces.
19072 ------------------------------------
19073 -- Collect_Implemented_Interfaces --
19074 ------------------------------------
19076 procedure Collect_Implemented_Interfaces
19081 Iface_Elmt : Elmt_Id;
19084 -- Abstract interfaces are only associated with tagged record types
19086 if not Is_Tagged_Type (Typ) or else not Is_Record_Type (Typ) then
19090 -- Recursively climb to the ancestors
19092 if Etype (Typ) /= Typ
19094 -- Protect the frontend against wrong cyclic declarations like:
19096 -- type B is new A with private;
19097 -- type C is new A with private;
19099 -- type B is new C with null record;
19100 -- type C is new B with null record;
19102 and then Etype (Typ) /= Priv_T
19103 and then Etype (Typ) /= Full_T
19105 -- Keep separate the management of private type declarations
19107 if Ekind (Typ) = E_Record_Type_With_Private then
19109 -- Handle the following illegal usage:
19110 -- type Private_Type is tagged private;
19112 -- type Private_Type is new Type_Implementing_Iface;
19114 if Present (Full_View (Typ))
19115 and then Etype (Typ) /= Full_View (Typ)
19117 if Is_Interface (Etype (Typ)) then
19118 Append_Unique_Elmt (Etype (Typ), Ifaces);
19121 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19124 -- Non-private types
19127 if Is_Interface (Etype (Typ)) then
19128 Append_Unique_Elmt (Etype (Typ), Ifaces);
19131 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
19135 -- Handle entities in the list of abstract interfaces
19137 if Present (Interfaces (Typ)) then
19138 Iface_Elmt := First_Elmt (Interfaces (Typ));
19139 while Present (Iface_Elmt) loop
19140 Iface := Node (Iface_Elmt);
19142 pragma Assert (Is_Interface (Iface));
19144 if not Contain_Interface (Iface, Ifaces) then
19145 Append_Elmt (Iface, Ifaces);
19146 Collect_Implemented_Interfaces (Iface, Ifaces);
19149 Next_Elmt (Iface_Elmt);
19152 end Collect_Implemented_Interfaces;
19156 Full_Indic : Node_Id;
19157 Full_Parent : Entity_Id;
19158 Priv_Parent : Entity_Id;
19160 -- Start of processing for Process_Full_View
19163 -- First some sanity checks that must be done after semantic
19164 -- decoration of the full view and thus cannot be placed with other
19165 -- similar checks in Find_Type_Name
19167 if not Is_Limited_Type (Priv_T)
19168 and then (Is_Limited_Type (Full_T)
19169 or else Is_Limited_Composite (Full_T))
19171 if In_Instance then
19175 ("completion of nonlimited type cannot be limited", Full_T);
19176 Explain_Limited_Type (Full_T, Full_T);
19179 elsif Is_Abstract_Type (Full_T)
19180 and then not Is_Abstract_Type (Priv_T)
19183 ("completion of nonabstract type cannot be abstract", Full_T);
19185 elsif Is_Tagged_Type (Priv_T)
19186 and then Is_Limited_Type (Priv_T)
19187 and then not Is_Limited_Type (Full_T)
19189 -- If pragma CPP_Class was applied to the private declaration
19190 -- propagate the limitedness to the full-view
19192 if Is_CPP_Class (Priv_T) then
19193 Set_Is_Limited_Record (Full_T);
19195 -- GNAT allow its own definition of Limited_Controlled to disobey
19196 -- this rule in order in ease the implementation. This test is safe
19197 -- because Root_Controlled is defined in a child of System that
19198 -- normal programs are not supposed to use.
19200 elsif Is_RTE (Etype (Full_T), RE_Root_Controlled) then
19201 Set_Is_Limited_Composite (Full_T);
19204 ("completion of limited tagged type must be limited", Full_T);
19207 elsif Is_Generic_Type (Priv_T) then
19208 Error_Msg_N ("generic type cannot have a completion", Full_T);
19211 -- Check that ancestor interfaces of private and full views are
19212 -- consistent. We omit this check for synchronized types because
19213 -- they are performed on the corresponding record type when frozen.
19215 if Ada_Version >= Ada_2005
19216 and then Is_Tagged_Type (Priv_T)
19217 and then Is_Tagged_Type (Full_T)
19218 and then not Is_Concurrent_Type (Full_T)
19222 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
19223 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
19226 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
19227 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
19229 -- Ada 2005 (AI-251): The partial view shall be a descendant of
19230 -- an interface type if and only if the full type is descendant
19231 -- of the interface type (AARM 7.3 (7.3/2)).
19233 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
19235 if Present (Iface) then
19237 ("interface in partial view& not implemented by full type "
19238 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19241 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
19243 if Present (Iface) then
19245 ("interface & not implemented by partial view "
19246 & "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
19251 if Is_Tagged_Type (Priv_T)
19252 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19253 and then Is_Derived_Type (Full_T)
19255 Priv_Parent := Etype (Priv_T);
19257 -- The full view of a private extension may have been transformed
19258 -- into an unconstrained derived type declaration and a subtype
19259 -- declaration (see build_derived_record_type for details).
19261 if Nkind (N) = N_Subtype_Declaration then
19262 Full_Indic := Subtype_Indication (N);
19263 Full_Parent := Etype (Base_Type (Full_T));
19265 Full_Indic := Subtype_Indication (Type_Definition (N));
19266 Full_Parent := Etype (Full_T);
19269 -- Check that the parent type of the full type is a descendant of
19270 -- the ancestor subtype given in the private extension. If either
19271 -- entity has an Etype equal to Any_Type then we had some previous
19272 -- error situation [7.3(8)].
19274 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
19277 -- Ada 2005 (AI-251): Interfaces in the full type can be given in
19278 -- any order. Therefore we don't have to check that its parent must
19279 -- be a descendant of the parent of the private type declaration.
19281 elsif Is_Interface (Priv_Parent)
19282 and then Is_Interface (Full_Parent)
19286 -- Ada 2005 (AI-251): If the parent of the private type declaration
19287 -- is an interface there is no need to check that it is an ancestor
19288 -- of the associated full type declaration. The required tests for
19289 -- this case are performed by Build_Derived_Record_Type.
19291 elsif not Is_Interface (Base_Type (Priv_Parent))
19292 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
19295 ("parent of full type must descend from parent"
19296 & " of private extension", Full_Indic);
19298 -- First check a formal restriction, and then proceed with checking
19299 -- Ada rules. Since the formal restriction is not a serious error, we
19300 -- don't prevent further error detection for this check, hence the
19304 -- In formal mode, when completing a private extension the type
19305 -- named in the private part must be exactly the same as that
19306 -- named in the visible part.
19308 if Priv_Parent /= Full_Parent then
19309 Error_Msg_Name_1 := Chars (Priv_Parent);
19310 Check_SPARK_05_Restriction ("% expected", Full_Indic);
19313 -- Check the rules of 7.3(10): if the private extension inherits
19314 -- known discriminants, then the full type must also inherit those
19315 -- discriminants from the same (ancestor) type, and the parent
19316 -- subtype of the full type must be constrained if and only if
19317 -- the ancestor subtype of the private extension is constrained.
19319 if No (Discriminant_Specifications (Parent (Priv_T)))
19320 and then not Has_Unknown_Discriminants (Priv_T)
19321 and then Has_Discriminants (Base_Type (Priv_Parent))
19324 Priv_Indic : constant Node_Id :=
19325 Subtype_Indication (Parent (Priv_T));
19327 Priv_Constr : constant Boolean :=
19328 Is_Constrained (Priv_Parent)
19330 Nkind (Priv_Indic) = N_Subtype_Indication
19332 Is_Constrained (Entity (Priv_Indic));
19334 Full_Constr : constant Boolean :=
19335 Is_Constrained (Full_Parent)
19337 Nkind (Full_Indic) = N_Subtype_Indication
19339 Is_Constrained (Entity (Full_Indic));
19341 Priv_Discr : Entity_Id;
19342 Full_Discr : Entity_Id;
19345 Priv_Discr := First_Discriminant (Priv_Parent);
19346 Full_Discr := First_Discriminant (Full_Parent);
19347 while Present (Priv_Discr) and then Present (Full_Discr) loop
19348 if Original_Record_Component (Priv_Discr) =
19349 Original_Record_Component (Full_Discr)
19351 Corresponding_Discriminant (Priv_Discr) =
19352 Corresponding_Discriminant (Full_Discr)
19359 Next_Discriminant (Priv_Discr);
19360 Next_Discriminant (Full_Discr);
19363 if Present (Priv_Discr) or else Present (Full_Discr) then
19365 ("full view must inherit discriminants of the parent"
19366 & " type used in the private extension", Full_Indic);
19368 elsif Priv_Constr and then not Full_Constr then
19370 ("parent subtype of full type must be constrained",
19373 elsif Full_Constr and then not Priv_Constr then
19375 ("parent subtype of full type must be unconstrained",
19380 -- Check the rules of 7.3(12): if a partial view has neither
19381 -- known or unknown discriminants, then the full type
19382 -- declaration shall define a definite subtype.
19384 elsif not Has_Unknown_Discriminants (Priv_T)
19385 and then not Has_Discriminants (Priv_T)
19386 and then not Is_Constrained (Full_T)
19389 ("full view must define a constrained type if partial view"
19390 & " has no discriminants", Full_T);
19393 -- ??????? Do we implement the following properly ?????
19394 -- If the ancestor subtype of a private extension has constrained
19395 -- discriminants, then the parent subtype of the full view shall
19396 -- impose a statically matching constraint on those discriminants
19401 -- For untagged types, verify that a type without discriminants is
19402 -- not completed with an unconstrained type. A separate error message
19403 -- is produced if the full type has defaulted discriminants.
19405 if not Is_Indefinite_Subtype (Priv_T)
19406 and then Is_Indefinite_Subtype (Full_T)
19408 Error_Msg_Sloc := Sloc (Parent (Priv_T));
19410 ("full view of& not compatible with declaration#",
19413 if not Is_Tagged_Type (Full_T) then
19415 ("\one is constrained, the other unconstrained", Full_T);
19420 -- AI-419: verify that the use of "limited" is consistent
19423 Orig_Decl : constant Node_Id := Original_Node (N);
19426 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19427 and then not Limited_Present (Parent (Priv_T))
19428 and then not Synchronized_Present (Parent (Priv_T))
19429 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
19431 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
19432 and then Limited_Present (Type_Definition (Orig_Decl))
19435 ("full view of non-limited extension cannot be limited", N);
19439 -- Ada 2005 (AI-443): A synchronized private extension must be
19440 -- completed by a task or protected type.
19442 if Ada_Version >= Ada_2005
19443 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
19444 and then Synchronized_Present (Parent (Priv_T))
19445 and then not Is_Concurrent_Type (Full_T)
19447 Error_Msg_N ("full view of synchronized extension must " &
19448 "be synchronized type", N);
19451 -- Ada 2005 AI-363: if the full view has discriminants with
19452 -- defaults, it is illegal to declare constrained access subtypes
19453 -- whose designated type is the current type. This allows objects
19454 -- of the type that are declared in the heap to be unconstrained.
19456 if not Has_Unknown_Discriminants (Priv_T)
19457 and then not Has_Discriminants (Priv_T)
19458 and then Has_Discriminants (Full_T)
19460 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
19462 Set_Has_Constrained_Partial_View (Full_T);
19463 Set_Has_Constrained_Partial_View (Priv_T);
19466 -- Create a full declaration for all its subtypes recorded in
19467 -- Private_Dependents and swap them similarly to the base type. These
19468 -- are subtypes that have been define before the full declaration of
19469 -- the private type. We also swap the entry in Private_Dependents list
19470 -- so we can properly restore the private view on exit from the scope.
19473 Priv_Elmt : Elmt_Id;
19474 Priv_Scop : Entity_Id;
19479 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
19480 while Present (Priv_Elmt) loop
19481 Priv := Node (Priv_Elmt);
19482 Priv_Scop := Scope (Priv);
19484 if Ekind_In (Priv, E_Private_Subtype,
19485 E_Limited_Private_Subtype,
19486 E_Record_Subtype_With_Private)
19488 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
19489 Set_Is_Itype (Full);
19490 Set_Parent (Full, Parent (Priv));
19491 Set_Associated_Node_For_Itype (Full, N);
19493 -- Now we need to complete the private subtype, but since the
19494 -- base type has already been swapped, we must also swap the
19495 -- subtypes (and thus, reverse the arguments in the call to
19496 -- Complete_Private_Subtype). Also note that we may need to
19497 -- re-establish the scope of the private subtype.
19499 Copy_And_Swap (Priv, Full);
19501 if not In_Open_Scopes (Priv_Scop) then
19502 Push_Scope (Priv_Scop);
19505 -- Reset Priv_Scop to Empty to indicate no scope was pushed
19507 Priv_Scop := Empty;
19510 Complete_Private_Subtype (Full, Priv, Full_T, N);
19512 if Present (Priv_Scop) then
19516 Replace_Elmt (Priv_Elmt, Full);
19519 Next_Elmt (Priv_Elmt);
19523 -- If the private view was tagged, copy the new primitive operations
19524 -- from the private view to the full view.
19526 if Is_Tagged_Type (Full_T) then
19528 Disp_Typ : Entity_Id;
19529 Full_List : Elist_Id;
19531 Prim_Elmt : Elmt_Id;
19532 Priv_List : Elist_Id;
19536 L : Elist_Id) return Boolean;
19537 -- Determine whether list L contains element E
19545 L : Elist_Id) return Boolean
19547 List_Elmt : Elmt_Id;
19550 List_Elmt := First_Elmt (L);
19551 while Present (List_Elmt) loop
19552 if Node (List_Elmt) = E then
19556 Next_Elmt (List_Elmt);
19562 -- Start of processing
19565 if Is_Tagged_Type (Priv_T) then
19566 Priv_List := Primitive_Operations (Priv_T);
19567 Prim_Elmt := First_Elmt (Priv_List);
19569 -- In the case of a concurrent type completing a private tagged
19570 -- type, primitives may have been declared in between the two
19571 -- views. These subprograms need to be wrapped the same way
19572 -- entries and protected procedures are handled because they
19573 -- cannot be directly shared by the two views.
19575 if Is_Concurrent_Type (Full_T) then
19577 Conc_Typ : constant Entity_Id :=
19578 Corresponding_Record_Type (Full_T);
19579 Curr_Nod : Node_Id := Parent (Conc_Typ);
19580 Wrap_Spec : Node_Id;
19583 while Present (Prim_Elmt) loop
19584 Prim := Node (Prim_Elmt);
19586 if Comes_From_Source (Prim)
19587 and then not Is_Abstract_Subprogram (Prim)
19590 Make_Subprogram_Declaration (Sloc (Prim),
19594 Obj_Typ => Conc_Typ,
19596 Parameter_Specifications (
19599 Insert_After (Curr_Nod, Wrap_Spec);
19600 Curr_Nod := Wrap_Spec;
19602 Analyze (Wrap_Spec);
19605 Next_Elmt (Prim_Elmt);
19611 -- For non-concurrent types, transfer explicit primitives, but
19612 -- omit those inherited from the parent of the private view
19613 -- since they will be re-inherited later on.
19616 Full_List := Primitive_Operations (Full_T);
19618 while Present (Prim_Elmt) loop
19619 Prim := Node (Prim_Elmt);
19621 if Comes_From_Source (Prim)
19622 and then not Contains (Prim, Full_List)
19624 Append_Elmt (Prim, Full_List);
19627 Next_Elmt (Prim_Elmt);
19631 -- Untagged private view
19634 Full_List := Primitive_Operations (Full_T);
19636 -- In this case the partial view is untagged, so here we locate
19637 -- all of the earlier primitives that need to be treated as
19638 -- dispatching (those that appear between the two views). Note
19639 -- that these additional operations must all be new operations
19640 -- (any earlier operations that override inherited operations
19641 -- of the full view will already have been inserted in the
19642 -- primitives list, marked by Check_Operation_From_Private_View
19643 -- as dispatching. Note that implicit "/=" operators are
19644 -- excluded from being added to the primitives list since they
19645 -- shouldn't be treated as dispatching (tagged "/=" is handled
19648 Prim := Next_Entity (Full_T);
19649 while Present (Prim) and then Prim /= Priv_T loop
19650 if Ekind_In (Prim, E_Procedure, E_Function) then
19651 Disp_Typ := Find_Dispatching_Type (Prim);
19653 if Disp_Typ = Full_T
19654 and then (Chars (Prim) /= Name_Op_Ne
19655 or else Comes_From_Source (Prim))
19657 Check_Controlling_Formals (Full_T, Prim);
19659 if not Is_Dispatching_Operation (Prim) then
19660 Append_Elmt (Prim, Full_List);
19661 Set_Is_Dispatching_Operation (Prim, True);
19662 Set_DT_Position (Prim, No_Uint);
19665 elsif Is_Dispatching_Operation (Prim)
19666 and then Disp_Typ /= Full_T
19669 -- Verify that it is not otherwise controlled by a
19670 -- formal or a return value of type T.
19672 Check_Controlling_Formals (Disp_Typ, Prim);
19676 Next_Entity (Prim);
19680 -- For the tagged case, the two views can share the same primitive
19681 -- operations list and the same class-wide type. Update attributes
19682 -- of the class-wide type which depend on the full declaration.
19684 if Is_Tagged_Type (Priv_T) then
19685 Set_Direct_Primitive_Operations (Priv_T, Full_List);
19686 Set_Class_Wide_Type
19687 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
19689 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
19691 (Class_Wide_Type (Priv_T), Has_Protected (Full_T));
19696 -- Ada 2005 AI 161: Check preelaborable initialization consistency
19698 if Known_To_Have_Preelab_Init (Priv_T) then
19700 -- Case where there is a pragma Preelaborable_Initialization. We
19701 -- always allow this in predefined units, which is cheating a bit,
19702 -- but it means we don't have to struggle to meet the requirements in
19703 -- the RM for having Preelaborable Initialization. Otherwise we
19704 -- require that the type meets the RM rules. But we can't check that
19705 -- yet, because of the rule about overriding Initialize, so we simply
19706 -- set a flag that will be checked at freeze time.
19708 if not In_Predefined_Unit (Full_T) then
19709 Set_Must_Have_Preelab_Init (Full_T);
19713 -- If pragma CPP_Class was applied to the private type declaration,
19714 -- propagate it now to the full type declaration.
19716 if Is_CPP_Class (Priv_T) then
19717 Set_Is_CPP_Class (Full_T);
19718 Set_Convention (Full_T, Convention_CPP);
19720 -- Check that components of imported CPP types do not have default
19723 Check_CPP_Type_Has_No_Defaults (Full_T);
19726 -- If the private view has user specified stream attributes, then so has
19729 -- Why the test, how could these flags be already set in Full_T ???
19731 if Has_Specified_Stream_Read (Priv_T) then
19732 Set_Has_Specified_Stream_Read (Full_T);
19735 if Has_Specified_Stream_Write (Priv_T) then
19736 Set_Has_Specified_Stream_Write (Full_T);
19739 if Has_Specified_Stream_Input (Priv_T) then
19740 Set_Has_Specified_Stream_Input (Full_T);
19743 if Has_Specified_Stream_Output (Priv_T) then
19744 Set_Has_Specified_Stream_Output (Full_T);
19747 -- Propagate the attributes related to pragma Default_Initial_Condition
19748 -- from the private to the full view. Note that both flags are mutually
19751 if Has_Default_Init_Cond (Priv_T)
19752 or else Has_Inherited_Default_Init_Cond (Priv_T)
19754 Propagate_Default_Init_Cond_Attributes
19755 (From_Typ => Priv_T,
19757 Private_To_Full_View => True);
19759 -- In the case where the full view is derived from another private type,
19760 -- the attributes related to pragma Default_Initial_Condition must be
19761 -- propagated from the full to the private view to maintain consistency
19765 -- type Parent_Typ is private
19766 -- with Default_Initial_Condition ...;
19768 -- type Parent_Typ is ...;
19771 -- with Pack; use Pack;
19772 -- package Pack_2 is
19773 -- type Deriv_Typ is private; -- must inherit
19775 -- type Deriv_Typ is new Parent_Typ; -- must inherit
19778 elsif Has_Default_Init_Cond (Full_T)
19779 or else Has_Inherited_Default_Init_Cond (Full_T)
19781 Propagate_Default_Init_Cond_Attributes
19782 (From_Typ => Full_T,
19784 Private_To_Full_View => True);
19787 -- Propagate the attributes related to pragma Ghost from the private to
19790 if Is_Ghost_Entity (Priv_T) then
19791 Set_Is_Ghost_Entity (Full_T);
19793 -- The Ghost policy in effect at the point of declaration and at the
19794 -- point of completion must match (SPARK RM 6.9(15)).
19796 Check_Ghost_Completion (Priv_T, Full_T);
19798 -- In the case where the private view of a tagged type lacks a parent
19799 -- type and is subject to pragma Ghost, ensure that the parent type
19800 -- specified by the full view is also Ghost (SPARK RM 6.9(9)).
19802 if Is_Derived_Type (Full_T) then
19803 Check_Ghost_Derivation (Full_T);
19807 -- Propagate invariants to full type
19809 if Has_Invariants (Priv_T) then
19810 Set_Has_Invariants (Full_T);
19811 Set_Invariant_Procedure (Full_T, Invariant_Procedure (Priv_T));
19814 if Has_Inheritable_Invariants (Priv_T) then
19815 Set_Has_Inheritable_Invariants (Full_T);
19818 -- Propagate predicates to full type, and predicate function if already
19819 -- defined. It is not clear that this can actually happen? the partial
19820 -- view cannot be frozen yet, and the predicate function has not been
19821 -- built. Still it is a cheap check and seems safer to make it.
19823 if Has_Predicates (Priv_T) then
19824 if Present (Predicate_Function (Priv_T)) then
19825 Set_Predicate_Function (Full_T, Predicate_Function (Priv_T));
19828 Set_Has_Predicates (Full_T);
19830 end Process_Full_View;
19832 -----------------------------------
19833 -- Process_Incomplete_Dependents --
19834 -----------------------------------
19836 procedure Process_Incomplete_Dependents
19838 Full_T : Entity_Id;
19841 Inc_Elmt : Elmt_Id;
19842 Priv_Dep : Entity_Id;
19843 New_Subt : Entity_Id;
19845 Disc_Constraint : Elist_Id;
19848 if No (Private_Dependents (Inc_T)) then
19852 -- Itypes that may be generated by the completion of an incomplete
19853 -- subtype are not used by the back-end and not attached to the tree.
19854 -- They are created only for constraint-checking purposes.
19856 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
19857 while Present (Inc_Elmt) loop
19858 Priv_Dep := Node (Inc_Elmt);
19860 if Ekind (Priv_Dep) = E_Subprogram_Type then
19862 -- An Access_To_Subprogram type may have a return type or a
19863 -- parameter type that is incomplete. Replace with the full view.
19865 if Etype (Priv_Dep) = Inc_T then
19866 Set_Etype (Priv_Dep, Full_T);
19870 Formal : Entity_Id;
19873 Formal := First_Formal (Priv_Dep);
19874 while Present (Formal) loop
19875 if Etype (Formal) = Inc_T then
19876 Set_Etype (Formal, Full_T);
19879 Next_Formal (Formal);
19883 elsif Is_Overloadable (Priv_Dep) then
19885 -- If a subprogram in the incomplete dependents list is primitive
19886 -- for a tagged full type then mark it as a dispatching operation,
19887 -- check whether it overrides an inherited subprogram, and check
19888 -- restrictions on its controlling formals. Note that a protected
19889 -- operation is never dispatching: only its wrapper operation
19890 -- (which has convention Ada) is.
19892 if Is_Tagged_Type (Full_T)
19893 and then Is_Primitive (Priv_Dep)
19894 and then Convention (Priv_Dep) /= Convention_Protected
19896 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
19897 Set_Is_Dispatching_Operation (Priv_Dep);
19898 Check_Controlling_Formals (Full_T, Priv_Dep);
19901 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
19903 -- Can happen during processing of a body before the completion
19904 -- of a TA type. Ignore, because spec is also on dependent list.
19908 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
19909 -- corresponding subtype of the full view.
19911 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
19912 Set_Subtype_Indication
19913 (Parent (Priv_Dep), New_Occurrence_Of (Full_T, Sloc (Priv_Dep)));
19914 Set_Etype (Priv_Dep, Full_T);
19915 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
19916 Set_Analyzed (Parent (Priv_Dep), False);
19918 -- Reanalyze the declaration, suppressing the call to
19919 -- Enter_Name to avoid duplicate names.
19921 Analyze_Subtype_Declaration
19922 (N => Parent (Priv_Dep),
19925 -- Dependent is a subtype
19928 -- We build a new subtype indication using the full view of the
19929 -- incomplete parent. The discriminant constraints have been
19930 -- elaborated already at the point of the subtype declaration.
19932 New_Subt := Create_Itype (E_Void, N);
19934 if Has_Discriminants (Full_T) then
19935 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
19937 Disc_Constraint := No_Elist;
19940 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
19941 Set_Full_View (Priv_Dep, New_Subt);
19944 Next_Elmt (Inc_Elmt);
19946 end Process_Incomplete_Dependents;
19948 --------------------------------
19949 -- Process_Range_Expr_In_Decl --
19950 --------------------------------
19952 procedure Process_Range_Expr_In_Decl
19955 Subtyp : Entity_Id := Empty;
19956 Check_List : List_Id := Empty_List;
19957 R_Check_Off : Boolean := False;
19958 In_Iter_Schm : Boolean := False)
19961 R_Checks : Check_Result;
19962 Insert_Node : Node_Id;
19963 Def_Id : Entity_Id;
19966 Analyze_And_Resolve (R, Base_Type (T));
19968 if Nkind (R) = N_Range then
19970 -- In SPARK, all ranges should be static, with the exception of the
19971 -- discrete type definition of a loop parameter specification.
19973 if not In_Iter_Schm
19974 and then not Is_OK_Static_Range (R)
19976 Check_SPARK_05_Restriction ("range should be static", R);
19979 Lo := Low_Bound (R);
19980 Hi := High_Bound (R);
19982 -- Validity checks on the range of a quantified expression are
19983 -- delayed until the construct is transformed into a loop.
19985 if Nkind (Parent (R)) = N_Loop_Parameter_Specification
19986 and then Nkind (Parent (Parent (R))) = N_Quantified_Expression
19990 -- We need to ensure validity of the bounds here, because if we
19991 -- go ahead and do the expansion, then the expanded code will get
19992 -- analyzed with range checks suppressed and we miss the check.
19994 -- WARNING: The capture of the range bounds with xxx_FIRST/_LAST and
19995 -- the temporaries generated by routine Remove_Side_Effects by means
19996 -- of validity checks must use the same names. When a range appears
19997 -- in the parent of a generic, the range is processed with checks
19998 -- disabled as part of the generic context and with checks enabled
19999 -- for code generation purposes. This leads to link issues as the
20000 -- generic contains references to xxx_FIRST/_LAST, but the inlined
20001 -- template sees the temporaries generated by Remove_Side_Effects.
20004 Validity_Check_Range (R, Subtyp);
20007 -- If there were errors in the declaration, try and patch up some
20008 -- common mistakes in the bounds. The cases handled are literals
20009 -- which are Integer where the expected type is Real and vice versa.
20010 -- These corrections allow the compilation process to proceed further
20011 -- along since some basic assumptions of the format of the bounds
20014 if Etype (R) = Any_Type then
20015 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
20017 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
20019 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
20021 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
20023 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
20025 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
20027 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
20029 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
20036 -- If the bounds of the range have been mistakenly given as string
20037 -- literals (perhaps in place of character literals), then an error
20038 -- has already been reported, but we rewrite the string literal as a
20039 -- bound of the range's type to avoid blowups in later processing
20040 -- that looks at static values.
20042 if Nkind (Lo) = N_String_Literal then
20044 Make_Attribute_Reference (Sloc (Lo),
20045 Prefix => New_Occurrence_Of (T, Sloc (Lo)),
20046 Attribute_Name => Name_First));
20047 Analyze_And_Resolve (Lo);
20050 if Nkind (Hi) = N_String_Literal then
20052 Make_Attribute_Reference (Sloc (Hi),
20053 Prefix => New_Occurrence_Of (T, Sloc (Hi)),
20054 Attribute_Name => Name_First));
20055 Analyze_And_Resolve (Hi);
20058 -- If bounds aren't scalar at this point then exit, avoiding
20059 -- problems with further processing of the range in this procedure.
20061 if not Is_Scalar_Type (Etype (Lo)) then
20065 -- Resolve (actually Sem_Eval) has checked that the bounds are in
20066 -- then range of the base type. Here we check whether the bounds
20067 -- are in the range of the subtype itself. Note that if the bounds
20068 -- represent the null range the Constraint_Error exception should
20071 -- ??? The following code should be cleaned up as follows
20073 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
20074 -- is done in the call to Range_Check (R, T); below
20076 -- 2. The use of R_Check_Off should be investigated and possibly
20077 -- removed, this would clean up things a bit.
20079 if Is_Null_Range (Lo, Hi) then
20083 -- Capture values of bounds and generate temporaries for them
20084 -- if needed, before applying checks, since checks may cause
20085 -- duplication of the expression without forcing evaluation.
20087 -- The forced evaluation removes side effects from expressions,
20088 -- which should occur also in GNATprove mode. Otherwise, we end up
20089 -- with unexpected insertions of actions at places where this is
20090 -- not supposed to occur, e.g. on default parameters of a call.
20092 if Expander_Active or GNATprove_Mode then
20094 -- If no subtype name, then just call Force_Evaluation to
20095 -- create declarations as needed to deal with side effects.
20096 -- Also ignore calls from within a record type, where we
20097 -- have possible scoping issues.
20099 if No (Subtyp) or else Is_Record_Type (Current_Scope) then
20100 Force_Evaluation (Lo);
20101 Force_Evaluation (Hi);
20103 -- If a subtype is given, then we capture the bounds if they
20104 -- are not known at compile time, using constant identifiers
20105 -- xxx_FIRST and xxx_LAST where xxx is the name of the subtype.
20107 -- Note: we do this transformation even if expansion is not
20108 -- active, and in particular we do it in GNATprove_Mode since
20109 -- the transformation is in general required to ensure that the
20110 -- resulting tree has proper Ada semantics.
20112 -- Historical note: We used to just do Force_Evaluation calls
20113 -- in all cases, but it is better to capture the bounds with
20114 -- proper non-serialized names, since these will be accessed
20115 -- from other units, and hence may be public, and also we can
20116 -- then expand 'First and 'Last references to be references to
20117 -- these special names.
20120 if not Compile_Time_Known_Value (Lo)
20122 -- No need to capture bounds if they already are
20123 -- references to constants.
20125 and then not (Is_Entity_Name (Lo)
20126 and then Is_Constant_Object (Entity (Lo)))
20129 Loc : constant Source_Ptr := Sloc (Lo);
20130 Lov : constant Entity_Id :=
20131 Make_Defining_Identifier (Loc,
20133 New_External_Name (Chars (Subtyp), "_FIRST"));
20136 Make_Object_Declaration (Loc,
20137 Defining_Identifier => Lov,
20138 Object_Definition =>
20139 New_Occurrence_Of (Base_Type (T), Loc),
20140 Constant_Present => True,
20141 Expression => Relocate_Node (Lo)));
20142 Rewrite (Lo, New_Occurrence_Of (Lov, Loc));
20146 if not Compile_Time_Known_Value (Hi)
20147 and then not (Is_Entity_Name (Hi)
20148 and then Is_Constant_Object (Entity (Hi)))
20151 Loc : constant Source_Ptr := Sloc (Hi);
20152 Hiv : constant Entity_Id :=
20153 Make_Defining_Identifier (Loc,
20155 New_External_Name (Chars (Subtyp), "_LAST"));
20158 Make_Object_Declaration (Loc,
20159 Defining_Identifier => Hiv,
20160 Object_Definition =>
20161 New_Occurrence_Of (Base_Type (T), Loc),
20162 Constant_Present => True,
20163 Expression => Relocate_Node (Hi)));
20164 Rewrite (Hi, New_Occurrence_Of (Hiv, Loc));
20170 -- We use a flag here instead of suppressing checks on the
20171 -- type because the type we check against isn't necessarily
20172 -- the place where we put the check.
20174 if not R_Check_Off then
20175 R_Checks := Get_Range_Checks (R, T);
20177 -- Look up tree to find an appropriate insertion point. We
20178 -- can't just use insert_actions because later processing
20179 -- depends on the insertion node. Prior to Ada 2012 the
20180 -- insertion point could only be a declaration or a loop, but
20181 -- quantified expressions can appear within any context in an
20182 -- expression, and the insertion point can be any statement,
20183 -- pragma, or declaration.
20185 Insert_Node := Parent (R);
20186 while Present (Insert_Node) loop
20188 Nkind (Insert_Node) in N_Declaration
20191 (Insert_Node, N_Component_Declaration,
20192 N_Loop_Parameter_Specification,
20193 N_Function_Specification,
20194 N_Procedure_Specification);
20196 exit when Nkind (Insert_Node) in N_Later_Decl_Item
20197 or else Nkind (Insert_Node) in
20198 N_Statement_Other_Than_Procedure_Call
20199 or else Nkind_In (Insert_Node, N_Procedure_Call_Statement,
20202 Insert_Node := Parent (Insert_Node);
20205 -- Why would Type_Decl not be present??? Without this test,
20206 -- short regression tests fail.
20208 if Present (Insert_Node) then
20210 -- Case of loop statement. Verify that the range is part
20211 -- of the subtype indication of the iteration scheme.
20213 if Nkind (Insert_Node) = N_Loop_Statement then
20218 Indic := Parent (R);
20219 while Present (Indic)
20220 and then Nkind (Indic) /= N_Subtype_Indication
20222 Indic := Parent (Indic);
20225 if Present (Indic) then
20226 Def_Id := Etype (Subtype_Mark (Indic));
20228 Insert_Range_Checks
20232 Sloc (Insert_Node),
20234 Do_Before => True);
20238 -- Insertion before a declaration. If the declaration
20239 -- includes discriminants, the list of applicable checks
20240 -- is given by the caller.
20242 elsif Nkind (Insert_Node) in N_Declaration then
20243 Def_Id := Defining_Identifier (Insert_Node);
20245 if (Ekind (Def_Id) = E_Record_Type
20246 and then Depends_On_Discriminant (R))
20248 (Ekind (Def_Id) = E_Protected_Type
20249 and then Has_Discriminants (Def_Id))
20251 Append_Range_Checks
20253 Check_List, Def_Id, Sloc (Insert_Node), R);
20256 Insert_Range_Checks
20258 Insert_Node, Def_Id, Sloc (Insert_Node), R);
20262 -- Insertion before a statement. Range appears in the
20263 -- context of a quantified expression. Insertion will
20264 -- take place when expression is expanded.
20273 -- Case of other than an explicit N_Range node
20275 -- The forced evaluation removes side effects from expressions, which
20276 -- should occur also in GNATprove mode. Otherwise, we end up with
20277 -- unexpected insertions of actions at places where this is not
20278 -- supposed to occur, e.g. on default parameters of a call.
20280 elsif Expander_Active or GNATprove_Mode then
20281 Get_Index_Bounds (R, Lo, Hi);
20282 Force_Evaluation (Lo);
20283 Force_Evaluation (Hi);
20285 end Process_Range_Expr_In_Decl;
20287 --------------------------------------
20288 -- Process_Real_Range_Specification --
20289 --------------------------------------
20291 procedure Process_Real_Range_Specification (Def : Node_Id) is
20292 Spec : constant Node_Id := Real_Range_Specification (Def);
20295 Err : Boolean := False;
20297 procedure Analyze_Bound (N : Node_Id);
20298 -- Analyze and check one bound
20300 -------------------
20301 -- Analyze_Bound --
20302 -------------------
20304 procedure Analyze_Bound (N : Node_Id) is
20306 Analyze_And_Resolve (N, Any_Real);
20308 if not Is_OK_Static_Expression (N) then
20309 Flag_Non_Static_Expr
20310 ("bound in real type definition is not static!", N);
20315 -- Start of processing for Process_Real_Range_Specification
20318 if Present (Spec) then
20319 Lo := Low_Bound (Spec);
20320 Hi := High_Bound (Spec);
20321 Analyze_Bound (Lo);
20322 Analyze_Bound (Hi);
20324 -- If error, clear away junk range specification
20327 Set_Real_Range_Specification (Def, Empty);
20330 end Process_Real_Range_Specification;
20332 ---------------------
20333 -- Process_Subtype --
20334 ---------------------
20336 function Process_Subtype
20338 Related_Nod : Node_Id;
20339 Related_Id : Entity_Id := Empty;
20340 Suffix : Character := ' ') return Entity_Id
20343 Def_Id : Entity_Id;
20344 Error_Node : Node_Id;
20345 Full_View_Id : Entity_Id;
20346 Subtype_Mark_Id : Entity_Id;
20348 May_Have_Null_Exclusion : Boolean;
20350 procedure Check_Incomplete (T : Entity_Id);
20351 -- Called to verify that an incomplete type is not used prematurely
20353 ----------------------
20354 -- Check_Incomplete --
20355 ----------------------
20357 procedure Check_Incomplete (T : Entity_Id) is
20359 -- Ada 2005 (AI-412): Incomplete subtypes are legal
20361 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
20363 not (Ada_Version >= Ada_2005
20365 (Nkind (Parent (T)) = N_Subtype_Declaration
20366 or else (Nkind (Parent (T)) = N_Subtype_Indication
20367 and then Nkind (Parent (Parent (T))) =
20368 N_Subtype_Declaration)))
20370 Error_Msg_N ("invalid use of type before its full declaration", T);
20372 end Check_Incomplete;
20374 -- Start of processing for Process_Subtype
20377 -- Case of no constraints present
20379 if Nkind (S) /= N_Subtype_Indication then
20381 Check_Incomplete (S);
20384 -- Ada 2005 (AI-231): Static check
20386 if Ada_Version >= Ada_2005
20387 and then Present (P)
20388 and then Null_Exclusion_Present (P)
20389 and then Nkind (P) /= N_Access_To_Object_Definition
20390 and then not Is_Access_Type (Entity (S))
20392 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
20395 -- The following is ugly, can't we have a range or even a flag???
20397 May_Have_Null_Exclusion :=
20398 Nkind_In (P, N_Access_Definition,
20399 N_Access_Function_Definition,
20400 N_Access_Procedure_Definition,
20401 N_Access_To_Object_Definition,
20403 N_Component_Definition)
20405 Nkind_In (P, N_Derived_Type_Definition,
20406 N_Discriminant_Specification,
20407 N_Formal_Object_Declaration,
20408 N_Object_Declaration,
20409 N_Object_Renaming_Declaration,
20410 N_Parameter_Specification,
20411 N_Subtype_Declaration);
20413 -- Create an Itype that is a duplicate of Entity (S) but with the
20414 -- null-exclusion attribute.
20416 if May_Have_Null_Exclusion
20417 and then Is_Access_Type (Entity (S))
20418 and then Null_Exclusion_Present (P)
20420 -- No need to check the case of an access to object definition.
20421 -- It is correct to define double not-null pointers.
20424 -- type Not_Null_Int_Ptr is not null access Integer;
20425 -- type Acc is not null access Not_Null_Int_Ptr;
20427 and then Nkind (P) /= N_Access_To_Object_Definition
20429 if Can_Never_Be_Null (Entity (S)) then
20430 case Nkind (Related_Nod) is
20431 when N_Full_Type_Declaration =>
20432 if Nkind (Type_Definition (Related_Nod))
20433 in N_Array_Type_Definition
20437 (Component_Definition
20438 (Type_Definition (Related_Nod)));
20441 Subtype_Indication (Type_Definition (Related_Nod));
20444 when N_Subtype_Declaration =>
20445 Error_Node := Subtype_Indication (Related_Nod);
20447 when N_Object_Declaration =>
20448 Error_Node := Object_Definition (Related_Nod);
20450 when N_Component_Declaration =>
20452 Subtype_Indication (Component_Definition (Related_Nod));
20454 when N_Allocator =>
20455 Error_Node := Expression (Related_Nod);
20458 pragma Assert (False);
20459 Error_Node := Related_Nod;
20463 ("`NOT NULL` not allowed (& already excludes null)",
20469 Create_Null_Excluding_Itype
20471 Related_Nod => P));
20472 Set_Entity (S, Etype (S));
20477 -- Case of constraint present, so that we have an N_Subtype_Indication
20478 -- node (this node is created only if constraints are present).
20481 Find_Type (Subtype_Mark (S));
20483 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
20485 (Nkind (Parent (S)) = N_Subtype_Declaration
20486 and then Is_Itype (Defining_Identifier (Parent (S))))
20488 Check_Incomplete (Subtype_Mark (S));
20492 Subtype_Mark_Id := Entity (Subtype_Mark (S));
20494 -- Explicit subtype declaration case
20496 if Nkind (P) = N_Subtype_Declaration then
20497 Def_Id := Defining_Identifier (P);
20499 -- Explicit derived type definition case
20501 elsif Nkind (P) = N_Derived_Type_Definition then
20502 Def_Id := Defining_Identifier (Parent (P));
20504 -- Implicit case, the Def_Id must be created as an implicit type.
20505 -- The one exception arises in the case of concurrent types, array
20506 -- and access types, where other subsidiary implicit types may be
20507 -- created and must appear before the main implicit type. In these
20508 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
20509 -- has not yet been called to create Def_Id.
20512 if Is_Array_Type (Subtype_Mark_Id)
20513 or else Is_Concurrent_Type (Subtype_Mark_Id)
20514 or else Is_Access_Type (Subtype_Mark_Id)
20518 -- For the other cases, we create a new unattached Itype,
20519 -- and set the indication to ensure it gets attached later.
20523 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20527 -- If the kind of constraint is invalid for this kind of type,
20528 -- then give an error, and then pretend no constraint was given.
20530 if not Is_Valid_Constraint_Kind
20531 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
20534 ("incorrect constraint for this kind of type", Constraint (S));
20536 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
20538 -- Set Ekind of orphan itype, to prevent cascaded errors
20540 if Present (Def_Id) then
20541 Set_Ekind (Def_Id, Ekind (Any_Type));
20544 -- Make recursive call, having got rid of the bogus constraint
20546 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
20549 -- Remaining processing depends on type. Select on Base_Type kind to
20550 -- ensure getting to the concrete type kind in the case of a private
20551 -- subtype (needed when only doing semantic analysis).
20553 case Ekind (Base_Type (Subtype_Mark_Id)) is
20554 when Access_Kind =>
20556 -- If this is a constraint on a class-wide type, discard it.
20557 -- There is currently no way to express a partial discriminant
20558 -- constraint on a type with unknown discriminants. This is
20559 -- a pathology that the ACATS wisely decides not to test.
20561 if Is_Class_Wide_Type (Designated_Type (Subtype_Mark_Id)) then
20562 if Comes_From_Source (S) then
20564 ("constraint on class-wide type ignored??",
20568 if Nkind (P) = N_Subtype_Declaration then
20569 Set_Subtype_Indication (P,
20570 New_Occurrence_Of (Subtype_Mark_Id, Sloc (S)));
20573 return Subtype_Mark_Id;
20576 Constrain_Access (Def_Id, S, Related_Nod);
20579 and then Is_Itype (Designated_Type (Def_Id))
20580 and then Nkind (Related_Nod) = N_Subtype_Declaration
20581 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
20583 Build_Itype_Reference
20584 (Designated_Type (Def_Id), Related_Nod);
20588 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
20590 when Decimal_Fixed_Point_Kind =>
20591 Constrain_Decimal (Def_Id, S);
20593 when Enumeration_Kind =>
20594 Constrain_Enumeration (Def_Id, S);
20595 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20597 when Ordinary_Fixed_Point_Kind =>
20598 Constrain_Ordinary_Fixed (Def_Id, S);
20601 Constrain_Float (Def_Id, S);
20603 when Integer_Kind =>
20604 Constrain_Integer (Def_Id, S);
20605 Inherit_Predicate_Flags (Def_Id, Subtype_Mark_Id);
20607 when E_Record_Type |
20610 E_Incomplete_Type =>
20611 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20613 if Ekind (Def_Id) = E_Incomplete_Type then
20614 Set_Private_Dependents (Def_Id, New_Elmt_List);
20617 when Private_Kind =>
20618 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
20619 Set_Private_Dependents (Def_Id, New_Elmt_List);
20621 -- In case of an invalid constraint prevent further processing
20622 -- since the type constructed is missing expected fields.
20624 if Etype (Def_Id) = Any_Type then
20628 -- If the full view is that of a task with discriminants,
20629 -- we must constrain both the concurrent type and its
20630 -- corresponding record type. Otherwise we will just propagate
20631 -- the constraint to the full view, if available.
20633 if Present (Full_View (Subtype_Mark_Id))
20634 and then Has_Discriminants (Subtype_Mark_Id)
20635 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
20638 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
20640 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
20641 Constrain_Concurrent (Full_View_Id, S,
20642 Related_Nod, Related_Id, Suffix);
20643 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
20644 Set_Full_View (Def_Id, Full_View_Id);
20646 -- Introduce an explicit reference to the private subtype,
20647 -- to prevent scope anomalies in gigi if first use appears
20648 -- in a nested context, e.g. a later function body.
20649 -- Should this be generated in other contexts than a full
20650 -- type declaration?
20652 if Is_Itype (Def_Id)
20654 Nkind (Parent (P)) = N_Full_Type_Declaration
20656 Build_Itype_Reference (Def_Id, Parent (P));
20660 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
20663 when Concurrent_Kind =>
20664 Constrain_Concurrent (Def_Id, S,
20665 Related_Nod, Related_Id, Suffix);
20668 Error_Msg_N ("invalid subtype mark in subtype indication", S);
20671 -- Size and Convention are always inherited from the base type
20673 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
20674 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
20678 end Process_Subtype;
20680 --------------------------------------------
20681 -- Propagate_Default_Init_Cond_Attributes --
20682 --------------------------------------------
20684 procedure Propagate_Default_Init_Cond_Attributes
20685 (From_Typ : Entity_Id;
20686 To_Typ : Entity_Id;
20687 Parent_To_Derivation : Boolean := False;
20688 Private_To_Full_View : Boolean := False)
20690 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id);
20691 -- Remove the default initial procedure (if any) from the rep chain of
20694 ----------------------------------------
20695 -- Remove_Default_Init_Cond_Procedure --
20696 ----------------------------------------
20698 procedure Remove_Default_Init_Cond_Procedure (Typ : Entity_Id) is
20699 Found : Boolean := False;
20705 Subp := Subprograms_For_Type (Typ);
20706 while Present (Subp) loop
20707 if Is_Default_Init_Cond_Procedure (Subp) then
20713 Subp := Subprograms_For_Type (Subp);
20717 Set_Subprograms_For_Type (Prev, Subprograms_For_Type (Subp));
20718 Set_Subprograms_For_Type (Subp, Empty);
20720 end Remove_Default_Init_Cond_Procedure;
20724 Inherit_Procedure : Boolean := False;
20726 -- Start of processing for Propagate_Default_Init_Cond_Attributes
20729 if Has_Default_Init_Cond (From_Typ) then
20731 -- A derived type inherits the attributes from its parent type
20733 if Parent_To_Derivation then
20734 Set_Has_Inherited_Default_Init_Cond (To_Typ);
20736 -- A full view shares the attributes with its private view
20739 Set_Has_Default_Init_Cond (To_Typ);
20742 Inherit_Procedure := True;
20744 -- Due to the order of expansion, a derived private type is processed
20745 -- by two routines which both attempt to set the attributes related
20746 -- to pragma Default_Initial_Condition - Build_Derived_Type and then
20747 -- Process_Full_View.
20750 -- type Parent_Typ is private
20751 -- with Default_Initial_Condition ...;
20753 -- type Parent_Typ is ...;
20756 -- with Pack; use Pack;
20757 -- package Pack_2 is
20758 -- type Deriv_Typ is private
20759 -- with Default_Initial_Condition ...;
20761 -- type Deriv_Typ is new Parent_Typ;
20764 -- When Build_Derived_Type operates, it sets the attributes on the
20765 -- full view without taking into account that the private view may
20766 -- define its own default initial condition procedure. This becomes
20767 -- apparent in Process_Full_View which must undo some of the work by
20768 -- Build_Derived_Type and propagate the attributes from the private
20769 -- to the full view.
20771 if Private_To_Full_View then
20772 Set_Has_Inherited_Default_Init_Cond (To_Typ, False);
20773 Remove_Default_Init_Cond_Procedure (To_Typ);
20776 -- A type must inherit the default initial condition procedure from a
20777 -- parent type when the parent itself is inheriting the procedure or
20778 -- when it is defining one. This circuitry is also used when dealing
20779 -- with the private / full view of a type.
20781 elsif Has_Inherited_Default_Init_Cond (From_Typ)
20782 or (Parent_To_Derivation
20783 and Present (Get_Pragma
20784 (From_Typ, Pragma_Default_Initial_Condition)))
20786 Set_Has_Inherited_Default_Init_Cond (To_Typ);
20787 Inherit_Procedure := True;
20790 if Inherit_Procedure
20791 and then No (Default_Init_Cond_Procedure (To_Typ))
20793 Set_Default_Init_Cond_Procedure
20794 (To_Typ, Default_Init_Cond_Procedure (From_Typ));
20796 end Propagate_Default_Init_Cond_Attributes;
20798 -----------------------------
20799 -- Record_Type_Declaration --
20800 -----------------------------
20802 procedure Record_Type_Declaration
20807 Def : constant Node_Id := Type_Definition (N);
20808 Is_Tagged : Boolean;
20809 Tag_Comp : Entity_Id;
20812 -- These flags must be initialized before calling Process_Discriminants
20813 -- because this routine makes use of them.
20815 Set_Ekind (T, E_Record_Type);
20817 Init_Size_Align (T);
20818 Set_Interfaces (T, No_Elist);
20819 Set_Stored_Constraint (T, No_Elist);
20820 Set_Default_SSO (T);
20824 if Ada_Version < Ada_2005 or else not Interface_Present (Def) then
20825 if Limited_Present (Def) then
20826 Check_SPARK_05_Restriction ("limited is not allowed", N);
20829 if Abstract_Present (Def) then
20830 Check_SPARK_05_Restriction ("abstract is not allowed", N);
20833 -- The flag Is_Tagged_Type might have already been set by
20834 -- Find_Type_Name if it detected an error for declaration T. This
20835 -- arises in the case of private tagged types where the full view
20836 -- omits the word tagged.
20839 Tagged_Present (Def)
20840 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
20842 Set_Is_Limited_Record (T, Limited_Present (Def));
20845 Set_Is_Tagged_Type (T, True);
20846 Set_No_Tagged_Streams_Pragma (T, No_Tagged_Streams);
20849 -- Type is abstract if full declaration carries keyword, or if
20850 -- previous partial view did.
20852 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
20853 or else Abstract_Present (Def));
20856 Check_SPARK_05_Restriction ("interface is not allowed", N);
20859 Analyze_Interface_Declaration (T, Def);
20861 if Present (Discriminant_Specifications (N)) then
20863 ("interface types cannot have discriminants",
20864 Defining_Identifier
20865 (First (Discriminant_Specifications (N))));
20869 -- First pass: if there are self-referential access components,
20870 -- create the required anonymous access type declarations, and if
20871 -- need be an incomplete type declaration for T itself.
20873 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
20875 if Ada_Version >= Ada_2005
20876 and then Present (Interface_List (Def))
20878 Check_Interfaces (N, Def);
20881 Ifaces_List : Elist_Id;
20884 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
20885 -- already in the parents.
20889 Ifaces_List => Ifaces_List,
20890 Exclude_Parents => True);
20892 Set_Interfaces (T, Ifaces_List);
20896 -- Records constitute a scope for the component declarations within.
20897 -- The scope is created prior to the processing of these declarations.
20898 -- Discriminants are processed first, so that they are visible when
20899 -- processing the other components. The Ekind of the record type itself
20900 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
20902 -- Enter record scope
20906 -- If an incomplete or private type declaration was already given for
20907 -- the type, then this scope already exists, and the discriminants have
20908 -- been declared within. We must verify that the full declaration
20909 -- matches the incomplete one.
20911 Check_Or_Process_Discriminants (N, T, Prev);
20913 Set_Is_Constrained (T, not Has_Discriminants (T));
20914 Set_Has_Delayed_Freeze (T, True);
20916 -- For tagged types add a manually analyzed component corresponding
20917 -- to the component _tag, the corresponding piece of tree will be
20918 -- expanded as part of the freezing actions if it is not a CPP_Class.
20922 -- Do not add the tag unless we are in expansion mode
20924 if Expander_Active then
20925 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
20926 Enter_Name (Tag_Comp);
20928 Set_Ekind (Tag_Comp, E_Component);
20929 Set_Is_Tag (Tag_Comp);
20930 Set_Is_Aliased (Tag_Comp);
20931 Set_Etype (Tag_Comp, RTE (RE_Tag));
20932 Set_DT_Entry_Count (Tag_Comp, No_Uint);
20933 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
20934 Init_Component_Location (Tag_Comp);
20936 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
20937 -- implemented interfaces.
20939 if Has_Interfaces (T) then
20940 Add_Interface_Tag_Components (N, T);
20944 Make_Class_Wide_Type (T);
20945 Set_Direct_Primitive_Operations (T, New_Elmt_List);
20948 -- We must suppress range checks when processing record components in
20949 -- the presence of discriminants, since we don't want spurious checks to
20950 -- be generated during their analysis, but Suppress_Range_Checks flags
20951 -- must be reset the after processing the record definition.
20953 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
20954 -- couldn't we just use the normal range check suppression method here.
20955 -- That would seem cleaner ???
20957 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
20958 Set_Kill_Range_Checks (T, True);
20959 Record_Type_Definition (Def, Prev);
20960 Set_Kill_Range_Checks (T, False);
20962 Record_Type_Definition (Def, Prev);
20965 -- Exit from record scope
20969 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
20970 -- the implemented interfaces and associate them an aliased entity.
20973 and then not Is_Empty_List (Interface_List (Def))
20975 Derive_Progenitor_Subprograms (T, T);
20978 Check_Function_Writable_Actuals (N);
20979 end Record_Type_Declaration;
20981 ----------------------------
20982 -- Record_Type_Definition --
20983 ----------------------------
20985 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
20986 Component : Entity_Id;
20987 Ctrl_Components : Boolean := False;
20988 Final_Storage_Only : Boolean;
20992 if Ekind (Prev_T) = E_Incomplete_Type then
20993 T := Full_View (Prev_T);
20998 -- In SPARK, tagged types and type extensions may only be declared in
20999 -- the specification of library unit packages.
21001 if Present (Def) and then Is_Tagged_Type (T) then
21007 if Nkind (Parent (Def)) = N_Full_Type_Declaration then
21008 Typ := Parent (Def);
21011 (Nkind (Parent (Def)) = N_Derived_Type_Definition);
21012 Typ := Parent (Parent (Def));
21015 Ctxt := Parent (Typ);
21017 if Nkind (Ctxt) = N_Package_Body
21018 and then Nkind (Parent (Ctxt)) = N_Compilation_Unit
21020 Check_SPARK_05_Restriction
21021 ("type should be defined in package specification", Typ);
21023 elsif Nkind (Ctxt) /= N_Package_Specification
21024 or else Nkind (Parent (Parent (Ctxt))) /= N_Compilation_Unit
21026 Check_SPARK_05_Restriction
21027 ("type should be defined in library unit package", Typ);
21032 Final_Storage_Only := not Is_Controlled (T);
21034 -- Ada 2005: Check whether an explicit Limited is present in a derived
21035 -- type declaration.
21037 if Nkind (Parent (Def)) = N_Derived_Type_Definition
21038 and then Limited_Present (Parent (Def))
21040 Set_Is_Limited_Record (T);
21043 -- If the component list of a record type is defined by the reserved
21044 -- word null and there is no discriminant part, then the record type has
21045 -- no components and all records of the type are null records (RM 3.7)
21046 -- This procedure is also called to process the extension part of a
21047 -- record extension, in which case the current scope may have inherited
21051 or else No (Component_List (Def))
21052 or else Null_Present (Component_List (Def))
21054 if not Is_Tagged_Type (T) then
21055 Check_SPARK_05_Restriction ("untagged record cannot be null", Def);
21059 Analyze_Declarations (Component_Items (Component_List (Def)));
21061 if Present (Variant_Part (Component_List (Def))) then
21062 Check_SPARK_05_Restriction ("variant part is not allowed", Def);
21063 Analyze (Variant_Part (Component_List (Def)));
21067 -- After completing the semantic analysis of the record definition,
21068 -- record components, both new and inherited, are accessible. Set their
21069 -- kind accordingly. Exclude malformed itypes from illegal declarations,
21070 -- whose Ekind may be void.
21072 Component := First_Entity (Current_Scope);
21073 while Present (Component) loop
21074 if Ekind (Component) = E_Void
21075 and then not Is_Itype (Component)
21077 Set_Ekind (Component, E_Component);
21078 Init_Component_Location (Component);
21081 if Has_Task (Etype (Component)) then
21085 if Has_Protected (Etype (Component)) then
21086 Set_Has_Protected (T);
21089 if Ekind (Component) /= E_Component then
21092 -- Do not set Has_Controlled_Component on a class-wide equivalent
21093 -- type. See Make_CW_Equivalent_Type.
21095 elsif not Is_Class_Wide_Equivalent_Type (T)
21096 and then (Has_Controlled_Component (Etype (Component))
21097 or else (Chars (Component) /= Name_uParent
21098 and then Is_Controlled (Etype (Component))))
21100 Set_Has_Controlled_Component (T, True);
21101 Final_Storage_Only :=
21103 and then Finalize_Storage_Only (Etype (Component));
21104 Ctrl_Components := True;
21107 Next_Entity (Component);
21110 -- A Type is Finalize_Storage_Only only if all its controlled components
21113 if Ctrl_Components then
21114 Set_Finalize_Storage_Only (T, Final_Storage_Only);
21117 -- Place reference to end record on the proper entity, which may
21118 -- be a partial view.
21120 if Present (Def) then
21121 Process_End_Label (Def, 'e', Prev_T);
21123 end Record_Type_Definition;
21125 ------------------------
21126 -- Replace_Components --
21127 ------------------------
21129 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
21130 function Process (N : Node_Id) return Traverse_Result;
21136 function Process (N : Node_Id) return Traverse_Result is
21140 if Nkind (N) = N_Discriminant_Specification then
21141 Comp := First_Discriminant (Typ);
21142 while Present (Comp) loop
21143 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21144 Set_Defining_Identifier (N, Comp);
21148 Next_Discriminant (Comp);
21151 elsif Nkind (N) = N_Component_Declaration then
21152 Comp := First_Component (Typ);
21153 while Present (Comp) loop
21154 if Chars (Comp) = Chars (Defining_Identifier (N)) then
21155 Set_Defining_Identifier (N, Comp);
21159 Next_Component (Comp);
21166 procedure Replace is new Traverse_Proc (Process);
21168 -- Start of processing for Replace_Components
21172 end Replace_Components;
21174 -------------------------------
21175 -- Set_Completion_Referenced --
21176 -------------------------------
21178 procedure Set_Completion_Referenced (E : Entity_Id) is
21180 -- If in main unit, mark entity that is a completion as referenced,
21181 -- warnings go on the partial view when needed.
21183 if In_Extended_Main_Source_Unit (E) then
21184 Set_Referenced (E);
21186 end Set_Completion_Referenced;
21188 ---------------------
21189 -- Set_Default_SSO --
21190 ---------------------
21192 procedure Set_Default_SSO (T : Entity_Id) is
21194 case Opt.Default_SSO is
21198 Set_SSO_Set_Low_By_Default (T, True);
21200 Set_SSO_Set_High_By_Default (T, True);
21202 raise Program_Error;
21204 end Set_Default_SSO;
21206 ---------------------
21207 -- Set_Fixed_Range --
21208 ---------------------
21210 -- The range for fixed-point types is complicated by the fact that we
21211 -- do not know the exact end points at the time of the declaration. This
21212 -- is true for three reasons:
21214 -- A size clause may affect the fudging of the end-points.
21215 -- A small clause may affect the values of the end-points.
21216 -- We try to include the end-points if it does not affect the size.
21218 -- This means that the actual end-points must be established at the
21219 -- point when the type is frozen. Meanwhile, we first narrow the range
21220 -- as permitted (so that it will fit if necessary in a small specified
21221 -- size), and then build a range subtree with these narrowed bounds.
21222 -- Set_Fixed_Range constructs the range from real literal values, and
21223 -- sets the range as the Scalar_Range of the given fixed-point type entity.
21225 -- The parent of this range is set to point to the entity so that it is
21226 -- properly hooked into the tree (unlike normal Scalar_Range entries for
21227 -- other scalar types, which are just pointers to the range in the
21228 -- original tree, this would otherwise be an orphan).
21230 -- The tree is left unanalyzed. When the type is frozen, the processing
21231 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
21232 -- analyzed, and uses this as an indication that it should complete
21233 -- work on the range (it will know the final small and size values).
21235 procedure Set_Fixed_Range
21241 S : constant Node_Id :=
21243 Low_Bound => Make_Real_Literal (Loc, Lo),
21244 High_Bound => Make_Real_Literal (Loc, Hi));
21246 Set_Scalar_Range (E, S);
21249 -- Before the freeze point, the bounds of a fixed point are universal
21250 -- and carry the corresponding type.
21252 Set_Etype (Low_Bound (S), Universal_Real);
21253 Set_Etype (High_Bound (S), Universal_Real);
21254 end Set_Fixed_Range;
21256 ----------------------------------
21257 -- Set_Scalar_Range_For_Subtype --
21258 ----------------------------------
21260 procedure Set_Scalar_Range_For_Subtype
21261 (Def_Id : Entity_Id;
21265 Kind : constant Entity_Kind := Ekind (Def_Id);
21268 -- Defend against previous error
21270 if Nkind (R) = N_Error then
21274 Set_Scalar_Range (Def_Id, R);
21276 -- We need to link the range into the tree before resolving it so
21277 -- that types that are referenced, including importantly the subtype
21278 -- itself, are properly frozen (Freeze_Expression requires that the
21279 -- expression be properly linked into the tree). Of course if it is
21280 -- already linked in, then we do not disturb the current link.
21282 if No (Parent (R)) then
21283 Set_Parent (R, Def_Id);
21286 -- Reset the kind of the subtype during analysis of the range, to
21287 -- catch possible premature use in the bounds themselves.
21289 Set_Ekind (Def_Id, E_Void);
21290 Process_Range_Expr_In_Decl (R, Subt, Subtyp => Def_Id);
21291 Set_Ekind (Def_Id, Kind);
21292 end Set_Scalar_Range_For_Subtype;
21294 --------------------------------------------------------
21295 -- Set_Stored_Constraint_From_Discriminant_Constraint --
21296 --------------------------------------------------------
21298 procedure Set_Stored_Constraint_From_Discriminant_Constraint
21302 -- Make sure set if encountered during Expand_To_Stored_Constraint
21304 Set_Stored_Constraint (E, No_Elist);
21306 -- Give it the right value
21308 if Is_Constrained (E) and then Has_Discriminants (E) then
21309 Set_Stored_Constraint (E,
21310 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
21312 end Set_Stored_Constraint_From_Discriminant_Constraint;
21314 -------------------------------------
21315 -- Signed_Integer_Type_Declaration --
21316 -------------------------------------
21318 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
21319 Implicit_Base : Entity_Id;
21320 Base_Typ : Entity_Id;
21323 Errs : Boolean := False;
21327 function Can_Derive_From (E : Entity_Id) return Boolean;
21328 -- Determine whether given bounds allow derivation from specified type
21330 procedure Check_Bound (Expr : Node_Id);
21331 -- Check bound to make sure it is integral and static. If not, post
21332 -- appropriate error message and set Errs flag
21334 ---------------------
21335 -- Can_Derive_From --
21336 ---------------------
21338 -- Note we check both bounds against both end values, to deal with
21339 -- strange types like ones with a range of 0 .. -12341234.
21341 function Can_Derive_From (E : Entity_Id) return Boolean is
21342 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
21343 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
21345 return Lo <= Lo_Val and then Lo_Val <= Hi
21347 Lo <= Hi_Val and then Hi_Val <= Hi;
21348 end Can_Derive_From;
21354 procedure Check_Bound (Expr : Node_Id) is
21356 -- If a range constraint is used as an integer type definition, each
21357 -- bound of the range must be defined by a static expression of some
21358 -- integer type, but the two bounds need not have the same integer
21359 -- type (Negative bounds are allowed.) (RM 3.5.4)
21361 if not Is_Integer_Type (Etype (Expr)) then
21363 ("integer type definition bounds must be of integer type", Expr);
21366 elsif not Is_OK_Static_Expression (Expr) then
21367 Flag_Non_Static_Expr
21368 ("non-static expression used for integer type bound!", Expr);
21371 -- The bounds are folded into literals, and we set their type to be
21372 -- universal, to avoid typing difficulties: we cannot set the type
21373 -- of the literal to the new type, because this would be a forward
21374 -- reference for the back end, and if the original type is user-
21375 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
21378 if Is_Entity_Name (Expr) then
21379 Fold_Uint (Expr, Expr_Value (Expr), True);
21382 Set_Etype (Expr, Universal_Integer);
21386 -- Start of processing for Signed_Integer_Type_Declaration
21389 -- Create an anonymous base type
21392 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
21394 -- Analyze and check the bounds, they can be of any integer type
21396 Lo := Low_Bound (Def);
21397 Hi := High_Bound (Def);
21399 -- Arbitrarily use Integer as the type if either bound had an error
21401 if Hi = Error or else Lo = Error then
21402 Base_Typ := Any_Integer;
21403 Set_Error_Posted (T, True);
21405 -- Here both bounds are OK expressions
21408 Analyze_And_Resolve (Lo, Any_Integer);
21409 Analyze_And_Resolve (Hi, Any_Integer);
21415 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21416 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21419 -- Find type to derive from
21421 Lo_Val := Expr_Value (Lo);
21422 Hi_Val := Expr_Value (Hi);
21424 if Can_Derive_From (Standard_Short_Short_Integer) then
21425 Base_Typ := Base_Type (Standard_Short_Short_Integer);
21427 elsif Can_Derive_From (Standard_Short_Integer) then
21428 Base_Typ := Base_Type (Standard_Short_Integer);
21430 elsif Can_Derive_From (Standard_Integer) then
21431 Base_Typ := Base_Type (Standard_Integer);
21433 elsif Can_Derive_From (Standard_Long_Integer) then
21434 Base_Typ := Base_Type (Standard_Long_Integer);
21436 elsif Can_Derive_From (Standard_Long_Long_Integer) then
21437 Check_Restriction (No_Long_Long_Integers, Def);
21438 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21441 Base_Typ := Base_Type (Standard_Long_Long_Integer);
21442 Error_Msg_N ("integer type definition bounds out of range", Def);
21443 Hi := Type_High_Bound (Standard_Long_Long_Integer);
21444 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
21448 -- Complete both implicit base and declared first subtype entities. The
21449 -- inheritance of the rep item chain ensures that SPARK-related pragmas
21450 -- are not clobbered when the signed integer type acts as a full view of
21453 Set_Etype (Implicit_Base, Base_Typ);
21454 Set_Size_Info (Implicit_Base, Base_Typ);
21455 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
21456 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
21457 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
21459 Set_Ekind (T, E_Signed_Integer_Subtype);
21460 Set_Etype (T, Implicit_Base);
21461 Set_Size_Info (T, Implicit_Base);
21462 Inherit_Rep_Item_Chain (T, Implicit_Base);
21463 Set_Scalar_Range (T, Def);
21464 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
21465 Set_Is_Constrained (T);
21466 end Signed_Integer_Type_Declaration;