1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2009, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Checks; use Checks;
28 with Debug; use Debug;
29 with Elists; use Elists;
30 with Einfo; use Einfo;
31 with Errout; use Errout;
32 with Eval_Fat; use Eval_Fat;
33 with Exp_Ch3; use Exp_Ch3;
34 with Exp_Ch9; use Exp_Ch9;
35 with Exp_Disp; use Exp_Disp;
36 with Exp_Dist; use Exp_Dist;
37 with Exp_Tss; use Exp_Tss;
38 with Exp_Util; use Exp_Util;
39 with Fname; use Fname;
40 with Freeze; use Freeze;
41 with Itypes; use Itypes;
42 with Layout; use Layout;
44 with Lib.Xref; use Lib.Xref;
45 with Namet; use Namet;
46 with Nmake; use Nmake;
48 with Restrict; use Restrict;
49 with Rident; use Rident;
50 with Rtsfind; use Rtsfind;
52 with Sem_Aux; use Sem_Aux;
53 with Sem_Case; use Sem_Case;
54 with Sem_Cat; use Sem_Cat;
55 with Sem_Ch6; use Sem_Ch6;
56 with Sem_Ch7; use Sem_Ch7;
57 with Sem_Ch8; use Sem_Ch8;
58 with Sem_Ch13; use Sem_Ch13;
59 with Sem_Disp; use Sem_Disp;
60 with Sem_Dist; use Sem_Dist;
61 with Sem_Elim; use Sem_Elim;
62 with Sem_Eval; use Sem_Eval;
63 with Sem_Mech; use Sem_Mech;
64 with Sem_Res; use Sem_Res;
65 with Sem_Smem; use Sem_Smem;
66 with Sem_Type; use Sem_Type;
67 with Sem_Util; use Sem_Util;
68 with Sem_Warn; use Sem_Warn;
69 with Stand; use Stand;
70 with Sinfo; use Sinfo;
71 with Snames; use Snames;
72 with Targparm; use Targparm;
73 with Tbuild; use Tbuild;
74 with Ttypes; use Ttypes;
75 with Uintp; use Uintp;
76 with Urealp; use Urealp;
78 package body Sem_Ch3 is
80 -----------------------
81 -- Local Subprograms --
82 -----------------------
84 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id);
85 -- Ada 2005 (AI-251): Add the tag components corresponding to all the
86 -- abstract interface types implemented by a record type or a derived
89 procedure Build_Derived_Type
91 Parent_Type : Entity_Id;
92 Derived_Type : Entity_Id;
93 Is_Completion : Boolean;
94 Derive_Subps : Boolean := True);
95 -- Create and decorate a Derived_Type given the Parent_Type entity. N is
96 -- the N_Full_Type_Declaration node containing the derived type definition.
97 -- Parent_Type is the entity for the parent type in the derived type
98 -- definition and Derived_Type the actual derived type. Is_Completion must
99 -- be set to False if Derived_Type is the N_Defining_Identifier node in N
100 -- (i.e. Derived_Type = Defining_Identifier (N)). In this case N is not the
101 -- completion of a private type declaration. If Is_Completion is set to
102 -- True, N is the completion of a private type declaration and Derived_Type
103 -- is different from the defining identifier inside N (i.e. Derived_Type /=
104 -- Defining_Identifier (N)). Derive_Subps indicates whether the parent
105 -- subprograms should be derived. The only case where this parameter is
106 -- False is when Build_Derived_Type is recursively called to process an
107 -- implicit derived full type for a type derived from a private type (in
108 -- that case the subprograms must only be derived for the private view of
111 -- ??? These flags need a bit of re-examination and re-documentation:
112 -- ??? are they both necessary (both seem related to the recursion)?
114 procedure Build_Derived_Access_Type
116 Parent_Type : Entity_Id;
117 Derived_Type : Entity_Id);
118 -- Subsidiary procedure to Build_Derived_Type. For a derived access type,
119 -- create an implicit base if the parent type is constrained or if the
120 -- subtype indication has a constraint.
122 procedure Build_Derived_Array_Type
124 Parent_Type : Entity_Id;
125 Derived_Type : Entity_Id);
126 -- Subsidiary procedure to Build_Derived_Type. For a derived array type,
127 -- create an implicit base if the parent type is constrained or if the
128 -- subtype indication has a constraint.
130 procedure Build_Derived_Concurrent_Type
132 Parent_Type : Entity_Id;
133 Derived_Type : Entity_Id);
134 -- Subsidiary procedure to Build_Derived_Type. For a derived task or
135 -- protected type, inherit entries and protected subprograms, check
136 -- legality of discriminant constraints if any.
138 procedure Build_Derived_Enumeration_Type
140 Parent_Type : Entity_Id;
141 Derived_Type : Entity_Id);
142 -- Subsidiary procedure to Build_Derived_Type. For a derived enumeration
143 -- type, we must create a new list of literals. Types derived from
144 -- Character and [Wide_]Wide_Character are special-cased.
146 procedure Build_Derived_Numeric_Type
148 Parent_Type : Entity_Id;
149 Derived_Type : Entity_Id);
150 -- Subsidiary procedure to Build_Derived_Type. For numeric types, create
151 -- an anonymous base type, and propagate constraint to subtype if needed.
153 procedure Build_Derived_Private_Type
155 Parent_Type : Entity_Id;
156 Derived_Type : Entity_Id;
157 Is_Completion : Boolean;
158 Derive_Subps : Boolean := True);
159 -- Subsidiary procedure to Build_Derived_Type. This procedure is complex
160 -- because the parent may or may not have a completion, and the derivation
161 -- may itself be a completion.
163 procedure Build_Derived_Record_Type
165 Parent_Type : Entity_Id;
166 Derived_Type : Entity_Id;
167 Derive_Subps : Boolean := True);
168 -- Subsidiary procedure for Build_Derived_Type and
169 -- Analyze_Private_Extension_Declaration used for tagged and untagged
170 -- record types. All parameters are as in Build_Derived_Type except that
171 -- N, in addition to being an N_Full_Type_Declaration node, can also be an
172 -- N_Private_Extension_Declaration node. See the definition of this routine
173 -- for much more info. Derive_Subps indicates whether subprograms should
174 -- be derived from the parent type. The only case where Derive_Subps is
175 -- False is for an implicit derived full type for a type derived from a
176 -- private type (see Build_Derived_Type).
178 procedure Build_Discriminal (Discrim : Entity_Id);
179 -- Create the discriminal corresponding to discriminant Discrim, that is
180 -- the parameter corresponding to Discrim to be used in initialization
181 -- procedures for the type where Discrim is a discriminant. Discriminals
182 -- are not used during semantic analysis, and are not fully defined
183 -- entities until expansion. Thus they are not given a scope until
184 -- initialization procedures are built.
186 function Build_Discriminant_Constraints
189 Derived_Def : Boolean := False) return Elist_Id;
190 -- Validate discriminant constraints and return the list of the constraints
191 -- in order of discriminant declarations, where T is the discriminated
192 -- unconstrained type. Def is the N_Subtype_Indication node where the
193 -- discriminants constraints for T are specified. Derived_Def is True
194 -- when building the discriminant constraints in a derived type definition
195 -- of the form "type D (...) is new T (xxx)". In this case T is the parent
196 -- type and Def is the constraint "(xxx)" on T and this routine sets the
197 -- Corresponding_Discriminant field of the discriminants in the derived
198 -- type D to point to the corresponding discriminants in the parent type T.
200 procedure Build_Discriminated_Subtype
204 Related_Nod : Node_Id;
205 For_Access : Boolean := False);
206 -- Subsidiary procedure to Constrain_Discriminated_Type and to
207 -- Process_Incomplete_Dependents. Given
209 -- T (a possibly discriminated base type)
210 -- Def_Id (a very partially built subtype for T),
212 -- the call completes Def_Id to be the appropriate E_*_Subtype.
214 -- The Elist is the list of discriminant constraints if any (it is set
215 -- to No_Elist if T is not a discriminated type, and to an empty list if
216 -- T has discriminants but there are no discriminant constraints). The
217 -- Related_Nod is the same as Decl_Node in Create_Constrained_Components.
218 -- The For_Access says whether or not this subtype is really constraining
219 -- an access type. That is its sole purpose is the designated type of an
220 -- access type -- in which case a Private_Subtype Is_For_Access_Subtype
221 -- is built to avoid freezing T when the access subtype is frozen.
223 function Build_Scalar_Bound
226 Der_T : Entity_Id) return Node_Id;
227 -- The bounds of a derived scalar type are conversions of the bounds of
228 -- the parent type. Optimize the representation if the bounds are literals.
229 -- Needs a more complete spec--what are the parameters exactly, and what
230 -- exactly is the returned value, and how is Bound affected???
232 procedure Build_Underlying_Full_View
236 -- If the completion of a private type is itself derived from a private
237 -- type, or if the full view of a private subtype is itself private, the
238 -- back-end has no way to compute the actual size of this type. We build
239 -- an internal subtype declaration of the proper parent type to convey
240 -- this information. This extra mechanism is needed because a full
241 -- view cannot itself have a full view (it would get clobbered during
244 procedure Check_Access_Discriminant_Requires_Limited
247 -- Check the restriction that the type to which an access discriminant
248 -- belongs must be a concurrent type or a descendant of a type with
249 -- the reserved word 'limited' in its declaration.
251 procedure Check_Anonymous_Access_Components
255 Comp_List : Node_Id);
256 -- Ada 2005 AI-382: an access component in a record definition can refer to
257 -- the enclosing record, in which case it denotes the type itself, and not
258 -- the current instance of the type. We create an anonymous access type for
259 -- the component, and flag it as an access to a component, so accessibility
260 -- checks are properly performed on it. The declaration of the access type
261 -- is placed ahead of that of the record to prevent order-of-elaboration
262 -- circularity issues in Gigi. We create an incomplete type for the record
263 -- declaration, which is the designated type of the anonymous access.
265 procedure Check_Delta_Expression (E : Node_Id);
266 -- Check that the expression represented by E is suitable for use as a
267 -- delta expression, i.e. it is of real type and is static.
269 procedure Check_Digits_Expression (E : Node_Id);
270 -- Check that the expression represented by E is suitable for use as a
271 -- digits expression, i.e. it is of integer type, positive and static.
273 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id);
274 -- Validate the initialization of an object declaration. T is the required
275 -- type, and Exp is the initialization expression.
277 procedure Check_Interfaces (N : Node_Id; Def : Node_Id);
278 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
280 procedure Check_Or_Process_Discriminants
283 Prev : Entity_Id := Empty);
284 -- If T is the full declaration of an incomplete or private type, check the
285 -- conformance of the discriminants, otherwise process them. Prev is the
286 -- entity of the partial declaration, if any.
288 procedure Check_Real_Bound (Bound : Node_Id);
289 -- Check given bound for being of real type and static. If not, post an
290 -- appropriate message, and rewrite the bound with the real literal zero.
292 procedure Constant_Redeclaration
296 -- Various checks on legality of full declaration of deferred constant.
297 -- Id is the entity for the redeclaration, N is the N_Object_Declaration,
298 -- node. The caller has not yet set any attributes of this entity.
300 function Contain_Interface
302 Ifaces : Elist_Id) return Boolean;
303 -- Ada 2005: Determine whether Iface is present in the list Ifaces
305 procedure Convert_Scalar_Bounds
307 Parent_Type : Entity_Id;
308 Derived_Type : Entity_Id;
310 -- For derived scalar types, convert the bounds in the type definition to
311 -- the derived type, and complete their analysis. Given a constraint of the
312 -- form ".. new T range Lo .. Hi", Lo and Hi are analyzed and resolved with
313 -- T'Base, the parent_type. The bounds of the derived type (the anonymous
314 -- base) are copies of Lo and Hi. Finally, the bounds of the derived
315 -- subtype are conversions of those bounds to the derived_type, so that
316 -- their typing is consistent.
318 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id);
319 -- Copies attributes from array base type T2 to array base type T1. Copies
320 -- only attributes that apply to base types, but not subtypes.
322 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id);
323 -- Copies attributes from array subtype T2 to array subtype T1. Copies
324 -- attributes that apply to both subtypes and base types.
326 procedure Create_Constrained_Components
330 Constraints : Elist_Id);
331 -- Build the list of entities for a constrained discriminated record
332 -- subtype. If a component depends on a discriminant, replace its subtype
333 -- using the discriminant values in the discriminant constraint. Subt
334 -- is the defining identifier for the subtype whose list of constrained
335 -- entities we will create. Decl_Node is the type declaration node where
336 -- we will attach all the itypes created. Typ is the base discriminated
337 -- type for the subtype Subt. Constraints is the list of discriminant
338 -- constraints for Typ.
340 function Constrain_Component_Type
342 Constrained_Typ : Entity_Id;
343 Related_Node : Node_Id;
345 Constraints : Elist_Id) return Entity_Id;
346 -- Given a discriminated base type Typ, a list of discriminant constraint
347 -- Constraints for Typ and a component of Typ, with type Compon_Type,
348 -- create and return the type corresponding to Compon_type where all
349 -- discriminant references are replaced with the corresponding constraint.
350 -- If no discriminant references occur in Compon_Typ then return it as is.
351 -- Constrained_Typ is the final constrained subtype to which the
352 -- constrained Compon_Type belongs. Related_Node is the node where we will
353 -- attach all the itypes created.
355 -- Above description is confused, what is Compon_Type???
357 procedure Constrain_Access
358 (Def_Id : in out Entity_Id;
360 Related_Nod : Node_Id);
361 -- Apply a list of constraints to an access type. If Def_Id is empty, it is
362 -- an anonymous type created for a subtype indication. In that case it is
363 -- created in the procedure and attached to Related_Nod.
365 procedure Constrain_Array
366 (Def_Id : in out Entity_Id;
368 Related_Nod : Node_Id;
369 Related_Id : Entity_Id;
371 -- Apply a list of index constraints to an unconstrained array type. The
372 -- first parameter is the entity for the resulting subtype. A value of
373 -- Empty for Def_Id indicates that an implicit type must be created, but
374 -- creation is delayed (and must be done by this procedure) because other
375 -- subsidiary implicit types must be created first (which is why Def_Id
376 -- is an in/out parameter). The second parameter is a subtype indication
377 -- node for the constrained array to be created (e.g. something of the
378 -- form string (1 .. 10)). Related_Nod gives the place where this type
379 -- has to be inserted in the tree. The Related_Id and Suffix parameters
380 -- are used to build the associated Implicit type name.
382 procedure Constrain_Concurrent
383 (Def_Id : in out Entity_Id;
385 Related_Nod : Node_Id;
386 Related_Id : Entity_Id;
388 -- Apply list of discriminant constraints to an unconstrained concurrent
391 -- SI is the N_Subtype_Indication node containing the constraint and
392 -- the unconstrained type to constrain.
394 -- Def_Id is the entity for the resulting constrained subtype. A value
395 -- of Empty for Def_Id indicates that an implicit type must be created,
396 -- but creation is delayed (and must be done by this procedure) because
397 -- other subsidiary implicit types must be created first (which is why
398 -- Def_Id is an in/out parameter).
400 -- Related_Nod gives the place where this type has to be inserted
403 -- The last two arguments are used to create its external name if needed.
405 function Constrain_Corresponding_Record
406 (Prot_Subt : Entity_Id;
407 Corr_Rec : Entity_Id;
408 Related_Nod : Node_Id;
409 Related_Id : Entity_Id) return Entity_Id;
410 -- When constraining a protected type or task type with discriminants,
411 -- constrain the corresponding record with the same discriminant values.
413 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id);
414 -- Constrain a decimal fixed point type with a digits constraint and/or a
415 -- range constraint, and build E_Decimal_Fixed_Point_Subtype entity.
417 procedure Constrain_Discriminated_Type
420 Related_Nod : Node_Id;
421 For_Access : Boolean := False);
422 -- Process discriminant constraints of composite type. Verify that values
423 -- have been provided for all discriminants, that the original type is
424 -- unconstrained, and that the types of the supplied expressions match
425 -- the discriminant types. The first three parameters are like in routine
426 -- Constrain_Concurrent. See Build_Discriminated_Subtype for an explanation
429 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id);
430 -- Constrain an enumeration type with a range constraint. This is identical
431 -- to Constrain_Integer, but for the Ekind of the resulting subtype.
433 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id);
434 -- Constrain a floating point type with either a digits constraint
435 -- and/or a range constraint, building a E_Floating_Point_Subtype.
437 procedure Constrain_Index
440 Related_Nod : Node_Id;
441 Related_Id : Entity_Id;
444 -- Process an index constraint in a constrained array declaration. The
445 -- constraint can be a subtype name, or a range with or without an explicit
446 -- subtype mark. The index is the corresponding index of the unconstrained
447 -- array. The Related_Id and Suffix parameters are used to build the
448 -- associated Implicit type name.
450 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id);
451 -- Build subtype of a signed or modular integer type
453 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id);
454 -- Constrain an ordinary fixed point type with a range constraint, and
455 -- build an E_Ordinary_Fixed_Point_Subtype entity.
457 procedure Copy_And_Swap (Priv, Full : Entity_Id);
458 -- Copy the Priv entity into the entity of its full declaration then swap
459 -- the two entities in such a manner that the former private type is now
460 -- seen as a full type.
462 procedure Decimal_Fixed_Point_Type_Declaration
465 -- Create a new decimal fixed point type, and apply the constraint to
466 -- obtain a subtype of this new type.
468 procedure Complete_Private_Subtype
471 Full_Base : Entity_Id;
472 Related_Nod : Node_Id);
473 -- Complete the implicit full view of a private subtype by setting the
474 -- appropriate semantic fields. If the full view of the parent is a record
475 -- type, build constrained components of subtype.
477 procedure Derive_Progenitor_Subprograms
478 (Parent_Type : Entity_Id;
479 Tagged_Type : Entity_Id);
480 -- Ada 2005 (AI-251): To complete type derivation, collect the primitive
481 -- operations of progenitors of Tagged_Type, and replace the subsidiary
482 -- subtypes with Tagged_Type, to build the specs of the inherited interface
483 -- primitives. The derived primitives are aliased to those of the
484 -- interface. This routine takes care also of transferring to the full-view
485 -- subprograms associated with the partial-view of Tagged_Type that cover
486 -- interface primitives.
488 procedure Derived_Standard_Character
490 Parent_Type : Entity_Id;
491 Derived_Type : Entity_Id);
492 -- Subsidiary procedure to Build_Derived_Enumeration_Type which handles
493 -- derivations from types Standard.Character and Standard.Wide_Character.
495 procedure Derived_Type_Declaration
498 Is_Completion : Boolean);
499 -- Process a derived type declaration. Build_Derived_Type is invoked
500 -- to process the actual derived type definition. Parameters N and
501 -- Is_Completion have the same meaning as in Build_Derived_Type.
502 -- T is the N_Defining_Identifier for the entity defined in the
503 -- N_Full_Type_Declaration node N, that is T is the derived type.
505 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id);
506 -- Insert each literal in symbol table, as an overloadable identifier. Each
507 -- enumeration type is mapped into a sequence of integers, and each literal
508 -- is defined as a constant with integer value. If any of the literals are
509 -- character literals, the type is a character type, which means that
510 -- strings are legal aggregates for arrays of components of the type.
512 function Expand_To_Stored_Constraint
514 Constraint : Elist_Id) return Elist_Id;
515 -- Given a constraint (i.e. a list of expressions) on the discriminants of
516 -- Typ, expand it into a constraint on the stored discriminants and return
517 -- the new list of expressions constraining the stored discriminants.
519 function Find_Type_Of_Object
521 Related_Nod : Node_Id) return Entity_Id;
522 -- Get type entity for object referenced by Obj_Def, attaching the
523 -- implicit types generated to Related_Nod
525 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id);
526 -- Create a new float and apply the constraint to obtain subtype of it
528 function Has_Range_Constraint (N : Node_Id) return Boolean;
529 -- Given an N_Subtype_Indication node N, return True if a range constraint
530 -- is present, either directly, or as part of a digits or delta constraint.
531 -- In addition, a digits constraint in the decimal case returns True, since
532 -- it establishes a default range if no explicit range is present.
534 function Inherit_Components
536 Parent_Base : Entity_Id;
537 Derived_Base : Entity_Id;
539 Inherit_Discr : Boolean;
540 Discs : Elist_Id) return Elist_Id;
541 -- Called from Build_Derived_Record_Type to inherit the components of
542 -- Parent_Base (a base type) into the Derived_Base (the derived base type).
543 -- For more information on derived types and component inheritance please
544 -- consult the comment above the body of Build_Derived_Record_Type.
546 -- N is the original derived type declaration
548 -- Is_Tagged is set if we are dealing with tagged types
550 -- If Inherit_Discr is set, Derived_Base inherits its discriminants from
551 -- Parent_Base, otherwise no discriminants are inherited.
553 -- Discs gives the list of constraints that apply to Parent_Base in the
554 -- derived type declaration. If Discs is set to No_Elist, then we have
555 -- the following situation:
557 -- type Parent (D1..Dn : ..) is [tagged] record ...;
558 -- type Derived is new Parent [with ...];
560 -- which gets treated as
562 -- type Derived (D1..Dn : ..) is new Parent (D1,..,Dn) [with ...];
564 -- For untagged types the returned value is an association list. The list
565 -- starts from the association (Parent_Base => Derived_Base), and then it
566 -- contains a sequence of the associations of the form
568 -- (Old_Component => New_Component),
570 -- where Old_Component is the Entity_Id of a component in Parent_Base and
571 -- New_Component is the Entity_Id of the corresponding component in
572 -- Derived_Base. For untagged records, this association list is needed when
573 -- copying the record declaration for the derived base. In the tagged case
574 -- the value returned is irrelevant.
576 function Is_Progenitor
578 Typ : Entity_Id) return Boolean;
579 -- Determine whether the interface Iface is implemented by Typ. It requires
580 -- traversing the list of abstract interfaces of the type, as well as that
581 -- of the ancestor types. The predicate is used to determine when a formal
582 -- in the signature of an inherited operation must carry the derived type.
584 function Is_Valid_Constraint_Kind
586 Constraint_Kind : Node_Kind) return Boolean;
587 -- Returns True if it is legal to apply the given kind of constraint to the
588 -- given kind of type (index constraint to an array type, for example).
590 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id);
591 -- Create new modular type. Verify that modulus is in bounds and is
592 -- a power of two (implementation restriction).
594 procedure New_Concatenation_Op (Typ : Entity_Id);
595 -- Create an abbreviated declaration for an operator in order to
596 -- materialize concatenation on array types.
598 procedure Ordinary_Fixed_Point_Type_Declaration
601 -- Create a new ordinary fixed point type, and apply the constraint to
602 -- obtain subtype of it.
604 procedure Prepare_Private_Subtype_Completion
606 Related_Nod : Node_Id);
607 -- Id is a subtype of some private type. Creates the full declaration
608 -- associated with Id whenever possible, i.e. when the full declaration
609 -- of the base type is already known. Records each subtype into
610 -- Private_Dependents of the base type.
612 procedure Process_Incomplete_Dependents
616 -- Process all entities that depend on an incomplete type. There include
617 -- subtypes, subprogram types that mention the incomplete type in their
618 -- profiles, and subprogram with access parameters that designate the
621 -- Inc_T is the defining identifier of an incomplete type declaration, its
622 -- Ekind is E_Incomplete_Type.
624 -- N is the corresponding N_Full_Type_Declaration for Inc_T.
626 -- Full_T is N's defining identifier.
628 -- Subtypes of incomplete types with discriminants are completed when the
629 -- parent type is. This is simpler than private subtypes, because they can
630 -- only appear in the same scope, and there is no need to exchange views.
631 -- Similarly, access_to_subprogram types may have a parameter or a return
632 -- type that is an incomplete type, and that must be replaced with the
635 -- If the full type is tagged, subprogram with access parameters that
636 -- designated the incomplete may be primitive operations of the full type,
637 -- and have to be processed accordingly.
639 procedure Process_Real_Range_Specification (Def : Node_Id);
640 -- Given the type definition for a real type, this procedure processes and
641 -- checks the real range specification of this type definition if one is
642 -- present. If errors are found, error messages are posted, and the
643 -- Real_Range_Specification of Def is reset to Empty.
645 procedure Record_Type_Declaration
649 -- Process a record type declaration (for both untagged and tagged
650 -- records). Parameters T and N are exactly like in procedure
651 -- Derived_Type_Declaration, except that no flag Is_Completion is needed
652 -- for this routine. If this is the completion of an incomplete type
653 -- declaration, Prev is the entity of the incomplete declaration, used for
654 -- cross-referencing. Otherwise Prev = T.
656 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id);
657 -- This routine is used to process the actual record type definition (both
658 -- for untagged and tagged records). Def is a record type definition node.
659 -- This procedure analyzes the components in this record type definition.
660 -- Prev_T is the entity for the enclosing record type. It is provided so
661 -- that its Has_Task flag can be set if any of the component have Has_Task
662 -- set. If the declaration is the completion of an incomplete type
663 -- declaration, Prev_T is the original incomplete type, whose full view is
666 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id);
667 -- Subsidiary to Build_Derived_Record_Type. For untagged records, we
668 -- build a copy of the declaration tree of the parent, and we create
669 -- independently the list of components for the derived type. Semantic
670 -- information uses the component entities, but record representation
671 -- clauses are validated on the declaration tree. This procedure replaces
672 -- discriminants and components in the declaration with those that have
673 -- been created by Inherit_Components.
675 procedure Set_Fixed_Range
680 -- Build a range node with the given bounds and set it as the Scalar_Range
681 -- of the given fixed-point type entity. Loc is the source location used
682 -- for the constructed range. See body for further details.
684 procedure Set_Scalar_Range_For_Subtype
688 -- This routine is used to set the scalar range field for a subtype given
689 -- Def_Id, the entity for the subtype, and R, the range expression for the
690 -- scalar range. Subt provides the parent subtype to be used to analyze,
691 -- resolve, and check the given range.
693 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id);
694 -- Create a new signed integer entity, and apply the constraint to obtain
695 -- the required first named subtype of this type.
697 procedure Set_Stored_Constraint_From_Discriminant_Constraint
699 -- E is some record type. This routine computes E's Stored_Constraint
700 -- from its Discriminant_Constraint.
702 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id);
703 -- Check that an entity in a list of progenitors is an interface,
704 -- emit error otherwise.
706 -----------------------
707 -- Access_Definition --
708 -----------------------
710 function Access_Definition
711 (Related_Nod : Node_Id;
712 N : Node_Id) return Entity_Id
714 Loc : constant Source_Ptr := Sloc (Related_Nod);
715 Anon_Type : Entity_Id;
716 Anon_Scope : Entity_Id;
717 Desig_Type : Entity_Id;
719 Enclosing_Prot_Type : Entity_Id := Empty;
722 if Is_Entry (Current_Scope)
723 and then Is_Task_Type (Etype (Scope (Current_Scope)))
725 Error_Msg_N ("task entries cannot have access parameters", N);
729 -- Ada 2005: for an object declaration the corresponding anonymous
730 -- type is declared in the current scope.
732 -- If the access definition is the return type of another access to
733 -- function, scope is the current one, because it is the one of the
734 -- current type declaration.
736 if Nkind_In (Related_Nod, N_Object_Declaration,
737 N_Access_Function_Definition)
739 Anon_Scope := Current_Scope;
741 -- For the anonymous function result case, retrieve the scope of the
742 -- function specification's associated entity rather than using the
743 -- current scope. The current scope will be the function itself if the
744 -- formal part is currently being analyzed, but will be the parent scope
745 -- in the case of a parameterless function, and we always want to use
746 -- the function's parent scope. Finally, if the function is a child
747 -- unit, we must traverse the tree to retrieve the proper entity.
749 elsif Nkind (Related_Nod) = N_Function_Specification
750 and then Nkind (Parent (N)) /= N_Parameter_Specification
752 -- If the current scope is a protected type, the anonymous access
753 -- is associated with one of the protected operations, and must
754 -- be available in the scope that encloses the protected declaration.
755 -- Otherwise the type is in the scope enclosing the subprogram.
757 -- If the function has formals, The return type of a subprogram
758 -- declaration is analyzed in the scope of the subprogram (see
759 -- Process_Formals) and thus the protected type, if present, is
760 -- the scope of the current function scope.
762 if Ekind (Current_Scope) = E_Protected_Type then
763 Enclosing_Prot_Type := Current_Scope;
765 elsif Ekind (Current_Scope) = E_Function
766 and then Ekind (Scope (Current_Scope)) = E_Protected_Type
768 Enclosing_Prot_Type := Scope (Current_Scope);
771 if Present (Enclosing_Prot_Type) then
772 Anon_Scope := Scope (Enclosing_Prot_Type);
775 Anon_Scope := Scope (Defining_Entity (Related_Nod));
779 -- For access formals, access components, and access discriminants,
780 -- the scope is that of the enclosing declaration,
782 Anon_Scope := Scope (Current_Scope);
787 (E_Anonymous_Access_Type, Related_Nod, Scope_Id => Anon_Scope);
790 and then Ada_Version >= Ada_05
792 Error_Msg_N ("ALL is not permitted for anonymous access types", N);
795 -- Ada 2005 (AI-254): In case of anonymous access to subprograms call
796 -- the corresponding semantic routine
798 if Present (Access_To_Subprogram_Definition (N)) then
799 Access_Subprogram_Declaration
800 (T_Name => Anon_Type,
801 T_Def => Access_To_Subprogram_Definition (N));
803 if Ekind (Anon_Type) = E_Access_Protected_Subprogram_Type then
805 (Anon_Type, E_Anonymous_Access_Protected_Subprogram_Type);
808 (Anon_Type, E_Anonymous_Access_Subprogram_Type);
811 Set_Can_Use_Internal_Rep
812 (Anon_Type, not Always_Compatible_Rep_On_Target);
814 -- If the anonymous access is associated with a protected operation
815 -- create a reference to it after the enclosing protected definition
816 -- because the itype will be used in the subsequent bodies.
818 if Ekind (Current_Scope) = E_Protected_Type then
819 Build_Itype_Reference (Anon_Type, Parent (Current_Scope));
825 Find_Type (Subtype_Mark (N));
826 Desig_Type := Entity (Subtype_Mark (N));
828 Set_Directly_Designated_Type
829 (Anon_Type, Desig_Type);
830 Set_Etype (Anon_Type, Anon_Type);
832 -- Make sure the anonymous access type has size and alignment fields
833 -- set, as required by gigi. This is necessary in the case of the
834 -- Task_Body_Procedure.
836 if not Has_Private_Component (Desig_Type) then
837 Layout_Type (Anon_Type);
840 -- ???The following makes no sense, because Anon_Type is an access type
841 -- and therefore cannot have components, private or otherwise. Hence
842 -- the assertion. Not sure what was meant, here.
843 Set_Depends_On_Private (Anon_Type, Has_Private_Component (Anon_Type));
844 pragma Assert (not Depends_On_Private (Anon_Type));
846 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
847 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
848 -- the null value is allowed. In Ada 95 the null value is never allowed.
850 if Ada_Version >= Ada_05 then
851 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
853 Set_Can_Never_Be_Null (Anon_Type, True);
856 -- The anonymous access type is as public as the discriminated type or
857 -- subprogram that defines it. It is imported (for back-end purposes)
858 -- if the designated type is.
860 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
862 -- Ada 2005 (AI-231): Propagate the access-constant attribute
864 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
866 -- The context is either a subprogram declaration, object declaration,
867 -- or an access discriminant, in a private or a full type declaration.
868 -- In the case of a subprogram, if the designated type is incomplete,
869 -- the operation will be a primitive operation of the full type, to be
870 -- updated subsequently. If the type is imported through a limited_with
871 -- clause, the subprogram is not a primitive operation of the type
872 -- (which is declared elsewhere in some other scope).
874 if Ekind (Desig_Type) = E_Incomplete_Type
875 and then not From_With_Type (Desig_Type)
876 and then Is_Overloadable (Current_Scope)
878 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
879 Set_Has_Delayed_Freeze (Current_Scope);
882 -- Ada 2005: if the designated type is an interface that may contain
883 -- tasks, create a Master entity for the declaration. This must be done
884 -- before expansion of the full declaration, because the declaration may
885 -- include an expression that is an allocator, whose expansion needs the
886 -- proper Master for the created tasks.
888 if Nkind (Related_Nod) = N_Object_Declaration
889 and then Expander_Active
891 if Is_Interface (Desig_Type)
892 and then Is_Limited_Record (Desig_Type)
894 Build_Class_Wide_Master (Anon_Type);
896 -- Similarly, if the type is an anonymous access that designates
897 -- tasks, create a master entity for it in the current context.
899 elsif Has_Task (Desig_Type)
900 and then Comes_From_Source (Related_Nod)
902 if not Has_Master_Entity (Current_Scope) then
904 Make_Object_Declaration (Loc,
905 Defining_Identifier =>
906 Make_Defining_Identifier (Loc, Name_uMaster),
907 Constant_Present => True,
909 New_Reference_To (RTE (RE_Master_Id), Loc),
911 Make_Explicit_Dereference (Loc,
912 New_Reference_To (RTE (RE_Current_Master), Loc)));
914 Insert_Before (Related_Nod, Decl);
917 Set_Master_Id (Anon_Type, Defining_Identifier (Decl));
918 Set_Has_Master_Entity (Current_Scope);
920 Build_Master_Renaming (Related_Nod, Anon_Type);
925 -- For a private component of a protected type, it is imperative that
926 -- the back-end elaborate the type immediately after the protected
927 -- declaration, because this type will be used in the declarations
928 -- created for the component within each protected body, so we must
929 -- create an itype reference for it now.
931 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
932 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
934 -- Similarly, if the access definition is the return result of a
935 -- function, create an itype reference for it because it
936 -- will be used within the function body. For a regular function that
937 -- is not a compilation unit, insert reference after the declaration.
938 -- For a protected operation, insert it after the enclosing protected
939 -- type declaration. In either case, do not create a reference for a
940 -- type obtained through a limited_with clause, because this would
941 -- introduce semantic dependencies.
943 elsif Nkind (Related_Nod) = N_Function_Specification
944 and then not From_With_Type (Desig_Type)
946 if Present (Enclosing_Prot_Type) then
947 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
949 elsif Is_List_Member (Parent (Related_Nod))
950 and then Nkind (Parent (N)) /= N_Parameter_Specification
952 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
955 -- Finally, create an itype reference for an object declaration of
956 -- an anonymous access type. This is strictly necessary only for
957 -- deferred constants, but in any case will avoid out-of-scope
958 -- problems in the back-end.
960 elsif Nkind (Related_Nod) = N_Object_Declaration then
961 Build_Itype_Reference (Anon_Type, Related_Nod);
965 end Access_Definition;
967 -----------------------------------
968 -- Access_Subprogram_Declaration --
969 -----------------------------------
971 procedure Access_Subprogram_Declaration
976 procedure Check_For_Premature_Usage (Def : Node_Id);
977 -- Check that type T_Name is not used, directly or recursively, as a
978 -- parameter or a return type in Def. Def is either a subtype, an
979 -- access_definition, or an access_to_subprogram_definition.
981 -------------------------------
982 -- Check_For_Premature_Usage --
983 -------------------------------
985 procedure Check_For_Premature_Usage (Def : Node_Id) is
989 -- Check for a subtype mark
991 if Nkind (Def) in N_Has_Etype then
992 if Etype (Def) = T_Name then
994 ("type& cannot be used before end of its declaration", Def);
997 -- If this is not a subtype, then this is an access_definition
999 elsif Nkind (Def) = N_Access_Definition then
1000 if Present (Access_To_Subprogram_Definition (Def)) then
1001 Check_For_Premature_Usage
1002 (Access_To_Subprogram_Definition (Def));
1004 Check_For_Premature_Usage (Subtype_Mark (Def));
1007 -- The only cases left are N_Access_Function_Definition and
1008 -- N_Access_Procedure_Definition.
1011 if Present (Parameter_Specifications (Def)) then
1012 Param := First (Parameter_Specifications (Def));
1013 while Present (Param) loop
1014 Check_For_Premature_Usage (Parameter_Type (Param));
1015 Param := Next (Param);
1019 if Nkind (Def) = N_Access_Function_Definition then
1020 Check_For_Premature_Usage (Result_Definition (Def));
1023 end Check_For_Premature_Usage;
1027 Formals : constant List_Id := Parameter_Specifications (T_Def);
1030 Desig_Type : constant Entity_Id :=
1031 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1033 -- Start of processing for Access_Subprogram_Declaration
1036 -- Associate the Itype node with the inner full-type declaration or
1037 -- subprogram spec. This is required to handle nested anonymous
1038 -- declarations. For example:
1041 -- (X : access procedure
1042 -- (Y : access procedure
1045 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1046 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1047 N_Private_Type_Declaration,
1048 N_Private_Extension_Declaration,
1049 N_Procedure_Specification,
1050 N_Function_Specification)
1052 Nkind_In (D_Ityp, N_Object_Declaration,
1053 N_Object_Renaming_Declaration,
1054 N_Formal_Object_Declaration,
1055 N_Formal_Type_Declaration,
1056 N_Task_Type_Declaration,
1057 N_Protected_Type_Declaration))
1059 D_Ityp := Parent (D_Ityp);
1060 pragma Assert (D_Ityp /= Empty);
1063 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1065 if Nkind_In (D_Ityp, N_Procedure_Specification,
1066 N_Function_Specification)
1068 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1070 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1071 N_Object_Declaration,
1072 N_Object_Renaming_Declaration,
1073 N_Formal_Type_Declaration)
1075 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1078 if Nkind (T_Def) = N_Access_Function_Definition then
1079 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1081 Acc : constant Node_Id := Result_Definition (T_Def);
1084 if Present (Access_To_Subprogram_Definition (Acc))
1086 Protected_Present (Access_To_Subprogram_Definition (Acc))
1090 Replace_Anonymous_Access_To_Protected_Subprogram
1096 Access_Definition (T_Def, Result_Definition (T_Def)));
1101 Analyze (Result_Definition (T_Def));
1104 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1107 -- If a null exclusion is imposed on the result type, then
1108 -- create a null-excluding itype (an access subtype) and use
1109 -- it as the function's Etype.
1111 if Is_Access_Type (Typ)
1112 and then Null_Exclusion_In_Return_Present (T_Def)
1114 Set_Etype (Desig_Type,
1115 Create_Null_Excluding_Itype
1117 Related_Nod => T_Def,
1118 Scope_Id => Current_Scope));
1121 if From_With_Type (Typ) then
1123 ("illegal use of incomplete type&",
1124 Result_Definition (T_Def), Typ);
1126 elsif Ekind (Current_Scope) = E_Package
1127 and then In_Private_Part (Current_Scope)
1129 if Ekind (Typ) = E_Incomplete_Type then
1130 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1132 elsif Is_Class_Wide_Type (Typ)
1133 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1136 (Desig_Type, Private_Dependents (Etype (Typ)));
1140 Set_Etype (Desig_Type, Typ);
1145 if not (Is_Type (Etype (Desig_Type))) then
1147 ("expect type in function specification",
1148 Result_Definition (T_Def));
1152 Set_Etype (Desig_Type, Standard_Void_Type);
1155 if Present (Formals) then
1156 Push_Scope (Desig_Type);
1158 -- A bit of a kludge here. These kludges will be removed when Itypes
1159 -- have proper parent pointers to their declarations???
1161 -- Kludge 1) Link defining_identifier of formals. Required by
1162 -- First_Formal to provide its functionality.
1168 F := First (Formals);
1169 while Present (F) loop
1170 if No (Parent (Defining_Identifier (F))) then
1171 Set_Parent (Defining_Identifier (F), F);
1178 Process_Formals (Formals, Parent (T_Def));
1180 -- Kludge 2) End_Scope requires that the parent pointer be set to
1181 -- something reasonable, but Itypes don't have parent pointers. So
1182 -- we set it and then unset it ???
1184 Set_Parent (Desig_Type, T_Name);
1186 Set_Parent (Desig_Type, Empty);
1189 -- Check for premature usage of the type being defined
1191 Check_For_Premature_Usage (T_Def);
1193 -- The return type and/or any parameter type may be incomplete. Mark
1194 -- the subprogram_type as depending on the incomplete type, so that
1195 -- it can be updated when the full type declaration is seen. This
1196 -- only applies to incomplete types declared in some enclosing scope,
1197 -- not to limited views from other packages.
1199 if Present (Formals) then
1200 Formal := First_Formal (Desig_Type);
1201 while Present (Formal) loop
1202 if Ekind (Formal) /= E_In_Parameter
1203 and then Nkind (T_Def) = N_Access_Function_Definition
1205 Error_Msg_N ("functions can only have IN parameters", Formal);
1208 if Ekind (Etype (Formal)) = E_Incomplete_Type
1209 and then In_Open_Scopes (Scope (Etype (Formal)))
1211 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1212 Set_Has_Delayed_Freeze (Desig_Type);
1215 Next_Formal (Formal);
1219 -- If the return type is incomplete, this is legal as long as the
1220 -- type is declared in the current scope and will be completed in
1221 -- it (rather than being part of limited view).
1223 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1224 and then not Has_Delayed_Freeze (Desig_Type)
1225 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1227 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1228 Set_Has_Delayed_Freeze (Desig_Type);
1231 Check_Delayed_Subprogram (Desig_Type);
1233 if Protected_Present (T_Def) then
1234 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1235 Set_Convention (Desig_Type, Convention_Protected);
1237 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1240 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1242 Set_Etype (T_Name, T_Name);
1243 Init_Size_Align (T_Name);
1244 Set_Directly_Designated_Type (T_Name, Desig_Type);
1246 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1248 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1250 Check_Restriction (No_Access_Subprograms, T_Def);
1251 end Access_Subprogram_Declaration;
1253 ----------------------------
1254 -- Access_Type_Declaration --
1255 ----------------------------
1257 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1258 S : constant Node_Id := Subtype_Indication (Def);
1259 P : constant Node_Id := Parent (Def);
1261 -- Check for permissible use of incomplete type
1263 if Nkind (S) /= N_Subtype_Indication then
1266 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1267 Set_Directly_Designated_Type (T, Entity (S));
1269 Set_Directly_Designated_Type (T,
1270 Process_Subtype (S, P, T, 'P'));
1274 Set_Directly_Designated_Type (T,
1275 Process_Subtype (S, P, T, 'P'));
1278 if All_Present (Def) or Constant_Present (Def) then
1279 Set_Ekind (T, E_General_Access_Type);
1281 Set_Ekind (T, E_Access_Type);
1284 if Base_Type (Designated_Type (T)) = T then
1285 Error_Msg_N ("access type cannot designate itself", S);
1287 -- In Ada 2005, the type may have a limited view through some unit
1288 -- in its own context, allowing the following circularity that cannot
1289 -- be detected earlier
1291 elsif Is_Class_Wide_Type (Designated_Type (T))
1292 and then Etype (Designated_Type (T)) = T
1295 ("access type cannot designate its own classwide type", S);
1297 -- Clean up indication of tagged status to prevent cascaded errors
1299 Set_Is_Tagged_Type (T, False);
1304 -- If the type has appeared already in a with_type clause, it is
1305 -- frozen and the pointer size is already set. Else, initialize.
1307 if not From_With_Type (T) then
1308 Init_Size_Align (T);
1311 -- Note that Has_Task is always false, since the access type itself
1312 -- is not a task type. See Einfo for more description on this point.
1313 -- Exactly the same consideration applies to Has_Controlled_Component.
1315 Set_Has_Task (T, False);
1316 Set_Has_Controlled_Component (T, False);
1318 -- Initialize Associated_Final_Chain explicitly to Empty, to avoid
1319 -- problems where an incomplete view of this entity has been previously
1320 -- established by a limited with and an overlaid version of this field
1321 -- (Stored_Constraint) was initialized for the incomplete view.
1323 Set_Associated_Final_Chain (T, Empty);
1325 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1328 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1329 Set_Is_Access_Constant (T, Constant_Present (Def));
1330 end Access_Type_Declaration;
1332 ----------------------------------
1333 -- Add_Interface_Tag_Components --
1334 ----------------------------------
1336 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1337 Loc : constant Source_Ptr := Sloc (N);
1341 procedure Add_Tag (Iface : Entity_Id);
1342 -- Add tag for one of the progenitor interfaces
1348 procedure Add_Tag (Iface : Entity_Id) is
1355 pragma Assert (Is_Tagged_Type (Iface)
1356 and then Is_Interface (Iface));
1359 Make_Component_Definition (Loc,
1360 Aliased_Present => True,
1361 Subtype_Indication =>
1362 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1364 Tag := Make_Defining_Identifier (Loc, New_Internal_Name ('V'));
1367 Make_Component_Declaration (Loc,
1368 Defining_Identifier => Tag,
1369 Component_Definition => Def);
1371 Analyze_Component_Declaration (Decl);
1373 Set_Analyzed (Decl);
1374 Set_Ekind (Tag, E_Component);
1376 Set_Is_Aliased (Tag);
1377 Set_Related_Type (Tag, Iface);
1378 Init_Component_Location (Tag);
1380 pragma Assert (Is_Frozen (Iface));
1382 Set_DT_Entry_Count (Tag,
1383 DT_Entry_Count (First_Entity (Iface)));
1385 if No (Last_Tag) then
1388 Insert_After (Last_Tag, Decl);
1393 -- If the ancestor has discriminants we need to give special support
1394 -- to store the offset_to_top value of the secondary dispatch tables.
1395 -- For this purpose we add a supplementary component just after the
1396 -- field that contains the tag associated with each secondary DT.
1398 if Typ /= Etype (Typ)
1399 and then Has_Discriminants (Etype (Typ))
1402 Make_Component_Definition (Loc,
1403 Subtype_Indication =>
1404 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1407 Make_Defining_Identifier (Loc, New_Internal_Name ('V'));
1410 Make_Component_Declaration (Loc,
1411 Defining_Identifier => Offset,
1412 Component_Definition => Def);
1414 Analyze_Component_Declaration (Decl);
1416 Set_Analyzed (Decl);
1417 Set_Ekind (Offset, E_Component);
1418 Set_Is_Aliased (Offset);
1419 Set_Related_Type (Offset, Iface);
1420 Init_Component_Location (Offset);
1421 Insert_After (Last_Tag, Decl);
1432 -- Start of processing for Add_Interface_Tag_Components
1435 if not RTE_Available (RE_Interface_Tag) then
1437 ("(Ada 2005) interface types not supported by this run-time!",
1442 if Ekind (Typ) /= E_Record_Type
1443 or else (Is_Concurrent_Record_Type (Typ)
1444 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1445 or else (not Is_Concurrent_Record_Type (Typ)
1446 and then No (Interfaces (Typ))
1447 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1452 -- Find the current last tag
1454 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1455 Ext := Record_Extension_Part (Type_Definition (N));
1457 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1458 Ext := Type_Definition (N);
1463 if not (Present (Component_List (Ext))) then
1464 Set_Null_Present (Ext, False);
1466 Set_Component_List (Ext,
1467 Make_Component_List (Loc,
1468 Component_Items => L,
1469 Null_Present => False));
1471 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1472 L := Component_Items
1474 (Record_Extension_Part
1475 (Type_Definition (N))));
1477 L := Component_Items
1479 (Type_Definition (N)));
1482 -- Find the last tag component
1485 while Present (Comp) loop
1486 if Nkind (Comp) = N_Component_Declaration
1487 and then Is_Tag (Defining_Identifier (Comp))
1496 -- At this point L references the list of components and Last_Tag
1497 -- references the current last tag (if any). Now we add the tag
1498 -- corresponding with all the interfaces that are not implemented
1501 if Present (Interfaces (Typ)) then
1502 Elmt := First_Elmt (Interfaces (Typ));
1503 while Present (Elmt) loop
1504 Add_Tag (Node (Elmt));
1508 end Add_Interface_Tag_Components;
1510 -------------------------------------
1511 -- Add_Internal_Interface_Entities --
1512 -------------------------------------
1514 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1517 Iface_Elmt : Elmt_Id;
1518 Iface_Prim : Entity_Id;
1519 Ifaces_List : Elist_Id;
1520 New_Subp : Entity_Id := Empty;
1524 pragma Assert (Ada_Version >= Ada_05
1525 and then Is_Record_Type (Tagged_Type)
1526 and then Is_Tagged_Type (Tagged_Type)
1527 and then Has_Interfaces (Tagged_Type)
1528 and then not Is_Interface (Tagged_Type));
1530 Collect_Interfaces (Tagged_Type, Ifaces_List);
1532 Iface_Elmt := First_Elmt (Ifaces_List);
1533 while Present (Iface_Elmt) loop
1534 Iface := Node (Iface_Elmt);
1536 -- Exclude from this processing interfaces that are parents of
1537 -- Tagged_Type because their primitives are located in the primary
1538 -- dispatch table (and hence no auxiliary internal entities are
1539 -- required to handle secondary dispatch tables in such case).
1541 if not Is_Ancestor (Iface, Tagged_Type) then
1542 Elmt := First_Elmt (Primitive_Operations (Iface));
1543 while Present (Elmt) loop
1544 Iface_Prim := Node (Elmt);
1546 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1548 Find_Primitive_Covering_Interface
1549 (Tagged_Type => Tagged_Type,
1550 Iface_Prim => Iface_Prim);
1552 pragma Assert (Present (Prim));
1555 (New_Subp => New_Subp,
1556 Parent_Subp => Iface_Prim,
1557 Derived_Type => Tagged_Type,
1558 Parent_Type => Iface);
1560 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1561 -- associated with interface types. These entities are
1562 -- only registered in the list of primitives of its
1563 -- corresponding tagged type because they are only used
1564 -- to fill the contents of the secondary dispatch tables.
1565 -- Therefore they are removed from the homonym chains.
1567 Set_Is_Hidden (New_Subp);
1568 Set_Is_Internal (New_Subp);
1569 Set_Alias (New_Subp, Prim);
1570 Set_Is_Abstract_Subprogram (New_Subp,
1571 Is_Abstract_Subprogram (Prim));
1572 Set_Interface_Alias (New_Subp, Iface_Prim);
1574 -- Internal entities associated with interface types are
1575 -- only registered in the list of primitives of the tagged
1576 -- type. They are only used to fill the contents of the
1577 -- secondary dispatch tables. Therefore they are not needed
1578 -- in the homonym chains.
1580 Remove_Homonym (New_Subp);
1582 -- Hidden entities associated with interfaces must have set
1583 -- the Has_Delay_Freeze attribute to ensure that, in case of
1584 -- locally defined tagged types (or compiling with static
1585 -- dispatch tables generation disabled) the corresponding
1586 -- entry of the secondary dispatch table is filled when
1587 -- such an entity is frozen.
1589 Set_Has_Delayed_Freeze (New_Subp);
1596 Next_Elmt (Iface_Elmt);
1598 end Add_Internal_Interface_Entities;
1600 -----------------------------------
1601 -- Analyze_Component_Declaration --
1602 -----------------------------------
1604 procedure Analyze_Component_Declaration (N : Node_Id) is
1605 Id : constant Entity_Id := Defining_Identifier (N);
1606 E : constant Node_Id := Expression (N);
1610 function Contains_POC (Constr : Node_Id) return Boolean;
1611 -- Determines whether a constraint uses the discriminant of a record
1612 -- type thus becoming a per-object constraint (POC).
1614 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1615 -- Typ is the type of the current component, check whether this type is
1616 -- a limited type. Used to validate declaration against that of
1617 -- enclosing record.
1623 function Contains_POC (Constr : Node_Id) return Boolean is
1625 -- Prevent cascaded errors
1627 if Error_Posted (Constr) then
1631 case Nkind (Constr) is
1632 when N_Attribute_Reference =>
1634 Attribute_Name (Constr) = Name_Access
1635 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1637 when N_Discriminant_Association =>
1638 return Denotes_Discriminant (Expression (Constr));
1640 when N_Identifier =>
1641 return Denotes_Discriminant (Constr);
1643 when N_Index_Or_Discriminant_Constraint =>
1648 IDC := First (Constraints (Constr));
1649 while Present (IDC) loop
1651 -- One per-object constraint is sufficient
1653 if Contains_POC (IDC) then
1664 return Denotes_Discriminant (Low_Bound (Constr))
1666 Denotes_Discriminant (High_Bound (Constr));
1668 when N_Range_Constraint =>
1669 return Denotes_Discriminant (Range_Expression (Constr));
1677 ----------------------
1678 -- Is_Known_Limited --
1679 ----------------------
1681 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1682 P : constant Entity_Id := Etype (Typ);
1683 R : constant Entity_Id := Root_Type (Typ);
1686 if Is_Limited_Record (Typ) then
1689 -- If the root type is limited (and not a limited interface)
1690 -- so is the current type
1692 elsif Is_Limited_Record (R)
1694 (not Is_Interface (R)
1695 or else not Is_Limited_Interface (R))
1699 -- Else the type may have a limited interface progenitor, but a
1700 -- limited record parent.
1703 and then Is_Limited_Record (P)
1710 end Is_Known_Limited;
1712 -- Start of processing for Analyze_Component_Declaration
1715 Generate_Definition (Id);
1718 if Present (Subtype_Indication (Component_Definition (N))) then
1719 T := Find_Type_Of_Object
1720 (Subtype_Indication (Component_Definition (N)), N);
1722 -- Ada 2005 (AI-230): Access Definition case
1725 pragma Assert (Present
1726 (Access_Definition (Component_Definition (N))));
1728 T := Access_Definition
1730 N => Access_Definition (Component_Definition (N)));
1731 Set_Is_Local_Anonymous_Access (T);
1733 -- Ada 2005 (AI-254)
1735 if Present (Access_To_Subprogram_Definition
1736 (Access_Definition (Component_Definition (N))))
1737 and then Protected_Present (Access_To_Subprogram_Definition
1739 (Component_Definition (N))))
1741 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1745 -- If the subtype is a constrained subtype of the enclosing record,
1746 -- (which must have a partial view) the back-end does not properly
1747 -- handle the recursion. Rewrite the component declaration with an
1748 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1749 -- the tree directly because side effects have already been removed from
1750 -- discriminant constraints.
1752 if Ekind (T) = E_Access_Subtype
1753 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1754 and then Comes_From_Source (T)
1755 and then Nkind (Parent (T)) = N_Subtype_Declaration
1756 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1759 (Subtype_Indication (Component_Definition (N)),
1760 New_Copy_Tree (Subtype_Indication (Parent (T))));
1761 T := Find_Type_Of_Object
1762 (Subtype_Indication (Component_Definition (N)), N);
1765 -- If the component declaration includes a default expression, then we
1766 -- check that the component is not of a limited type (RM 3.7(5)),
1767 -- and do the special preanalysis of the expression (see section on
1768 -- "Handling of Default and Per-Object Expressions" in the spec of
1772 Preanalyze_Spec_Expression (E, T);
1773 Check_Initialization (T, E);
1775 if Ada_Version >= Ada_05
1776 and then Ekind (T) = E_Anonymous_Access_Type
1777 and then Etype (E) /= Any_Type
1779 -- Check RM 3.9.2(9): "if the expected type for an expression is
1780 -- an anonymous access-to-specific tagged type, then the object
1781 -- designated by the expression shall not be dynamically tagged
1782 -- unless it is a controlling operand in a call on a dispatching
1785 if Is_Tagged_Type (Directly_Designated_Type (T))
1787 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1789 Ekind (Directly_Designated_Type (Etype (E))) =
1793 ("access to specific tagged type required (RM 3.9.2(9))", E);
1796 -- (Ada 2005: AI-230): Accessibility check for anonymous
1799 if Type_Access_Level (Etype (E)) > Type_Access_Level (T) then
1801 ("expression has deeper access level than component " &
1802 "(RM 3.10.2 (12.2))", E);
1805 -- The initialization expression is a reference to an access
1806 -- discriminant. The type of the discriminant is always deeper
1807 -- than any access type.
1809 if Ekind (Etype (E)) = E_Anonymous_Access_Type
1810 and then Is_Entity_Name (E)
1811 and then Ekind (Entity (E)) = E_In_Parameter
1812 and then Present (Discriminal_Link (Entity (E)))
1815 ("discriminant has deeper accessibility level than target",
1821 -- The parent type may be a private view with unknown discriminants,
1822 -- and thus unconstrained. Regular components must be constrained.
1824 if Is_Indefinite_Subtype (T) and then Chars (Id) /= Name_uParent then
1825 if Is_Class_Wide_Type (T) then
1827 ("class-wide subtype with unknown discriminants" &
1828 " in component declaration",
1829 Subtype_Indication (Component_Definition (N)));
1832 ("unconstrained subtype in component declaration",
1833 Subtype_Indication (Component_Definition (N)));
1836 -- Components cannot be abstract, except for the special case of
1837 -- the _Parent field (case of extending an abstract tagged type)
1839 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
1840 Error_Msg_N ("type of a component cannot be abstract", N);
1844 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
1846 -- The component declaration may have a per-object constraint, set
1847 -- the appropriate flag in the defining identifier of the subtype.
1849 if Present (Subtype_Indication (Component_Definition (N))) then
1851 Sindic : constant Node_Id :=
1852 Subtype_Indication (Component_Definition (N));
1854 if Nkind (Sindic) = N_Subtype_Indication
1855 and then Present (Constraint (Sindic))
1856 and then Contains_POC (Constraint (Sindic))
1858 Set_Has_Per_Object_Constraint (Id);
1863 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
1864 -- out some static checks.
1866 if Ada_Version >= Ada_05
1867 and then Can_Never_Be_Null (T)
1869 Null_Exclusion_Static_Checks (N);
1872 -- If this component is private (or depends on a private type), flag the
1873 -- record type to indicate that some operations are not available.
1875 P := Private_Component (T);
1879 -- Check for circular definitions
1881 if P = Any_Type then
1882 Set_Etype (Id, Any_Type);
1884 -- There is a gap in the visibility of operations only if the
1885 -- component type is not defined in the scope of the record type.
1887 elsif Scope (P) = Scope (Current_Scope) then
1890 elsif Is_Limited_Type (P) then
1891 Set_Is_Limited_Composite (Current_Scope);
1894 Set_Is_Private_Composite (Current_Scope);
1899 and then Is_Limited_Type (T)
1900 and then Chars (Id) /= Name_uParent
1901 and then Is_Tagged_Type (Current_Scope)
1903 if Is_Derived_Type (Current_Scope)
1904 and then not Is_Known_Limited (Current_Scope)
1907 ("extension of nonlimited type cannot have limited components",
1910 if Is_Interface (Root_Type (Current_Scope)) then
1912 ("\limitedness is not inherited from limited interface", N);
1914 ("\add LIMITED to type indication", N);
1917 Explain_Limited_Type (T, N);
1918 Set_Etype (Id, Any_Type);
1919 Set_Is_Limited_Composite (Current_Scope, False);
1921 elsif not Is_Derived_Type (Current_Scope)
1922 and then not Is_Limited_Record (Current_Scope)
1923 and then not Is_Concurrent_Type (Current_Scope)
1926 ("nonlimited tagged type cannot have limited components", N);
1927 Explain_Limited_Type (T, N);
1928 Set_Etype (Id, Any_Type);
1929 Set_Is_Limited_Composite (Current_Scope, False);
1933 Set_Original_Record_Component (Id, Id);
1934 end Analyze_Component_Declaration;
1936 --------------------------
1937 -- Analyze_Declarations --
1938 --------------------------
1940 procedure Analyze_Declarations (L : List_Id) is
1942 Freeze_From : Entity_Id := Empty;
1943 Next_Node : Node_Id;
1946 -- Adjust D not to include implicit label declarations, since these
1947 -- have strange Sloc values that result in elaboration check problems.
1948 -- (They have the sloc of the label as found in the source, and that
1949 -- is ahead of the current declarative part).
1955 procedure Adjust_D is
1957 while Present (Prev (D))
1958 and then Nkind (D) = N_Implicit_Label_Declaration
1964 -- Start of processing for Analyze_Declarations
1968 while Present (D) loop
1970 -- Complete analysis of declaration
1973 Next_Node := Next (D);
1975 if No (Freeze_From) then
1976 Freeze_From := First_Entity (Current_Scope);
1979 -- At the end of a declarative part, freeze remaining entities
1980 -- declared in it. The end of the visible declarations of package
1981 -- specification is not the end of a declarative part if private
1982 -- declarations are present. The end of a package declaration is a
1983 -- freezing point only if it a library package. A task definition or
1984 -- protected type definition is not a freeze point either. Finally,
1985 -- we do not freeze entities in generic scopes, because there is no
1986 -- code generated for them and freeze nodes will be generated for
1989 -- The end of a package instantiation is not a freeze point, but
1990 -- for now we make it one, because the generic body is inserted
1991 -- (currently) immediately after. Generic instantiations will not
1992 -- be a freeze point once delayed freezing of bodies is implemented.
1993 -- (This is needed in any case for early instantiations ???).
1995 if No (Next_Node) then
1996 if Nkind_In (Parent (L), N_Component_List,
1998 N_Protected_Definition)
2002 elsif Nkind (Parent (L)) /= N_Package_Specification then
2003 if Nkind (Parent (L)) = N_Package_Body then
2004 Freeze_From := First_Entity (Current_Scope);
2008 Freeze_All (Freeze_From, D);
2009 Freeze_From := Last_Entity (Current_Scope);
2011 elsif Scope (Current_Scope) /= Standard_Standard
2012 and then not Is_Child_Unit (Current_Scope)
2013 and then No (Generic_Parent (Parent (L)))
2017 elsif L /= Visible_Declarations (Parent (L))
2018 or else No (Private_Declarations (Parent (L)))
2019 or else Is_Empty_List (Private_Declarations (Parent (L)))
2022 Freeze_All (Freeze_From, D);
2023 Freeze_From := Last_Entity (Current_Scope);
2026 -- If next node is a body then freeze all types before the body.
2027 -- An exception occurs for some expander-generated bodies. If these
2028 -- are generated at places where in general language rules would not
2029 -- allow a freeze point, then we assume that the expander has
2030 -- explicitly checked that all required types are properly frozen,
2031 -- and we do not cause general freezing here. This special circuit
2032 -- is used when the encountered body is marked as having already
2035 -- In all other cases (bodies that come from source, and expander
2036 -- generated bodies that have not been analyzed yet), freeze all
2037 -- types now. Note that in the latter case, the expander must take
2038 -- care to attach the bodies at a proper place in the tree so as to
2039 -- not cause unwanted freezing at that point.
2041 elsif not Analyzed (Next_Node)
2042 and then (Nkind_In (Next_Node, N_Subprogram_Body,
2048 Nkind (Next_Node) in N_Body_Stub)
2051 Freeze_All (Freeze_From, D);
2052 Freeze_From := Last_Entity (Current_Scope);
2057 end Analyze_Declarations;
2059 ----------------------------------
2060 -- Analyze_Incomplete_Type_Decl --
2061 ----------------------------------
2063 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
2064 F : constant Boolean := Is_Pure (Current_Scope);
2068 Generate_Definition (Defining_Identifier (N));
2070 -- Process an incomplete declaration. The identifier must not have been
2071 -- declared already in the scope. However, an incomplete declaration may
2072 -- appear in the private part of a package, for a private type that has
2073 -- already been declared.
2075 -- In this case, the discriminants (if any) must match
2077 T := Find_Type_Name (N);
2079 Set_Ekind (T, E_Incomplete_Type);
2080 Init_Size_Align (T);
2081 Set_Is_First_Subtype (T, True);
2084 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
2085 -- incomplete types.
2087 if Tagged_Present (N) then
2088 Set_Is_Tagged_Type (T);
2089 Make_Class_Wide_Type (T);
2090 Set_Primitive_Operations (T, New_Elmt_List);
2095 Set_Stored_Constraint (T, No_Elist);
2097 if Present (Discriminant_Specifications (N)) then
2098 Process_Discriminants (N);
2103 -- If the type has discriminants, non-trivial subtypes may be
2104 -- declared before the full view of the type. The full views of those
2105 -- subtypes will be built after the full view of the type.
2107 Set_Private_Dependents (T, New_Elmt_List);
2109 end Analyze_Incomplete_Type_Decl;
2111 -----------------------------------
2112 -- Analyze_Interface_Declaration --
2113 -----------------------------------
2115 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
2116 CW : constant Entity_Id := Class_Wide_Type (T);
2119 Set_Is_Tagged_Type (T);
2121 Set_Is_Limited_Record (T, Limited_Present (Def)
2122 or else Task_Present (Def)
2123 or else Protected_Present (Def)
2124 or else Synchronized_Present (Def));
2126 -- Type is abstract if full declaration carries keyword, or if previous
2127 -- partial view did.
2129 Set_Is_Abstract_Type (T);
2130 Set_Is_Interface (T);
2132 -- Type is a limited interface if it includes the keyword limited, task,
2133 -- protected, or synchronized.
2135 Set_Is_Limited_Interface
2136 (T, Limited_Present (Def)
2137 or else Protected_Present (Def)
2138 or else Synchronized_Present (Def)
2139 or else Task_Present (Def));
2141 Set_Is_Protected_Interface (T, Protected_Present (Def));
2142 Set_Is_Task_Interface (T, Task_Present (Def));
2144 -- Type is a synchronized interface if it includes the keyword task,
2145 -- protected, or synchronized.
2147 Set_Is_Synchronized_Interface
2148 (T, Synchronized_Present (Def)
2149 or else Protected_Present (Def)
2150 or else Task_Present (Def));
2152 Set_Interfaces (T, New_Elmt_List);
2153 Set_Primitive_Operations (T, New_Elmt_List);
2155 -- Complete the decoration of the class-wide entity if it was already
2156 -- built (i.e. during the creation of the limited view)
2158 if Present (CW) then
2159 Set_Is_Interface (CW);
2160 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
2161 Set_Is_Protected_Interface (CW, Is_Protected_Interface (T));
2162 Set_Is_Synchronized_Interface (CW, Is_Synchronized_Interface (T));
2163 Set_Is_Task_Interface (CW, Is_Task_Interface (T));
2166 -- Check runtime support for synchronized interfaces
2168 if VM_Target = No_VM
2169 and then (Is_Task_Interface (T)
2170 or else Is_Protected_Interface (T)
2171 or else Is_Synchronized_Interface (T))
2172 and then not RTE_Available (RE_Select_Specific_Data)
2174 Error_Msg_CRT ("synchronized interfaces", T);
2176 end Analyze_Interface_Declaration;
2178 -----------------------------
2179 -- Analyze_Itype_Reference --
2180 -----------------------------
2182 -- Nothing to do. This node is placed in the tree only for the benefit of
2183 -- back end processing, and has no effect on the semantic processing.
2185 procedure Analyze_Itype_Reference (N : Node_Id) is
2187 pragma Assert (Is_Itype (Itype (N)));
2189 end Analyze_Itype_Reference;
2191 --------------------------------
2192 -- Analyze_Number_Declaration --
2193 --------------------------------
2195 procedure Analyze_Number_Declaration (N : Node_Id) is
2196 Id : constant Entity_Id := Defining_Identifier (N);
2197 E : constant Node_Id := Expression (N);
2199 Index : Interp_Index;
2203 Generate_Definition (Id);
2206 -- This is an optimization of a common case of an integer literal
2208 if Nkind (E) = N_Integer_Literal then
2209 Set_Is_Static_Expression (E, True);
2210 Set_Etype (E, Universal_Integer);
2212 Set_Etype (Id, Universal_Integer);
2213 Set_Ekind (Id, E_Named_Integer);
2214 Set_Is_Frozen (Id, True);
2218 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2220 -- Process expression, replacing error by integer zero, to avoid
2221 -- cascaded errors or aborts further along in the processing
2223 -- Replace Error by integer zero, which seems least likely to
2224 -- cause cascaded errors.
2227 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
2228 Set_Error_Posted (E);
2233 -- Verify that the expression is static and numeric. If
2234 -- the expression is overloaded, we apply the preference
2235 -- rule that favors root numeric types.
2237 if not Is_Overloaded (E) then
2243 Get_First_Interp (E, Index, It);
2244 while Present (It.Typ) loop
2245 if (Is_Integer_Type (It.Typ)
2246 or else Is_Real_Type (It.Typ))
2247 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
2249 if T = Any_Type then
2252 elsif It.Typ = Universal_Real
2253 or else It.Typ = Universal_Integer
2255 -- Choose universal interpretation over any other
2262 Get_Next_Interp (Index, It);
2266 if Is_Integer_Type (T) then
2268 Set_Etype (Id, Universal_Integer);
2269 Set_Ekind (Id, E_Named_Integer);
2271 elsif Is_Real_Type (T) then
2273 -- Because the real value is converted to universal_real, this is a
2274 -- legal context for a universal fixed expression.
2276 if T = Universal_Fixed then
2278 Loc : constant Source_Ptr := Sloc (N);
2279 Conv : constant Node_Id := Make_Type_Conversion (Loc,
2281 New_Occurrence_Of (Universal_Real, Loc),
2282 Expression => Relocate_Node (E));
2289 elsif T = Any_Fixed then
2290 Error_Msg_N ("illegal context for mixed mode operation", E);
2292 -- Expression is of the form : universal_fixed * integer. Try to
2293 -- resolve as universal_real.
2295 T := Universal_Real;
2300 Set_Etype (Id, Universal_Real);
2301 Set_Ekind (Id, E_Named_Real);
2304 Wrong_Type (E, Any_Numeric);
2308 Set_Ekind (Id, E_Constant);
2309 Set_Never_Set_In_Source (Id, True);
2310 Set_Is_True_Constant (Id, True);
2314 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
2315 Set_Etype (E, Etype (Id));
2318 if not Is_OK_Static_Expression (E) then
2319 Flag_Non_Static_Expr
2320 ("non-static expression used in number declaration!", E);
2321 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
2322 Set_Etype (E, Any_Type);
2324 end Analyze_Number_Declaration;
2326 --------------------------------
2327 -- Analyze_Object_Declaration --
2328 --------------------------------
2330 procedure Analyze_Object_Declaration (N : Node_Id) is
2331 Loc : constant Source_Ptr := Sloc (N);
2332 Id : constant Entity_Id := Defining_Identifier (N);
2336 E : Node_Id := Expression (N);
2337 -- E is set to Expression (N) throughout this routine. When
2338 -- Expression (N) is modified, E is changed accordingly.
2340 Prev_Entity : Entity_Id := Empty;
2342 function Count_Tasks (T : Entity_Id) return Uint;
2343 -- This function is called when a non-generic library level object of a
2344 -- task type is declared. Its function is to count the static number of
2345 -- tasks declared within the type (it is only called if Has_Tasks is set
2346 -- for T). As a side effect, if an array of tasks with non-static bounds
2347 -- or a variant record type is encountered, Check_Restrictions is called
2348 -- indicating the count is unknown.
2354 function Count_Tasks (T : Entity_Id) return Uint is
2360 if Is_Task_Type (T) then
2363 elsif Is_Record_Type (T) then
2364 if Has_Discriminants (T) then
2365 Check_Restriction (Max_Tasks, N);
2370 C := First_Component (T);
2371 while Present (C) loop
2372 V := V + Count_Tasks (Etype (C));
2379 elsif Is_Array_Type (T) then
2380 X := First_Index (T);
2381 V := Count_Tasks (Component_Type (T));
2382 while Present (X) loop
2385 if not Is_Static_Subtype (C) then
2386 Check_Restriction (Max_Tasks, N);
2389 V := V * (UI_Max (Uint_0,
2390 Expr_Value (Type_High_Bound (C)) -
2391 Expr_Value (Type_Low_Bound (C)) + Uint_1));
2404 -- Start of processing for Analyze_Object_Declaration
2407 -- There are three kinds of implicit types generated by an
2408 -- object declaration:
2410 -- 1. Those for generated by the original Object Definition
2412 -- 2. Those generated by the Expression
2414 -- 3. Those used to constrained the Object Definition with the
2415 -- expression constraints when it is unconstrained
2417 -- They must be generated in this order to avoid order of elaboration
2418 -- issues. Thus the first step (after entering the name) is to analyze
2419 -- the object definition.
2421 if Constant_Present (N) then
2422 Prev_Entity := Current_Entity_In_Scope (Id);
2424 if Present (Prev_Entity)
2426 -- If the homograph is an implicit subprogram, it is overridden
2427 -- by the current declaration.
2429 ((Is_Overloadable (Prev_Entity)
2430 and then Is_Inherited_Operation (Prev_Entity))
2432 -- The current object is a discriminal generated for an entry
2433 -- family index. Even though the index is a constant, in this
2434 -- particular context there is no true constant redeclaration.
2435 -- Enter_Name will handle the visibility.
2438 (Is_Discriminal (Id)
2439 and then Ekind (Discriminal_Link (Id)) =
2440 E_Entry_Index_Parameter)
2442 -- The current object is the renaming for a generic declared
2443 -- within the instance.
2446 (Ekind (Prev_Entity) = E_Package
2447 and then Nkind (Parent (Prev_Entity)) =
2448 N_Package_Renaming_Declaration
2449 and then not Comes_From_Source (Prev_Entity)
2450 and then Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
2452 Prev_Entity := Empty;
2456 if Present (Prev_Entity) then
2457 Constant_Redeclaration (Id, N, T);
2459 Generate_Reference (Prev_Entity, Id, 'c');
2460 Set_Completion_Referenced (Id);
2462 if Error_Posted (N) then
2464 -- Type mismatch or illegal redeclaration, Do not analyze
2465 -- expression to avoid cascaded errors.
2467 T := Find_Type_Of_Object (Object_Definition (N), N);
2469 Set_Ekind (Id, E_Variable);
2473 -- In the normal case, enter identifier at the start to catch premature
2474 -- usage in the initialization expression.
2477 Generate_Definition (Id);
2480 Mark_Coextensions (N, Object_Definition (N));
2482 T := Find_Type_Of_Object (Object_Definition (N), N);
2484 if Nkind (Object_Definition (N)) = N_Access_Definition
2486 (Access_To_Subprogram_Definition (Object_Definition (N)))
2487 and then Protected_Present
2488 (Access_To_Subprogram_Definition (Object_Definition (N)))
2490 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2493 if Error_Posted (Id) then
2495 Set_Ekind (Id, E_Variable);
2500 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2501 -- out some static checks
2503 if Ada_Version >= Ada_05
2504 and then Can_Never_Be_Null (T)
2506 -- In case of aggregates we must also take care of the correct
2507 -- initialization of nested aggregates bug this is done at the
2508 -- point of the analysis of the aggregate (see sem_aggr.adb)
2510 if Present (Expression (N))
2511 and then Nkind (Expression (N)) = N_Aggregate
2517 Save_Typ : constant Entity_Id := Etype (Id);
2519 Set_Etype (Id, T); -- Temp. decoration for static checks
2520 Null_Exclusion_Static_Checks (N);
2521 Set_Etype (Id, Save_Typ);
2526 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2528 -- If deferred constant, make sure context is appropriate. We detect
2529 -- a deferred constant as a constant declaration with no expression.
2530 -- A deferred constant can appear in a package body if its completion
2531 -- is by means of an interface pragma.
2533 if Constant_Present (N)
2536 -- A deferred constant may appear in the declarative part of the
2537 -- following constructs:
2541 -- extended return statements
2544 -- subprogram bodies
2547 -- When declared inside a package spec, a deferred constant must be
2548 -- completed by a full constant declaration or pragma Import. In all
2549 -- other cases, the only proper completion is pragma Import. Extended
2550 -- return statements are flagged as invalid contexts because they do
2551 -- not have a declarative part and so cannot accommodate the pragma.
2553 if Ekind (Current_Scope) = E_Return_Statement then
2555 ("invalid context for deferred constant declaration (RM 7.4)",
2558 ("\declaration requires an initialization expression",
2560 Set_Constant_Present (N, False);
2562 -- In Ada 83, deferred constant must be of private type
2564 elsif not Is_Private_Type (T) then
2565 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
2567 ("(Ada 83) deferred constant must be private type", N);
2571 -- If not a deferred constant, then object declaration freezes its type
2574 Check_Fully_Declared (T, N);
2575 Freeze_Before (N, T);
2578 -- If the object was created by a constrained array definition, then
2579 -- set the link in both the anonymous base type and anonymous subtype
2580 -- that are built to represent the array type to point to the object.
2582 if Nkind (Object_Definition (Declaration_Node (Id))) =
2583 N_Constrained_Array_Definition
2585 Set_Related_Array_Object (T, Id);
2586 Set_Related_Array_Object (Base_Type (T), Id);
2589 -- Special checks for protected objects not at library level
2591 if Is_Protected_Type (T)
2592 and then not Is_Library_Level_Entity (Id)
2594 Check_Restriction (No_Local_Protected_Objects, Id);
2596 -- Protected objects with interrupt handlers must be at library level
2598 -- Ada 2005: this test is not needed (and the corresponding clause
2599 -- in the RM is removed) because accessibility checks are sufficient
2600 -- to make handlers not at the library level illegal.
2602 if Has_Interrupt_Handler (T)
2603 and then Ada_Version < Ada_05
2606 ("interrupt object can only be declared at library level", Id);
2610 -- The actual subtype of the object is the nominal subtype, unless
2611 -- the nominal one is unconstrained and obtained from the expression.
2615 -- Process initialization expression if present and not in error
2617 if Present (E) and then E /= Error then
2619 -- Generate an error in case of CPP class-wide object initialization.
2620 -- Required because otherwise the expansion of the class-wide
2621 -- assignment would try to use 'size to initialize the object
2622 -- (primitive that is not available in CPP tagged types).
2624 if Is_Class_Wide_Type (Act_T)
2626 (Is_CPP_Class (Root_Type (Etype (Act_T)))
2628 (Present (Full_View (Root_Type (Etype (Act_T))))
2630 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
2633 ("predefined assignment not available for 'C'P'P tagged types",
2637 Mark_Coextensions (N, E);
2640 -- In case of errors detected in the analysis of the expression,
2641 -- decorate it with the expected type to avoid cascaded errors
2643 if No (Etype (E)) then
2647 -- If an initialization expression is present, then we set the
2648 -- Is_True_Constant flag. It will be reset if this is a variable
2649 -- and it is indeed modified.
2651 Set_Is_True_Constant (Id, True);
2653 -- If we are analyzing a constant declaration, set its completion
2654 -- flag after analyzing and resolving the expression.
2656 if Constant_Present (N) then
2657 Set_Has_Completion (Id);
2660 -- Set type and resolve (type may be overridden later on)
2665 -- If E is null and has been replaced by an N_Raise_Constraint_Error
2666 -- node (which was marked already-analyzed), we need to set the type
2667 -- to something other than Any_Access in order to keep gigi happy.
2669 if Etype (E) = Any_Access then
2673 -- If the object is an access to variable, the initialization
2674 -- expression cannot be an access to constant.
2676 if Is_Access_Type (T)
2677 and then not Is_Access_Constant (T)
2678 and then Is_Access_Type (Etype (E))
2679 and then Is_Access_Constant (Etype (E))
2682 ("access to variable cannot be initialized "
2683 & "with an access-to-constant expression", E);
2686 if not Assignment_OK (N) then
2687 Check_Initialization (T, E);
2690 Check_Unset_Reference (E);
2692 -- If this is a variable, then set current value. If this is a
2693 -- declared constant of a scalar type with a static expression,
2694 -- indicate that it is always valid.
2696 if not Constant_Present (N) then
2697 if Compile_Time_Known_Value (E) then
2698 Set_Current_Value (Id, E);
2701 elsif Is_Scalar_Type (T)
2702 and then Is_OK_Static_Expression (E)
2704 Set_Is_Known_Valid (Id);
2707 -- Deal with setting of null flags
2709 if Is_Access_Type (T) then
2710 if Known_Non_Null (E) then
2711 Set_Is_Known_Non_Null (Id, True);
2712 elsif Known_Null (E)
2713 and then not Can_Never_Be_Null (Id)
2715 Set_Is_Known_Null (Id, True);
2719 -- Check incorrect use of dynamically tagged expressions.
2721 if Is_Tagged_Type (T) then
2722 Check_Dynamically_Tagged_Expression
2728 Apply_Scalar_Range_Check (E, T);
2729 Apply_Static_Length_Check (E, T);
2732 -- If the No_Streams restriction is set, check that the type of the
2733 -- object is not, and does not contain, any subtype derived from
2734 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
2735 -- Has_Stream just for efficiency reasons. There is no point in
2736 -- spending time on a Has_Stream check if the restriction is not set.
2738 if Restrictions.Set (No_Streams) then
2739 if Has_Stream (T) then
2740 Check_Restriction (No_Streams, N);
2744 -- Case of unconstrained type
2746 if Is_Indefinite_Subtype (T) then
2748 -- Nothing to do in deferred constant case
2750 if Constant_Present (N) and then No (E) then
2753 -- Case of no initialization present
2756 if No_Initialization (N) then
2759 elsif Is_Class_Wide_Type (T) then
2761 ("initialization required in class-wide declaration ", N);
2765 ("unconstrained subtype not allowed (need initialization)",
2766 Object_Definition (N));
2768 if Is_Record_Type (T) and then Has_Discriminants (T) then
2770 ("\provide initial value or explicit discriminant values",
2771 Object_Definition (N));
2774 ("\or give default discriminant values for type&",
2775 Object_Definition (N), T);
2777 elsif Is_Array_Type (T) then
2779 ("\provide initial value or explicit array bounds",
2780 Object_Definition (N));
2784 -- Case of initialization present but in error. Set initial
2785 -- expression as absent (but do not make above complaints)
2787 elsif E = Error then
2788 Set_Expression (N, Empty);
2791 -- Case of initialization present
2794 -- Not allowed in Ada 83
2796 if not Constant_Present (N) then
2797 if Ada_Version = Ada_83
2798 and then Comes_From_Source (Object_Definition (N))
2801 ("(Ada 83) unconstrained variable not allowed",
2802 Object_Definition (N));
2806 -- Now we constrain the variable from the initializing expression
2808 -- If the expression is an aggregate, it has been expanded into
2809 -- individual assignments. Retrieve the actual type from the
2810 -- expanded construct.
2812 if Is_Array_Type (T)
2813 and then No_Initialization (N)
2814 and then Nkind (Original_Node (E)) = N_Aggregate
2818 -- In case of class-wide interface object declarations we delay
2819 -- the generation of the equivalent record type declarations until
2820 -- its expansion because there are cases in they are not required.
2822 elsif Is_Interface (T) then
2826 Expand_Subtype_From_Expr (N, T, Object_Definition (N), E);
2827 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
2830 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
2832 if Aliased_Present (N) then
2833 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
2836 Freeze_Before (N, Act_T);
2837 Freeze_Before (N, T);
2840 elsif Is_Array_Type (T)
2841 and then No_Initialization (N)
2842 and then Nkind (Original_Node (E)) = N_Aggregate
2844 if not Is_Entity_Name (Object_Definition (N)) then
2846 Check_Compile_Time_Size (Act_T);
2848 if Aliased_Present (N) then
2849 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
2853 -- When the given object definition and the aggregate are specified
2854 -- independently, and their lengths might differ do a length check.
2855 -- This cannot happen if the aggregate is of the form (others =>...)
2857 if not Is_Constrained (T) then
2860 elsif Nkind (E) = N_Raise_Constraint_Error then
2862 -- Aggregate is statically illegal. Place back in declaration
2864 Set_Expression (N, E);
2865 Set_No_Initialization (N, False);
2867 elsif T = Etype (E) then
2870 elsif Nkind (E) = N_Aggregate
2871 and then Present (Component_Associations (E))
2872 and then Present (Choices (First (Component_Associations (E))))
2873 and then Nkind (First
2874 (Choices (First (Component_Associations (E))))) = N_Others_Choice
2879 Apply_Length_Check (E, T);
2882 -- If the type is limited unconstrained with defaulted discriminants
2883 -- and there is no expression, then the object is constrained by the
2884 -- defaults, so it is worthwhile building the corresponding subtype.
2886 elsif (Is_Limited_Record (T)
2887 or else Is_Concurrent_Type (T))
2888 and then not Is_Constrained (T)
2889 and then Has_Discriminants (T)
2892 Act_T := Build_Default_Subtype (T, N);
2894 -- Ada 2005: a limited object may be initialized by means of an
2895 -- aggregate. If the type has default discriminants it has an
2896 -- unconstrained nominal type, Its actual subtype will be obtained
2897 -- from the aggregate, and not from the default discriminants.
2902 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
2904 elsif Present (Underlying_Type (T))
2905 and then not Is_Constrained (Underlying_Type (T))
2906 and then Has_Discriminants (Underlying_Type (T))
2907 and then Nkind (E) = N_Function_Call
2908 and then Constant_Present (N)
2910 -- The back-end has problems with constants of a discriminated type
2911 -- with defaults, if the initial value is a function call. We
2912 -- generate an intermediate temporary for the result of the call.
2913 -- It is unclear why this should make it acceptable to gcc. ???
2915 Remove_Side_Effects (E);
2918 -- Check No_Wide_Characters restriction
2920 if T = Standard_Wide_Character
2921 or else T = Standard_Wide_Wide_Character
2922 or else Root_Type (T) = Standard_Wide_String
2923 or else Root_Type (T) = Standard_Wide_Wide_String
2925 Check_Restriction (No_Wide_Characters, Object_Definition (N));
2928 -- Indicate this is not set in source. Certainly true for constants,
2929 -- and true for variables so far (will be reset for a variable if and
2930 -- when we encounter a modification in the source).
2932 Set_Never_Set_In_Source (Id, True);
2934 -- Now establish the proper kind and type of the object
2936 if Constant_Present (N) then
2937 Set_Ekind (Id, E_Constant);
2938 Set_Is_True_Constant (Id, True);
2941 Set_Ekind (Id, E_Variable);
2943 -- A variable is set as shared passive if it appears in a shared
2944 -- passive package, and is at the outer level. This is not done
2945 -- for entities generated during expansion, because those are
2946 -- always manipulated locally.
2948 if Is_Shared_Passive (Current_Scope)
2949 and then Is_Library_Level_Entity (Id)
2950 and then Comes_From_Source (Id)
2952 Set_Is_Shared_Passive (Id);
2953 Check_Shared_Var (Id, T, N);
2956 -- Set Has_Initial_Value if initializing expression present. Note
2957 -- that if there is no initializing expression, we leave the state
2958 -- of this flag unchanged (usually it will be False, but notably in
2959 -- the case of exception choice variables, it will already be true).
2962 Set_Has_Initial_Value (Id, True);
2966 -- Initialize alignment and size and capture alignment setting
2968 Init_Alignment (Id);
2970 Set_Optimize_Alignment_Flags (Id);
2972 -- Deal with aliased case
2974 if Aliased_Present (N) then
2975 Set_Is_Aliased (Id);
2977 -- If the object is aliased and the type is unconstrained with
2978 -- defaulted discriminants and there is no expression, then the
2979 -- object is constrained by the defaults, so it is worthwhile
2980 -- building the corresponding subtype.
2982 -- Ada 2005 (AI-363): If the aliased object is discriminated and
2983 -- unconstrained, then only establish an actual subtype if the
2984 -- nominal subtype is indefinite. In definite cases the object is
2985 -- unconstrained in Ada 2005.
2988 and then Is_Record_Type (T)
2989 and then not Is_Constrained (T)
2990 and then Has_Discriminants (T)
2991 and then (Ada_Version < Ada_05 or else Is_Indefinite_Subtype (T))
2993 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
2997 -- Now we can set the type of the object
2999 Set_Etype (Id, Act_T);
3001 -- Deal with controlled types
3003 if Has_Controlled_Component (Etype (Id))
3004 or else Is_Controlled (Etype (Id))
3006 if not Is_Library_Level_Entity (Id) then
3007 Check_Restriction (No_Nested_Finalization, N);
3009 Validate_Controlled_Object (Id);
3012 -- Generate a warning when an initialization causes an obvious ABE
3013 -- violation. If the init expression is a simple aggregate there
3014 -- shouldn't be any initialize/adjust call generated. This will be
3015 -- true as soon as aggregates are built in place when possible.
3017 -- ??? at the moment we do not generate warnings for temporaries
3018 -- created for those aggregates although Program_Error might be
3019 -- generated if compiled with -gnato.
3021 if Is_Controlled (Etype (Id))
3022 and then Comes_From_Source (Id)
3025 BT : constant Entity_Id := Base_Type (Etype (Id));
3027 Implicit_Call : Entity_Id;
3028 pragma Warnings (Off, Implicit_Call);
3029 -- ??? what is this for (never referenced!)
3031 function Is_Aggr (N : Node_Id) return Boolean;
3032 -- Check that N is an aggregate
3038 function Is_Aggr (N : Node_Id) return Boolean is
3040 case Nkind (Original_Node (N)) is
3041 when N_Aggregate | N_Extension_Aggregate =>
3044 when N_Qualified_Expression |
3046 N_Unchecked_Type_Conversion =>
3047 return Is_Aggr (Expression (Original_Node (N)));
3055 -- If no underlying type, we already are in an error situation.
3056 -- Do not try to add a warning since we do not have access to
3059 if No (Underlying_Type (BT)) then
3060 Implicit_Call := Empty;
3062 -- A generic type does not have usable primitive operators.
3063 -- Initialization calls are built for instances.
3065 elsif Is_Generic_Type (BT) then
3066 Implicit_Call := Empty;
3068 -- If the init expression is not an aggregate, an adjust call
3069 -- will be generated
3071 elsif Present (E) and then not Is_Aggr (E) then
3072 Implicit_Call := Find_Prim_Op (BT, Name_Adjust);
3074 -- If no init expression and we are not in the deferred
3075 -- constant case, an Initialize call will be generated
3077 elsif No (E) and then not Constant_Present (N) then
3078 Implicit_Call := Find_Prim_Op (BT, Name_Initialize);
3081 Implicit_Call := Empty;
3087 if Has_Task (Etype (Id)) then
3088 Check_Restriction (No_Tasking, N);
3090 -- Deal with counting max tasks
3092 -- Nothing to do if inside a generic
3094 if Inside_A_Generic then
3097 -- If library level entity, then count tasks
3099 elsif Is_Library_Level_Entity (Id) then
3100 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
3102 -- If not library level entity, then indicate we don't know max
3103 -- tasks and also check task hierarchy restriction and blocking
3104 -- operation (since starting a task is definitely blocking!)
3107 Check_Restriction (Max_Tasks, N);
3108 Check_Restriction (No_Task_Hierarchy, N);
3109 Check_Potentially_Blocking_Operation (N);
3112 -- A rather specialized test. If we see two tasks being declared
3113 -- of the same type in the same object declaration, and the task
3114 -- has an entry with an address clause, we know that program error
3115 -- will be raised at run-time since we can't have two tasks with
3116 -- entries at the same address.
3118 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
3123 E := First_Entity (Etype (Id));
3124 while Present (E) loop
3125 if Ekind (E) = E_Entry
3126 and then Present (Get_Attribute_Definition_Clause
3127 (E, Attribute_Address))
3130 ("?more than one task with same entry address", N);
3132 ("\?Program_Error will be raised at run time", N);
3134 Make_Raise_Program_Error (Loc,
3135 Reason => PE_Duplicated_Entry_Address));
3145 -- Some simple constant-propagation: if the expression is a constant
3146 -- string initialized with a literal, share the literal. This avoids
3150 and then Is_Entity_Name (E)
3151 and then Ekind (Entity (E)) = E_Constant
3152 and then Base_Type (Etype (E)) = Standard_String
3155 Val : constant Node_Id := Constant_Value (Entity (E));
3158 and then Nkind (Val) = N_String_Literal
3160 Rewrite (E, New_Copy (Val));
3165 -- Another optimization: if the nominal subtype is unconstrained and
3166 -- the expression is a function call that returns an unconstrained
3167 -- type, rewrite the declaration as a renaming of the result of the
3168 -- call. The exceptions below are cases where the copy is expected,
3169 -- either by the back end (Aliased case) or by the semantics, as for
3170 -- initializing controlled types or copying tags for classwide types.
3173 and then Nkind (E) = N_Explicit_Dereference
3174 and then Nkind (Original_Node (E)) = N_Function_Call
3175 and then not Is_Library_Level_Entity (Id)
3176 and then not Is_Constrained (Underlying_Type (T))
3177 and then not Is_Aliased (Id)
3178 and then not Is_Class_Wide_Type (T)
3179 and then not Is_Controlled (T)
3180 and then not Has_Controlled_Component (Base_Type (T))
3181 and then Expander_Active
3184 Make_Object_Renaming_Declaration (Loc,
3185 Defining_Identifier => Id,
3186 Access_Definition => Empty,
3187 Subtype_Mark => New_Occurrence_Of
3188 (Base_Type (Etype (Id)), Loc),
3191 Set_Renamed_Object (Id, E);
3193 -- Force generation of debugging information for the constant and for
3194 -- the renamed function call.
3196 Set_Debug_Info_Needed (Id);
3197 Set_Debug_Info_Needed (Entity (Prefix (E)));
3200 if Present (Prev_Entity)
3201 and then Is_Frozen (Prev_Entity)
3202 and then not Error_Posted (Id)
3204 Error_Msg_N ("full constant declaration appears too late", N);
3207 Check_Eliminated (Id);
3209 -- Deal with setting In_Private_Part flag if in private part
3211 if Ekind (Scope (Id)) = E_Package
3212 and then In_Private_Part (Scope (Id))
3214 Set_In_Private_Part (Id);
3217 -- Check for violation of No_Local_Timing_Events
3219 if Is_RTE (Etype (Id), RE_Timing_Event)
3220 and then not Is_Library_Level_Entity (Id)
3222 Check_Restriction (No_Local_Timing_Events, N);
3224 end Analyze_Object_Declaration;
3226 ---------------------------
3227 -- Analyze_Others_Choice --
3228 ---------------------------
3230 -- Nothing to do for the others choice node itself, the semantic analysis
3231 -- of the others choice will occur as part of the processing of the parent
3233 procedure Analyze_Others_Choice (N : Node_Id) is
3234 pragma Warnings (Off, N);
3237 end Analyze_Others_Choice;
3239 -------------------------------------------
3240 -- Analyze_Private_Extension_Declaration --
3241 -------------------------------------------
3243 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
3244 T : constant Entity_Id := Defining_Identifier (N);
3245 Indic : constant Node_Id := Subtype_Indication (N);
3246 Parent_Type : Entity_Id;
3247 Parent_Base : Entity_Id;
3250 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
3252 if Is_Non_Empty_List (Interface_List (N)) then
3258 Intf := First (Interface_List (N));
3259 while Present (Intf) loop
3260 T := Find_Type_Of_Subtype_Indic (Intf);
3262 Diagnose_Interface (Intf, T);
3268 Generate_Definition (T);
3271 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
3272 Parent_Base := Base_Type (Parent_Type);
3274 if Parent_Type = Any_Type
3275 or else Etype (Parent_Type) = Any_Type
3277 Set_Ekind (T, Ekind (Parent_Type));
3278 Set_Etype (T, Any_Type);
3281 elsif not Is_Tagged_Type (Parent_Type) then
3283 ("parent of type extension must be a tagged type ", Indic);
3286 elsif Ekind (Parent_Type) = E_Void
3287 or else Ekind (Parent_Type) = E_Incomplete_Type
3289 Error_Msg_N ("premature derivation of incomplete type", Indic);
3292 elsif Is_Concurrent_Type (Parent_Type) then
3294 ("parent type of a private extension cannot be "
3295 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
3297 Set_Etype (T, Any_Type);
3298 Set_Ekind (T, E_Limited_Private_Type);
3299 Set_Private_Dependents (T, New_Elmt_List);
3300 Set_Error_Posted (T);
3304 -- Perhaps the parent type should be changed to the class-wide type's
3305 -- specific type in this case to prevent cascading errors ???
3307 if Is_Class_Wide_Type (Parent_Type) then
3309 ("parent of type extension must not be a class-wide type", Indic);
3313 if (not Is_Package_Or_Generic_Package (Current_Scope)
3314 and then Nkind (Parent (N)) /= N_Generic_Subprogram_Declaration)
3315 or else In_Private_Part (Current_Scope)
3318 Error_Msg_N ("invalid context for private extension", N);
3321 -- Set common attributes
3323 Set_Is_Pure (T, Is_Pure (Current_Scope));
3324 Set_Scope (T, Current_Scope);
3325 Set_Ekind (T, E_Record_Type_With_Private);
3326 Init_Size_Align (T);
3328 Set_Etype (T, Parent_Base);
3329 Set_Has_Task (T, Has_Task (Parent_Base));
3331 Set_Convention (T, Convention (Parent_Type));
3332 Set_First_Rep_Item (T, First_Rep_Item (Parent_Type));
3333 Set_Is_First_Subtype (T);
3334 Make_Class_Wide_Type (T);
3336 if Unknown_Discriminants_Present (N) then
3337 Set_Discriminant_Constraint (T, No_Elist);
3340 Build_Derived_Record_Type (N, Parent_Type, T);
3342 -- Ada 2005 (AI-443): Synchronized private extension or a rewritten
3343 -- synchronized formal derived type.
3345 if Ada_Version >= Ada_05
3346 and then Synchronized_Present (N)
3348 Set_Is_Limited_Record (T);
3350 -- Formal derived type case
3352 if Is_Generic_Type (T) then
3354 -- The parent must be a tagged limited type or a synchronized
3357 if (not Is_Tagged_Type (Parent_Type)
3358 or else not Is_Limited_Type (Parent_Type))
3360 (not Is_Interface (Parent_Type)
3361 or else not Is_Synchronized_Interface (Parent_Type))
3363 Error_Msg_NE ("parent type of & must be tagged limited " &
3364 "or synchronized", N, T);
3367 -- The progenitors (if any) must be limited or synchronized
3370 if Present (Interfaces (T)) then
3373 Iface_Elmt : Elmt_Id;
3376 Iface_Elmt := First_Elmt (Interfaces (T));
3377 while Present (Iface_Elmt) loop
3378 Iface := Node (Iface_Elmt);
3380 if not Is_Limited_Interface (Iface)
3381 and then not Is_Synchronized_Interface (Iface)
3383 Error_Msg_NE ("progenitor & must be limited " &
3384 "or synchronized", N, Iface);
3387 Next_Elmt (Iface_Elmt);
3392 -- Regular derived extension, the parent must be a limited or
3393 -- synchronized interface.
3396 if not Is_Interface (Parent_Type)
3397 or else (not Is_Limited_Interface (Parent_Type)
3399 not Is_Synchronized_Interface (Parent_Type))
3402 ("parent type of & must be limited interface", N, T);
3406 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
3407 -- extension with a synchronized parent must be explicitly declared
3408 -- synchronized, because the full view will be a synchronized type.
3409 -- This must be checked before the check for limited types below,
3410 -- to ensure that types declared limited are not allowed to extend
3411 -- synchronized interfaces.
3413 elsif Is_Interface (Parent_Type)
3414 and then Is_Synchronized_Interface (Parent_Type)
3415 and then not Synchronized_Present (N)
3418 ("private extension of& must be explicitly synchronized",
3421 elsif Limited_Present (N) then
3422 Set_Is_Limited_Record (T);
3424 if not Is_Limited_Type (Parent_Type)
3426 (not Is_Interface (Parent_Type)
3427 or else not Is_Limited_Interface (Parent_Type))
3429 Error_Msg_NE ("parent type& of limited extension must be limited",
3433 end Analyze_Private_Extension_Declaration;
3435 ---------------------------------
3436 -- Analyze_Subtype_Declaration --
3437 ---------------------------------
3439 procedure Analyze_Subtype_Declaration
3441 Skip : Boolean := False)
3443 Id : constant Entity_Id := Defining_Identifier (N);
3445 R_Checks : Check_Result;
3448 Generate_Definition (Id);
3449 Set_Is_Pure (Id, Is_Pure (Current_Scope));
3450 Init_Size_Align (Id);
3452 -- The following guard condition on Enter_Name is to handle cases where
3453 -- the defining identifier has already been entered into the scope but
3454 -- the declaration as a whole needs to be analyzed.
3456 -- This case in particular happens for derived enumeration types. The
3457 -- derived enumeration type is processed as an inserted enumeration type
3458 -- declaration followed by a rewritten subtype declaration. The defining
3459 -- identifier, however, is entered into the name scope very early in the
3460 -- processing of the original type declaration and therefore needs to be
3461 -- avoided here, when the created subtype declaration is analyzed. (See
3462 -- Build_Derived_Types)
3464 -- This also happens when the full view of a private type is derived
3465 -- type with constraints. In this case the entity has been introduced
3466 -- in the private declaration.
3469 or else (Present (Etype (Id))
3470 and then (Is_Private_Type (Etype (Id))
3471 or else Is_Task_Type (Etype (Id))
3472 or else Is_Rewrite_Substitution (N)))
3480 T := Process_Subtype (Subtype_Indication (N), N, Id, 'P');
3482 -- Inherit common attributes
3484 Set_Is_Generic_Type (Id, Is_Generic_Type (Base_Type (T)));
3485 Set_Is_Volatile (Id, Is_Volatile (T));
3486 Set_Treat_As_Volatile (Id, Treat_As_Volatile (T));
3487 Set_Is_Atomic (Id, Is_Atomic (T));
3488 Set_Is_Ada_2005_Only (Id, Is_Ada_2005_Only (T));
3489 Set_Convention (Id, Convention (T));
3491 -- In the case where there is no constraint given in the subtype
3492 -- indication, Process_Subtype just returns the Subtype_Mark, so its
3493 -- semantic attributes must be established here.
3495 if Nkind (Subtype_Indication (N)) /= N_Subtype_Indication then
3496 Set_Etype (Id, Base_Type (T));
3500 Set_Ekind (Id, E_Array_Subtype);
3501 Copy_Array_Subtype_Attributes (Id, T);
3503 when Decimal_Fixed_Point_Kind =>
3504 Set_Ekind (Id, E_Decimal_Fixed_Point_Subtype);
3505 Set_Digits_Value (Id, Digits_Value (T));
3506 Set_Delta_Value (Id, Delta_Value (T));
3507 Set_Scale_Value (Id, Scale_Value (T));
3508 Set_Small_Value (Id, Small_Value (T));
3509 Set_Scalar_Range (Id, Scalar_Range (T));
3510 Set_Machine_Radix_10 (Id, Machine_Radix_10 (T));
3511 Set_Is_Constrained (Id, Is_Constrained (T));
3512 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
3513 Set_RM_Size (Id, RM_Size (T));
3515 when Enumeration_Kind =>
3516 Set_Ekind (Id, E_Enumeration_Subtype);
3517 Set_First_Literal (Id, First_Literal (Base_Type (T)));
3518 Set_Scalar_Range (Id, Scalar_Range (T));
3519 Set_Is_Character_Type (Id, Is_Character_Type (T));
3520 Set_Is_Constrained (Id, Is_Constrained (T));
3521 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
3522 Set_RM_Size (Id, RM_Size (T));
3524 when Ordinary_Fixed_Point_Kind =>
3525 Set_Ekind (Id, E_Ordinary_Fixed_Point_Subtype);
3526 Set_Scalar_Range (Id, Scalar_Range (T));
3527 Set_Small_Value (Id, Small_Value (T));
3528 Set_Delta_Value (Id, Delta_Value (T));
3529 Set_Is_Constrained (Id, Is_Constrained (T));
3530 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
3531 Set_RM_Size (Id, RM_Size (T));
3534 Set_Ekind (Id, E_Floating_Point_Subtype);
3535 Set_Scalar_Range (Id, Scalar_Range (T));
3536 Set_Digits_Value (Id, Digits_Value (T));
3537 Set_Is_Constrained (Id, Is_Constrained (T));
3539 when Signed_Integer_Kind =>
3540 Set_Ekind (Id, E_Signed_Integer_Subtype);
3541 Set_Scalar_Range (Id, Scalar_Range (T));
3542 Set_Is_Constrained (Id, Is_Constrained (T));
3543 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
3544 Set_RM_Size (Id, RM_Size (T));
3546 when Modular_Integer_Kind =>
3547 Set_Ekind (Id, E_Modular_Integer_Subtype);
3548 Set_Scalar_Range (Id, Scalar_Range (T));
3549 Set_Is_Constrained (Id, Is_Constrained (T));
3550 Set_Is_Known_Valid (Id, Is_Known_Valid (T));
3551 Set_RM_Size (Id, RM_Size (T));
3553 when Class_Wide_Kind =>
3554 Set_Ekind (Id, E_Class_Wide_Subtype);
3555 Set_First_Entity (Id, First_Entity (T));
3556 Set_Last_Entity (Id, Last_Entity (T));
3557 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
3558 Set_Cloned_Subtype (Id, T);
3559 Set_Is_Tagged_Type (Id, True);
3560 Set_Has_Unknown_Discriminants
3563 if Ekind (T) = E_Class_Wide_Subtype then
3564 Set_Equivalent_Type (Id, Equivalent_Type (T));
3567 when E_Record_Type | E_Record_Subtype =>
3568 Set_Ekind (Id, E_Record_Subtype);
3570 if Ekind (T) = E_Record_Subtype
3571 and then Present (Cloned_Subtype (T))
3573 Set_Cloned_Subtype (Id, Cloned_Subtype (T));
3575 Set_Cloned_Subtype (Id, T);
3578 Set_First_Entity (Id, First_Entity (T));
3579 Set_Last_Entity (Id, Last_Entity (T));
3580 Set_Has_Discriminants (Id, Has_Discriminants (T));
3581 Set_Is_Constrained (Id, Is_Constrained (T));
3582 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
3583 Set_Has_Unknown_Discriminants
3584 (Id, Has_Unknown_Discriminants (T));
3586 if Has_Discriminants (T) then
3587 Set_Discriminant_Constraint
3588 (Id, Discriminant_Constraint (T));
3589 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
3591 elsif Has_Unknown_Discriminants (Id) then
3592 Set_Discriminant_Constraint (Id, No_Elist);
3595 if Is_Tagged_Type (T) then
3596 Set_Is_Tagged_Type (Id);
3597 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
3598 Set_Primitive_Operations
3599 (Id, Primitive_Operations (T));
3600 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
3602 if Is_Interface (T) then
3603 Set_Is_Interface (Id);
3604 Set_Is_Limited_Interface (Id, Is_Limited_Interface (T));
3608 when Private_Kind =>
3609 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
3610 Set_Has_Discriminants (Id, Has_Discriminants (T));
3611 Set_Is_Constrained (Id, Is_Constrained (T));
3612 Set_First_Entity (Id, First_Entity (T));
3613 Set_Last_Entity (Id, Last_Entity (T));
3614 Set_Private_Dependents (Id, New_Elmt_List);
3615 Set_Is_Limited_Record (Id, Is_Limited_Record (T));
3616 Set_Has_Unknown_Discriminants
3617 (Id, Has_Unknown_Discriminants (T));
3618 Set_Known_To_Have_Preelab_Init
3619 (Id, Known_To_Have_Preelab_Init (T));
3621 if Is_Tagged_Type (T) then
3622 Set_Is_Tagged_Type (Id);
3623 Set_Is_Abstract_Type (Id, Is_Abstract_Type (T));
3624 Set_Primitive_Operations (Id, Primitive_Operations (T));
3625 Set_Class_Wide_Type (Id, Class_Wide_Type (T));
3628 -- In general the attributes of the subtype of a private type
3629 -- are the attributes of the partial view of parent. However,
3630 -- the full view may be a discriminated type, and the subtype
3631 -- must share the discriminant constraint to generate correct
3632 -- calls to initialization procedures.
3634 if Has_Discriminants (T) then
3635 Set_Discriminant_Constraint
3636 (Id, Discriminant_Constraint (T));
3637 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
3639 elsif Present (Full_View (T))
3640 and then Has_Discriminants (Full_View (T))
3642 Set_Discriminant_Constraint
3643 (Id, Discriminant_Constraint (Full_View (T)));
3644 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
3646 -- This would seem semantically correct, but apparently
3647 -- confuses the back-end. To be explained and checked with
3648 -- current version ???
3650 -- Set_Has_Discriminants (Id);
3653 Prepare_Private_Subtype_Completion (Id, N);
3656 Set_Ekind (Id, E_Access_Subtype);
3657 Set_Is_Constrained (Id, Is_Constrained (T));
3658 Set_Is_Access_Constant
3659 (Id, Is_Access_Constant (T));
3660 Set_Directly_Designated_Type
3661 (Id, Designated_Type (T));
3662 Set_Can_Never_Be_Null (Id, Can_Never_Be_Null (T));
3664 -- A Pure library_item must not contain the declaration of a
3665 -- named access type, except within a subprogram, generic
3666 -- subprogram, task unit, or protected unit, or if it has
3667 -- a specified Storage_Size of zero (RM05-10.2.1(15.4-15.5)).
3669 if Comes_From_Source (Id)
3670 and then In_Pure_Unit
3671 and then not In_Subprogram_Task_Protected_Unit
3672 and then not No_Pool_Assigned (Id)
3675 ("named access types not allowed in pure unit", N);
3678 when Concurrent_Kind =>
3679 Set_Ekind (Id, Subtype_Kind (Ekind (T)));
3680 Set_Corresponding_Record_Type (Id,
3681 Corresponding_Record_Type (T));
3682 Set_First_Entity (Id, First_Entity (T));
3683 Set_First_Private_Entity (Id, First_Private_Entity (T));
3684 Set_Has_Discriminants (Id, Has_Discriminants (T));
3685 Set_Is_Constrained (Id, Is_Constrained (T));
3686 Set_Is_Tagged_Type (Id, Is_Tagged_Type (T));
3687 Set_Last_Entity (Id, Last_Entity (T));
3689 if Has_Discriminants (T) then
3690 Set_Discriminant_Constraint (Id,
3691 Discriminant_Constraint (T));
3692 Set_Stored_Constraint_From_Discriminant_Constraint (Id);
3695 when E_Incomplete_Type =>
3696 if Ada_Version >= Ada_05 then
3697 Set_Ekind (Id, E_Incomplete_Subtype);
3699 -- Ada 2005 (AI-412): Decorate an incomplete subtype
3700 -- of an incomplete type visible through a limited
3703 if From_With_Type (T)
3704 and then Present (Non_Limited_View (T))
3706 Set_From_With_Type (Id);
3707 Set_Non_Limited_View (Id, Non_Limited_View (T));
3709 -- Ada 2005 (AI-412): Add the regular incomplete subtype
3710 -- to the private dependents of the original incomplete
3711 -- type for future transformation.
3714 Append_Elmt (Id, Private_Dependents (T));
3717 -- If the subtype name denotes an incomplete type an error
3718 -- was already reported by Process_Subtype.
3721 Set_Etype (Id, Any_Type);
3725 raise Program_Error;
3729 if Etype (Id) = Any_Type then
3733 -- Some common processing on all types
3735 Set_Size_Info (Id, T);
3736 Set_First_Rep_Item (Id, First_Rep_Item (T));
3740 Set_Is_Immediately_Visible (Id, True);
3741 Set_Depends_On_Private (Id, Has_Private_Component (T));
3742 Set_Is_Descendent_Of_Address (Id, Is_Descendent_Of_Address (T));
3744 if Is_Interface (T) then
3745 Set_Is_Interface (Id);
3748 if Present (Generic_Parent_Type (N))
3751 (Parent (Generic_Parent_Type (N))) /= N_Formal_Type_Declaration
3753 (Formal_Type_Definition (Parent (Generic_Parent_Type (N))))
3754 /= N_Formal_Private_Type_Definition)
3756 if Is_Tagged_Type (Id) then
3758 -- If this is a generic actual subtype for a synchronized type,
3759 -- the primitive operations are those of the corresponding record
3760 -- for which there is a separate subtype declaration.
3762 if Is_Concurrent_Type (Id) then
3764 elsif Is_Class_Wide_Type (Id) then
3765 Derive_Subprograms (Generic_Parent_Type (N), Id, Etype (T));
3767 Derive_Subprograms (Generic_Parent_Type (N), Id, T);
3770 elsif Scope (Etype (Id)) /= Standard_Standard then
3771 Derive_Subprograms (Generic_Parent_Type (N), Id);
3775 if Is_Private_Type (T)
3776 and then Present (Full_View (T))
3778 Conditional_Delay (Id, Full_View (T));
3780 -- The subtypes of components or subcomponents of protected types
3781 -- do not need freeze nodes, which would otherwise appear in the
3782 -- wrong scope (before the freeze node for the protected type). The
3783 -- proper subtypes are those of the subcomponents of the corresponding
3786 elsif Ekind (Scope (Id)) /= E_Protected_Type
3787 and then Present (Scope (Scope (Id))) -- error defense!
3788 and then Ekind (Scope (Scope (Id))) /= E_Protected_Type
3790 Conditional_Delay (Id, T);
3793 -- Check that constraint_error is raised for a scalar subtype
3794 -- indication when the lower or upper bound of a non-null range
3795 -- lies outside the range of the type mark.
3797 if Nkind (Subtype_Indication (N)) = N_Subtype_Indication then
3798 if Is_Scalar_Type (Etype (Id))
3799 and then Scalar_Range (Id) /=
3800 Scalar_Range (Etype (Subtype_Mark
3801 (Subtype_Indication (N))))
3805 Etype (Subtype_Mark (Subtype_Indication (N))));
3807 elsif Is_Array_Type (Etype (Id))
3808 and then Present (First_Index (Id))
3810 -- This really should be a subprogram that finds the indications
3813 if ((Nkind (First_Index (Id)) = N_Identifier
3814 and then Ekind (Entity (First_Index (Id))) in Scalar_Kind)
3815 or else Nkind (First_Index (Id)) = N_Subtype_Indication)
3817 Nkind (Scalar_Range (Etype (First_Index (Id)))) = N_Range
3820 Target_Typ : constant Entity_Id :=
3823 (Subtype_Mark (Subtype_Indication (N)))));
3827 (Scalar_Range (Etype (First_Index (Id))),
3829 Etype (First_Index (Id)),
3830 Defining_Identifier (N));
3836 Sloc (Defining_Identifier (N)));
3842 Set_Optimize_Alignment_Flags (Id);
3843 Check_Eliminated (Id);
3844 end Analyze_Subtype_Declaration;
3846 --------------------------------
3847 -- Analyze_Subtype_Indication --
3848 --------------------------------
3850 procedure Analyze_Subtype_Indication (N : Node_Id) is
3851 T : constant Entity_Id := Subtype_Mark (N);
3852 R : constant Node_Id := Range_Expression (Constraint (N));
3859 Set_Etype (N, Etype (R));
3860 Resolve (R, Entity (T));
3862 Set_Error_Posted (R);
3863 Set_Error_Posted (T);
3865 end Analyze_Subtype_Indication;
3867 ------------------------------
3868 -- Analyze_Type_Declaration --
3869 ------------------------------
3871 procedure Analyze_Type_Declaration (N : Node_Id) is
3872 Def : constant Node_Id := Type_Definition (N);
3873 Def_Id : constant Entity_Id := Defining_Identifier (N);
3877 Is_Remote : constant Boolean :=
3878 (Is_Remote_Types (Current_Scope)
3879 or else Is_Remote_Call_Interface (Current_Scope))
3880 and then not (In_Private_Part (Current_Scope)
3881 or else In_Package_Body (Current_Scope));
3883 procedure Check_Ops_From_Incomplete_Type;
3884 -- If there is a tagged incomplete partial view of the type, transfer
3885 -- its operations to the full view, and indicate that the type of the
3886 -- controlling parameter (s) is this full view.
3888 ------------------------------------
3889 -- Check_Ops_From_Incomplete_Type --
3890 ------------------------------------
3892 procedure Check_Ops_From_Incomplete_Type is
3899 and then Ekind (Prev) = E_Incomplete_Type
3900 and then Is_Tagged_Type (Prev)
3901 and then Is_Tagged_Type (T)
3903 Elmt := First_Elmt (Primitive_Operations (Prev));
3904 while Present (Elmt) loop
3906 Prepend_Elmt (Op, Primitive_Operations (T));
3908 Formal := First_Formal (Op);
3909 while Present (Formal) loop
3910 if Etype (Formal) = Prev then
3911 Set_Etype (Formal, T);
3914 Next_Formal (Formal);
3917 if Etype (Op) = Prev then
3924 end Check_Ops_From_Incomplete_Type;
3926 -- Start of processing for Analyze_Type_Declaration
3929 Prev := Find_Type_Name (N);
3931 -- The full view, if present, now points to the current type
3933 -- Ada 2005 (AI-50217): If the type was previously decorated when
3934 -- imported through a LIMITED WITH clause, it appears as incomplete
3935 -- but has no full view.
3936 -- If the incomplete view is tagged, a class_wide type has been
3937 -- created already. Use it for the full view as well, to prevent
3938 -- multiple incompatible class-wide types that may be created for
3939 -- self-referential anonymous access components.
3941 if Ekind (Prev) = E_Incomplete_Type
3942 and then Present (Full_View (Prev))
3944 T := Full_View (Prev);
3946 if Is_Tagged_Type (Prev)
3947 and then Present (Class_Wide_Type (Prev))
3949 Set_Ekind (T, Ekind (Prev)); -- will be reset later
3950 Set_Class_Wide_Type (T, Class_Wide_Type (Prev));
3951 Set_Etype (Class_Wide_Type (T), T);
3958 Set_Is_Pure (T, Is_Pure (Current_Scope));
3960 -- We set the flag Is_First_Subtype here. It is needed to set the
3961 -- corresponding flag for the Implicit class-wide-type created
3962 -- during tagged types processing.
3964 Set_Is_First_Subtype (T, True);
3966 -- Only composite types other than array types are allowed to have
3971 -- For derived types, the rule will be checked once we've figured
3972 -- out the parent type.
3974 when N_Derived_Type_Definition =>
3977 -- For record types, discriminants are allowed
3979 when N_Record_Definition =>
3983 if Present (Discriminant_Specifications (N)) then
3985 ("elementary or array type cannot have discriminants",
3987 (First (Discriminant_Specifications (N))));
3991 -- Elaborate the type definition according to kind, and generate
3992 -- subsidiary (implicit) subtypes where needed. We skip this if it was
3993 -- already done (this happens during the reanalysis that follows a call
3994 -- to the high level optimizer).
3996 if not Analyzed (T) then
4001 when N_Access_To_Subprogram_Definition =>
4002 Access_Subprogram_Declaration (T, Def);
4004 -- If this is a remote access to subprogram, we must create the
4005 -- equivalent fat pointer type, and related subprograms.
4008 Process_Remote_AST_Declaration (N);
4011 -- Validate categorization rule against access type declaration
4012 -- usually a violation in Pure unit, Shared_Passive unit.
4014 Validate_Access_Type_Declaration (T, N);
4016 when N_Access_To_Object_Definition =>
4017 Access_Type_Declaration (T, Def);
4019 -- Validate categorization rule against access type declaration
4020 -- usually a violation in Pure unit, Shared_Passive unit.
4022 Validate_Access_Type_Declaration (T, N);
4024 -- If we are in a Remote_Call_Interface package and define a
4025 -- RACW, then calling stubs and specific stream attributes
4029 and then Is_Remote_Access_To_Class_Wide_Type (Def_Id)
4031 Add_RACW_Features (Def_Id);
4034 -- Set no strict aliasing flag if config pragma seen
4036 if Opt.No_Strict_Aliasing then
4037 Set_No_Strict_Aliasing (Base_Type (Def_Id));
4040 when N_Array_Type_Definition =>
4041 Array_Type_Declaration (T, Def);
4043 when N_Derived_Type_Definition =>
4044 Derived_Type_Declaration (T, N, T /= Def_Id);
4046 when N_Enumeration_Type_Definition =>
4047 Enumeration_Type_Declaration (T, Def);
4049 when N_Floating_Point_Definition =>
4050 Floating_Point_Type_Declaration (T, Def);
4052 when N_Decimal_Fixed_Point_Definition =>
4053 Decimal_Fixed_Point_Type_Declaration (T, Def);
4055 when N_Ordinary_Fixed_Point_Definition =>
4056 Ordinary_Fixed_Point_Type_Declaration (T, Def);
4058 when N_Signed_Integer_Type_Definition =>
4059 Signed_Integer_Type_Declaration (T, Def);
4061 when N_Modular_Type_Definition =>
4062 Modular_Type_Declaration (T, Def);
4064 when N_Record_Definition =>
4065 Record_Type_Declaration (T, N, Prev);
4068 raise Program_Error;
4073 if Etype (T) = Any_Type then
4077 -- Some common processing for all types
4079 Set_Depends_On_Private (T, Has_Private_Component (T));
4080 Check_Ops_From_Incomplete_Type;
4082 -- Both the declared entity, and its anonymous base type if one
4083 -- was created, need freeze nodes allocated.
4086 B : constant Entity_Id := Base_Type (T);
4089 -- In the case where the base type differs from the first subtype, we
4090 -- pre-allocate a freeze node, and set the proper link to the first
4091 -- subtype. Freeze_Entity will use this preallocated freeze node when
4092 -- it freezes the entity.
4094 -- This does not apply if the base type is a generic type, whose
4095 -- declaration is independent of the current derived definition.
4097 if B /= T and then not Is_Generic_Type (B) then
4098 Ensure_Freeze_Node (B);
4099 Set_First_Subtype_Link (Freeze_Node (B), T);
4102 -- A type that is imported through a limited_with clause cannot
4103 -- generate any code, and thus need not be frozen. However, an access
4104 -- type with an imported designated type needs a finalization list,
4105 -- which may be referenced in some other package that has non-limited
4106 -- visibility on the designated type. Thus we must create the
4107 -- finalization list at the point the access type is frozen, to
4108 -- prevent unsatisfied references at link time.
4110 if not From_With_Type (T) or else Is_Access_Type (T) then
4111 Set_Has_Delayed_Freeze (T);
4115 -- Case where T is the full declaration of some private type which has
4116 -- been swapped in Defining_Identifier (N).
4118 if T /= Def_Id and then Is_Private_Type (Def_Id) then
4119 Process_Full_View (N, T, Def_Id);
4121 -- Record the reference. The form of this is a little strange, since
4122 -- the full declaration has been swapped in. So the first parameter
4123 -- here represents the entity to which a reference is made which is
4124 -- the "real" entity, i.e. the one swapped in, and the second
4125 -- parameter provides the reference location.
4127 -- Also, we want to kill Has_Pragma_Unreferenced temporarily here
4128 -- since we don't want a complaint about the full type being an
4129 -- unwanted reference to the private type
4132 B : constant Boolean := Has_Pragma_Unreferenced (T);
4134 Set_Has_Pragma_Unreferenced (T, False);
4135 Generate_Reference (T, T, 'c');
4136 Set_Has_Pragma_Unreferenced (T, B);
4139 Set_Completion_Referenced (Def_Id);
4141 -- For completion of incomplete type, process incomplete dependents
4142 -- and always mark the full type as referenced (it is the incomplete
4143 -- type that we get for any real reference).
4145 elsif Ekind (Prev) = E_Incomplete_Type then
4146 Process_Incomplete_Dependents (N, T, Prev);
4147 Generate_Reference (Prev, Def_Id, 'c');
4148 Set_Completion_Referenced (Def_Id);
4150 -- If not private type or incomplete type completion, this is a real
4151 -- definition of a new entity, so record it.
4154 Generate_Definition (Def_Id);
4157 if Chars (Scope (Def_Id)) = Name_System
4158 and then Chars (Def_Id) = Name_Address
4159 and then Is_Predefined_File_Name (Unit_File_Name (Get_Source_Unit (N)))
4161 Set_Is_Descendent_Of_Address (Def_Id);
4162 Set_Is_Descendent_Of_Address (Base_Type (Def_Id));
4163 Set_Is_Descendent_Of_Address (Prev);
4166 Set_Optimize_Alignment_Flags (Def_Id);
4167 Check_Eliminated (Def_Id);
4168 end Analyze_Type_Declaration;
4170 --------------------------
4171 -- Analyze_Variant_Part --
4172 --------------------------
4174 procedure Analyze_Variant_Part (N : Node_Id) is
4176 procedure Non_Static_Choice_Error (Choice : Node_Id);
4177 -- Error routine invoked by the generic instantiation below when the
4178 -- variant part has a non static choice.
4180 procedure Process_Declarations (Variant : Node_Id);
4181 -- Analyzes all the declarations associated with a Variant. Needed by
4182 -- the generic instantiation below.
4184 package Variant_Choices_Processing is new
4185 Generic_Choices_Processing
4186 (Get_Alternatives => Variants,
4187 Get_Choices => Discrete_Choices,
4188 Process_Empty_Choice => No_OP,
4189 Process_Non_Static_Choice => Non_Static_Choice_Error,
4190 Process_Associated_Node => Process_Declarations);
4191 use Variant_Choices_Processing;
4192 -- Instantiation of the generic choice processing package
4194 -----------------------------
4195 -- Non_Static_Choice_Error --
4196 -----------------------------
4198 procedure Non_Static_Choice_Error (Choice : Node_Id) is
4200 Flag_Non_Static_Expr
4201 ("choice given in variant part is not static!", Choice);
4202 end Non_Static_Choice_Error;
4204 --------------------------
4205 -- Process_Declarations --
4206 --------------------------
4208 procedure Process_Declarations (Variant : Node_Id) is
4210 if not Null_Present (Component_List (Variant)) then
4211 Analyze_Declarations (Component_Items (Component_List (Variant)));
4213 if Present (Variant_Part (Component_List (Variant))) then
4214 Analyze (Variant_Part (Component_List (Variant)));
4217 end Process_Declarations;
4221 Discr_Name : Node_Id;
4222 Discr_Type : Entity_Id;
4224 Case_Table : Choice_Table_Type (1 .. Number_Of_Choices (N));
4226 Dont_Care : Boolean;
4227 Others_Present : Boolean := False;
4229 pragma Warnings (Off, Case_Table);
4230 pragma Warnings (Off, Last_Choice);
4231 pragma Warnings (Off, Dont_Care);
4232 pragma Warnings (Off, Others_Present);
4233 -- We don't care about the assigned values of any of these
4235 -- Start of processing for Analyze_Variant_Part
4238 Discr_Name := Name (N);
4239 Analyze (Discr_Name);
4241 -- If Discr_Name bad, get out (prevent cascaded errors)
4243 if Etype (Discr_Name) = Any_Type then
4247 -- Check invalid discriminant in variant part
4249 if Ekind (Entity (Discr_Name)) /= E_Discriminant then
4250 Error_Msg_N ("invalid discriminant name in variant part", Discr_Name);
4253 Discr_Type := Etype (Entity (Discr_Name));
4255 if not Is_Discrete_Type (Discr_Type) then
4257 ("discriminant in a variant part must be of a discrete type",
4262 -- Call the instantiated Analyze_Choices which does the rest of the work
4265 (N, Discr_Type, Case_Table, Last_Choice, Dont_Care, Others_Present);
4266 end Analyze_Variant_Part;
4268 ----------------------------
4269 -- Array_Type_Declaration --
4270 ----------------------------
4272 procedure Array_Type_Declaration (T : in out Entity_Id; Def : Node_Id) is
4273 Component_Def : constant Node_Id := Component_Definition (Def);
4274 Element_Type : Entity_Id;
4275 Implicit_Base : Entity_Id;
4277 Related_Id : Entity_Id := Empty;
4279 P : constant Node_Id := Parent (Def);
4283 if Nkind (Def) = N_Constrained_Array_Definition then
4284 Index := First (Discrete_Subtype_Definitions (Def));
4286 Index := First (Subtype_Marks (Def));
4289 -- Find proper names for the implicit types which may be public. In case
4290 -- of anonymous arrays we use the name of the first object of that type
4294 Related_Id := Defining_Identifier (P);
4300 while Present (Index) loop
4303 -- Add a subtype declaration for each index of private array type
4304 -- declaration whose etype is also private. For example:
4307 -- type Index is private;
4309 -- type Table is array (Index) of ...
4312 -- This is currently required by the expander for the internally
4313 -- generated equality subprogram of records with variant parts in
4314 -- which the etype of some component is such private type.
4316 if Ekind (Current_Scope) = E_Package
4317 and then In_Private_Part (Current_Scope)
4318 and then Has_Private_Declaration (Etype (Index))
4321 Loc : constant Source_Ptr := Sloc (Def);
4327 Make_Defining_Identifier (Loc,
4328 Chars => New_Internal_Name ('T'));
4329 Set_Is_Internal (New_E);
4332 Make_Subtype_Declaration (Loc,
4333 Defining_Identifier => New_E,
4334 Subtype_Indication =>
4335 New_Occurrence_Of (Etype (Index), Loc));
4337 Insert_Before (Parent (Def), Decl);
4339 Set_Etype (Index, New_E);
4341 -- If the index is a range the Entity attribute is not
4342 -- available. Example:
4345 -- type T is private;
4347 -- type T is new Natural;
4348 -- Table : array (T(1) .. T(10)) of Boolean;
4351 if Nkind (Index) /= N_Range then
4352 Set_Entity (Index, New_E);
4357 Make_Index (Index, P, Related_Id, Nb_Index);
4359 Nb_Index := Nb_Index + 1;
4362 -- Process subtype indication if one is present
4364 if Present (Subtype_Indication (Component_Def)) then
4367 (Subtype_Indication (Component_Def), P, Related_Id, 'C');
4369 -- Ada 2005 (AI-230): Access Definition case
4371 else pragma Assert (Present (Access_Definition (Component_Def)));
4373 -- Indicate that the anonymous access type is created by the
4374 -- array type declaration.
4376 Element_Type := Access_Definition
4378 N => Access_Definition (Component_Def));
4379 Set_Is_Local_Anonymous_Access (Element_Type);
4381 -- Propagate the parent. This field is needed if we have to generate
4382 -- the master_id associated with an anonymous access to task type
4383 -- component (see Expand_N_Full_Type_Declaration.Build_Master)
4385 Set_Parent (Element_Type, Parent (T));
4387 -- Ada 2005 (AI-230): In case of components that are anonymous access
4388 -- types the level of accessibility depends on the enclosing type
4391 Set_Scope (Element_Type, Current_Scope); -- Ada 2005 (AI-230)
4393 -- Ada 2005 (AI-254)
4396 CD : constant Node_Id :=
4397 Access_To_Subprogram_Definition
4398 (Access_Definition (Component_Def));
4400 if Present (CD) and then Protected_Present (CD) then
4402 Replace_Anonymous_Access_To_Protected_Subprogram (Def);
4407 -- Constrained array case
4410 T := Create_Itype (E_Void, P, Related_Id, 'T');
4413 if Nkind (Def) = N_Constrained_Array_Definition then
4415 -- Establish Implicit_Base as unconstrained base type
4417 Implicit_Base := Create_Itype (E_Array_Type, P, Related_Id, 'B');
4419 Set_Etype (Implicit_Base, Implicit_Base);
4420 Set_Scope (Implicit_Base, Current_Scope);
4421 Set_Has_Delayed_Freeze (Implicit_Base);
4423 -- The constrained array type is a subtype of the unconstrained one
4425 Set_Ekind (T, E_Array_Subtype);
4426 Init_Size_Align (T);
4427 Set_Etype (T, Implicit_Base);
4428 Set_Scope (T, Current_Scope);
4429 Set_Is_Constrained (T, True);
4430 Set_First_Index (T, First (Discrete_Subtype_Definitions (Def)));
4431 Set_Has_Delayed_Freeze (T);
4433 -- Complete setup of implicit base type
4435 Set_First_Index (Implicit_Base, First_Index (T));
4436 Set_Component_Type (Implicit_Base, Element_Type);
4437 Set_Has_Task (Implicit_Base, Has_Task (Element_Type));
4438 Set_Component_Size (Implicit_Base, Uint_0);
4439 Set_Packed_Array_Type (Implicit_Base, Empty);
4440 Set_Has_Controlled_Component
4441 (Implicit_Base, Has_Controlled_Component
4443 or else Is_Controlled
4445 Set_Finalize_Storage_Only
4446 (Implicit_Base, Finalize_Storage_Only
4449 -- Unconstrained array case
4452 Set_Ekind (T, E_Array_Type);
4453 Init_Size_Align (T);
4455 Set_Scope (T, Current_Scope);
4456 Set_Component_Size (T, Uint_0);
4457 Set_Is_Constrained (T, False);
4458 Set_First_Index (T, First (Subtype_Marks (Def)));
4459 Set_Has_Delayed_Freeze (T, True);
4460 Set_Has_Task (T, Has_Task (Element_Type));
4461 Set_Has_Controlled_Component (T, Has_Controlled_Component
4464 Is_Controlled (Element_Type));
4465 Set_Finalize_Storage_Only (T, Finalize_Storage_Only
4469 -- Common attributes for both cases
4471 Set_Component_Type (Base_Type (T), Element_Type);
4472 Set_Packed_Array_Type (T, Empty);
4474 if Aliased_Present (Component_Definition (Def)) then
4475 Set_Has_Aliased_Components (Etype (T));
4478 -- Ada 2005 (AI-231): Propagate the null-excluding attribute to the
4479 -- array type to ensure that objects of this type are initialized.
4481 if Ada_Version >= Ada_05
4482 and then Can_Never_Be_Null (Element_Type)
4484 Set_Can_Never_Be_Null (T);
4486 if Null_Exclusion_Present (Component_Definition (Def))
4488 -- No need to check itypes because in their case this check was
4489 -- done at their point of creation
4491 and then not Is_Itype (Element_Type)
4494 ("`NOT NULL` not allowed (null already excluded)",
4495 Subtype_Indication (Component_Definition (Def)));
4499 Priv := Private_Component (Element_Type);
4501 if Present (Priv) then
4503 -- Check for circular definitions
4505 if Priv = Any_Type then
4506 Set_Component_Type (Etype (T), Any_Type);
4508 -- There is a gap in the visibility of operations on the composite
4509 -- type only if the component type is defined in a different scope.
4511 elsif Scope (Priv) = Current_Scope then
4514 elsif Is_Limited_Type (Priv) then
4515 Set_Is_Limited_Composite (Etype (T));
4516 Set_Is_Limited_Composite (T);
4518 Set_Is_Private_Composite (Etype (T));
4519 Set_Is_Private_Composite (T);
4523 -- A syntax error in the declaration itself may lead to an empty index
4524 -- list, in which case do a minimal patch.
4526 if No (First_Index (T)) then
4527 Error_Msg_N ("missing index definition in array type declaration", T);
4530 Indices : constant List_Id :=
4531 New_List (New_Occurrence_Of (Any_Id, Sloc (T)));
4533 Set_Discrete_Subtype_Definitions (Def, Indices);
4534 Set_First_Index (T, First (Indices));
4539 -- Create a concatenation operator for the new type. Internal array
4540 -- types created for packed entities do not need such, they are
4541 -- compatible with the user-defined type.
4543 if Number_Dimensions (T) = 1
4544 and then not Is_Packed_Array_Type (T)
4546 New_Concatenation_Op (T);
4549 -- In the case of an unconstrained array the parser has already verified
4550 -- that all the indices are unconstrained but we still need to make sure
4551 -- that the element type is constrained.
4553 if Is_Indefinite_Subtype (Element_Type) then
4555 ("unconstrained element type in array declaration",
4556 Subtype_Indication (Component_Def));
4558 elsif Is_Abstract_Type (Element_Type) then
4560 ("the type of a component cannot be abstract",
4561 Subtype_Indication (Component_Def));
4563 end Array_Type_Declaration;
4565 ------------------------------------------------------
4566 -- Replace_Anonymous_Access_To_Protected_Subprogram --
4567 ------------------------------------------------------
4569 function Replace_Anonymous_Access_To_Protected_Subprogram
4570 (N : Node_Id) return Entity_Id
4572 Loc : constant Source_Ptr := Sloc (N);
4574 Curr_Scope : constant Scope_Stack_Entry :=
4575 Scope_Stack.Table (Scope_Stack.Last);
4577 Anon : constant Entity_Id :=
4578 Make_Defining_Identifier (Loc,
4579 Chars => New_Internal_Name ('S'));
4587 Set_Is_Internal (Anon);
4590 when N_Component_Declaration |
4591 N_Unconstrained_Array_Definition |
4592 N_Constrained_Array_Definition =>
4593 Comp := Component_Definition (N);
4594 Acc := Access_Definition (Comp);
4596 when N_Discriminant_Specification =>
4597 Comp := Discriminant_Type (N);
4600 when N_Parameter_Specification =>
4601 Comp := Parameter_Type (N);
4604 when N_Access_Function_Definition =>
4605 Comp := Result_Definition (N);
4608 when N_Object_Declaration =>
4609 Comp := Object_Definition (N);
4612 when N_Function_Specification =>
4613 Comp := Result_Definition (N);
4617 raise Program_Error;
4620 Decl := Make_Full_Type_Declaration (Loc,
4621 Defining_Identifier => Anon,
4623 Copy_Separate_Tree (Access_To_Subprogram_Definition (Acc)));
4625 Mark_Rewrite_Insertion (Decl);
4627 -- Insert the new declaration in the nearest enclosing scope. If the
4628 -- node is a body and N is its return type, the declaration belongs in
4629 -- the enclosing scope.
4633 if Nkind (P) = N_Subprogram_Body
4634 and then Nkind (N) = N_Function_Specification
4639 while Present (P) and then not Has_Declarations (P) loop
4643 pragma Assert (Present (P));
4645 if Nkind (P) = N_Package_Specification then
4646 Prepend (Decl, Visible_Declarations (P));
4648 Prepend (Decl, Declarations (P));
4651 -- Replace the anonymous type with an occurrence of the new declaration.
4652 -- In all cases the rewritten node does not have the null-exclusion
4653 -- attribute because (if present) it was already inherited by the
4654 -- anonymous entity (Anon). Thus, in case of components we do not
4655 -- inherit this attribute.
4657 if Nkind (N) = N_Parameter_Specification then
4658 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
4659 Set_Etype (Defining_Identifier (N), Anon);
4660 Set_Null_Exclusion_Present (N, False);
4662 elsif Nkind (N) = N_Object_Declaration then
4663 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
4664 Set_Etype (Defining_Identifier (N), Anon);
4666 elsif Nkind (N) = N_Access_Function_Definition then
4667 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
4669 elsif Nkind (N) = N_Function_Specification then
4670 Rewrite (Comp, New_Occurrence_Of (Anon, Loc));
4671 Set_Etype (Defining_Unit_Name (N), Anon);
4675 Make_Component_Definition (Loc,
4676 Subtype_Indication => New_Occurrence_Of (Anon, Loc)));
4679 Mark_Rewrite_Insertion (Comp);
4681 if Nkind_In (N, N_Object_Declaration, N_Access_Function_Definition) then
4685 -- Temporarily remove the current scope (record or subprogram) from
4686 -- the stack to add the new declarations to the enclosing scope.
4688 Scope_Stack.Decrement_Last;
4690 Set_Is_Itype (Anon);
4691 Scope_Stack.Append (Curr_Scope);
4694 Set_Ekind (Anon, E_Anonymous_Access_Protected_Subprogram_Type);
4695 Set_Can_Use_Internal_Rep (Anon, not Always_Compatible_Rep_On_Target);
4697 end Replace_Anonymous_Access_To_Protected_Subprogram;
4699 -------------------------------
4700 -- Build_Derived_Access_Type --
4701 -------------------------------
4703 procedure Build_Derived_Access_Type
4705 Parent_Type : Entity_Id;
4706 Derived_Type : Entity_Id)
4708 S : constant Node_Id := Subtype_Indication (Type_Definition (N));
4710 Desig_Type : Entity_Id;
4712 Discr_Con_Elist : Elist_Id;
4713 Discr_Con_El : Elmt_Id;
4717 -- Set the designated type so it is available in case this is an access
4718 -- to a self-referential type, e.g. a standard list type with a next
4719 -- pointer. Will be reset after subtype is built.
4721 Set_Directly_Designated_Type
4722 (Derived_Type, Designated_Type (Parent_Type));
4724 Subt := Process_Subtype (S, N);
4726 if Nkind (S) /= N_Subtype_Indication
4727 and then Subt /= Base_Type (Subt)
4729 Set_Ekind (Derived_Type, E_Access_Subtype);
4732 if Ekind (Derived_Type) = E_Access_Subtype then
4734 Pbase : constant Entity_Id := Base_Type (Parent_Type);
4735 Ibase : constant Entity_Id :=
4736 Create_Itype (Ekind (Pbase), N, Derived_Type, 'B');
4737 Svg_Chars : constant Name_Id := Chars (Ibase);
4738 Svg_Next_E : constant Entity_Id := Next_Entity (Ibase);
4741 Copy_Node (Pbase, Ibase);
4743 Set_Chars (Ibase, Svg_Chars);
4744 Set_Next_Entity (Ibase, Svg_Next_E);
4745 Set_Sloc (Ibase, Sloc (Derived_Type));
4746 Set_Scope (Ibase, Scope (Derived_Type));
4747 Set_Freeze_Node (Ibase, Empty);
4748 Set_Is_Frozen (Ibase, False);
4749 Set_Comes_From_Source (Ibase, False);
4750 Set_Is_First_Subtype (Ibase, False);
4752 Set_Etype (Ibase, Pbase);
4753 Set_Etype (Derived_Type, Ibase);
4757 Set_Directly_Designated_Type
4758 (Derived_Type, Designated_Type (Subt));
4760 Set_Is_Constrained (Derived_Type, Is_Constrained (Subt));
4761 Set_Is_Access_Constant (Derived_Type, Is_Access_Constant (Parent_Type));
4762 Set_Size_Info (Derived_Type, Parent_Type);
4763 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
4764 Set_Depends_On_Private (Derived_Type,
4765 Has_Private_Component (Derived_Type));
4766 Conditional_Delay (Derived_Type, Subt);
4768 -- Ada 2005 (AI-231): Set the null-exclusion attribute, and verify
4769 -- that it is not redundant.
4771 if Null_Exclusion_Present (Type_Definition (N)) then
4772 Set_Can_Never_Be_Null (Derived_Type);
4774 if Can_Never_Be_Null (Parent_Type)
4778 ("`NOT NULL` not allowed (& already excludes null)",
4782 elsif Can_Never_Be_Null (Parent_Type) then
4783 Set_Can_Never_Be_Null (Derived_Type);
4786 -- Note: we do not copy the Storage_Size_Variable, since we always go to
4787 -- the root type for this information.
4789 -- Apply range checks to discriminants for derived record case
4790 -- ??? THIS CODE SHOULD NOT BE HERE REALLY.
4792 Desig_Type := Designated_Type (Derived_Type);
4793 if Is_Composite_Type (Desig_Type)
4794 and then (not Is_Array_Type (Desig_Type))
4795 and then Has_Discriminants (Desig_Type)
4796 and then Base_Type (Desig_Type) /= Desig_Type
4798 Discr_Con_Elist := Discriminant_Constraint (Desig_Type);
4799 Discr_Con_El := First_Elmt (Discr_Con_Elist);
4801 Discr := First_Discriminant (Base_Type (Desig_Type));
4802 while Present (Discr_Con_El) loop
4803 Apply_Range_Check (Node (Discr_Con_El), Etype (Discr));
4804 Next_Elmt (Discr_Con_El);
4805 Next_Discriminant (Discr);
4808 end Build_Derived_Access_Type;
4810 ------------------------------
4811 -- Build_Derived_Array_Type --
4812 ------------------------------
4814 procedure Build_Derived_Array_Type
4816 Parent_Type : Entity_Id;
4817 Derived_Type : Entity_Id)
4819 Loc : constant Source_Ptr := Sloc (N);
4820 Tdef : constant Node_Id := Type_Definition (N);
4821 Indic : constant Node_Id := Subtype_Indication (Tdef);
4822 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
4823 Implicit_Base : Entity_Id;
4824 New_Indic : Node_Id;
4826 procedure Make_Implicit_Base;
4827 -- If the parent subtype is constrained, the derived type is a subtype
4828 -- of an implicit base type derived from the parent base.
4830 ------------------------
4831 -- Make_Implicit_Base --
4832 ------------------------
4834 procedure Make_Implicit_Base is
4837 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
4839 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
4840 Set_Etype (Implicit_Base, Parent_Base);
4842 Copy_Array_Subtype_Attributes (Implicit_Base, Parent_Base);
4843 Copy_Array_Base_Type_Attributes (Implicit_Base, Parent_Base);
4845 Set_Has_Delayed_Freeze (Implicit_Base, True);
4846 end Make_Implicit_Base;
4848 -- Start of processing for Build_Derived_Array_Type
4851 if not Is_Constrained (Parent_Type) then
4852 if Nkind (Indic) /= N_Subtype_Indication then
4853 Set_Ekind (Derived_Type, E_Array_Type);
4855 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
4856 Copy_Array_Base_Type_Attributes (Derived_Type, Parent_Type);
4858 Set_Has_Delayed_Freeze (Derived_Type, True);
4862 Set_Etype (Derived_Type, Implicit_Base);
4865 Make_Subtype_Declaration (Loc,
4866 Defining_Identifier => Derived_Type,
4867 Subtype_Indication =>
4868 Make_Subtype_Indication (Loc,
4869 Subtype_Mark => New_Reference_To (Implicit_Base, Loc),
4870 Constraint => Constraint (Indic)));
4872 Rewrite (N, New_Indic);
4877 if Nkind (Indic) /= N_Subtype_Indication then
4880 Set_Ekind (Derived_Type, Ekind (Parent_Type));
4881 Set_Etype (Derived_Type, Implicit_Base);
4882 Copy_Array_Subtype_Attributes (Derived_Type, Parent_Type);
4885 Error_Msg_N ("illegal constraint on constrained type", Indic);
4889 -- If parent type is not a derived type itself, and is declared in
4890 -- closed scope (e.g. a subprogram), then we must explicitly introduce
4891 -- the new type's concatenation operator since Derive_Subprograms
4892 -- will not inherit the parent's operator. If the parent type is
4893 -- unconstrained, the operator is of the unconstrained base type.
4895 if Number_Dimensions (Parent_Type) = 1
4896 and then not Is_Limited_Type (Parent_Type)
4897 and then not Is_Derived_Type (Parent_Type)
4898 and then not Is_Package_Or_Generic_Package
4899 (Scope (Base_Type (Parent_Type)))
4901 if not Is_Constrained (Parent_Type)
4902 and then Is_Constrained (Derived_Type)
4904 New_Concatenation_Op (Implicit_Base);
4906 New_Concatenation_Op (Derived_Type);
4909 end Build_Derived_Array_Type;
4911 -----------------------------------
4912 -- Build_Derived_Concurrent_Type --
4913 -----------------------------------
4915 procedure Build_Derived_Concurrent_Type
4917 Parent_Type : Entity_Id;
4918 Derived_Type : Entity_Id)
4920 Loc : constant Source_Ptr := Sloc (N);
4922 Corr_Record : constant Entity_Id :=
4923 Make_Defining_Identifier (Loc, New_Internal_Name ('C'));
4925 Corr_Decl : Node_Id;
4926 Corr_Decl_Needed : Boolean;
4927 -- If the derived type has fewer discriminants than its parent, the
4928 -- corresponding record is also a derived type, in order to account for
4929 -- the bound discriminants. We create a full type declaration for it in
4932 Constraint_Present : constant Boolean :=
4933 Nkind (Subtype_Indication (Type_Definition (N))) =
4934 N_Subtype_Indication;
4936 D_Constraint : Node_Id;
4937 New_Constraint : Elist_Id;
4938 Old_Disc : Entity_Id;
4939 New_Disc : Entity_Id;
4943 Set_Stored_Constraint (Derived_Type, No_Elist);
4944 Corr_Decl_Needed := False;
4947 if Present (Discriminant_Specifications (N))
4948 and then Constraint_Present
4950 Old_Disc := First_Discriminant (Parent_Type);
4951 New_Disc := First (Discriminant_Specifications (N));
4952 while Present (New_Disc) and then Present (Old_Disc) loop
4953 Next_Discriminant (Old_Disc);
4958 if Present (Old_Disc) then
4960 -- The new type has fewer discriminants, so we need to create a new
4961 -- corresponding record, which is derived from the corresponding
4962 -- record of the parent, and has a stored constraint that captures
4963 -- the values of the discriminant constraints.
4965 -- The type declaration for the derived corresponding record has
4966 -- the same discriminant part and constraints as the current
4967 -- declaration. Copy the unanalyzed tree to build declaration.
4969 Corr_Decl_Needed := True;
4970 New_N := Copy_Separate_Tree (N);
4973 Make_Full_Type_Declaration (Loc,
4974 Defining_Identifier => Corr_Record,
4975 Discriminant_Specifications =>
4976 Discriminant_Specifications (New_N),
4978 Make_Derived_Type_Definition (Loc,
4979 Subtype_Indication =>
4980 Make_Subtype_Indication (Loc,
4983 (Corresponding_Record_Type (Parent_Type), Loc),
4986 (Subtype_Indication (Type_Definition (New_N))))));
4989 -- Copy Storage_Size and Relative_Deadline variables if task case
4991 if Is_Task_Type (Parent_Type) then
4992 Set_Storage_Size_Variable (Derived_Type,
4993 Storage_Size_Variable (Parent_Type));
4994 Set_Relative_Deadline_Variable (Derived_Type,
4995 Relative_Deadline_Variable (Parent_Type));
4998 if Present (Discriminant_Specifications (N)) then
4999 Push_Scope (Derived_Type);
5000 Check_Or_Process_Discriminants (N, Derived_Type);
5002 if Constraint_Present then
5004 Expand_To_Stored_Constraint
5006 Build_Discriminant_Constraints
5008 Subtype_Indication (Type_Definition (N)), True));
5013 elsif Constraint_Present then
5015 -- Build constrained subtype and derive from it
5018 Loc : constant Source_Ptr := Sloc (N);
5019 Anon : constant Entity_Id :=
5020 Make_Defining_Identifier (Loc,
5021 New_External_Name (Chars (Derived_Type), 'T'));
5026 Make_Subtype_Declaration (Loc,
5027 Defining_Identifier => Anon,
5028 Subtype_Indication =>
5029 Subtype_Indication (Type_Definition (N)));
5030 Insert_Before (N, Decl);
5033 Rewrite (Subtype_Indication (Type_Definition (N)),
5034 New_Occurrence_Of (Anon, Loc));
5035 Set_Analyzed (Derived_Type, False);
5041 -- By default, operations and private data are inherited from parent.
5042 -- However, in the presence of bound discriminants, a new corresponding
5043 -- record will be created, see below.
5045 Set_Has_Discriminants
5046 (Derived_Type, Has_Discriminants (Parent_Type));
5047 Set_Corresponding_Record_Type
5048 (Derived_Type, Corresponding_Record_Type (Parent_Type));
5050 -- Is_Constrained is set according the parent subtype, but is set to
5051 -- False if the derived type is declared with new discriminants.
5055 (Is_Constrained (Parent_Type) or else Constraint_Present)
5056 and then not Present (Discriminant_Specifications (N)));
5058 if Constraint_Present then
5059 if not Has_Discriminants (Parent_Type) then
5060 Error_Msg_N ("untagged parent must have discriminants", N);
5062 elsif Present (Discriminant_Specifications (N)) then
5064 -- Verify that new discriminants are used to constrain old ones
5069 (Constraint (Subtype_Indication (Type_Definition (N)))));
5071 Old_Disc := First_Discriminant (Parent_Type);
5073 while Present (D_Constraint) loop
5074 if Nkind (D_Constraint) /= N_Discriminant_Association then
5076 -- Positional constraint. If it is a reference to a new
5077 -- discriminant, it constrains the corresponding old one.
5079 if Nkind (D_Constraint) = N_Identifier then
5080 New_Disc := First_Discriminant (Derived_Type);
5081 while Present (New_Disc) loop
5082 exit when Chars (New_Disc) = Chars (D_Constraint);
5083 Next_Discriminant (New_Disc);
5086 if Present (New_Disc) then
5087 Set_Corresponding_Discriminant (New_Disc, Old_Disc);
5091 Next_Discriminant (Old_Disc);
5093 -- if this is a named constraint, search by name for the old
5094 -- discriminants constrained by the new one.
5096 elsif Nkind (Expression (D_Constraint)) = N_Identifier then
5098 -- Find new discriminant with that name
5100 New_Disc := First_Discriminant (Derived_Type);
5101 while Present (New_Disc) loop
5103 Chars (New_Disc) = Chars (Expression (D_Constraint));
5104 Next_Discriminant (New_Disc);
5107 if Present (New_Disc) then
5109 -- Verify that new discriminant renames some discriminant
5110 -- of the parent type, and associate the new discriminant
5111 -- with one or more old ones that it renames.
5117 Selector := First (Selector_Names (D_Constraint));
5118 while Present (Selector) loop
5119 Old_Disc := First_Discriminant (Parent_Type);
5120 while Present (Old_Disc) loop
5121 exit when Chars (Old_Disc) = Chars (Selector);
5122 Next_Discriminant (Old_Disc);
5125 if Present (Old_Disc) then
5126 Set_Corresponding_Discriminant
5127 (New_Disc, Old_Disc);
5136 Next (D_Constraint);
5139 New_Disc := First_Discriminant (Derived_Type);
5140 while Present (New_Disc) loop
5141 if No (Corresponding_Discriminant (New_Disc)) then
5143 ("new discriminant& must constrain old one", N, New_Disc);
5146 Subtypes_Statically_Compatible
5148 Etype (Corresponding_Discriminant (New_Disc)))
5151 ("& not statically compatible with parent discriminant",
5155 Next_Discriminant (New_Disc);
5159 elsif Present (Discriminant_Specifications (N)) then
5161 ("missing discriminant constraint in untagged derivation", N);
5164 -- The entity chain of the derived type includes the new discriminants
5165 -- but shares operations with the parent.
5167 if Present (Discriminant_Specifications (N)) then
5168 Old_Disc := First_Discriminant (Parent_Type);
5169 while Present (Old_Disc) loop
5170 if No (Next_Entity (Old_Disc))
5171 or else Ekind (Next_Entity (Old_Disc)) /= E_Discriminant
5174 (Last_Entity (Derived_Type), Next_Entity (Old_Disc));
5178 Next_Discriminant (Old_Disc);
5182 Set_First_Entity (Derived_Type, First_Entity (Parent_Type));
5183 if Has_Discriminants (Parent_Type) then
5184 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5185 Set_Discriminant_Constraint (
5186 Derived_Type, Discriminant_Constraint (Parent_Type));
5190 Set_Last_Entity (Derived_Type, Last_Entity (Parent_Type));
5192 Set_Has_Completion (Derived_Type);
5194 if Corr_Decl_Needed then
5195 Set_Stored_Constraint (Derived_Type, New_Constraint);
5196 Insert_After (N, Corr_Decl);
5197 Analyze (Corr_Decl);
5198 Set_Corresponding_Record_Type (Derived_Type, Corr_Record);
5200 end Build_Derived_Concurrent_Type;
5202 ------------------------------------
5203 -- Build_Derived_Enumeration_Type --
5204 ------------------------------------
5206 procedure Build_Derived_Enumeration_Type
5208 Parent_Type : Entity_Id;
5209 Derived_Type : Entity_Id)
5211 Loc : constant Source_Ptr := Sloc (N);
5212 Def : constant Node_Id := Type_Definition (N);
5213 Indic : constant Node_Id := Subtype_Indication (Def);
5214 Implicit_Base : Entity_Id;
5215 Literal : Entity_Id;
5216 New_Lit : Entity_Id;
5217 Literals_List : List_Id;
5218 Type_Decl : Node_Id;
5220 Rang_Expr : Node_Id;
5223 -- Since types Standard.Character and Standard.[Wide_]Wide_Character do
5224 -- not have explicit literals lists we need to process types derived
5225 -- from them specially. This is handled by Derived_Standard_Character.
5226 -- If the parent type is a generic type, there are no literals either,
5227 -- and we construct the same skeletal representation as for the generic
5230 if Is_Standard_Character_Type (Parent_Type) then
5231 Derived_Standard_Character (N, Parent_Type, Derived_Type);
5233 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
5239 if Nkind (Indic) /= N_Subtype_Indication then
5241 Make_Attribute_Reference (Loc,
5242 Attribute_Name => Name_First,
5243 Prefix => New_Reference_To (Derived_Type, Loc));
5244 Set_Etype (Lo, Derived_Type);
5247 Make_Attribute_Reference (Loc,
5248 Attribute_Name => Name_Last,
5249 Prefix => New_Reference_To (Derived_Type, Loc));
5250 Set_Etype (Hi, Derived_Type);
5252 Set_Scalar_Range (Derived_Type,
5258 -- Analyze subtype indication and verify compatibility
5259 -- with parent type.
5261 if Base_Type (Process_Subtype (Indic, N)) /=
5262 Base_Type (Parent_Type)
5265 ("illegal constraint for formal discrete type", N);
5271 -- If a constraint is present, analyze the bounds to catch
5272 -- premature usage of the derived literals.
5274 if Nkind (Indic) = N_Subtype_Indication
5275 and then Nkind (Range_Expression (Constraint (Indic))) = N_Range
5277 Analyze (Low_Bound (Range_Expression (Constraint (Indic))));
5278 Analyze (High_Bound (Range_Expression (Constraint (Indic))));
5281 -- Introduce an implicit base type for the derived type even if there
5282 -- is no constraint attached to it, since this seems closer to the
5283 -- Ada semantics. Build a full type declaration tree for the derived
5284 -- type using the implicit base type as the defining identifier. The
5285 -- build a subtype declaration tree which applies the constraint (if
5286 -- any) have it replace the derived type declaration.
5288 Literal := First_Literal (Parent_Type);
5289 Literals_List := New_List;
5290 while Present (Literal)
5291 and then Ekind (Literal) = E_Enumeration_Literal
5293 -- Literals of the derived type have the same representation as
5294 -- those of the parent type, but this representation can be
5295 -- overridden by an explicit representation clause. Indicate
5296 -- that there is no explicit representation given yet. These
5297 -- derived literals are implicit operations of the new type,
5298 -- and can be overridden by explicit ones.
5300 if Nkind (Literal) = N_Defining_Character_Literal then
5302 Make_Defining_Character_Literal (Loc, Chars (Literal));
5304 New_Lit := Make_Defining_Identifier (Loc, Chars (Literal));
5307 Set_Ekind (New_Lit, E_Enumeration_Literal);
5308 Set_Enumeration_Pos (New_Lit, Enumeration_Pos (Literal));
5309 Set_Enumeration_Rep (New_Lit, Enumeration_Rep (Literal));
5310 Set_Enumeration_Rep_Expr (New_Lit, Empty);
5311 Set_Alias (New_Lit, Literal);
5312 Set_Is_Known_Valid (New_Lit, True);
5314 Append (New_Lit, Literals_List);
5315 Next_Literal (Literal);
5319 Make_Defining_Identifier (Sloc (Derived_Type),
5320 New_External_Name (Chars (Derived_Type), 'B'));
5322 -- Indicate the proper nature of the derived type. This must be done
5323 -- before analysis of the literals, to recognize cases when a literal
5324 -- may be hidden by a previous explicit function definition (cf.
5327 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
5328 Set_Etype (Derived_Type, Implicit_Base);
5331 Make_Full_Type_Declaration (Loc,
5332 Defining_Identifier => Implicit_Base,
5333 Discriminant_Specifications => No_List,
5335 Make_Enumeration_Type_Definition (Loc, Literals_List));
5337 Mark_Rewrite_Insertion (Type_Decl);
5338 Insert_Before (N, Type_Decl);
5339 Analyze (Type_Decl);
5341 -- After the implicit base is analyzed its Etype needs to be changed
5342 -- to reflect the fact that it is derived from the parent type which
5343 -- was ignored during analysis. We also set the size at this point.
5345 Set_Etype (Implicit_Base, Parent_Type);
5347 Set_Size_Info (Implicit_Base, Parent_Type);
5348 Set_RM_Size (Implicit_Base, RM_Size (Parent_Type));
5349 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Type));
5351 Set_Has_Non_Standard_Rep
5352 (Implicit_Base, Has_Non_Standard_Rep
5354 Set_Has_Delayed_Freeze (Implicit_Base);
5356 -- Process the subtype indication including a validation check on the
5357 -- constraint, if any. If a constraint is given, its bounds must be
5358 -- implicitly converted to the new type.
5360 if Nkind (Indic) = N_Subtype_Indication then
5362 R : constant Node_Id :=
5363 Range_Expression (Constraint (Indic));
5366 if Nkind (R) = N_Range then
5367 Hi := Build_Scalar_Bound
5368 (High_Bound (R), Parent_Type, Implicit_Base);
5369 Lo := Build_Scalar_Bound
5370 (Low_Bound (R), Parent_Type, Implicit_Base);
5373 -- Constraint is a Range attribute. Replace with explicit
5374 -- mention of the bounds of the prefix, which must be a
5377 Analyze (Prefix (R));
5379 Convert_To (Implicit_Base,
5380 Make_Attribute_Reference (Loc,
5381 Attribute_Name => Name_Last,
5383 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
5386 Convert_To (Implicit_Base,
5387 Make_Attribute_Reference (Loc,
5388 Attribute_Name => Name_First,
5390 New_Occurrence_Of (Entity (Prefix (R)), Loc)));
5397 (Type_High_Bound (Parent_Type),
5398 Parent_Type, Implicit_Base);
5401 (Type_Low_Bound (Parent_Type),
5402 Parent_Type, Implicit_Base);
5410 -- If we constructed a default range for the case where no range
5411 -- was given, then the expressions in the range must not freeze
5412 -- since they do not correspond to expressions in the source.
5414 if Nkind (Indic) /= N_Subtype_Indication then
5415 Set_Must_Not_Freeze (Lo);
5416 Set_Must_Not_Freeze (Hi);
5417 Set_Must_Not_Freeze (Rang_Expr);
5421 Make_Subtype_Declaration (Loc,
5422 Defining_Identifier => Derived_Type,
5423 Subtype_Indication =>
5424 Make_Subtype_Indication (Loc,
5425 Subtype_Mark => New_Occurrence_Of (Implicit_Base, Loc),
5427 Make_Range_Constraint (Loc,
5428 Range_Expression => Rang_Expr))));
5432 -- If pragma Discard_Names applies on the first subtype of the parent
5433 -- type, then it must be applied on this subtype as well.
5435 if Einfo.Discard_Names (First_Subtype (Parent_Type)) then
5436 Set_Discard_Names (Derived_Type);
5439 -- Apply a range check. Since this range expression doesn't have an
5440 -- Etype, we have to specifically pass the Source_Typ parameter. Is
5443 if Nkind (Indic) = N_Subtype_Indication then
5444 Apply_Range_Check (Range_Expression (Constraint (Indic)),
5446 Source_Typ => Entity (Subtype_Mark (Indic)));
5449 end Build_Derived_Enumeration_Type;
5451 --------------------------------
5452 -- Build_Derived_Numeric_Type --
5453 --------------------------------
5455 procedure Build_Derived_Numeric_Type
5457 Parent_Type : Entity_Id;
5458 Derived_Type : Entity_Id)
5460 Loc : constant Source_Ptr := Sloc (N);
5461 Tdef : constant Node_Id := Type_Definition (N);
5462 Indic : constant Node_Id := Subtype_Indication (Tdef);
5463 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
5464 No_Constraint : constant Boolean := Nkind (Indic) /=
5465 N_Subtype_Indication;
5466 Implicit_Base : Entity_Id;
5472 -- Process the subtype indication including a validation check on
5473 -- the constraint if any.
5475 Discard_Node (Process_Subtype (Indic, N));
5477 -- Introduce an implicit base type for the derived type even if there
5478 -- is no constraint attached to it, since this seems closer to the Ada
5482 Create_Itype (Ekind (Parent_Base), N, Derived_Type, 'B');
5484 Set_Etype (Implicit_Base, Parent_Base);
5485 Set_Ekind (Implicit_Base, Ekind (Parent_Base));
5486 Set_Size_Info (Implicit_Base, Parent_Base);
5487 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Parent_Base));
5488 Set_Parent (Implicit_Base, Parent (Derived_Type));
5489 Set_Is_Known_Valid (Implicit_Base, Is_Known_Valid (Parent_Base));
5491 -- Set RM Size for discrete type or decimal fixed-point type
5492 -- Ordinary fixed-point is excluded, why???
5494 if Is_Discrete_Type (Parent_Base)
5495 or else Is_Decimal_Fixed_Point_Type (Parent_Base)
5497 Set_RM_Size (Implicit_Base, RM_Size (Parent_Base));
5500 Set_Has_Delayed_Freeze (Implicit_Base);
5502 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
5503 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
5505 Set_Scalar_Range (Implicit_Base,
5510 if Has_Infinities (Parent_Base) then
5511 Set_Includes_Infinities (Scalar_Range (Implicit_Base));
5514 -- The Derived_Type, which is the entity of the declaration, is a
5515 -- subtype of the implicit base. Its Ekind is a subtype, even in the
5516 -- absence of an explicit constraint.
5518 Set_Etype (Derived_Type, Implicit_Base);
5520 -- If we did not have a constraint, then the Ekind is set from the
5521 -- parent type (otherwise Process_Subtype has set the bounds)
5523 if No_Constraint then
5524 Set_Ekind (Derived_Type, Subtype_Kind (Ekind (Parent_Type)));
5527 -- If we did not have a range constraint, then set the range from the
5528 -- parent type. Otherwise, the call to Process_Subtype has set the
5532 or else not Has_Range_Constraint (Indic)
5534 Set_Scalar_Range (Derived_Type,
5536 Low_Bound => New_Copy_Tree (Type_Low_Bound (Parent_Type)),
5537 High_Bound => New_Copy_Tree (Type_High_Bound (Parent_Type))));
5538 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
5540 if Has_Infinities (Parent_Type) then
5541 Set_Includes_Infinities (Scalar_Range (Derived_Type));
5544 Set_Is_Known_Valid (Derived_Type, Is_Known_Valid (Parent_Type));
5547 Set_Is_Descendent_Of_Address (Derived_Type,
5548 Is_Descendent_Of_Address (Parent_Type));
5549 Set_Is_Descendent_Of_Address (Implicit_Base,
5550 Is_Descendent_Of_Address (Parent_Type));
5552 -- Set remaining type-specific fields, depending on numeric type
5554 if Is_Modular_Integer_Type (Parent_Type) then
5555 Set_Modulus (Implicit_Base, Modulus (Parent_Base));
5557 Set_Non_Binary_Modulus
5558 (Implicit_Base, Non_Binary_Modulus (Parent_Base));
5561 (Implicit_Base, Is_Known_Valid (Parent_Base));
5563 elsif Is_Floating_Point_Type (Parent_Type) then
5565 -- Digits of base type is always copied from the digits value of
5566 -- the parent base type, but the digits of the derived type will
5567 -- already have been set if there was a constraint present.
5569 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
5570 Set_Vax_Float (Implicit_Base, Vax_Float (Parent_Base));
5572 if No_Constraint then
5573 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Type));
5576 elsif Is_Fixed_Point_Type (Parent_Type) then
5578 -- Small of base type and derived type are always copied from the
5579 -- parent base type, since smalls never change. The delta of the
5580 -- base type is also copied from the parent base type. However the
5581 -- delta of the derived type will have been set already if a
5582 -- constraint was present.
5584 Set_Small_Value (Derived_Type, Small_Value (Parent_Base));
5585 Set_Small_Value (Implicit_Base, Small_Value (Parent_Base));
5586 Set_Delta_Value (Implicit_Base, Delta_Value (Parent_Base));
5588 if No_Constraint then
5589 Set_Delta_Value (Derived_Type, Delta_Value (Parent_Type));
5592 -- The scale and machine radix in the decimal case are always
5593 -- copied from the parent base type.
5595 if Is_Decimal_Fixed_Point_Type (Parent_Type) then
5596 Set_Scale_Value (Derived_Type, Scale_Value (Parent_Base));
5597 Set_Scale_Value (Implicit_Base, Scale_Value (Parent_Base));
5599 Set_Machine_Radix_10
5600 (Derived_Type, Machine_Radix_10 (Parent_Base));
5601 Set_Machine_Radix_10
5602 (Implicit_Base, Machine_Radix_10 (Parent_Base));
5604 Set_Digits_Value (Implicit_Base, Digits_Value (Parent_Base));
5606 if No_Constraint then
5607 Set_Digits_Value (Derived_Type, Digits_Value (Parent_Base));
5610 -- the analysis of the subtype_indication sets the
5611 -- digits value of the derived type.
5618 -- The type of the bounds is that of the parent type, and they
5619 -- must be converted to the derived type.
5621 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
5623 -- The implicit_base should be frozen when the derived type is frozen,
5624 -- but note that it is used in the conversions of the bounds. For fixed
5625 -- types we delay the determination of the bounds until the proper
5626 -- freezing point. For other numeric types this is rejected by GCC, for
5627 -- reasons that are currently unclear (???), so we choose to freeze the
5628 -- implicit base now. In the case of integers and floating point types
5629 -- this is harmless because subsequent representation clauses cannot
5630 -- affect anything, but it is still baffling that we cannot use the
5631 -- same mechanism for all derived numeric types.
5633 -- There is a further complication: actually *some* representation
5634 -- clauses can affect the implicit base type. Namely, attribute
5635 -- definition clauses for stream-oriented attributes need to set the
5636 -- corresponding TSS entries on the base type, and this normally cannot
5637 -- be done after the base type is frozen, so the circuitry in
5638 -- Sem_Ch13.New_Stream_Subprogram must account for this possibility and
5639 -- not use Set_TSS in this case.
5641 if Is_Fixed_Point_Type (Parent_Type) then
5642 Conditional_Delay (Implicit_Base, Parent_Type);
5644 Freeze_Before (N, Implicit_Base);
5646 end Build_Derived_Numeric_Type;
5648 --------------------------------
5649 -- Build_Derived_Private_Type --
5650 --------------------------------
5652 procedure Build_Derived_Private_Type
5654 Parent_Type : Entity_Id;
5655 Derived_Type : Entity_Id;
5656 Is_Completion : Boolean;
5657 Derive_Subps : Boolean := True)
5659 Loc : constant Source_Ptr := Sloc (N);
5660 Der_Base : Entity_Id;
5662 Full_Decl : Node_Id := Empty;
5663 Full_Der : Entity_Id;
5665 Last_Discr : Entity_Id;
5666 Par_Scope : constant Entity_Id := Scope (Base_Type (Parent_Type));
5667 Swapped : Boolean := False;
5669 procedure Copy_And_Build;
5670 -- Copy derived type declaration, replace parent with its full view,
5671 -- and analyze new declaration.
5673 --------------------
5674 -- Copy_And_Build --
5675 --------------------
5677 procedure Copy_And_Build is
5681 if Ekind (Parent_Type) in Record_Kind
5683 (Ekind (Parent_Type) in Enumeration_Kind
5684 and then not Is_Standard_Character_Type (Parent_Type)
5685 and then not Is_Generic_Type (Root_Type (Parent_Type)))
5687 Full_N := New_Copy_Tree (N);
5688 Insert_After (N, Full_N);
5689 Build_Derived_Type (
5690 Full_N, Parent_Type, Full_Der, True, Derive_Subps => False);
5693 Build_Derived_Type (
5694 N, Parent_Type, Full_Der, True, Derive_Subps => False);
5698 -- Start of processing for Build_Derived_Private_Type
5701 if Is_Tagged_Type (Parent_Type) then
5702 Full_P := Full_View (Parent_Type);
5704 -- A type extension of a type with unknown discriminants is an
5705 -- indefinite type that the back-end cannot handle directly.
5706 -- We treat it as a private type, and build a completion that is
5707 -- derived from the full view of the parent, and hopefully has
5708 -- known discriminants.
5710 -- If the full view of the parent type has an underlying record view,
5711 -- use it to generate the underlying record view of this derived type
5712 -- (required for chains of derivations with unknown discriminants).
5714 -- Minor optimization: we avoid the generation of useless underlying
5715 -- record view entities if the private type declaration has unknown
5716 -- discriminants but its corresponding full view has no
5719 if Has_Unknown_Discriminants (Parent_Type)
5720 and then Present (Full_P)
5721 and then (Has_Discriminants (Full_P)
5722 or else Present (Underlying_Record_View (Full_P)))
5723 and then not In_Open_Scopes (Par_Scope)
5724 and then Expander_Active
5727 Full_Der : constant Entity_Id :=
5728 Make_Defining_Identifier (Loc,
5729 Chars => New_Internal_Name ('T'));
5730 New_Ext : constant Node_Id :=
5732 (Record_Extension_Part (Type_Definition (N)));
5736 Build_Derived_Record_Type
5737 (N, Parent_Type, Derived_Type, Derive_Subps);
5739 -- Build anonymous completion, as a derivation from the full
5740 -- view of the parent. This is not a completion in the usual
5741 -- sense, because the current type is not private.
5744 Make_Full_Type_Declaration (Loc,
5745 Defining_Identifier => Full_Der,
5747 Make_Derived_Type_Definition (Loc,
5748 Subtype_Indication =>
5750 (Subtype_Indication (Type_Definition (N))),
5751 Record_Extension_Part => New_Ext));
5753 -- If the parent type has an underlying record view, use it
5754 -- here to build the new underlying record view.
5756 if Present (Underlying_Record_View (Full_P)) then
5758 (Nkind (Subtype_Indication (Type_Definition (Decl)))
5760 Set_Entity (Subtype_Indication (Type_Definition (Decl)),
5761 Underlying_Record_View (Full_P));
5764 Install_Private_Declarations (Par_Scope);
5765 Install_Visible_Declarations (Par_Scope);
5766 Insert_Before (N, Decl);
5768 -- Mark entity as an underlying record view before analysis,
5769 -- to avoid generating the list of its primitive operations
5770 -- (which is not really required for this entity) and thus
5771 -- prevent spurious errors associated with missing overriding
5772 -- of abstract primitives (overridden only for Derived_Type).
5774 Set_Ekind (Full_Der, E_Record_Type);
5775 Set_Is_Underlying_Record_View (Full_Der);
5779 pragma Assert (Has_Discriminants (Full_Der)
5780 and then not Has_Unknown_Discriminants (Full_Der));
5782 Uninstall_Declarations (Par_Scope);
5784 -- Freeze the underlying record view, to prevent generation of
5785 -- useless dispatching information, which is simply shared with
5786 -- the real derived type.
5788 Set_Is_Frozen (Full_Der);
5790 -- Set up links between real entity and underlying record view
5792 Set_Underlying_Record_View (Derived_Type, Base_Type (Full_Der));
5793 Set_Underlying_Record_View (Base_Type (Full_Der), Derived_Type);
5796 -- If discriminants are known, build derived record
5799 Build_Derived_Record_Type
5800 (N, Parent_Type, Derived_Type, Derive_Subps);
5805 elsif Has_Discriminants (Parent_Type) then
5806 if Present (Full_View (Parent_Type)) then
5807 if not Is_Completion then
5809 -- Copy declaration for subsequent analysis, to provide a
5810 -- completion for what is a private declaration. Indicate that
5811 -- the full type is internally generated.
5813 Full_Decl := New_Copy_Tree (N);
5814 Full_Der := New_Copy (Derived_Type);
5815 Set_Comes_From_Source (Full_Decl, False);
5816 Set_Comes_From_Source (Full_Der, False);
5818 Insert_After (N, Full_Decl);
5821 -- If this is a completion, the full view being built is itself
5822 -- private. We build a subtype of the parent with the same
5823 -- constraints as this full view, to convey to the back end the
5824 -- constrained components and the size of this subtype. If the
5825 -- parent is constrained, its full view can serve as the
5826 -- underlying full view of the derived type.
5828 if No (Discriminant_Specifications (N)) then
5829 if Nkind (Subtype_Indication (Type_Definition (N))) =
5830 N_Subtype_Indication
5832 Build_Underlying_Full_View (N, Derived_Type, Parent_Type);
5834 elsif Is_Constrained (Full_View (Parent_Type)) then
5835 Set_Underlying_Full_View
5836 (Derived_Type, Full_View (Parent_Type));
5840 -- If there are new discriminants, the parent subtype is
5841 -- constrained by them, but it is not clear how to build
5842 -- the Underlying_Full_View in this case???
5849 -- Build partial view of derived type from partial view of parent
5851 Build_Derived_Record_Type
5852 (N, Parent_Type, Derived_Type, Derive_Subps);
5854 if Present (Full_View (Parent_Type)) and then not Is_Completion then
5855 if not In_Open_Scopes (Par_Scope)
5856 or else not In_Same_Source_Unit (N, Parent_Type)
5858 -- Swap partial and full views temporarily
5860 Install_Private_Declarations (Par_Scope);
5861 Install_Visible_Declarations (Par_Scope);
5865 -- Build full view of derived type from full view of parent which
5866 -- is now installed. Subprograms have been derived on the partial
5867 -- view, the completion does not derive them anew.
5869 if not Is_Tagged_Type (Parent_Type) then
5871 -- If the parent is itself derived from another private type,
5872 -- installing the private declarations has not affected its
5873 -- privacy status, so use its own full view explicitly.
5875 if Is_Private_Type (Parent_Type) then
5876 Build_Derived_Record_Type
5877 (Full_Decl, Full_View (Parent_Type), Full_Der, False);
5879 Build_Derived_Record_Type
5880 (Full_Decl, Parent_Type, Full_Der, False);
5884 -- If full view of parent is tagged, the completion inherits
5885 -- the proper primitive operations.
5887 Set_Defining_Identifier (Full_Decl, Full_Der);
5888 Build_Derived_Record_Type
5889 (Full_Decl, Parent_Type, Full_Der, Derive_Subps);
5890 Set_Analyzed (Full_Decl);
5894 Uninstall_Declarations (Par_Scope);
5896 if In_Open_Scopes (Par_Scope) then
5897 Install_Visible_Declarations (Par_Scope);
5901 Der_Base := Base_Type (Derived_Type);
5902 Set_Full_View (Derived_Type, Full_Der);
5903 Set_Full_View (Der_Base, Base_Type (Full_Der));
5905 -- Copy the discriminant list from full view to the partial views
5906 -- (base type and its subtype). Gigi requires that the partial and
5907 -- full views have the same discriminants.
5909 -- Note that since the partial view is pointing to discriminants
5910 -- in the full view, their scope will be that of the full view.
5911 -- This might cause some front end problems and need adjustment???
5913 Discr := First_Discriminant (Base_Type (Full_Der));
5914 Set_First_Entity (Der_Base, Discr);
5917 Last_Discr := Discr;
5918 Next_Discriminant (Discr);
5919 exit when No (Discr);
5922 Set_Last_Entity (Der_Base, Last_Discr);
5924 Set_First_Entity (Derived_Type, First_Entity (Der_Base));
5925 Set_Last_Entity (Derived_Type, Last_Entity (Der_Base));
5926 Set_Stored_Constraint (Full_Der, Stored_Constraint (Derived_Type));
5929 -- If this is a completion, the derived type stays private and
5930 -- there is no need to create a further full view, except in the
5931 -- unusual case when the derivation is nested within a child unit,
5937 elsif Present (Full_View (Parent_Type))
5938 and then Has_Discriminants (Full_View (Parent_Type))
5940 if Has_Unknown_Discriminants (Parent_Type)
5941 and then Nkind (Subtype_Indication (Type_Definition (N))) =
5942 N_Subtype_Indication
5945 ("cannot constrain type with unknown discriminants",
5946 Subtype_Indication (Type_Definition (N)));
5950 -- If full view of parent is a record type, build full view as a
5951 -- derivation from the parent's full view. Partial view remains
5952 -- private. For code generation and linking, the full view must have
5953 -- the same public status as the partial one. This full view is only
5954 -- needed if the parent type is in an enclosing scope, so that the
5955 -- full view may actually become visible, e.g. in a child unit. This
5956 -- is both more efficient, and avoids order of freezing problems with
5957 -- the added entities.
5959 if not Is_Private_Type (Full_View (Parent_Type))
5960 and then (In_Open_Scopes (Scope (Parent_Type)))
5962 Full_Der := Make_Defining_Identifier (Sloc (Derived_Type),
5963 Chars (Derived_Type));
5964 Set_Is_Itype (Full_Der);
5965 Set_Has_Private_Declaration (Full_Der);
5966 Set_Has_Private_Declaration (Derived_Type);
5967 Set_Associated_Node_For_Itype (Full_Der, N);
5968 Set_Parent (Full_Der, Parent (Derived_Type));
5969 Set_Full_View (Derived_Type, Full_Der);
5970 Set_Is_Public (Full_Der, Is_Public (Derived_Type));
5971 Full_P := Full_View (Parent_Type);
5972 Exchange_Declarations (Parent_Type);
5974 Exchange_Declarations (Full_P);
5977 Build_Derived_Record_Type
5978 (N, Full_View (Parent_Type), Derived_Type,
5979 Derive_Subps => False);
5982 -- In any case, the primitive operations are inherited from the
5983 -- parent type, not from the internal full view.
5985 Set_Etype (Base_Type (Derived_Type), Base_Type (Parent_Type));
5987 if Derive_Subps then
5988 Derive_Subprograms (Parent_Type, Derived_Type);
5992 -- Untagged type, No discriminants on either view
5994 if Nkind (Subtype_Indication (Type_Definition (N))) =
5995 N_Subtype_Indication
5998 ("illegal constraint on type without discriminants", N);
6001 if Present (Discriminant_Specifications (N))
6002 and then Present (Full_View (Parent_Type))
6003 and then not Is_Tagged_Type (Full_View (Parent_Type))
6005 Error_Msg_N ("cannot add discriminants to untagged type", N);
6008 Set_Stored_Constraint (Derived_Type, No_Elist);
6009 Set_Is_Constrained (Derived_Type, Is_Constrained (Parent_Type));
6010 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
6011 Set_Has_Controlled_Component
6012 (Derived_Type, Has_Controlled_Component
6015 -- Direct controlled types do not inherit Finalize_Storage_Only flag
6017 if not Is_Controlled (Parent_Type) then
6018 Set_Finalize_Storage_Only
6019 (Base_Type (Derived_Type), Finalize_Storage_Only (Parent_Type));
6022 -- Construct the implicit full view by deriving from full view of the
6023 -- parent type. In order to get proper visibility, we install the
6024 -- parent scope and its declarations.
6026 -- ??? If the parent is untagged private and its completion is
6027 -- tagged, this mechanism will not work because we cannot derive from
6028 -- the tagged full view unless we have an extension.
6030 if Present (Full_View (Parent_Type))
6031 and then not Is_Tagged_Type (Full_View (Parent_Type))
6032 and then not Is_Completion
6035 Make_Defining_Identifier (Sloc (Derived_Type),
6036 Chars => Chars (Derived_Type));
6037 Set_Is_Itype (Full_Der);
6038 Set_Has_Private_Declaration (Full_Der);
6039 Set_Has_Private_Declaration (Derived_Type);
6040 Set_Associated_Node_For_Itype (Full_Der, N);
6041 Set_Parent (Full_Der, Parent (Derived_Type));
6042 Set_Full_View (Derived_Type, Full_Der);
6044 if not In_Open_Scopes (Par_Scope) then
6045 Install_Private_Declarations (Par_Scope);
6046 Install_Visible_Declarations (Par_Scope);
6048 Uninstall_Declarations (Par_Scope);
6050 -- If parent scope is open and in another unit, and parent has a
6051 -- completion, then the derivation is taking place in the visible
6052 -- part of a child unit. In that case retrieve the full view of
6053 -- the parent momentarily.
6055 elsif not In_Same_Source_Unit (N, Parent_Type) then
6056 Full_P := Full_View (Parent_Type);
6057 Exchange_Declarations (Parent_Type);
6059 Exchange_Declarations (Full_P);
6061 -- Otherwise it is a local derivation
6067 Set_Scope (Full_Der, Current_Scope);
6068 Set_Is_First_Subtype (Full_Der,
6069 Is_First_Subtype (Derived_Type));
6070 Set_Has_Size_Clause (Full_Der, False);
6071 Set_Has_Alignment_Clause (Full_Der, False);
6072 Set_Next_Entity (Full_Der, Empty);
6073 Set_Has_Delayed_Freeze (Full_Der);
6074 Set_Is_Frozen (Full_Der, False);
6075 Set_Freeze_Node (Full_Der, Empty);
6076 Set_Depends_On_Private (Full_Der,
6077 Has_Private_Component (Full_Der));
6078 Set_Public_Status (Full_Der);
6082 Set_Has_Unknown_Discriminants (Derived_Type,
6083 Has_Unknown_Discriminants (Parent_Type));
6085 if Is_Private_Type (Derived_Type) then
6086 Set_Private_Dependents (Derived_Type, New_Elmt_List);
6089 if Is_Private_Type (Parent_Type)
6090 and then Base_Type (Parent_Type) = Parent_Type
6091 and then In_Open_Scopes (Scope (Parent_Type))
6093 Append_Elmt (Derived_Type, Private_Dependents (Parent_Type));
6095 if Is_Child_Unit (Scope (Current_Scope))
6096 and then Is_Completion
6097 and then In_Private_Part (Current_Scope)
6098 and then Scope (Parent_Type) /= Current_Scope
6100 -- This is the unusual case where a type completed by a private
6101 -- derivation occurs within a package nested in a child unit, and
6102 -- the parent is declared in an ancestor. In this case, the full
6103 -- view of the parent type will become visible in the body of
6104 -- the enclosing child, and only then will the current type be
6105 -- possibly non-private. We build a underlying full view that
6106 -- will be installed when the enclosing child body is compiled.
6109 Make_Defining_Identifier (Sloc (Derived_Type),
6110 Chars => Chars (Derived_Type));
6111 Set_Is_Itype (Full_Der);
6112 Build_Itype_Reference (Full_Der, N);
6114 -- The full view will be used to swap entities on entry/exit to
6115 -- the body, and must appear in the entity list for the package.
6117 Append_Entity (Full_Der, Scope (Derived_Type));
6118 Set_Has_Private_Declaration (Full_Der);
6119 Set_Has_Private_Declaration (Derived_Type);
6120 Set_Associated_Node_For_Itype (Full_Der, N);
6121 Set_Parent (Full_Der, Parent (Derived_Type));
6122 Full_P := Full_View (Parent_Type);
6123 Exchange_Declarations (Parent_Type);
6125 Exchange_Declarations (Full_P);
6126 Set_Underlying_Full_View (Derived_Type, Full_Der);
6129 end Build_Derived_Private_Type;
6131 -------------------------------
6132 -- Build_Derived_Record_Type --
6133 -------------------------------
6137 -- Ideally we would like to use the same model of type derivation for
6138 -- tagged and untagged record types. Unfortunately this is not quite
6139 -- possible because the semantics of representation clauses is different
6140 -- for tagged and untagged records under inheritance. Consider the
6143 -- type R (...) is [tagged] record ... end record;
6144 -- type T (...) is new R (...) [with ...];
6146 -- The representation clauses for T can specify a completely different
6147 -- record layout from R's. Hence the same component can be placed in two
6148 -- very different positions in objects of type T and R. If R and T are
6149 -- tagged types, representation clauses for T can only specify the layout
6150 -- of non inherited components, thus components that are common in R and T
6151 -- have the same position in objects of type R and T.
6153 -- This has two implications. The first is that the entire tree for R's
6154 -- declaration needs to be copied for T in the untagged case, so that T
6155 -- can be viewed as a record type of its own with its own representation
6156 -- clauses. The second implication is the way we handle discriminants.
6157 -- Specifically, in the untagged case we need a way to communicate to Gigi
6158 -- what are the real discriminants in the record, while for the semantics
6159 -- we need to consider those introduced by the user to rename the
6160 -- discriminants in the parent type. This is handled by introducing the
6161 -- notion of stored discriminants. See below for more.
6163 -- Fortunately the way regular components are inherited can be handled in
6164 -- the same way in tagged and untagged types.
6166 -- To complicate things a bit more the private view of a private extension
6167 -- cannot be handled in the same way as the full view (for one thing the
6168 -- semantic rules are somewhat different). We will explain what differs
6171 -- 2. DISCRIMINANTS UNDER INHERITANCE
6173 -- The semantic rules governing the discriminants of derived types are
6176 -- type Derived_Type_Name [KNOWN_DISCRIMINANT_PART] is new
6177 -- [abstract] Parent_Type_Name [CONSTRAINT] [RECORD_EXTENSION_PART]
6179 -- If parent type has discriminants, then the discriminants that are
6180 -- declared in the derived type are [3.4 (11)]:
6182 -- o The discriminants specified by a new KNOWN_DISCRIMINANT_PART, if
6185 -- o Otherwise, each discriminant of the parent type (implicitly declared
6186 -- in the same order with the same specifications). In this case, the
6187 -- discriminants are said to be "inherited", or if unknown in the parent
6188 -- are also unknown in the derived type.
6190 -- Furthermore if a KNOWN_DISCRIMINANT_PART is provided, then [3.7(13-18)]:
6192 -- o The parent subtype shall be constrained;
6194 -- o If the parent type is not a tagged type, then each discriminant of
6195 -- the derived type shall be used in the constraint defining a parent
6196 -- subtype. [Implementation note: This ensures that the new discriminant
6197 -- can share storage with an existing discriminant.]
6199 -- For the derived type each discriminant of the parent type is either
6200 -- inherited, constrained to equal some new discriminant of the derived
6201 -- type, or constrained to the value of an expression.
6203 -- When inherited or constrained to equal some new discriminant, the
6204 -- parent discriminant and the discriminant of the derived type are said
6207 -- If a discriminant of the parent type is constrained to a specific value
6208 -- in the derived type definition, then the discriminant is said to be
6209 -- "specified" by that derived type definition.
6211 -- 3. DISCRIMINANTS IN DERIVED UNTAGGED RECORD TYPES
6213 -- We have spoken about stored discriminants in point 1 (introduction)
6214 -- above. There are two sort of stored discriminants: implicit and
6215 -- explicit. As long as the derived type inherits the same discriminants as
6216 -- the root record type, stored discriminants are the same as regular
6217 -- discriminants, and are said to be implicit. However, if any discriminant
6218 -- in the root type was renamed in the derived type, then the derived
6219 -- type will contain explicit stored discriminants. Explicit stored
6220 -- discriminants are discriminants in addition to the semantically visible
6221 -- discriminants defined for the derived type. Stored discriminants are
6222 -- used by Gigi to figure out what are the physical discriminants in
6223 -- objects of the derived type (see precise definition in einfo.ads).
6224 -- As an example, consider the following:
6226 -- type R (D1, D2, D3 : Int) is record ... end record;
6227 -- type T1 is new R;
6228 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1);
6229 -- type T3 is new T2;
6230 -- type T4 (Y : Int) is new T3 (Y, 99);
6232 -- The following table summarizes the discriminants and stored
6233 -- discriminants in R and T1 through T4.
6235 -- Type Discrim Stored Discrim Comment
6236 -- R (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in R
6237 -- T1 (D1, D2, D3) (D1, D2, D3) Girder discrims implicit in T1
6238 -- T2 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T2
6239 -- T3 (X1, X2) (D1, D2, D3) Girder discrims EXPLICIT in T3
6240 -- T4 (Y) (D1, D2, D3) Girder discrims EXPLICIT in T4
6242 -- Field Corresponding_Discriminant (abbreviated CD below) allows us to
6243 -- find the corresponding discriminant in the parent type, while
6244 -- Original_Record_Component (abbreviated ORC below), the actual physical
6245 -- component that is renamed. Finally the field Is_Completely_Hidden
6246 -- (abbreviated ICH below) is set for all explicit stored discriminants
6247 -- (see einfo.ads for more info). For the above example this gives:
6249 -- Discrim CD ORC ICH
6250 -- ^^^^^^^ ^^ ^^^ ^^^
6251 -- D1 in R empty itself no
6252 -- D2 in R empty itself no
6253 -- D3 in R empty itself no
6255 -- D1 in T1 D1 in R itself no
6256 -- D2 in T1 D2 in R itself no
6257 -- D3 in T1 D3 in R itself no
6259 -- X1 in T2 D3 in T1 D3 in T2 no
6260 -- X2 in T2 D1 in T1 D1 in T2 no
6261 -- D1 in T2 empty itself yes
6262 -- D2 in T2 empty itself yes
6263 -- D3 in T2 empty itself yes
6265 -- X1 in T3 X1 in T2 D3 in T3 no
6266 -- X2 in T3 X2 in T2 D1 in T3 no
6267 -- D1 in T3 empty itself yes
6268 -- D2 in T3 empty itself yes
6269 -- D3 in T3 empty itself yes
6271 -- Y in T4 X1 in T3 D3 in T3 no
6272 -- D1 in T3 empty itself yes
6273 -- D2 in T3 empty itself yes
6274 -- D3 in T3 empty itself yes
6276 -- 4. DISCRIMINANTS IN DERIVED TAGGED RECORD TYPES
6278 -- Type derivation for tagged types is fairly straightforward. If no
6279 -- discriminants are specified by the derived type, these are inherited
6280 -- from the parent. No explicit stored discriminants are ever necessary.
6281 -- The only manipulation that is done to the tree is that of adding a
6282 -- _parent field with parent type and constrained to the same constraint
6283 -- specified for the parent in the derived type definition. For instance:
6285 -- type R (D1, D2, D3 : Int) is tagged record ... end record;
6286 -- type T1 is new R with null record;
6287 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with null record;
6289 -- are changed into:
6291 -- type T1 (D1, D2, D3 : Int) is new R (D1, D2, D3) with record
6292 -- _parent : R (D1, D2, D3);
6295 -- type T2 (X1, X2: Int) is new T1 (X2, 88, X1) with record
6296 -- _parent : T1 (X2, 88, X1);
6299 -- The discriminants actually present in R, T1 and T2 as well as their CD,
6300 -- ORC and ICH fields are:
6302 -- Discrim CD ORC ICH
6303 -- ^^^^^^^ ^^ ^^^ ^^^
6304 -- D1 in R empty itself no
6305 -- D2 in R empty itself no
6306 -- D3 in R empty itself no
6308 -- D1 in T1 D1 in R D1 in R no
6309 -- D2 in T1 D2 in R D2 in R no
6310 -- D3 in T1 D3 in R D3 in R no
6312 -- X1 in T2 D3 in T1 D3 in R no
6313 -- X2 in T2 D1 in T1 D1 in R no
6315 -- 5. FIRST TRANSFORMATION FOR DERIVED RECORDS
6317 -- Regardless of whether we dealing with a tagged or untagged type
6318 -- we will transform all derived type declarations of the form
6320 -- type T is new R (...) [with ...];
6322 -- subtype S is R (...);
6323 -- type T is new S [with ...];
6325 -- type BT is new R [with ...];
6326 -- subtype T is BT (...);
6328 -- That is, the base derived type is constrained only if it has no
6329 -- discriminants. The reason for doing this is that GNAT's semantic model
6330 -- assumes that a base type with discriminants is unconstrained.
6332 -- Note that, strictly speaking, the above transformation is not always
6333 -- correct. Consider for instance the following excerpt from ACVC b34011a:
6335 -- procedure B34011A is
6336 -- type REC (D : integer := 0) is record
6341 -- type T6 is new Rec;
6342 -- function F return T6;
6347 -- type U is new T6 (Q6.F.I); -- ERROR: Q6.F.
6350 -- The definition of Q6.U is illegal. However transforming Q6.U into
6352 -- type BaseU is new T6;
6353 -- subtype U is BaseU (Q6.F.I)
6355 -- turns U into a legal subtype, which is incorrect. To avoid this problem
6356 -- we always analyze the constraint (in this case (Q6.F.I)) before applying
6357 -- the transformation described above.
6359 -- There is another instance where the above transformation is incorrect.
6363 -- type Base (D : Integer) is tagged null record;
6364 -- procedure P (X : Base);
6366 -- type Der is new Base (2) with null record;
6367 -- procedure P (X : Der);
6370 -- Then the above transformation turns this into
6372 -- type Der_Base is new Base with null record;
6373 -- -- procedure P (X : Base) is implicitly inherited here
6374 -- -- as procedure P (X : Der_Base).
6376 -- subtype Der is Der_Base (2);
6377 -- procedure P (X : Der);
6378 -- -- The overriding of P (X : Der_Base) is illegal since we
6379 -- -- have a parameter conformance problem.
6381 -- To get around this problem, after having semantically processed Der_Base
6382 -- and the rewritten subtype declaration for Der, we copy Der_Base field
6383 -- Discriminant_Constraint from Der so that when parameter conformance is
6384 -- checked when P is overridden, no semantic errors are flagged.
6386 -- 6. SECOND TRANSFORMATION FOR DERIVED RECORDS
6388 -- Regardless of whether we are dealing with a tagged or untagged type
6389 -- we will transform all derived type declarations of the form
6391 -- type R (D1, .., Dn : ...) is [tagged] record ...;
6392 -- type T is new R [with ...];
6394 -- type T (D1, .., Dn : ...) is new R (D1, .., Dn) [with ...];
6396 -- The reason for such transformation is that it allows us to implement a
6397 -- very clean form of component inheritance as explained below.
6399 -- Note that this transformation is not achieved by direct tree rewriting
6400 -- and manipulation, but rather by redoing the semantic actions that the
6401 -- above transformation will entail. This is done directly in routine
6402 -- Inherit_Components.
6404 -- 7. TYPE DERIVATION AND COMPONENT INHERITANCE
6406 -- In both tagged and untagged derived types, regular non discriminant
6407 -- components are inherited in the derived type from the parent type. In
6408 -- the absence of discriminants component, inheritance is straightforward
6409 -- as components can simply be copied from the parent.
6411 -- If the parent has discriminants, inheriting components constrained with
6412 -- these discriminants requires caution. Consider the following example:
6414 -- type R (D1, D2 : Positive) is [tagged] record
6415 -- S : String (D1 .. D2);
6418 -- type T1 is new R [with null record];
6419 -- type T2 (X : positive) is new R (1, X) [with null record];
6421 -- As explained in 6. above, T1 is rewritten as
6422 -- type T1 (D1, D2 : Positive) is new R (D1, D2) [with null record];
6423 -- which makes the treatment for T1 and T2 identical.
6425 -- What we want when inheriting S, is that references to D1 and D2 in R are
6426 -- replaced with references to their correct constraints, i.e. D1 and D2 in
6427 -- T1 and 1 and X in T2. So all R's discriminant references are replaced
6428 -- with either discriminant references in the derived type or expressions.
6429 -- This replacement is achieved as follows: before inheriting R's
6430 -- components, a subtype R (D1, D2) for T1 (resp. R (1, X) for T2) is
6431 -- created in the scope of T1 (resp. scope of T2) so that discriminants D1
6432 -- and D2 of T1 are visible (resp. discriminant X of T2 is visible).
6433 -- For T2, for instance, this has the effect of replacing String (D1 .. D2)
6434 -- by String (1 .. X).
6436 -- 8. TYPE DERIVATION IN PRIVATE TYPE EXTENSIONS
6438 -- We explain here the rules governing private type extensions relevant to
6439 -- type derivation. These rules are explained on the following example:
6441 -- type D [(...)] is new A [(...)] with private; <-- partial view
6442 -- type D [(...)] is new P [(...)] with null record; <-- full view
6444 -- Type A is called the ancestor subtype of the private extension.
6445 -- Type P is the parent type of the full view of the private extension. It
6446 -- must be A or a type derived from A.
6448 -- The rules concerning the discriminants of private type extensions are
6451 -- o If a private extension inherits known discriminants from the ancestor
6452 -- subtype, then the full view shall also inherit its discriminants from
6453 -- the ancestor subtype and the parent subtype of the full view shall be
6454 -- constrained if and only if the ancestor subtype is constrained.
6456 -- o If a partial view has unknown discriminants, then the full view may
6457 -- define a definite or an indefinite subtype, with or without
6460 -- o If a partial view has neither known nor unknown discriminants, then
6461 -- the full view shall define a definite subtype.
6463 -- o If the ancestor subtype of a private extension has constrained
6464 -- discriminants, then the parent subtype of the full view shall impose a
6465 -- statically matching constraint on those discriminants.
6467 -- This means that only the following forms of private extensions are
6470 -- type D is new A with private; <-- partial view
6471 -- type D is new P with null record; <-- full view
6473 -- If A has no discriminants than P has no discriminants, otherwise P must
6474 -- inherit A's discriminants.
6476 -- type D is new A (...) with private; <-- partial view
6477 -- type D is new P (:::) with null record; <-- full view
6479 -- P must inherit A's discriminants and (...) and (:::) must statically
6482 -- subtype A is R (...);
6483 -- type D is new A with private; <-- partial view
6484 -- type D is new P with null record; <-- full view
6486 -- P must have inherited R's discriminants and must be derived from A or
6487 -- any of its subtypes.
6489 -- type D (..) is new A with private; <-- partial view
6490 -- type D (..) is new P [(:::)] with null record; <-- full view
6492 -- No specific constraints on P's discriminants or constraint (:::).
6493 -- Note that A can be unconstrained, but the parent subtype P must either
6494 -- be constrained or (:::) must be present.
6496 -- type D (..) is new A [(...)] with private; <-- partial view
6497 -- type D (..) is new P [(:::)] with null record; <-- full view
6499 -- P's constraints on A's discriminants must statically match those
6500 -- imposed by (...).
6502 -- 9. IMPLEMENTATION OF TYPE DERIVATION FOR PRIVATE EXTENSIONS
6504 -- The full view of a private extension is handled exactly as described
6505 -- above. The model chose for the private view of a private extension is
6506 -- the same for what concerns discriminants (i.e. they receive the same
6507 -- treatment as in the tagged case). However, the private view of the
6508 -- private extension always inherits the components of the parent base,
6509 -- without replacing any discriminant reference. Strictly speaking this is
6510 -- incorrect. However, Gigi never uses this view to generate code so this
6511 -- is a purely semantic issue. In theory, a set of transformations similar
6512 -- to those given in 5. and 6. above could be applied to private views of
6513 -- private extensions to have the same model of component inheritance as
6514 -- for non private extensions. However, this is not done because it would
6515 -- further complicate private type processing. Semantically speaking, this
6516 -- leaves us in an uncomfortable situation. As an example consider:
6519 -- type R (D : integer) is tagged record
6520 -- S : String (1 .. D);
6522 -- procedure P (X : R);
6523 -- type T is new R (1) with private;
6525 -- type T is new R (1) with null record;
6528 -- This is transformed into:
6531 -- type R (D : integer) is tagged record
6532 -- S : String (1 .. D);
6534 -- procedure P (X : R);
6535 -- type T is new R (1) with private;
6537 -- type BaseT is new R with null record;
6538 -- subtype T is BaseT (1);
6541 -- (strictly speaking the above is incorrect Ada)
6543 -- From the semantic standpoint the private view of private extension T
6544 -- should be flagged as constrained since one can clearly have
6548 -- in a unit withing Pack. However, when deriving subprograms for the
6549 -- private view of private extension T, T must be seen as unconstrained
6550 -- since T has discriminants (this is a constraint of the current
6551 -- subprogram derivation model). Thus, when processing the private view of
6552 -- a private extension such as T, we first mark T as unconstrained, we
6553 -- process it, we perform program derivation and just before returning from
6554 -- Build_Derived_Record_Type we mark T as constrained.
6556 -- ??? Are there are other uncomfortable cases that we will have to
6559 -- 10. RECORD_TYPE_WITH_PRIVATE complications
6561 -- Types that are derived from a visible record type and have a private
6562 -- extension present other peculiarities. They behave mostly like private
6563 -- types, but if they have primitive operations defined, these will not
6564 -- have the proper signatures for further inheritance, because other
6565 -- primitive operations will use the implicit base that we define for
6566 -- private derivations below. This affect subprogram inheritance (see
6567 -- Derive_Subprograms for details). We also derive the implicit base from
6568 -- the base type of the full view, so that the implicit base is a record
6569 -- type and not another private type, This avoids infinite loops.
6571 procedure Build_Derived_Record_Type
6573 Parent_Type : Entity_Id;
6574 Derived_Type : Entity_Id;
6575 Derive_Subps : Boolean := True)
6577 Loc : constant Source_Ptr := Sloc (N);
6578 Parent_Base : Entity_Id;
6581 Discrim : Entity_Id;
6582 Last_Discrim : Entity_Id;
6585 Discs : Elist_Id := New_Elmt_List;
6586 -- An empty Discs list means that there were no constraints in the
6587 -- subtype indication or that there was an error processing it.
6589 Assoc_List : Elist_Id;
6590 New_Discrs : Elist_Id;
6591 New_Base : Entity_Id;
6593 New_Indic : Node_Id;
6595 Is_Tagged : constant Boolean := Is_Tagged_Type (Parent_Type);
6596 Discriminant_Specs : constant Boolean :=
6597 Present (Discriminant_Specifications (N));
6598 Private_Extension : constant Boolean :=
6599 Nkind (N) = N_Private_Extension_Declaration;
6601 Constraint_Present : Boolean;
6602 Inherit_Discrims : Boolean := False;
6603 Save_Etype : Entity_Id;
6604 Save_Discr_Constr : Elist_Id;
6605 Save_Next_Entity : Entity_Id;
6608 if Ekind (Parent_Type) = E_Record_Type_With_Private
6609 and then Present (Full_View (Parent_Type))
6610 and then Has_Discriminants (Parent_Type)
6612 Parent_Base := Base_Type (Full_View (Parent_Type));
6614 Parent_Base := Base_Type (Parent_Type);
6617 -- Before we start the previously documented transformations, here is
6618 -- little fix for size and alignment of tagged types. Normally when we
6619 -- derive type D from type P, we copy the size and alignment of P as the
6620 -- default for D, and in the absence of explicit representation clauses
6621 -- for D, the size and alignment are indeed the same as the parent.
6623 -- But this is wrong for tagged types, since fields may be added, and
6624 -- the default size may need to be larger, and the default alignment may
6625 -- need to be larger.
6627 -- We therefore reset the size and alignment fields in the tagged case.
6628 -- Note that the size and alignment will in any case be at least as
6629 -- large as the parent type (since the derived type has a copy of the
6630 -- parent type in the _parent field)
6632 -- The type is also marked as being tagged here, which is needed when
6633 -- processing components with a self-referential anonymous access type
6634 -- in the call to Check_Anonymous_Access_Components below. Note that
6635 -- this flag is also set later on for completeness.
6638 Set_Is_Tagged_Type (Derived_Type);
6639 Init_Size_Align (Derived_Type);
6642 -- STEP 0a: figure out what kind of derived type declaration we have
6644 if Private_Extension then
6646 Set_Ekind (Derived_Type, E_Record_Type_With_Private);
6649 Type_Def := Type_Definition (N);
6651 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
6652 -- Parent_Base can be a private type or private extension. However,
6653 -- for tagged types with an extension the newly added fields are
6654 -- visible and hence the Derived_Type is always an E_Record_Type.
6655 -- (except that the parent may have its own private fields).
6656 -- For untagged types we preserve the Ekind of the Parent_Base.
6658 if Present (Record_Extension_Part (Type_Def)) then
6659 Set_Ekind (Derived_Type, E_Record_Type);
6661 -- Create internal access types for components with anonymous
6664 if Ada_Version >= Ada_05 then
6665 Check_Anonymous_Access_Components
6666 (N, Derived_Type, Derived_Type,
6667 Component_List (Record_Extension_Part (Type_Def)));
6671 Set_Ekind (Derived_Type, Ekind (Parent_Base));
6675 -- Indic can either be an N_Identifier if the subtype indication
6676 -- contains no constraint or an N_Subtype_Indication if the subtype
6677 -- indication has a constraint.
6679 Indic := Subtype_Indication (Type_Def);
6680 Constraint_Present := (Nkind (Indic) = N_Subtype_Indication);
6682 -- Check that the type has visible discriminants. The type may be
6683 -- a private type with unknown discriminants whose full view has
6684 -- discriminants which are invisible.
6686 if Constraint_Present then
6687 if not Has_Discriminants (Parent_Base)
6689 (Has_Unknown_Discriminants (Parent_Base)
6690 and then Is_Private_Type (Parent_Base))
6693 ("invalid constraint: type has no discriminant",
6694 Constraint (Indic));
6696 Constraint_Present := False;
6697 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
6699 elsif Is_Constrained (Parent_Type) then
6701 ("invalid constraint: parent type is already constrained",
6702 Constraint (Indic));
6704 Constraint_Present := False;
6705 Rewrite (Indic, New_Copy_Tree (Subtype_Mark (Indic)));
6709 -- STEP 0b: If needed, apply transformation given in point 5. above
6711 if not Private_Extension
6712 and then Has_Discriminants (Parent_Type)
6713 and then not Discriminant_Specs
6714 and then (Is_Constrained (Parent_Type) or else Constraint_Present)
6716 -- First, we must analyze the constraint (see comment in point 5.)
6718 if Constraint_Present then
6719 New_Discrs := Build_Discriminant_Constraints (Parent_Type, Indic);
6721 if Has_Discriminants (Derived_Type)
6722 and then Has_Private_Declaration (Derived_Type)
6723 and then Present (Discriminant_Constraint (Derived_Type))
6725 -- Verify that constraints of the full view statically match
6726 -- those given in the partial view.
6732 C1 := First_Elmt (New_Discrs);
6733 C2 := First_Elmt (Discriminant_Constraint (Derived_Type));
6734 while Present (C1) and then Present (C2) loop
6735 if Fully_Conformant_Expressions (Node (C1), Node (C2))
6737 (Is_OK_Static_Expression (Node (C1))
6739 Is_OK_Static_Expression (Node (C2))
6741 Expr_Value (Node (C1)) = Expr_Value (Node (C2)))
6747 "constraint not conformant to previous declaration",
6758 -- Insert and analyze the declaration for the unconstrained base type
6760 New_Base := Create_Itype (Ekind (Derived_Type), N, Derived_Type, 'B');
6763 Make_Full_Type_Declaration (Loc,
6764 Defining_Identifier => New_Base,
6766 Make_Derived_Type_Definition (Loc,
6767 Abstract_Present => Abstract_Present (Type_Def),
6768 Limited_Present => Limited_Present (Type_Def),
6769 Subtype_Indication =>
6770 New_Occurrence_Of (Parent_Base, Loc),
6771 Record_Extension_Part =>
6772 Relocate_Node (Record_Extension_Part (Type_Def)),
6773 Interface_List => Interface_List (Type_Def)));
6775 Set_Parent (New_Decl, Parent (N));
6776 Mark_Rewrite_Insertion (New_Decl);
6777 Insert_Before (N, New_Decl);
6779 -- Note that this call passes False for the Derive_Subps parameter
6780 -- because subprogram derivation is deferred until after creating
6781 -- the subtype (see below).
6784 (New_Decl, Parent_Base, New_Base,
6785 Is_Completion => True, Derive_Subps => False);
6787 -- ??? This needs re-examination to determine whether the
6788 -- above call can simply be replaced by a call to Analyze.
6790 Set_Analyzed (New_Decl);
6792 -- Insert and analyze the declaration for the constrained subtype
6794 if Constraint_Present then
6796 Make_Subtype_Indication (Loc,
6797 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
6798 Constraint => Relocate_Node (Constraint (Indic)));
6802 Constr_List : constant List_Id := New_List;
6807 C := First_Elmt (Discriminant_Constraint (Parent_Type));
6808 while Present (C) loop
6811 -- It is safe here to call New_Copy_Tree since
6812 -- Force_Evaluation was called on each constraint in
6813 -- Build_Discriminant_Constraints.
6815 Append (New_Copy_Tree (Expr), To => Constr_List);
6821 Make_Subtype_Indication (Loc,
6822 Subtype_Mark => New_Occurrence_Of (New_Base, Loc),
6824 Make_Index_Or_Discriminant_Constraint (Loc, Constr_List));
6829 Make_Subtype_Declaration (Loc,
6830 Defining_Identifier => Derived_Type,
6831 Subtype_Indication => New_Indic));
6835 -- Derivation of subprograms must be delayed until the full subtype
6836 -- has been established to ensure proper overriding of subprograms
6837 -- inherited by full types. If the derivations occurred as part of
6838 -- the call to Build_Derived_Type above, then the check for type
6839 -- conformance would fail because earlier primitive subprograms
6840 -- could still refer to the full type prior the change to the new
6841 -- subtype and hence would not match the new base type created here.
6843 Derive_Subprograms (Parent_Type, Derived_Type);
6845 -- For tagged types the Discriminant_Constraint of the new base itype
6846 -- is inherited from the first subtype so that no subtype conformance
6847 -- problem arise when the first subtype overrides primitive
6848 -- operations inherited by the implicit base type.
6851 Set_Discriminant_Constraint
6852 (New_Base, Discriminant_Constraint (Derived_Type));
6858 -- If we get here Derived_Type will have no discriminants or it will be
6859 -- a discriminated unconstrained base type.
6861 -- STEP 1a: perform preliminary actions/checks for derived tagged types
6865 -- The parent type is frozen for non-private extensions (RM 13.14(7))
6866 -- The declaration of a specific descendant of an interface type
6867 -- freezes the interface type (RM 13.14).
6869 if not Private_Extension
6870 or else Is_Interface (Parent_Base)
6872 Freeze_Before (N, Parent_Type);
6875 -- In Ada 2005 (AI-344), the restriction that a derived tagged type
6876 -- cannot be declared at a deeper level than its parent type is
6877 -- removed. The check on derivation within a generic body is also
6878 -- relaxed, but there's a restriction that a derived tagged type
6879 -- cannot be declared in a generic body if it's derived directly
6880 -- or indirectly from a formal type of that generic.
6882 if Ada_Version >= Ada_05 then
6883 if Present (Enclosing_Generic_Body (Derived_Type)) then
6885 Ancestor_Type : Entity_Id;
6888 -- Check to see if any ancestor of the derived type is a
6891 Ancestor_Type := Parent_Type;
6892 while not Is_Generic_Type (Ancestor_Type)
6893 and then Etype (Ancestor_Type) /= Ancestor_Type
6895 Ancestor_Type := Etype (Ancestor_Type);
6898 -- If the derived type does have a formal type as an
6899 -- ancestor, then it's an error if the derived type is
6900 -- declared within the body of the generic unit that
6901 -- declares the formal type in its generic formal part. It's
6902 -- sufficient to check whether the ancestor type is declared
6903 -- inside the same generic body as the derived type (such as
6904 -- within a nested generic spec), in which case the
6905 -- derivation is legal. If the formal type is declared
6906 -- outside of that generic body, then it's guaranteed that
6907 -- the derived type is declared within the generic body of
6908 -- the generic unit declaring the formal type.
6910 if Is_Generic_Type (Ancestor_Type)
6911 and then Enclosing_Generic_Body (Ancestor_Type) /=
6912 Enclosing_Generic_Body (Derived_Type)
6915 ("parent type of& must not be descendant of formal type"
6916 & " of an enclosing generic body",
6917 Indic, Derived_Type);
6922 elsif Type_Access_Level (Derived_Type) /=
6923 Type_Access_Level (Parent_Type)
6924 and then not Is_Generic_Type (Derived_Type)
6926 if Is_Controlled (Parent_Type) then
6928 ("controlled type must be declared at the library level",
6932 ("type extension at deeper accessibility level than parent",
6938 GB : constant Node_Id := Enclosing_Generic_Body (Derived_Type);
6942 and then GB /= Enclosing_Generic_Body (Parent_Base)
6945 ("parent type of& must not be outside generic body"
6947 Indic, Derived_Type);
6953 -- Ada 2005 (AI-251)
6955 if Ada_Version = Ada_05
6958 -- "The declaration of a specific descendant of an interface type
6959 -- freezes the interface type" (RM 13.14).
6964 if Is_Non_Empty_List (Interface_List (Type_Def)) then
6965 Iface := First (Interface_List (Type_Def));
6966 while Present (Iface) loop
6967 Freeze_Before (N, Etype (Iface));
6974 -- STEP 1b : preliminary cleanup of the full view of private types
6976 -- If the type is already marked as having discriminants, then it's the
6977 -- completion of a private type or private extension and we need to
6978 -- retain the discriminants from the partial view if the current
6979 -- declaration has Discriminant_Specifications so that we can verify
6980 -- conformance. However, we must remove any existing components that
6981 -- were inherited from the parent (and attached in Copy_And_Swap)
6982 -- because the full type inherits all appropriate components anyway, and
6983 -- we do not want the partial view's components interfering.
6985 if Has_Discriminants (Derived_Type) and then Discriminant_Specs then
6986 Discrim := First_Discriminant (Derived_Type);
6988 Last_Discrim := Discrim;
6989 Next_Discriminant (Discrim);
6990 exit when No (Discrim);
6993 Set_Last_Entity (Derived_Type, Last_Discrim);
6995 -- In all other cases wipe out the list of inherited components (even
6996 -- inherited discriminants), it will be properly rebuilt here.
6999 Set_First_Entity (Derived_Type, Empty);
7000 Set_Last_Entity (Derived_Type, Empty);
7003 -- STEP 1c: Initialize some flags for the Derived_Type
7005 -- The following flags must be initialized here so that
7006 -- Process_Discriminants can check that discriminants of tagged types do
7007 -- not have a default initial value and that access discriminants are
7008 -- only specified for limited records. For completeness, these flags are
7009 -- also initialized along with all the other flags below.
7011 -- AI-419: Limitedness is not inherited from an interface parent, so to
7012 -- be limited in that case the type must be explicitly declared as
7013 -- limited. However, task and protected interfaces are always limited.
7015 if Limited_Present (Type_Def) then
7016 Set_Is_Limited_Record (Derived_Type);
7018 elsif Is_Limited_Record (Parent_Type)
7019 or else (Present (Full_View (Parent_Type))
7020 and then Is_Limited_Record (Full_View (Parent_Type)))
7022 if not Is_Interface (Parent_Type)
7023 or else Is_Synchronized_Interface (Parent_Type)
7024 or else Is_Protected_Interface (Parent_Type)
7025 or else Is_Task_Interface (Parent_Type)
7027 Set_Is_Limited_Record (Derived_Type);
7031 -- STEP 2a: process discriminants of derived type if any
7033 Push_Scope (Derived_Type);
7035 if Discriminant_Specs then
7036 Set_Has_Unknown_Discriminants (Derived_Type, False);
7038 -- The following call initializes fields Has_Discriminants and
7039 -- Discriminant_Constraint, unless we are processing the completion
7040 -- of a private type declaration.
7042 Check_Or_Process_Discriminants (N, Derived_Type);
7044 -- For non-tagged types the constraint on the Parent_Type must be
7045 -- present and is used to rename the discriminants.
7047 if not Is_Tagged and then not Has_Discriminants (Parent_Type) then
7048 Error_Msg_N ("untagged parent must have discriminants", Indic);
7050 elsif not Is_Tagged and then not Constraint_Present then
7052 ("discriminant constraint needed for derived untagged records",
7055 -- Otherwise the parent subtype must be constrained unless we have a
7056 -- private extension.
7058 elsif not Constraint_Present
7059 and then not Private_Extension
7060 and then not Is_Constrained (Parent_Type)
7063 ("unconstrained type not allowed in this context", Indic);
7065 elsif Constraint_Present then
7066 -- The following call sets the field Corresponding_Discriminant
7067 -- for the discriminants in the Derived_Type.
7069 Discs := Build_Discriminant_Constraints (Parent_Type, Indic, True);
7071 -- For untagged types all new discriminants must rename
7072 -- discriminants in the parent. For private extensions new
7073 -- discriminants cannot rename old ones (implied by [7.3(13)]).
7075 Discrim := First_Discriminant (Derived_Type);
7076 while Present (Discrim) loop
7078 and then No (Corresponding_Discriminant (Discrim))
7081 ("new discriminants must constrain old ones", Discrim);
7083 elsif Private_Extension
7084 and then Present (Corresponding_Discriminant (Discrim))
7087 ("only static constraints allowed for parent"
7088 & " discriminants in the partial view", Indic);
7092 -- If a new discriminant is used in the constraint, then its
7093 -- subtype must be statically compatible with the parent
7094 -- discriminant's subtype (3.7(15)).
7096 if Present (Corresponding_Discriminant (Discrim))
7098 not Subtypes_Statically_Compatible
7100 Etype (Corresponding_Discriminant (Discrim)))
7103 ("subtype must be compatible with parent discriminant",
7107 Next_Discriminant (Discrim);
7110 -- Check whether the constraints of the full view statically
7111 -- match those imposed by the parent subtype [7.3(13)].
7113 if Present (Stored_Constraint (Derived_Type)) then
7118 C1 := First_Elmt (Discs);
7119 C2 := First_Elmt (Stored_Constraint (Derived_Type));
7120 while Present (C1) and then Present (C2) loop
7122 Fully_Conformant_Expressions (Node (C1), Node (C2))
7125 ("not conformant with previous declaration",
7136 -- STEP 2b: No new discriminants, inherit discriminants if any
7139 if Private_Extension then
7140 Set_Has_Unknown_Discriminants
7142 Has_Unknown_Discriminants (Parent_Type)
7143 or else Unknown_Discriminants_Present (N));
7145 -- The partial view of the parent may have unknown discriminants,
7146 -- but if the full view has discriminants and the parent type is
7147 -- in scope they must be inherited.
7149 elsif Has_Unknown_Discriminants (Parent_Type)
7151 (not Has_Discriminants (Parent_Type)
7152 or else not In_Open_Scopes (Scope (Parent_Type)))
7154 Set_Has_Unknown_Discriminants (Derived_Type);
7157 if not Has_Unknown_Discriminants (Derived_Type)
7158 and then not Has_Unknown_Discriminants (Parent_Base)
7159 and then Has_Discriminants (Parent_Type)
7161 Inherit_Discrims := True;
7162 Set_Has_Discriminants
7163 (Derived_Type, True);
7164 Set_Discriminant_Constraint
7165 (Derived_Type, Discriminant_Constraint (Parent_Base));
7168 -- The following test is true for private types (remember
7169 -- transformation 5. is not applied to those) and in an error
7172 if Constraint_Present then
7173 Discs := Build_Discriminant_Constraints (Parent_Type, Indic);
7176 -- For now mark a new derived type as constrained only if it has no
7177 -- discriminants. At the end of Build_Derived_Record_Type we properly
7178 -- set this flag in the case of private extensions. See comments in
7179 -- point 9. just before body of Build_Derived_Record_Type.
7183 not (Inherit_Discrims
7184 or else Has_Unknown_Discriminants (Derived_Type)));
7187 -- STEP 3: initialize fields of derived type
7189 Set_Is_Tagged_Type (Derived_Type, Is_Tagged);
7190 Set_Stored_Constraint (Derived_Type, No_Elist);
7192 -- Ada 2005 (AI-251): Private type-declarations can implement interfaces
7193 -- but cannot be interfaces
7195 if not Private_Extension
7196 and then Ekind (Derived_Type) /= E_Private_Type
7197 and then Ekind (Derived_Type) /= E_Limited_Private_Type
7199 if Interface_Present (Type_Def) then
7200 Analyze_Interface_Declaration (Derived_Type, Type_Def);
7203 Set_Interfaces (Derived_Type, No_Elist);
7206 -- Fields inherited from the Parent_Type
7209 (Derived_Type, Einfo.Discard_Names (Parent_Type));
7210 Set_Has_Specified_Layout
7211 (Derived_Type, Has_Specified_Layout (Parent_Type));
7212 Set_Is_Limited_Composite
7213 (Derived_Type, Is_Limited_Composite (Parent_Type));
7214 Set_Is_Private_Composite
7215 (Derived_Type, Is_Private_Composite (Parent_Type));
7217 -- Fields inherited from the Parent_Base
7219 Set_Has_Controlled_Component
7220 (Derived_Type, Has_Controlled_Component (Parent_Base));
7221 Set_Has_Non_Standard_Rep
7222 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7223 Set_Has_Primitive_Operations
7224 (Derived_Type, Has_Primitive_Operations (Parent_Base));
7226 -- Fields inherited from the Parent_Base in the non-private case
7228 if Ekind (Derived_Type) = E_Record_Type then
7229 Set_Has_Complex_Representation
7230 (Derived_Type, Has_Complex_Representation (Parent_Base));
7233 -- Fields inherited from the Parent_Base for record types
7235 if Is_Record_Type (Derived_Type) then
7237 -- Ekind (Parent_Base) is not necessarily E_Record_Type since
7238 -- Parent_Base can be a private type or private extension.
7240 if Present (Full_View (Parent_Base)) then
7241 Set_OK_To_Reorder_Components
7243 OK_To_Reorder_Components (Full_View (Parent_Base)));
7244 Set_Reverse_Bit_Order
7245 (Derived_Type, Reverse_Bit_Order (Full_View (Parent_Base)));
7247 Set_OK_To_Reorder_Components
7248 (Derived_Type, OK_To_Reorder_Components (Parent_Base));
7249 Set_Reverse_Bit_Order
7250 (Derived_Type, Reverse_Bit_Order (Parent_Base));
7254 -- Direct controlled types do not inherit Finalize_Storage_Only flag
7256 if not Is_Controlled (Parent_Type) then
7257 Set_Finalize_Storage_Only
7258 (Derived_Type, Finalize_Storage_Only (Parent_Type));
7261 -- Set fields for private derived types
7263 if Is_Private_Type (Derived_Type) then
7264 Set_Depends_On_Private (Derived_Type, True);
7265 Set_Private_Dependents (Derived_Type, New_Elmt_List);
7267 -- Inherit fields from non private record types. If this is the
7268 -- completion of a derivation from a private type, the parent itself
7269 -- is private, and the attributes come from its full view, which must
7273 if Is_Private_Type (Parent_Base)
7274 and then not Is_Record_Type (Parent_Base)
7276 Set_Component_Alignment
7277 (Derived_Type, Component_Alignment (Full_View (Parent_Base)));
7279 (Derived_Type, C_Pass_By_Copy (Full_View (Parent_Base)));
7281 Set_Component_Alignment
7282 (Derived_Type, Component_Alignment (Parent_Base));
7284 (Derived_Type, C_Pass_By_Copy (Parent_Base));
7288 -- Set fields for tagged types
7291 Set_Primitive_Operations (Derived_Type, New_Elmt_List);
7293 -- All tagged types defined in Ada.Finalization are controlled
7295 if Chars (Scope (Derived_Type)) = Name_Finalization
7296 and then Chars (Scope (Scope (Derived_Type))) = Name_Ada
7297 and then Scope (Scope (Scope (Derived_Type))) = Standard_Standard
7299 Set_Is_Controlled (Derived_Type);
7301 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Base));
7304 -- Minor optimization: there is no need to generate the class-wide
7305 -- entity associated with an underlying record view.
7307 if not Is_Underlying_Record_View (Derived_Type) then
7308 Make_Class_Wide_Type (Derived_Type);
7311 Set_Is_Abstract_Type (Derived_Type, Abstract_Present (Type_Def));
7313 if Has_Discriminants (Derived_Type)
7314 and then Constraint_Present
7316 Set_Stored_Constraint
7317 (Derived_Type, Expand_To_Stored_Constraint (Parent_Base, Discs));
7320 if Ada_Version >= Ada_05 then
7322 Ifaces_List : Elist_Id;
7325 -- Checks rules 3.9.4 (13/2 and 14/2)
7327 if Comes_From_Source (Derived_Type)
7328 and then not Is_Private_Type (Derived_Type)
7329 and then Is_Interface (Parent_Type)
7330 and then not Is_Interface (Derived_Type)
7332 if Is_Task_Interface (Parent_Type) then
7334 ("(Ada 2005) task type required (RM 3.9.4 (13.2))",
7337 elsif Is_Protected_Interface (Parent_Type) then
7339 ("(Ada 2005) protected type required (RM 3.9.4 (14.2))",
7344 -- Check ARM rules 3.9.4 (15/2), 9.1 (9.d/2) and 9.4 (11.d/2)
7346 Check_Interfaces (N, Type_Def);
7348 -- Ada 2005 (AI-251): Collect the list of progenitors that are
7349 -- not already in the parents.
7353 Ifaces_List => Ifaces_List,
7354 Exclude_Parents => True);
7356 Set_Interfaces (Derived_Type, Ifaces_List);
7361 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
7362 Set_Has_Non_Standard_Rep
7363 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7366 -- STEP 4: Inherit components from the parent base and constrain them.
7367 -- Apply the second transformation described in point 6. above.
7369 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
7370 or else not Has_Discriminants (Parent_Type)
7371 or else not Is_Constrained (Parent_Type)
7375 Constrs := Discriminant_Constraint (Parent_Type);
7380 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
7382 -- STEP 5a: Copy the parent record declaration for untagged types
7384 if not Is_Tagged then
7386 -- Discriminant_Constraint (Derived_Type) has been properly
7387 -- constructed. Save it and temporarily set it to Empty because we
7388 -- do not want the call to New_Copy_Tree below to mess this list.
7390 if Has_Discriminants (Derived_Type) then
7391 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
7392 Set_Discriminant_Constraint (Derived_Type, No_Elist);
7394 Save_Discr_Constr := No_Elist;
7397 -- Save the Etype field of Derived_Type. It is correctly set now,
7398 -- but the call to New_Copy tree may remap it to point to itself,
7399 -- which is not what we want. Ditto for the Next_Entity field.
7401 Save_Etype := Etype (Derived_Type);
7402 Save_Next_Entity := Next_Entity (Derived_Type);
7404 -- Assoc_List maps all stored discriminants in the Parent_Base to
7405 -- stored discriminants in the Derived_Type. It is fundamental that
7406 -- no types or itypes with discriminants other than the stored
7407 -- discriminants appear in the entities declared inside
7408 -- Derived_Type, since the back end cannot deal with it.
7412 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
7414 -- Restore the fields saved prior to the New_Copy_Tree call
7415 -- and compute the stored constraint.
7417 Set_Etype (Derived_Type, Save_Etype);
7418 Set_Next_Entity (Derived_Type, Save_Next_Entity);
7420 if Has_Discriminants (Derived_Type) then
7421 Set_Discriminant_Constraint
7422 (Derived_Type, Save_Discr_Constr);
7423 Set_Stored_Constraint
7424 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
7425 Replace_Components (Derived_Type, New_Decl);
7428 -- Insert the new derived type declaration
7430 Rewrite (N, New_Decl);
7432 -- STEP 5b: Complete the processing for record extensions in generics
7434 -- There is no completion for record extensions declared in the
7435 -- parameter part of a generic, so we need to complete processing for
7436 -- these generic record extensions here. The Record_Type_Definition call
7437 -- will change the Ekind of the components from E_Void to E_Component.
7439 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
7440 Record_Type_Definition (Empty, Derived_Type);
7442 -- STEP 5c: Process the record extension for non private tagged types
7444 elsif not Private_Extension then
7446 -- Add the _parent field in the derived type
7448 Expand_Record_Extension (Derived_Type, Type_Def);
7450 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
7451 -- implemented interfaces if we are in expansion mode
7454 and then Has_Interfaces (Derived_Type)
7456 Add_Interface_Tag_Components (N, Derived_Type);
7459 -- Analyze the record extension
7461 Record_Type_Definition
7462 (Record_Extension_Part (Type_Def), Derived_Type);
7467 -- Nothing else to do if there is an error in the derivation.
7468 -- An unusual case: the full view may be derived from a type in an
7469 -- instance, when the partial view was used illegally as an actual
7470 -- in that instance, leading to a circular definition.
7472 if Etype (Derived_Type) = Any_Type
7473 or else Etype (Parent_Type) = Derived_Type
7478 -- Set delayed freeze and then derive subprograms, we need to do
7479 -- this in this order so that derived subprograms inherit the
7480 -- derived freeze if necessary.
7482 Set_Has_Delayed_Freeze (Derived_Type);
7484 if Derive_Subps then
7485 Derive_Subprograms (Parent_Type, Derived_Type);
7488 -- If we have a private extension which defines a constrained derived
7489 -- type mark as constrained here after we have derived subprograms. See
7490 -- comment on point 9. just above the body of Build_Derived_Record_Type.
7492 if Private_Extension and then Inherit_Discrims then
7493 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
7494 Set_Is_Constrained (Derived_Type, True);
7495 Set_Discriminant_Constraint (Derived_Type, Discs);
7497 elsif Is_Constrained (Parent_Type) then
7499 (Derived_Type, True);
7500 Set_Discriminant_Constraint
7501 (Derived_Type, Discriminant_Constraint (Parent_Type));
7505 -- Update the class-wide type, which shares the now-completed entity
7506 -- list with its specific type. In case of underlying record views,
7507 -- we do not generate the corresponding class wide entity.
7510 and then not Is_Underlying_Record_View (Derived_Type)
7513 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
7515 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
7518 -- Update the scope of anonymous access types of discriminants and other
7519 -- components, to prevent scope anomalies in gigi, when the derivation
7520 -- appears in a scope nested within that of the parent.
7526 D := First_Entity (Derived_Type);
7527 while Present (D) loop
7528 if Ekind (D) = E_Discriminant
7529 or else Ekind (D) = E_Component
7531 if Is_Itype (Etype (D))
7532 and then Ekind (Etype (D)) = E_Anonymous_Access_Type
7534 Set_Scope (Etype (D), Current_Scope);
7541 end Build_Derived_Record_Type;
7543 ------------------------
7544 -- Build_Derived_Type --
7545 ------------------------
7547 procedure Build_Derived_Type
7549 Parent_Type : Entity_Id;
7550 Derived_Type : Entity_Id;
7551 Is_Completion : Boolean;
7552 Derive_Subps : Boolean := True)
7554 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
7557 -- Set common attributes
7559 Set_Scope (Derived_Type, Current_Scope);
7561 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7562 Set_Etype (Derived_Type, Parent_Base);
7563 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
7565 Set_Size_Info (Derived_Type, Parent_Type);
7566 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
7567 Set_Convention (Derived_Type, Convention (Parent_Type));
7568 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7569 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
7571 -- The derived type inherits the representation clauses of the parent.
7572 -- However, for a private type that is completed by a derivation, there
7573 -- may be operation attributes that have been specified already (stream
7574 -- attributes and External_Tag) and those must be provided. Finally,
7575 -- if the partial view is a private extension, the representation items
7576 -- of the parent have been inherited already, and should not be chained
7577 -- twice to the derived type.
7579 if Is_Tagged_Type (Parent_Type)
7580 and then Present (First_Rep_Item (Derived_Type))
7582 -- The existing items are either operational items or items inherited
7583 -- from a private extension declaration.
7587 -- Used to iterate over representation items of the derived type
7590 -- Last representation item of the (non-empty) representation
7591 -- item list of the derived type.
7593 Found : Boolean := False;
7596 Rep := First_Rep_Item (Derived_Type);
7598 while Present (Rep) loop
7599 if Rep = First_Rep_Item (Parent_Type) then
7604 Rep := Next_Rep_Item (Rep);
7606 if Present (Rep) then
7612 -- Here if we either encountered the parent type's first rep
7613 -- item on the derived type's rep item list (in which case
7614 -- Found is True, and we have nothing else to do), or if we
7615 -- reached the last rep item of the derived type, which is
7616 -- Last_Rep, in which case we further chain the parent type's
7617 -- rep items to those of the derived type.
7620 Set_Next_Rep_Item (Last_Rep, First_Rep_Item (Parent_Type));
7625 Set_First_Rep_Item (Derived_Type, First_Rep_Item (Parent_Type));
7628 case Ekind (Parent_Type) is
7629 when Numeric_Kind =>
7630 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
7633 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
7637 | Class_Wide_Kind =>
7638 Build_Derived_Record_Type
7639 (N, Parent_Type, Derived_Type, Derive_Subps);
7642 when Enumeration_Kind =>
7643 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
7646 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
7648 when Incomplete_Or_Private_Kind =>
7649 Build_Derived_Private_Type
7650 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
7652 -- For discriminated types, the derivation includes deriving
7653 -- primitive operations. For others it is done below.
7655 if Is_Tagged_Type (Parent_Type)
7656 or else Has_Discriminants (Parent_Type)
7657 or else (Present (Full_View (Parent_Type))
7658 and then Has_Discriminants (Full_View (Parent_Type)))
7663 when Concurrent_Kind =>
7664 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
7667 raise Program_Error;
7670 if Etype (Derived_Type) = Any_Type then
7674 -- Set delayed freeze and then derive subprograms, we need to do this
7675 -- in this order so that derived subprograms inherit the derived freeze
7678 Set_Has_Delayed_Freeze (Derived_Type);
7679 if Derive_Subps then
7680 Derive_Subprograms (Parent_Type, Derived_Type);
7683 Set_Has_Primitive_Operations
7684 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
7685 end Build_Derived_Type;
7687 -----------------------
7688 -- Build_Discriminal --
7689 -----------------------
7691 procedure Build_Discriminal (Discrim : Entity_Id) is
7692 D_Minal : Entity_Id;
7693 CR_Disc : Entity_Id;
7696 -- A discriminal has the same name as the discriminant
7699 Make_Defining_Identifier (Sloc (Discrim),
7700 Chars => Chars (Discrim));
7702 Set_Ekind (D_Minal, E_In_Parameter);
7703 Set_Mechanism (D_Minal, Default_Mechanism);
7704 Set_Etype (D_Minal, Etype (Discrim));
7706 Set_Discriminal (Discrim, D_Minal);
7707 Set_Discriminal_Link (D_Minal, Discrim);
7709 -- For task types, build at once the discriminants of the corresponding
7710 -- record, which are needed if discriminants are used in entry defaults
7711 -- and in family bounds.
7713 if Is_Concurrent_Type (Current_Scope)
7714 or else Is_Limited_Type (Current_Scope)
7716 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
7718 Set_Ekind (CR_Disc, E_In_Parameter);
7719 Set_Mechanism (CR_Disc, Default_Mechanism);
7720 Set_Etype (CR_Disc, Etype (Discrim));
7721 Set_Discriminal_Link (CR_Disc, Discrim);
7722 Set_CR_Discriminant (Discrim, CR_Disc);
7724 end Build_Discriminal;
7726 ------------------------------------
7727 -- Build_Discriminant_Constraints --
7728 ------------------------------------
7730 function Build_Discriminant_Constraints
7733 Derived_Def : Boolean := False) return Elist_Id
7735 C : constant Node_Id := Constraint (Def);
7736 Nb_Discr : constant Nat := Number_Discriminants (T);
7738 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
7739 -- Saves the expression corresponding to a given discriminant in T
7741 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
7742 -- Return the Position number within array Discr_Expr of a discriminant
7743 -- D within the discriminant list of the discriminated type T.
7749 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
7753 Disc := First_Discriminant (T);
7754 for J in Discr_Expr'Range loop
7759 Next_Discriminant (Disc);
7762 -- Note: Since this function is called on discriminants that are
7763 -- known to belong to the discriminated type, falling through the
7764 -- loop with no match signals an internal compiler error.
7766 raise Program_Error;
7769 -- Declarations local to Build_Discriminant_Constraints
7773 Elist : constant Elist_Id := New_Elmt_List;
7781 Discrim_Present : Boolean := False;
7783 -- Start of processing for Build_Discriminant_Constraints
7786 -- The following loop will process positional associations only.
7787 -- For a positional association, the (single) discriminant is
7788 -- implicitly specified by position, in textual order (RM 3.7.2).
7790 Discr := First_Discriminant (T);
7791 Constr := First (Constraints (C));
7792 for D in Discr_Expr'Range loop
7793 exit when Nkind (Constr) = N_Discriminant_Association;
7796 Error_Msg_N ("too few discriminants given in constraint", C);
7797 return New_Elmt_List;
7799 elsif Nkind (Constr) = N_Range
7800 or else (Nkind (Constr) = N_Attribute_Reference
7802 Attribute_Name (Constr) = Name_Range)
7805 ("a range is not a valid discriminant constraint", Constr);
7806 Discr_Expr (D) := Error;
7809 Analyze_And_Resolve (Constr, Base_Type (Etype (Discr)));
7810 Discr_Expr (D) := Constr;
7813 Next_Discriminant (Discr);
7817 if No (Discr) and then Present (Constr) then
7818 Error_Msg_N ("too many discriminants given in constraint", Constr);
7819 return New_Elmt_List;
7822 -- Named associations can be given in any order, but if both positional
7823 -- and named associations are used in the same discriminant constraint,
7824 -- then positional associations must occur first, at their normal
7825 -- position. Hence once a named association is used, the rest of the
7826 -- discriminant constraint must use only named associations.
7828 while Present (Constr) loop
7830 -- Positional association forbidden after a named association
7832 if Nkind (Constr) /= N_Discriminant_Association then
7833 Error_Msg_N ("positional association follows named one", Constr);
7834 return New_Elmt_List;
7836 -- Otherwise it is a named association
7839 -- E records the type of the discriminants in the named
7840 -- association. All the discriminants specified in the same name
7841 -- association must have the same type.
7845 -- Search the list of discriminants in T to see if the simple name
7846 -- given in the constraint matches any of them.
7848 Id := First (Selector_Names (Constr));
7849 while Present (Id) loop
7852 -- If Original_Discriminant is present, we are processing a
7853 -- generic instantiation and this is an instance node. We need
7854 -- to find the name of the corresponding discriminant in the
7855 -- actual record type T and not the name of the discriminant in
7856 -- the generic formal. Example:
7859 -- type G (D : int) is private;
7861 -- subtype W is G (D => 1);
7863 -- type Rec (X : int) is record ... end record;
7864 -- package Q is new P (G => Rec);
7866 -- At the point of the instantiation, formal type G is Rec
7867 -- and therefore when reanalyzing "subtype W is G (D => 1);"
7868 -- which really looks like "subtype W is Rec (D => 1);" at
7869 -- the point of instantiation, we want to find the discriminant
7870 -- that corresponds to D in Rec, i.e. X.
7872 if Present (Original_Discriminant (Id)) then
7873 Discr := Find_Corresponding_Discriminant (Id, T);
7877 Discr := First_Discriminant (T);
7878 while Present (Discr) loop
7879 if Chars (Discr) = Chars (Id) then
7884 Next_Discriminant (Discr);
7888 Error_Msg_N ("& does not match any discriminant", Id);
7889 return New_Elmt_List;
7891 -- The following is only useful for the benefit of generic
7892 -- instances but it does not interfere with other
7893 -- processing for the non-generic case so we do it in all
7894 -- cases (for generics this statement is executed when
7895 -- processing the generic definition, see comment at the
7896 -- beginning of this if statement).
7899 Set_Original_Discriminant (Id, Discr);
7903 Position := Pos_Of_Discr (T, Discr);
7905 if Present (Discr_Expr (Position)) then
7906 Error_Msg_N ("duplicate constraint for discriminant&", Id);
7909 -- Each discriminant specified in the same named association
7910 -- must be associated with a separate copy of the
7911 -- corresponding expression.
7913 if Present (Next (Id)) then
7914 Expr := New_Copy_Tree (Expression (Constr));
7915 Set_Parent (Expr, Parent (Expression (Constr)));
7917 Expr := Expression (Constr);
7920 Discr_Expr (Position) := Expr;
7921 Analyze_And_Resolve (Expr, Base_Type (Etype (Discr)));
7924 -- A discriminant association with more than one discriminant
7925 -- name is only allowed if the named discriminants are all of
7926 -- the same type (RM 3.7.1(8)).
7929 E := Base_Type (Etype (Discr));
7931 elsif Base_Type (Etype (Discr)) /= E then
7933 ("all discriminants in an association " &
7934 "must have the same type", Id);
7944 -- A discriminant constraint must provide exactly one value for each
7945 -- discriminant of the type (RM 3.7.1(8)).
7947 for J in Discr_Expr'Range loop
7948 if No (Discr_Expr (J)) then
7949 Error_Msg_N ("too few discriminants given in constraint", C);
7950 return New_Elmt_List;
7954 -- Determine if there are discriminant expressions in the constraint
7956 for J in Discr_Expr'Range loop
7957 if Denotes_Discriminant
7958 (Discr_Expr (J), Check_Concurrent => True)
7960 Discrim_Present := True;
7964 -- Build an element list consisting of the expressions given in the
7965 -- discriminant constraint and apply the appropriate checks. The list
7966 -- is constructed after resolving any named discriminant associations
7967 -- and therefore the expressions appear in the textual order of the
7970 Discr := First_Discriminant (T);
7971 for J in Discr_Expr'Range loop
7972 if Discr_Expr (J) /= Error then
7973 Append_Elmt (Discr_Expr (J), Elist);
7975 -- If any of the discriminant constraints is given by a
7976 -- discriminant and we are in a derived type declaration we
7977 -- have a discriminant renaming. Establish link between new
7978 -- and old discriminant.
7980 if Denotes_Discriminant (Discr_Expr (J)) then
7982 Set_Corresponding_Discriminant
7983 (Entity (Discr_Expr (J)), Discr);
7986 -- Force the evaluation of non-discriminant expressions.
7987 -- If we have found a discriminant in the constraint 3.4(26)
7988 -- and 3.8(18) demand that no range checks are performed are
7989 -- after evaluation. If the constraint is for a component
7990 -- definition that has a per-object constraint, expressions are
7991 -- evaluated but not checked either. In all other cases perform
7995 if Discrim_Present then
7998 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
8000 Has_Per_Object_Constraint
8001 (Defining_Identifier (Parent (Parent (Def))))
8005 elsif Is_Access_Type (Etype (Discr)) then
8006 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
8009 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
8012 Force_Evaluation (Discr_Expr (J));
8015 -- Check that the designated type of an access discriminant's
8016 -- expression is not a class-wide type unless the discriminant's
8017 -- designated type is also class-wide.
8019 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
8020 and then not Is_Class_Wide_Type
8021 (Designated_Type (Etype (Discr)))
8022 and then Etype (Discr_Expr (J)) /= Any_Type
8023 and then Is_Class_Wide_Type
8024 (Designated_Type (Etype (Discr_Expr (J))))
8026 Wrong_Type (Discr_Expr (J), Etype (Discr));
8028 elsif Is_Access_Type (Etype (Discr))
8029 and then not Is_Access_Constant (Etype (Discr))
8030 and then Is_Access_Type (Etype (Discr_Expr (J)))
8031 and then Is_Access_Constant (Etype (Discr_Expr (J)))
8034 ("constraint for discriminant& must be access to variable",
8039 Next_Discriminant (Discr);
8043 end Build_Discriminant_Constraints;
8045 ---------------------------------
8046 -- Build_Discriminated_Subtype --
8047 ---------------------------------
8049 procedure Build_Discriminated_Subtype
8053 Related_Nod : Node_Id;
8054 For_Access : Boolean := False)
8056 Has_Discrs : constant Boolean := Has_Discriminants (T);
8057 Constrained : constant Boolean :=
8059 and then not Is_Empty_Elmt_List (Elist)
8060 and then not Is_Class_Wide_Type (T))
8061 or else Is_Constrained (T);
8064 if Ekind (T) = E_Record_Type then
8066 Set_Ekind (Def_Id, E_Private_Subtype);
8067 Set_Is_For_Access_Subtype (Def_Id, True);
8069 Set_Ekind (Def_Id, E_Record_Subtype);
8072 -- Inherit preelaboration flag from base, for types for which it
8073 -- may have been set: records, private types, protected types.
8075 Set_Known_To_Have_Preelab_Init
8076 (Def_Id, Known_To_Have_Preelab_Init (T));
8078 elsif Ekind (T) = E_Task_Type then
8079 Set_Ekind (Def_Id, E_Task_Subtype);
8081 elsif Ekind (T) = E_Protected_Type then
8082 Set_Ekind (Def_Id, E_Protected_Subtype);
8083 Set_Known_To_Have_Preelab_Init
8084 (Def_Id, Known_To_Have_Preelab_Init (T));
8086 elsif Is_Private_Type (T) then
8087 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
8088 Set_Known_To_Have_Preelab_Init
8089 (Def_Id, Known_To_Have_Preelab_Init (T));
8091 elsif Is_Class_Wide_Type (T) then
8092 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
8095 -- Incomplete type. Attach subtype to list of dependents, to be
8096 -- completed with full view of parent type, unless is it the
8097 -- designated subtype of a record component within an init_proc.
8098 -- This last case arises for a component of an access type whose
8099 -- designated type is incomplete (e.g. a Taft Amendment type).
8100 -- The designated subtype is within an inner scope, and needs no
8101 -- elaboration, because only the access type is needed in the
8102 -- initialization procedure.
8104 Set_Ekind (Def_Id, Ekind (T));
8106 if For_Access and then Within_Init_Proc then
8109 Append_Elmt (Def_Id, Private_Dependents (T));
8113 Set_Etype (Def_Id, T);
8114 Init_Size_Align (Def_Id);
8115 Set_Has_Discriminants (Def_Id, Has_Discrs);
8116 Set_Is_Constrained (Def_Id, Constrained);
8118 Set_First_Entity (Def_Id, First_Entity (T));
8119 Set_Last_Entity (Def_Id, Last_Entity (T));
8121 -- If the subtype is the completion of a private declaration, there may
8122 -- have been representation clauses for the partial view, and they must
8123 -- be preserved. Build_Derived_Type chains the inherited clauses with
8124 -- the ones appearing on the extension. If this comes from a subtype
8125 -- declaration, all clauses are inherited.
8127 if No (First_Rep_Item (Def_Id)) then
8128 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
8131 if Is_Tagged_Type (T) then
8132 Set_Is_Tagged_Type (Def_Id);
8133 Make_Class_Wide_Type (Def_Id);
8136 Set_Stored_Constraint (Def_Id, No_Elist);
8139 Set_Discriminant_Constraint (Def_Id, Elist);
8140 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
8143 if Is_Tagged_Type (T) then
8145 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
8146 -- concurrent record type (which has the list of primitive
8149 if Ada_Version >= Ada_05
8150 and then Is_Concurrent_Type (T)
8152 Set_Corresponding_Record_Type (Def_Id,
8153 Corresponding_Record_Type (T));
8155 Set_Primitive_Operations (Def_Id, Primitive_Operations (T));
8158 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
8161 -- Subtypes introduced by component declarations do not need to be
8162 -- marked as delayed, and do not get freeze nodes, because the semantics
8163 -- verifies that the parents of the subtypes are frozen before the
8164 -- enclosing record is frozen.
8166 if not Is_Type (Scope (Def_Id)) then
8167 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
8169 if Is_Private_Type (T)
8170 and then Present (Full_View (T))
8172 Conditional_Delay (Def_Id, Full_View (T));
8174 Conditional_Delay (Def_Id, T);
8178 if Is_Record_Type (T) then
8179 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
8182 and then not Is_Empty_Elmt_List (Elist)
8183 and then not For_Access
8185 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
8186 elsif not For_Access then
8187 Set_Cloned_Subtype (Def_Id, T);
8190 end Build_Discriminated_Subtype;
8192 ---------------------------
8193 -- Build_Itype_Reference --
8194 ---------------------------
8196 procedure Build_Itype_Reference
8200 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
8202 Set_Itype (IR, Ityp);
8203 Insert_After (Nod, IR);
8204 end Build_Itype_Reference;
8206 ------------------------
8207 -- Build_Scalar_Bound --
8208 ------------------------
8210 function Build_Scalar_Bound
8213 Der_T : Entity_Id) return Node_Id
8215 New_Bound : Entity_Id;
8218 -- Note: not clear why this is needed, how can the original bound
8219 -- be unanalyzed at this point? and if it is, what business do we
8220 -- have messing around with it? and why is the base type of the
8221 -- parent type the right type for the resolution. It probably is
8222 -- not! It is OK for the new bound we are creating, but not for
8223 -- the old one??? Still if it never happens, no problem!
8225 Analyze_And_Resolve (Bound, Base_Type (Par_T));
8227 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
8228 New_Bound := New_Copy (Bound);
8229 Set_Etype (New_Bound, Der_T);
8230 Set_Analyzed (New_Bound);
8232 elsif Is_Entity_Name (Bound) then
8233 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
8235 -- The following is almost certainly wrong. What business do we have
8236 -- relocating a node (Bound) that is presumably still attached to
8237 -- the tree elsewhere???
8240 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
8243 Set_Etype (New_Bound, Der_T);
8245 end Build_Scalar_Bound;
8247 --------------------------------
8248 -- Build_Underlying_Full_View --
8249 --------------------------------
8251 procedure Build_Underlying_Full_View
8256 Loc : constant Source_Ptr := Sloc (N);
8257 Subt : constant Entity_Id :=
8258 Make_Defining_Identifier
8259 (Loc, New_External_Name (Chars (Typ), 'S'));
8266 procedure Set_Discriminant_Name (Id : Node_Id);
8267 -- If the derived type has discriminants, they may rename discriminants
8268 -- of the parent. When building the full view of the parent, we need to
8269 -- recover the names of the original discriminants if the constraint is
8270 -- given by named associations.
8272 ---------------------------
8273 -- Set_Discriminant_Name --
8274 ---------------------------
8276 procedure Set_Discriminant_Name (Id : Node_Id) is
8280 Set_Original_Discriminant (Id, Empty);
8282 if Has_Discriminants (Typ) then
8283 Disc := First_Discriminant (Typ);
8284 while Present (Disc) loop
8285 if Chars (Disc) = Chars (Id)
8286 and then Present (Corresponding_Discriminant (Disc))
8288 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
8290 Next_Discriminant (Disc);
8293 end Set_Discriminant_Name;
8295 -- Start of processing for Build_Underlying_Full_View
8298 if Nkind (N) = N_Full_Type_Declaration then
8299 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
8301 elsif Nkind (N) = N_Subtype_Declaration then
8302 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
8304 elsif Nkind (N) = N_Component_Declaration then
8307 (Constraint (Subtype_Indication (Component_Definition (N))));
8310 raise Program_Error;
8313 C := First (Constraints (Constr));
8314 while Present (C) loop
8315 if Nkind (C) = N_Discriminant_Association then
8316 Id := First (Selector_Names (C));
8317 while Present (Id) loop
8318 Set_Discriminant_Name (Id);
8327 Make_Subtype_Declaration (Loc,
8328 Defining_Identifier => Subt,
8329 Subtype_Indication =>
8330 Make_Subtype_Indication (Loc,
8331 Subtype_Mark => New_Reference_To (Par, Loc),
8332 Constraint => New_Copy_Tree (Constr)));
8334 -- If this is a component subtype for an outer itype, it is not
8335 -- a list member, so simply set the parent link for analysis: if
8336 -- the enclosing type does not need to be in a declarative list,
8337 -- neither do the components.
8339 if Is_List_Member (N)
8340 and then Nkind (N) /= N_Component_Declaration
8342 Insert_Before (N, Indic);
8344 Set_Parent (Indic, Parent (N));
8348 Set_Underlying_Full_View (Typ, Full_View (Subt));
8349 end Build_Underlying_Full_View;
8351 -------------------------------
8352 -- Check_Abstract_Overriding --
8353 -------------------------------
8355 procedure Check_Abstract_Overriding (T : Entity_Id) is
8356 Alias_Subp : Entity_Id;
8363 Op_List := Primitive_Operations (T);
8365 -- Loop to check primitive operations
8367 Elmt := First_Elmt (Op_List);
8368 while Present (Elmt) loop
8369 Subp := Node (Elmt);
8370 Alias_Subp := Alias (Subp);
8372 -- Inherited subprograms are identified by the fact that they do not
8373 -- come from source, and the associated source location is the
8374 -- location of the first subtype of the derived type.
8376 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
8377 -- subprograms that "require overriding".
8379 -- Special exception, do not complain about failure to override the
8380 -- stream routines _Input and _Output, as well as the primitive
8381 -- operations used in dispatching selects since we always provide
8382 -- automatic overridings for these subprograms.
8384 -- Also ignore this rule for convention CIL since .NET libraries
8385 -- do bizarre things with interfaces???
8387 -- The partial view of T may have been a private extension, for
8388 -- which inherited functions dispatching on result are abstract.
8389 -- If the full view is a null extension, there is no need for
8390 -- overriding in Ada2005, but wrappers need to be built for them
8391 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
8393 if Is_Null_Extension (T)
8394 and then Has_Controlling_Result (Subp)
8395 and then Ada_Version >= Ada_05
8396 and then Present (Alias_Subp)
8397 and then not Comes_From_Source (Subp)
8398 and then not Is_Abstract_Subprogram (Alias_Subp)
8399 and then not Is_Access_Type (Etype (Subp))
8403 -- Ada 2005 (AI-251): Internal entities of interfaces need no
8404 -- processing because this check is done with the aliased
8407 elsif Present (Interface_Alias (Subp)) then
8410 elsif (Is_Abstract_Subprogram (Subp)
8411 or else Requires_Overriding (Subp)
8413 (Has_Controlling_Result (Subp)
8414 and then Present (Alias_Subp)
8415 and then not Comes_From_Source (Subp)
8416 and then Sloc (Subp) = Sloc (First_Subtype (T))))
8417 and then not Is_TSS (Subp, TSS_Stream_Input)
8418 and then not Is_TSS (Subp, TSS_Stream_Output)
8419 and then not Is_Abstract_Type (T)
8420 and then Convention (T) /= Convention_CIL
8421 and then not Is_Predefined_Interface_Primitive (Subp)
8423 -- Ada 2005 (AI-251): Do not consider hidden entities associated
8424 -- with abstract interface types because the check will be done
8425 -- with the aliased entity (otherwise we generate a duplicated
8428 and then not Present (Interface_Alias (Subp))
8430 if Present (Alias_Subp) then
8432 -- Only perform the check for a derived subprogram when the
8433 -- type has an explicit record extension. This avoids incorrect
8434 -- flagging of abstract subprograms for the case of a type
8435 -- without an extension that is derived from a formal type
8436 -- with a tagged actual (can occur within a private part).
8438 -- Ada 2005 (AI-391): In the case of an inherited function with
8439 -- a controlling result of the type, the rule does not apply if
8440 -- the type is a null extension (unless the parent function
8441 -- itself is abstract, in which case the function must still be
8442 -- be overridden). The expander will generate an overriding
8443 -- wrapper function calling the parent subprogram (see
8444 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
8446 Type_Def := Type_Definition (Parent (T));
8448 if Nkind (Type_Def) = N_Derived_Type_Definition
8449 and then Present (Record_Extension_Part (Type_Def))
8451 (Ada_Version < Ada_05
8452 or else not Is_Null_Extension (T)
8453 or else Ekind (Subp) = E_Procedure
8454 or else not Has_Controlling_Result (Subp)
8455 or else Is_Abstract_Subprogram (Alias_Subp)
8456 or else Requires_Overriding (Subp)
8457 or else Is_Access_Type (Etype (Subp)))
8459 -- Avoid reporting error in case of abstract predefined
8460 -- primitive inherited from interface type because the
8461 -- body of internally generated predefined primitives
8462 -- of tagged types are generated later by Freeze_Type
8464 if Is_Interface (Root_Type (T))
8465 and then Is_Abstract_Subprogram (Subp)
8466 and then Is_Predefined_Dispatching_Operation (Subp)
8467 and then not Comes_From_Source (Ultimate_Alias (Subp))
8473 ("type must be declared abstract or & overridden",
8476 -- Traverse the whole chain of aliased subprograms to
8477 -- complete the error notification. This is especially
8478 -- useful for traceability of the chain of entities when
8479 -- the subprogram corresponds with an interface
8480 -- subprogram (which may be defined in another package).
8482 if Present (Alias_Subp) then
8488 while Present (Alias (E)) loop
8489 Error_Msg_Sloc := Sloc (E);
8491 ("\& has been inherited #", T, Subp);
8495 Error_Msg_Sloc := Sloc (E);
8497 ("\& has been inherited from subprogram #",
8503 -- Ada 2005 (AI-345): Protected or task type implementing
8504 -- abstract interfaces.
8506 elsif Is_Concurrent_Record_Type (T)
8507 and then Present (Interfaces (T))
8509 -- The controlling formal of Subp must be of mode "out",
8510 -- "in out" or an access-to-variable to be overridden.
8512 -- Error message below needs rewording (remember comma
8513 -- in -gnatj mode) ???
8515 if Ekind (First_Formal (Subp)) = E_In_Parameter
8516 and then Ekind (Subp) /= E_Function
8518 if not Is_Predefined_Dispatching_Operation (Subp) then
8520 ("first formal of & must be of mode `OUT`, " &
8521 "`IN OUT` or access-to-variable", T, Subp);
8523 ("\to be overridden by protected procedure or " &
8524 "entry (RM 9.4(11.9/2))", T);
8527 -- Some other kind of overriding failure
8531 ("interface subprogram & must be overridden",
8534 -- Examine primitive operations of synchronized type,
8535 -- to find homonyms that have the wrong profile.
8542 First_Entity (Corresponding_Concurrent_Type (T));
8543 while Present (Prim) loop
8544 if Chars (Prim) = Chars (Subp) then
8546 ("profile is not type conformant with "
8547 & "prefixed view profile of "
8548 & "inherited operation&", Prim, Subp);
8558 Error_Msg_Node_2 := T;
8560 ("abstract subprogram& not allowed for type&", Subp);
8562 -- Also post unconditional warning on the type (unconditional
8563 -- so that if there are more than one of these cases, we get
8564 -- them all, and not just the first one).
8566 Error_Msg_Node_2 := Subp;
8568 ("nonabstract type& has abstract subprogram&!", T);
8572 -- Ada 2005 (AI05-0030): Inspect hidden subprograms which provide
8573 -- the mapping between interface and implementing type primitives.
8574 -- If the interface alias is marked as Implemented_By_Entry, the
8575 -- alias must be an entry wrapper.
8577 if Ada_Version >= Ada_05
8578 and then Is_Hidden (Subp)
8579 and then Present (Interface_Alias (Subp))
8580 and then Implemented_By_Entry (Interface_Alias (Subp))
8581 and then Present (Alias_Subp)
8583 (not Is_Primitive_Wrapper (Alias_Subp)
8584 or else Ekind (Wrapped_Entity (Alias_Subp)) /= E_Entry)
8587 Error_Ent : Entity_Id := T;
8590 if Is_Concurrent_Record_Type (Error_Ent) then
8591 Error_Ent := Corresponding_Concurrent_Type (Error_Ent);
8594 Error_Msg_Node_2 := Interface_Alias (Subp);
8596 ("type & must implement abstract subprogram & with an entry",
8597 Error_Ent, Error_Ent);
8603 end Check_Abstract_Overriding;
8605 ------------------------------------------------
8606 -- Check_Access_Discriminant_Requires_Limited --
8607 ------------------------------------------------
8609 procedure Check_Access_Discriminant_Requires_Limited
8614 -- A discriminant_specification for an access discriminant shall appear
8615 -- only in the declaration for a task or protected type, or for a type
8616 -- with the reserved word 'limited' in its definition or in one of its
8617 -- ancestors. (RM 3.7(10))
8619 if Nkind (Discriminant_Type (D)) = N_Access_Definition
8620 and then not Is_Concurrent_Type (Current_Scope)
8621 and then not Is_Concurrent_Record_Type (Current_Scope)
8622 and then not Is_Limited_Record (Current_Scope)
8623 and then Ekind (Current_Scope) /= E_Limited_Private_Type
8626 ("access discriminants allowed only for limited types", Loc);
8628 end Check_Access_Discriminant_Requires_Limited;
8630 -----------------------------------
8631 -- Check_Aliased_Component_Types --
8632 -----------------------------------
8634 procedure Check_Aliased_Component_Types (T : Entity_Id) is
8638 -- ??? Also need to check components of record extensions, but not
8639 -- components of protected types (which are always limited).
8641 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
8642 -- types to be unconstrained. This is safe because it is illegal to
8643 -- create access subtypes to such types with explicit discriminant
8646 if not Is_Limited_Type (T) then
8647 if Ekind (T) = E_Record_Type then
8648 C := First_Component (T);
8649 while Present (C) loop
8651 and then Has_Discriminants (Etype (C))
8652 and then not Is_Constrained (Etype (C))
8653 and then not In_Instance_Body
8654 and then Ada_Version < Ada_05
8657 ("aliased component must be constrained (RM 3.6(11))",
8664 elsif Ekind (T) = E_Array_Type then
8665 if Has_Aliased_Components (T)
8666 and then Has_Discriminants (Component_Type (T))
8667 and then not Is_Constrained (Component_Type (T))
8668 and then not In_Instance_Body
8669 and then Ada_Version < Ada_05
8672 ("aliased component type must be constrained (RM 3.6(11))",
8677 end Check_Aliased_Component_Types;
8679 ----------------------
8680 -- Check_Completion --
8681 ----------------------
8683 procedure Check_Completion (Body_Id : Node_Id := Empty) is
8686 procedure Post_Error;
8687 -- Post error message for lack of completion for entity E
8693 procedure Post_Error is
8695 procedure Missing_Body;
8696 -- Output missing body message
8702 procedure Missing_Body is
8704 -- Spec is in same unit, so we can post on spec
8706 if In_Same_Source_Unit (Body_Id, E) then
8707 Error_Msg_N ("missing body for &", E);
8709 -- Spec is in a separate unit, so we have to post on the body
8712 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
8716 -- Start of processing for Post_Error
8719 if not Comes_From_Source (E) then
8721 if Ekind (E) = E_Task_Type
8722 or else Ekind (E) = E_Protected_Type
8724 -- It may be an anonymous protected type created for a
8725 -- single variable. Post error on variable, if present.
8731 Var := First_Entity (Current_Scope);
8732 while Present (Var) loop
8733 exit when Etype (Var) = E
8734 and then Comes_From_Source (Var);
8739 if Present (Var) then
8746 -- If a generated entity has no completion, then either previous
8747 -- semantic errors have disabled the expansion phase, or else we had
8748 -- missing subunits, or else we are compiling without expansion,
8749 -- or else something is very wrong.
8751 if not Comes_From_Source (E) then
8753 (Serious_Errors_Detected > 0
8754 or else Configurable_Run_Time_Violations > 0
8755 or else Subunits_Missing
8756 or else not Expander_Active);
8759 -- Here for source entity
8762 -- Here if no body to post the error message, so we post the error
8763 -- on the declaration that has no completion. This is not really
8764 -- the right place to post it, think about this later ???
8766 if No (Body_Id) then
8769 ("missing full declaration for }", Parent (E), E);
8772 ("missing body for &", Parent (E), E);
8775 -- Package body has no completion for a declaration that appears
8776 -- in the corresponding spec. Post error on the body, with a
8777 -- reference to the non-completed declaration.
8780 Error_Msg_Sloc := Sloc (E);
8784 ("missing full declaration for }!", Body_Id, E);
8786 elsif Is_Overloadable (E)
8787 and then Current_Entity_In_Scope (E) /= E
8789 -- It may be that the completion is mistyped and appears as
8790 -- a distinct overloading of the entity.
8793 Candidate : constant Entity_Id :=
8794 Current_Entity_In_Scope (E);
8795 Decl : constant Node_Id :=
8796 Unit_Declaration_Node (Candidate);
8799 if Is_Overloadable (Candidate)
8800 and then Ekind (Candidate) = Ekind (E)
8801 and then Nkind (Decl) = N_Subprogram_Body
8802 and then Acts_As_Spec (Decl)
8804 Check_Type_Conformant (Candidate, E);
8818 -- Start of processing for Check_Completion
8821 E := First_Entity (Current_Scope);
8822 while Present (E) loop
8823 if Is_Intrinsic_Subprogram (E) then
8826 -- The following situation requires special handling: a child unit
8827 -- that appears in the context clause of the body of its parent:
8829 -- procedure Parent.Child (...);
8831 -- with Parent.Child;
8832 -- package body Parent is
8834 -- Here Parent.Child appears as a local entity, but should not be
8835 -- flagged as requiring completion, because it is a compilation
8838 -- Ignore missing completion for a subprogram that does not come from
8839 -- source (including the _Call primitive operation of RAS types,
8840 -- which has to have the flag Comes_From_Source for other purposes):
8841 -- we assume that the expander will provide the missing completion.
8842 -- In case of previous errors, other expansion actions that provide
8843 -- bodies for null procedures with not be invoked, so inhibit message
8845 -- Note that E_Operator is not in the list that follows, because
8846 -- this kind is reserved for predefined operators, that are
8847 -- intrinsic and do not need completion.
8849 elsif Ekind (E) = E_Function
8850 or else Ekind (E) = E_Procedure
8851 or else Ekind (E) = E_Generic_Function
8852 or else Ekind (E) = E_Generic_Procedure
8854 if Has_Completion (E) then
8857 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
8860 elsif Is_Subprogram (E)
8861 and then (not Comes_From_Source (E)
8862 or else Chars (E) = Name_uCall)
8867 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
8871 elsif Nkind (Parent (E)) = N_Procedure_Specification
8872 and then Null_Present (Parent (E))
8873 and then Serious_Errors_Detected > 0
8881 elsif Is_Entry (E) then
8882 if not Has_Completion (E) and then
8883 (Ekind (Scope (E)) = E_Protected_Object
8884 or else Ekind (Scope (E)) = E_Protected_Type)
8889 elsif Is_Package_Or_Generic_Package (E) then
8890 if Unit_Requires_Body (E) then
8891 if not Has_Completion (E)
8892 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
8898 elsif not Is_Child_Unit (E) then
8899 May_Need_Implicit_Body (E);
8902 elsif Ekind (E) = E_Incomplete_Type
8903 and then No (Underlying_Type (E))
8907 elsif (Ekind (E) = E_Task_Type or else
8908 Ekind (E) = E_Protected_Type)
8909 and then not Has_Completion (E)
8913 -- A single task declared in the current scope is a constant, verify
8914 -- that the body of its anonymous type is in the same scope. If the
8915 -- task is defined elsewhere, this may be a renaming declaration for
8916 -- which no completion is needed.
8918 elsif Ekind (E) = E_Constant
8919 and then Ekind (Etype (E)) = E_Task_Type
8920 and then not Has_Completion (Etype (E))
8921 and then Scope (Etype (E)) = Current_Scope
8925 elsif Ekind (E) = E_Protected_Object
8926 and then not Has_Completion (Etype (E))
8930 elsif Ekind (E) = E_Record_Type then
8931 if Is_Tagged_Type (E) then
8932 Check_Abstract_Overriding (E);
8933 Check_Conventions (E);
8936 Check_Aliased_Component_Types (E);
8938 elsif Ekind (E) = E_Array_Type then
8939 Check_Aliased_Component_Types (E);
8945 end Check_Completion;
8947 ----------------------------
8948 -- Check_Delta_Expression --
8949 ----------------------------
8951 procedure Check_Delta_Expression (E : Node_Id) is
8953 if not (Is_Real_Type (Etype (E))) then
8954 Wrong_Type (E, Any_Real);
8956 elsif not Is_OK_Static_Expression (E) then
8957 Flag_Non_Static_Expr
8958 ("non-static expression used for delta value!", E);
8960 elsif not UR_Is_Positive (Expr_Value_R (E)) then
8961 Error_Msg_N ("delta expression must be positive", E);
8967 -- If any of above errors occurred, then replace the incorrect
8968 -- expression by the real 0.1, which should prevent further errors.
8971 Make_Real_Literal (Sloc (E), Ureal_Tenth));
8972 Analyze_And_Resolve (E, Standard_Float);
8973 end Check_Delta_Expression;
8975 -----------------------------
8976 -- Check_Digits_Expression --
8977 -----------------------------
8979 procedure Check_Digits_Expression (E : Node_Id) is
8981 if not (Is_Integer_Type (Etype (E))) then
8982 Wrong_Type (E, Any_Integer);
8984 elsif not Is_OK_Static_Expression (E) then
8985 Flag_Non_Static_Expr
8986 ("non-static expression used for digits value!", E);
8988 elsif Expr_Value (E) <= 0 then
8989 Error_Msg_N ("digits value must be greater than zero", E);
8995 -- If any of above errors occurred, then replace the incorrect
8996 -- expression by the integer 1, which should prevent further errors.
8998 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
8999 Analyze_And_Resolve (E, Standard_Integer);
9001 end Check_Digits_Expression;
9003 --------------------------
9004 -- Check_Initialization --
9005 --------------------------
9007 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
9009 if Is_Limited_Type (T)
9010 and then not In_Instance
9011 and then not In_Inlined_Body
9013 if not OK_For_Limited_Init (T, Exp) then
9015 -- In GNAT mode, this is just a warning, to allow it to be evilly
9016 -- turned off. Otherwise it is a real error.
9020 ("?cannot initialize entities of limited type!", Exp);
9022 elsif Ada_Version < Ada_05 then
9024 ("cannot initialize entities of limited type", Exp);
9025 Explain_Limited_Type (T, Exp);
9028 -- Specialize error message according to kind of illegal
9029 -- initial expression.
9031 if Nkind (Exp) = N_Type_Conversion
9032 and then Nkind (Expression (Exp)) = N_Function_Call
9035 ("illegal context for call"
9036 & " to function with limited result", Exp);
9040 ("initialization of limited object requires aggregate "
9041 & "or function call", Exp);
9046 end Check_Initialization;
9048 ----------------------
9049 -- Check_Interfaces --
9050 ----------------------
9052 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
9053 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
9056 Iface_Def : Node_Id;
9057 Iface_Typ : Entity_Id;
9058 Parent_Node : Node_Id;
9060 Is_Task : Boolean := False;
9061 -- Set True if parent type or any progenitor is a task interface
9063 Is_Protected : Boolean := False;
9064 -- Set True if parent type or any progenitor is a protected interface
9066 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
9067 -- Check that a progenitor is compatible with declaration.
9068 -- Error is posted on Error_Node.
9074 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
9075 Iface_Id : constant Entity_Id :=
9076 Defining_Identifier (Parent (Iface_Def));
9080 if Nkind (N) = N_Private_Extension_Declaration then
9083 Type_Def := Type_Definition (N);
9086 if Is_Task_Interface (Iface_Id) then
9089 elsif Is_Protected_Interface (Iface_Id) then
9090 Is_Protected := True;
9093 if Is_Synchronized_Interface (Iface_Id) then
9095 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
9096 -- extension derived from a synchronized interface must explicitly
9097 -- be declared synchronized, because the full view will be a
9098 -- synchronized type.
9100 if Nkind (N) = N_Private_Extension_Declaration then
9101 if not Synchronized_Present (N) then
9103 ("private extension of& must be explicitly synchronized",
9107 -- However, by 3.9.4(16/2), a full type that is a record extension
9108 -- is never allowed to derive from a synchronized interface (note
9109 -- that interfaces must be excluded from this check, because those
9110 -- are represented by derived type definitions in some cases).
9112 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9113 and then not Interface_Present (Type_Definition (N))
9115 Error_Msg_N ("record extension cannot derive from synchronized"
9116 & " interface", Error_Node);
9120 -- Check that the characteristics of the progenitor are compatible
9121 -- with the explicit qualifier in the declaration.
9122 -- The check only applies to qualifiers that come from source.
9123 -- Limited_Present also appears in the declaration of corresponding
9124 -- records, and the check does not apply to them.
9126 if Limited_Present (Type_Def)
9128 Is_Concurrent_Record_Type (Defining_Identifier (N))
9130 if Is_Limited_Interface (Parent_Type)
9131 and then not Is_Limited_Interface (Iface_Id)
9134 ("progenitor& must be limited interface",
9135 Error_Node, Iface_Id);
9138 (Task_Present (Iface_Def)
9139 or else Protected_Present (Iface_Def)
9140 or else Synchronized_Present (Iface_Def))
9141 and then Nkind (N) /= N_Private_Extension_Declaration
9142 and then not Error_Posted (N)
9145 ("progenitor& must be limited interface",
9146 Error_Node, Iface_Id);
9149 -- Protected interfaces can only inherit from limited, synchronized
9150 -- or protected interfaces.
9152 elsif Nkind (N) = N_Full_Type_Declaration
9153 and then Protected_Present (Type_Def)
9155 if Limited_Present (Iface_Def)
9156 or else Synchronized_Present (Iface_Def)
9157 or else Protected_Present (Iface_Def)
9161 elsif Task_Present (Iface_Def) then
9162 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9163 & " from task interface", Error_Node);
9166 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9167 & " from non-limited interface", Error_Node);
9170 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
9171 -- limited and synchronized.
9173 elsif Synchronized_Present (Type_Def) then
9174 if Limited_Present (Iface_Def)
9175 or else Synchronized_Present (Iface_Def)
9179 elsif Protected_Present (Iface_Def)
9180 and then Nkind (N) /= N_Private_Extension_Declaration
9182 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9183 & " from protected interface", Error_Node);
9185 elsif Task_Present (Iface_Def)
9186 and then Nkind (N) /= N_Private_Extension_Declaration
9188 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9189 & " from task interface", Error_Node);
9191 elsif not Is_Limited_Interface (Iface_Id) then
9192 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9193 & " from non-limited interface", Error_Node);
9196 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
9197 -- synchronized or task interfaces.
9199 elsif Nkind (N) = N_Full_Type_Declaration
9200 and then Task_Present (Type_Def)
9202 if Limited_Present (Iface_Def)
9203 or else Synchronized_Present (Iface_Def)
9204 or else Task_Present (Iface_Def)
9208 elsif Protected_Present (Iface_Def) then
9209 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9210 & " protected interface", Error_Node);
9213 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9214 & " non-limited interface", Error_Node);
9219 -- Start of processing for Check_Interfaces
9222 if Is_Interface (Parent_Type) then
9223 if Is_Task_Interface (Parent_Type) then
9226 elsif Is_Protected_Interface (Parent_Type) then
9227 Is_Protected := True;
9231 if Nkind (N) = N_Private_Extension_Declaration then
9233 -- Check that progenitors are compatible with declaration
9235 Iface := First (Interface_List (Def));
9236 while Present (Iface) loop
9237 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9239 Parent_Node := Parent (Base_Type (Iface_Typ));
9240 Iface_Def := Type_Definition (Parent_Node);
9242 if not Is_Interface (Iface_Typ) then
9243 Diagnose_Interface (Iface, Iface_Typ);
9246 Check_Ifaces (Iface_Def, Iface);
9252 if Is_Task and Is_Protected then
9254 ("type cannot derive from task and protected interface", N);
9260 -- Full type declaration of derived type.
9261 -- Check compatibility with parent if it is interface type
9263 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9264 and then Is_Interface (Parent_Type)
9266 Parent_Node := Parent (Parent_Type);
9268 -- More detailed checks for interface varieties
9271 (Iface_Def => Type_Definition (Parent_Node),
9272 Error_Node => Subtype_Indication (Type_Definition (N)));
9275 Iface := First (Interface_List (Def));
9276 while Present (Iface) loop
9277 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9279 Parent_Node := Parent (Base_Type (Iface_Typ));
9280 Iface_Def := Type_Definition (Parent_Node);
9282 if not Is_Interface (Iface_Typ) then
9283 Diagnose_Interface (Iface, Iface_Typ);
9286 -- "The declaration of a specific descendant of an interface
9287 -- type freezes the interface type" RM 13.14
9289 Freeze_Before (N, Iface_Typ);
9290 Check_Ifaces (Iface_Def, Error_Node => Iface);
9296 if Is_Task and Is_Protected then
9298 ("type cannot derive from task and protected interface", N);
9300 end Check_Interfaces;
9302 ------------------------------------
9303 -- Check_Or_Process_Discriminants --
9304 ------------------------------------
9306 -- If an incomplete or private type declaration was already given for the
9307 -- type, the discriminants may have already been processed if they were
9308 -- present on the incomplete declaration. In this case a full conformance
9309 -- check is performed otherwise just process them.
9311 procedure Check_Or_Process_Discriminants
9314 Prev : Entity_Id := Empty)
9317 if Has_Discriminants (T) then
9319 -- Make the discriminants visible to component declarations
9326 D := First_Discriminant (T);
9327 while Present (D) loop
9328 Prev := Current_Entity (D);
9329 Set_Current_Entity (D);
9330 Set_Is_Immediately_Visible (D);
9331 Set_Homonym (D, Prev);
9333 -- Ada 2005 (AI-230): Access discriminant allowed in
9334 -- non-limited record types.
9336 if Ada_Version < Ada_05 then
9338 -- This restriction gets applied to the full type here. It
9339 -- has already been applied earlier to the partial view.
9341 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
9344 Next_Discriminant (D);
9348 elsif Present (Discriminant_Specifications (N)) then
9349 Process_Discriminants (N, Prev);
9351 end Check_Or_Process_Discriminants;
9353 ----------------------
9354 -- Check_Real_Bound --
9355 ----------------------
9357 procedure Check_Real_Bound (Bound : Node_Id) is
9359 if not Is_Real_Type (Etype (Bound)) then
9361 ("bound in real type definition must be of real type", Bound);
9363 elsif not Is_OK_Static_Expression (Bound) then
9364 Flag_Non_Static_Expr
9365 ("non-static expression used for real type bound!", Bound);
9372 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
9374 Resolve (Bound, Standard_Float);
9375 end Check_Real_Bound;
9377 ------------------------------
9378 -- Complete_Private_Subtype --
9379 ------------------------------
9381 procedure Complete_Private_Subtype
9384 Full_Base : Entity_Id;
9385 Related_Nod : Node_Id)
9387 Save_Next_Entity : Entity_Id;
9388 Save_Homonym : Entity_Id;
9391 -- Set semantic attributes for (implicit) private subtype completion.
9392 -- If the full type has no discriminants, then it is a copy of the full
9393 -- view of the base. Otherwise, it is a subtype of the base with a
9394 -- possible discriminant constraint. Save and restore the original
9395 -- Next_Entity field of full to ensure that the calls to Copy_Node
9396 -- do not corrupt the entity chain.
9398 -- Note that the type of the full view is the same entity as the type of
9399 -- the partial view. In this fashion, the subtype has access to the
9400 -- correct view of the parent.
9402 Save_Next_Entity := Next_Entity (Full);
9403 Save_Homonym := Homonym (Priv);
9405 case Ekind (Full_Base) is
9406 when E_Record_Type |
9412 Copy_Node (Priv, Full);
9414 Set_Has_Discriminants (Full, Has_Discriminants (Full_Base));
9415 Set_First_Entity (Full, First_Entity (Full_Base));
9416 Set_Last_Entity (Full, Last_Entity (Full_Base));
9419 Copy_Node (Full_Base, Full);
9420 Set_Chars (Full, Chars (Priv));
9421 Conditional_Delay (Full, Priv);
9422 Set_Sloc (Full, Sloc (Priv));
9425 Set_Next_Entity (Full, Save_Next_Entity);
9426 Set_Homonym (Full, Save_Homonym);
9427 Set_Associated_Node_For_Itype (Full, Related_Nod);
9429 -- Set common attributes for all subtypes
9431 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
9433 -- The Etype of the full view is inconsistent. Gigi needs to see the
9434 -- structural full view, which is what the current scheme gives:
9435 -- the Etype of the full view is the etype of the full base. However,
9436 -- if the full base is a derived type, the full view then looks like
9437 -- a subtype of the parent, not a subtype of the full base. If instead
9440 -- Set_Etype (Full, Full_Base);
9442 -- then we get inconsistencies in the front-end (confusion between
9443 -- views). Several outstanding bugs are related to this ???
9445 Set_Is_First_Subtype (Full, False);
9446 Set_Scope (Full, Scope (Priv));
9447 Set_Size_Info (Full, Full_Base);
9448 Set_RM_Size (Full, RM_Size (Full_Base));
9449 Set_Is_Itype (Full);
9451 -- A subtype of a private-type-without-discriminants, whose full-view
9452 -- has discriminants with default expressions, is not constrained!
9454 if not Has_Discriminants (Priv) then
9455 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
9457 if Has_Discriminants (Full_Base) then
9458 Set_Discriminant_Constraint
9459 (Full, Discriminant_Constraint (Full_Base));
9461 -- The partial view may have been indefinite, the full view
9464 Set_Has_Unknown_Discriminants
9465 (Full, Has_Unknown_Discriminants (Full_Base));
9469 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
9470 Set_Depends_On_Private (Full, Has_Private_Component (Full));
9472 -- Freeze the private subtype entity if its parent is delayed, and not
9473 -- already frozen. We skip this processing if the type is an anonymous
9474 -- subtype of a record component, or is the corresponding record of a
9475 -- protected type, since ???
9477 if not Is_Type (Scope (Full)) then
9478 Set_Has_Delayed_Freeze (Full,
9479 Has_Delayed_Freeze (Full_Base)
9480 and then (not Is_Frozen (Full_Base)));
9483 Set_Freeze_Node (Full, Empty);
9484 Set_Is_Frozen (Full, False);
9485 Set_Full_View (Priv, Full);
9487 if Has_Discriminants (Full) then
9488 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
9489 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
9491 if Has_Unknown_Discriminants (Full) then
9492 Set_Discriminant_Constraint (Full, No_Elist);
9496 if Ekind (Full_Base) = E_Record_Type
9497 and then Has_Discriminants (Full_Base)
9498 and then Has_Discriminants (Priv) -- might not, if errors
9499 and then not Has_Unknown_Discriminants (Priv)
9500 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
9502 Create_Constrained_Components
9503 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
9505 -- If the full base is itself derived from private, build a congruent
9506 -- subtype of its underlying type, for use by the back end. For a
9507 -- constrained record component, the declaration cannot be placed on
9508 -- the component list, but it must nevertheless be built an analyzed, to
9509 -- supply enough information for Gigi to compute the size of component.
9511 elsif Ekind (Full_Base) in Private_Kind
9512 and then Is_Derived_Type (Full_Base)
9513 and then Has_Discriminants (Full_Base)
9514 and then (Ekind (Current_Scope) /= E_Record_Subtype)
9516 if not Is_Itype (Priv)
9518 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
9520 Build_Underlying_Full_View
9521 (Parent (Priv), Full, Etype (Full_Base));
9523 elsif Nkind (Related_Nod) = N_Component_Declaration then
9524 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
9527 elsif Is_Record_Type (Full_Base) then
9529 -- Show Full is simply a renaming of Full_Base
9531 Set_Cloned_Subtype (Full, Full_Base);
9534 -- It is unsafe to share to bounds of a scalar type, because the Itype
9535 -- is elaborated on demand, and if a bound is non-static then different
9536 -- orders of elaboration in different units will lead to different
9537 -- external symbols.
9539 if Is_Scalar_Type (Full_Base) then
9540 Set_Scalar_Range (Full,
9541 Make_Range (Sloc (Related_Nod),
9543 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
9545 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
9547 -- This completion inherits the bounds of the full parent, but if
9548 -- the parent is an unconstrained floating point type, so is the
9551 if Is_Floating_Point_Type (Full_Base) then
9552 Set_Includes_Infinities
9553 (Scalar_Range (Full), Has_Infinities (Full_Base));
9557 -- ??? It seems that a lot of fields are missing that should be copied
9558 -- from Full_Base to Full. Here are some that are introduced in a
9559 -- non-disruptive way but a cleanup is necessary.
9561 if Is_Tagged_Type (Full_Base) then
9562 Set_Is_Tagged_Type (Full);
9563 Set_Primitive_Operations (Full, Primitive_Operations (Full_Base));
9564 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
9566 -- If this is a subtype of a protected or task type, constrain its
9567 -- corresponding record, unless this is a subtype without constraints,
9568 -- i.e. a simple renaming as with an actual subtype in an instance.
9570 elsif Is_Concurrent_Type (Full_Base) then
9571 if Has_Discriminants (Full)
9572 and then Present (Corresponding_Record_Type (Full_Base))
9574 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
9576 Set_Corresponding_Record_Type (Full,
9577 Constrain_Corresponding_Record
9578 (Full, Corresponding_Record_Type (Full_Base),
9579 Related_Nod, Full_Base));
9582 Set_Corresponding_Record_Type (Full,
9583 Corresponding_Record_Type (Full_Base));
9586 end Complete_Private_Subtype;
9588 ----------------------------
9589 -- Constant_Redeclaration --
9590 ----------------------------
9592 procedure Constant_Redeclaration
9597 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
9598 Obj_Def : constant Node_Id := Object_Definition (N);
9601 procedure Check_Possible_Deferred_Completion
9602 (Prev_Id : Entity_Id;
9603 Prev_Obj_Def : Node_Id;
9604 Curr_Obj_Def : Node_Id);
9605 -- Determine whether the two object definitions describe the partial
9606 -- and the full view of a constrained deferred constant. Generate
9607 -- a subtype for the full view and verify that it statically matches
9608 -- the subtype of the partial view.
9610 procedure Check_Recursive_Declaration (Typ : Entity_Id);
9611 -- If deferred constant is an access type initialized with an allocator,
9612 -- check whether there is an illegal recursion in the definition,
9613 -- through a default value of some record subcomponent. This is normally
9614 -- detected when generating init procs, but requires this additional
9615 -- mechanism when expansion is disabled.
9617 ----------------------------------------
9618 -- Check_Possible_Deferred_Completion --
9619 ----------------------------------------
9621 procedure Check_Possible_Deferred_Completion
9622 (Prev_Id : Entity_Id;
9623 Prev_Obj_Def : Node_Id;
9624 Curr_Obj_Def : Node_Id)
9627 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
9628 and then Present (Constraint (Prev_Obj_Def))
9629 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
9630 and then Present (Constraint (Curr_Obj_Def))
9633 Loc : constant Source_Ptr := Sloc (N);
9634 Def_Id : constant Entity_Id :=
9635 Make_Defining_Identifier (Loc,
9636 New_Internal_Name ('S'));
9637 Decl : constant Node_Id :=
9638 Make_Subtype_Declaration (Loc,
9639 Defining_Identifier =>
9641 Subtype_Indication =>
9642 Relocate_Node (Curr_Obj_Def));
9645 Insert_Before_And_Analyze (N, Decl);
9646 Set_Etype (Id, Def_Id);
9648 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
9649 Error_Msg_Sloc := Sloc (Prev_Id);
9650 Error_Msg_N ("subtype does not statically match deferred " &
9655 end Check_Possible_Deferred_Completion;
9657 ---------------------------------
9658 -- Check_Recursive_Declaration --
9659 ---------------------------------
9661 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
9665 if Is_Record_Type (Typ) then
9666 Comp := First_Component (Typ);
9667 while Present (Comp) loop
9668 if Comes_From_Source (Comp) then
9669 if Present (Expression (Parent (Comp)))
9670 and then Is_Entity_Name (Expression (Parent (Comp)))
9671 and then Entity (Expression (Parent (Comp))) = Prev
9673 Error_Msg_Sloc := Sloc (Parent (Comp));
9675 ("illegal circularity with declaration for&#",
9679 elsif Is_Record_Type (Etype (Comp)) then
9680 Check_Recursive_Declaration (Etype (Comp));
9684 Next_Component (Comp);
9687 end Check_Recursive_Declaration;
9689 -- Start of processing for Constant_Redeclaration
9692 if Nkind (Parent (Prev)) = N_Object_Declaration then
9693 if Nkind (Object_Definition
9694 (Parent (Prev))) = N_Subtype_Indication
9696 -- Find type of new declaration. The constraints of the two
9697 -- views must match statically, but there is no point in
9698 -- creating an itype for the full view.
9700 if Nkind (Obj_Def) = N_Subtype_Indication then
9701 Find_Type (Subtype_Mark (Obj_Def));
9702 New_T := Entity (Subtype_Mark (Obj_Def));
9705 Find_Type (Obj_Def);
9706 New_T := Entity (Obj_Def);
9712 -- The full view may impose a constraint, even if the partial
9713 -- view does not, so construct the subtype.
9715 New_T := Find_Type_Of_Object (Obj_Def, N);
9720 -- Current declaration is illegal, diagnosed below in Enter_Name
9726 -- If previous full declaration exists, or if a homograph is present,
9727 -- let Enter_Name handle it, either with an error, or with the removal
9728 -- of an overridden implicit subprogram.
9730 if Ekind (Prev) /= E_Constant
9731 or else Present (Expression (Parent (Prev)))
9732 or else Present (Full_View (Prev))
9736 -- Verify that types of both declarations match, or else that both types
9737 -- are anonymous access types whose designated subtypes statically match
9738 -- (as allowed in Ada 2005 by AI-385).
9740 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
9742 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
9743 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
9744 or else Is_Access_Constant (Etype (New_T)) /=
9745 Is_Access_Constant (Etype (Prev))
9746 or else Can_Never_Be_Null (Etype (New_T)) /=
9747 Can_Never_Be_Null (Etype (Prev))
9748 or else Null_Exclusion_Present (Parent (Prev)) /=
9749 Null_Exclusion_Present (Parent (Id))
9750 or else not Subtypes_Statically_Match
9751 (Designated_Type (Etype (Prev)),
9752 Designated_Type (Etype (New_T))))
9754 Error_Msg_Sloc := Sloc (Prev);
9755 Error_Msg_N ("type does not match declaration#", N);
9756 Set_Full_View (Prev, Id);
9757 Set_Etype (Id, Any_Type);
9760 Null_Exclusion_Present (Parent (Prev))
9761 and then not Null_Exclusion_Present (N)
9763 Error_Msg_Sloc := Sloc (Prev);
9764 Error_Msg_N ("null-exclusion does not match declaration#", N);
9765 Set_Full_View (Prev, Id);
9766 Set_Etype (Id, Any_Type);
9768 -- If so, process the full constant declaration
9771 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
9772 -- the deferred declaration is constrained, then the subtype defined
9773 -- by the subtype_indication in the full declaration shall match it
9776 Check_Possible_Deferred_Completion
9778 Prev_Obj_Def => Object_Definition (Parent (Prev)),
9779 Curr_Obj_Def => Obj_Def);
9781 Set_Full_View (Prev, Id);
9782 Set_Is_Public (Id, Is_Public (Prev));
9783 Set_Is_Internal (Id);
9784 Append_Entity (Id, Current_Scope);
9786 -- Check ALIASED present if present before (RM 7.4(7))
9788 if Is_Aliased (Prev)
9789 and then not Aliased_Present (N)
9791 Error_Msg_Sloc := Sloc (Prev);
9792 Error_Msg_N ("ALIASED required (see declaration#)", N);
9795 -- Check that placement is in private part and that the incomplete
9796 -- declaration appeared in the visible part.
9798 if Ekind (Current_Scope) = E_Package
9799 and then not In_Private_Part (Current_Scope)
9801 Error_Msg_Sloc := Sloc (Prev);
9802 Error_Msg_N ("full constant for declaration#"
9803 & " must be in private part", N);
9805 elsif Ekind (Current_Scope) = E_Package
9806 and then List_Containing (Parent (Prev))
9807 /= Visible_Declarations
9808 (Specification (Unit_Declaration_Node (Current_Scope)))
9811 ("deferred constant must be declared in visible part",
9815 if Is_Access_Type (T)
9816 and then Nkind (Expression (N)) = N_Allocator
9818 Check_Recursive_Declaration (Designated_Type (T));
9821 end Constant_Redeclaration;
9823 ----------------------
9824 -- Constrain_Access --
9825 ----------------------
9827 procedure Constrain_Access
9828 (Def_Id : in out Entity_Id;
9830 Related_Nod : Node_Id)
9832 T : constant Entity_Id := Entity (Subtype_Mark (S));
9833 Desig_Type : constant Entity_Id := Designated_Type (T);
9834 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
9835 Constraint_OK : Boolean := True;
9837 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean;
9838 -- Simple predicate to test for defaulted discriminants
9839 -- Shouldn't this be in sem_util???
9841 ---------------------------------
9842 -- Has_Defaulted_Discriminants --
9843 ---------------------------------
9845 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean is
9847 return Has_Discriminants (Typ)
9848 and then Present (First_Discriminant (Typ))
9850 (Discriminant_Default_Value (First_Discriminant (Typ)));
9851 end Has_Defaulted_Discriminants;
9853 -- Start of processing for Constrain_Access
9856 if Is_Array_Type (Desig_Type) then
9857 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
9859 elsif (Is_Record_Type (Desig_Type)
9860 or else Is_Incomplete_Or_Private_Type (Desig_Type))
9861 and then not Is_Constrained (Desig_Type)
9863 -- ??? The following code is a temporary kludge to ignore a
9864 -- discriminant constraint on access type if it is constraining
9865 -- the current record. Avoid creating the implicit subtype of the
9866 -- record we are currently compiling since right now, we cannot
9867 -- handle these. For now, just return the access type itself.
9869 if Desig_Type = Current_Scope
9870 and then No (Def_Id)
9872 Set_Ekind (Desig_Subtype, E_Record_Subtype);
9873 Def_Id := Entity (Subtype_Mark (S));
9875 -- This call added to ensure that the constraint is analyzed
9876 -- (needed for a B test). Note that we still return early from
9877 -- this procedure to avoid recursive processing. ???
9879 Constrain_Discriminated_Type
9880 (Desig_Subtype, S, Related_Nod, For_Access => True);
9884 if (Ekind (T) = E_General_Access_Type
9885 or else Ada_Version >= Ada_05)
9886 and then Has_Private_Declaration (Desig_Type)
9887 and then In_Open_Scopes (Scope (Desig_Type))
9888 and then Has_Discriminants (Desig_Type)
9890 -- Enforce rule that the constraint is illegal if there is
9891 -- an unconstrained view of the designated type. This means
9892 -- that the partial view (either a private type declaration or
9893 -- a derivation from a private type) has no discriminants.
9894 -- (Defect Report 8652/0008, Technical Corrigendum 1, checked
9895 -- by ACATS B371001).
9897 -- Rule updated for Ada 2005: the private type is said to have
9898 -- a constrained partial view, given that objects of the type
9899 -- can be declared. Furthermore, the rule applies to all access
9900 -- types, unlike the rule concerning default discriminants.
9903 Pack : constant Node_Id :=
9904 Unit_Declaration_Node (Scope (Desig_Type));
9909 if Nkind (Pack) = N_Package_Declaration then
9910 Decls := Visible_Declarations (Specification (Pack));
9911 Decl := First (Decls);
9912 while Present (Decl) loop
9913 if (Nkind (Decl) = N_Private_Type_Declaration
9915 Chars (Defining_Identifier (Decl)) =
9919 (Nkind (Decl) = N_Full_Type_Declaration
9921 Chars (Defining_Identifier (Decl)) =
9923 and then Is_Derived_Type (Desig_Type)
9925 Has_Private_Declaration (Etype (Desig_Type)))
9927 if No (Discriminant_Specifications (Decl)) then
9929 ("cannot constrain general access type if " &
9930 "designated type has constrained partial view",
9943 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
9944 For_Access => True);
9946 elsif (Is_Task_Type (Desig_Type)
9947 or else Is_Protected_Type (Desig_Type))
9948 and then not Is_Constrained (Desig_Type)
9950 Constrain_Concurrent
9951 (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
9954 Error_Msg_N ("invalid constraint on access type", S);
9955 Desig_Subtype := Desig_Type; -- Ignore invalid constraint.
9956 Constraint_OK := False;
9960 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
9962 Set_Ekind (Def_Id, E_Access_Subtype);
9965 if Constraint_OK then
9966 Set_Etype (Def_Id, Base_Type (T));
9968 if Is_Private_Type (Desig_Type) then
9969 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
9972 Set_Etype (Def_Id, Any_Type);
9975 Set_Size_Info (Def_Id, T);
9976 Set_Is_Constrained (Def_Id, Constraint_OK);
9977 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
9978 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
9979 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
9981 Conditional_Delay (Def_Id, T);
9983 -- AI-363 : Subtypes of general access types whose designated types have
9984 -- default discriminants are disallowed. In instances, the rule has to
9985 -- be checked against the actual, of which T is the subtype. In a
9986 -- generic body, the rule is checked assuming that the actual type has
9987 -- defaulted discriminants.
9989 if Ada_Version >= Ada_05 or else Warn_On_Ada_2005_Compatibility then
9990 if Ekind (Base_Type (T)) = E_General_Access_Type
9991 and then Has_Defaulted_Discriminants (Desig_Type)
9993 if Ada_Version < Ada_05 then
9995 ("access subtype of general access type would not " &
9996 "be allowed in Ada 2005?", S);
9999 ("access subype of general access type not allowed", S);
10002 Error_Msg_N ("\discriminants have defaults", S);
10004 elsif Is_Access_Type (T)
10005 and then Is_Generic_Type (Desig_Type)
10006 and then Has_Discriminants (Desig_Type)
10007 and then In_Package_Body (Current_Scope)
10009 if Ada_Version < Ada_05 then
10011 ("access subtype would not be allowed in generic body " &
10012 "in Ada 2005?", S);
10015 ("access subtype not allowed in generic body", S);
10019 ("\designated type is a discriminated formal", S);
10022 end Constrain_Access;
10024 ---------------------
10025 -- Constrain_Array --
10026 ---------------------
10028 procedure Constrain_Array
10029 (Def_Id : in out Entity_Id;
10031 Related_Nod : Node_Id;
10032 Related_Id : Entity_Id;
10033 Suffix : Character)
10035 C : constant Node_Id := Constraint (SI);
10036 Number_Of_Constraints : Nat := 0;
10039 Constraint_OK : Boolean := True;
10042 T := Entity (Subtype_Mark (SI));
10044 if Ekind (T) in Access_Kind then
10045 T := Designated_Type (T);
10048 -- If an index constraint follows a subtype mark in a subtype indication
10049 -- then the type or subtype denoted by the subtype mark must not already
10050 -- impose an index constraint. The subtype mark must denote either an
10051 -- unconstrained array type or an access type whose designated type
10052 -- is such an array type... (RM 3.6.1)
10054 if Is_Constrained (T) then
10056 ("array type is already constrained", Subtype_Mark (SI));
10057 Constraint_OK := False;
10060 S := First (Constraints (C));
10061 while Present (S) loop
10062 Number_Of_Constraints := Number_Of_Constraints + 1;
10066 -- In either case, the index constraint must provide a discrete
10067 -- range for each index of the array type and the type of each
10068 -- discrete range must be the same as that of the corresponding
10069 -- index. (RM 3.6.1)
10071 if Number_Of_Constraints /= Number_Dimensions (T) then
10072 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
10073 Constraint_OK := False;
10076 S := First (Constraints (C));
10077 Index := First_Index (T);
10080 -- Apply constraints to each index type
10082 for J in 1 .. Number_Of_Constraints loop
10083 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
10091 if No (Def_Id) then
10093 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
10094 Set_Parent (Def_Id, Related_Nod);
10097 Set_Ekind (Def_Id, E_Array_Subtype);
10100 Set_Size_Info (Def_Id, (T));
10101 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10102 Set_Etype (Def_Id, Base_Type (T));
10104 if Constraint_OK then
10105 Set_First_Index (Def_Id, First (Constraints (C)));
10107 Set_First_Index (Def_Id, First_Index (T));
10110 Set_Is_Constrained (Def_Id, True);
10111 Set_Is_Aliased (Def_Id, Is_Aliased (T));
10112 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10114 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
10115 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
10117 -- A subtype does not inherit the packed_array_type of is parent. We
10118 -- need to initialize the attribute because if Def_Id is previously
10119 -- analyzed through a limited_with clause, it will have the attributes
10120 -- of an incomplete type, one of which is an Elist that overlaps the
10121 -- Packed_Array_Type field.
10123 Set_Packed_Array_Type (Def_Id, Empty);
10125 -- Build a freeze node if parent still needs one. Also make sure that
10126 -- the Depends_On_Private status is set because the subtype will need
10127 -- reprocessing at the time the base type does, and also we must set a
10128 -- conditional delay.
10130 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
10131 Conditional_Delay (Def_Id, T);
10132 end Constrain_Array;
10134 ------------------------------
10135 -- Constrain_Component_Type --
10136 ------------------------------
10138 function Constrain_Component_Type
10140 Constrained_Typ : Entity_Id;
10141 Related_Node : Node_Id;
10143 Constraints : Elist_Id) return Entity_Id
10145 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
10146 Compon_Type : constant Entity_Id := Etype (Comp);
10148 function Build_Constrained_Array_Type
10149 (Old_Type : Entity_Id) return Entity_Id;
10150 -- If Old_Type is an array type, one of whose indices is constrained
10151 -- by a discriminant, build an Itype whose constraint replaces the
10152 -- discriminant with its value in the constraint.
10154 function Build_Constrained_Discriminated_Type
10155 (Old_Type : Entity_Id) return Entity_Id;
10156 -- Ditto for record components
10158 function Build_Constrained_Access_Type
10159 (Old_Type : Entity_Id) return Entity_Id;
10160 -- Ditto for access types. Makes use of previous two functions, to
10161 -- constrain designated type.
10163 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
10164 -- T is an array or discriminated type, C is a list of constraints
10165 -- that apply to T. This routine builds the constrained subtype.
10167 function Is_Discriminant (Expr : Node_Id) return Boolean;
10168 -- Returns True if Expr is a discriminant
10170 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
10171 -- Find the value of discriminant Discrim in Constraint
10173 -----------------------------------
10174 -- Build_Constrained_Access_Type --
10175 -----------------------------------
10177 function Build_Constrained_Access_Type
10178 (Old_Type : Entity_Id) return Entity_Id
10180 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
10182 Desig_Subtype : Entity_Id;
10186 -- if the original access type was not embedded in the enclosing
10187 -- type definition, there is no need to produce a new access
10188 -- subtype. In fact every access type with an explicit constraint
10189 -- generates an itype whose scope is the enclosing record.
10191 if not Is_Type (Scope (Old_Type)) then
10194 elsif Is_Array_Type (Desig_Type) then
10195 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
10197 elsif Has_Discriminants (Desig_Type) then
10199 -- This may be an access type to an enclosing record type for
10200 -- which we are constructing the constrained components. Return
10201 -- the enclosing record subtype. This is not always correct,
10202 -- but avoids infinite recursion. ???
10204 Desig_Subtype := Any_Type;
10206 for J in reverse 0 .. Scope_Stack.Last loop
10207 Scop := Scope_Stack.Table (J).Entity;
10210 and then Base_Type (Scop) = Base_Type (Desig_Type)
10212 Desig_Subtype := Scop;
10215 exit when not Is_Type (Scop);
10218 if Desig_Subtype = Any_Type then
10220 Build_Constrained_Discriminated_Type (Desig_Type);
10227 if Desig_Subtype /= Desig_Type then
10229 -- The Related_Node better be here or else we won't be able
10230 -- to attach new itypes to a node in the tree.
10232 pragma Assert (Present (Related_Node));
10234 Itype := Create_Itype (E_Access_Subtype, Related_Node);
10236 Set_Etype (Itype, Base_Type (Old_Type));
10237 Set_Size_Info (Itype, (Old_Type));
10238 Set_Directly_Designated_Type (Itype, Desig_Subtype);
10239 Set_Depends_On_Private (Itype, Has_Private_Component
10241 Set_Is_Access_Constant (Itype, Is_Access_Constant
10244 -- The new itype needs freezing when it depends on a not frozen
10245 -- type and the enclosing subtype needs freezing.
10247 if Has_Delayed_Freeze (Constrained_Typ)
10248 and then not Is_Frozen (Constrained_Typ)
10250 Conditional_Delay (Itype, Base_Type (Old_Type));
10258 end Build_Constrained_Access_Type;
10260 ----------------------------------
10261 -- Build_Constrained_Array_Type --
10262 ----------------------------------
10264 function Build_Constrained_Array_Type
10265 (Old_Type : Entity_Id) return Entity_Id
10269 Old_Index : Node_Id;
10270 Range_Node : Node_Id;
10271 Constr_List : List_Id;
10273 Need_To_Create_Itype : Boolean := False;
10276 Old_Index := First_Index (Old_Type);
10277 while Present (Old_Index) loop
10278 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
10280 if Is_Discriminant (Lo_Expr)
10281 or else Is_Discriminant (Hi_Expr)
10283 Need_To_Create_Itype := True;
10286 Next_Index (Old_Index);
10289 if Need_To_Create_Itype then
10290 Constr_List := New_List;
10292 Old_Index := First_Index (Old_Type);
10293 while Present (Old_Index) loop
10294 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
10296 if Is_Discriminant (Lo_Expr) then
10297 Lo_Expr := Get_Discr_Value (Lo_Expr);
10300 if Is_Discriminant (Hi_Expr) then
10301 Hi_Expr := Get_Discr_Value (Hi_Expr);
10306 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
10308 Append (Range_Node, To => Constr_List);
10310 Next_Index (Old_Index);
10313 return Build_Subtype (Old_Type, Constr_List);
10318 end Build_Constrained_Array_Type;
10320 ------------------------------------------
10321 -- Build_Constrained_Discriminated_Type --
10322 ------------------------------------------
10324 function Build_Constrained_Discriminated_Type
10325 (Old_Type : Entity_Id) return Entity_Id
10328 Constr_List : List_Id;
10329 Old_Constraint : Elmt_Id;
10331 Need_To_Create_Itype : Boolean := False;
10334 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
10335 while Present (Old_Constraint) loop
10336 Expr := Node (Old_Constraint);
10338 if Is_Discriminant (Expr) then
10339 Need_To_Create_Itype := True;
10342 Next_Elmt (Old_Constraint);
10345 if Need_To_Create_Itype then
10346 Constr_List := New_List;
10348 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
10349 while Present (Old_Constraint) loop
10350 Expr := Node (Old_Constraint);
10352 if Is_Discriminant (Expr) then
10353 Expr := Get_Discr_Value (Expr);
10356 Append (New_Copy_Tree (Expr), To => Constr_List);
10358 Next_Elmt (Old_Constraint);
10361 return Build_Subtype (Old_Type, Constr_List);
10366 end Build_Constrained_Discriminated_Type;
10368 -------------------
10369 -- Build_Subtype --
10370 -------------------
10372 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
10374 Subtyp_Decl : Node_Id;
10375 Def_Id : Entity_Id;
10376 Btyp : Entity_Id := Base_Type (T);
10379 -- The Related_Node better be here or else we won't be able to
10380 -- attach new itypes to a node in the tree.
10382 pragma Assert (Present (Related_Node));
10384 -- If the view of the component's type is incomplete or private
10385 -- with unknown discriminants, then the constraint must be applied
10386 -- to the full type.
10388 if Has_Unknown_Discriminants (Btyp)
10389 and then Present (Underlying_Type (Btyp))
10391 Btyp := Underlying_Type (Btyp);
10395 Make_Subtype_Indication (Loc,
10396 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
10397 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
10399 Def_Id := Create_Itype (Ekind (T), Related_Node);
10402 Make_Subtype_Declaration (Loc,
10403 Defining_Identifier => Def_Id,
10404 Subtype_Indication => Indic);
10406 Set_Parent (Subtyp_Decl, Parent (Related_Node));
10408 -- Itypes must be analyzed with checks off (see package Itypes)
10410 Analyze (Subtyp_Decl, Suppress => All_Checks);
10415 ---------------------
10416 -- Get_Discr_Value --
10417 ---------------------
10419 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
10424 -- The discriminant may be declared for the type, in which case we
10425 -- find it by iterating over the list of discriminants. If the
10426 -- discriminant is inherited from a parent type, it appears as the
10427 -- corresponding discriminant of the current type. This will be the
10428 -- case when constraining an inherited component whose constraint is
10429 -- given by a discriminant of the parent.
10431 D := First_Discriminant (Typ);
10432 E := First_Elmt (Constraints);
10434 while Present (D) loop
10435 if D = Entity (Discrim)
10436 or else D = CR_Discriminant (Entity (Discrim))
10437 or else Corresponding_Discriminant (D) = Entity (Discrim)
10442 Next_Discriminant (D);
10446 -- The corresponding_Discriminant mechanism is incomplete, because
10447 -- the correspondence between new and old discriminants is not one
10448 -- to one: one new discriminant can constrain several old ones. In
10449 -- that case, scan sequentially the stored_constraint, the list of
10450 -- discriminants of the parents, and the constraints.
10451 -- Previous code checked for the present of the Stored_Constraint
10452 -- list for the derived type, but did not use it at all. Should it
10453 -- be present when the component is a discriminated task type?
10455 if Is_Derived_Type (Typ)
10456 and then Scope (Entity (Discrim)) = Etype (Typ)
10458 D := First_Discriminant (Etype (Typ));
10459 E := First_Elmt (Constraints);
10460 while Present (D) loop
10461 if D = Entity (Discrim) then
10465 Next_Discriminant (D);
10470 -- Something is wrong if we did not find the value
10472 raise Program_Error;
10473 end Get_Discr_Value;
10475 ---------------------
10476 -- Is_Discriminant --
10477 ---------------------
10479 function Is_Discriminant (Expr : Node_Id) return Boolean is
10480 Discrim_Scope : Entity_Id;
10483 if Denotes_Discriminant (Expr) then
10484 Discrim_Scope := Scope (Entity (Expr));
10486 -- Either we have a reference to one of Typ's discriminants,
10488 pragma Assert (Discrim_Scope = Typ
10490 -- or to the discriminants of the parent type, in the case
10491 -- of a derivation of a tagged type with variants.
10493 or else Discrim_Scope = Etype (Typ)
10494 or else Full_View (Discrim_Scope) = Etype (Typ)
10496 -- or same as above for the case where the discriminants
10497 -- were declared in Typ's private view.
10499 or else (Is_Private_Type (Discrim_Scope)
10500 and then Chars (Discrim_Scope) = Chars (Typ))
10502 -- or else we are deriving from the full view and the
10503 -- discriminant is declared in the private entity.
10505 or else (Is_Private_Type (Typ)
10506 and then Chars (Discrim_Scope) = Chars (Typ))
10508 -- Or we are constrained the corresponding record of a
10509 -- synchronized type that completes a private declaration.
10511 or else (Is_Concurrent_Record_Type (Typ)
10513 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
10515 -- or we have a class-wide type, in which case make sure the
10516 -- discriminant found belongs to the root type.
10518 or else (Is_Class_Wide_Type (Typ)
10519 and then Etype (Typ) = Discrim_Scope));
10524 -- In all other cases we have something wrong
10527 end Is_Discriminant;
10529 -- Start of processing for Constrain_Component_Type
10532 if Nkind (Parent (Comp)) = N_Component_Declaration
10533 and then Comes_From_Source (Parent (Comp))
10534 and then Comes_From_Source
10535 (Subtype_Indication (Component_Definition (Parent (Comp))))
10538 (Subtype_Indication (Component_Definition (Parent (Comp))))
10540 return Compon_Type;
10542 elsif Is_Array_Type (Compon_Type) then
10543 return Build_Constrained_Array_Type (Compon_Type);
10545 elsif Has_Discriminants (Compon_Type) then
10546 return Build_Constrained_Discriminated_Type (Compon_Type);
10548 elsif Is_Access_Type (Compon_Type) then
10549 return Build_Constrained_Access_Type (Compon_Type);
10552 return Compon_Type;
10554 end Constrain_Component_Type;
10556 --------------------------
10557 -- Constrain_Concurrent --
10558 --------------------------
10560 -- For concurrent types, the associated record value type carries the same
10561 -- discriminants, so when we constrain a concurrent type, we must constrain
10562 -- the corresponding record type as well.
10564 procedure Constrain_Concurrent
10565 (Def_Id : in out Entity_Id;
10567 Related_Nod : Node_Id;
10568 Related_Id : Entity_Id;
10569 Suffix : Character)
10571 T_Ent : Entity_Id := Entity (Subtype_Mark (SI));
10575 if Ekind (T_Ent) in Access_Kind then
10576 T_Ent := Designated_Type (T_Ent);
10579 T_Val := Corresponding_Record_Type (T_Ent);
10581 if Present (T_Val) then
10583 if No (Def_Id) then
10584 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
10587 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
10589 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10590 Set_Corresponding_Record_Type (Def_Id,
10591 Constrain_Corresponding_Record
10592 (Def_Id, T_Val, Related_Nod, Related_Id));
10595 -- If there is no associated record, expansion is disabled and this
10596 -- is a generic context. Create a subtype in any case, so that
10597 -- semantic analysis can proceed.
10599 if No (Def_Id) then
10600 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
10603 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
10605 end Constrain_Concurrent;
10607 ------------------------------------
10608 -- Constrain_Corresponding_Record --
10609 ------------------------------------
10611 function Constrain_Corresponding_Record
10612 (Prot_Subt : Entity_Id;
10613 Corr_Rec : Entity_Id;
10614 Related_Nod : Node_Id;
10615 Related_Id : Entity_Id) return Entity_Id
10617 T_Sub : constant Entity_Id :=
10618 Create_Itype (E_Record_Subtype, Related_Nod, Related_Id, 'V');
10621 Set_Etype (T_Sub, Corr_Rec);
10622 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
10623 Set_Is_Constrained (T_Sub, True);
10624 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
10625 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
10627 -- As elsewhere, we do not want to create a freeze node for this itype
10628 -- if it is created for a constrained component of an enclosing record
10629 -- because references to outer discriminants will appear out of scope.
10631 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
10632 Conditional_Delay (T_Sub, Corr_Rec);
10634 Set_Is_Frozen (T_Sub);
10637 if Has_Discriminants (Prot_Subt) then -- False only if errors.
10638 Set_Discriminant_Constraint
10639 (T_Sub, Discriminant_Constraint (Prot_Subt));
10640 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
10641 Create_Constrained_Components
10642 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
10645 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
10648 end Constrain_Corresponding_Record;
10650 -----------------------
10651 -- Constrain_Decimal --
10652 -----------------------
10654 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
10655 T : constant Entity_Id := Entity (Subtype_Mark (S));
10656 C : constant Node_Id := Constraint (S);
10657 Loc : constant Source_Ptr := Sloc (C);
10658 Range_Expr : Node_Id;
10659 Digits_Expr : Node_Id;
10664 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
10666 if Nkind (C) = N_Range_Constraint then
10667 Range_Expr := Range_Expression (C);
10668 Digits_Val := Digits_Value (T);
10671 pragma Assert (Nkind (C) = N_Digits_Constraint);
10672 Digits_Expr := Digits_Expression (C);
10673 Analyze_And_Resolve (Digits_Expr, Any_Integer);
10675 Check_Digits_Expression (Digits_Expr);
10676 Digits_Val := Expr_Value (Digits_Expr);
10678 if Digits_Val > Digits_Value (T) then
10680 ("digits expression is incompatible with subtype", C);
10681 Digits_Val := Digits_Value (T);
10684 if Present (Range_Constraint (C)) then
10685 Range_Expr := Range_Expression (Range_Constraint (C));
10687 Range_Expr := Empty;
10691 Set_Etype (Def_Id, Base_Type (T));
10692 Set_Size_Info (Def_Id, (T));
10693 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10694 Set_Delta_Value (Def_Id, Delta_Value (T));
10695 Set_Scale_Value (Def_Id, Scale_Value (T));
10696 Set_Small_Value (Def_Id, Small_Value (T));
10697 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
10698 Set_Digits_Value (Def_Id, Digits_Val);
10700 -- Manufacture range from given digits value if no range present
10702 if No (Range_Expr) then
10703 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
10707 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
10709 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
10712 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
10713 Set_Discrete_RM_Size (Def_Id);
10715 -- Unconditionally delay the freeze, since we cannot set size
10716 -- information in all cases correctly until the freeze point.
10718 Set_Has_Delayed_Freeze (Def_Id);
10719 end Constrain_Decimal;
10721 ----------------------------------
10722 -- Constrain_Discriminated_Type --
10723 ----------------------------------
10725 procedure Constrain_Discriminated_Type
10726 (Def_Id : Entity_Id;
10728 Related_Nod : Node_Id;
10729 For_Access : Boolean := False)
10731 E : constant Entity_Id := Entity (Subtype_Mark (S));
10734 Elist : Elist_Id := New_Elmt_List;
10736 procedure Fixup_Bad_Constraint;
10737 -- This is called after finding a bad constraint, and after having
10738 -- posted an appropriate error message. The mission is to leave the
10739 -- entity T in as reasonable state as possible!
10741 --------------------------
10742 -- Fixup_Bad_Constraint --
10743 --------------------------
10745 procedure Fixup_Bad_Constraint is
10747 -- Set a reasonable Ekind for the entity. For an incomplete type,
10748 -- we can't do much, but for other types, we can set the proper
10749 -- corresponding subtype kind.
10751 if Ekind (T) = E_Incomplete_Type then
10752 Set_Ekind (Def_Id, Ekind (T));
10754 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
10757 -- Set Etype to the known type, to reduce chances of cascaded errors
10759 Set_Etype (Def_Id, E);
10760 Set_Error_Posted (Def_Id);
10761 end Fixup_Bad_Constraint;
10763 -- Start of processing for Constrain_Discriminated_Type
10766 C := Constraint (S);
10768 -- A discriminant constraint is only allowed in a subtype indication,
10769 -- after a subtype mark. This subtype mark must denote either a type
10770 -- with discriminants, or an access type whose designated type is a
10771 -- type with discriminants. A discriminant constraint specifies the
10772 -- values of these discriminants (RM 3.7.2(5)).
10774 T := Base_Type (Entity (Subtype_Mark (S)));
10776 if Ekind (T) in Access_Kind then
10777 T := Designated_Type (T);
10780 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
10781 -- Avoid generating an error for access-to-incomplete subtypes.
10783 if Ada_Version >= Ada_05
10784 and then Ekind (T) = E_Incomplete_Type
10785 and then Nkind (Parent (S)) = N_Subtype_Declaration
10786 and then not Is_Itype (Def_Id)
10788 -- A little sanity check, emit an error message if the type
10789 -- has discriminants to begin with. Type T may be a regular
10790 -- incomplete type or imported via a limited with clause.
10792 if Has_Discriminants (T)
10794 (From_With_Type (T)
10795 and then Present (Non_Limited_View (T))
10796 and then Nkind (Parent (Non_Limited_View (T))) =
10797 N_Full_Type_Declaration
10798 and then Present (Discriminant_Specifications
10799 (Parent (Non_Limited_View (T)))))
10802 ("(Ada 2005) incomplete subtype may not be constrained", C);
10805 ("invalid constraint: type has no discriminant", C);
10808 Fixup_Bad_Constraint;
10811 -- Check that the type has visible discriminants. The type may be
10812 -- a private type with unknown discriminants whose full view has
10813 -- discriminants which are invisible.
10815 elsif not Has_Discriminants (T)
10817 (Has_Unknown_Discriminants (T)
10818 and then Is_Private_Type (T))
10820 Error_Msg_N ("invalid constraint: type has no discriminant", C);
10821 Fixup_Bad_Constraint;
10824 elsif Is_Constrained (E)
10825 or else (Ekind (E) = E_Class_Wide_Subtype
10826 and then Present (Discriminant_Constraint (E)))
10828 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
10829 Fixup_Bad_Constraint;
10833 -- T may be an unconstrained subtype (e.g. a generic actual).
10834 -- Constraint applies to the base type.
10836 T := Base_Type (T);
10838 Elist := Build_Discriminant_Constraints (T, S);
10840 -- If the list returned was empty we had an error in building the
10841 -- discriminant constraint. We have also already signalled an error
10842 -- in the incomplete type case
10844 if Is_Empty_Elmt_List (Elist) then
10845 Fixup_Bad_Constraint;
10849 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
10850 end Constrain_Discriminated_Type;
10852 ---------------------------
10853 -- Constrain_Enumeration --
10854 ---------------------------
10856 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
10857 T : constant Entity_Id := Entity (Subtype_Mark (S));
10858 C : constant Node_Id := Constraint (S);
10861 Set_Ekind (Def_Id, E_Enumeration_Subtype);
10863 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
10865 Set_Etype (Def_Id, Base_Type (T));
10866 Set_Size_Info (Def_Id, (T));
10867 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10868 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
10870 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
10872 Set_Discrete_RM_Size (Def_Id);
10873 end Constrain_Enumeration;
10875 ----------------------
10876 -- Constrain_Float --
10877 ----------------------
10879 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
10880 T : constant Entity_Id := Entity (Subtype_Mark (S));
10886 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
10888 Set_Etype (Def_Id, Base_Type (T));
10889 Set_Size_Info (Def_Id, (T));
10890 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10892 -- Process the constraint
10894 C := Constraint (S);
10896 -- Digits constraint present
10898 if Nkind (C) = N_Digits_Constraint then
10899 Check_Restriction (No_Obsolescent_Features, C);
10901 if Warn_On_Obsolescent_Feature then
10903 ("subtype digits constraint is an " &
10904 "obsolescent feature (RM J.3(8))?", C);
10907 D := Digits_Expression (C);
10908 Analyze_And_Resolve (D, Any_Integer);
10909 Check_Digits_Expression (D);
10910 Set_Digits_Value (Def_Id, Expr_Value (D));
10912 -- Check that digits value is in range. Obviously we can do this
10913 -- at compile time, but it is strictly a runtime check, and of
10914 -- course there is an ACVC test that checks this!
10916 if Digits_Value (Def_Id) > Digits_Value (T) then
10917 Error_Msg_Uint_1 := Digits_Value (T);
10918 Error_Msg_N ("?digits value is too large, maximum is ^", D);
10920 Make_Raise_Constraint_Error (Sloc (D),
10921 Reason => CE_Range_Check_Failed);
10922 Insert_Action (Declaration_Node (Def_Id), Rais);
10925 C := Range_Constraint (C);
10927 -- No digits constraint present
10930 Set_Digits_Value (Def_Id, Digits_Value (T));
10933 -- Range constraint present
10935 if Nkind (C) = N_Range_Constraint then
10936 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
10938 -- No range constraint present
10941 pragma Assert (No (C));
10942 Set_Scalar_Range (Def_Id, Scalar_Range (T));
10945 Set_Is_Constrained (Def_Id);
10946 end Constrain_Float;
10948 ---------------------
10949 -- Constrain_Index --
10950 ---------------------
10952 procedure Constrain_Index
10955 Related_Nod : Node_Id;
10956 Related_Id : Entity_Id;
10957 Suffix : Character;
10958 Suffix_Index : Nat)
10960 Def_Id : Entity_Id;
10961 R : Node_Id := Empty;
10962 T : constant Entity_Id := Etype (Index);
10965 if Nkind (S) = N_Range
10967 (Nkind (S) = N_Attribute_Reference
10968 and then Attribute_Name (S) = Name_Range)
10970 -- A Range attribute will transformed into N_Range by Resolve
10976 Process_Range_Expr_In_Decl (R, T, Empty_List);
10978 if not Error_Posted (S)
10980 (Nkind (S) /= N_Range
10981 or else not Covers (T, (Etype (Low_Bound (S))))
10982 or else not Covers (T, (Etype (High_Bound (S)))))
10984 if Base_Type (T) /= Any_Type
10985 and then Etype (Low_Bound (S)) /= Any_Type
10986 and then Etype (High_Bound (S)) /= Any_Type
10988 Error_Msg_N ("range expected", S);
10992 elsif Nkind (S) = N_Subtype_Indication then
10994 -- The parser has verified that this is a discrete indication
10996 Resolve_Discrete_Subtype_Indication (S, T);
10997 R := Range_Expression (Constraint (S));
10999 elsif Nkind (S) = N_Discriminant_Association then
11001 -- Syntactically valid in subtype indication
11003 Error_Msg_N ("invalid index constraint", S);
11004 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11007 -- Subtype_Mark case, no anonymous subtypes to construct
11012 if Is_Entity_Name (S) then
11013 if not Is_Type (Entity (S)) then
11014 Error_Msg_N ("expect subtype mark for index constraint", S);
11016 elsif Base_Type (Entity (S)) /= Base_Type (T) then
11017 Wrong_Type (S, Base_Type (T));
11023 Error_Msg_N ("invalid index constraint", S);
11024 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11030 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
11032 Set_Etype (Def_Id, Base_Type (T));
11034 if Is_Modular_Integer_Type (T) then
11035 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11037 elsif Is_Integer_Type (T) then
11038 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11041 Set_Ekind (Def_Id, E_Enumeration_Subtype);
11042 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
11045 Set_Size_Info (Def_Id, (T));
11046 Set_RM_Size (Def_Id, RM_Size (T));
11047 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11049 Set_Scalar_Range (Def_Id, R);
11051 Set_Etype (S, Def_Id);
11052 Set_Discrete_RM_Size (Def_Id);
11053 end Constrain_Index;
11055 -----------------------
11056 -- Constrain_Integer --
11057 -----------------------
11059 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
11060 T : constant Entity_Id := Entity (Subtype_Mark (S));
11061 C : constant Node_Id := Constraint (S);
11064 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11066 if Is_Modular_Integer_Type (T) then
11067 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11069 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11072 Set_Etype (Def_Id, Base_Type (T));
11073 Set_Size_Info (Def_Id, (T));
11074 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11075 Set_Discrete_RM_Size (Def_Id);
11076 end Constrain_Integer;
11078 ------------------------------
11079 -- Constrain_Ordinary_Fixed --
11080 ------------------------------
11082 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
11083 T : constant Entity_Id := Entity (Subtype_Mark (S));
11089 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
11090 Set_Etype (Def_Id, Base_Type (T));
11091 Set_Size_Info (Def_Id, (T));
11092 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11093 Set_Small_Value (Def_Id, Small_Value (T));
11095 -- Process the constraint
11097 C := Constraint (S);
11099 -- Delta constraint present
11101 if Nkind (C) = N_Delta_Constraint then
11102 Check_Restriction (No_Obsolescent_Features, C);
11104 if Warn_On_Obsolescent_Feature then
11106 ("subtype delta constraint is an " &
11107 "obsolescent feature (RM J.3(7))?");
11110 D := Delta_Expression (C);
11111 Analyze_And_Resolve (D, Any_Real);
11112 Check_Delta_Expression (D);
11113 Set_Delta_Value (Def_Id, Expr_Value_R (D));
11115 -- Check that delta value is in range. Obviously we can do this
11116 -- at compile time, but it is strictly a runtime check, and of
11117 -- course there is an ACVC test that checks this!
11119 if Delta_Value (Def_Id) < Delta_Value (T) then
11120 Error_Msg_N ("?delta value is too small", D);
11122 Make_Raise_Constraint_Error (Sloc (D),
11123 Reason => CE_Range_Check_Failed);
11124 Insert_Action (Declaration_Node (Def_Id), Rais);
11127 C := Range_Constraint (C);
11129 -- No delta constraint present
11132 Set_Delta_Value (Def_Id, Delta_Value (T));
11135 -- Range constraint present
11137 if Nkind (C) = N_Range_Constraint then
11138 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11140 -- No range constraint present
11143 pragma Assert (No (C));
11144 Set_Scalar_Range (Def_Id, Scalar_Range (T));
11148 Set_Discrete_RM_Size (Def_Id);
11150 -- Unconditionally delay the freeze, since we cannot set size
11151 -- information in all cases correctly until the freeze point.
11153 Set_Has_Delayed_Freeze (Def_Id);
11154 end Constrain_Ordinary_Fixed;
11156 -----------------------
11157 -- Contain_Interface --
11158 -----------------------
11160 function Contain_Interface
11161 (Iface : Entity_Id;
11162 Ifaces : Elist_Id) return Boolean
11164 Iface_Elmt : Elmt_Id;
11167 if Present (Ifaces) then
11168 Iface_Elmt := First_Elmt (Ifaces);
11169 while Present (Iface_Elmt) loop
11170 if Node (Iface_Elmt) = Iface then
11174 Next_Elmt (Iface_Elmt);
11179 end Contain_Interface;
11181 ---------------------------
11182 -- Convert_Scalar_Bounds --
11183 ---------------------------
11185 procedure Convert_Scalar_Bounds
11187 Parent_Type : Entity_Id;
11188 Derived_Type : Entity_Id;
11191 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
11198 Lo := Build_Scalar_Bound
11199 (Type_Low_Bound (Derived_Type),
11200 Parent_Type, Implicit_Base);
11202 Hi := Build_Scalar_Bound
11203 (Type_High_Bound (Derived_Type),
11204 Parent_Type, Implicit_Base);
11211 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
11213 Set_Parent (Rng, N);
11214 Set_Scalar_Range (Derived_Type, Rng);
11216 -- Analyze the bounds
11218 Analyze_And_Resolve (Lo, Implicit_Base);
11219 Analyze_And_Resolve (Hi, Implicit_Base);
11221 -- Analyze the range itself, except that we do not analyze it if
11222 -- the bounds are real literals, and we have a fixed-point type.
11223 -- The reason for this is that we delay setting the bounds in this
11224 -- case till we know the final Small and Size values (see circuit
11225 -- in Freeze.Freeze_Fixed_Point_Type for further details).
11227 if Is_Fixed_Point_Type (Parent_Type)
11228 and then Nkind (Lo) = N_Real_Literal
11229 and then Nkind (Hi) = N_Real_Literal
11233 -- Here we do the analysis of the range
11235 -- Note: we do this manually, since if we do a normal Analyze and
11236 -- Resolve call, there are problems with the conversions used for
11237 -- the derived type range.
11240 Set_Etype (Rng, Implicit_Base);
11241 Set_Analyzed (Rng, True);
11243 end Convert_Scalar_Bounds;
11245 -------------------
11246 -- Copy_And_Swap --
11247 -------------------
11249 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
11251 -- Initialize new full declaration entity by copying the pertinent
11252 -- fields of the corresponding private declaration entity.
11254 -- We temporarily set Ekind to a value appropriate for a type to
11255 -- avoid assert failures in Einfo from checking for setting type
11256 -- attributes on something that is not a type. Ekind (Priv) is an
11257 -- appropriate choice, since it allowed the attributes to be set
11258 -- in the first place. This Ekind value will be modified later.
11260 Set_Ekind (Full, Ekind (Priv));
11262 -- Also set Etype temporarily to Any_Type, again, in the absence
11263 -- of errors, it will be properly reset, and if there are errors,
11264 -- then we want a value of Any_Type to remain.
11266 Set_Etype (Full, Any_Type);
11268 -- Now start copying attributes
11270 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
11272 if Has_Discriminants (Full) then
11273 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
11274 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
11277 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
11278 Set_Homonym (Full, Homonym (Priv));
11279 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
11280 Set_Is_Public (Full, Is_Public (Priv));
11281 Set_Is_Pure (Full, Is_Pure (Priv));
11282 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
11283 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
11284 Set_Has_Pragma_Unreferenced_Objects
11285 (Full, Has_Pragma_Unreferenced_Objects
11288 Conditional_Delay (Full, Priv);
11290 if Is_Tagged_Type (Full) then
11291 Set_Primitive_Operations (Full, Primitive_Operations (Priv));
11293 if Priv = Base_Type (Priv) then
11294 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
11298 Set_Is_Volatile (Full, Is_Volatile (Priv));
11299 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
11300 Set_Scope (Full, Scope (Priv));
11301 Set_Next_Entity (Full, Next_Entity (Priv));
11302 Set_First_Entity (Full, First_Entity (Priv));
11303 Set_Last_Entity (Full, Last_Entity (Priv));
11305 -- If access types have been recorded for later handling, keep them in
11306 -- the full view so that they get handled when the full view freeze
11307 -- node is expanded.
11309 if Present (Freeze_Node (Priv))
11310 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
11312 Ensure_Freeze_Node (Full);
11313 Set_Access_Types_To_Process
11314 (Freeze_Node (Full),
11315 Access_Types_To_Process (Freeze_Node (Priv)));
11318 -- Swap the two entities. Now Privat is the full type entity and
11319 -- Full is the private one. They will be swapped back at the end
11320 -- of the private part. This swapping ensures that the entity that
11321 -- is visible in the private part is the full declaration.
11323 Exchange_Entities (Priv, Full);
11324 Append_Entity (Full, Scope (Full));
11327 -------------------------------------
11328 -- Copy_Array_Base_Type_Attributes --
11329 -------------------------------------
11331 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
11333 Set_Component_Alignment (T1, Component_Alignment (T2));
11334 Set_Component_Type (T1, Component_Type (T2));
11335 Set_Component_Size (T1, Component_Size (T2));
11336 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
11337 Set_Finalize_Storage_Only (T1, Finalize_Storage_Only (T2));
11338 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
11339 Set_Has_Task (T1, Has_Task (T2));
11340 Set_Is_Packed (T1, Is_Packed (T2));
11341 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
11342 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
11343 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
11344 end Copy_Array_Base_Type_Attributes;
11346 -----------------------------------
11347 -- Copy_Array_Subtype_Attributes --
11348 -----------------------------------
11350 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
11352 Set_Size_Info (T1, T2);
11354 Set_First_Index (T1, First_Index (T2));
11355 Set_Is_Aliased (T1, Is_Aliased (T2));
11356 Set_Is_Atomic (T1, Is_Atomic (T2));
11357 Set_Is_Volatile (T1, Is_Volatile (T2));
11358 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
11359 Set_Is_Constrained (T1, Is_Constrained (T2));
11360 Set_Depends_On_Private (T1, Has_Private_Component (T2));
11361 Set_First_Rep_Item (T1, First_Rep_Item (T2));
11362 Set_Convention (T1, Convention (T2));
11363 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
11364 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
11365 Set_Packed_Array_Type (T1, Packed_Array_Type (T2));
11366 end Copy_Array_Subtype_Attributes;
11368 -----------------------------------
11369 -- Create_Constrained_Components --
11370 -----------------------------------
11372 procedure Create_Constrained_Components
11374 Decl_Node : Node_Id;
11376 Constraints : Elist_Id)
11378 Loc : constant Source_Ptr := Sloc (Subt);
11379 Comp_List : constant Elist_Id := New_Elmt_List;
11380 Parent_Type : constant Entity_Id := Etype (Typ);
11381 Assoc_List : constant List_Id := New_List;
11382 Discr_Val : Elmt_Id;
11386 Is_Static : Boolean := True;
11388 procedure Collect_Fixed_Components (Typ : Entity_Id);
11389 -- Collect parent type components that do not appear in a variant part
11391 procedure Create_All_Components;
11392 -- Iterate over Comp_List to create the components of the subtype
11394 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
11395 -- Creates a new component from Old_Compon, copying all the fields from
11396 -- it, including its Etype, inserts the new component in the Subt entity
11397 -- chain and returns the new component.
11399 function Is_Variant_Record (T : Entity_Id) return Boolean;
11400 -- If true, and discriminants are static, collect only components from
11401 -- variants selected by discriminant values.
11403 ------------------------------
11404 -- Collect_Fixed_Components --
11405 ------------------------------
11407 procedure Collect_Fixed_Components (Typ : Entity_Id) is
11409 -- Build association list for discriminants, and find components of the
11410 -- variant part selected by the values of the discriminants.
11412 Old_C := First_Discriminant (Typ);
11413 Discr_Val := First_Elmt (Constraints);
11414 while Present (Old_C) loop
11415 Append_To (Assoc_List,
11416 Make_Component_Association (Loc,
11417 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
11418 Expression => New_Copy (Node (Discr_Val))));
11420 Next_Elmt (Discr_Val);
11421 Next_Discriminant (Old_C);
11424 -- The tag, and the possible parent and controller components
11425 -- are unconditionally in the subtype.
11427 if Is_Tagged_Type (Typ)
11428 or else Has_Controlled_Component (Typ)
11430 Old_C := First_Component (Typ);
11431 while Present (Old_C) loop
11432 if Chars ((Old_C)) = Name_uTag
11433 or else Chars ((Old_C)) = Name_uParent
11434 or else Chars ((Old_C)) = Name_uController
11436 Append_Elmt (Old_C, Comp_List);
11439 Next_Component (Old_C);
11442 end Collect_Fixed_Components;
11444 ---------------------------
11445 -- Create_All_Components --
11446 ---------------------------
11448 procedure Create_All_Components is
11452 Comp := First_Elmt (Comp_List);
11453 while Present (Comp) loop
11454 Old_C := Node (Comp);
11455 New_C := Create_Component (Old_C);
11459 Constrain_Component_Type
11460 (Old_C, Subt, Decl_Node, Typ, Constraints));
11461 Set_Is_Public (New_C, Is_Public (Subt));
11465 end Create_All_Components;
11467 ----------------------
11468 -- Create_Component --
11469 ----------------------
11471 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
11472 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
11475 if Ekind (Old_Compon) = E_Discriminant
11476 and then Is_Completely_Hidden (Old_Compon)
11478 -- This is a shadow discriminant created for a discriminant of
11479 -- the parent type, which needs to be present in the subtype.
11480 -- Give the shadow discriminant an internal name that cannot
11481 -- conflict with that of visible components.
11483 Set_Chars (New_Compon, New_Internal_Name ('C'));
11486 -- Set the parent so we have a proper link for freezing etc. This is
11487 -- not a real parent pointer, since of course our parent does not own
11488 -- up to us and reference us, we are an illegitimate child of the
11489 -- original parent!
11491 Set_Parent (New_Compon, Parent (Old_Compon));
11493 -- If the old component's Esize was already determined and is a
11494 -- static value, then the new component simply inherits it. Otherwise
11495 -- the old component's size may require run-time determination, but
11496 -- the new component's size still might be statically determinable
11497 -- (if, for example it has a static constraint). In that case we want
11498 -- Layout_Type to recompute the component's size, so we reset its
11499 -- size and positional fields.
11501 if Frontend_Layout_On_Target
11502 and then not Known_Static_Esize (Old_Compon)
11504 Set_Esize (New_Compon, Uint_0);
11505 Init_Normalized_First_Bit (New_Compon);
11506 Init_Normalized_Position (New_Compon);
11507 Init_Normalized_Position_Max (New_Compon);
11510 -- We do not want this node marked as Comes_From_Source, since
11511 -- otherwise it would get first class status and a separate cross-
11512 -- reference line would be generated. Illegitimate children do not
11513 -- rate such recognition.
11515 Set_Comes_From_Source (New_Compon, False);
11517 -- But it is a real entity, and a birth certificate must be properly
11518 -- registered by entering it into the entity list.
11520 Enter_Name (New_Compon);
11523 end Create_Component;
11525 -----------------------
11526 -- Is_Variant_Record --
11527 -----------------------
11529 function Is_Variant_Record (T : Entity_Id) return Boolean is
11531 return Nkind (Parent (T)) = N_Full_Type_Declaration
11532 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
11533 and then Present (Component_List (Type_Definition (Parent (T))))
11536 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
11537 end Is_Variant_Record;
11539 -- Start of processing for Create_Constrained_Components
11542 pragma Assert (Subt /= Base_Type (Subt));
11543 pragma Assert (Typ = Base_Type (Typ));
11545 Set_First_Entity (Subt, Empty);
11546 Set_Last_Entity (Subt, Empty);
11548 -- Check whether constraint is fully static, in which case we can
11549 -- optimize the list of components.
11551 Discr_Val := First_Elmt (Constraints);
11552 while Present (Discr_Val) loop
11553 if not Is_OK_Static_Expression (Node (Discr_Val)) then
11554 Is_Static := False;
11558 Next_Elmt (Discr_Val);
11561 Set_Has_Static_Discriminants (Subt, Is_Static);
11565 -- Inherit the discriminants of the parent type
11567 Add_Discriminants : declare
11573 Old_C := First_Discriminant (Typ);
11575 while Present (Old_C) loop
11576 Num_Disc := Num_Disc + 1;
11577 New_C := Create_Component (Old_C);
11578 Set_Is_Public (New_C, Is_Public (Subt));
11579 Next_Discriminant (Old_C);
11582 -- For an untagged derived subtype, the number of discriminants may
11583 -- be smaller than the number of inherited discriminants, because
11584 -- several of them may be renamed by a single new discriminant or
11585 -- constrained. In this case, add the hidden discriminants back into
11586 -- the subtype, because they need to be present if the optimizer of
11587 -- the GCC 4.x back-end decides to break apart assignments between
11588 -- objects using the parent view into member-wise assignments.
11592 if Is_Derived_Type (Typ)
11593 and then not Is_Tagged_Type (Typ)
11595 Old_C := First_Stored_Discriminant (Typ);
11597 while Present (Old_C) loop
11598 Num_Gird := Num_Gird + 1;
11599 Next_Stored_Discriminant (Old_C);
11603 if Num_Gird > Num_Disc then
11605 -- Find out multiple uses of new discriminants, and add hidden
11606 -- components for the extra renamed discriminants. We recognize
11607 -- multiple uses through the Corresponding_Discriminant of a
11608 -- new discriminant: if it constrains several old discriminants,
11609 -- this field points to the last one in the parent type. The
11610 -- stored discriminants of the derived type have the same name
11611 -- as those of the parent.
11615 New_Discr : Entity_Id;
11616 Old_Discr : Entity_Id;
11619 Constr := First_Elmt (Stored_Constraint (Typ));
11620 Old_Discr := First_Stored_Discriminant (Typ);
11621 while Present (Constr) loop
11622 if Is_Entity_Name (Node (Constr))
11623 and then Ekind (Entity (Node (Constr))) = E_Discriminant
11625 New_Discr := Entity (Node (Constr));
11627 if Chars (Corresponding_Discriminant (New_Discr)) /=
11630 -- The new discriminant has been used to rename a
11631 -- subsequent old discriminant. Introduce a shadow
11632 -- component for the current old discriminant.
11634 New_C := Create_Component (Old_Discr);
11635 Set_Original_Record_Component (New_C, Old_Discr);
11639 -- The constraint has eliminated the old discriminant.
11640 -- Introduce a shadow component.
11642 New_C := Create_Component (Old_Discr);
11643 Set_Original_Record_Component (New_C, Old_Discr);
11646 Next_Elmt (Constr);
11647 Next_Stored_Discriminant (Old_Discr);
11651 end Add_Discriminants;
11654 and then Is_Variant_Record (Typ)
11656 Collect_Fixed_Components (Typ);
11658 Gather_Components (
11660 Component_List (Type_Definition (Parent (Typ))),
11661 Governed_By => Assoc_List,
11663 Report_Errors => Errors);
11664 pragma Assert (not Errors);
11666 Create_All_Components;
11668 -- If the subtype declaration is created for a tagged type derivation
11669 -- with constraints, we retrieve the record definition of the parent
11670 -- type to select the components of the proper variant.
11673 and then Is_Tagged_Type (Typ)
11674 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
11676 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
11677 and then Is_Variant_Record (Parent_Type)
11679 Collect_Fixed_Components (Typ);
11681 Gather_Components (
11683 Component_List (Type_Definition (Parent (Parent_Type))),
11684 Governed_By => Assoc_List,
11686 Report_Errors => Errors);
11687 pragma Assert (not Errors);
11689 -- If the tagged derivation has a type extension, collect all the
11690 -- new components therein.
11693 (Record_Extension_Part (Type_Definition (Parent (Typ))))
11695 Old_C := First_Component (Typ);
11696 while Present (Old_C) loop
11697 if Original_Record_Component (Old_C) = Old_C
11698 and then Chars (Old_C) /= Name_uTag
11699 and then Chars (Old_C) /= Name_uParent
11700 and then Chars (Old_C) /= Name_uController
11702 Append_Elmt (Old_C, Comp_List);
11705 Next_Component (Old_C);
11709 Create_All_Components;
11712 -- If discriminants are not static, or if this is a multi-level type
11713 -- extension, we have to include all components of the parent type.
11715 Old_C := First_Component (Typ);
11716 while Present (Old_C) loop
11717 New_C := Create_Component (Old_C);
11721 Constrain_Component_Type
11722 (Old_C, Subt, Decl_Node, Typ, Constraints));
11723 Set_Is_Public (New_C, Is_Public (Subt));
11725 Next_Component (Old_C);
11730 end Create_Constrained_Components;
11732 ------------------------------------------
11733 -- Decimal_Fixed_Point_Type_Declaration --
11734 ------------------------------------------
11736 procedure Decimal_Fixed_Point_Type_Declaration
11740 Loc : constant Source_Ptr := Sloc (Def);
11741 Digs_Expr : constant Node_Id := Digits_Expression (Def);
11742 Delta_Expr : constant Node_Id := Delta_Expression (Def);
11743 Implicit_Base : Entity_Id;
11750 Check_Restriction (No_Fixed_Point, Def);
11752 -- Create implicit base type
11755 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
11756 Set_Etype (Implicit_Base, Implicit_Base);
11758 -- Analyze and process delta expression
11760 Analyze_And_Resolve (Delta_Expr, Universal_Real);
11762 Check_Delta_Expression (Delta_Expr);
11763 Delta_Val := Expr_Value_R (Delta_Expr);
11765 -- Check delta is power of 10, and determine scale value from it
11771 Scale_Val := Uint_0;
11774 if Val < Ureal_1 then
11775 while Val < Ureal_1 loop
11776 Val := Val * Ureal_10;
11777 Scale_Val := Scale_Val + 1;
11780 if Scale_Val > 18 then
11781 Error_Msg_N ("scale exceeds maximum value of 18", Def);
11782 Scale_Val := UI_From_Int (+18);
11786 while Val > Ureal_1 loop
11787 Val := Val / Ureal_10;
11788 Scale_Val := Scale_Val - 1;
11791 if Scale_Val < -18 then
11792 Error_Msg_N ("scale is less than minimum value of -18", Def);
11793 Scale_Val := UI_From_Int (-18);
11797 if Val /= Ureal_1 then
11798 Error_Msg_N ("delta expression must be a power of 10", Def);
11799 Delta_Val := Ureal_10 ** (-Scale_Val);
11803 -- Set delta, scale and small (small = delta for decimal type)
11805 Set_Delta_Value (Implicit_Base, Delta_Val);
11806 Set_Scale_Value (Implicit_Base, Scale_Val);
11807 Set_Small_Value (Implicit_Base, Delta_Val);
11809 -- Analyze and process digits expression
11811 Analyze_And_Resolve (Digs_Expr, Any_Integer);
11812 Check_Digits_Expression (Digs_Expr);
11813 Digs_Val := Expr_Value (Digs_Expr);
11815 if Digs_Val > 18 then
11816 Digs_Val := UI_From_Int (+18);
11817 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
11820 Set_Digits_Value (Implicit_Base, Digs_Val);
11821 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
11823 -- Set range of base type from digits value for now. This will be
11824 -- expanded to represent the true underlying base range by Freeze.
11826 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
11828 -- Note: We leave size as zero for now, size will be set at freeze
11829 -- time. We have to do this for ordinary fixed-point, because the size
11830 -- depends on the specified small, and we might as well do the same for
11831 -- decimal fixed-point.
11833 pragma Assert (Esize (Implicit_Base) = Uint_0);
11835 -- If there are bounds given in the declaration use them as the
11836 -- bounds of the first named subtype.
11838 if Present (Real_Range_Specification (Def)) then
11840 RRS : constant Node_Id := Real_Range_Specification (Def);
11841 Low : constant Node_Id := Low_Bound (RRS);
11842 High : constant Node_Id := High_Bound (RRS);
11847 Analyze_And_Resolve (Low, Any_Real);
11848 Analyze_And_Resolve (High, Any_Real);
11849 Check_Real_Bound (Low);
11850 Check_Real_Bound (High);
11851 Low_Val := Expr_Value_R (Low);
11852 High_Val := Expr_Value_R (High);
11854 if Low_Val < (-Bound_Val) then
11856 ("range low bound too small for digits value", Low);
11857 Low_Val := -Bound_Val;
11860 if High_Val > Bound_Val then
11862 ("range high bound too large for digits value", High);
11863 High_Val := Bound_Val;
11866 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
11869 -- If no explicit range, use range that corresponds to given
11870 -- digits value. This will end up as the final range for the
11874 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
11877 -- Complete entity for first subtype
11879 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
11880 Set_Etype (T, Implicit_Base);
11881 Set_Size_Info (T, Implicit_Base);
11882 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
11883 Set_Digits_Value (T, Digs_Val);
11884 Set_Delta_Value (T, Delta_Val);
11885 Set_Small_Value (T, Delta_Val);
11886 Set_Scale_Value (T, Scale_Val);
11887 Set_Is_Constrained (T);
11888 end Decimal_Fixed_Point_Type_Declaration;
11890 -----------------------------------
11891 -- Derive_Progenitor_Subprograms --
11892 -----------------------------------
11894 procedure Derive_Progenitor_Subprograms
11895 (Parent_Type : Entity_Id;
11896 Tagged_Type : Entity_Id)
11901 Iface_Elmt : Elmt_Id;
11902 Iface_Subp : Entity_Id;
11903 New_Subp : Entity_Id := Empty;
11904 Prim_Elmt : Elmt_Id;
11909 pragma Assert (Ada_Version >= Ada_05
11910 and then Is_Record_Type (Tagged_Type)
11911 and then Is_Tagged_Type (Tagged_Type)
11912 and then Has_Interfaces (Tagged_Type));
11914 -- Step 1: Transfer to the full-view primitives associated with the
11915 -- partial-view that cover interface primitives. Conceptually this
11916 -- work should be done later by Process_Full_View; done here to
11917 -- simplify its implementation at later stages. It can be safely
11918 -- done here because interfaces must be visible in the partial and
11919 -- private view (RM 7.3(7.3/2)).
11921 -- Small optimization: This work is only required if the parent is
11922 -- abstract. If the tagged type is not abstract, it cannot have
11923 -- abstract primitives (the only entities in the list of primitives of
11924 -- non-abstract tagged types that can reference abstract primitives
11925 -- through its Alias attribute are the internal entities that have
11926 -- attribute Interface_Alias, and these entities are generated later
11927 -- by Freeze_Record_Type).
11929 if In_Private_Part (Current_Scope)
11930 and then Is_Abstract_Type (Parent_Type)
11932 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
11933 while Present (Elmt) loop
11934 Subp := Node (Elmt);
11936 -- At this stage it is not possible to have entities in the list
11937 -- of primitives that have attribute Interface_Alias
11939 pragma Assert (No (Interface_Alias (Subp)));
11941 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
11943 if Is_Interface (Typ) then
11944 E := Find_Primitive_Covering_Interface
11945 (Tagged_Type => Tagged_Type,
11946 Iface_Prim => Subp);
11949 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
11951 Replace_Elmt (Elmt, E);
11952 Remove_Homonym (Subp);
11960 -- Step 2: Add primitives of progenitors that are not implemented by
11961 -- parents of Tagged_Type
11963 if Present (Interfaces (Base_Type (Tagged_Type))) then
11964 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
11965 while Present (Iface_Elmt) loop
11966 Iface := Node (Iface_Elmt);
11968 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
11969 while Present (Prim_Elmt) loop
11970 Iface_Subp := Node (Prim_Elmt);
11972 -- Exclude derivation of predefined primitives except those
11973 -- that come from source. Required to catch declarations of
11974 -- equality operators of interfaces. For example:
11976 -- type Iface is interface;
11977 -- function "=" (Left, Right : Iface) return Boolean;
11979 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
11980 or else Comes_From_Source (Iface_Subp)
11982 E := Find_Primitive_Covering_Interface
11983 (Tagged_Type => Tagged_Type,
11984 Iface_Prim => Iface_Subp);
11986 -- If not found we derive a new primitive leaving its alias
11987 -- attribute referencing the interface primitive
11991 (New_Subp, Iface_Subp, Tagged_Type, Iface);
11993 -- Propagate to the full view interface entities associated
11994 -- with the partial view
11996 elsif In_Private_Part (Current_Scope)
11997 and then Present (Alias (E))
11998 and then Alias (E) = Iface_Subp
12000 List_Containing (Parent (E)) /=
12001 Private_Declarations
12003 (Unit_Declaration_Node (Current_Scope)))
12005 Append_Elmt (E, Primitive_Operations (Tagged_Type));
12009 Next_Elmt (Prim_Elmt);
12012 Next_Elmt (Iface_Elmt);
12015 end Derive_Progenitor_Subprograms;
12017 -----------------------
12018 -- Derive_Subprogram --
12019 -----------------------
12021 procedure Derive_Subprogram
12022 (New_Subp : in out Entity_Id;
12023 Parent_Subp : Entity_Id;
12024 Derived_Type : Entity_Id;
12025 Parent_Type : Entity_Id;
12026 Actual_Subp : Entity_Id := Empty)
12028 Formal : Entity_Id;
12029 -- Formal parameter of parent primitive operation
12031 Formal_Of_Actual : Entity_Id;
12032 -- Formal parameter of actual operation, when the derivation is to
12033 -- create a renaming for a primitive operation of an actual in an
12036 New_Formal : Entity_Id;
12037 -- Formal of inherited operation
12039 Visible_Subp : Entity_Id := Parent_Subp;
12041 function Is_Private_Overriding return Boolean;
12042 -- If Subp is a private overriding of a visible operation, the inherited
12043 -- operation derives from the overridden op (even though its body is the
12044 -- overriding one) and the inherited operation is visible now. See
12045 -- sem_disp to see the full details of the handling of the overridden
12046 -- subprogram, which is removed from the list of primitive operations of
12047 -- the type. The overridden subprogram is saved locally in Visible_Subp,
12048 -- and used to diagnose abstract operations that need overriding in the
12051 procedure Replace_Type (Id, New_Id : Entity_Id);
12052 -- When the type is an anonymous access type, create a new access type
12053 -- designating the derived type.
12055 procedure Set_Derived_Name;
12056 -- This procedure sets the appropriate Chars name for New_Subp. This
12057 -- is normally just a copy of the parent name. An exception arises for
12058 -- type support subprograms, where the name is changed to reflect the
12059 -- name of the derived type, e.g. if type foo is derived from type bar,
12060 -- then a procedure barDA is derived with a name fooDA.
12062 ---------------------------
12063 -- Is_Private_Overriding --
12064 ---------------------------
12066 function Is_Private_Overriding return Boolean is
12070 -- If the parent is not a dispatching operation there is no
12071 -- need to investigate overridings
12073 if not Is_Dispatching_Operation (Parent_Subp) then
12077 -- The visible operation that is overridden is a homonym of the
12078 -- parent subprogram. We scan the homonym chain to find the one
12079 -- whose alias is the subprogram we are deriving.
12081 Prev := Current_Entity (Parent_Subp);
12082 while Present (Prev) loop
12083 if Ekind (Prev) = Ekind (Parent_Subp)
12084 and then Alias (Prev) = Parent_Subp
12085 and then Scope (Parent_Subp) = Scope (Prev)
12086 and then not Is_Hidden (Prev)
12088 Visible_Subp := Prev;
12092 Prev := Homonym (Prev);
12096 end Is_Private_Overriding;
12102 procedure Replace_Type (Id, New_Id : Entity_Id) is
12103 Acc_Type : Entity_Id;
12104 Par : constant Node_Id := Parent (Derived_Type);
12107 -- When the type is an anonymous access type, create a new access
12108 -- type designating the derived type. This itype must be elaborated
12109 -- at the point of the derivation, not on subsequent calls that may
12110 -- be out of the proper scope for Gigi, so we insert a reference to
12111 -- it after the derivation.
12113 if Ekind (Etype (Id)) = E_Anonymous_Access_Type then
12115 Desig_Typ : Entity_Id := Designated_Type (Etype (Id));
12118 if Ekind (Desig_Typ) = E_Record_Type_With_Private
12119 and then Present (Full_View (Desig_Typ))
12120 and then not Is_Private_Type (Parent_Type)
12122 Desig_Typ := Full_View (Desig_Typ);
12125 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
12127 -- Ada 2005 (AI-251): Handle also derivations of abstract
12128 -- interface primitives.
12130 or else (Is_Interface (Desig_Typ)
12131 and then not Is_Class_Wide_Type (Desig_Typ))
12133 Acc_Type := New_Copy (Etype (Id));
12134 Set_Etype (Acc_Type, Acc_Type);
12135 Set_Scope (Acc_Type, New_Subp);
12137 -- Compute size of anonymous access type
12139 if Is_Array_Type (Desig_Typ)
12140 and then not Is_Constrained (Desig_Typ)
12142 Init_Size (Acc_Type, 2 * System_Address_Size);
12144 Init_Size (Acc_Type, System_Address_Size);
12147 Init_Alignment (Acc_Type);
12148 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
12150 Set_Etype (New_Id, Acc_Type);
12151 Set_Scope (New_Id, New_Subp);
12153 -- Create a reference to it
12154 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
12157 Set_Etype (New_Id, Etype (Id));
12161 elsif Base_Type (Etype (Id)) = Base_Type (Parent_Type)
12163 (Ekind (Etype (Id)) = E_Record_Type_With_Private
12164 and then Present (Full_View (Etype (Id)))
12166 Base_Type (Full_View (Etype (Id))) = Base_Type (Parent_Type))
12168 -- Constraint checks on formals are generated during expansion,
12169 -- based on the signature of the original subprogram. The bounds
12170 -- of the derived type are not relevant, and thus we can use
12171 -- the base type for the formals. However, the return type may be
12172 -- used in a context that requires that the proper static bounds
12173 -- be used (a case statement, for example) and for those cases
12174 -- we must use the derived type (first subtype), not its base.
12176 -- If the derived_type_definition has no constraints, we know that
12177 -- the derived type has the same constraints as the first subtype
12178 -- of the parent, and we can also use it rather than its base,
12179 -- which can lead to more efficient code.
12181 if Etype (Id) = Parent_Type then
12182 if Is_Scalar_Type (Parent_Type)
12184 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
12186 Set_Etype (New_Id, Derived_Type);
12188 elsif Nkind (Par) = N_Full_Type_Declaration
12190 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
12193 (Subtype_Indication (Type_Definition (Par)))
12195 Set_Etype (New_Id, Derived_Type);
12198 Set_Etype (New_Id, Base_Type (Derived_Type));
12202 Set_Etype (New_Id, Base_Type (Derived_Type));
12205 -- Ada 2005 (AI-251): Handle derivations of abstract interface
12208 elsif Is_Interface (Etype (Id))
12209 and then not Is_Class_Wide_Type (Etype (Id))
12210 and then Is_Progenitor (Etype (Id), Derived_Type)
12212 Set_Etype (New_Id, Derived_Type);
12215 Set_Etype (New_Id, Etype (Id));
12219 ----------------------
12220 -- Set_Derived_Name --
12221 ----------------------
12223 procedure Set_Derived_Name is
12224 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
12226 if Nm = TSS_Null then
12227 Set_Chars (New_Subp, Chars (Parent_Subp));
12229 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
12231 end Set_Derived_Name;
12235 Parent_Overrides_Interface_Primitive : Boolean := False;
12237 -- Start of processing for Derive_Subprogram
12241 New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
12242 Set_Ekind (New_Subp, Ekind (Parent_Subp));
12244 -- Check whether the parent overrides an interface primitive
12246 if Is_Overriding_Operation (Parent_Subp) then
12248 E : Entity_Id := Parent_Subp;
12250 while Present (Overridden_Operation (E)) loop
12251 E := Ultimate_Alias (Overridden_Operation (E));
12254 Parent_Overrides_Interface_Primitive :=
12255 Is_Dispatching_Operation (E)
12256 and then Present (Find_Dispatching_Type (E))
12257 and then Is_Interface (Find_Dispatching_Type (E));
12261 -- Check whether the inherited subprogram is a private operation that
12262 -- should be inherited but not yet made visible. Such subprograms can
12263 -- become visible at a later point (e.g., the private part of a public
12264 -- child unit) via Declare_Inherited_Private_Subprograms. If the
12265 -- following predicate is true, then this is not such a private
12266 -- operation and the subprogram simply inherits the name of the parent
12267 -- subprogram. Note the special check for the names of controlled
12268 -- operations, which are currently exempted from being inherited with
12269 -- a hidden name because they must be findable for generation of
12270 -- implicit run-time calls.
12272 if not Is_Hidden (Parent_Subp)
12273 or else Is_Internal (Parent_Subp)
12274 or else Is_Private_Overriding
12275 or else Is_Internal_Name (Chars (Parent_Subp))
12276 or else Chars (Parent_Subp) = Name_Initialize
12277 or else Chars (Parent_Subp) = Name_Adjust
12278 or else Chars (Parent_Subp) = Name_Finalize
12282 -- An inherited dispatching equality will be overridden by an internally
12283 -- generated one, or by an explicit one, so preserve its name and thus
12284 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
12285 -- private operation it may become invisible if the full view has
12286 -- progenitors, and the dispatch table will be malformed.
12287 -- We check that the type is limited to handle the anomalous declaration
12288 -- of Limited_Controlled, which is derived from a non-limited type, and
12289 -- which is handled specially elsewhere as well.
12291 elsif Chars (Parent_Subp) = Name_Op_Eq
12292 and then Is_Dispatching_Operation (Parent_Subp)
12293 and then Etype (Parent_Subp) = Standard_Boolean
12294 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
12296 Etype (First_Formal (Parent_Subp)) =
12297 Etype (Next_Formal (First_Formal (Parent_Subp)))
12301 -- If parent is hidden, this can be a regular derivation if the
12302 -- parent is immediately visible in a non-instantiating context,
12303 -- or if we are in the private part of an instance. This test
12304 -- should still be refined ???
12306 -- The test for In_Instance_Not_Visible avoids inheriting the derived
12307 -- operation as a non-visible operation in cases where the parent
12308 -- subprogram might not be visible now, but was visible within the
12309 -- original generic, so it would be wrong to make the inherited
12310 -- subprogram non-visible now. (Not clear if this test is fully
12311 -- correct; are there any cases where we should declare the inherited
12312 -- operation as not visible to avoid it being overridden, e.g., when
12313 -- the parent type is a generic actual with private primitives ???)
12315 -- (they should be treated the same as other private inherited
12316 -- subprograms, but it's not clear how to do this cleanly). ???
12318 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
12319 and then Is_Immediately_Visible (Parent_Subp)
12320 and then not In_Instance)
12321 or else In_Instance_Not_Visible
12325 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
12326 -- overrides an interface primitive because interface primitives
12327 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
12329 elsif Parent_Overrides_Interface_Primitive then
12332 -- Otherwise, the type is inheriting a private operation, so enter
12333 -- it with a special name so it can't be overridden.
12336 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
12339 Set_Parent (New_Subp, Parent (Derived_Type));
12341 if Present (Actual_Subp) then
12342 Replace_Type (Actual_Subp, New_Subp);
12344 Replace_Type (Parent_Subp, New_Subp);
12347 Conditional_Delay (New_Subp, Parent_Subp);
12349 -- If we are creating a renaming for a primitive operation of an
12350 -- actual of a generic derived type, we must examine the signature
12351 -- of the actual primitive, not that of the generic formal, which for
12352 -- example may be an interface. However the name and initial value
12353 -- of the inherited operation are those of the formal primitive.
12355 Formal := First_Formal (Parent_Subp);
12357 if Present (Actual_Subp) then
12358 Formal_Of_Actual := First_Formal (Actual_Subp);
12360 Formal_Of_Actual := Empty;
12363 while Present (Formal) loop
12364 New_Formal := New_Copy (Formal);
12366 -- Normally we do not go copying parents, but in the case of
12367 -- formals, we need to link up to the declaration (which is the
12368 -- parameter specification), and it is fine to link up to the
12369 -- original formal's parameter specification in this case.
12371 Set_Parent (New_Formal, Parent (Formal));
12372 Append_Entity (New_Formal, New_Subp);
12374 if Present (Formal_Of_Actual) then
12375 Replace_Type (Formal_Of_Actual, New_Formal);
12376 Next_Formal (Formal_Of_Actual);
12378 Replace_Type (Formal, New_Formal);
12381 Next_Formal (Formal);
12384 -- If this derivation corresponds to a tagged generic actual, then
12385 -- primitive operations rename those of the actual. Otherwise the
12386 -- primitive operations rename those of the parent type, If the parent
12387 -- renames an intrinsic operator, so does the new subprogram. We except
12388 -- concatenation, which is always properly typed, and does not get
12389 -- expanded as other intrinsic operations.
12391 if No (Actual_Subp) then
12392 if Is_Intrinsic_Subprogram (Parent_Subp) then
12393 Set_Is_Intrinsic_Subprogram (New_Subp);
12395 if Present (Alias (Parent_Subp))
12396 and then Chars (Parent_Subp) /= Name_Op_Concat
12398 Set_Alias (New_Subp, Alias (Parent_Subp));
12400 Set_Alias (New_Subp, Parent_Subp);
12404 Set_Alias (New_Subp, Parent_Subp);
12408 Set_Alias (New_Subp, Actual_Subp);
12411 -- Derived subprograms of a tagged type must inherit the convention
12412 -- of the parent subprogram (a requirement of AI-117). Derived
12413 -- subprograms of untagged types simply get convention Ada by default.
12415 if Is_Tagged_Type (Derived_Type) then
12416 Set_Convention (New_Subp, Convention (Parent_Subp));
12419 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
12420 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
12422 if Ekind (Parent_Subp) = E_Procedure then
12423 Set_Is_Valued_Procedure
12424 (New_Subp, Is_Valued_Procedure (Parent_Subp));
12427 -- No_Return must be inherited properly. If this is overridden in the
12428 -- case of a dispatching operation, then a check is made in Sem_Disp
12429 -- that the overriding operation is also No_Return (no such check is
12430 -- required for the case of non-dispatching operation.
12432 Set_No_Return (New_Subp, No_Return (Parent_Subp));
12434 -- A derived function with a controlling result is abstract. If the
12435 -- Derived_Type is a nonabstract formal generic derived type, then
12436 -- inherited operations are not abstract: the required check is done at
12437 -- instantiation time. If the derivation is for a generic actual, the
12438 -- function is not abstract unless the actual is.
12440 if Is_Generic_Type (Derived_Type)
12441 and then not Is_Abstract_Type (Derived_Type)
12445 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
12446 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
12448 elsif Ada_Version >= Ada_05
12449 and then (Is_Abstract_Subprogram (Alias (New_Subp))
12450 or else (Is_Tagged_Type (Derived_Type)
12451 and then Etype (New_Subp) = Derived_Type
12452 and then not Is_Null_Extension (Derived_Type))
12453 or else (Is_Tagged_Type (Derived_Type)
12454 and then Ekind (Etype (New_Subp)) =
12455 E_Anonymous_Access_Type
12456 and then Designated_Type (Etype (New_Subp)) =
12458 and then not Is_Null_Extension (Derived_Type)))
12459 and then No (Actual_Subp)
12461 if not Is_Tagged_Type (Derived_Type)
12462 or else Is_Abstract_Type (Derived_Type)
12463 or else Is_Abstract_Subprogram (Alias (New_Subp))
12465 Set_Is_Abstract_Subprogram (New_Subp);
12467 Set_Requires_Overriding (New_Subp);
12470 elsif Ada_Version < Ada_05
12471 and then (Is_Abstract_Subprogram (Alias (New_Subp))
12472 or else (Is_Tagged_Type (Derived_Type)
12473 and then Etype (New_Subp) = Derived_Type
12474 and then No (Actual_Subp)))
12476 Set_Is_Abstract_Subprogram (New_Subp);
12478 -- Finally, if the parent type is abstract we must verify that all
12479 -- inherited operations are either non-abstract or overridden, or that
12480 -- the derived type itself is abstract (this check is performed at the
12481 -- end of a package declaration, in Check_Abstract_Overriding). A
12482 -- private overriding in the parent type will not be visible in the
12483 -- derivation if we are not in an inner package or in a child unit of
12484 -- the parent type, in which case the abstractness of the inherited
12485 -- operation is carried to the new subprogram.
12487 elsif Is_Abstract_Type (Parent_Type)
12488 and then not In_Open_Scopes (Scope (Parent_Type))
12489 and then Is_Private_Overriding
12490 and then Is_Abstract_Subprogram (Visible_Subp)
12492 if No (Actual_Subp) then
12493 Set_Alias (New_Subp, Visible_Subp);
12494 Set_Is_Abstract_Subprogram
12497 -- If this is a derivation for an instance of a formal derived
12498 -- type, abstractness comes from the primitive operation of the
12499 -- actual, not from the operation inherited from the ancestor.
12501 Set_Is_Abstract_Subprogram
12502 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
12506 New_Overloaded_Entity (New_Subp, Derived_Type);
12508 -- Check for case of a derived subprogram for the instantiation of a
12509 -- formal derived tagged type, if so mark the subprogram as dispatching
12510 -- and inherit the dispatching attributes of the parent subprogram. The
12511 -- derived subprogram is effectively renaming of the actual subprogram,
12512 -- so it needs to have the same attributes as the actual.
12514 if Present (Actual_Subp)
12515 and then Is_Dispatching_Operation (Parent_Subp)
12517 Set_Is_Dispatching_Operation (New_Subp);
12519 if Present (DTC_Entity (Parent_Subp)) then
12520 Set_DTC_Entity (New_Subp, DTC_Entity (Parent_Subp));
12521 Set_DT_Position (New_Subp, DT_Position (Parent_Subp));
12525 -- Indicate that a derived subprogram does not require a body and that
12526 -- it does not require processing of default expressions.
12528 Set_Has_Completion (New_Subp);
12529 Set_Default_Expressions_Processed (New_Subp);
12531 if Ekind (New_Subp) = E_Function then
12532 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
12534 end Derive_Subprogram;
12536 ------------------------
12537 -- Derive_Subprograms --
12538 ------------------------
12540 procedure Derive_Subprograms
12541 (Parent_Type : Entity_Id;
12542 Derived_Type : Entity_Id;
12543 Generic_Actual : Entity_Id := Empty)
12545 Op_List : constant Elist_Id :=
12546 Collect_Primitive_Operations (Parent_Type);
12548 function Check_Derived_Type return Boolean;
12549 -- Check that all primitive inherited from Parent_Type are found in
12550 -- the list of primitives of Derived_Type exactly in the same order.
12552 function Check_Derived_Type return Boolean is
12556 New_Subp : Entity_Id;
12561 -- Traverse list of entities in the current scope searching for
12562 -- an incomplete type whose full-view is derived type
12564 E := First_Entity (Scope (Derived_Type));
12566 and then E /= Derived_Type
12568 if Ekind (E) = E_Incomplete_Type
12569 and then Present (Full_View (E))
12570 and then Full_View (E) = Derived_Type
12572 -- Disable this test if Derived_Type completes an incomplete
12573 -- type because in such case more primitives can be added
12574 -- later to the list of primitives of Derived_Type by routine
12575 -- Process_Incomplete_Dependents
12580 E := Next_Entity (E);
12583 List := Collect_Primitive_Operations (Derived_Type);
12584 Elmt := First_Elmt (List);
12586 Op_Elmt := First_Elmt (Op_List);
12587 while Present (Op_Elmt) loop
12588 Subp := Node (Op_Elmt);
12589 New_Subp := Node (Elmt);
12591 -- At this early stage Derived_Type has no entities with attribute
12592 -- Interface_Alias. In addition, such primitives are always
12593 -- located at the end of the list of primitives of Parent_Type.
12594 -- Therefore, if found we can safely stop processing pending
12597 exit when Present (Interface_Alias (Subp));
12599 -- Handle hidden entities
12601 if not Is_Predefined_Dispatching_Operation (Subp)
12602 and then Is_Hidden (Subp)
12604 if Present (New_Subp)
12605 and then Primitive_Names_Match (Subp, New_Subp)
12611 if not Present (New_Subp)
12612 or else Ekind (Subp) /= Ekind (New_Subp)
12613 or else not Primitive_Names_Match (Subp, New_Subp)
12621 Next_Elmt (Op_Elmt);
12625 end Check_Derived_Type;
12629 Alias_Subp : Entity_Id;
12630 Act_List : Elist_Id;
12631 Act_Elmt : Elmt_Id := No_Elmt;
12632 Act_Subp : Entity_Id := Empty;
12634 Need_Search : Boolean := False;
12635 New_Subp : Entity_Id := Empty;
12636 Parent_Base : Entity_Id;
12639 -- Start of processing for Derive_Subprograms
12642 if Ekind (Parent_Type) = E_Record_Type_With_Private
12643 and then Has_Discriminants (Parent_Type)
12644 and then Present (Full_View (Parent_Type))
12646 Parent_Base := Full_View (Parent_Type);
12648 Parent_Base := Parent_Type;
12651 if Present (Generic_Actual) then
12652 Act_List := Collect_Primitive_Operations (Generic_Actual);
12653 Act_Elmt := First_Elmt (Act_List);
12656 -- Derive primitives inherited from the parent. Note that if the generic
12657 -- actual is present, this is not really a type derivation, it is a
12658 -- completion within an instance.
12660 -- Case 1: Derived_Type does not implement interfaces
12662 if not Is_Tagged_Type (Derived_Type)
12663 or else (not Has_Interfaces (Derived_Type)
12664 and then not (Present (Generic_Actual)
12666 Has_Interfaces (Generic_Actual)))
12668 Elmt := First_Elmt (Op_List);
12669 while Present (Elmt) loop
12670 Subp := Node (Elmt);
12672 -- Literals are derived earlier in the process of building the
12673 -- derived type, and are skipped here.
12675 if Ekind (Subp) = E_Enumeration_Literal then
12678 -- The actual is a direct descendant and the common primitive
12679 -- operations appear in the same order.
12681 -- If the generic parent type is present, the derived type is an
12682 -- instance of a formal derived type, and within the instance its
12683 -- operations are those of the actual. We derive from the formal
12684 -- type but make the inherited operations aliases of the
12685 -- corresponding operations of the actual.
12689 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
12691 if Present (Act_Elmt) then
12692 Next_Elmt (Act_Elmt);
12699 -- Case 2: Derived_Type implements interfaces
12702 -- If the parent type has no predefined primitives we remove
12703 -- predefined primitives from the list of primitives of generic
12704 -- actual to simplify the complexity of this algorithm.
12706 if Present (Generic_Actual) then
12708 Has_Predefined_Primitives : Boolean := False;
12711 -- Check if the parent type has predefined primitives
12713 Elmt := First_Elmt (Op_List);
12714 while Present (Elmt) loop
12715 Subp := Node (Elmt);
12717 if Is_Predefined_Dispatching_Operation (Subp)
12718 and then not Comes_From_Source (Ultimate_Alias (Subp))
12720 Has_Predefined_Primitives := True;
12727 -- Remove predefined primitives of Generic_Actual. We must use
12728 -- an auxiliary list because in case of tagged types the value
12729 -- returned by Collect_Primitive_Operations is the value stored
12730 -- in its Primitive_Operations attribute (and we don't want to
12731 -- modify its current contents).
12733 if not Has_Predefined_Primitives then
12735 Aux_List : constant Elist_Id := New_Elmt_List;
12738 Elmt := First_Elmt (Act_List);
12739 while Present (Elmt) loop
12740 Subp := Node (Elmt);
12742 if not Is_Predefined_Dispatching_Operation (Subp)
12743 or else Comes_From_Source (Subp)
12745 Append_Elmt (Subp, Aux_List);
12751 Act_List := Aux_List;
12755 Act_Elmt := First_Elmt (Act_List);
12756 Act_Subp := Node (Act_Elmt);
12760 -- Stage 1: If the generic actual is not present we derive the
12761 -- primitives inherited from the parent type. If the generic parent
12762 -- type is present, the derived type is an instance of a formal
12763 -- derived type, and within the instance its operations are those of
12764 -- the actual. We derive from the formal type but make the inherited
12765 -- operations aliases of the corresponding operations of the actual.
12767 Elmt := First_Elmt (Op_List);
12768 while Present (Elmt) loop
12769 Subp := Node (Elmt);
12770 Alias_Subp := Ultimate_Alias (Subp);
12772 -- At this early stage Derived_Type has no entities with attribute
12773 -- Interface_Alias. In addition, such primitives are always
12774 -- located at the end of the list of primitives of Parent_Type.
12775 -- Therefore, if found we can safely stop processing pending
12778 exit when Present (Interface_Alias (Subp));
12780 -- If the generic actual is present find the corresponding
12781 -- operation in the generic actual. If the parent type is a
12782 -- direct ancestor of the derived type then, even if it is an
12783 -- interface, the operations are inherited from the primary
12784 -- dispatch table and are in the proper order. If we detect here
12785 -- that primitives are not in the same order we traverse the list
12786 -- of primitive operations of the actual to find the one that
12787 -- implements the interface primitive.
12791 (Present (Generic_Actual)
12792 and then Present (Act_Subp)
12793 and then not Primitive_Names_Match (Subp, Act_Subp))
12795 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual));
12796 pragma Assert (Is_Interface (Parent_Base));
12798 -- Remember that we need searching for all the pending
12801 Need_Search := True;
12803 -- Handle entities associated with interface primitives
12805 if Present (Alias (Subp))
12806 and then Is_Interface (Find_Dispatching_Type (Alias (Subp)))
12807 and then not Is_Predefined_Dispatching_Operation (Subp)
12810 Find_Primitive_Covering_Interface
12811 (Tagged_Type => Generic_Actual,
12812 Iface_Prim => Subp);
12814 -- Handle predefined primitives plus the rest of user-defined
12818 Act_Elmt := First_Elmt (Act_List);
12819 while Present (Act_Elmt) loop
12820 Act_Subp := Node (Act_Elmt);
12822 exit when Primitive_Names_Match (Subp, Act_Subp)
12823 and then Type_Conformant (Subp, Act_Subp,
12824 Skip_Controlling_Formals => True)
12825 and then No (Interface_Alias (Act_Subp));
12827 Next_Elmt (Act_Elmt);
12832 -- Case 1: If the parent is a limited interface then it has the
12833 -- predefined primitives of synchronized interfaces. However, the
12834 -- actual type may be a non-limited type and hence it does not
12835 -- have such primitives.
12837 if Present (Generic_Actual)
12838 and then not Present (Act_Subp)
12839 and then Is_Limited_Interface (Parent_Base)
12840 and then Is_Predefined_Interface_Primitive (Subp)
12844 -- Case 2: Inherit entities associated with interfaces that
12845 -- were not covered by the parent type. We exclude here null
12846 -- interface primitives because they do not need special
12849 elsif Present (Alias (Subp))
12850 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
12852 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
12853 and then Null_Present (Parent (Alias_Subp)))
12856 (New_Subp => New_Subp,
12857 Parent_Subp => Alias_Subp,
12858 Derived_Type => Derived_Type,
12859 Parent_Type => Find_Dispatching_Type (Alias_Subp),
12860 Actual_Subp => Act_Subp);
12862 if No (Generic_Actual) then
12863 Set_Alias (New_Subp, Subp);
12866 -- Case 3: Common derivation
12870 (New_Subp => New_Subp,
12871 Parent_Subp => Subp,
12872 Derived_Type => Derived_Type,
12873 Parent_Type => Parent_Base,
12874 Actual_Subp => Act_Subp);
12877 -- No need to update Act_Elm if we must search for the
12878 -- corresponding operation in the generic actual
12881 and then Present (Act_Elmt)
12883 Next_Elmt (Act_Elmt);
12884 Act_Subp := Node (Act_Elmt);
12890 -- Inherit additional operations from progenitors. If the derived
12891 -- type is a generic actual, there are not new primitive operations
12892 -- for the type because it has those of the actual, and therefore
12893 -- nothing needs to be done. The renamings generated above are not
12894 -- primitive operations, and their purpose is simply to make the
12895 -- proper operations visible within an instantiation.
12897 if No (Generic_Actual) then
12898 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
12902 -- Final check: Direct descendants must have their primitives in the
12903 -- same order. We exclude from this test non-tagged types and instances
12904 -- of formal derived types. We skip this test if we have already
12905 -- reported serious errors in the sources.
12907 pragma Assert (not Is_Tagged_Type (Derived_Type)
12908 or else Present (Generic_Actual)
12909 or else Serious_Errors_Detected > 0
12910 or else Check_Derived_Type);
12911 end Derive_Subprograms;
12913 --------------------------------
12914 -- Derived_Standard_Character --
12915 --------------------------------
12917 procedure Derived_Standard_Character
12919 Parent_Type : Entity_Id;
12920 Derived_Type : Entity_Id)
12922 Loc : constant Source_Ptr := Sloc (N);
12923 Def : constant Node_Id := Type_Definition (N);
12924 Indic : constant Node_Id := Subtype_Indication (Def);
12925 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
12926 Implicit_Base : constant Entity_Id :=
12928 (E_Enumeration_Type, N, Derived_Type, 'B');
12934 Discard_Node (Process_Subtype (Indic, N));
12936 Set_Etype (Implicit_Base, Parent_Base);
12937 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
12938 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
12940 Set_Is_Character_Type (Implicit_Base, True);
12941 Set_Has_Delayed_Freeze (Implicit_Base);
12943 -- The bounds of the implicit base are the bounds of the parent base.
12944 -- Note that their type is the parent base.
12946 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
12947 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
12949 Set_Scalar_Range (Implicit_Base,
12952 High_Bound => Hi));
12954 Conditional_Delay (Derived_Type, Parent_Type);
12956 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
12957 Set_Etype (Derived_Type, Implicit_Base);
12958 Set_Size_Info (Derived_Type, Parent_Type);
12960 if Unknown_RM_Size (Derived_Type) then
12961 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
12964 Set_Is_Character_Type (Derived_Type, True);
12966 if Nkind (Indic) /= N_Subtype_Indication then
12968 -- If no explicit constraint, the bounds are those
12969 -- of the parent type.
12971 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
12972 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
12973 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
12976 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
12978 -- Because the implicit base is used in the conversion of the bounds, we
12979 -- have to freeze it now. This is similar to what is done for numeric
12980 -- types, and it equally suspicious, but otherwise a non-static bound
12981 -- will have a reference to an unfrozen type, which is rejected by Gigi
12982 -- (???). This requires specific care for definition of stream
12983 -- attributes. For details, see comments at the end of
12984 -- Build_Derived_Numeric_Type.
12986 Freeze_Before (N, Implicit_Base);
12987 end Derived_Standard_Character;
12989 ------------------------------
12990 -- Derived_Type_Declaration --
12991 ------------------------------
12993 procedure Derived_Type_Declaration
12996 Is_Completion : Boolean)
12998 Parent_Type : Entity_Id;
13000 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
13001 -- Check whether the parent type is a generic formal, or derives
13002 -- directly or indirectly from one.
13004 ------------------------
13005 -- Comes_From_Generic --
13006 ------------------------
13008 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
13010 if Is_Generic_Type (Typ) then
13013 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
13016 elsif Is_Private_Type (Typ)
13017 and then Present (Full_View (Typ))
13018 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
13022 elsif Is_Generic_Actual_Type (Typ) then
13028 end Comes_From_Generic;
13032 Def : constant Node_Id := Type_Definition (N);
13033 Iface_Def : Node_Id;
13034 Indic : constant Node_Id := Subtype_Indication (Def);
13035 Extension : constant Node_Id := Record_Extension_Part (Def);
13036 Parent_Node : Node_Id;
13037 Parent_Scope : Entity_Id;
13040 -- Start of processing for Derived_Type_Declaration
13043 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
13045 -- Ada 2005 (AI-251): In case of interface derivation check that the
13046 -- parent is also an interface.
13048 if Interface_Present (Def) then
13049 if not Is_Interface (Parent_Type) then
13050 Diagnose_Interface (Indic, Parent_Type);
13053 Parent_Node := Parent (Base_Type (Parent_Type));
13054 Iface_Def := Type_Definition (Parent_Node);
13056 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
13057 -- other limited interfaces.
13059 if Limited_Present (Def) then
13060 if Limited_Present (Iface_Def) then
13063 elsif Protected_Present (Iface_Def) then
13065 ("descendant of& must be declared"
13066 & " as a protected interface",
13069 elsif Synchronized_Present (Iface_Def) then
13071 ("descendant of& must be declared"
13072 & " as a synchronized interface",
13075 elsif Task_Present (Iface_Def) then
13077 ("descendant of& must be declared as a task interface",
13082 ("(Ada 2005) limited interface cannot "
13083 & "inherit from non-limited interface", Indic);
13086 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
13087 -- from non-limited or limited interfaces.
13089 elsif not Protected_Present (Def)
13090 and then not Synchronized_Present (Def)
13091 and then not Task_Present (Def)
13093 if Limited_Present (Iface_Def) then
13096 elsif Protected_Present (Iface_Def) then
13098 ("descendant of& must be declared"
13099 & " as a protected interface",
13102 elsif Synchronized_Present (Iface_Def) then
13104 ("descendant of& must be declared"
13105 & " as a synchronized interface",
13108 elsif Task_Present (Iface_Def) then
13110 ("descendant of& must be declared as a task interface",
13119 if Is_Tagged_Type (Parent_Type)
13120 and then Is_Concurrent_Type (Parent_Type)
13121 and then not Is_Interface (Parent_Type)
13124 ("parent type of a record extension cannot be "
13125 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
13126 Set_Etype (T, Any_Type);
13130 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
13133 if Is_Tagged_Type (Parent_Type)
13134 and then Is_Non_Empty_List (Interface_List (Def))
13141 Intf := First (Interface_List (Def));
13142 while Present (Intf) loop
13143 T := Find_Type_Of_Subtype_Indic (Intf);
13145 if not Is_Interface (T) then
13146 Diagnose_Interface (Intf, T);
13148 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
13149 -- a limited type from having a nonlimited progenitor.
13151 elsif (Limited_Present (Def)
13152 or else (not Is_Interface (Parent_Type)
13153 and then Is_Limited_Type (Parent_Type)))
13154 and then not Is_Limited_Interface (T)
13157 ("progenitor interface& of limited type must be limited",
13166 if Parent_Type = Any_Type
13167 or else Etype (Parent_Type) = Any_Type
13168 or else (Is_Class_Wide_Type (Parent_Type)
13169 and then Etype (Parent_Type) = T)
13171 -- If Parent_Type is undefined or illegal, make new type into a
13172 -- subtype of Any_Type, and set a few attributes to prevent cascaded
13173 -- errors. If this is a self-definition, emit error now.
13176 or else T = Etype (Parent_Type)
13178 Error_Msg_N ("type cannot be used in its own definition", Indic);
13181 Set_Ekind (T, Ekind (Parent_Type));
13182 Set_Etype (T, Any_Type);
13183 Set_Scalar_Range (T, Scalar_Range (Any_Type));
13185 if Is_Tagged_Type (T) then
13186 Set_Primitive_Operations (T, New_Elmt_List);
13192 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
13193 -- an interface is special because the list of interfaces in the full
13194 -- view can be given in any order. For example:
13196 -- type A is interface;
13197 -- type B is interface and A;
13198 -- type D is new B with private;
13200 -- type D is new A and B with null record; -- 1 --
13202 -- In this case we perform the following transformation of -1-:
13204 -- type D is new B and A with null record;
13206 -- If the parent of the full-view covers the parent of the partial-view
13207 -- we have two possible cases:
13209 -- 1) They have the same parent
13210 -- 2) The parent of the full-view implements some further interfaces
13212 -- In both cases we do not need to perform the transformation. In the
13213 -- first case the source program is correct and the transformation is
13214 -- not needed; in the second case the source program does not fulfill
13215 -- the no-hidden interfaces rule (AI-396) and the error will be reported
13218 -- This transformation not only simplifies the rest of the analysis of
13219 -- this type declaration but also simplifies the correct generation of
13220 -- the object layout to the expander.
13222 if In_Private_Part (Current_Scope)
13223 and then Is_Interface (Parent_Type)
13227 Partial_View : Entity_Id;
13228 Partial_View_Parent : Entity_Id;
13229 New_Iface : Node_Id;
13232 -- Look for the associated private type declaration
13234 Partial_View := First_Entity (Current_Scope);
13236 exit when No (Partial_View)
13237 or else (Has_Private_Declaration (Partial_View)
13238 and then Full_View (Partial_View) = T);
13240 Next_Entity (Partial_View);
13243 -- If the partial view was not found then the source code has
13244 -- errors and the transformation is not needed.
13246 if Present (Partial_View) then
13247 Partial_View_Parent := Etype (Partial_View);
13249 -- If the parent of the full-view covers the parent of the
13250 -- partial-view we have nothing else to do.
13252 if Interface_Present_In_Ancestor
13253 (Parent_Type, Partial_View_Parent)
13257 -- Traverse the list of interfaces of the full-view to look
13258 -- for the parent of the partial-view and perform the tree
13262 Iface := First (Interface_List (Def));
13263 while Present (Iface) loop
13264 if Etype (Iface) = Etype (Partial_View) then
13265 Rewrite (Subtype_Indication (Def),
13266 New_Copy (Subtype_Indication
13267 (Parent (Partial_View))));
13269 New_Iface := Make_Identifier (Sloc (N),
13270 Chars (Parent_Type));
13271 Append (New_Iface, Interface_List (Def));
13273 -- Analyze the transformed code
13275 Derived_Type_Declaration (T, N, Is_Completion);
13286 -- Only composite types other than array types are allowed to have
13289 if Present (Discriminant_Specifications (N))
13290 and then (Is_Elementary_Type (Parent_Type)
13291 or else Is_Array_Type (Parent_Type))
13292 and then not Error_Posted (N)
13295 ("elementary or array type cannot have discriminants",
13296 Defining_Identifier (First (Discriminant_Specifications (N))));
13297 Set_Has_Discriminants (T, False);
13300 -- In Ada 83, a derived type defined in a package specification cannot
13301 -- be used for further derivation until the end of its visible part.
13302 -- Note that derivation in the private part of the package is allowed.
13304 if Ada_Version = Ada_83
13305 and then Is_Derived_Type (Parent_Type)
13306 and then In_Visible_Part (Scope (Parent_Type))
13308 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
13310 ("(Ada 83): premature use of type for derivation", Indic);
13314 -- Check for early use of incomplete or private type
13316 if Ekind (Parent_Type) = E_Void
13317 or else Ekind (Parent_Type) = E_Incomplete_Type
13319 Error_Msg_N ("premature derivation of incomplete type", Indic);
13322 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
13323 and then not Comes_From_Generic (Parent_Type))
13324 or else Has_Private_Component (Parent_Type)
13326 -- The ancestor type of a formal type can be incomplete, in which
13327 -- case only the operations of the partial view are available in
13328 -- the generic. Subsequent checks may be required when the full
13329 -- view is analyzed, to verify that derivation from a tagged type
13330 -- has an extension.
13332 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
13335 elsif No (Underlying_Type (Parent_Type))
13336 or else Has_Private_Component (Parent_Type)
13339 ("premature derivation of derived or private type", Indic);
13341 -- Flag the type itself as being in error, this prevents some
13342 -- nasty problems with subsequent uses of the malformed type.
13344 Set_Error_Posted (T);
13346 -- Check that within the immediate scope of an untagged partial
13347 -- view it's illegal to derive from the partial view if the
13348 -- full view is tagged. (7.3(7))
13350 -- We verify that the Parent_Type is a partial view by checking
13351 -- that it is not a Full_Type_Declaration (i.e. a private type or
13352 -- private extension declaration), to distinguish a partial view
13353 -- from a derivation from a private type which also appears as
13356 elsif Present (Full_View (Parent_Type))
13357 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
13358 and then not Is_Tagged_Type (Parent_Type)
13359 and then Is_Tagged_Type (Full_View (Parent_Type))
13361 Parent_Scope := Scope (T);
13362 while Present (Parent_Scope)
13363 and then Parent_Scope /= Standard_Standard
13365 if Parent_Scope = Scope (Parent_Type) then
13367 ("premature derivation from type with tagged full view",
13371 Parent_Scope := Scope (Parent_Scope);
13376 -- Check that form of derivation is appropriate
13378 Taggd := Is_Tagged_Type (Parent_Type);
13380 -- Perhaps the parent type should be changed to the class-wide type's
13381 -- specific type in this case to prevent cascading errors ???
13383 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
13384 Error_Msg_N ("parent type must not be a class-wide type", Indic);
13388 if Present (Extension) and then not Taggd then
13390 ("type derived from untagged type cannot have extension", Indic);
13392 elsif No (Extension) and then Taggd then
13394 -- If this declaration is within a private part (or body) of a
13395 -- generic instantiation then the derivation is allowed (the parent
13396 -- type can only appear tagged in this case if it's a generic actual
13397 -- type, since it would otherwise have been rejected in the analysis
13398 -- of the generic template).
13400 if not Is_Generic_Actual_Type (Parent_Type)
13401 or else In_Visible_Part (Scope (Parent_Type))
13404 ("type derived from tagged type must have extension", Indic);
13408 -- AI-443: Synchronized formal derived types require a private
13409 -- extension. There is no point in checking the ancestor type or
13410 -- the progenitors since the construct is wrong to begin with.
13412 if Ada_Version >= Ada_05
13413 and then Is_Generic_Type (T)
13414 and then Present (Original_Node (N))
13417 Decl : constant Node_Id := Original_Node (N);
13420 if Nkind (Decl) = N_Formal_Type_Declaration
13421 and then Nkind (Formal_Type_Definition (Decl)) =
13422 N_Formal_Derived_Type_Definition
13423 and then Synchronized_Present (Formal_Type_Definition (Decl))
13424 and then No (Extension)
13426 -- Avoid emitting a duplicate error message
13428 and then not Error_Posted (Indic)
13431 ("synchronized derived type must have extension", N);
13436 if Null_Exclusion_Present (Def)
13437 and then not Is_Access_Type (Parent_Type)
13439 Error_Msg_N ("null exclusion can only apply to an access type", N);
13442 -- Avoid deriving parent primitives of underlying record views
13444 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
13445 Derive_Subps => not Is_Underlying_Record_View (T));
13447 -- AI-419: The parent type of an explicitly limited derived type must
13448 -- be a limited type or a limited interface.
13450 if Limited_Present (Def) then
13451 Set_Is_Limited_Record (T);
13453 if Is_Interface (T) then
13454 Set_Is_Limited_Interface (T);
13457 if not Is_Limited_Type (Parent_Type)
13459 (not Is_Interface (Parent_Type)
13460 or else not Is_Limited_Interface (Parent_Type))
13462 Error_Msg_NE ("parent type& of limited type must be limited",
13466 end Derived_Type_Declaration;
13468 ------------------------
13469 -- Diagnose_Interface --
13470 ------------------------
13472 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
13474 if not Is_Interface (E)
13475 and then E /= Any_Type
13477 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
13479 end Diagnose_Interface;
13481 ----------------------------------
13482 -- Enumeration_Type_Declaration --
13483 ----------------------------------
13485 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
13492 -- Create identifier node representing lower bound
13494 B_Node := New_Node (N_Identifier, Sloc (Def));
13495 L := First (Literals (Def));
13496 Set_Chars (B_Node, Chars (L));
13497 Set_Entity (B_Node, L);
13498 Set_Etype (B_Node, T);
13499 Set_Is_Static_Expression (B_Node, True);
13501 R_Node := New_Node (N_Range, Sloc (Def));
13502 Set_Low_Bound (R_Node, B_Node);
13504 Set_Ekind (T, E_Enumeration_Type);
13505 Set_First_Literal (T, L);
13507 Set_Is_Constrained (T);
13511 -- Loop through literals of enumeration type setting pos and rep values
13512 -- except that if the Ekind is already set, then it means the literal
13513 -- was already constructed (case of a derived type declaration and we
13514 -- should not disturb the Pos and Rep values.
13516 while Present (L) loop
13517 if Ekind (L) /= E_Enumeration_Literal then
13518 Set_Ekind (L, E_Enumeration_Literal);
13519 Set_Enumeration_Pos (L, Ev);
13520 Set_Enumeration_Rep (L, Ev);
13521 Set_Is_Known_Valid (L, True);
13525 New_Overloaded_Entity (L);
13526 Generate_Definition (L);
13527 Set_Convention (L, Convention_Intrinsic);
13529 if Nkind (L) = N_Defining_Character_Literal then
13530 Set_Is_Character_Type (T, True);
13537 -- Now create a node representing upper bound
13539 B_Node := New_Node (N_Identifier, Sloc (Def));
13540 Set_Chars (B_Node, Chars (Last (Literals (Def))));
13541 Set_Entity (B_Node, Last (Literals (Def)));
13542 Set_Etype (B_Node, T);
13543 Set_Is_Static_Expression (B_Node, True);
13545 Set_High_Bound (R_Node, B_Node);
13547 -- Initialize various fields of the type. Some of this information
13548 -- may be overwritten later through rep.clauses.
13550 Set_Scalar_Range (T, R_Node);
13551 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
13552 Set_Enum_Esize (T);
13553 Set_Enum_Pos_To_Rep (T, Empty);
13555 -- Set Discard_Names if configuration pragma set, or if there is
13556 -- a parameterless pragma in the current declarative region
13558 if Global_Discard_Names
13559 or else Discard_Names (Scope (T))
13561 Set_Discard_Names (T);
13564 -- Process end label if there is one
13566 if Present (Def) then
13567 Process_End_Label (Def, 'e', T);
13569 end Enumeration_Type_Declaration;
13571 ---------------------------------
13572 -- Expand_To_Stored_Constraint --
13573 ---------------------------------
13575 function Expand_To_Stored_Constraint
13577 Constraint : Elist_Id) return Elist_Id
13579 Explicitly_Discriminated_Type : Entity_Id;
13580 Expansion : Elist_Id;
13581 Discriminant : Entity_Id;
13583 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
13584 -- Find the nearest type that actually specifies discriminants
13586 ---------------------------------
13587 -- Type_With_Explicit_Discrims --
13588 ---------------------------------
13590 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
13591 Typ : constant E := Base_Type (Id);
13594 if Ekind (Typ) in Incomplete_Or_Private_Kind then
13595 if Present (Full_View (Typ)) then
13596 return Type_With_Explicit_Discrims (Full_View (Typ));
13600 if Has_Discriminants (Typ) then
13605 if Etype (Typ) = Typ then
13607 elsif Has_Discriminants (Typ) then
13610 return Type_With_Explicit_Discrims (Etype (Typ));
13613 end Type_With_Explicit_Discrims;
13615 -- Start of processing for Expand_To_Stored_Constraint
13619 or else Is_Empty_Elmt_List (Constraint)
13624 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
13626 if No (Explicitly_Discriminated_Type) then
13630 Expansion := New_Elmt_List;
13633 First_Stored_Discriminant (Explicitly_Discriminated_Type);
13634 while Present (Discriminant) loop
13636 Get_Discriminant_Value (
13637 Discriminant, Explicitly_Discriminated_Type, Constraint),
13639 Next_Stored_Discriminant (Discriminant);
13643 end Expand_To_Stored_Constraint;
13645 ---------------------------
13646 -- Find_Hidden_Interface --
13647 ---------------------------
13649 function Find_Hidden_Interface
13651 Dest : Elist_Id) return Entity_Id
13654 Iface_Elmt : Elmt_Id;
13657 if Present (Src) and then Present (Dest) then
13658 Iface_Elmt := First_Elmt (Src);
13659 while Present (Iface_Elmt) loop
13660 Iface := Node (Iface_Elmt);
13662 if Is_Interface (Iface)
13663 and then not Contain_Interface (Iface, Dest)
13668 Next_Elmt (Iface_Elmt);
13673 end Find_Hidden_Interface;
13675 --------------------
13676 -- Find_Type_Name --
13677 --------------------
13679 function Find_Type_Name (N : Node_Id) return Entity_Id is
13680 Id : constant Entity_Id := Defining_Identifier (N);
13682 New_Id : Entity_Id;
13683 Prev_Par : Node_Id;
13685 procedure Tag_Mismatch;
13686 -- Diagnose a tagged partial view whose full view is untagged.
13687 -- We post the message on the full view, with a reference to
13688 -- the previous partial view. The partial view can be private
13689 -- or incomplete, and these are handled in a different manner,
13690 -- so we determine the position of the error message from the
13691 -- respective slocs of both.
13697 procedure Tag_Mismatch is
13699 if Sloc (Prev) < Sloc (Id) then
13701 ("full declaration of } must be a tagged type ", Id, Prev);
13704 ("full declaration of } must be a tagged type ", Prev, Id);
13708 -- Start of processing for Find_Type_Name
13711 -- Find incomplete declaration, if one was given
13713 Prev := Current_Entity_In_Scope (Id);
13715 if Present (Prev) then
13717 -- Previous declaration exists. Error if not incomplete/private case
13718 -- except if previous declaration is implicit, etc. Enter_Name will
13719 -- emit error if appropriate.
13721 Prev_Par := Parent (Prev);
13723 if not Is_Incomplete_Or_Private_Type (Prev) then
13727 elsif not Nkind_In (N, N_Full_Type_Declaration,
13728 N_Task_Type_Declaration,
13729 N_Protected_Type_Declaration)
13731 -- Completion must be a full type declarations (RM 7.3(4))
13733 Error_Msg_Sloc := Sloc (Prev);
13734 Error_Msg_NE ("invalid completion of }", Id, Prev);
13736 -- Set scope of Id to avoid cascaded errors. Entity is never
13737 -- examined again, except when saving globals in generics.
13739 Set_Scope (Id, Current_Scope);
13742 -- If this is a repeated incomplete declaration, no further
13743 -- checks are possible.
13745 if Nkind (N) = N_Incomplete_Type_Declaration then
13749 -- Case of full declaration of incomplete type
13751 elsif Ekind (Prev) = E_Incomplete_Type then
13753 -- Indicate that the incomplete declaration has a matching full
13754 -- declaration. The defining occurrence of the incomplete
13755 -- declaration remains the visible one, and the procedure
13756 -- Get_Full_View dereferences it whenever the type is used.
13758 if Present (Full_View (Prev)) then
13759 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
13762 Set_Full_View (Prev, Id);
13763 Append_Entity (Id, Current_Scope);
13764 Set_Is_Public (Id, Is_Public (Prev));
13765 Set_Is_Internal (Id);
13768 -- Case of full declaration of private type
13771 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
13772 if Etype (Prev) /= Prev then
13774 -- Prev is a private subtype or a derived type, and needs
13777 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
13780 elsif Ekind (Prev) = E_Private_Type
13781 and then Nkind_In (N, N_Task_Type_Declaration,
13782 N_Protected_Type_Declaration)
13785 ("completion of nonlimited type cannot be limited", N);
13787 elsif Ekind (Prev) = E_Record_Type_With_Private
13788 and then Nkind_In (N, N_Task_Type_Declaration,
13789 N_Protected_Type_Declaration)
13791 if not Is_Limited_Record (Prev) then
13793 ("completion of nonlimited type cannot be limited", N);
13795 elsif No (Interface_List (N)) then
13797 ("completion of tagged private type must be tagged",
13801 elsif Nkind (N) = N_Full_Type_Declaration
13803 Nkind (Type_Definition (N)) = N_Record_Definition
13804 and then Interface_Present (Type_Definition (N))
13807 ("completion of private type cannot be an interface", N);
13810 -- Ada 2005 (AI-251): Private extension declaration of a task
13811 -- type or a protected type. This case arises when covering
13812 -- interface types.
13814 elsif Nkind_In (N, N_Task_Type_Declaration,
13815 N_Protected_Type_Declaration)
13819 elsif Nkind (N) /= N_Full_Type_Declaration
13820 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
13823 ("full view of private extension must be an extension", N);
13825 elsif not (Abstract_Present (Parent (Prev)))
13826 and then Abstract_Present (Type_Definition (N))
13829 ("full view of non-abstract extension cannot be abstract", N);
13832 if not In_Private_Part (Current_Scope) then
13834 ("declaration of full view must appear in private part", N);
13837 Copy_And_Swap (Prev, Id);
13838 Set_Has_Private_Declaration (Prev);
13839 Set_Has_Private_Declaration (Id);
13841 -- If no error, propagate freeze_node from private to full view.
13842 -- It may have been generated for an early operational item.
13844 if Present (Freeze_Node (Id))
13845 and then Serious_Errors_Detected = 0
13846 and then No (Full_View (Id))
13848 Set_Freeze_Node (Prev, Freeze_Node (Id));
13849 Set_Freeze_Node (Id, Empty);
13850 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
13853 Set_Full_View (Id, Prev);
13857 -- Verify that full declaration conforms to partial one
13859 if Is_Incomplete_Or_Private_Type (Prev)
13860 and then Present (Discriminant_Specifications (Prev_Par))
13862 if Present (Discriminant_Specifications (N)) then
13863 if Ekind (Prev) = E_Incomplete_Type then
13864 Check_Discriminant_Conformance (N, Prev, Prev);
13866 Check_Discriminant_Conformance (N, Prev, Id);
13871 ("missing discriminants in full type declaration", N);
13873 -- To avoid cascaded errors on subsequent use, share the
13874 -- discriminants of the partial view.
13876 Set_Discriminant_Specifications (N,
13877 Discriminant_Specifications (Prev_Par));
13881 -- A prior untagged partial view can have an associated class-wide
13882 -- type due to use of the class attribute, and in this case the full
13883 -- type must also be tagged. This Ada 95 usage is deprecated in favor
13884 -- of incomplete tagged declarations, but we check for it.
13887 and then (Is_Tagged_Type (Prev)
13888 or else Present (Class_Wide_Type (Prev)))
13890 -- The full declaration is either a tagged type (including
13891 -- a synchronized type that implements interfaces) or a
13892 -- type extension, otherwise this is an error.
13894 if Nkind_In (N, N_Task_Type_Declaration,
13895 N_Protected_Type_Declaration)
13897 if No (Interface_List (N))
13898 and then not Error_Posted (N)
13903 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
13905 -- Indicate that the previous declaration (tagged incomplete
13906 -- or private declaration) requires the same on the full one.
13908 if not Tagged_Present (Type_Definition (N)) then
13910 Set_Is_Tagged_Type (Id);
13911 Set_Primitive_Operations (Id, New_Elmt_List);
13914 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
13915 if No (Record_Extension_Part (Type_Definition (N))) then
13917 "full declaration of } must be a record extension",
13920 -- Set some attributes to produce a usable full view
13922 Set_Is_Tagged_Type (Id);
13923 Set_Primitive_Operations (Id, New_Elmt_List);
13934 -- New type declaration
13939 end Find_Type_Name;
13941 -------------------------
13942 -- Find_Type_Of_Object --
13943 -------------------------
13945 function Find_Type_Of_Object
13946 (Obj_Def : Node_Id;
13947 Related_Nod : Node_Id) return Entity_Id
13949 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
13950 P : Node_Id := Parent (Obj_Def);
13955 -- If the parent is a component_definition node we climb to the
13956 -- component_declaration node
13958 if Nkind (P) = N_Component_Definition then
13962 -- Case of an anonymous array subtype
13964 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
13965 N_Unconstrained_Array_Definition)
13968 Array_Type_Declaration (T, Obj_Def);
13970 -- Create an explicit subtype whenever possible
13972 elsif Nkind (P) /= N_Component_Declaration
13973 and then Def_Kind = N_Subtype_Indication
13975 -- Base name of subtype on object name, which will be unique in
13976 -- the current scope.
13978 -- If this is a duplicate declaration, return base type, to avoid
13979 -- generating duplicate anonymous types.
13981 if Error_Posted (P) then
13982 Analyze (Subtype_Mark (Obj_Def));
13983 return Entity (Subtype_Mark (Obj_Def));
13988 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
13990 T := Make_Defining_Identifier (Sloc (P), Nam);
13992 Insert_Action (Obj_Def,
13993 Make_Subtype_Declaration (Sloc (P),
13994 Defining_Identifier => T,
13995 Subtype_Indication => Relocate_Node (Obj_Def)));
13997 -- This subtype may need freezing, and this will not be done
13998 -- automatically if the object declaration is not in declarative
13999 -- part. Since this is an object declaration, the type cannot always
14000 -- be frozen here. Deferred constants do not freeze their type
14001 -- (which often enough will be private).
14003 if Nkind (P) = N_Object_Declaration
14004 and then Constant_Present (P)
14005 and then No (Expression (P))
14009 Insert_Actions (Obj_Def, Freeze_Entity (T, Sloc (P)));
14012 -- Ada 2005 AI-406: the object definition in an object declaration
14013 -- can be an access definition.
14015 elsif Def_Kind = N_Access_Definition then
14016 T := Access_Definition (Related_Nod, Obj_Def);
14017 Set_Is_Local_Anonymous_Access (T);
14019 -- Otherwise, the object definition is just a subtype_mark
14022 T := Process_Subtype (Obj_Def, Related_Nod);
14026 end Find_Type_Of_Object;
14028 --------------------------------
14029 -- Find_Type_Of_Subtype_Indic --
14030 --------------------------------
14032 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
14036 -- Case of subtype mark with a constraint
14038 if Nkind (S) = N_Subtype_Indication then
14039 Find_Type (Subtype_Mark (S));
14040 Typ := Entity (Subtype_Mark (S));
14043 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
14046 ("incorrect constraint for this kind of type", Constraint (S));
14047 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
14050 -- Otherwise we have a subtype mark without a constraint
14052 elsif Error_Posted (S) then
14053 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
14061 -- Check No_Wide_Characters restriction
14063 if Typ = Standard_Wide_Character
14064 or else Typ = Standard_Wide_Wide_Character
14065 or else Typ = Standard_Wide_String
14066 or else Typ = Standard_Wide_Wide_String
14068 Check_Restriction (No_Wide_Characters, S);
14072 end Find_Type_Of_Subtype_Indic;
14074 -------------------------------------
14075 -- Floating_Point_Type_Declaration --
14076 -------------------------------------
14078 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
14079 Digs : constant Node_Id := Digits_Expression (Def);
14081 Base_Typ : Entity_Id;
14082 Implicit_Base : Entity_Id;
14085 function Can_Derive_From (E : Entity_Id) return Boolean;
14086 -- Find if given digits value allows derivation from specified type
14088 ---------------------
14089 -- Can_Derive_From --
14090 ---------------------
14092 function Can_Derive_From (E : Entity_Id) return Boolean is
14093 Spec : constant Entity_Id := Real_Range_Specification (Def);
14096 if Digs_Val > Digits_Value (E) then
14100 if Present (Spec) then
14101 if Expr_Value_R (Type_Low_Bound (E)) >
14102 Expr_Value_R (Low_Bound (Spec))
14107 if Expr_Value_R (Type_High_Bound (E)) <
14108 Expr_Value_R (High_Bound (Spec))
14115 end Can_Derive_From;
14117 -- Start of processing for Floating_Point_Type_Declaration
14120 Check_Restriction (No_Floating_Point, Def);
14122 -- Create an implicit base type
14125 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
14127 -- Analyze and verify digits value
14129 Analyze_And_Resolve (Digs, Any_Integer);
14130 Check_Digits_Expression (Digs);
14131 Digs_Val := Expr_Value (Digs);
14133 -- Process possible range spec and find correct type to derive from
14135 Process_Real_Range_Specification (Def);
14137 if Can_Derive_From (Standard_Short_Float) then
14138 Base_Typ := Standard_Short_Float;
14139 elsif Can_Derive_From (Standard_Float) then
14140 Base_Typ := Standard_Float;
14141 elsif Can_Derive_From (Standard_Long_Float) then
14142 Base_Typ := Standard_Long_Float;
14143 elsif Can_Derive_From (Standard_Long_Long_Float) then
14144 Base_Typ := Standard_Long_Long_Float;
14146 -- If we can't derive from any existing type, use long_long_float
14147 -- and give appropriate message explaining the problem.
14150 Base_Typ := Standard_Long_Long_Float;
14152 if Digs_Val >= Digits_Value (Standard_Long_Long_Float) then
14153 Error_Msg_Uint_1 := Digits_Value (Standard_Long_Long_Float);
14154 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
14158 ("range too large for any predefined type",
14159 Real_Range_Specification (Def));
14163 -- If there are bounds given in the declaration use them as the bounds
14164 -- of the type, otherwise use the bounds of the predefined base type
14165 -- that was chosen based on the Digits value.
14167 if Present (Real_Range_Specification (Def)) then
14168 Set_Scalar_Range (T, Real_Range_Specification (Def));
14169 Set_Is_Constrained (T);
14171 -- The bounds of this range must be converted to machine numbers
14172 -- in accordance with RM 4.9(38).
14174 Bound := Type_Low_Bound (T);
14176 if Nkind (Bound) = N_Real_Literal then
14178 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
14179 Set_Is_Machine_Number (Bound);
14182 Bound := Type_High_Bound (T);
14184 if Nkind (Bound) = N_Real_Literal then
14186 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
14187 Set_Is_Machine_Number (Bound);
14191 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
14194 -- Complete definition of implicit base and declared first subtype
14196 Set_Etype (Implicit_Base, Base_Typ);
14198 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
14199 Set_Size_Info (Implicit_Base, (Base_Typ));
14200 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
14201 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
14202 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
14203 Set_Vax_Float (Implicit_Base, Vax_Float (Base_Typ));
14205 Set_Ekind (T, E_Floating_Point_Subtype);
14206 Set_Etype (T, Implicit_Base);
14208 Set_Size_Info (T, (Implicit_Base));
14209 Set_RM_Size (T, RM_Size (Implicit_Base));
14210 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
14211 Set_Digits_Value (T, Digs_Val);
14212 end Floating_Point_Type_Declaration;
14214 ----------------------------
14215 -- Get_Discriminant_Value --
14216 ----------------------------
14218 -- This is the situation:
14220 -- There is a non-derived type
14222 -- type T0 (Dx, Dy, Dz...)
14224 -- There are zero or more levels of derivation, with each derivation
14225 -- either purely inheriting the discriminants, or defining its own.
14227 -- type Ti is new Ti-1
14229 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
14231 -- subtype Ti is ...
14233 -- The subtype issue is avoided by the use of Original_Record_Component,
14234 -- and the fact that derived subtypes also derive the constraints.
14236 -- This chain leads back from
14238 -- Typ_For_Constraint
14240 -- Typ_For_Constraint has discriminants, and the value for each
14241 -- discriminant is given by its corresponding Elmt of Constraints.
14243 -- Discriminant is some discriminant in this hierarchy
14245 -- We need to return its value
14247 -- We do this by recursively searching each level, and looking for
14248 -- Discriminant. Once we get to the bottom, we start backing up
14249 -- returning the value for it which may in turn be a discriminant
14250 -- further up, so on the backup we continue the substitution.
14252 function Get_Discriminant_Value
14253 (Discriminant : Entity_Id;
14254 Typ_For_Constraint : Entity_Id;
14255 Constraint : Elist_Id) return Node_Id
14257 function Search_Derivation_Levels
14259 Discrim_Values : Elist_Id;
14260 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
14261 -- This is the routine that performs the recursive search of levels
14262 -- as described above.
14264 ------------------------------
14265 -- Search_Derivation_Levels --
14266 ------------------------------
14268 function Search_Derivation_Levels
14270 Discrim_Values : Elist_Id;
14271 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
14275 Result : Node_Or_Entity_Id;
14276 Result_Entity : Node_Id;
14279 -- If inappropriate type, return Error, this happens only in
14280 -- cascaded error situations, and we want to avoid a blow up.
14282 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
14286 -- Look deeper if possible. Use Stored_Constraints only for
14287 -- untagged types. For tagged types use the given constraint.
14288 -- This asymmetry needs explanation???
14290 if not Stored_Discrim_Values
14291 and then Present (Stored_Constraint (Ti))
14292 and then not Is_Tagged_Type (Ti)
14295 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
14298 Td : constant Entity_Id := Etype (Ti);
14302 Result := Discriminant;
14305 if Present (Stored_Constraint (Ti)) then
14307 Search_Derivation_Levels
14308 (Td, Stored_Constraint (Ti), True);
14311 Search_Derivation_Levels
14312 (Td, Discrim_Values, Stored_Discrim_Values);
14318 -- Extra underlying places to search, if not found above. For
14319 -- concurrent types, the relevant discriminant appears in the
14320 -- corresponding record. For a type derived from a private type
14321 -- without discriminant, the full view inherits the discriminants
14322 -- of the full view of the parent.
14324 if Result = Discriminant then
14325 if Is_Concurrent_Type (Ti)
14326 and then Present (Corresponding_Record_Type (Ti))
14329 Search_Derivation_Levels (
14330 Corresponding_Record_Type (Ti),
14332 Stored_Discrim_Values);
14334 elsif Is_Private_Type (Ti)
14335 and then not Has_Discriminants (Ti)
14336 and then Present (Full_View (Ti))
14337 and then Etype (Full_View (Ti)) /= Ti
14340 Search_Derivation_Levels (
14343 Stored_Discrim_Values);
14347 -- If Result is not a (reference to a) discriminant, return it,
14348 -- otherwise set Result_Entity to the discriminant.
14350 if Nkind (Result) = N_Defining_Identifier then
14351 pragma Assert (Result = Discriminant);
14352 Result_Entity := Result;
14355 if not Denotes_Discriminant (Result) then
14359 Result_Entity := Entity (Result);
14362 -- See if this level of derivation actually has discriminants
14363 -- because tagged derivations can add them, hence the lower
14364 -- levels need not have any.
14366 if not Has_Discriminants (Ti) then
14370 -- Scan Ti's discriminants for Result_Entity,
14371 -- and return its corresponding value, if any.
14373 Result_Entity := Original_Record_Component (Result_Entity);
14375 Assoc := First_Elmt (Discrim_Values);
14377 if Stored_Discrim_Values then
14378 Disc := First_Stored_Discriminant (Ti);
14380 Disc := First_Discriminant (Ti);
14383 while Present (Disc) loop
14384 pragma Assert (Present (Assoc));
14386 if Original_Record_Component (Disc) = Result_Entity then
14387 return Node (Assoc);
14392 if Stored_Discrim_Values then
14393 Next_Stored_Discriminant (Disc);
14395 Next_Discriminant (Disc);
14399 -- Could not find it
14402 end Search_Derivation_Levels;
14406 Result : Node_Or_Entity_Id;
14408 -- Start of processing for Get_Discriminant_Value
14411 -- ??? This routine is a gigantic mess and will be deleted. For the
14412 -- time being just test for the trivial case before calling recurse.
14414 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
14420 D := First_Discriminant (Typ_For_Constraint);
14421 E := First_Elmt (Constraint);
14422 while Present (D) loop
14423 if Chars (D) = Chars (Discriminant) then
14427 Next_Discriminant (D);
14433 Result := Search_Derivation_Levels
14434 (Typ_For_Constraint, Constraint, False);
14436 -- ??? hack to disappear when this routine is gone
14438 if Nkind (Result) = N_Defining_Identifier then
14444 D := First_Discriminant (Typ_For_Constraint);
14445 E := First_Elmt (Constraint);
14446 while Present (D) loop
14447 if Corresponding_Discriminant (D) = Discriminant then
14451 Next_Discriminant (D);
14457 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
14459 end Get_Discriminant_Value;
14461 --------------------------
14462 -- Has_Range_Constraint --
14463 --------------------------
14465 function Has_Range_Constraint (N : Node_Id) return Boolean is
14466 C : constant Node_Id := Constraint (N);
14469 if Nkind (C) = N_Range_Constraint then
14472 elsif Nkind (C) = N_Digits_Constraint then
14474 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
14476 Present (Range_Constraint (C));
14478 elsif Nkind (C) = N_Delta_Constraint then
14479 return Present (Range_Constraint (C));
14484 end Has_Range_Constraint;
14486 ------------------------
14487 -- Inherit_Components --
14488 ------------------------
14490 function Inherit_Components
14492 Parent_Base : Entity_Id;
14493 Derived_Base : Entity_Id;
14494 Is_Tagged : Boolean;
14495 Inherit_Discr : Boolean;
14496 Discs : Elist_Id) return Elist_Id
14498 Assoc_List : constant Elist_Id := New_Elmt_List;
14500 procedure Inherit_Component
14501 (Old_C : Entity_Id;
14502 Plain_Discrim : Boolean := False;
14503 Stored_Discrim : Boolean := False);
14504 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
14505 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
14506 -- True, Old_C is a stored discriminant. If they are both false then
14507 -- Old_C is a regular component.
14509 -----------------------
14510 -- Inherit_Component --
14511 -----------------------
14513 procedure Inherit_Component
14514 (Old_C : Entity_Id;
14515 Plain_Discrim : Boolean := False;
14516 Stored_Discrim : Boolean := False)
14518 New_C : constant Entity_Id := New_Copy (Old_C);
14520 Discrim : Entity_Id;
14521 Corr_Discrim : Entity_Id;
14524 pragma Assert (not Is_Tagged or else not Stored_Discrim);
14526 Set_Parent (New_C, Parent (Old_C));
14528 -- Regular discriminants and components must be inserted in the scope
14529 -- of the Derived_Base. Do it here.
14531 if not Stored_Discrim then
14532 Enter_Name (New_C);
14535 -- For tagged types the Original_Record_Component must point to
14536 -- whatever this field was pointing to in the parent type. This has
14537 -- already been achieved by the call to New_Copy above.
14539 if not Is_Tagged then
14540 Set_Original_Record_Component (New_C, New_C);
14543 -- If we have inherited a component then see if its Etype contains
14544 -- references to Parent_Base discriminants. In this case, replace
14545 -- these references with the constraints given in Discs. We do not
14546 -- do this for the partial view of private types because this is
14547 -- not needed (only the components of the full view will be used
14548 -- for code generation) and cause problem. We also avoid this
14549 -- transformation in some error situations.
14551 if Ekind (New_C) = E_Component then
14552 if (Is_Private_Type (Derived_Base)
14553 and then not Is_Generic_Type (Derived_Base))
14554 or else (Is_Empty_Elmt_List (Discs)
14555 and then not Expander_Active)
14557 Set_Etype (New_C, Etype (Old_C));
14560 -- The current component introduces a circularity of the
14563 -- limited with Pack_2;
14564 -- package Pack_1 is
14565 -- type T_1 is tagged record
14566 -- Comp : access Pack_2.T_2;
14572 -- package Pack_2 is
14573 -- type T_2 is new Pack_1.T_1 with ...;
14578 Constrain_Component_Type
14579 (Old_C, Derived_Base, N, Parent_Base, Discs));
14583 -- In derived tagged types it is illegal to reference a non
14584 -- discriminant component in the parent type. To catch this, mark
14585 -- these components with an Ekind of E_Void. This will be reset in
14586 -- Record_Type_Definition after processing the record extension of
14587 -- the derived type.
14589 -- If the declaration is a private extension, there is no further
14590 -- record extension to process, and the components retain their
14591 -- current kind, because they are visible at this point.
14593 if Is_Tagged and then Ekind (New_C) = E_Component
14594 and then Nkind (N) /= N_Private_Extension_Declaration
14596 Set_Ekind (New_C, E_Void);
14599 if Plain_Discrim then
14600 Set_Corresponding_Discriminant (New_C, Old_C);
14601 Build_Discriminal (New_C);
14603 -- If we are explicitly inheriting a stored discriminant it will be
14604 -- completely hidden.
14606 elsif Stored_Discrim then
14607 Set_Corresponding_Discriminant (New_C, Empty);
14608 Set_Discriminal (New_C, Empty);
14609 Set_Is_Completely_Hidden (New_C);
14611 -- Set the Original_Record_Component of each discriminant in the
14612 -- derived base to point to the corresponding stored that we just
14615 Discrim := First_Discriminant (Derived_Base);
14616 while Present (Discrim) loop
14617 Corr_Discrim := Corresponding_Discriminant (Discrim);
14619 -- Corr_Discrim could be missing in an error situation
14621 if Present (Corr_Discrim)
14622 and then Original_Record_Component (Corr_Discrim) = Old_C
14624 Set_Original_Record_Component (Discrim, New_C);
14627 Next_Discriminant (Discrim);
14630 Append_Entity (New_C, Derived_Base);
14633 if not Is_Tagged then
14634 Append_Elmt (Old_C, Assoc_List);
14635 Append_Elmt (New_C, Assoc_List);
14637 end Inherit_Component;
14639 -- Variables local to Inherit_Component
14641 Loc : constant Source_Ptr := Sloc (N);
14643 Parent_Discrim : Entity_Id;
14644 Stored_Discrim : Entity_Id;
14646 Component : Entity_Id;
14648 -- Start of processing for Inherit_Components
14651 if not Is_Tagged then
14652 Append_Elmt (Parent_Base, Assoc_List);
14653 Append_Elmt (Derived_Base, Assoc_List);
14656 -- Inherit parent discriminants if needed
14658 if Inherit_Discr then
14659 Parent_Discrim := First_Discriminant (Parent_Base);
14660 while Present (Parent_Discrim) loop
14661 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
14662 Next_Discriminant (Parent_Discrim);
14666 -- Create explicit stored discrims for untagged types when necessary
14668 if not Has_Unknown_Discriminants (Derived_Base)
14669 and then Has_Discriminants (Parent_Base)
14670 and then not Is_Tagged
14673 or else First_Discriminant (Parent_Base) /=
14674 First_Stored_Discriminant (Parent_Base))
14676 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
14677 while Present (Stored_Discrim) loop
14678 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
14679 Next_Stored_Discriminant (Stored_Discrim);
14683 -- See if we can apply the second transformation for derived types, as
14684 -- explained in point 6. in the comments above Build_Derived_Record_Type
14685 -- This is achieved by appending Derived_Base discriminants into Discs,
14686 -- which has the side effect of returning a non empty Discs list to the
14687 -- caller of Inherit_Components, which is what we want. This must be
14688 -- done for private derived types if there are explicit stored
14689 -- discriminants, to ensure that we can retrieve the values of the
14690 -- constraints provided in the ancestors.
14693 and then Is_Empty_Elmt_List (Discs)
14694 and then Present (First_Discriminant (Derived_Base))
14696 (not Is_Private_Type (Derived_Base)
14697 or else Is_Completely_Hidden
14698 (First_Stored_Discriminant (Derived_Base))
14699 or else Is_Generic_Type (Derived_Base))
14701 D := First_Discriminant (Derived_Base);
14702 while Present (D) loop
14703 Append_Elmt (New_Reference_To (D, Loc), Discs);
14704 Next_Discriminant (D);
14708 -- Finally, inherit non-discriminant components unless they are not
14709 -- visible because defined or inherited from the full view of the
14710 -- parent. Don't inherit the _parent field of the parent type.
14712 Component := First_Entity (Parent_Base);
14713 while Present (Component) loop
14715 -- Ada 2005 (AI-251): Do not inherit components associated with
14716 -- secondary tags of the parent.
14718 if Ekind (Component) = E_Component
14719 and then Present (Related_Type (Component))
14723 elsif Ekind (Component) /= E_Component
14724 or else Chars (Component) = Name_uParent
14728 -- If the derived type is within the parent type's declarative
14729 -- region, then the components can still be inherited even though
14730 -- they aren't visible at this point. This can occur for cases
14731 -- such as within public child units where the components must
14732 -- become visible upon entering the child unit's private part.
14734 elsif not Is_Visible_Component (Component)
14735 and then not In_Open_Scopes (Scope (Parent_Base))
14739 elsif Ekind (Derived_Base) = E_Private_Type
14740 or else Ekind (Derived_Base) = E_Limited_Private_Type
14745 Inherit_Component (Component);
14748 Next_Entity (Component);
14751 -- For tagged derived types, inherited discriminants cannot be used in
14752 -- component declarations of the record extension part. To achieve this
14753 -- we mark the inherited discriminants as not visible.
14755 if Is_Tagged and then Inherit_Discr then
14756 D := First_Discriminant (Derived_Base);
14757 while Present (D) loop
14758 Set_Is_Immediately_Visible (D, False);
14759 Next_Discriminant (D);
14764 end Inherit_Components;
14766 -----------------------
14767 -- Is_Null_Extension --
14768 -----------------------
14770 function Is_Null_Extension (T : Entity_Id) return Boolean is
14771 Type_Decl : constant Node_Id := Parent (Base_Type (T));
14772 Comp_List : Node_Id;
14776 if Nkind (Type_Decl) /= N_Full_Type_Declaration
14777 or else not Is_Tagged_Type (T)
14778 or else Nkind (Type_Definition (Type_Decl)) /=
14779 N_Derived_Type_Definition
14780 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
14786 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
14788 if Present (Discriminant_Specifications (Type_Decl)) then
14791 elsif Present (Comp_List)
14792 and then Is_Non_Empty_List (Component_Items (Comp_List))
14794 Comp := First (Component_Items (Comp_List));
14796 -- Only user-defined components are relevant. The component list
14797 -- may also contain a parent component and internal components
14798 -- corresponding to secondary tags, but these do not determine
14799 -- whether this is a null extension.
14801 while Present (Comp) loop
14802 if Comes_From_Source (Comp) then
14813 end Is_Null_Extension;
14815 --------------------
14816 -- Is_Progenitor --
14817 --------------------
14819 function Is_Progenitor
14820 (Iface : Entity_Id;
14821 Typ : Entity_Id) return Boolean
14824 return Implements_Interface (Typ, Iface,
14825 Exclude_Parents => True);
14828 ------------------------------
14829 -- Is_Valid_Constraint_Kind --
14830 ------------------------------
14832 function Is_Valid_Constraint_Kind
14833 (T_Kind : Type_Kind;
14834 Constraint_Kind : Node_Kind) return Boolean
14838 when Enumeration_Kind |
14840 return Constraint_Kind = N_Range_Constraint;
14842 when Decimal_Fixed_Point_Kind =>
14843 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
14844 N_Range_Constraint);
14846 when Ordinary_Fixed_Point_Kind =>
14847 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
14848 N_Range_Constraint);
14851 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
14852 N_Range_Constraint);
14859 E_Incomplete_Type |
14862 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
14865 return True; -- Error will be detected later
14867 end Is_Valid_Constraint_Kind;
14869 --------------------------
14870 -- Is_Visible_Component --
14871 --------------------------
14873 function Is_Visible_Component (C : Entity_Id) return Boolean is
14874 Original_Comp : Entity_Id := Empty;
14875 Original_Scope : Entity_Id;
14876 Type_Scope : Entity_Id;
14878 function Is_Local_Type (Typ : Entity_Id) return Boolean;
14879 -- Check whether parent type of inherited component is declared locally,
14880 -- possibly within a nested package or instance. The current scope is
14881 -- the derived record itself.
14883 -------------------
14884 -- Is_Local_Type --
14885 -------------------
14887 function Is_Local_Type (Typ : Entity_Id) return Boolean is
14891 Scop := Scope (Typ);
14892 while Present (Scop)
14893 and then Scop /= Standard_Standard
14895 if Scop = Scope (Current_Scope) then
14899 Scop := Scope (Scop);
14905 -- Start of processing for Is_Visible_Component
14908 if Ekind (C) = E_Component
14909 or else Ekind (C) = E_Discriminant
14911 Original_Comp := Original_Record_Component (C);
14914 if No (Original_Comp) then
14916 -- Premature usage, or previous error
14921 Original_Scope := Scope (Original_Comp);
14922 Type_Scope := Scope (Base_Type (Scope (C)));
14925 -- This test only concerns tagged types
14927 if not Is_Tagged_Type (Original_Scope) then
14930 -- If it is _Parent or _Tag, there is no visibility issue
14932 elsif not Comes_From_Source (Original_Comp) then
14935 -- If we are in the body of an instantiation, the component is visible
14936 -- even when the parent type (possibly defined in an enclosing unit or
14937 -- in a parent unit) might not.
14939 elsif In_Instance_Body then
14942 -- Discriminants are always visible
14944 elsif Ekind (Original_Comp) = E_Discriminant
14945 and then not Has_Unknown_Discriminants (Original_Scope)
14949 -- If the component has been declared in an ancestor which is currently
14950 -- a private type, then it is not visible. The same applies if the
14951 -- component's containing type is not in an open scope and the original
14952 -- component's enclosing type is a visible full view of a private type
14953 -- (which can occur in cases where an attempt is being made to reference
14954 -- a component in a sibling package that is inherited from a visible
14955 -- component of a type in an ancestor package; the component in the
14956 -- sibling package should not be visible even though the component it
14957 -- inherited from is visible). This does not apply however in the case
14958 -- where the scope of the type is a private child unit, or when the
14959 -- parent comes from a local package in which the ancestor is currently
14960 -- visible. The latter suppression of visibility is needed for cases
14961 -- that are tested in B730006.
14963 elsif Is_Private_Type (Original_Scope)
14965 (not Is_Private_Descendant (Type_Scope)
14966 and then not In_Open_Scopes (Type_Scope)
14967 and then Has_Private_Declaration (Original_Scope))
14969 -- If the type derives from an entity in a formal package, there
14970 -- are no additional visible components.
14972 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
14973 N_Formal_Package_Declaration
14977 -- if we are not in the private part of the current package, there
14978 -- are no additional visible components.
14980 elsif Ekind (Scope (Current_Scope)) = E_Package
14981 and then not In_Private_Part (Scope (Current_Scope))
14986 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
14987 and then In_Open_Scopes (Scope (Original_Scope))
14988 and then Is_Local_Type (Type_Scope);
14991 -- There is another weird way in which a component may be invisible
14992 -- when the private and the full view are not derived from the same
14993 -- ancestor. Here is an example :
14995 -- type A1 is tagged record F1 : integer; end record;
14996 -- type A2 is new A1 with record F2 : integer; end record;
14997 -- type T is new A1 with private;
14999 -- type T is new A2 with null record;
15001 -- In this case, the full view of T inherits F1 and F2 but the private
15002 -- view inherits only F1
15006 Ancestor : Entity_Id := Scope (C);
15010 if Ancestor = Original_Scope then
15012 elsif Ancestor = Etype (Ancestor) then
15016 Ancestor := Etype (Ancestor);
15020 end Is_Visible_Component;
15022 --------------------------
15023 -- Make_Class_Wide_Type --
15024 --------------------------
15026 procedure Make_Class_Wide_Type (T : Entity_Id) is
15027 CW_Type : Entity_Id;
15029 Next_E : Entity_Id;
15032 -- The class wide type can have been defined by the partial view, in
15033 -- which case everything is already done.
15035 if Present (Class_Wide_Type (T)) then
15040 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
15042 -- Inherit root type characteristics
15044 CW_Name := Chars (CW_Type);
15045 Next_E := Next_Entity (CW_Type);
15046 Copy_Node (T, CW_Type);
15047 Set_Comes_From_Source (CW_Type, False);
15048 Set_Chars (CW_Type, CW_Name);
15049 Set_Parent (CW_Type, Parent (T));
15050 Set_Next_Entity (CW_Type, Next_E);
15052 -- Ensure we have a new freeze node for the class-wide type. The partial
15053 -- view may have freeze action of its own, requiring a proper freeze
15054 -- node, and the same freeze node cannot be shared between the two
15057 Set_Has_Delayed_Freeze (CW_Type);
15058 Set_Freeze_Node (CW_Type, Empty);
15060 -- Customize the class-wide type: It has no prim. op., it cannot be
15061 -- abstract and its Etype points back to the specific root type.
15063 Set_Ekind (CW_Type, E_Class_Wide_Type);
15064 Set_Is_Tagged_Type (CW_Type, True);
15065 Set_Primitive_Operations (CW_Type, New_Elmt_List);
15066 Set_Is_Abstract_Type (CW_Type, False);
15067 Set_Is_Constrained (CW_Type, False);
15068 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
15070 if Ekind (T) = E_Class_Wide_Subtype then
15071 Set_Etype (CW_Type, Etype (Base_Type (T)));
15073 Set_Etype (CW_Type, T);
15076 -- If this is the class_wide type of a constrained subtype, it does
15077 -- not have discriminants.
15079 Set_Has_Discriminants (CW_Type,
15080 Has_Discriminants (T) and then not Is_Constrained (T));
15082 Set_Has_Unknown_Discriminants (CW_Type, True);
15083 Set_Class_Wide_Type (T, CW_Type);
15084 Set_Equivalent_Type (CW_Type, Empty);
15086 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
15088 Set_Class_Wide_Type (CW_Type, CW_Type);
15089 end Make_Class_Wide_Type;
15095 procedure Make_Index
15097 Related_Nod : Node_Id;
15098 Related_Id : Entity_Id := Empty;
15099 Suffix_Index : Nat := 1)
15103 Def_Id : Entity_Id := Empty;
15104 Found : Boolean := False;
15107 -- For a discrete range used in a constrained array definition and
15108 -- defined by a range, an implicit conversion to the predefined type
15109 -- INTEGER is assumed if each bound is either a numeric literal, a named
15110 -- number, or an attribute, and the type of both bounds (prior to the
15111 -- implicit conversion) is the type universal_integer. Otherwise, both
15112 -- bounds must be of the same discrete type, other than universal
15113 -- integer; this type must be determinable independently of the
15114 -- context, but using the fact that the type must be discrete and that
15115 -- both bounds must have the same type.
15117 -- Character literals also have a universal type in the absence of
15118 -- of additional context, and are resolved to Standard_Character.
15120 if Nkind (I) = N_Range then
15122 -- The index is given by a range constraint. The bounds are known
15123 -- to be of a consistent type.
15125 if not Is_Overloaded (I) then
15128 -- For universal bounds, choose the specific predefined type
15130 if T = Universal_Integer then
15131 T := Standard_Integer;
15133 elsif T = Any_Character then
15134 Ambiguous_Character (Low_Bound (I));
15136 T := Standard_Character;
15139 -- The node may be overloaded because some user-defined operators
15140 -- are available, but if a universal interpretation exists it is
15141 -- also the selected one.
15143 elsif Universal_Interpretation (I) = Universal_Integer then
15144 T := Standard_Integer;
15150 Ind : Interp_Index;
15154 Get_First_Interp (I, Ind, It);
15155 while Present (It.Typ) loop
15156 if Is_Discrete_Type (It.Typ) then
15159 and then not Covers (It.Typ, T)
15160 and then not Covers (T, It.Typ)
15162 Error_Msg_N ("ambiguous bounds in discrete range", I);
15170 Get_Next_Interp (Ind, It);
15173 if T = Any_Type then
15174 Error_Msg_N ("discrete type required for range", I);
15175 Set_Etype (I, Any_Type);
15178 elsif T = Universal_Integer then
15179 T := Standard_Integer;
15184 if not Is_Discrete_Type (T) then
15185 Error_Msg_N ("discrete type required for range", I);
15186 Set_Etype (I, Any_Type);
15190 if Nkind (Low_Bound (I)) = N_Attribute_Reference
15191 and then Attribute_Name (Low_Bound (I)) = Name_First
15192 and then Is_Entity_Name (Prefix (Low_Bound (I)))
15193 and then Is_Type (Entity (Prefix (Low_Bound (I))))
15194 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (I))))
15196 -- The type of the index will be the type of the prefix, as long
15197 -- as the upper bound is 'Last of the same type.
15199 Def_Id := Entity (Prefix (Low_Bound (I)));
15201 if Nkind (High_Bound (I)) /= N_Attribute_Reference
15202 or else Attribute_Name (High_Bound (I)) /= Name_Last
15203 or else not Is_Entity_Name (Prefix (High_Bound (I)))
15204 or else Entity (Prefix (High_Bound (I))) /= Def_Id
15211 Process_Range_Expr_In_Decl (R, T);
15213 elsif Nkind (I) = N_Subtype_Indication then
15215 -- The index is given by a subtype with a range constraint
15217 T := Base_Type (Entity (Subtype_Mark (I)));
15219 if not Is_Discrete_Type (T) then
15220 Error_Msg_N ("discrete type required for range", I);
15221 Set_Etype (I, Any_Type);
15225 R := Range_Expression (Constraint (I));
15228 Process_Range_Expr_In_Decl (R, Entity (Subtype_Mark (I)));
15230 elsif Nkind (I) = N_Attribute_Reference then
15232 -- The parser guarantees that the attribute is a RANGE attribute
15234 -- If the node denotes the range of a type mark, that is also the
15235 -- resulting type, and we do no need to create an Itype for it.
15237 if Is_Entity_Name (Prefix (I))
15238 and then Comes_From_Source (I)
15239 and then Is_Type (Entity (Prefix (I)))
15240 and then Is_Discrete_Type (Entity (Prefix (I)))
15242 Def_Id := Entity (Prefix (I));
15245 Analyze_And_Resolve (I);
15249 -- If none of the above, must be a subtype. We convert this to a
15250 -- range attribute reference because in the case of declared first
15251 -- named subtypes, the types in the range reference can be different
15252 -- from the type of the entity. A range attribute normalizes the
15253 -- reference and obtains the correct types for the bounds.
15255 -- This transformation is in the nature of an expansion, is only
15256 -- done if expansion is active. In particular, it is not done on
15257 -- formal generic types, because we need to retain the name of the
15258 -- original index for instantiation purposes.
15261 if not Is_Entity_Name (I) or else not Is_Type (Entity (I)) then
15262 Error_Msg_N ("invalid subtype mark in discrete range ", I);
15263 Set_Etype (I, Any_Integer);
15267 -- The type mark may be that of an incomplete type. It is only
15268 -- now that we can get the full view, previous analysis does
15269 -- not look specifically for a type mark.
15271 Set_Entity (I, Get_Full_View (Entity (I)));
15272 Set_Etype (I, Entity (I));
15273 Def_Id := Entity (I);
15275 if not Is_Discrete_Type (Def_Id) then
15276 Error_Msg_N ("discrete type required for index", I);
15277 Set_Etype (I, Any_Type);
15282 if Expander_Active then
15284 Make_Attribute_Reference (Sloc (I),
15285 Attribute_Name => Name_Range,
15286 Prefix => Relocate_Node (I)));
15288 -- The original was a subtype mark that does not freeze. This
15289 -- means that the rewritten version must not freeze either.
15291 Set_Must_Not_Freeze (I);
15292 Set_Must_Not_Freeze (Prefix (I));
15294 -- Is order critical??? if so, document why, if not
15295 -- use Analyze_And_Resolve
15297 Analyze_And_Resolve (I);
15301 -- If expander is inactive, type is legal, nothing else to construct
15308 if not Is_Discrete_Type (T) then
15309 Error_Msg_N ("discrete type required for range", I);
15310 Set_Etype (I, Any_Type);
15313 elsif T = Any_Type then
15314 Set_Etype (I, Any_Type);
15318 -- We will now create the appropriate Itype to describe the range, but
15319 -- first a check. If we originally had a subtype, then we just label
15320 -- the range with this subtype. Not only is there no need to construct
15321 -- a new subtype, but it is wrong to do so for two reasons:
15323 -- 1. A legality concern, if we have a subtype, it must not freeze,
15324 -- and the Itype would cause freezing incorrectly
15326 -- 2. An efficiency concern, if we created an Itype, it would not be
15327 -- recognized as the same type for the purposes of eliminating
15328 -- checks in some circumstances.
15330 -- We signal this case by setting the subtype entity in Def_Id
15332 if No (Def_Id) then
15334 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
15335 Set_Etype (Def_Id, Base_Type (T));
15337 if Is_Signed_Integer_Type (T) then
15338 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
15340 elsif Is_Modular_Integer_Type (T) then
15341 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
15344 Set_Ekind (Def_Id, E_Enumeration_Subtype);
15345 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
15346 Set_First_Literal (Def_Id, First_Literal (T));
15349 Set_Size_Info (Def_Id, (T));
15350 Set_RM_Size (Def_Id, RM_Size (T));
15351 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
15353 Set_Scalar_Range (Def_Id, R);
15354 Conditional_Delay (Def_Id, T);
15356 -- In the subtype indication case, if the immediate parent of the
15357 -- new subtype is non-static, then the subtype we create is non-
15358 -- static, even if its bounds are static.
15360 if Nkind (I) = N_Subtype_Indication
15361 and then not Is_Static_Subtype (Entity (Subtype_Mark (I)))
15363 Set_Is_Non_Static_Subtype (Def_Id);
15367 -- Final step is to label the index with this constructed type
15369 Set_Etype (I, Def_Id);
15372 ------------------------------
15373 -- Modular_Type_Declaration --
15374 ------------------------------
15376 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
15377 Mod_Expr : constant Node_Id := Expression (Def);
15380 procedure Set_Modular_Size (Bits : Int);
15381 -- Sets RM_Size to Bits, and Esize to normal word size above this
15383 ----------------------
15384 -- Set_Modular_Size --
15385 ----------------------
15387 procedure Set_Modular_Size (Bits : Int) is
15389 Set_RM_Size (T, UI_From_Int (Bits));
15394 elsif Bits <= 16 then
15395 Init_Esize (T, 16);
15397 elsif Bits <= 32 then
15398 Init_Esize (T, 32);
15401 Init_Esize (T, System_Max_Binary_Modulus_Power);
15404 if not Non_Binary_Modulus (T)
15405 and then Esize (T) = RM_Size (T)
15407 Set_Is_Known_Valid (T);
15409 end Set_Modular_Size;
15411 -- Start of processing for Modular_Type_Declaration
15414 Analyze_And_Resolve (Mod_Expr, Any_Integer);
15416 Set_Ekind (T, E_Modular_Integer_Type);
15417 Init_Alignment (T);
15418 Set_Is_Constrained (T);
15420 if not Is_OK_Static_Expression (Mod_Expr) then
15421 Flag_Non_Static_Expr
15422 ("non-static expression used for modular type bound!", Mod_Expr);
15423 M_Val := 2 ** System_Max_Binary_Modulus_Power;
15425 M_Val := Expr_Value (Mod_Expr);
15429 Error_Msg_N ("modulus value must be positive", Mod_Expr);
15430 M_Val := 2 ** System_Max_Binary_Modulus_Power;
15433 Set_Modulus (T, M_Val);
15435 -- Create bounds for the modular type based on the modulus given in
15436 -- the type declaration and then analyze and resolve those bounds.
15438 Set_Scalar_Range (T,
15439 Make_Range (Sloc (Mod_Expr),
15441 Make_Integer_Literal (Sloc (Mod_Expr), 0),
15443 Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
15445 -- Properly analyze the literals for the range. We do this manually
15446 -- because we can't go calling Resolve, since we are resolving these
15447 -- bounds with the type, and this type is certainly not complete yet!
15449 Set_Etype (Low_Bound (Scalar_Range (T)), T);
15450 Set_Etype (High_Bound (Scalar_Range (T)), T);
15451 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
15452 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
15454 -- Loop through powers of two to find number of bits required
15456 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
15460 if M_Val = 2 ** Bits then
15461 Set_Modular_Size (Bits);
15466 elsif M_Val < 2 ** Bits then
15467 Set_Non_Binary_Modulus (T);
15469 if Bits > System_Max_Nonbinary_Modulus_Power then
15470 Error_Msg_Uint_1 :=
15471 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
15473 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
15474 Set_Modular_Size (System_Max_Binary_Modulus_Power);
15478 -- In the non-binary case, set size as per RM 13.3(55)
15480 Set_Modular_Size (Bits);
15487 -- If we fall through, then the size exceed System.Max_Binary_Modulus
15488 -- so we just signal an error and set the maximum size.
15490 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
15491 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
15493 Set_Modular_Size (System_Max_Binary_Modulus_Power);
15494 Init_Alignment (T);
15496 end Modular_Type_Declaration;
15498 --------------------------
15499 -- New_Concatenation_Op --
15500 --------------------------
15502 procedure New_Concatenation_Op (Typ : Entity_Id) is
15503 Loc : constant Source_Ptr := Sloc (Typ);
15506 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
15507 -- Create abbreviated declaration for the formal of a predefined
15508 -- Operator 'Op' of type 'Typ'
15510 --------------------
15511 -- Make_Op_Formal --
15512 --------------------
15514 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
15515 Formal : Entity_Id;
15517 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
15518 Set_Etype (Formal, Typ);
15519 Set_Mechanism (Formal, Default_Mechanism);
15521 end Make_Op_Formal;
15523 -- Start of processing for New_Concatenation_Op
15526 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
15528 Set_Ekind (Op, E_Operator);
15529 Set_Scope (Op, Current_Scope);
15530 Set_Etype (Op, Typ);
15531 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
15532 Set_Is_Immediately_Visible (Op);
15533 Set_Is_Intrinsic_Subprogram (Op);
15534 Set_Has_Completion (Op);
15535 Append_Entity (Op, Current_Scope);
15537 Set_Name_Entity_Id (Name_Op_Concat, Op);
15539 Append_Entity (Make_Op_Formal (Typ, Op), Op);
15540 Append_Entity (Make_Op_Formal (Typ, Op), Op);
15541 end New_Concatenation_Op;
15543 -------------------------
15544 -- OK_For_Limited_Init --
15545 -------------------------
15547 -- ???Check all calls of this, and compare the conditions under which it's
15550 function OK_For_Limited_Init
15552 Exp : Node_Id) return Boolean
15555 return Is_CPP_Constructor_Call (Exp)
15556 or else (Ada_Version >= Ada_05
15557 and then not Debug_Flag_Dot_L
15558 and then OK_For_Limited_Init_In_05 (Typ, Exp));
15559 end OK_For_Limited_Init;
15561 -------------------------------
15562 -- OK_For_Limited_Init_In_05 --
15563 -------------------------------
15565 function OK_For_Limited_Init_In_05
15567 Exp : Node_Id) return Boolean
15570 -- An object of a limited interface type can be initialized with any
15571 -- expression of a nonlimited descendant type.
15573 if Is_Class_Wide_Type (Typ)
15574 and then Is_Limited_Interface (Typ)
15575 and then not Is_Limited_Type (Etype (Exp))
15580 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
15581 -- case of limited aggregates (including extension aggregates), and
15582 -- function calls. The function call may have been give in prefixed
15583 -- notation, in which case the original node is an indexed component.
15585 case Nkind (Original_Node (Exp)) is
15586 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
15589 when N_Qualified_Expression =>
15591 OK_For_Limited_Init_In_05
15592 (Typ, Expression (Original_Node (Exp)));
15594 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
15595 -- with a function call, the expander has rewritten the call into an
15596 -- N_Type_Conversion node to force displacement of the pointer to
15597 -- reference the component containing the secondary dispatch table.
15598 -- Otherwise a type conversion is not a legal context.
15599 -- A return statement for a build-in-place function returning a
15600 -- synchronized type also introduces an unchecked conversion.
15602 when N_Type_Conversion | N_Unchecked_Type_Conversion =>
15603 return not Comes_From_Source (Exp)
15605 OK_For_Limited_Init_In_05
15606 (Typ, Expression (Original_Node (Exp)));
15608 when N_Indexed_Component | N_Selected_Component =>
15609 return Nkind (Exp) = N_Function_Call;
15611 -- A use of 'Input is a function call, hence allowed. Normally the
15612 -- attribute will be changed to a call, but the attribute by itself
15613 -- can occur with -gnatc.
15615 when N_Attribute_Reference =>
15616 return Attribute_Name (Original_Node (Exp)) = Name_Input;
15621 end OK_For_Limited_Init_In_05;
15623 -------------------------------------------
15624 -- Ordinary_Fixed_Point_Type_Declaration --
15625 -------------------------------------------
15627 procedure Ordinary_Fixed_Point_Type_Declaration
15631 Loc : constant Source_Ptr := Sloc (Def);
15632 Delta_Expr : constant Node_Id := Delta_Expression (Def);
15633 RRS : constant Node_Id := Real_Range_Specification (Def);
15634 Implicit_Base : Entity_Id;
15641 Check_Restriction (No_Fixed_Point, Def);
15643 -- Create implicit base type
15646 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
15647 Set_Etype (Implicit_Base, Implicit_Base);
15649 -- Analyze and process delta expression
15651 Analyze_And_Resolve (Delta_Expr, Any_Real);
15653 Check_Delta_Expression (Delta_Expr);
15654 Delta_Val := Expr_Value_R (Delta_Expr);
15656 Set_Delta_Value (Implicit_Base, Delta_Val);
15658 -- Compute default small from given delta, which is the largest power
15659 -- of two that does not exceed the given delta value.
15669 if Delta_Val < Ureal_1 then
15670 while Delta_Val < Tmp loop
15671 Tmp := Tmp / Ureal_2;
15672 Scale := Scale + 1;
15677 Tmp := Tmp * Ureal_2;
15678 exit when Tmp > Delta_Val;
15679 Scale := Scale - 1;
15683 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
15686 Set_Small_Value (Implicit_Base, Small_Val);
15688 -- If no range was given, set a dummy range
15690 if RRS <= Empty_Or_Error then
15691 Low_Val := -Small_Val;
15692 High_Val := Small_Val;
15694 -- Otherwise analyze and process given range
15698 Low : constant Node_Id := Low_Bound (RRS);
15699 High : constant Node_Id := High_Bound (RRS);
15702 Analyze_And_Resolve (Low, Any_Real);
15703 Analyze_And_Resolve (High, Any_Real);
15704 Check_Real_Bound (Low);
15705 Check_Real_Bound (High);
15707 -- Obtain and set the range
15709 Low_Val := Expr_Value_R (Low);
15710 High_Val := Expr_Value_R (High);
15712 if Low_Val > High_Val then
15713 Error_Msg_NE ("?fixed point type& has null range", Def, T);
15718 -- The range for both the implicit base and the declared first subtype
15719 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
15720 -- set a temporary range in place. Note that the bounds of the base
15721 -- type will be widened to be symmetrical and to fill the available
15722 -- bits when the type is frozen.
15724 -- We could do this with all discrete types, and probably should, but
15725 -- we absolutely have to do it for fixed-point, since the end-points
15726 -- of the range and the size are determined by the small value, which
15727 -- could be reset before the freeze point.
15729 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
15730 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
15732 -- Complete definition of first subtype
15734 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
15735 Set_Etype (T, Implicit_Base);
15736 Init_Size_Align (T);
15737 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
15738 Set_Small_Value (T, Small_Val);
15739 Set_Delta_Value (T, Delta_Val);
15740 Set_Is_Constrained (T);
15742 end Ordinary_Fixed_Point_Type_Declaration;
15744 ----------------------------------------
15745 -- Prepare_Private_Subtype_Completion --
15746 ----------------------------------------
15748 procedure Prepare_Private_Subtype_Completion
15750 Related_Nod : Node_Id)
15752 Id_B : constant Entity_Id := Base_Type (Id);
15753 Full_B : constant Entity_Id := Full_View (Id_B);
15757 if Present (Full_B) then
15759 -- The Base_Type is already completed, we can complete the subtype
15760 -- now. We have to create a new entity with the same name, Thus we
15761 -- can't use Create_Itype.
15763 -- This is messy, should be fixed ???
15765 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
15766 Set_Is_Itype (Full);
15767 Set_Associated_Node_For_Itype (Full, Related_Nod);
15768 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
15771 -- The parent subtype may be private, but the base might not, in some
15772 -- nested instances. In that case, the subtype does not need to be
15773 -- exchanged. It would still be nice to make private subtypes and their
15774 -- bases consistent at all times ???
15776 if Is_Private_Type (Id_B) then
15777 Append_Elmt (Id, Private_Dependents (Id_B));
15780 end Prepare_Private_Subtype_Completion;
15782 ---------------------------
15783 -- Process_Discriminants --
15784 ---------------------------
15786 procedure Process_Discriminants
15788 Prev : Entity_Id := Empty)
15790 Elist : constant Elist_Id := New_Elmt_List;
15793 Discr_Number : Uint;
15794 Discr_Type : Entity_Id;
15795 Default_Present : Boolean := False;
15796 Default_Not_Present : Boolean := False;
15799 -- A composite type other than an array type can have discriminants.
15800 -- On entry, the current scope is the composite type.
15802 -- The discriminants are initially entered into the scope of the type
15803 -- via Enter_Name with the default Ekind of E_Void to prevent premature
15804 -- use, as explained at the end of this procedure.
15806 Discr := First (Discriminant_Specifications (N));
15807 while Present (Discr) loop
15808 Enter_Name (Defining_Identifier (Discr));
15810 -- For navigation purposes we add a reference to the discriminant
15811 -- in the entity for the type. If the current declaration is a
15812 -- completion, place references on the partial view. Otherwise the
15813 -- type is the current scope.
15815 if Present (Prev) then
15817 -- The references go on the partial view, if present. If the
15818 -- partial view has discriminants, the references have been
15819 -- generated already.
15821 if not Has_Discriminants (Prev) then
15822 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
15826 (Current_Scope, Defining_Identifier (Discr), 'd');
15829 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
15830 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
15832 -- Ada 2005 (AI-254)
15834 if Present (Access_To_Subprogram_Definition
15835 (Discriminant_Type (Discr)))
15836 and then Protected_Present (Access_To_Subprogram_Definition
15837 (Discriminant_Type (Discr)))
15840 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
15844 Find_Type (Discriminant_Type (Discr));
15845 Discr_Type := Etype (Discriminant_Type (Discr));
15847 if Error_Posted (Discriminant_Type (Discr)) then
15848 Discr_Type := Any_Type;
15852 if Is_Access_Type (Discr_Type) then
15854 -- Ada 2005 (AI-230): Access discriminant allowed in non-limited
15857 if Ada_Version < Ada_05 then
15858 Check_Access_Discriminant_Requires_Limited
15859 (Discr, Discriminant_Type (Discr));
15862 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
15864 ("(Ada 83) access discriminant not allowed", Discr);
15867 elsif not Is_Discrete_Type (Discr_Type) then
15868 Error_Msg_N ("discriminants must have a discrete or access type",
15869 Discriminant_Type (Discr));
15872 Set_Etype (Defining_Identifier (Discr), Discr_Type);
15874 -- If a discriminant specification includes the assignment compound
15875 -- delimiter followed by an expression, the expression is the default
15876 -- expression of the discriminant; the default expression must be of
15877 -- the type of the discriminant. (RM 3.7.1) Since this expression is
15878 -- a default expression, we do the special preanalysis, since this
15879 -- expression does not freeze (see "Handling of Default and Per-
15880 -- Object Expressions" in spec of package Sem).
15882 if Present (Expression (Discr)) then
15883 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
15885 if Nkind (N) = N_Formal_Type_Declaration then
15887 ("discriminant defaults not allowed for formal type",
15888 Expression (Discr));
15890 -- Tagged types cannot have defaulted discriminants, but a
15891 -- non-tagged private type with defaulted discriminants
15892 -- can have a tagged completion.
15894 elsif Is_Tagged_Type (Current_Scope)
15895 and then Comes_From_Source (N)
15898 ("discriminants of tagged type cannot have defaults",
15899 Expression (Discr));
15902 Default_Present := True;
15903 Append_Elmt (Expression (Discr), Elist);
15905 -- Tag the defining identifiers for the discriminants with
15906 -- their corresponding default expressions from the tree.
15908 Set_Discriminant_Default_Value
15909 (Defining_Identifier (Discr), Expression (Discr));
15913 Default_Not_Present := True;
15916 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
15917 -- Discr_Type but with the null-exclusion attribute
15919 if Ada_Version >= Ada_05 then
15921 -- Ada 2005 (AI-231): Static checks
15923 if Can_Never_Be_Null (Discr_Type) then
15924 Null_Exclusion_Static_Checks (Discr);
15926 elsif Is_Access_Type (Discr_Type)
15927 and then Null_Exclusion_Present (Discr)
15929 -- No need to check itypes because in their case this check
15930 -- was done at their point of creation
15932 and then not Is_Itype (Discr_Type)
15934 if Can_Never_Be_Null (Discr_Type) then
15936 ("`NOT NULL` not allowed (& already excludes null)",
15941 Set_Etype (Defining_Identifier (Discr),
15942 Create_Null_Excluding_Itype
15944 Related_Nod => Discr));
15946 -- Check for improper null exclusion if the type is otherwise
15947 -- legal for a discriminant.
15949 elsif Null_Exclusion_Present (Discr)
15950 and then Is_Discrete_Type (Discr_Type)
15953 ("null exclusion can only apply to an access type", Discr);
15956 -- Ada 2005 (AI-402): access discriminants of nonlimited types
15957 -- can't have defaults. Synchronized types, or types that are
15958 -- explicitly limited are fine, but special tests apply to derived
15959 -- types in generics: in a generic body we have to assume the
15960 -- worst, and therefore defaults are not allowed if the parent is
15961 -- a generic formal private type (see ACATS B370001).
15963 if Is_Access_Type (Discr_Type) then
15964 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
15965 or else not Default_Present
15966 or else Is_Limited_Record (Current_Scope)
15967 or else Is_Concurrent_Type (Current_Scope)
15968 or else Is_Concurrent_Record_Type (Current_Scope)
15969 or else Ekind (Current_Scope) = E_Limited_Private_Type
15971 if not Is_Derived_Type (Current_Scope)
15972 or else not Is_Generic_Type (Etype (Current_Scope))
15973 or else not In_Package_Body (Scope (Etype (Current_Scope)))
15974 or else Limited_Present
15975 (Type_Definition (Parent (Current_Scope)))
15980 Error_Msg_N ("access discriminants of nonlimited types",
15981 Expression (Discr));
15982 Error_Msg_N ("\cannot have defaults", Expression (Discr));
15985 elsif Present (Expression (Discr)) then
15987 ("(Ada 2005) access discriminants of nonlimited types",
15988 Expression (Discr));
15989 Error_Msg_N ("\cannot have defaults", Expression (Discr));
15997 -- An element list consisting of the default expressions of the
15998 -- discriminants is constructed in the above loop and used to set
15999 -- the Discriminant_Constraint attribute for the type. If an object
16000 -- is declared of this (record or task) type without any explicit
16001 -- discriminant constraint given, this element list will form the
16002 -- actual parameters for the corresponding initialization procedure
16005 Set_Discriminant_Constraint (Current_Scope, Elist);
16006 Set_Stored_Constraint (Current_Scope, No_Elist);
16008 -- Default expressions must be provided either for all or for none
16009 -- of the discriminants of a discriminant part. (RM 3.7.1)
16011 if Default_Present and then Default_Not_Present then
16013 ("incomplete specification of defaults for discriminants", N);
16016 -- The use of the name of a discriminant is not allowed in default
16017 -- expressions of a discriminant part if the specification of the
16018 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
16020 -- To detect this, the discriminant names are entered initially with an
16021 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
16022 -- attempt to use a void entity (for example in an expression that is
16023 -- type-checked) produces the error message: premature usage. Now after
16024 -- completing the semantic analysis of the discriminant part, we can set
16025 -- the Ekind of all the discriminants appropriately.
16027 Discr := First (Discriminant_Specifications (N));
16028 Discr_Number := Uint_1;
16029 while Present (Discr) loop
16030 Id := Defining_Identifier (Discr);
16031 Set_Ekind (Id, E_Discriminant);
16032 Init_Component_Location (Id);
16034 Set_Discriminant_Number (Id, Discr_Number);
16036 -- Make sure this is always set, even in illegal programs
16038 Set_Corresponding_Discriminant (Id, Empty);
16040 -- Initialize the Original_Record_Component to the entity itself.
16041 -- Inherit_Components will propagate the right value to
16042 -- discriminants in derived record types.
16044 Set_Original_Record_Component (Id, Id);
16046 -- Create the discriminal for the discriminant
16048 Build_Discriminal (Id);
16051 Discr_Number := Discr_Number + 1;
16054 Set_Has_Discriminants (Current_Scope);
16055 end Process_Discriminants;
16057 -----------------------
16058 -- Process_Full_View --
16059 -----------------------
16061 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
16062 Priv_Parent : Entity_Id;
16063 Full_Parent : Entity_Id;
16064 Full_Indic : Node_Id;
16066 procedure Collect_Implemented_Interfaces
16068 Ifaces : Elist_Id);
16069 -- Ada 2005: Gather all the interfaces that Typ directly or
16070 -- inherently implements. Duplicate entries are not added to
16071 -- the list Ifaces.
16073 ------------------------------------
16074 -- Collect_Implemented_Interfaces --
16075 ------------------------------------
16077 procedure Collect_Implemented_Interfaces
16082 Iface_Elmt : Elmt_Id;
16085 -- Abstract interfaces are only associated with tagged record types
16087 if not Is_Tagged_Type (Typ)
16088 or else not Is_Record_Type (Typ)
16093 -- Recursively climb to the ancestors
16095 if Etype (Typ) /= Typ
16097 -- Protect the frontend against wrong cyclic declarations like:
16099 -- type B is new A with private;
16100 -- type C is new A with private;
16102 -- type B is new C with null record;
16103 -- type C is new B with null record;
16105 and then Etype (Typ) /= Priv_T
16106 and then Etype (Typ) /= Full_T
16108 -- Keep separate the management of private type declarations
16110 if Ekind (Typ) = E_Record_Type_With_Private then
16112 -- Handle the following erronous case:
16113 -- type Private_Type is tagged private;
16115 -- type Private_Type is new Type_Implementing_Iface;
16117 if Present (Full_View (Typ))
16118 and then Etype (Typ) /= Full_View (Typ)
16120 if Is_Interface (Etype (Typ)) then
16121 Append_Unique_Elmt (Etype (Typ), Ifaces);
16124 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
16127 -- Non-private types
16130 if Is_Interface (Etype (Typ)) then
16131 Append_Unique_Elmt (Etype (Typ), Ifaces);
16134 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
16138 -- Handle entities in the list of abstract interfaces
16140 if Present (Interfaces (Typ)) then
16141 Iface_Elmt := First_Elmt (Interfaces (Typ));
16142 while Present (Iface_Elmt) loop
16143 Iface := Node (Iface_Elmt);
16145 pragma Assert (Is_Interface (Iface));
16147 if not Contain_Interface (Iface, Ifaces) then
16148 Append_Elmt (Iface, Ifaces);
16149 Collect_Implemented_Interfaces (Iface, Ifaces);
16152 Next_Elmt (Iface_Elmt);
16155 end Collect_Implemented_Interfaces;
16157 -- Start of processing for Process_Full_View
16160 -- First some sanity checks that must be done after semantic
16161 -- decoration of the full view and thus cannot be placed with other
16162 -- similar checks in Find_Type_Name
16164 if not Is_Limited_Type (Priv_T)
16165 and then (Is_Limited_Type (Full_T)
16166 or else Is_Limited_Composite (Full_T))
16169 ("completion of nonlimited type cannot be limited", Full_T);
16170 Explain_Limited_Type (Full_T, Full_T);
16172 elsif Is_Abstract_Type (Full_T)
16173 and then not Is_Abstract_Type (Priv_T)
16176 ("completion of nonabstract type cannot be abstract", Full_T);
16178 elsif Is_Tagged_Type (Priv_T)
16179 and then Is_Limited_Type (Priv_T)
16180 and then not Is_Limited_Type (Full_T)
16182 -- If pragma CPP_Class was applied to the private declaration
16183 -- propagate the limitedness to the full-view
16185 if Is_CPP_Class (Priv_T) then
16186 Set_Is_Limited_Record (Full_T);
16188 -- GNAT allow its own definition of Limited_Controlled to disobey
16189 -- this rule in order in ease the implementation. The next test is
16190 -- safe because Root_Controlled is defined in a private system child
16192 elsif Etype (Full_T) = Full_View (RTE (RE_Root_Controlled)) then
16193 Set_Is_Limited_Composite (Full_T);
16196 ("completion of limited tagged type must be limited", Full_T);
16199 elsif Is_Generic_Type (Priv_T) then
16200 Error_Msg_N ("generic type cannot have a completion", Full_T);
16203 -- Check that ancestor interfaces of private and full views are
16204 -- consistent. We omit this check for synchronized types because
16205 -- they are performed on the corresponding record type when frozen.
16207 if Ada_Version >= Ada_05
16208 and then Is_Tagged_Type (Priv_T)
16209 and then Is_Tagged_Type (Full_T)
16210 and then not Is_Concurrent_Type (Full_T)
16214 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
16215 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
16218 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
16219 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
16221 -- Ada 2005 (AI-251): The partial view shall be a descendant of
16222 -- an interface type if and only if the full type is descendant
16223 -- of the interface type (AARM 7.3 (7.3/2).
16225 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
16227 if Present (Iface) then
16228 Error_Msg_NE ("interface & not implemented by full type " &
16229 "(RM-2005 7.3 (7.3/2))", Priv_T, Iface);
16232 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
16234 if Present (Iface) then
16235 Error_Msg_NE ("interface & not implemented by partial view " &
16236 "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
16241 if Is_Tagged_Type (Priv_T)
16242 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
16243 and then Is_Derived_Type (Full_T)
16245 Priv_Parent := Etype (Priv_T);
16247 -- The full view of a private extension may have been transformed
16248 -- into an unconstrained derived type declaration and a subtype
16249 -- declaration (see build_derived_record_type for details).
16251 if Nkind (N) = N_Subtype_Declaration then
16252 Full_Indic := Subtype_Indication (N);
16253 Full_Parent := Etype (Base_Type (Full_T));
16255 Full_Indic := Subtype_Indication (Type_Definition (N));
16256 Full_Parent := Etype (Full_T);
16259 -- Check that the parent type of the full type is a descendant of
16260 -- the ancestor subtype given in the private extension. If either
16261 -- entity has an Etype equal to Any_Type then we had some previous
16262 -- error situation [7.3(8)].
16264 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
16267 -- Ada 2005 (AI-251): Interfaces in the full-typ can be given in
16268 -- any order. Therefore we don't have to check that its parent must
16269 -- be a descendant of the parent of the private type declaration.
16271 elsif Is_Interface (Priv_Parent)
16272 and then Is_Interface (Full_Parent)
16276 -- Ada 2005 (AI-251): If the parent of the private type declaration
16277 -- is an interface there is no need to check that it is an ancestor
16278 -- of the associated full type declaration. The required tests for
16279 -- this case are performed by Build_Derived_Record_Type.
16281 elsif not Is_Interface (Base_Type (Priv_Parent))
16282 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
16285 ("parent of full type must descend from parent"
16286 & " of private extension", Full_Indic);
16288 -- Check the rules of 7.3(10): if the private extension inherits
16289 -- known discriminants, then the full type must also inherit those
16290 -- discriminants from the same (ancestor) type, and the parent
16291 -- subtype of the full type must be constrained if and only if
16292 -- the ancestor subtype of the private extension is constrained.
16294 elsif No (Discriminant_Specifications (Parent (Priv_T)))
16295 and then not Has_Unknown_Discriminants (Priv_T)
16296 and then Has_Discriminants (Base_Type (Priv_Parent))
16299 Priv_Indic : constant Node_Id :=
16300 Subtype_Indication (Parent (Priv_T));
16302 Priv_Constr : constant Boolean :=
16303 Is_Constrained (Priv_Parent)
16305 Nkind (Priv_Indic) = N_Subtype_Indication
16306 or else Is_Constrained (Entity (Priv_Indic));
16308 Full_Constr : constant Boolean :=
16309 Is_Constrained (Full_Parent)
16311 Nkind (Full_Indic) = N_Subtype_Indication
16312 or else Is_Constrained (Entity (Full_Indic));
16314 Priv_Discr : Entity_Id;
16315 Full_Discr : Entity_Id;
16318 Priv_Discr := First_Discriminant (Priv_Parent);
16319 Full_Discr := First_Discriminant (Full_Parent);
16320 while Present (Priv_Discr) and then Present (Full_Discr) loop
16321 if Original_Record_Component (Priv_Discr) =
16322 Original_Record_Component (Full_Discr)
16324 Corresponding_Discriminant (Priv_Discr) =
16325 Corresponding_Discriminant (Full_Discr)
16332 Next_Discriminant (Priv_Discr);
16333 Next_Discriminant (Full_Discr);
16336 if Present (Priv_Discr) or else Present (Full_Discr) then
16338 ("full view must inherit discriminants of the parent type"
16339 & " used in the private extension", Full_Indic);
16341 elsif Priv_Constr and then not Full_Constr then
16343 ("parent subtype of full type must be constrained",
16346 elsif Full_Constr and then not Priv_Constr then
16348 ("parent subtype of full type must be unconstrained",
16353 -- Check the rules of 7.3(12): if a partial view has neither known
16354 -- or unknown discriminants, then the full type declaration shall
16355 -- define a definite subtype.
16357 elsif not Has_Unknown_Discriminants (Priv_T)
16358 and then not Has_Discriminants (Priv_T)
16359 and then not Is_Constrained (Full_T)
16362 ("full view must define a constrained type if partial view"
16363 & " has no discriminants", Full_T);
16366 -- ??????? Do we implement the following properly ?????
16367 -- If the ancestor subtype of a private extension has constrained
16368 -- discriminants, then the parent subtype of the full view shall
16369 -- impose a statically matching constraint on those discriminants
16373 -- For untagged types, verify that a type without discriminants
16374 -- is not completed with an unconstrained type.
16376 if not Is_Indefinite_Subtype (Priv_T)
16377 and then Is_Indefinite_Subtype (Full_T)
16379 Error_Msg_N ("full view of type must be definite subtype", Full_T);
16383 -- AI-419: verify that the use of "limited" is consistent
16386 Orig_Decl : constant Node_Id := Original_Node (N);
16389 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
16390 and then not Limited_Present (Parent (Priv_T))
16391 and then not Synchronized_Present (Parent (Priv_T))
16392 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
16394 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
16395 and then Limited_Present (Type_Definition (Orig_Decl))
16398 ("full view of non-limited extension cannot be limited", N);
16402 -- Ada 2005 (AI-443): A synchronized private extension must be
16403 -- completed by a task or protected type.
16405 if Ada_Version >= Ada_05
16406 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
16407 and then Synchronized_Present (Parent (Priv_T))
16408 and then not Is_Concurrent_Type (Full_T)
16410 Error_Msg_N ("full view of synchronized extension must " &
16411 "be synchronized type", N);
16414 -- Ada 2005 AI-363: if the full view has discriminants with
16415 -- defaults, it is illegal to declare constrained access subtypes
16416 -- whose designated type is the current type. This allows objects
16417 -- of the type that are declared in the heap to be unconstrained.
16419 if not Has_Unknown_Discriminants (Priv_T)
16420 and then not Has_Discriminants (Priv_T)
16421 and then Has_Discriminants (Full_T)
16423 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
16425 Set_Has_Constrained_Partial_View (Full_T);
16426 Set_Has_Constrained_Partial_View (Priv_T);
16429 -- Create a full declaration for all its subtypes recorded in
16430 -- Private_Dependents and swap them similarly to the base type. These
16431 -- are subtypes that have been define before the full declaration of
16432 -- the private type. We also swap the entry in Private_Dependents list
16433 -- so we can properly restore the private view on exit from the scope.
16436 Priv_Elmt : Elmt_Id;
16441 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
16442 while Present (Priv_Elmt) loop
16443 Priv := Node (Priv_Elmt);
16445 if Ekind (Priv) = E_Private_Subtype
16446 or else Ekind (Priv) = E_Limited_Private_Subtype
16447 or else Ekind (Priv) = E_Record_Subtype_With_Private
16449 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
16450 Set_Is_Itype (Full);
16451 Set_Parent (Full, Parent (Priv));
16452 Set_Associated_Node_For_Itype (Full, N);
16454 -- Now we need to complete the private subtype, but since the
16455 -- base type has already been swapped, we must also swap the
16456 -- subtypes (and thus, reverse the arguments in the call to
16457 -- Complete_Private_Subtype).
16459 Copy_And_Swap (Priv, Full);
16460 Complete_Private_Subtype (Full, Priv, Full_T, N);
16461 Replace_Elmt (Priv_Elmt, Full);
16464 Next_Elmt (Priv_Elmt);
16468 -- If the private view was tagged, copy the new primitive operations
16469 -- from the private view to the full view.
16471 if Is_Tagged_Type (Full_T) then
16473 Disp_Typ : Entity_Id;
16474 Full_List : Elist_Id;
16476 Prim_Elmt : Elmt_Id;
16477 Priv_List : Elist_Id;
16481 L : Elist_Id) return Boolean;
16482 -- Determine whether list L contains element E
16490 L : Elist_Id) return Boolean
16492 List_Elmt : Elmt_Id;
16495 List_Elmt := First_Elmt (L);
16496 while Present (List_Elmt) loop
16497 if Node (List_Elmt) = E then
16501 Next_Elmt (List_Elmt);
16507 -- Start of processing
16510 if Is_Tagged_Type (Priv_T) then
16511 Priv_List := Primitive_Operations (Priv_T);
16512 Prim_Elmt := First_Elmt (Priv_List);
16514 -- In the case of a concurrent type completing a private tagged
16515 -- type, primitives may have been declared in between the two
16516 -- views. These subprograms need to be wrapped the same way
16517 -- entries and protected procedures are handled because they
16518 -- cannot be directly shared by the two views.
16520 if Is_Concurrent_Type (Full_T) then
16522 Conc_Typ : constant Entity_Id :=
16523 Corresponding_Record_Type (Full_T);
16524 Curr_Nod : Node_Id := Parent (Conc_Typ);
16525 Wrap_Spec : Node_Id;
16528 while Present (Prim_Elmt) loop
16529 Prim := Node (Prim_Elmt);
16531 if Comes_From_Source (Prim)
16532 and then not Is_Abstract_Subprogram (Prim)
16535 Make_Subprogram_Declaration (Sloc (Prim),
16539 Obj_Typ => Conc_Typ,
16541 Parameter_Specifications (
16544 Insert_After (Curr_Nod, Wrap_Spec);
16545 Curr_Nod := Wrap_Spec;
16547 Analyze (Wrap_Spec);
16550 Next_Elmt (Prim_Elmt);
16556 -- For non-concurrent types, transfer explicit primitives, but
16557 -- omit those inherited from the parent of the private view
16558 -- since they will be re-inherited later on.
16561 Full_List := Primitive_Operations (Full_T);
16563 while Present (Prim_Elmt) loop
16564 Prim := Node (Prim_Elmt);
16566 if Comes_From_Source (Prim)
16567 and then not Contains (Prim, Full_List)
16569 Append_Elmt (Prim, Full_List);
16572 Next_Elmt (Prim_Elmt);
16576 -- Untagged private view
16579 Full_List := Primitive_Operations (Full_T);
16581 -- In this case the partial view is untagged, so here we locate
16582 -- all of the earlier primitives that need to be treated as
16583 -- dispatching (those that appear between the two views). Note
16584 -- that these additional operations must all be new operations
16585 -- (any earlier operations that override inherited operations
16586 -- of the full view will already have been inserted in the
16587 -- primitives list, marked by Check_Operation_From_Private_View
16588 -- as dispatching. Note that implicit "/=" operators are
16589 -- excluded from being added to the primitives list since they
16590 -- shouldn't be treated as dispatching (tagged "/=" is handled
16593 Prim := Next_Entity (Full_T);
16594 while Present (Prim) and then Prim /= Priv_T loop
16595 if Ekind (Prim) = E_Procedure
16597 Ekind (Prim) = E_Function
16599 Disp_Typ := Find_Dispatching_Type (Prim);
16601 if Disp_Typ = Full_T
16602 and then (Chars (Prim) /= Name_Op_Ne
16603 or else Comes_From_Source (Prim))
16605 Check_Controlling_Formals (Full_T, Prim);
16607 if not Is_Dispatching_Operation (Prim) then
16608 Append_Elmt (Prim, Full_List);
16609 Set_Is_Dispatching_Operation (Prim, True);
16610 Set_DT_Position (Prim, No_Uint);
16613 elsif Is_Dispatching_Operation (Prim)
16614 and then Disp_Typ /= Full_T
16617 -- Verify that it is not otherwise controlled by a
16618 -- formal or a return value of type T.
16620 Check_Controlling_Formals (Disp_Typ, Prim);
16624 Next_Entity (Prim);
16628 -- For the tagged case, the two views can share the same
16629 -- Primitive Operation list and the same class wide type.
16630 -- Update attributes of the class-wide type which depend on
16631 -- the full declaration.
16633 if Is_Tagged_Type (Priv_T) then
16634 Set_Primitive_Operations (Priv_T, Full_List);
16635 Set_Class_Wide_Type
16636 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
16638 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
16643 -- Ada 2005 AI 161: Check preelaboratable initialization consistency
16645 if Known_To_Have_Preelab_Init (Priv_T) then
16647 -- Case where there is a pragma Preelaborable_Initialization. We
16648 -- always allow this in predefined units, which is a bit of a kludge,
16649 -- but it means we don't have to struggle to meet the requirements in
16650 -- the RM for having Preelaborable Initialization. Otherwise we
16651 -- require that the type meets the RM rules. But we can't check that
16652 -- yet, because of the rule about overriding Ininitialize, so we
16653 -- simply set a flag that will be checked at freeze time.
16655 if not In_Predefined_Unit (Full_T) then
16656 Set_Must_Have_Preelab_Init (Full_T);
16660 -- If pragma CPP_Class was applied to the private type declaration,
16661 -- propagate it now to the full type declaration.
16663 if Is_CPP_Class (Priv_T) then
16664 Set_Is_CPP_Class (Full_T);
16665 Set_Convention (Full_T, Convention_CPP);
16668 -- If the private view has user specified stream attributes, then so has
16671 if Has_Specified_Stream_Read (Priv_T) then
16672 Set_Has_Specified_Stream_Read (Full_T);
16674 if Has_Specified_Stream_Write (Priv_T) then
16675 Set_Has_Specified_Stream_Write (Full_T);
16677 if Has_Specified_Stream_Input (Priv_T) then
16678 Set_Has_Specified_Stream_Input (Full_T);
16680 if Has_Specified_Stream_Output (Priv_T) then
16681 Set_Has_Specified_Stream_Output (Full_T);
16683 end Process_Full_View;
16685 -----------------------------------
16686 -- Process_Incomplete_Dependents --
16687 -----------------------------------
16689 procedure Process_Incomplete_Dependents
16691 Full_T : Entity_Id;
16694 Inc_Elmt : Elmt_Id;
16695 Priv_Dep : Entity_Id;
16696 New_Subt : Entity_Id;
16698 Disc_Constraint : Elist_Id;
16701 if No (Private_Dependents (Inc_T)) then
16705 -- Itypes that may be generated by the completion of an incomplete
16706 -- subtype are not used by the back-end and not attached to the tree.
16707 -- They are created only for constraint-checking purposes.
16709 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
16710 while Present (Inc_Elmt) loop
16711 Priv_Dep := Node (Inc_Elmt);
16713 if Ekind (Priv_Dep) = E_Subprogram_Type then
16715 -- An Access_To_Subprogram type may have a return type or a
16716 -- parameter type that is incomplete. Replace with the full view.
16718 if Etype (Priv_Dep) = Inc_T then
16719 Set_Etype (Priv_Dep, Full_T);
16723 Formal : Entity_Id;
16726 Formal := First_Formal (Priv_Dep);
16727 while Present (Formal) loop
16728 if Etype (Formal) = Inc_T then
16729 Set_Etype (Formal, Full_T);
16732 Next_Formal (Formal);
16736 elsif Is_Overloadable (Priv_Dep) then
16738 -- A protected operation is never dispatching: only its
16739 -- wrapper operation (which has convention Ada) is.
16741 if Is_Tagged_Type (Full_T)
16742 and then Convention (Priv_Dep) /= Convention_Protected
16745 -- Subprogram has an access parameter whose designated type
16746 -- was incomplete. Reexamine declaration now, because it may
16747 -- be a primitive operation of the full type.
16749 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
16750 Set_Is_Dispatching_Operation (Priv_Dep);
16751 Check_Controlling_Formals (Full_T, Priv_Dep);
16754 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
16756 -- Can happen during processing of a body before the completion
16757 -- of a TA type. Ignore, because spec is also on dependent list.
16761 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
16762 -- corresponding subtype of the full view.
16764 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
16765 Set_Subtype_Indication
16766 (Parent (Priv_Dep), New_Reference_To (Full_T, Sloc (Priv_Dep)));
16767 Set_Etype (Priv_Dep, Full_T);
16768 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
16769 Set_Analyzed (Parent (Priv_Dep), False);
16771 -- Reanalyze the declaration, suppressing the call to
16772 -- Enter_Name to avoid duplicate names.
16774 Analyze_Subtype_Declaration
16775 (N => Parent (Priv_Dep),
16778 -- Dependent is a subtype
16781 -- We build a new subtype indication using the full view of the
16782 -- incomplete parent. The discriminant constraints have been
16783 -- elaborated already at the point of the subtype declaration.
16785 New_Subt := Create_Itype (E_Void, N);
16787 if Has_Discriminants (Full_T) then
16788 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
16790 Disc_Constraint := No_Elist;
16793 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
16794 Set_Full_View (Priv_Dep, New_Subt);
16797 Next_Elmt (Inc_Elmt);
16799 end Process_Incomplete_Dependents;
16801 --------------------------------
16802 -- Process_Range_Expr_In_Decl --
16803 --------------------------------
16805 procedure Process_Range_Expr_In_Decl
16808 Check_List : List_Id := Empty_List;
16809 R_Check_Off : Boolean := False)
16812 R_Checks : Check_Result;
16813 Type_Decl : Node_Id;
16814 Def_Id : Entity_Id;
16817 Analyze_And_Resolve (R, Base_Type (T));
16819 if Nkind (R) = N_Range then
16820 Lo := Low_Bound (R);
16821 Hi := High_Bound (R);
16823 -- We need to ensure validity of the bounds here, because if we
16824 -- go ahead and do the expansion, then the expanded code will get
16825 -- analyzed with range checks suppressed and we miss the check.
16827 Validity_Check_Range (R);
16829 -- If there were errors in the declaration, try and patch up some
16830 -- common mistakes in the bounds. The cases handled are literals
16831 -- which are Integer where the expected type is Real and vice versa.
16832 -- These corrections allow the compilation process to proceed further
16833 -- along since some basic assumptions of the format of the bounds
16836 if Etype (R) = Any_Type then
16838 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
16840 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
16842 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
16844 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
16846 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
16848 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
16850 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
16852 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
16859 -- If the bounds of the range have been mistakenly given as string
16860 -- literals (perhaps in place of character literals), then an error
16861 -- has already been reported, but we rewrite the string literal as a
16862 -- bound of the range's type to avoid blowups in later processing
16863 -- that looks at static values.
16865 if Nkind (Lo) = N_String_Literal then
16867 Make_Attribute_Reference (Sloc (Lo),
16868 Attribute_Name => Name_First,
16869 Prefix => New_Reference_To (T, Sloc (Lo))));
16870 Analyze_And_Resolve (Lo);
16873 if Nkind (Hi) = N_String_Literal then
16875 Make_Attribute_Reference (Sloc (Hi),
16876 Attribute_Name => Name_First,
16877 Prefix => New_Reference_To (T, Sloc (Hi))));
16878 Analyze_And_Resolve (Hi);
16881 -- If bounds aren't scalar at this point then exit, avoiding
16882 -- problems with further processing of the range in this procedure.
16884 if not Is_Scalar_Type (Etype (Lo)) then
16888 -- Resolve (actually Sem_Eval) has checked that the bounds are in
16889 -- then range of the base type. Here we check whether the bounds
16890 -- are in the range of the subtype itself. Note that if the bounds
16891 -- represent the null range the Constraint_Error exception should
16894 -- ??? The following code should be cleaned up as follows
16896 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
16897 -- is done in the call to Range_Check (R, T); below
16899 -- 2. The use of R_Check_Off should be investigated and possibly
16900 -- removed, this would clean up things a bit.
16902 if Is_Null_Range (Lo, Hi) then
16906 -- Capture values of bounds and generate temporaries for them
16907 -- if needed, before applying checks, since checks may cause
16908 -- duplication of the expression without forcing evaluation.
16910 if Expander_Active then
16911 Force_Evaluation (Lo);
16912 Force_Evaluation (Hi);
16915 -- We use a flag here instead of suppressing checks on the
16916 -- type because the type we check against isn't necessarily
16917 -- the place where we put the check.
16919 if not R_Check_Off then
16920 R_Checks := Get_Range_Checks (R, T);
16922 -- Look up tree to find an appropriate insertion point.
16923 -- This seems really junk code, and very brittle, couldn't
16924 -- we just use an insert actions call of some kind ???
16926 Type_Decl := Parent (R);
16927 while Present (Type_Decl) and then not
16928 (Nkind_In (Type_Decl, N_Full_Type_Declaration,
16929 N_Subtype_Declaration,
16931 N_Task_Type_Declaration)
16933 Nkind_In (Type_Decl, N_Single_Task_Declaration,
16934 N_Protected_Type_Declaration,
16935 N_Single_Protected_Declaration))
16937 Type_Decl := Parent (Type_Decl);
16940 -- Why would Type_Decl not be present??? Without this test,
16941 -- short regression tests fail.
16943 if Present (Type_Decl) then
16945 -- Case of loop statement (more comments ???)
16947 if Nkind (Type_Decl) = N_Loop_Statement then
16952 Indic := Parent (R);
16953 while Present (Indic)
16954 and then Nkind (Indic) /= N_Subtype_Indication
16956 Indic := Parent (Indic);
16959 if Present (Indic) then
16960 Def_Id := Etype (Subtype_Mark (Indic));
16962 Insert_Range_Checks
16968 Do_Before => True);
16972 -- All other cases (more comments ???)
16975 Def_Id := Defining_Identifier (Type_Decl);
16977 if (Ekind (Def_Id) = E_Record_Type
16978 and then Depends_On_Discriminant (R))
16980 (Ekind (Def_Id) = E_Protected_Type
16981 and then Has_Discriminants (Def_Id))
16983 Append_Range_Checks
16984 (R_Checks, Check_List, Def_Id, Sloc (Type_Decl), R);
16987 Insert_Range_Checks
16988 (R_Checks, Type_Decl, Def_Id, Sloc (Type_Decl), R);
16996 elsif Expander_Active then
16997 Get_Index_Bounds (R, Lo, Hi);
16998 Force_Evaluation (Lo);
16999 Force_Evaluation (Hi);
17001 end Process_Range_Expr_In_Decl;
17003 --------------------------------------
17004 -- Process_Real_Range_Specification --
17005 --------------------------------------
17007 procedure Process_Real_Range_Specification (Def : Node_Id) is
17008 Spec : constant Node_Id := Real_Range_Specification (Def);
17011 Err : Boolean := False;
17013 procedure Analyze_Bound (N : Node_Id);
17014 -- Analyze and check one bound
17016 -------------------
17017 -- Analyze_Bound --
17018 -------------------
17020 procedure Analyze_Bound (N : Node_Id) is
17022 Analyze_And_Resolve (N, Any_Real);
17024 if not Is_OK_Static_Expression (N) then
17025 Flag_Non_Static_Expr
17026 ("bound in real type definition is not static!", N);
17031 -- Start of processing for Process_Real_Range_Specification
17034 if Present (Spec) then
17035 Lo := Low_Bound (Spec);
17036 Hi := High_Bound (Spec);
17037 Analyze_Bound (Lo);
17038 Analyze_Bound (Hi);
17040 -- If error, clear away junk range specification
17043 Set_Real_Range_Specification (Def, Empty);
17046 end Process_Real_Range_Specification;
17048 ---------------------
17049 -- Process_Subtype --
17050 ---------------------
17052 function Process_Subtype
17054 Related_Nod : Node_Id;
17055 Related_Id : Entity_Id := Empty;
17056 Suffix : Character := ' ') return Entity_Id
17059 Def_Id : Entity_Id;
17060 Error_Node : Node_Id;
17061 Full_View_Id : Entity_Id;
17062 Subtype_Mark_Id : Entity_Id;
17064 May_Have_Null_Exclusion : Boolean;
17066 procedure Check_Incomplete (T : Entity_Id);
17067 -- Called to verify that an incomplete type is not used prematurely
17069 ----------------------
17070 -- Check_Incomplete --
17071 ----------------------
17073 procedure Check_Incomplete (T : Entity_Id) is
17075 -- Ada 2005 (AI-412): Incomplete subtypes are legal
17077 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
17079 not (Ada_Version >= Ada_05
17081 (Nkind (Parent (T)) = N_Subtype_Declaration
17083 (Nkind (Parent (T)) = N_Subtype_Indication
17084 and then Nkind (Parent (Parent (T))) =
17085 N_Subtype_Declaration)))
17087 Error_Msg_N ("invalid use of type before its full declaration", T);
17089 end Check_Incomplete;
17091 -- Start of processing for Process_Subtype
17094 -- Case of no constraints present
17096 if Nkind (S) /= N_Subtype_Indication then
17098 Check_Incomplete (S);
17101 -- Ada 2005 (AI-231): Static check
17103 if Ada_Version >= Ada_05
17104 and then Present (P)
17105 and then Null_Exclusion_Present (P)
17106 and then Nkind (P) /= N_Access_To_Object_Definition
17107 and then not Is_Access_Type (Entity (S))
17109 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
17112 -- The following is ugly, can't we have a range or even a flag???
17114 May_Have_Null_Exclusion :=
17115 Nkind_In (P, N_Access_Definition,
17116 N_Access_Function_Definition,
17117 N_Access_Procedure_Definition,
17118 N_Access_To_Object_Definition,
17120 N_Component_Definition)
17122 Nkind_In (P, N_Derived_Type_Definition,
17123 N_Discriminant_Specification,
17124 N_Formal_Object_Declaration,
17125 N_Object_Declaration,
17126 N_Object_Renaming_Declaration,
17127 N_Parameter_Specification,
17128 N_Subtype_Declaration);
17130 -- Create an Itype that is a duplicate of Entity (S) but with the
17131 -- null-exclusion attribute
17133 if May_Have_Null_Exclusion
17134 and then Is_Access_Type (Entity (S))
17135 and then Null_Exclusion_Present (P)
17137 -- No need to check the case of an access to object definition.
17138 -- It is correct to define double not-null pointers.
17141 -- type Not_Null_Int_Ptr is not null access Integer;
17142 -- type Acc is not null access Not_Null_Int_Ptr;
17144 and then Nkind (P) /= N_Access_To_Object_Definition
17146 if Can_Never_Be_Null (Entity (S)) then
17147 case Nkind (Related_Nod) is
17148 when N_Full_Type_Declaration =>
17149 if Nkind (Type_Definition (Related_Nod))
17150 in N_Array_Type_Definition
17154 (Component_Definition
17155 (Type_Definition (Related_Nod)));
17158 Subtype_Indication (Type_Definition (Related_Nod));
17161 when N_Subtype_Declaration =>
17162 Error_Node := Subtype_Indication (Related_Nod);
17164 when N_Object_Declaration =>
17165 Error_Node := Object_Definition (Related_Nod);
17167 when N_Component_Declaration =>
17169 Subtype_Indication (Component_Definition (Related_Nod));
17171 when N_Allocator =>
17172 Error_Node := Expression (Related_Nod);
17175 pragma Assert (False);
17176 Error_Node := Related_Nod;
17180 ("`NOT NULL` not allowed (& already excludes null)",
17186 Create_Null_Excluding_Itype
17188 Related_Nod => P));
17189 Set_Entity (S, Etype (S));
17194 -- Case of constraint present, so that we have an N_Subtype_Indication
17195 -- node (this node is created only if constraints are present).
17198 Find_Type (Subtype_Mark (S));
17200 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
17202 (Nkind (Parent (S)) = N_Subtype_Declaration
17203 and then Is_Itype (Defining_Identifier (Parent (S))))
17205 Check_Incomplete (Subtype_Mark (S));
17209 Subtype_Mark_Id := Entity (Subtype_Mark (S));
17211 -- Explicit subtype declaration case
17213 if Nkind (P) = N_Subtype_Declaration then
17214 Def_Id := Defining_Identifier (P);
17216 -- Explicit derived type definition case
17218 elsif Nkind (P) = N_Derived_Type_Definition then
17219 Def_Id := Defining_Identifier (Parent (P));
17221 -- Implicit case, the Def_Id must be created as an implicit type.
17222 -- The one exception arises in the case of concurrent types, array
17223 -- and access types, where other subsidiary implicit types may be
17224 -- created and must appear before the main implicit type. In these
17225 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
17226 -- has not yet been called to create Def_Id.
17229 if Is_Array_Type (Subtype_Mark_Id)
17230 or else Is_Concurrent_Type (Subtype_Mark_Id)
17231 or else Is_Access_Type (Subtype_Mark_Id)
17235 -- For the other cases, we create a new unattached Itype,
17236 -- and set the indication to ensure it gets attached later.
17240 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
17244 -- If the kind of constraint is invalid for this kind of type,
17245 -- then give an error, and then pretend no constraint was given.
17247 if not Is_Valid_Constraint_Kind
17248 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
17251 ("incorrect constraint for this kind of type", Constraint (S));
17253 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
17255 -- Set Ekind of orphan itype, to prevent cascaded errors
17257 if Present (Def_Id) then
17258 Set_Ekind (Def_Id, Ekind (Any_Type));
17261 -- Make recursive call, having got rid of the bogus constraint
17263 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
17266 -- Remaining processing depends on type
17268 case Ekind (Subtype_Mark_Id) is
17269 when Access_Kind =>
17270 Constrain_Access (Def_Id, S, Related_Nod);
17273 and then Is_Itype (Designated_Type (Def_Id))
17274 and then Nkind (Related_Nod) = N_Subtype_Declaration
17275 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
17277 Build_Itype_Reference
17278 (Designated_Type (Def_Id), Related_Nod);
17282 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
17284 when Decimal_Fixed_Point_Kind =>
17285 Constrain_Decimal (Def_Id, S);
17287 when Enumeration_Kind =>
17288 Constrain_Enumeration (Def_Id, S);
17290 when Ordinary_Fixed_Point_Kind =>
17291 Constrain_Ordinary_Fixed (Def_Id, S);
17294 Constrain_Float (Def_Id, S);
17296 when Integer_Kind =>
17297 Constrain_Integer (Def_Id, S);
17299 when E_Record_Type |
17302 E_Incomplete_Type =>
17303 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
17305 if Ekind (Def_Id) = E_Incomplete_Type then
17306 Set_Private_Dependents (Def_Id, New_Elmt_List);
17309 when Private_Kind =>
17310 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
17311 Set_Private_Dependents (Def_Id, New_Elmt_List);
17313 -- In case of an invalid constraint prevent further processing
17314 -- since the type constructed is missing expected fields.
17316 if Etype (Def_Id) = Any_Type then
17320 -- If the full view is that of a task with discriminants,
17321 -- we must constrain both the concurrent type and its
17322 -- corresponding record type. Otherwise we will just propagate
17323 -- the constraint to the full view, if available.
17325 if Present (Full_View (Subtype_Mark_Id))
17326 and then Has_Discriminants (Subtype_Mark_Id)
17327 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
17330 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
17332 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
17333 Constrain_Concurrent (Full_View_Id, S,
17334 Related_Nod, Related_Id, Suffix);
17335 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
17336 Set_Full_View (Def_Id, Full_View_Id);
17338 -- Introduce an explicit reference to the private subtype,
17339 -- to prevent scope anomalies in gigi if first use appears
17340 -- in a nested context, e.g. a later function body.
17341 -- Should this be generated in other contexts than a full
17342 -- type declaration?
17344 if Is_Itype (Def_Id)
17346 Nkind (Parent (P)) = N_Full_Type_Declaration
17348 Build_Itype_Reference (Def_Id, Parent (P));
17352 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
17355 when Concurrent_Kind =>
17356 Constrain_Concurrent (Def_Id, S,
17357 Related_Nod, Related_Id, Suffix);
17360 Error_Msg_N ("invalid subtype mark in subtype indication", S);
17363 -- Size and Convention are always inherited from the base type
17365 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
17366 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
17370 end Process_Subtype;
17372 ---------------------------------------
17373 -- Check_Anonymous_Access_Components --
17374 ---------------------------------------
17376 procedure Check_Anonymous_Access_Components
17377 (Typ_Decl : Node_Id;
17380 Comp_List : Node_Id)
17382 Loc : constant Source_Ptr := Sloc (Typ_Decl);
17383 Anon_Access : Entity_Id;
17386 Comp_Def : Node_Id;
17388 Type_Def : Node_Id;
17390 procedure Build_Incomplete_Type_Declaration;
17391 -- If the record type contains components that include an access to the
17392 -- current record, then create an incomplete type declaration for the
17393 -- record, to be used as the designated type of the anonymous access.
17394 -- This is done only once, and only if there is no previous partial
17395 -- view of the type.
17397 function Designates_T (Subt : Node_Id) return Boolean;
17398 -- Check whether a node designates the enclosing record type, or 'Class
17401 function Mentions_T (Acc_Def : Node_Id) return Boolean;
17402 -- Check whether an access definition includes a reference to
17403 -- the enclosing record type. The reference can be a subtype mark
17404 -- in the access definition itself, a 'Class attribute reference, or
17405 -- recursively a reference appearing in a parameter specification
17406 -- or result definition of an access_to_subprogram definition.
17408 --------------------------------------
17409 -- Build_Incomplete_Type_Declaration --
17410 --------------------------------------
17412 procedure Build_Incomplete_Type_Declaration is
17417 -- Is_Tagged indicates whether the type is tagged. It is tagged if
17418 -- it's "is new ... with record" or else "is tagged record ...".
17420 Is_Tagged : constant Boolean :=
17421 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
17424 (Record_Extension_Part (Type_Definition (Typ_Decl))))
17426 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
17427 and then Tagged_Present (Type_Definition (Typ_Decl)));
17430 -- If there is a previous partial view, no need to create a new one
17431 -- If the partial view, given by Prev, is incomplete, If Prev is
17432 -- a private declaration, full declaration is flagged accordingly.
17434 if Prev /= Typ then
17436 Make_Class_Wide_Type (Prev);
17437 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
17438 Set_Etype (Class_Wide_Type (Typ), Typ);
17443 elsif Has_Private_Declaration (Typ) then
17445 -- If we refer to T'Class inside T, and T is the completion of a
17446 -- private type, then we need to make sure the class-wide type
17450 Make_Class_Wide_Type (Typ);
17455 -- If there was a previous anonymous access type, the incomplete
17456 -- type declaration will have been created already.
17458 elsif Present (Current_Entity (Typ))
17459 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
17460 and then Full_View (Current_Entity (Typ)) = Typ
17465 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
17466 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
17468 -- Type has already been inserted into the current scope.
17469 -- Remove it, and add incomplete declaration for type, so
17470 -- that subsequent anonymous access types can use it.
17471 -- The entity is unchained from the homonym list and from
17472 -- immediate visibility. After analysis, the entity in the
17473 -- incomplete declaration becomes immediately visible in the
17474 -- record declaration that follows.
17476 H := Current_Entity (Typ);
17479 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
17482 and then Homonym (H) /= Typ
17484 H := Homonym (Typ);
17487 Set_Homonym (H, Homonym (Typ));
17490 Insert_Before (Typ_Decl, Decl);
17492 Set_Full_View (Inc_T, Typ);
17495 -- Create a common class-wide type for both views, and set
17496 -- the Etype of the class-wide type to the full view.
17498 Make_Class_Wide_Type (Inc_T);
17499 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
17500 Set_Etype (Class_Wide_Type (Typ), Typ);
17503 end Build_Incomplete_Type_Declaration;
17509 function Designates_T (Subt : Node_Id) return Boolean is
17510 Type_Id : constant Name_Id := Chars (Typ);
17512 function Names_T (Nam : Node_Id) return Boolean;
17513 -- The record type has not been introduced in the current scope
17514 -- yet, so we must examine the name of the type itself, either
17515 -- an identifier T, or an expanded name of the form P.T, where
17516 -- P denotes the current scope.
17522 function Names_T (Nam : Node_Id) return Boolean is
17524 if Nkind (Nam) = N_Identifier then
17525 return Chars (Nam) = Type_Id;
17527 elsif Nkind (Nam) = N_Selected_Component then
17528 if Chars (Selector_Name (Nam)) = Type_Id then
17529 if Nkind (Prefix (Nam)) = N_Identifier then
17530 return Chars (Prefix (Nam)) = Chars (Current_Scope);
17532 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
17533 return Chars (Selector_Name (Prefix (Nam))) =
17534 Chars (Current_Scope);
17548 -- Start of processing for Designates_T
17551 if Nkind (Subt) = N_Identifier then
17552 return Chars (Subt) = Type_Id;
17554 -- Reference can be through an expanded name which has not been
17555 -- analyzed yet, and which designates enclosing scopes.
17557 elsif Nkind (Subt) = N_Selected_Component then
17558 if Names_T (Subt) then
17561 -- Otherwise it must denote an entity that is already visible.
17562 -- The access definition may name a subtype of the enclosing
17563 -- type, if there is a previous incomplete declaration for it.
17566 Find_Selected_Component (Subt);
17568 Is_Entity_Name (Subt)
17569 and then Scope (Entity (Subt)) = Current_Scope
17571 (Chars (Base_Type (Entity (Subt))) = Type_Id
17573 (Is_Class_Wide_Type (Entity (Subt))
17575 Chars (Etype (Base_Type (Entity (Subt)))) =
17579 -- A reference to the current type may appear as the prefix of
17580 -- a 'Class attribute.
17582 elsif Nkind (Subt) = N_Attribute_Reference
17583 and then Attribute_Name (Subt) = Name_Class
17585 return Names_T (Prefix (Subt));
17596 function Mentions_T (Acc_Def : Node_Id) return Boolean is
17597 Param_Spec : Node_Id;
17599 Acc_Subprg : constant Node_Id :=
17600 Access_To_Subprogram_Definition (Acc_Def);
17603 if No (Acc_Subprg) then
17604 return Designates_T (Subtype_Mark (Acc_Def));
17607 -- Component is an access_to_subprogram: examine its formals,
17608 -- and result definition in the case of an access_to_function.
17610 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
17611 while Present (Param_Spec) loop
17612 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
17613 and then Mentions_T (Parameter_Type (Param_Spec))
17617 elsif Designates_T (Parameter_Type (Param_Spec)) then
17624 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
17625 if Nkind (Result_Definition (Acc_Subprg)) =
17626 N_Access_Definition
17628 return Mentions_T (Result_Definition (Acc_Subprg));
17630 return Designates_T (Result_Definition (Acc_Subprg));
17637 -- Start of processing for Check_Anonymous_Access_Components
17640 if No (Comp_List) then
17644 Comp := First (Component_Items (Comp_List));
17645 while Present (Comp) loop
17646 if Nkind (Comp) = N_Component_Declaration
17648 (Access_Definition (Component_Definition (Comp)))
17650 Mentions_T (Access_Definition (Component_Definition (Comp)))
17652 Comp_Def := Component_Definition (Comp);
17654 Access_To_Subprogram_Definition
17655 (Access_Definition (Comp_Def));
17657 Build_Incomplete_Type_Declaration;
17659 Make_Defining_Identifier (Loc,
17660 Chars => New_Internal_Name ('S'));
17662 -- Create a declaration for the anonymous access type: either
17663 -- an access_to_object or an access_to_subprogram.
17665 if Present (Acc_Def) then
17666 if Nkind (Acc_Def) = N_Access_Function_Definition then
17668 Make_Access_Function_Definition (Loc,
17669 Parameter_Specifications =>
17670 Parameter_Specifications (Acc_Def),
17671 Result_Definition => Result_Definition (Acc_Def));
17674 Make_Access_Procedure_Definition (Loc,
17675 Parameter_Specifications =>
17676 Parameter_Specifications (Acc_Def));
17681 Make_Access_To_Object_Definition (Loc,
17682 Subtype_Indication =>
17685 (Access_Definition (Comp_Def))));
17687 Set_Constant_Present
17688 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
17690 (Type_Def, All_Present (Access_Definition (Comp_Def)));
17693 Set_Null_Exclusion_Present
17695 Null_Exclusion_Present (Access_Definition (Comp_Def)));
17698 Make_Full_Type_Declaration (Loc,
17699 Defining_Identifier => Anon_Access,
17700 Type_Definition => Type_Def);
17702 Insert_Before (Typ_Decl, Decl);
17705 -- If an access to object, Preserve entity of designated type,
17706 -- for ASIS use, before rewriting the component definition.
17708 if No (Acc_Def) then
17713 Desig := Entity (Subtype_Indication (Type_Def));
17715 -- If the access definition is to the current record,
17716 -- the visible entity at this point is an incomplete
17717 -- type. Retrieve the full view to simplify ASIS queries
17719 if Ekind (Desig) = E_Incomplete_Type then
17720 Desig := Full_View (Desig);
17724 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
17729 Make_Component_Definition (Loc,
17730 Subtype_Indication =>
17731 New_Occurrence_Of (Anon_Access, Loc)));
17733 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
17734 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
17736 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
17739 Set_Is_Local_Anonymous_Access (Anon_Access);
17745 if Present (Variant_Part (Comp_List)) then
17749 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
17750 while Present (V) loop
17751 Check_Anonymous_Access_Components
17752 (Typ_Decl, Typ, Prev, Component_List (V));
17753 Next_Non_Pragma (V);
17757 end Check_Anonymous_Access_Components;
17759 --------------------------------
17760 -- Preanalyze_Spec_Expression --
17761 --------------------------------
17763 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
17764 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
17766 In_Spec_Expression := True;
17767 Preanalyze_And_Resolve (N, T);
17768 In_Spec_Expression := Save_In_Spec_Expression;
17769 end Preanalyze_Spec_Expression;
17771 -----------------------------
17772 -- Record_Type_Declaration --
17773 -----------------------------
17775 procedure Record_Type_Declaration
17780 Def : constant Node_Id := Type_Definition (N);
17781 Is_Tagged : Boolean;
17782 Tag_Comp : Entity_Id;
17785 -- These flags must be initialized before calling Process_Discriminants
17786 -- because this routine makes use of them.
17788 Set_Ekind (T, E_Record_Type);
17790 Init_Size_Align (T);
17791 Set_Interfaces (T, No_Elist);
17792 Set_Stored_Constraint (T, No_Elist);
17796 if Ada_Version < Ada_05
17797 or else not Interface_Present (Def)
17799 -- The flag Is_Tagged_Type might have already been set by
17800 -- Find_Type_Name if it detected an error for declaration T. This
17801 -- arises in the case of private tagged types where the full view
17802 -- omits the word tagged.
17805 Tagged_Present (Def)
17806 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
17808 Set_Is_Tagged_Type (T, Is_Tagged);
17809 Set_Is_Limited_Record (T, Limited_Present (Def));
17811 -- Type is abstract if full declaration carries keyword, or if
17812 -- previous partial view did.
17814 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
17815 or else Abstract_Present (Def));
17819 Analyze_Interface_Declaration (T, Def);
17821 if Present (Discriminant_Specifications (N)) then
17823 ("interface types cannot have discriminants",
17824 Defining_Identifier
17825 (First (Discriminant_Specifications (N))));
17829 -- First pass: if there are self-referential access components,
17830 -- create the required anonymous access type declarations, and if
17831 -- need be an incomplete type declaration for T itself.
17833 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
17835 if Ada_Version >= Ada_05
17836 and then Present (Interface_List (Def))
17838 Check_Interfaces (N, Def);
17841 Ifaces_List : Elist_Id;
17844 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
17845 -- already in the parents.
17849 Ifaces_List => Ifaces_List,
17850 Exclude_Parents => True);
17852 Set_Interfaces (T, Ifaces_List);
17856 -- Records constitute a scope for the component declarations within.
17857 -- The scope is created prior to the processing of these declarations.
17858 -- Discriminants are processed first, so that they are visible when
17859 -- processing the other components. The Ekind of the record type itself
17860 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
17862 -- Enter record scope
17866 -- If an incomplete or private type declaration was already given for
17867 -- the type, then this scope already exists, and the discriminants have
17868 -- been declared within. We must verify that the full declaration
17869 -- matches the incomplete one.
17871 Check_Or_Process_Discriminants (N, T, Prev);
17873 Set_Is_Constrained (T, not Has_Discriminants (T));
17874 Set_Has_Delayed_Freeze (T, True);
17876 -- For tagged types add a manually analyzed component corresponding
17877 -- to the component _tag, the corresponding piece of tree will be
17878 -- expanded as part of the freezing actions if it is not a CPP_Class.
17882 -- Do not add the tag unless we are in expansion mode
17884 if Expander_Active then
17885 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
17886 Enter_Name (Tag_Comp);
17888 Set_Ekind (Tag_Comp, E_Component);
17889 Set_Is_Tag (Tag_Comp);
17890 Set_Is_Aliased (Tag_Comp);
17891 Set_Etype (Tag_Comp, RTE (RE_Tag));
17892 Set_DT_Entry_Count (Tag_Comp, No_Uint);
17893 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
17894 Init_Component_Location (Tag_Comp);
17896 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
17897 -- implemented interfaces.
17899 if Has_Interfaces (T) then
17900 Add_Interface_Tag_Components (N, T);
17904 Make_Class_Wide_Type (T);
17905 Set_Primitive_Operations (T, New_Elmt_List);
17908 -- We must suppress range checks when processing the components
17909 -- of a record in the presence of discriminants, since we don't
17910 -- want spurious checks to be generated during their analysis, but
17911 -- must reset the Suppress_Range_Checks flags after having processed
17912 -- the record definition.
17914 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
17915 -- couldn't we just use the normal range check suppression method here.
17916 -- That would seem cleaner ???
17918 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
17919 Set_Kill_Range_Checks (T, True);
17920 Record_Type_Definition (Def, Prev);
17921 Set_Kill_Range_Checks (T, False);
17923 Record_Type_Definition (Def, Prev);
17926 -- Exit from record scope
17930 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
17931 -- the implemented interfaces and associate them an aliased entity.
17934 and then not Is_Empty_List (Interface_List (Def))
17936 Derive_Progenitor_Subprograms (T, T);
17938 end Record_Type_Declaration;
17940 ----------------------------
17941 -- Record_Type_Definition --
17942 ----------------------------
17944 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
17945 Component : Entity_Id;
17946 Ctrl_Components : Boolean := False;
17947 Final_Storage_Only : Boolean;
17951 if Ekind (Prev_T) = E_Incomplete_Type then
17952 T := Full_View (Prev_T);
17957 Final_Storage_Only := not Is_Controlled (T);
17959 -- Ada 2005: check whether an explicit Limited is present in a derived
17960 -- type declaration.
17962 if Nkind (Parent (Def)) = N_Derived_Type_Definition
17963 and then Limited_Present (Parent (Def))
17965 Set_Is_Limited_Record (T);
17968 -- If the component list of a record type is defined by the reserved
17969 -- word null and there is no discriminant part, then the record type has
17970 -- no components and all records of the type are null records (RM 3.7)
17971 -- This procedure is also called to process the extension part of a
17972 -- record extension, in which case the current scope may have inherited
17976 or else No (Component_List (Def))
17977 or else Null_Present (Component_List (Def))
17982 Analyze_Declarations (Component_Items (Component_List (Def)));
17984 if Present (Variant_Part (Component_List (Def))) then
17985 Analyze (Variant_Part (Component_List (Def)));
17989 -- After completing the semantic analysis of the record definition,
17990 -- record components, both new and inherited, are accessible. Set their
17991 -- kind accordingly. Exclude malformed itypes from illegal declarations,
17992 -- whose Ekind may be void.
17994 Component := First_Entity (Current_Scope);
17995 while Present (Component) loop
17996 if Ekind (Component) = E_Void
17997 and then not Is_Itype (Component)
17999 Set_Ekind (Component, E_Component);
18000 Init_Component_Location (Component);
18003 if Has_Task (Etype (Component)) then
18007 if Ekind (Component) /= E_Component then
18010 elsif Has_Controlled_Component (Etype (Component))
18011 or else (Chars (Component) /= Name_uParent
18012 and then Is_Controlled (Etype (Component)))
18014 Set_Has_Controlled_Component (T, True);
18015 Final_Storage_Only :=
18017 and then Finalize_Storage_Only (Etype (Component));
18018 Ctrl_Components := True;
18021 Next_Entity (Component);
18024 -- A Type is Finalize_Storage_Only only if all its controlled components
18027 if Ctrl_Components then
18028 Set_Finalize_Storage_Only (T, Final_Storage_Only);
18031 -- Place reference to end record on the proper entity, which may
18032 -- be a partial view.
18034 if Present (Def) then
18035 Process_End_Label (Def, 'e', Prev_T);
18037 end Record_Type_Definition;
18039 ------------------------
18040 -- Replace_Components --
18041 ------------------------
18043 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
18044 function Process (N : Node_Id) return Traverse_Result;
18050 function Process (N : Node_Id) return Traverse_Result is
18054 if Nkind (N) = N_Discriminant_Specification then
18055 Comp := First_Discriminant (Typ);
18056 while Present (Comp) loop
18057 if Chars (Comp) = Chars (Defining_Identifier (N)) then
18058 Set_Defining_Identifier (N, Comp);
18062 Next_Discriminant (Comp);
18065 elsif Nkind (N) = N_Component_Declaration then
18066 Comp := First_Component (Typ);
18067 while Present (Comp) loop
18068 if Chars (Comp) = Chars (Defining_Identifier (N)) then
18069 Set_Defining_Identifier (N, Comp);
18073 Next_Component (Comp);
18080 procedure Replace is new Traverse_Proc (Process);
18082 -- Start of processing for Replace_Components
18086 end Replace_Components;
18088 -------------------------------
18089 -- Set_Completion_Referenced --
18090 -------------------------------
18092 procedure Set_Completion_Referenced (E : Entity_Id) is
18094 -- If in main unit, mark entity that is a completion as referenced,
18095 -- warnings go on the partial view when needed.
18097 if In_Extended_Main_Source_Unit (E) then
18098 Set_Referenced (E);
18100 end Set_Completion_Referenced;
18102 ---------------------
18103 -- Set_Fixed_Range --
18104 ---------------------
18106 -- The range for fixed-point types is complicated by the fact that we
18107 -- do not know the exact end points at the time of the declaration. This
18108 -- is true for three reasons:
18110 -- A size clause may affect the fudging of the end-points
18111 -- A small clause may affect the values of the end-points
18112 -- We try to include the end-points if it does not affect the size
18114 -- This means that the actual end-points must be established at the point
18115 -- when the type is frozen. Meanwhile, we first narrow the range as
18116 -- permitted (so that it will fit if necessary in a small specified size),
18117 -- and then build a range subtree with these narrowed bounds.
18119 -- Set_Fixed_Range constructs the range from real literal values, and sets
18120 -- the range as the Scalar_Range of the given fixed-point type entity.
18122 -- The parent of this range is set to point to the entity so that it is
18123 -- properly hooked into the tree (unlike normal Scalar_Range entries for
18124 -- other scalar types, which are just pointers to the range in the
18125 -- original tree, this would otherwise be an orphan).
18127 -- The tree is left unanalyzed. When the type is frozen, the processing
18128 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
18129 -- analyzed, and uses this as an indication that it should complete
18130 -- work on the range (it will know the final small and size values).
18132 procedure Set_Fixed_Range
18138 S : constant Node_Id :=
18140 Low_Bound => Make_Real_Literal (Loc, Lo),
18141 High_Bound => Make_Real_Literal (Loc, Hi));
18143 Set_Scalar_Range (E, S);
18145 end Set_Fixed_Range;
18147 ----------------------------------
18148 -- Set_Scalar_Range_For_Subtype --
18149 ----------------------------------
18151 procedure Set_Scalar_Range_For_Subtype
18152 (Def_Id : Entity_Id;
18156 Kind : constant Entity_Kind := Ekind (Def_Id);
18159 Set_Scalar_Range (Def_Id, R);
18161 -- We need to link the range into the tree before resolving it so
18162 -- that types that are referenced, including importantly the subtype
18163 -- itself, are properly frozen (Freeze_Expression requires that the
18164 -- expression be properly linked into the tree). Of course if it is
18165 -- already linked in, then we do not disturb the current link.
18167 if No (Parent (R)) then
18168 Set_Parent (R, Def_Id);
18171 -- Reset the kind of the subtype during analysis of the range, to
18172 -- catch possible premature use in the bounds themselves.
18174 Set_Ekind (Def_Id, E_Void);
18175 Process_Range_Expr_In_Decl (R, Subt);
18176 Set_Ekind (Def_Id, Kind);
18177 end Set_Scalar_Range_For_Subtype;
18179 --------------------------------------------------------
18180 -- Set_Stored_Constraint_From_Discriminant_Constraint --
18181 --------------------------------------------------------
18183 procedure Set_Stored_Constraint_From_Discriminant_Constraint
18187 -- Make sure set if encountered during Expand_To_Stored_Constraint
18189 Set_Stored_Constraint (E, No_Elist);
18191 -- Give it the right value
18193 if Is_Constrained (E) and then Has_Discriminants (E) then
18194 Set_Stored_Constraint (E,
18195 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
18197 end Set_Stored_Constraint_From_Discriminant_Constraint;
18199 -------------------------------------
18200 -- Signed_Integer_Type_Declaration --
18201 -------------------------------------
18203 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
18204 Implicit_Base : Entity_Id;
18205 Base_Typ : Entity_Id;
18208 Errs : Boolean := False;
18212 function Can_Derive_From (E : Entity_Id) return Boolean;
18213 -- Determine whether given bounds allow derivation from specified type
18215 procedure Check_Bound (Expr : Node_Id);
18216 -- Check bound to make sure it is integral and static. If not, post
18217 -- appropriate error message and set Errs flag
18219 ---------------------
18220 -- Can_Derive_From --
18221 ---------------------
18223 -- Note we check both bounds against both end values, to deal with
18224 -- strange types like ones with a range of 0 .. -12341234.
18226 function Can_Derive_From (E : Entity_Id) return Boolean is
18227 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
18228 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
18230 return Lo <= Lo_Val and then Lo_Val <= Hi
18232 Lo <= Hi_Val and then Hi_Val <= Hi;
18233 end Can_Derive_From;
18239 procedure Check_Bound (Expr : Node_Id) is
18241 -- If a range constraint is used as an integer type definition, each
18242 -- bound of the range must be defined by a static expression of some
18243 -- integer type, but the two bounds need not have the same integer
18244 -- type (Negative bounds are allowed.) (RM 3.5.4)
18246 if not Is_Integer_Type (Etype (Expr)) then
18248 ("integer type definition bounds must be of integer type", Expr);
18251 elsif not Is_OK_Static_Expression (Expr) then
18252 Flag_Non_Static_Expr
18253 ("non-static expression used for integer type bound!", Expr);
18256 -- The bounds are folded into literals, and we set their type to be
18257 -- universal, to avoid typing difficulties: we cannot set the type
18258 -- of the literal to the new type, because this would be a forward
18259 -- reference for the back end, and if the original type is user-
18260 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
18263 if Is_Entity_Name (Expr) then
18264 Fold_Uint (Expr, Expr_Value (Expr), True);
18267 Set_Etype (Expr, Universal_Integer);
18271 -- Start of processing for Signed_Integer_Type_Declaration
18274 -- Create an anonymous base type
18277 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
18279 -- Analyze and check the bounds, they can be of any integer type
18281 Lo := Low_Bound (Def);
18282 Hi := High_Bound (Def);
18284 -- Arbitrarily use Integer as the type if either bound had an error
18286 if Hi = Error or else Lo = Error then
18287 Base_Typ := Any_Integer;
18288 Set_Error_Posted (T, True);
18290 -- Here both bounds are OK expressions
18293 Analyze_And_Resolve (Lo, Any_Integer);
18294 Analyze_And_Resolve (Hi, Any_Integer);
18300 Hi := Type_High_Bound (Standard_Long_Long_Integer);
18301 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
18304 -- Find type to derive from
18306 Lo_Val := Expr_Value (Lo);
18307 Hi_Val := Expr_Value (Hi);
18309 if Can_Derive_From (Standard_Short_Short_Integer) then
18310 Base_Typ := Base_Type (Standard_Short_Short_Integer);
18312 elsif Can_Derive_From (Standard_Short_Integer) then
18313 Base_Typ := Base_Type (Standard_Short_Integer);
18315 elsif Can_Derive_From (Standard_Integer) then
18316 Base_Typ := Base_Type (Standard_Integer);
18318 elsif Can_Derive_From (Standard_Long_Integer) then
18319 Base_Typ := Base_Type (Standard_Long_Integer);
18321 elsif Can_Derive_From (Standard_Long_Long_Integer) then
18322 Base_Typ := Base_Type (Standard_Long_Long_Integer);
18325 Base_Typ := Base_Type (Standard_Long_Long_Integer);
18326 Error_Msg_N ("integer type definition bounds out of range", Def);
18327 Hi := Type_High_Bound (Standard_Long_Long_Integer);
18328 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
18332 -- Complete both implicit base and declared first subtype entities
18334 Set_Etype (Implicit_Base, Base_Typ);
18335 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
18336 Set_Size_Info (Implicit_Base, (Base_Typ));
18337 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
18338 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
18340 Set_Ekind (T, E_Signed_Integer_Subtype);
18341 Set_Etype (T, Implicit_Base);
18343 Set_Size_Info (T, (Implicit_Base));
18344 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
18345 Set_Scalar_Range (T, Def);
18346 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
18347 Set_Is_Constrained (T);
18348 end Signed_Integer_Type_Declaration;