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 (Anon_Type, Desig_Type);
829 Set_Etype (Anon_Type, Anon_Type);
831 -- Make sure the anonymous access type has size and alignment fields
832 -- set, as required by gigi. This is necessary in the case of the
833 -- Task_Body_Procedure.
835 if not Has_Private_Component (Desig_Type) then
836 Layout_Type (Anon_Type);
839 -- ???The following makes no sense, because Anon_Type is an access type
840 -- and therefore cannot have components, private or otherwise. Hence
841 -- the assertion. Not sure what was meant, here.
842 Set_Depends_On_Private (Anon_Type, Has_Private_Component (Anon_Type));
843 pragma Assert (not Depends_On_Private (Anon_Type));
845 -- Ada 2005 (AI-231): Ada 2005 semantics for anonymous access differs
846 -- from Ada 95 semantics. In Ada 2005, anonymous access must specify if
847 -- the null value is allowed. In Ada 95 the null value is never allowed.
849 if Ada_Version >= Ada_05 then
850 Set_Can_Never_Be_Null (Anon_Type, Null_Exclusion_Present (N));
852 Set_Can_Never_Be_Null (Anon_Type, True);
855 -- The anonymous access type is as public as the discriminated type or
856 -- subprogram that defines it. It is imported (for back-end purposes)
857 -- if the designated type is.
859 Set_Is_Public (Anon_Type, Is_Public (Scope (Anon_Type)));
861 -- Ada 2005 (AI-231): Propagate the access-constant attribute
863 Set_Is_Access_Constant (Anon_Type, Constant_Present (N));
865 -- The context is either a subprogram declaration, object declaration,
866 -- or an access discriminant, in a private or a full type declaration.
867 -- In the case of a subprogram, if the designated type is incomplete,
868 -- the operation will be a primitive operation of the full type, to be
869 -- updated subsequently. If the type is imported through a limited_with
870 -- clause, the subprogram is not a primitive operation of the type
871 -- (which is declared elsewhere in some other scope).
873 if Ekind (Desig_Type) = E_Incomplete_Type
874 and then not From_With_Type (Desig_Type)
875 and then Is_Overloadable (Current_Scope)
877 Append_Elmt (Current_Scope, Private_Dependents (Desig_Type));
878 Set_Has_Delayed_Freeze (Current_Scope);
881 -- Ada 2005: if the designated type is an interface that may contain
882 -- tasks, create a Master entity for the declaration. This must be done
883 -- before expansion of the full declaration, because the declaration may
884 -- include an expression that is an allocator, whose expansion needs the
885 -- proper Master for the created tasks.
887 if Nkind (Related_Nod) = N_Object_Declaration
888 and then Expander_Active
890 if Is_Interface (Desig_Type)
891 and then Is_Limited_Record (Desig_Type)
893 Build_Class_Wide_Master (Anon_Type);
895 -- Similarly, if the type is an anonymous access that designates
896 -- tasks, create a master entity for it in the current context.
898 elsif Has_Task (Desig_Type)
899 and then Comes_From_Source (Related_Nod)
901 if not Has_Master_Entity (Current_Scope) then
903 Make_Object_Declaration (Loc,
904 Defining_Identifier =>
905 Make_Defining_Identifier (Loc, Name_uMaster),
906 Constant_Present => True,
908 New_Reference_To (RTE (RE_Master_Id), Loc),
910 Make_Explicit_Dereference (Loc,
911 New_Reference_To (RTE (RE_Current_Master), Loc)));
913 Insert_Before (Related_Nod, Decl);
916 Set_Master_Id (Anon_Type, Defining_Identifier (Decl));
917 Set_Has_Master_Entity (Current_Scope);
919 Build_Master_Renaming (Related_Nod, Anon_Type);
924 -- For a private component of a protected type, it is imperative that
925 -- the back-end elaborate the type immediately after the protected
926 -- declaration, because this type will be used in the declarations
927 -- created for the component within each protected body, so we must
928 -- create an itype reference for it now.
930 if Nkind (Parent (Related_Nod)) = N_Protected_Definition then
931 Build_Itype_Reference (Anon_Type, Parent (Parent (Related_Nod)));
933 -- Similarly, if the access definition is the return result of a
934 -- function, create an itype reference for it because it will be used
935 -- within the function body. For a regular function that is not a
936 -- compilation unit, insert reference after the declaration. For a
937 -- protected operation, insert it after the enclosing protected type
938 -- declaration. In either case, do not create a reference for a type
939 -- obtained through a limited_with clause, because this would introduce
940 -- semantic dependencies.
942 -- Similarly, do not create a reference if the designated type is a
943 -- generic formal, because no use of it will reach the backend.
945 elsif Nkind (Related_Nod) = N_Function_Specification
946 and then not From_With_Type (Desig_Type)
947 and then not Is_Generic_Type (Desig_Type)
949 if Present (Enclosing_Prot_Type) then
950 Build_Itype_Reference (Anon_Type, Parent (Enclosing_Prot_Type));
952 elsif Is_List_Member (Parent (Related_Nod))
953 and then Nkind (Parent (N)) /= N_Parameter_Specification
955 Build_Itype_Reference (Anon_Type, Parent (Related_Nod));
958 -- Finally, create an itype reference for an object declaration of an
959 -- anonymous access type. This is strictly necessary only for deferred
960 -- constants, but in any case will avoid out-of-scope problems in the
963 elsif Nkind (Related_Nod) = N_Object_Declaration then
964 Build_Itype_Reference (Anon_Type, Related_Nod);
968 end Access_Definition;
970 -----------------------------------
971 -- Access_Subprogram_Declaration --
972 -----------------------------------
974 procedure Access_Subprogram_Declaration
979 procedure Check_For_Premature_Usage (Def : Node_Id);
980 -- Check that type T_Name is not used, directly or recursively, as a
981 -- parameter or a return type in Def. Def is either a subtype, an
982 -- access_definition, or an access_to_subprogram_definition.
984 -------------------------------
985 -- Check_For_Premature_Usage --
986 -------------------------------
988 procedure Check_For_Premature_Usage (Def : Node_Id) is
992 -- Check for a subtype mark
994 if Nkind (Def) in N_Has_Etype then
995 if Etype (Def) = T_Name then
997 ("type& cannot be used before end of its declaration", Def);
1000 -- If this is not a subtype, then this is an access_definition
1002 elsif Nkind (Def) = N_Access_Definition then
1003 if Present (Access_To_Subprogram_Definition (Def)) then
1004 Check_For_Premature_Usage
1005 (Access_To_Subprogram_Definition (Def));
1007 Check_For_Premature_Usage (Subtype_Mark (Def));
1010 -- The only cases left are N_Access_Function_Definition and
1011 -- N_Access_Procedure_Definition.
1014 if Present (Parameter_Specifications (Def)) then
1015 Param := First (Parameter_Specifications (Def));
1016 while Present (Param) loop
1017 Check_For_Premature_Usage (Parameter_Type (Param));
1018 Param := Next (Param);
1022 if Nkind (Def) = N_Access_Function_Definition then
1023 Check_For_Premature_Usage (Result_Definition (Def));
1026 end Check_For_Premature_Usage;
1030 Formals : constant List_Id := Parameter_Specifications (T_Def);
1033 Desig_Type : constant Entity_Id :=
1034 Create_Itype (E_Subprogram_Type, Parent (T_Def));
1036 -- Start of processing for Access_Subprogram_Declaration
1039 -- Associate the Itype node with the inner full-type declaration or
1040 -- subprogram spec. This is required to handle nested anonymous
1041 -- declarations. For example:
1044 -- (X : access procedure
1045 -- (Y : access procedure
1048 D_Ityp := Associated_Node_For_Itype (Desig_Type);
1049 while not (Nkind_In (D_Ityp, N_Full_Type_Declaration,
1050 N_Private_Type_Declaration,
1051 N_Private_Extension_Declaration,
1052 N_Procedure_Specification,
1053 N_Function_Specification)
1055 Nkind_In (D_Ityp, N_Object_Declaration,
1056 N_Object_Renaming_Declaration,
1057 N_Formal_Object_Declaration,
1058 N_Formal_Type_Declaration,
1059 N_Task_Type_Declaration,
1060 N_Protected_Type_Declaration))
1062 D_Ityp := Parent (D_Ityp);
1063 pragma Assert (D_Ityp /= Empty);
1066 Set_Associated_Node_For_Itype (Desig_Type, D_Ityp);
1068 if Nkind_In (D_Ityp, N_Procedure_Specification,
1069 N_Function_Specification)
1071 Set_Scope (Desig_Type, Scope (Defining_Entity (D_Ityp)));
1073 elsif Nkind_In (D_Ityp, N_Full_Type_Declaration,
1074 N_Object_Declaration,
1075 N_Object_Renaming_Declaration,
1076 N_Formal_Type_Declaration)
1078 Set_Scope (Desig_Type, Scope (Defining_Identifier (D_Ityp)));
1081 if Nkind (T_Def) = N_Access_Function_Definition then
1082 if Nkind (Result_Definition (T_Def)) = N_Access_Definition then
1084 Acc : constant Node_Id := Result_Definition (T_Def);
1087 if Present (Access_To_Subprogram_Definition (Acc))
1089 Protected_Present (Access_To_Subprogram_Definition (Acc))
1093 Replace_Anonymous_Access_To_Protected_Subprogram
1099 Access_Definition (T_Def, Result_Definition (T_Def)));
1104 Analyze (Result_Definition (T_Def));
1107 Typ : constant Entity_Id := Entity (Result_Definition (T_Def));
1110 -- If a null exclusion is imposed on the result type, then
1111 -- create a null-excluding itype (an access subtype) and use
1112 -- it as the function's Etype.
1114 if Is_Access_Type (Typ)
1115 and then Null_Exclusion_In_Return_Present (T_Def)
1117 Set_Etype (Desig_Type,
1118 Create_Null_Excluding_Itype
1120 Related_Nod => T_Def,
1121 Scope_Id => Current_Scope));
1124 if From_With_Type (Typ) then
1126 ("illegal use of incomplete type&",
1127 Result_Definition (T_Def), Typ);
1129 elsif Ekind (Current_Scope) = E_Package
1130 and then In_Private_Part (Current_Scope)
1132 if Ekind (Typ) = E_Incomplete_Type then
1133 Append_Elmt (Desig_Type, Private_Dependents (Typ));
1135 elsif Is_Class_Wide_Type (Typ)
1136 and then Ekind (Etype (Typ)) = E_Incomplete_Type
1139 (Desig_Type, Private_Dependents (Etype (Typ)));
1143 Set_Etype (Desig_Type, Typ);
1148 if not (Is_Type (Etype (Desig_Type))) then
1150 ("expect type in function specification",
1151 Result_Definition (T_Def));
1155 Set_Etype (Desig_Type, Standard_Void_Type);
1158 if Present (Formals) then
1159 Push_Scope (Desig_Type);
1161 -- A bit of a kludge here. These kludges will be removed when Itypes
1162 -- have proper parent pointers to their declarations???
1164 -- Kludge 1) Link defining_identifier of formals. Required by
1165 -- First_Formal to provide its functionality.
1171 F := First (Formals);
1172 while Present (F) loop
1173 if No (Parent (Defining_Identifier (F))) then
1174 Set_Parent (Defining_Identifier (F), F);
1181 Process_Formals (Formals, Parent (T_Def));
1183 -- Kludge 2) End_Scope requires that the parent pointer be set to
1184 -- something reasonable, but Itypes don't have parent pointers. So
1185 -- we set it and then unset it ???
1187 Set_Parent (Desig_Type, T_Name);
1189 Set_Parent (Desig_Type, Empty);
1192 -- Check for premature usage of the type being defined
1194 Check_For_Premature_Usage (T_Def);
1196 -- The return type and/or any parameter type may be incomplete. Mark
1197 -- the subprogram_type as depending on the incomplete type, so that
1198 -- it can be updated when the full type declaration is seen. This
1199 -- only applies to incomplete types declared in some enclosing scope,
1200 -- not to limited views from other packages.
1202 if Present (Formals) then
1203 Formal := First_Formal (Desig_Type);
1204 while Present (Formal) loop
1205 if Ekind (Formal) /= E_In_Parameter
1206 and then Nkind (T_Def) = N_Access_Function_Definition
1208 Error_Msg_N ("functions can only have IN parameters", Formal);
1211 if Ekind (Etype (Formal)) = E_Incomplete_Type
1212 and then In_Open_Scopes (Scope (Etype (Formal)))
1214 Append_Elmt (Desig_Type, Private_Dependents (Etype (Formal)));
1215 Set_Has_Delayed_Freeze (Desig_Type);
1218 Next_Formal (Formal);
1222 -- If the return type is incomplete, this is legal as long as the
1223 -- type is declared in the current scope and will be completed in
1224 -- it (rather than being part of limited view).
1226 if Ekind (Etype (Desig_Type)) = E_Incomplete_Type
1227 and then not Has_Delayed_Freeze (Desig_Type)
1228 and then In_Open_Scopes (Scope (Etype (Desig_Type)))
1230 Append_Elmt (Desig_Type, Private_Dependents (Etype (Desig_Type)));
1231 Set_Has_Delayed_Freeze (Desig_Type);
1234 Check_Delayed_Subprogram (Desig_Type);
1236 if Protected_Present (T_Def) then
1237 Set_Ekind (T_Name, E_Access_Protected_Subprogram_Type);
1238 Set_Convention (Desig_Type, Convention_Protected);
1240 Set_Ekind (T_Name, E_Access_Subprogram_Type);
1243 Set_Can_Use_Internal_Rep (T_Name, not Always_Compatible_Rep_On_Target);
1245 Set_Etype (T_Name, T_Name);
1246 Init_Size_Align (T_Name);
1247 Set_Directly_Designated_Type (T_Name, Desig_Type);
1249 -- Ada 2005 (AI-231): Propagate the null-excluding attribute
1251 Set_Can_Never_Be_Null (T_Name, Null_Exclusion_Present (T_Def));
1253 Check_Restriction (No_Access_Subprograms, T_Def);
1254 end Access_Subprogram_Declaration;
1256 ----------------------------
1257 -- Access_Type_Declaration --
1258 ----------------------------
1260 procedure Access_Type_Declaration (T : Entity_Id; Def : Node_Id) is
1261 S : constant Node_Id := Subtype_Indication (Def);
1262 P : constant Node_Id := Parent (Def);
1264 -- Check for permissible use of incomplete type
1266 if Nkind (S) /= N_Subtype_Indication then
1269 if Ekind (Root_Type (Entity (S))) = E_Incomplete_Type then
1270 Set_Directly_Designated_Type (T, Entity (S));
1272 Set_Directly_Designated_Type (T,
1273 Process_Subtype (S, P, T, 'P'));
1277 Set_Directly_Designated_Type (T,
1278 Process_Subtype (S, P, T, 'P'));
1281 if All_Present (Def) or Constant_Present (Def) then
1282 Set_Ekind (T, E_General_Access_Type);
1284 Set_Ekind (T, E_Access_Type);
1287 if Base_Type (Designated_Type (T)) = T then
1288 Error_Msg_N ("access type cannot designate itself", S);
1290 -- In Ada 2005, the type may have a limited view through some unit
1291 -- in its own context, allowing the following circularity that cannot
1292 -- be detected earlier
1294 elsif Is_Class_Wide_Type (Designated_Type (T))
1295 and then Etype (Designated_Type (T)) = T
1298 ("access type cannot designate its own classwide type", S);
1300 -- Clean up indication of tagged status to prevent cascaded errors
1302 Set_Is_Tagged_Type (T, False);
1307 -- If the type has appeared already in a with_type clause, it is
1308 -- frozen and the pointer size is already set. Else, initialize.
1310 if not From_With_Type (T) then
1311 Init_Size_Align (T);
1314 -- Note that Has_Task is always false, since the access type itself
1315 -- is not a task type. See Einfo for more description on this point.
1316 -- Exactly the same consideration applies to Has_Controlled_Component.
1318 Set_Has_Task (T, False);
1319 Set_Has_Controlled_Component (T, False);
1321 -- Initialize Associated_Final_Chain explicitly to Empty, to avoid
1322 -- problems where an incomplete view of this entity has been previously
1323 -- established by a limited with and an overlaid version of this field
1324 -- (Stored_Constraint) was initialized for the incomplete view.
1326 Set_Associated_Final_Chain (T, Empty);
1328 -- Ada 2005 (AI-231): Propagate the null-excluding and access-constant
1331 Set_Can_Never_Be_Null (T, Null_Exclusion_Present (Def));
1332 Set_Is_Access_Constant (T, Constant_Present (Def));
1333 end Access_Type_Declaration;
1335 ----------------------------------
1336 -- Add_Interface_Tag_Components --
1337 ----------------------------------
1339 procedure Add_Interface_Tag_Components (N : Node_Id; Typ : Entity_Id) is
1340 Loc : constant Source_Ptr := Sloc (N);
1344 procedure Add_Tag (Iface : Entity_Id);
1345 -- Add tag for one of the progenitor interfaces
1351 procedure Add_Tag (Iface : Entity_Id) is
1358 pragma Assert (Is_Tagged_Type (Iface)
1359 and then Is_Interface (Iface));
1362 Make_Component_Definition (Loc,
1363 Aliased_Present => True,
1364 Subtype_Indication =>
1365 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc));
1367 Tag := Make_Defining_Identifier (Loc, New_Internal_Name ('V'));
1370 Make_Component_Declaration (Loc,
1371 Defining_Identifier => Tag,
1372 Component_Definition => Def);
1374 Analyze_Component_Declaration (Decl);
1376 Set_Analyzed (Decl);
1377 Set_Ekind (Tag, E_Component);
1379 Set_Is_Aliased (Tag);
1380 Set_Related_Type (Tag, Iface);
1381 Init_Component_Location (Tag);
1383 pragma Assert (Is_Frozen (Iface));
1385 Set_DT_Entry_Count (Tag,
1386 DT_Entry_Count (First_Entity (Iface)));
1388 if No (Last_Tag) then
1391 Insert_After (Last_Tag, Decl);
1396 -- If the ancestor has discriminants we need to give special support
1397 -- to store the offset_to_top value of the secondary dispatch tables.
1398 -- For this purpose we add a supplementary component just after the
1399 -- field that contains the tag associated with each secondary DT.
1401 if Typ /= Etype (Typ)
1402 and then Has_Discriminants (Etype (Typ))
1405 Make_Component_Definition (Loc,
1406 Subtype_Indication =>
1407 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc));
1410 Make_Defining_Identifier (Loc, New_Internal_Name ('V'));
1413 Make_Component_Declaration (Loc,
1414 Defining_Identifier => Offset,
1415 Component_Definition => Def);
1417 Analyze_Component_Declaration (Decl);
1419 Set_Analyzed (Decl);
1420 Set_Ekind (Offset, E_Component);
1421 Set_Is_Aliased (Offset);
1422 Set_Related_Type (Offset, Iface);
1423 Init_Component_Location (Offset);
1424 Insert_After (Last_Tag, Decl);
1435 -- Start of processing for Add_Interface_Tag_Components
1438 if not RTE_Available (RE_Interface_Tag) then
1440 ("(Ada 2005) interface types not supported by this run-time!",
1445 if Ekind (Typ) /= E_Record_Type
1446 or else (Is_Concurrent_Record_Type (Typ)
1447 and then Is_Empty_List (Abstract_Interface_List (Typ)))
1448 or else (not Is_Concurrent_Record_Type (Typ)
1449 and then No (Interfaces (Typ))
1450 and then Is_Empty_Elmt_List (Interfaces (Typ)))
1455 -- Find the current last tag
1457 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1458 Ext := Record_Extension_Part (Type_Definition (N));
1460 pragma Assert (Nkind (Type_Definition (N)) = N_Record_Definition);
1461 Ext := Type_Definition (N);
1466 if not (Present (Component_List (Ext))) then
1467 Set_Null_Present (Ext, False);
1469 Set_Component_List (Ext,
1470 Make_Component_List (Loc,
1471 Component_Items => L,
1472 Null_Present => False));
1474 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
1475 L := Component_Items
1477 (Record_Extension_Part
1478 (Type_Definition (N))));
1480 L := Component_Items
1482 (Type_Definition (N)));
1485 -- Find the last tag component
1488 while Present (Comp) loop
1489 if Nkind (Comp) = N_Component_Declaration
1490 and then Is_Tag (Defining_Identifier (Comp))
1499 -- At this point L references the list of components and Last_Tag
1500 -- references the current last tag (if any). Now we add the tag
1501 -- corresponding with all the interfaces that are not implemented
1504 if Present (Interfaces (Typ)) then
1505 Elmt := First_Elmt (Interfaces (Typ));
1506 while Present (Elmt) loop
1507 Add_Tag (Node (Elmt));
1511 end Add_Interface_Tag_Components;
1513 -------------------------------------
1514 -- Add_Internal_Interface_Entities --
1515 -------------------------------------
1517 procedure Add_Internal_Interface_Entities (Tagged_Type : Entity_Id) is
1520 Iface_Elmt : Elmt_Id;
1521 Iface_Prim : Entity_Id;
1522 Ifaces_List : Elist_Id;
1523 New_Subp : Entity_Id := Empty;
1527 pragma Assert (Ada_Version >= Ada_05
1528 and then Is_Record_Type (Tagged_Type)
1529 and then Is_Tagged_Type (Tagged_Type)
1530 and then Has_Interfaces (Tagged_Type)
1531 and then not Is_Interface (Tagged_Type));
1533 Collect_Interfaces (Tagged_Type, Ifaces_List);
1535 Iface_Elmt := First_Elmt (Ifaces_List);
1536 while Present (Iface_Elmt) loop
1537 Iface := Node (Iface_Elmt);
1539 -- Exclude from this processing interfaces that are parents of
1540 -- Tagged_Type because their primitives are located in the primary
1541 -- dispatch table (and hence no auxiliary internal entities are
1542 -- required to handle secondary dispatch tables in such case).
1544 if not Is_Ancestor (Iface, Tagged_Type) then
1545 Elmt := First_Elmt (Primitive_Operations (Iface));
1546 while Present (Elmt) loop
1547 Iface_Prim := Node (Elmt);
1549 if not Is_Predefined_Dispatching_Operation (Iface_Prim) then
1551 Find_Primitive_Covering_Interface
1552 (Tagged_Type => Tagged_Type,
1553 Iface_Prim => Iface_Prim);
1555 pragma Assert (Present (Prim));
1558 (New_Subp => New_Subp,
1559 Parent_Subp => Iface_Prim,
1560 Derived_Type => Tagged_Type,
1561 Parent_Type => Iface);
1563 -- Ada 2005 (AI-251): Decorate internal entity Iface_Subp
1564 -- associated with interface types. These entities are
1565 -- only registered in the list of primitives of its
1566 -- corresponding tagged type because they are only used
1567 -- to fill the contents of the secondary dispatch tables.
1568 -- Therefore they are removed from the homonym chains.
1570 Set_Is_Hidden (New_Subp);
1571 Set_Is_Internal (New_Subp);
1572 Set_Alias (New_Subp, Prim);
1573 Set_Is_Abstract_Subprogram (New_Subp,
1574 Is_Abstract_Subprogram (Prim));
1575 Set_Interface_Alias (New_Subp, Iface_Prim);
1577 -- Internal entities associated with interface types are
1578 -- only registered in the list of primitives of the tagged
1579 -- type. They are only used to fill the contents of the
1580 -- secondary dispatch tables. Therefore they are not needed
1581 -- in the homonym chains.
1583 Remove_Homonym (New_Subp);
1585 -- Hidden entities associated with interfaces must have set
1586 -- the Has_Delay_Freeze attribute to ensure that, in case of
1587 -- locally defined tagged types (or compiling with static
1588 -- dispatch tables generation disabled) the corresponding
1589 -- entry of the secondary dispatch table is filled when
1590 -- such an entity is frozen.
1592 Set_Has_Delayed_Freeze (New_Subp);
1599 Next_Elmt (Iface_Elmt);
1601 end Add_Internal_Interface_Entities;
1603 -----------------------------------
1604 -- Analyze_Component_Declaration --
1605 -----------------------------------
1607 procedure Analyze_Component_Declaration (N : Node_Id) is
1608 Id : constant Entity_Id := Defining_Identifier (N);
1609 E : constant Node_Id := Expression (N);
1613 function Contains_POC (Constr : Node_Id) return Boolean;
1614 -- Determines whether a constraint uses the discriminant of a record
1615 -- type thus becoming a per-object constraint (POC).
1617 function Is_Known_Limited (Typ : Entity_Id) return Boolean;
1618 -- Typ is the type of the current component, check whether this type is
1619 -- a limited type. Used to validate declaration against that of
1620 -- enclosing record.
1626 function Contains_POC (Constr : Node_Id) return Boolean is
1628 -- Prevent cascaded errors
1630 if Error_Posted (Constr) then
1634 case Nkind (Constr) is
1635 when N_Attribute_Reference =>
1637 Attribute_Name (Constr) = Name_Access
1638 and then Prefix (Constr) = Scope (Entity (Prefix (Constr)));
1640 when N_Discriminant_Association =>
1641 return Denotes_Discriminant (Expression (Constr));
1643 when N_Identifier =>
1644 return Denotes_Discriminant (Constr);
1646 when N_Index_Or_Discriminant_Constraint =>
1651 IDC := First (Constraints (Constr));
1652 while Present (IDC) loop
1654 -- One per-object constraint is sufficient
1656 if Contains_POC (IDC) then
1667 return Denotes_Discriminant (Low_Bound (Constr))
1669 Denotes_Discriminant (High_Bound (Constr));
1671 when N_Range_Constraint =>
1672 return Denotes_Discriminant (Range_Expression (Constr));
1680 ----------------------
1681 -- Is_Known_Limited --
1682 ----------------------
1684 function Is_Known_Limited (Typ : Entity_Id) return Boolean is
1685 P : constant Entity_Id := Etype (Typ);
1686 R : constant Entity_Id := Root_Type (Typ);
1689 if Is_Limited_Record (Typ) then
1692 -- If the root type is limited (and not a limited interface)
1693 -- so is the current type
1695 elsif Is_Limited_Record (R)
1697 (not Is_Interface (R)
1698 or else not Is_Limited_Interface (R))
1702 -- Else the type may have a limited interface progenitor, but a
1703 -- limited record parent.
1706 and then Is_Limited_Record (P)
1713 end Is_Known_Limited;
1715 -- Start of processing for Analyze_Component_Declaration
1718 Generate_Definition (Id);
1721 if Present (Subtype_Indication (Component_Definition (N))) then
1722 T := Find_Type_Of_Object
1723 (Subtype_Indication (Component_Definition (N)), N);
1725 -- Ada 2005 (AI-230): Access Definition case
1728 pragma Assert (Present
1729 (Access_Definition (Component_Definition (N))));
1731 T := Access_Definition
1733 N => Access_Definition (Component_Definition (N)));
1734 Set_Is_Local_Anonymous_Access (T);
1736 -- Ada 2005 (AI-254)
1738 if Present (Access_To_Subprogram_Definition
1739 (Access_Definition (Component_Definition (N))))
1740 and then Protected_Present (Access_To_Subprogram_Definition
1742 (Component_Definition (N))))
1744 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
1748 -- If the subtype is a constrained subtype of the enclosing record,
1749 -- (which must have a partial view) the back-end does not properly
1750 -- handle the recursion. Rewrite the component declaration with an
1751 -- explicit subtype indication, which is acceptable to Gigi. We can copy
1752 -- the tree directly because side effects have already been removed from
1753 -- discriminant constraints.
1755 if Ekind (T) = E_Access_Subtype
1756 and then Is_Entity_Name (Subtype_Indication (Component_Definition (N)))
1757 and then Comes_From_Source (T)
1758 and then Nkind (Parent (T)) = N_Subtype_Declaration
1759 and then Etype (Directly_Designated_Type (T)) = Current_Scope
1762 (Subtype_Indication (Component_Definition (N)),
1763 New_Copy_Tree (Subtype_Indication (Parent (T))));
1764 T := Find_Type_Of_Object
1765 (Subtype_Indication (Component_Definition (N)), N);
1768 -- If the component declaration includes a default expression, then we
1769 -- check that the component is not of a limited type (RM 3.7(5)),
1770 -- and do the special preanalysis of the expression (see section on
1771 -- "Handling of Default and Per-Object Expressions" in the spec of
1775 Preanalyze_Spec_Expression (E, T);
1776 Check_Initialization (T, E);
1778 if Ada_Version >= Ada_05
1779 and then Ekind (T) = E_Anonymous_Access_Type
1780 and then Etype (E) /= Any_Type
1782 -- Check RM 3.9.2(9): "if the expected type for an expression is
1783 -- an anonymous access-to-specific tagged type, then the object
1784 -- designated by the expression shall not be dynamically tagged
1785 -- unless it is a controlling operand in a call on a dispatching
1788 if Is_Tagged_Type (Directly_Designated_Type (T))
1790 Ekind (Directly_Designated_Type (T)) /= E_Class_Wide_Type
1792 Ekind (Directly_Designated_Type (Etype (E))) =
1796 ("access to specific tagged type required (RM 3.9.2(9))", E);
1799 -- (Ada 2005: AI-230): Accessibility check for anonymous
1802 if Type_Access_Level (Etype (E)) > Type_Access_Level (T) then
1804 ("expression has deeper access level than component " &
1805 "(RM 3.10.2 (12.2))", E);
1808 -- The initialization expression is a reference to an access
1809 -- discriminant. The type of the discriminant is always deeper
1810 -- than any access type.
1812 if Ekind (Etype (E)) = E_Anonymous_Access_Type
1813 and then Is_Entity_Name (E)
1814 and then Ekind (Entity (E)) = E_In_Parameter
1815 and then Present (Discriminal_Link (Entity (E)))
1818 ("discriminant has deeper accessibility level than target",
1824 -- The parent type may be a private view with unknown discriminants,
1825 -- and thus unconstrained. Regular components must be constrained.
1827 if Is_Indefinite_Subtype (T) and then Chars (Id) /= Name_uParent then
1828 if Is_Class_Wide_Type (T) then
1830 ("class-wide subtype with unknown discriminants" &
1831 " in component declaration",
1832 Subtype_Indication (Component_Definition (N)));
1835 ("unconstrained subtype in component declaration",
1836 Subtype_Indication (Component_Definition (N)));
1839 -- Components cannot be abstract, except for the special case of
1840 -- the _Parent field (case of extending an abstract tagged type)
1842 elsif Is_Abstract_Type (T) and then Chars (Id) /= Name_uParent then
1843 Error_Msg_N ("type of a component cannot be abstract", N);
1847 Set_Is_Aliased (Id, Aliased_Present (Component_Definition (N)));
1849 -- The component declaration may have a per-object constraint, set
1850 -- the appropriate flag in the defining identifier of the subtype.
1852 if Present (Subtype_Indication (Component_Definition (N))) then
1854 Sindic : constant Node_Id :=
1855 Subtype_Indication (Component_Definition (N));
1857 if Nkind (Sindic) = N_Subtype_Indication
1858 and then Present (Constraint (Sindic))
1859 and then Contains_POC (Constraint (Sindic))
1861 Set_Has_Per_Object_Constraint (Id);
1866 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
1867 -- out some static checks.
1869 if Ada_Version >= Ada_05
1870 and then Can_Never_Be_Null (T)
1872 Null_Exclusion_Static_Checks (N);
1875 -- If this component is private (or depends on a private type), flag the
1876 -- record type to indicate that some operations are not available.
1878 P := Private_Component (T);
1882 -- Check for circular definitions
1884 if P = Any_Type then
1885 Set_Etype (Id, Any_Type);
1887 -- There is a gap in the visibility of operations only if the
1888 -- component type is not defined in the scope of the record type.
1890 elsif Scope (P) = Scope (Current_Scope) then
1893 elsif Is_Limited_Type (P) then
1894 Set_Is_Limited_Composite (Current_Scope);
1897 Set_Is_Private_Composite (Current_Scope);
1902 and then Is_Limited_Type (T)
1903 and then Chars (Id) /= Name_uParent
1904 and then Is_Tagged_Type (Current_Scope)
1906 if Is_Derived_Type (Current_Scope)
1907 and then not Is_Known_Limited (Current_Scope)
1910 ("extension of nonlimited type cannot have limited components",
1913 if Is_Interface (Root_Type (Current_Scope)) then
1915 ("\limitedness is not inherited from limited interface", N);
1917 ("\add LIMITED to type indication", N);
1920 Explain_Limited_Type (T, N);
1921 Set_Etype (Id, Any_Type);
1922 Set_Is_Limited_Composite (Current_Scope, False);
1924 elsif not Is_Derived_Type (Current_Scope)
1925 and then not Is_Limited_Record (Current_Scope)
1926 and then not Is_Concurrent_Type (Current_Scope)
1929 ("nonlimited tagged type cannot have limited components", N);
1930 Explain_Limited_Type (T, N);
1931 Set_Etype (Id, Any_Type);
1932 Set_Is_Limited_Composite (Current_Scope, False);
1936 Set_Original_Record_Component (Id, Id);
1937 end Analyze_Component_Declaration;
1939 --------------------------
1940 -- Analyze_Declarations --
1941 --------------------------
1943 procedure Analyze_Declarations (L : List_Id) is
1945 Freeze_From : Entity_Id := Empty;
1946 Next_Node : Node_Id;
1949 -- Adjust D not to include implicit label declarations, since these
1950 -- have strange Sloc values that result in elaboration check problems.
1951 -- (They have the sloc of the label as found in the source, and that
1952 -- is ahead of the current declarative part).
1958 procedure Adjust_D is
1960 while Present (Prev (D))
1961 and then Nkind (D) = N_Implicit_Label_Declaration
1967 -- Start of processing for Analyze_Declarations
1971 while Present (D) loop
1973 -- Complete analysis of declaration
1976 Next_Node := Next (D);
1978 if No (Freeze_From) then
1979 Freeze_From := First_Entity (Current_Scope);
1982 -- At the end of a declarative part, freeze remaining entities
1983 -- declared in it. The end of the visible declarations of package
1984 -- specification is not the end of a declarative part if private
1985 -- declarations are present. The end of a package declaration is a
1986 -- freezing point only if it a library package. A task definition or
1987 -- protected type definition is not a freeze point either. Finally,
1988 -- we do not freeze entities in generic scopes, because there is no
1989 -- code generated for them and freeze nodes will be generated for
1992 -- The end of a package instantiation is not a freeze point, but
1993 -- for now we make it one, because the generic body is inserted
1994 -- (currently) immediately after. Generic instantiations will not
1995 -- be a freeze point once delayed freezing of bodies is implemented.
1996 -- (This is needed in any case for early instantiations ???).
1998 if No (Next_Node) then
1999 if Nkind_In (Parent (L), N_Component_List,
2001 N_Protected_Definition)
2005 elsif Nkind (Parent (L)) /= N_Package_Specification then
2006 if Nkind (Parent (L)) = N_Package_Body then
2007 Freeze_From := First_Entity (Current_Scope);
2011 Freeze_All (Freeze_From, D);
2012 Freeze_From := Last_Entity (Current_Scope);
2014 elsif Scope (Current_Scope) /= Standard_Standard
2015 and then not Is_Child_Unit (Current_Scope)
2016 and then No (Generic_Parent (Parent (L)))
2020 elsif L /= Visible_Declarations (Parent (L))
2021 or else No (Private_Declarations (Parent (L)))
2022 or else Is_Empty_List (Private_Declarations (Parent (L)))
2025 Freeze_All (Freeze_From, D);
2026 Freeze_From := Last_Entity (Current_Scope);
2029 -- If next node is a body then freeze all types before the body.
2030 -- An exception occurs for some expander-generated bodies. If these
2031 -- are generated at places where in general language rules would not
2032 -- allow a freeze point, then we assume that the expander has
2033 -- explicitly checked that all required types are properly frozen,
2034 -- and we do not cause general freezing here. This special circuit
2035 -- is used when the encountered body is marked as having already
2038 -- In all other cases (bodies that come from source, and expander
2039 -- generated bodies that have not been analyzed yet), freeze all
2040 -- types now. Note that in the latter case, the expander must take
2041 -- care to attach the bodies at a proper place in the tree so as to
2042 -- not cause unwanted freezing at that point.
2044 elsif not Analyzed (Next_Node)
2045 and then (Nkind_In (Next_Node, N_Subprogram_Body,
2051 Nkind (Next_Node) in N_Body_Stub)
2054 Freeze_All (Freeze_From, D);
2055 Freeze_From := Last_Entity (Current_Scope);
2060 end Analyze_Declarations;
2062 ----------------------------------
2063 -- Analyze_Incomplete_Type_Decl --
2064 ----------------------------------
2066 procedure Analyze_Incomplete_Type_Decl (N : Node_Id) is
2067 F : constant Boolean := Is_Pure (Current_Scope);
2071 Generate_Definition (Defining_Identifier (N));
2073 -- Process an incomplete declaration. The identifier must not have been
2074 -- declared already in the scope. However, an incomplete declaration may
2075 -- appear in the private part of a package, for a private type that has
2076 -- already been declared.
2078 -- In this case, the discriminants (if any) must match
2080 T := Find_Type_Name (N);
2082 Set_Ekind (T, E_Incomplete_Type);
2083 Init_Size_Align (T);
2084 Set_Is_First_Subtype (T, True);
2087 -- Ada 2005 (AI-326): Minimum decoration to give support to tagged
2088 -- incomplete types.
2090 if Tagged_Present (N) then
2091 Set_Is_Tagged_Type (T);
2092 Make_Class_Wide_Type (T);
2093 Set_Primitive_Operations (T, New_Elmt_List);
2098 Set_Stored_Constraint (T, No_Elist);
2100 if Present (Discriminant_Specifications (N)) then
2101 Process_Discriminants (N);
2106 -- If the type has discriminants, non-trivial subtypes may be
2107 -- declared before the full view of the type. The full views of those
2108 -- subtypes will be built after the full view of the type.
2110 Set_Private_Dependents (T, New_Elmt_List);
2112 end Analyze_Incomplete_Type_Decl;
2114 -----------------------------------
2115 -- Analyze_Interface_Declaration --
2116 -----------------------------------
2118 procedure Analyze_Interface_Declaration (T : Entity_Id; Def : Node_Id) is
2119 CW : constant Entity_Id := Class_Wide_Type (T);
2122 Set_Is_Tagged_Type (T);
2124 Set_Is_Limited_Record (T, Limited_Present (Def)
2125 or else Task_Present (Def)
2126 or else Protected_Present (Def)
2127 or else Synchronized_Present (Def));
2129 -- Type is abstract if full declaration carries keyword, or if previous
2130 -- partial view did.
2132 Set_Is_Abstract_Type (T);
2133 Set_Is_Interface (T);
2135 -- Type is a limited interface if it includes the keyword limited, task,
2136 -- protected, or synchronized.
2138 Set_Is_Limited_Interface
2139 (T, Limited_Present (Def)
2140 or else Protected_Present (Def)
2141 or else Synchronized_Present (Def)
2142 or else Task_Present (Def));
2144 Set_Is_Protected_Interface (T, Protected_Present (Def));
2145 Set_Is_Task_Interface (T, Task_Present (Def));
2147 -- Type is a synchronized interface if it includes the keyword task,
2148 -- protected, or synchronized.
2150 Set_Is_Synchronized_Interface
2151 (T, Synchronized_Present (Def)
2152 or else Protected_Present (Def)
2153 or else Task_Present (Def));
2155 Set_Interfaces (T, New_Elmt_List);
2156 Set_Primitive_Operations (T, New_Elmt_List);
2158 -- Complete the decoration of the class-wide entity if it was already
2159 -- built (i.e. during the creation of the limited view)
2161 if Present (CW) then
2162 Set_Is_Interface (CW);
2163 Set_Is_Limited_Interface (CW, Is_Limited_Interface (T));
2164 Set_Is_Protected_Interface (CW, Is_Protected_Interface (T));
2165 Set_Is_Synchronized_Interface (CW, Is_Synchronized_Interface (T));
2166 Set_Is_Task_Interface (CW, Is_Task_Interface (T));
2169 -- Check runtime support for synchronized interfaces
2171 if VM_Target = No_VM
2172 and then (Is_Task_Interface (T)
2173 or else Is_Protected_Interface (T)
2174 or else Is_Synchronized_Interface (T))
2175 and then not RTE_Available (RE_Select_Specific_Data)
2177 Error_Msg_CRT ("synchronized interfaces", T);
2179 end Analyze_Interface_Declaration;
2181 -----------------------------
2182 -- Analyze_Itype_Reference --
2183 -----------------------------
2185 -- Nothing to do. This node is placed in the tree only for the benefit of
2186 -- back end processing, and has no effect on the semantic processing.
2188 procedure Analyze_Itype_Reference (N : Node_Id) is
2190 pragma Assert (Is_Itype (Itype (N)));
2192 end Analyze_Itype_Reference;
2194 --------------------------------
2195 -- Analyze_Number_Declaration --
2196 --------------------------------
2198 procedure Analyze_Number_Declaration (N : Node_Id) is
2199 Id : constant Entity_Id := Defining_Identifier (N);
2200 E : constant Node_Id := Expression (N);
2202 Index : Interp_Index;
2206 Generate_Definition (Id);
2209 -- This is an optimization of a common case of an integer literal
2211 if Nkind (E) = N_Integer_Literal then
2212 Set_Is_Static_Expression (E, True);
2213 Set_Etype (E, Universal_Integer);
2215 Set_Etype (Id, Universal_Integer);
2216 Set_Ekind (Id, E_Named_Integer);
2217 Set_Is_Frozen (Id, True);
2221 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2223 -- Process expression, replacing error by integer zero, to avoid
2224 -- cascaded errors or aborts further along in the processing
2226 -- Replace Error by integer zero, which seems least likely to
2227 -- cause cascaded errors.
2230 Rewrite (E, Make_Integer_Literal (Sloc (E), Uint_0));
2231 Set_Error_Posted (E);
2236 -- Verify that the expression is static and numeric. If
2237 -- the expression is overloaded, we apply the preference
2238 -- rule that favors root numeric types.
2240 if not Is_Overloaded (E) then
2246 Get_First_Interp (E, Index, It);
2247 while Present (It.Typ) loop
2248 if (Is_Integer_Type (It.Typ)
2249 or else Is_Real_Type (It.Typ))
2250 and then (Scope (Base_Type (It.Typ))) = Standard_Standard
2252 if T = Any_Type then
2255 elsif It.Typ = Universal_Real
2256 or else It.Typ = Universal_Integer
2258 -- Choose universal interpretation over any other
2265 Get_Next_Interp (Index, It);
2269 if Is_Integer_Type (T) then
2271 Set_Etype (Id, Universal_Integer);
2272 Set_Ekind (Id, E_Named_Integer);
2274 elsif Is_Real_Type (T) then
2276 -- Because the real value is converted to universal_real, this is a
2277 -- legal context for a universal fixed expression.
2279 if T = Universal_Fixed then
2281 Loc : constant Source_Ptr := Sloc (N);
2282 Conv : constant Node_Id := Make_Type_Conversion (Loc,
2284 New_Occurrence_Of (Universal_Real, Loc),
2285 Expression => Relocate_Node (E));
2292 elsif T = Any_Fixed then
2293 Error_Msg_N ("illegal context for mixed mode operation", E);
2295 -- Expression is of the form : universal_fixed * integer. Try to
2296 -- resolve as universal_real.
2298 T := Universal_Real;
2303 Set_Etype (Id, Universal_Real);
2304 Set_Ekind (Id, E_Named_Real);
2307 Wrong_Type (E, Any_Numeric);
2311 Set_Ekind (Id, E_Constant);
2312 Set_Never_Set_In_Source (Id, True);
2313 Set_Is_True_Constant (Id, True);
2317 if Nkind_In (E, N_Integer_Literal, N_Real_Literal) then
2318 Set_Etype (E, Etype (Id));
2321 if not Is_OK_Static_Expression (E) then
2322 Flag_Non_Static_Expr
2323 ("non-static expression used in number declaration!", E);
2324 Rewrite (E, Make_Integer_Literal (Sloc (N), 1));
2325 Set_Etype (E, Any_Type);
2327 end Analyze_Number_Declaration;
2329 --------------------------------
2330 -- Analyze_Object_Declaration --
2331 --------------------------------
2333 procedure Analyze_Object_Declaration (N : Node_Id) is
2334 Loc : constant Source_Ptr := Sloc (N);
2335 Id : constant Entity_Id := Defining_Identifier (N);
2339 E : Node_Id := Expression (N);
2340 -- E is set to Expression (N) throughout this routine. When
2341 -- Expression (N) is modified, E is changed accordingly.
2343 Prev_Entity : Entity_Id := Empty;
2345 function Count_Tasks (T : Entity_Id) return Uint;
2346 -- This function is called when a non-generic library level object of a
2347 -- task type is declared. Its function is to count the static number of
2348 -- tasks declared within the type (it is only called if Has_Tasks is set
2349 -- for T). As a side effect, if an array of tasks with non-static bounds
2350 -- or a variant record type is encountered, Check_Restrictions is called
2351 -- indicating the count is unknown.
2357 function Count_Tasks (T : Entity_Id) return Uint is
2363 if Is_Task_Type (T) then
2366 elsif Is_Record_Type (T) then
2367 if Has_Discriminants (T) then
2368 Check_Restriction (Max_Tasks, N);
2373 C := First_Component (T);
2374 while Present (C) loop
2375 V := V + Count_Tasks (Etype (C));
2382 elsif Is_Array_Type (T) then
2383 X := First_Index (T);
2384 V := Count_Tasks (Component_Type (T));
2385 while Present (X) loop
2388 if not Is_Static_Subtype (C) then
2389 Check_Restriction (Max_Tasks, N);
2392 V := V * (UI_Max (Uint_0,
2393 Expr_Value (Type_High_Bound (C)) -
2394 Expr_Value (Type_Low_Bound (C)) + Uint_1));
2407 -- Start of processing for Analyze_Object_Declaration
2410 -- There are three kinds of implicit types generated by an
2411 -- object declaration:
2413 -- 1. Those for generated by the original Object Definition
2415 -- 2. Those generated by the Expression
2417 -- 3. Those used to constrained the Object Definition with the
2418 -- expression constraints when it is unconstrained
2420 -- They must be generated in this order to avoid order of elaboration
2421 -- issues. Thus the first step (after entering the name) is to analyze
2422 -- the object definition.
2424 if Constant_Present (N) then
2425 Prev_Entity := Current_Entity_In_Scope (Id);
2427 if Present (Prev_Entity)
2429 -- If the homograph is an implicit subprogram, it is overridden
2430 -- by the current declaration.
2432 ((Is_Overloadable (Prev_Entity)
2433 and then Is_Inherited_Operation (Prev_Entity))
2435 -- The current object is a discriminal generated for an entry
2436 -- family index. Even though the index is a constant, in this
2437 -- particular context there is no true constant redeclaration.
2438 -- Enter_Name will handle the visibility.
2441 (Is_Discriminal (Id)
2442 and then Ekind (Discriminal_Link (Id)) =
2443 E_Entry_Index_Parameter)
2445 -- The current object is the renaming for a generic declared
2446 -- within the instance.
2449 (Ekind (Prev_Entity) = E_Package
2450 and then Nkind (Parent (Prev_Entity)) =
2451 N_Package_Renaming_Declaration
2452 and then not Comes_From_Source (Prev_Entity)
2453 and then Is_Generic_Instance (Renamed_Entity (Prev_Entity))))
2455 Prev_Entity := Empty;
2459 if Present (Prev_Entity) then
2460 Constant_Redeclaration (Id, N, T);
2462 Generate_Reference (Prev_Entity, Id, 'c');
2463 Set_Completion_Referenced (Id);
2465 if Error_Posted (N) then
2467 -- Type mismatch or illegal redeclaration, Do not analyze
2468 -- expression to avoid cascaded errors.
2470 T := Find_Type_Of_Object (Object_Definition (N), N);
2472 Set_Ekind (Id, E_Variable);
2476 -- In the normal case, enter identifier at the start to catch premature
2477 -- usage in the initialization expression.
2480 Generate_Definition (Id);
2483 Mark_Coextensions (N, Object_Definition (N));
2485 T := Find_Type_Of_Object (Object_Definition (N), N);
2487 if Nkind (Object_Definition (N)) = N_Access_Definition
2489 (Access_To_Subprogram_Definition (Object_Definition (N)))
2490 and then Protected_Present
2491 (Access_To_Subprogram_Definition (Object_Definition (N)))
2493 T := Replace_Anonymous_Access_To_Protected_Subprogram (N);
2496 if Error_Posted (Id) then
2498 Set_Ekind (Id, E_Variable);
2503 -- Ada 2005 (AI-231): Propagate the null-excluding attribute and carry
2504 -- out some static checks
2506 if Ada_Version >= Ada_05
2507 and then Can_Never_Be_Null (T)
2509 -- In case of aggregates we must also take care of the correct
2510 -- initialization of nested aggregates bug this is done at the
2511 -- point of the analysis of the aggregate (see sem_aggr.adb)
2513 if Present (Expression (N))
2514 and then Nkind (Expression (N)) = N_Aggregate
2520 Save_Typ : constant Entity_Id := Etype (Id);
2522 Set_Etype (Id, T); -- Temp. decoration for static checks
2523 Null_Exclusion_Static_Checks (N);
2524 Set_Etype (Id, Save_Typ);
2529 Set_Is_Pure (Id, Is_Pure (Current_Scope));
2531 -- If deferred constant, make sure context is appropriate. We detect
2532 -- a deferred constant as a constant declaration with no expression.
2533 -- A deferred constant can appear in a package body if its completion
2534 -- is by means of an interface pragma.
2536 if Constant_Present (N)
2539 -- A deferred constant may appear in the declarative part of the
2540 -- following constructs:
2544 -- extended return statements
2547 -- subprogram bodies
2550 -- When declared inside a package spec, a deferred constant must be
2551 -- completed by a full constant declaration or pragma Import. In all
2552 -- other cases, the only proper completion is pragma Import. Extended
2553 -- return statements are flagged as invalid contexts because they do
2554 -- not have a declarative part and so cannot accommodate the pragma.
2556 if Ekind (Current_Scope) = E_Return_Statement then
2558 ("invalid context for deferred constant declaration (RM 7.4)",
2561 ("\declaration requires an initialization expression",
2563 Set_Constant_Present (N, False);
2565 -- In Ada 83, deferred constant must be of private type
2567 elsif not Is_Private_Type (T) then
2568 if Ada_Version = Ada_83 and then Comes_From_Source (N) then
2570 ("(Ada 83) deferred constant must be private type", N);
2574 -- If not a deferred constant, then object declaration freezes its type
2577 Check_Fully_Declared (T, N);
2578 Freeze_Before (N, T);
2581 -- If the object was created by a constrained array definition, then
2582 -- set the link in both the anonymous base type and anonymous subtype
2583 -- that are built to represent the array type to point to the object.
2585 if Nkind (Object_Definition (Declaration_Node (Id))) =
2586 N_Constrained_Array_Definition
2588 Set_Related_Array_Object (T, Id);
2589 Set_Related_Array_Object (Base_Type (T), Id);
2592 -- Special checks for protected objects not at library level
2594 if Is_Protected_Type (T)
2595 and then not Is_Library_Level_Entity (Id)
2597 Check_Restriction (No_Local_Protected_Objects, Id);
2599 -- Protected objects with interrupt handlers must be at library level
2601 -- Ada 2005: this test is not needed (and the corresponding clause
2602 -- in the RM is removed) because accessibility checks are sufficient
2603 -- to make handlers not at the library level illegal.
2605 if Has_Interrupt_Handler (T)
2606 and then Ada_Version < Ada_05
2609 ("interrupt object can only be declared at library level", Id);
2613 -- The actual subtype of the object is the nominal subtype, unless
2614 -- the nominal one is unconstrained and obtained from the expression.
2618 -- Process initialization expression if present and not in error
2620 if Present (E) and then E /= Error then
2622 -- Generate an error in case of CPP class-wide object initialization.
2623 -- Required because otherwise the expansion of the class-wide
2624 -- assignment would try to use 'size to initialize the object
2625 -- (primitive that is not available in CPP tagged types).
2627 if Is_Class_Wide_Type (Act_T)
2629 (Is_CPP_Class (Root_Type (Etype (Act_T)))
2631 (Present (Full_View (Root_Type (Etype (Act_T))))
2633 Is_CPP_Class (Full_View (Root_Type (Etype (Act_T))))))
2636 ("predefined assignment not available for 'C'P'P tagged types",
2640 Mark_Coextensions (N, E);
2643 -- In case of errors detected in the analysis of the expression,
2644 -- decorate it with the expected type to avoid cascaded errors
2646 if No (Etype (E)) then
2650 -- If an initialization expression is present, then we set the
2651 -- Is_True_Constant flag. It will be reset if this is a variable
2652 -- and it is indeed modified.
2654 Set_Is_True_Constant (Id, True);
2656 -- If we are analyzing a constant declaration, set its completion
2657 -- flag after analyzing and resolving the expression.
2659 if Constant_Present (N) then
2660 Set_Has_Completion (Id);
2663 -- Set type and resolve (type may be overridden later on)
2668 -- If E is null and has been replaced by an N_Raise_Constraint_Error
2669 -- node (which was marked already-analyzed), we need to set the type
2670 -- to something other than Any_Access in order to keep gigi happy.
2672 if Etype (E) = Any_Access then
2676 -- If the object is an access to variable, the initialization
2677 -- expression cannot be an access to constant.
2679 if Is_Access_Type (T)
2680 and then not Is_Access_Constant (T)
2681 and then Is_Access_Type (Etype (E))
2682 and then Is_Access_Constant (Etype (E))
2685 ("access to variable cannot be initialized "
2686 & "with an access-to-constant expression", E);
2689 if not Assignment_OK (N) then
2690 Check_Initialization (T, E);
2693 Check_Unset_Reference (E);
2695 -- If this is a variable, then set current value. If this is a
2696 -- declared constant of a scalar type with a static expression,
2697 -- indicate that it is always valid.
2699 if not Constant_Present (N) then
2700 if Compile_Time_Known_Value (E) then
2701 Set_Current_Value (Id, E);
2704 elsif Is_Scalar_Type (T)
2705 and then Is_OK_Static_Expression (E)
2707 Set_Is_Known_Valid (Id);
2710 -- Deal with setting of null flags
2712 if Is_Access_Type (T) then
2713 if Known_Non_Null (E) then
2714 Set_Is_Known_Non_Null (Id, True);
2715 elsif Known_Null (E)
2716 and then not Can_Never_Be_Null (Id)
2718 Set_Is_Known_Null (Id, True);
2722 -- Check incorrect use of dynamically tagged expressions.
2724 if Is_Tagged_Type (T) then
2725 Check_Dynamically_Tagged_Expression
2731 Apply_Scalar_Range_Check (E, T);
2732 Apply_Static_Length_Check (E, T);
2735 -- If the No_Streams restriction is set, check that the type of the
2736 -- object is not, and does not contain, any subtype derived from
2737 -- Ada.Streams.Root_Stream_Type. Note that we guard the call to
2738 -- Has_Stream just for efficiency reasons. There is no point in
2739 -- spending time on a Has_Stream check if the restriction is not set.
2741 if Restrictions.Set (No_Streams) then
2742 if Has_Stream (T) then
2743 Check_Restriction (No_Streams, N);
2747 -- Case of unconstrained type
2749 if Is_Indefinite_Subtype (T) then
2751 -- Nothing to do in deferred constant case
2753 if Constant_Present (N) and then No (E) then
2756 -- Case of no initialization present
2759 if No_Initialization (N) then
2762 elsif Is_Class_Wide_Type (T) then
2764 ("initialization required in class-wide declaration ", N);
2768 ("unconstrained subtype not allowed (need initialization)",
2769 Object_Definition (N));
2771 if Is_Record_Type (T) and then Has_Discriminants (T) then
2773 ("\provide initial value or explicit discriminant values",
2774 Object_Definition (N));
2777 ("\or give default discriminant values for type&",
2778 Object_Definition (N), T);
2780 elsif Is_Array_Type (T) then
2782 ("\provide initial value or explicit array bounds",
2783 Object_Definition (N));
2787 -- Case of initialization present but in error. Set initial
2788 -- expression as absent (but do not make above complaints)
2790 elsif E = Error then
2791 Set_Expression (N, Empty);
2794 -- Case of initialization present
2797 -- Not allowed in Ada 83
2799 if not Constant_Present (N) then
2800 if Ada_Version = Ada_83
2801 and then Comes_From_Source (Object_Definition (N))
2804 ("(Ada 83) unconstrained variable not allowed",
2805 Object_Definition (N));
2809 -- Now we constrain the variable from the initializing expression
2811 -- If the expression is an aggregate, it has been expanded into
2812 -- individual assignments. Retrieve the actual type from the
2813 -- expanded construct.
2815 if Is_Array_Type (T)
2816 and then No_Initialization (N)
2817 and then Nkind (Original_Node (E)) = N_Aggregate
2821 -- In case of class-wide interface object declarations we delay
2822 -- the generation of the equivalent record type declarations until
2823 -- its expansion because there are cases in they are not required.
2825 elsif Is_Interface (T) then
2829 Expand_Subtype_From_Expr (N, T, Object_Definition (N), E);
2830 Act_T := Find_Type_Of_Object (Object_Definition (N), N);
2833 Set_Is_Constr_Subt_For_U_Nominal (Act_T);
2835 if Aliased_Present (N) then
2836 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
2839 Freeze_Before (N, Act_T);
2840 Freeze_Before (N, T);
2843 elsif Is_Array_Type (T)
2844 and then No_Initialization (N)
2845 and then Nkind (Original_Node (E)) = N_Aggregate
2847 if not Is_Entity_Name (Object_Definition (N)) then
2849 Check_Compile_Time_Size (Act_T);
2851 if Aliased_Present (N) then
2852 Set_Is_Constr_Subt_For_UN_Aliased (Act_T);
2856 -- When the given object definition and the aggregate are specified
2857 -- independently, and their lengths might differ do a length check.
2858 -- This cannot happen if the aggregate is of the form (others =>...)
2860 if not Is_Constrained (T) then
2863 elsif Nkind (E) = N_Raise_Constraint_Error then
2865 -- Aggregate is statically illegal. Place back in declaration
2867 Set_Expression (N, E);
2868 Set_No_Initialization (N, False);
2870 elsif T = Etype (E) then
2873 elsif Nkind (E) = N_Aggregate
2874 and then Present (Component_Associations (E))
2875 and then Present (Choices (First (Component_Associations (E))))
2876 and then Nkind (First
2877 (Choices (First (Component_Associations (E))))) = N_Others_Choice
2882 Apply_Length_Check (E, T);
2885 -- If the type is limited unconstrained with defaulted discriminants and
2886 -- there is no expression, then the object is constrained by the
2887 -- defaults, so it is worthwhile building the corresponding subtype.
2889 elsif (Is_Limited_Record (T) or else Is_Concurrent_Type (T))
2890 and then not Is_Constrained (T)
2891 and then Has_Discriminants (T)
2894 Act_T := Build_Default_Subtype (T, N);
2896 -- Ada 2005: a limited object may be initialized by means of an
2897 -- aggregate. If the type has default discriminants it has an
2898 -- unconstrained nominal type, Its actual subtype will be obtained
2899 -- from the aggregate, and not from the default discriminants.
2904 Rewrite (Object_Definition (N), New_Occurrence_Of (Act_T, Loc));
2906 elsif Present (Underlying_Type (T))
2907 and then not Is_Constrained (Underlying_Type (T))
2908 and then Has_Discriminants (Underlying_Type (T))
2909 and then Nkind (E) = N_Function_Call
2910 and then Constant_Present (N)
2912 -- The back-end has problems with constants of a discriminated type
2913 -- with defaults, if the initial value is a function call. We
2914 -- generate an intermediate temporary for the result of the call.
2915 -- It is unclear why this should make it acceptable to gcc. ???
2917 Remove_Side_Effects (E);
2920 -- Check No_Wide_Characters restriction
2922 if T = Standard_Wide_Character
2923 or else T = Standard_Wide_Wide_Character
2924 or else Root_Type (T) = Standard_Wide_String
2925 or else Root_Type (T) = Standard_Wide_Wide_String
2927 Check_Restriction (No_Wide_Characters, Object_Definition (N));
2930 -- Indicate this is not set in source. Certainly true for constants,
2931 -- and true for variables so far (will be reset for a variable if and
2932 -- when we encounter a modification in the source).
2934 Set_Never_Set_In_Source (Id, True);
2936 -- Now establish the proper kind and type of the object
2938 if Constant_Present (N) then
2939 Set_Ekind (Id, E_Constant);
2940 Set_Is_True_Constant (Id, True);
2943 Set_Ekind (Id, E_Variable);
2945 -- A variable is set as shared passive if it appears in a shared
2946 -- passive package, and is at the outer level. This is not done
2947 -- for entities generated during expansion, because those are
2948 -- always manipulated locally.
2950 if Is_Shared_Passive (Current_Scope)
2951 and then Is_Library_Level_Entity (Id)
2952 and then Comes_From_Source (Id)
2954 Set_Is_Shared_Passive (Id);
2955 Check_Shared_Var (Id, T, N);
2958 -- Set Has_Initial_Value if initializing expression present. Note
2959 -- that if there is no initializing expression, we leave the state
2960 -- of this flag unchanged (usually it will be False, but notably in
2961 -- the case of exception choice variables, it will already be true).
2964 Set_Has_Initial_Value (Id, True);
2968 -- Initialize alignment and size and capture alignment setting
2970 Init_Alignment (Id);
2972 Set_Optimize_Alignment_Flags (Id);
2974 -- Deal with aliased case
2976 if Aliased_Present (N) then
2977 Set_Is_Aliased (Id);
2979 -- If the object is aliased and the type is unconstrained with
2980 -- defaulted discriminants and there is no expression, then the
2981 -- object is constrained by the defaults, so it is worthwhile
2982 -- building the corresponding subtype.
2984 -- Ada 2005 (AI-363): If the aliased object is discriminated and
2985 -- unconstrained, then only establish an actual subtype if the
2986 -- nominal subtype is indefinite. In definite cases the object is
2987 -- unconstrained in Ada 2005.
2990 and then Is_Record_Type (T)
2991 and then not Is_Constrained (T)
2992 and then Has_Discriminants (T)
2993 and then (Ada_Version < Ada_05 or else Is_Indefinite_Subtype (T))
2995 Set_Actual_Subtype (Id, Build_Default_Subtype (T, N));
2999 -- Now we can set the type of the object
3001 Set_Etype (Id, Act_T);
3003 -- Deal with controlled types
3005 if Has_Controlled_Component (Etype (Id))
3006 or else Is_Controlled (Etype (Id))
3008 if not Is_Library_Level_Entity (Id) then
3009 Check_Restriction (No_Nested_Finalization, N);
3011 Validate_Controlled_Object (Id);
3014 -- Generate a warning when an initialization causes an obvious ABE
3015 -- violation. If the init expression is a simple aggregate there
3016 -- shouldn't be any initialize/adjust call generated. This will be
3017 -- true as soon as aggregates are built in place when possible.
3019 -- ??? at the moment we do not generate warnings for temporaries
3020 -- created for those aggregates although Program_Error might be
3021 -- generated if compiled with -gnato.
3023 if Is_Controlled (Etype (Id))
3024 and then Comes_From_Source (Id)
3027 BT : constant Entity_Id := Base_Type (Etype (Id));
3029 Implicit_Call : Entity_Id;
3030 pragma Warnings (Off, Implicit_Call);
3031 -- ??? what is this for (never referenced!)
3033 function Is_Aggr (N : Node_Id) return Boolean;
3034 -- Check that N is an aggregate
3040 function Is_Aggr (N : Node_Id) return Boolean is
3042 case Nkind (Original_Node (N)) is
3043 when N_Aggregate | N_Extension_Aggregate =>
3046 when N_Qualified_Expression |
3048 N_Unchecked_Type_Conversion =>
3049 return Is_Aggr (Expression (Original_Node (N)));
3057 -- If no underlying type, we already are in an error situation.
3058 -- Do not try to add a warning since we do not have access to
3061 if No (Underlying_Type (BT)) then
3062 Implicit_Call := Empty;
3064 -- A generic type does not have usable primitive operators.
3065 -- Initialization calls are built for instances.
3067 elsif Is_Generic_Type (BT) then
3068 Implicit_Call := Empty;
3070 -- If the init expression is not an aggregate, an adjust call
3071 -- will be generated
3073 elsif Present (E) and then not Is_Aggr (E) then
3074 Implicit_Call := Find_Prim_Op (BT, Name_Adjust);
3076 -- If no init expression and we are not in the deferred
3077 -- constant case, an Initialize call will be generated
3079 elsif No (E) and then not Constant_Present (N) then
3080 Implicit_Call := Find_Prim_Op (BT, Name_Initialize);
3083 Implicit_Call := Empty;
3089 if Has_Task (Etype (Id)) then
3090 Check_Restriction (No_Tasking, N);
3092 -- Deal with counting max tasks
3094 -- Nothing to do if inside a generic
3096 if Inside_A_Generic then
3099 -- If library level entity, then count tasks
3101 elsif Is_Library_Level_Entity (Id) then
3102 Check_Restriction (Max_Tasks, N, Count_Tasks (Etype (Id)));
3104 -- If not library level entity, then indicate we don't know max
3105 -- tasks and also check task hierarchy restriction and blocking
3106 -- operation (since starting a task is definitely blocking!)
3109 Check_Restriction (Max_Tasks, N);
3110 Check_Restriction (No_Task_Hierarchy, N);
3111 Check_Potentially_Blocking_Operation (N);
3114 -- A rather specialized test. If we see two tasks being declared
3115 -- of the same type in the same object declaration, and the task
3116 -- has an entry with an address clause, we know that program error
3117 -- will be raised at run-time since we can't have two tasks with
3118 -- entries at the same address.
3120 if Is_Task_Type (Etype (Id)) and then More_Ids (N) then
3125 E := First_Entity (Etype (Id));
3126 while Present (E) loop
3127 if Ekind (E) = E_Entry
3128 and then Present (Get_Attribute_Definition_Clause
3129 (E, Attribute_Address))
3132 ("?more than one task with same entry address", N);
3134 ("\?Program_Error will be raised at run time", N);
3136 Make_Raise_Program_Error (Loc,
3137 Reason => PE_Duplicated_Entry_Address));
3147 -- Some simple constant-propagation: if the expression is a constant
3148 -- string initialized with a literal, share the literal. This avoids
3152 and then Is_Entity_Name (E)
3153 and then Ekind (Entity (E)) = E_Constant
3154 and then Base_Type (Etype (E)) = Standard_String
3157 Val : constant Node_Id := Constant_Value (Entity (E));
3160 and then Nkind (Val) = N_String_Literal
3162 Rewrite (E, New_Copy (Val));
3167 -- Another optimization: if the nominal subtype is unconstrained and
3168 -- the expression is a function call that returns an unconstrained
3169 -- type, rewrite the declaration as a renaming of the result of the
3170 -- call. The exceptions below are cases where the copy is expected,
3171 -- either by the back end (Aliased case) or by the semantics, as for
3172 -- initializing controlled types or copying tags for classwide types.
3175 and then Nkind (E) = N_Explicit_Dereference
3176 and then Nkind (Original_Node (E)) = N_Function_Call
3177 and then not Is_Library_Level_Entity (Id)
3178 and then not Is_Constrained (Underlying_Type (T))
3179 and then not Is_Aliased (Id)
3180 and then not Is_Class_Wide_Type (T)
3181 and then not Is_Controlled (T)
3182 and then not Has_Controlled_Component (Base_Type (T))
3183 and then Expander_Active
3186 Make_Object_Renaming_Declaration (Loc,
3187 Defining_Identifier => Id,
3188 Access_Definition => Empty,
3189 Subtype_Mark => New_Occurrence_Of
3190 (Base_Type (Etype (Id)), Loc),
3193 Set_Renamed_Object (Id, E);
3195 -- Force generation of debugging information for the constant and for
3196 -- the renamed function call.
3198 Set_Debug_Info_Needed (Id);
3199 Set_Debug_Info_Needed (Entity (Prefix (E)));
3202 if Present (Prev_Entity)
3203 and then Is_Frozen (Prev_Entity)
3204 and then not Error_Posted (Id)
3206 Error_Msg_N ("full constant declaration appears too late", N);
3209 Check_Eliminated (Id);
3211 -- Deal with setting In_Private_Part flag if in private part
3213 if Ekind (Scope (Id)) = E_Package
3214 and then In_Private_Part (Scope (Id))
3216 Set_In_Private_Part (Id);
3219 -- Check for violation of No_Local_Timing_Events
3221 if Is_RTE (Etype (Id), RE_Timing_Event)
3222 and then not Is_Library_Level_Entity (Id)
3224 Check_Restriction (No_Local_Timing_Events, N);
3226 end Analyze_Object_Declaration;
3228 ---------------------------
3229 -- Analyze_Others_Choice --
3230 ---------------------------
3232 -- Nothing to do for the others choice node itself, the semantic analysis
3233 -- of the others choice will occur as part of the processing of the parent
3235 procedure Analyze_Others_Choice (N : Node_Id) is
3236 pragma Warnings (Off, N);
3239 end Analyze_Others_Choice;
3241 -------------------------------------------
3242 -- Analyze_Private_Extension_Declaration --
3243 -------------------------------------------
3245 procedure Analyze_Private_Extension_Declaration (N : Node_Id) is
3246 T : constant Entity_Id := Defining_Identifier (N);
3247 Indic : constant Node_Id := Subtype_Indication (N);
3248 Parent_Type : Entity_Id;
3249 Parent_Base : Entity_Id;
3252 -- Ada 2005 (AI-251): Decorate all names in list of ancestor interfaces
3254 if Is_Non_Empty_List (Interface_List (N)) then
3260 Intf := First (Interface_List (N));
3261 while Present (Intf) loop
3262 T := Find_Type_Of_Subtype_Indic (Intf);
3264 Diagnose_Interface (Intf, T);
3270 Generate_Definition (T);
3273 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
3274 Parent_Base := Base_Type (Parent_Type);
3276 if Parent_Type = Any_Type
3277 or else Etype (Parent_Type) = Any_Type
3279 Set_Ekind (T, Ekind (Parent_Type));
3280 Set_Etype (T, Any_Type);
3283 elsif not Is_Tagged_Type (Parent_Type) then
3285 ("parent of type extension must be a tagged type ", Indic);
3288 elsif Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
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);
7358 -- If the derived type is the anonymous type created for
7359 -- a declaration whose parent has a constraint, propagate
7360 -- the interface list to the source type. This must be done
7361 -- prior to the completion of the analysis of the source type
7362 -- because the components in the extension may contain current
7363 -- instances whose legality depends on some ancestor.
7365 if Is_Itype (Derived_Type) then
7367 Def : constant Node_Id :=
7368 Associated_Node_For_Itype (Derived_Type);
7371 and then Nkind (Def) = N_Full_Type_Declaration
7374 (Defining_Identifier (Def), Ifaces_List);
7382 Set_Is_Packed (Derived_Type, Is_Packed (Parent_Base));
7383 Set_Has_Non_Standard_Rep
7384 (Derived_Type, Has_Non_Standard_Rep (Parent_Base));
7387 -- STEP 4: Inherit components from the parent base and constrain them.
7388 -- Apply the second transformation described in point 6. above.
7390 if (not Is_Empty_Elmt_List (Discs) or else Inherit_Discrims)
7391 or else not Has_Discriminants (Parent_Type)
7392 or else not Is_Constrained (Parent_Type)
7396 Constrs := Discriminant_Constraint (Parent_Type);
7401 (N, Parent_Base, Derived_Type, Is_Tagged, Inherit_Discrims, Constrs);
7403 -- STEP 5a: Copy the parent record declaration for untagged types
7405 if not Is_Tagged then
7407 -- Discriminant_Constraint (Derived_Type) has been properly
7408 -- constructed. Save it and temporarily set it to Empty because we
7409 -- do not want the call to New_Copy_Tree below to mess this list.
7411 if Has_Discriminants (Derived_Type) then
7412 Save_Discr_Constr := Discriminant_Constraint (Derived_Type);
7413 Set_Discriminant_Constraint (Derived_Type, No_Elist);
7415 Save_Discr_Constr := No_Elist;
7418 -- Save the Etype field of Derived_Type. It is correctly set now,
7419 -- but the call to New_Copy tree may remap it to point to itself,
7420 -- which is not what we want. Ditto for the Next_Entity field.
7422 Save_Etype := Etype (Derived_Type);
7423 Save_Next_Entity := Next_Entity (Derived_Type);
7425 -- Assoc_List maps all stored discriminants in the Parent_Base to
7426 -- stored discriminants in the Derived_Type. It is fundamental that
7427 -- no types or itypes with discriminants other than the stored
7428 -- discriminants appear in the entities declared inside
7429 -- Derived_Type, since the back end cannot deal with it.
7433 (Parent (Parent_Base), Map => Assoc_List, New_Sloc => Loc);
7435 -- Restore the fields saved prior to the New_Copy_Tree call
7436 -- and compute the stored constraint.
7438 Set_Etype (Derived_Type, Save_Etype);
7439 Set_Next_Entity (Derived_Type, Save_Next_Entity);
7441 if Has_Discriminants (Derived_Type) then
7442 Set_Discriminant_Constraint
7443 (Derived_Type, Save_Discr_Constr);
7444 Set_Stored_Constraint
7445 (Derived_Type, Expand_To_Stored_Constraint (Parent_Type, Discs));
7446 Replace_Components (Derived_Type, New_Decl);
7449 -- Insert the new derived type declaration
7451 Rewrite (N, New_Decl);
7453 -- STEP 5b: Complete the processing for record extensions in generics
7455 -- There is no completion for record extensions declared in the
7456 -- parameter part of a generic, so we need to complete processing for
7457 -- these generic record extensions here. The Record_Type_Definition call
7458 -- will change the Ekind of the components from E_Void to E_Component.
7460 elsif Private_Extension and then Is_Generic_Type (Derived_Type) then
7461 Record_Type_Definition (Empty, Derived_Type);
7463 -- STEP 5c: Process the record extension for non private tagged types
7465 elsif not Private_Extension then
7467 -- Add the _parent field in the derived type
7469 Expand_Record_Extension (Derived_Type, Type_Def);
7471 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
7472 -- implemented interfaces if we are in expansion mode
7475 and then Has_Interfaces (Derived_Type)
7477 Add_Interface_Tag_Components (N, Derived_Type);
7480 -- Analyze the record extension
7482 Record_Type_Definition
7483 (Record_Extension_Part (Type_Def), Derived_Type);
7488 -- Nothing else to do if there is an error in the derivation.
7489 -- An unusual case: the full view may be derived from a type in an
7490 -- instance, when the partial view was used illegally as an actual
7491 -- in that instance, leading to a circular definition.
7493 if Etype (Derived_Type) = Any_Type
7494 or else Etype (Parent_Type) = Derived_Type
7499 -- Set delayed freeze and then derive subprograms, we need to do
7500 -- this in this order so that derived subprograms inherit the
7501 -- derived freeze if necessary.
7503 Set_Has_Delayed_Freeze (Derived_Type);
7505 if Derive_Subps then
7506 Derive_Subprograms (Parent_Type, Derived_Type);
7509 -- If we have a private extension which defines a constrained derived
7510 -- type mark as constrained here after we have derived subprograms. See
7511 -- comment on point 9. just above the body of Build_Derived_Record_Type.
7513 if Private_Extension and then Inherit_Discrims then
7514 if Constraint_Present and then not Is_Empty_Elmt_List (Discs) then
7515 Set_Is_Constrained (Derived_Type, True);
7516 Set_Discriminant_Constraint (Derived_Type, Discs);
7518 elsif Is_Constrained (Parent_Type) then
7520 (Derived_Type, True);
7521 Set_Discriminant_Constraint
7522 (Derived_Type, Discriminant_Constraint (Parent_Type));
7526 -- Update the class-wide type, which shares the now-completed entity
7527 -- list with its specific type. In case of underlying record views,
7528 -- we do not generate the corresponding class wide entity.
7531 and then not Is_Underlying_Record_View (Derived_Type)
7534 (Class_Wide_Type (Derived_Type), First_Entity (Derived_Type));
7536 (Class_Wide_Type (Derived_Type), Last_Entity (Derived_Type));
7539 -- Update the scope of anonymous access types of discriminants and other
7540 -- components, to prevent scope anomalies in gigi, when the derivation
7541 -- appears in a scope nested within that of the parent.
7547 D := First_Entity (Derived_Type);
7548 while Present (D) loop
7549 if Ekind_In (D, E_Discriminant, E_Component) then
7550 if Is_Itype (Etype (D))
7551 and then Ekind (Etype (D)) = E_Anonymous_Access_Type
7553 Set_Scope (Etype (D), Current_Scope);
7560 end Build_Derived_Record_Type;
7562 ------------------------
7563 -- Build_Derived_Type --
7564 ------------------------
7566 procedure Build_Derived_Type
7568 Parent_Type : Entity_Id;
7569 Derived_Type : Entity_Id;
7570 Is_Completion : Boolean;
7571 Derive_Subps : Boolean := True)
7573 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
7576 -- Set common attributes
7578 Set_Scope (Derived_Type, Current_Scope);
7580 Set_Ekind (Derived_Type, Ekind (Parent_Base));
7581 Set_Etype (Derived_Type, Parent_Base);
7582 Set_Has_Task (Derived_Type, Has_Task (Parent_Base));
7584 Set_Size_Info (Derived_Type, Parent_Type);
7585 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
7586 Set_Convention (Derived_Type, Convention (Parent_Type));
7587 Set_Is_Controlled (Derived_Type, Is_Controlled (Parent_Type));
7588 Set_Is_Tagged_Type (Derived_Type, Is_Tagged_Type (Parent_Type));
7590 -- The derived type inherits the representation clauses of the parent.
7591 -- However, for a private type that is completed by a derivation, there
7592 -- may be operation attributes that have been specified already (stream
7593 -- attributes and External_Tag) and those must be provided. Finally,
7594 -- if the partial view is a private extension, the representation items
7595 -- of the parent have been inherited already, and should not be chained
7596 -- twice to the derived type.
7598 if Is_Tagged_Type (Parent_Type)
7599 and then Present (First_Rep_Item (Derived_Type))
7601 -- The existing items are either operational items or items inherited
7602 -- from a private extension declaration.
7606 -- Used to iterate over representation items of the derived type
7609 -- Last representation item of the (non-empty) representation
7610 -- item list of the derived type.
7612 Found : Boolean := False;
7615 Rep := First_Rep_Item (Derived_Type);
7617 while Present (Rep) loop
7618 if Rep = First_Rep_Item (Parent_Type) then
7623 Rep := Next_Rep_Item (Rep);
7625 if Present (Rep) then
7631 -- Here if we either encountered the parent type's first rep
7632 -- item on the derived type's rep item list (in which case
7633 -- Found is True, and we have nothing else to do), or if we
7634 -- reached the last rep item of the derived type, which is
7635 -- Last_Rep, in which case we further chain the parent type's
7636 -- rep items to those of the derived type.
7639 Set_Next_Rep_Item (Last_Rep, First_Rep_Item (Parent_Type));
7644 Set_First_Rep_Item (Derived_Type, First_Rep_Item (Parent_Type));
7647 case Ekind (Parent_Type) is
7648 when Numeric_Kind =>
7649 Build_Derived_Numeric_Type (N, Parent_Type, Derived_Type);
7652 Build_Derived_Array_Type (N, Parent_Type, Derived_Type);
7656 | Class_Wide_Kind =>
7657 Build_Derived_Record_Type
7658 (N, Parent_Type, Derived_Type, Derive_Subps);
7661 when Enumeration_Kind =>
7662 Build_Derived_Enumeration_Type (N, Parent_Type, Derived_Type);
7665 Build_Derived_Access_Type (N, Parent_Type, Derived_Type);
7667 when Incomplete_Or_Private_Kind =>
7668 Build_Derived_Private_Type
7669 (N, Parent_Type, Derived_Type, Is_Completion, Derive_Subps);
7671 -- For discriminated types, the derivation includes deriving
7672 -- primitive operations. For others it is done below.
7674 if Is_Tagged_Type (Parent_Type)
7675 or else Has_Discriminants (Parent_Type)
7676 or else (Present (Full_View (Parent_Type))
7677 and then Has_Discriminants (Full_View (Parent_Type)))
7682 when Concurrent_Kind =>
7683 Build_Derived_Concurrent_Type (N, Parent_Type, Derived_Type);
7686 raise Program_Error;
7689 if Etype (Derived_Type) = Any_Type then
7693 -- Set delayed freeze and then derive subprograms, we need to do this
7694 -- in this order so that derived subprograms inherit the derived freeze
7697 Set_Has_Delayed_Freeze (Derived_Type);
7698 if Derive_Subps then
7699 Derive_Subprograms (Parent_Type, Derived_Type);
7702 Set_Has_Primitive_Operations
7703 (Base_Type (Derived_Type), Has_Primitive_Operations (Parent_Type));
7704 end Build_Derived_Type;
7706 -----------------------
7707 -- Build_Discriminal --
7708 -----------------------
7710 procedure Build_Discriminal (Discrim : Entity_Id) is
7711 D_Minal : Entity_Id;
7712 CR_Disc : Entity_Id;
7715 -- A discriminal has the same name as the discriminant
7718 Make_Defining_Identifier (Sloc (Discrim),
7719 Chars => Chars (Discrim));
7721 Set_Ekind (D_Minal, E_In_Parameter);
7722 Set_Mechanism (D_Minal, Default_Mechanism);
7723 Set_Etype (D_Minal, Etype (Discrim));
7725 Set_Discriminal (Discrim, D_Minal);
7726 Set_Discriminal_Link (D_Minal, Discrim);
7728 -- For task types, build at once the discriminants of the corresponding
7729 -- record, which are needed if discriminants are used in entry defaults
7730 -- and in family bounds.
7732 if Is_Concurrent_Type (Current_Scope)
7733 or else Is_Limited_Type (Current_Scope)
7735 CR_Disc := Make_Defining_Identifier (Sloc (Discrim), Chars (Discrim));
7737 Set_Ekind (CR_Disc, E_In_Parameter);
7738 Set_Mechanism (CR_Disc, Default_Mechanism);
7739 Set_Etype (CR_Disc, Etype (Discrim));
7740 Set_Discriminal_Link (CR_Disc, Discrim);
7741 Set_CR_Discriminant (Discrim, CR_Disc);
7743 end Build_Discriminal;
7745 ------------------------------------
7746 -- Build_Discriminant_Constraints --
7747 ------------------------------------
7749 function Build_Discriminant_Constraints
7752 Derived_Def : Boolean := False) return Elist_Id
7754 C : constant Node_Id := Constraint (Def);
7755 Nb_Discr : constant Nat := Number_Discriminants (T);
7757 Discr_Expr : array (1 .. Nb_Discr) of Node_Id := (others => Empty);
7758 -- Saves the expression corresponding to a given discriminant in T
7760 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat;
7761 -- Return the Position number within array Discr_Expr of a discriminant
7762 -- D within the discriminant list of the discriminated type T.
7768 function Pos_Of_Discr (T : Entity_Id; D : Entity_Id) return Nat is
7772 Disc := First_Discriminant (T);
7773 for J in Discr_Expr'Range loop
7778 Next_Discriminant (Disc);
7781 -- Note: Since this function is called on discriminants that are
7782 -- known to belong to the discriminated type, falling through the
7783 -- loop with no match signals an internal compiler error.
7785 raise Program_Error;
7788 -- Declarations local to Build_Discriminant_Constraints
7792 Elist : constant Elist_Id := New_Elmt_List;
7800 Discrim_Present : Boolean := False;
7802 -- Start of processing for Build_Discriminant_Constraints
7805 -- The following loop will process positional associations only.
7806 -- For a positional association, the (single) discriminant is
7807 -- implicitly specified by position, in textual order (RM 3.7.2).
7809 Discr := First_Discriminant (T);
7810 Constr := First (Constraints (C));
7811 for D in Discr_Expr'Range loop
7812 exit when Nkind (Constr) = N_Discriminant_Association;
7815 Error_Msg_N ("too few discriminants given in constraint", C);
7816 return New_Elmt_List;
7818 elsif Nkind (Constr) = N_Range
7819 or else (Nkind (Constr) = N_Attribute_Reference
7821 Attribute_Name (Constr) = Name_Range)
7824 ("a range is not a valid discriminant constraint", Constr);
7825 Discr_Expr (D) := Error;
7828 Analyze_And_Resolve (Constr, Base_Type (Etype (Discr)));
7829 Discr_Expr (D) := Constr;
7832 Next_Discriminant (Discr);
7836 if No (Discr) and then Present (Constr) then
7837 Error_Msg_N ("too many discriminants given in constraint", Constr);
7838 return New_Elmt_List;
7841 -- Named associations can be given in any order, but if both positional
7842 -- and named associations are used in the same discriminant constraint,
7843 -- then positional associations must occur first, at their normal
7844 -- position. Hence once a named association is used, the rest of the
7845 -- discriminant constraint must use only named associations.
7847 while Present (Constr) loop
7849 -- Positional association forbidden after a named association
7851 if Nkind (Constr) /= N_Discriminant_Association then
7852 Error_Msg_N ("positional association follows named one", Constr);
7853 return New_Elmt_List;
7855 -- Otherwise it is a named association
7858 -- E records the type of the discriminants in the named
7859 -- association. All the discriminants specified in the same name
7860 -- association must have the same type.
7864 -- Search the list of discriminants in T to see if the simple name
7865 -- given in the constraint matches any of them.
7867 Id := First (Selector_Names (Constr));
7868 while Present (Id) loop
7871 -- If Original_Discriminant is present, we are processing a
7872 -- generic instantiation and this is an instance node. We need
7873 -- to find the name of the corresponding discriminant in the
7874 -- actual record type T and not the name of the discriminant in
7875 -- the generic formal. Example:
7878 -- type G (D : int) is private;
7880 -- subtype W is G (D => 1);
7882 -- type Rec (X : int) is record ... end record;
7883 -- package Q is new P (G => Rec);
7885 -- At the point of the instantiation, formal type G is Rec
7886 -- and therefore when reanalyzing "subtype W is G (D => 1);"
7887 -- which really looks like "subtype W is Rec (D => 1);" at
7888 -- the point of instantiation, we want to find the discriminant
7889 -- that corresponds to D in Rec, i.e. X.
7891 if Present (Original_Discriminant (Id)) then
7892 Discr := Find_Corresponding_Discriminant (Id, T);
7896 Discr := First_Discriminant (T);
7897 while Present (Discr) loop
7898 if Chars (Discr) = Chars (Id) then
7903 Next_Discriminant (Discr);
7907 Error_Msg_N ("& does not match any discriminant", Id);
7908 return New_Elmt_List;
7910 -- The following is only useful for the benefit of generic
7911 -- instances but it does not interfere with other
7912 -- processing for the non-generic case so we do it in all
7913 -- cases (for generics this statement is executed when
7914 -- processing the generic definition, see comment at the
7915 -- beginning of this if statement).
7918 Set_Original_Discriminant (Id, Discr);
7922 Position := Pos_Of_Discr (T, Discr);
7924 if Present (Discr_Expr (Position)) then
7925 Error_Msg_N ("duplicate constraint for discriminant&", Id);
7928 -- Each discriminant specified in the same named association
7929 -- must be associated with a separate copy of the
7930 -- corresponding expression.
7932 if Present (Next (Id)) then
7933 Expr := New_Copy_Tree (Expression (Constr));
7934 Set_Parent (Expr, Parent (Expression (Constr)));
7936 Expr := Expression (Constr);
7939 Discr_Expr (Position) := Expr;
7940 Analyze_And_Resolve (Expr, Base_Type (Etype (Discr)));
7943 -- A discriminant association with more than one discriminant
7944 -- name is only allowed if the named discriminants are all of
7945 -- the same type (RM 3.7.1(8)).
7948 E := Base_Type (Etype (Discr));
7950 elsif Base_Type (Etype (Discr)) /= E then
7952 ("all discriminants in an association " &
7953 "must have the same type", Id);
7963 -- A discriminant constraint must provide exactly one value for each
7964 -- discriminant of the type (RM 3.7.1(8)).
7966 for J in Discr_Expr'Range loop
7967 if No (Discr_Expr (J)) then
7968 Error_Msg_N ("too few discriminants given in constraint", C);
7969 return New_Elmt_List;
7973 -- Determine if there are discriminant expressions in the constraint
7975 for J in Discr_Expr'Range loop
7976 if Denotes_Discriminant
7977 (Discr_Expr (J), Check_Concurrent => True)
7979 Discrim_Present := True;
7983 -- Build an element list consisting of the expressions given in the
7984 -- discriminant constraint and apply the appropriate checks. The list
7985 -- is constructed after resolving any named discriminant associations
7986 -- and therefore the expressions appear in the textual order of the
7989 Discr := First_Discriminant (T);
7990 for J in Discr_Expr'Range loop
7991 if Discr_Expr (J) /= Error then
7992 Append_Elmt (Discr_Expr (J), Elist);
7994 -- If any of the discriminant constraints is given by a
7995 -- discriminant and we are in a derived type declaration we
7996 -- have a discriminant renaming. Establish link between new
7997 -- and old discriminant.
7999 if Denotes_Discriminant (Discr_Expr (J)) then
8001 Set_Corresponding_Discriminant
8002 (Entity (Discr_Expr (J)), Discr);
8005 -- Force the evaluation of non-discriminant expressions.
8006 -- If we have found a discriminant in the constraint 3.4(26)
8007 -- and 3.8(18) demand that no range checks are performed are
8008 -- after evaluation. If the constraint is for a component
8009 -- definition that has a per-object constraint, expressions are
8010 -- evaluated but not checked either. In all other cases perform
8014 if Discrim_Present then
8017 elsif Nkind (Parent (Parent (Def))) = N_Component_Declaration
8019 Has_Per_Object_Constraint
8020 (Defining_Identifier (Parent (Parent (Def))))
8024 elsif Is_Access_Type (Etype (Discr)) then
8025 Apply_Constraint_Check (Discr_Expr (J), Etype (Discr));
8028 Apply_Range_Check (Discr_Expr (J), Etype (Discr));
8031 Force_Evaluation (Discr_Expr (J));
8034 -- Check that the designated type of an access discriminant's
8035 -- expression is not a class-wide type unless the discriminant's
8036 -- designated type is also class-wide.
8038 if Ekind (Etype (Discr)) = E_Anonymous_Access_Type
8039 and then not Is_Class_Wide_Type
8040 (Designated_Type (Etype (Discr)))
8041 and then Etype (Discr_Expr (J)) /= Any_Type
8042 and then Is_Class_Wide_Type
8043 (Designated_Type (Etype (Discr_Expr (J))))
8045 Wrong_Type (Discr_Expr (J), Etype (Discr));
8047 elsif Is_Access_Type (Etype (Discr))
8048 and then not Is_Access_Constant (Etype (Discr))
8049 and then Is_Access_Type (Etype (Discr_Expr (J)))
8050 and then Is_Access_Constant (Etype (Discr_Expr (J)))
8053 ("constraint for discriminant& must be access to variable",
8058 Next_Discriminant (Discr);
8062 end Build_Discriminant_Constraints;
8064 ---------------------------------
8065 -- Build_Discriminated_Subtype --
8066 ---------------------------------
8068 procedure Build_Discriminated_Subtype
8072 Related_Nod : Node_Id;
8073 For_Access : Boolean := False)
8075 Has_Discrs : constant Boolean := Has_Discriminants (T);
8076 Constrained : constant Boolean :=
8078 and then not Is_Empty_Elmt_List (Elist)
8079 and then not Is_Class_Wide_Type (T))
8080 or else Is_Constrained (T);
8083 if Ekind (T) = E_Record_Type then
8085 Set_Ekind (Def_Id, E_Private_Subtype);
8086 Set_Is_For_Access_Subtype (Def_Id, True);
8088 Set_Ekind (Def_Id, E_Record_Subtype);
8091 -- Inherit preelaboration flag from base, for types for which it
8092 -- may have been set: records, private types, protected types.
8094 Set_Known_To_Have_Preelab_Init
8095 (Def_Id, Known_To_Have_Preelab_Init (T));
8097 elsif Ekind (T) = E_Task_Type then
8098 Set_Ekind (Def_Id, E_Task_Subtype);
8100 elsif Ekind (T) = E_Protected_Type then
8101 Set_Ekind (Def_Id, E_Protected_Subtype);
8102 Set_Known_To_Have_Preelab_Init
8103 (Def_Id, Known_To_Have_Preelab_Init (T));
8105 elsif Is_Private_Type (T) then
8106 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
8107 Set_Known_To_Have_Preelab_Init
8108 (Def_Id, Known_To_Have_Preelab_Init (T));
8110 elsif Is_Class_Wide_Type (T) then
8111 Set_Ekind (Def_Id, E_Class_Wide_Subtype);
8114 -- Incomplete type. Attach subtype to list of dependents, to be
8115 -- completed with full view of parent type, unless is it the
8116 -- designated subtype of a record component within an init_proc.
8117 -- This last case arises for a component of an access type whose
8118 -- designated type is incomplete (e.g. a Taft Amendment type).
8119 -- The designated subtype is within an inner scope, and needs no
8120 -- elaboration, because only the access type is needed in the
8121 -- initialization procedure.
8123 Set_Ekind (Def_Id, Ekind (T));
8125 if For_Access and then Within_Init_Proc then
8128 Append_Elmt (Def_Id, Private_Dependents (T));
8132 Set_Etype (Def_Id, T);
8133 Init_Size_Align (Def_Id);
8134 Set_Has_Discriminants (Def_Id, Has_Discrs);
8135 Set_Is_Constrained (Def_Id, Constrained);
8137 Set_First_Entity (Def_Id, First_Entity (T));
8138 Set_Last_Entity (Def_Id, Last_Entity (T));
8140 -- If the subtype is the completion of a private declaration, there may
8141 -- have been representation clauses for the partial view, and they must
8142 -- be preserved. Build_Derived_Type chains the inherited clauses with
8143 -- the ones appearing on the extension. If this comes from a subtype
8144 -- declaration, all clauses are inherited.
8146 if No (First_Rep_Item (Def_Id)) then
8147 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
8150 if Is_Tagged_Type (T) then
8151 Set_Is_Tagged_Type (Def_Id);
8152 Make_Class_Wide_Type (Def_Id);
8155 Set_Stored_Constraint (Def_Id, No_Elist);
8158 Set_Discriminant_Constraint (Def_Id, Elist);
8159 Set_Stored_Constraint_From_Discriminant_Constraint (Def_Id);
8162 if Is_Tagged_Type (T) then
8164 -- Ada 2005 (AI-251): In case of concurrent types we inherit the
8165 -- concurrent record type (which has the list of primitive
8168 if Ada_Version >= Ada_05
8169 and then Is_Concurrent_Type (T)
8171 Set_Corresponding_Record_Type (Def_Id,
8172 Corresponding_Record_Type (T));
8174 Set_Primitive_Operations (Def_Id, Primitive_Operations (T));
8177 Set_Is_Abstract_Type (Def_Id, Is_Abstract_Type (T));
8180 -- Subtypes introduced by component declarations do not need to be
8181 -- marked as delayed, and do not get freeze nodes, because the semantics
8182 -- verifies that the parents of the subtypes are frozen before the
8183 -- enclosing record is frozen.
8185 if not Is_Type (Scope (Def_Id)) then
8186 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
8188 if Is_Private_Type (T)
8189 and then Present (Full_View (T))
8191 Conditional_Delay (Def_Id, Full_View (T));
8193 Conditional_Delay (Def_Id, T);
8197 if Is_Record_Type (T) then
8198 Set_Is_Limited_Record (Def_Id, Is_Limited_Record (T));
8201 and then not Is_Empty_Elmt_List (Elist)
8202 and then not For_Access
8204 Create_Constrained_Components (Def_Id, Related_Nod, T, Elist);
8205 elsif not For_Access then
8206 Set_Cloned_Subtype (Def_Id, T);
8209 end Build_Discriminated_Subtype;
8211 ---------------------------
8212 -- Build_Itype_Reference --
8213 ---------------------------
8215 procedure Build_Itype_Reference
8219 IR : constant Node_Id := Make_Itype_Reference (Sloc (Nod));
8221 Set_Itype (IR, Ityp);
8222 Insert_After (Nod, IR);
8223 end Build_Itype_Reference;
8225 ------------------------
8226 -- Build_Scalar_Bound --
8227 ------------------------
8229 function Build_Scalar_Bound
8232 Der_T : Entity_Id) return Node_Id
8234 New_Bound : Entity_Id;
8237 -- Note: not clear why this is needed, how can the original bound
8238 -- be unanalyzed at this point? and if it is, what business do we
8239 -- have messing around with it? and why is the base type of the
8240 -- parent type the right type for the resolution. It probably is
8241 -- not! It is OK for the new bound we are creating, but not for
8242 -- the old one??? Still if it never happens, no problem!
8244 Analyze_And_Resolve (Bound, Base_Type (Par_T));
8246 if Nkind_In (Bound, N_Integer_Literal, N_Real_Literal) then
8247 New_Bound := New_Copy (Bound);
8248 Set_Etype (New_Bound, Der_T);
8249 Set_Analyzed (New_Bound);
8251 elsif Is_Entity_Name (Bound) then
8252 New_Bound := OK_Convert_To (Der_T, New_Copy (Bound));
8254 -- The following is almost certainly wrong. What business do we have
8255 -- relocating a node (Bound) that is presumably still attached to
8256 -- the tree elsewhere???
8259 New_Bound := OK_Convert_To (Der_T, Relocate_Node (Bound));
8262 Set_Etype (New_Bound, Der_T);
8264 end Build_Scalar_Bound;
8266 --------------------------------
8267 -- Build_Underlying_Full_View --
8268 --------------------------------
8270 procedure Build_Underlying_Full_View
8275 Loc : constant Source_Ptr := Sloc (N);
8276 Subt : constant Entity_Id :=
8277 Make_Defining_Identifier
8278 (Loc, New_External_Name (Chars (Typ), 'S'));
8285 procedure Set_Discriminant_Name (Id : Node_Id);
8286 -- If the derived type has discriminants, they may rename discriminants
8287 -- of the parent. When building the full view of the parent, we need to
8288 -- recover the names of the original discriminants if the constraint is
8289 -- given by named associations.
8291 ---------------------------
8292 -- Set_Discriminant_Name --
8293 ---------------------------
8295 procedure Set_Discriminant_Name (Id : Node_Id) is
8299 Set_Original_Discriminant (Id, Empty);
8301 if Has_Discriminants (Typ) then
8302 Disc := First_Discriminant (Typ);
8303 while Present (Disc) loop
8304 if Chars (Disc) = Chars (Id)
8305 and then Present (Corresponding_Discriminant (Disc))
8307 Set_Chars (Id, Chars (Corresponding_Discriminant (Disc)));
8309 Next_Discriminant (Disc);
8312 end Set_Discriminant_Name;
8314 -- Start of processing for Build_Underlying_Full_View
8317 if Nkind (N) = N_Full_Type_Declaration then
8318 Constr := Constraint (Subtype_Indication (Type_Definition (N)));
8320 elsif Nkind (N) = N_Subtype_Declaration then
8321 Constr := New_Copy_Tree (Constraint (Subtype_Indication (N)));
8323 elsif Nkind (N) = N_Component_Declaration then
8326 (Constraint (Subtype_Indication (Component_Definition (N))));
8329 raise Program_Error;
8332 C := First (Constraints (Constr));
8333 while Present (C) loop
8334 if Nkind (C) = N_Discriminant_Association then
8335 Id := First (Selector_Names (C));
8336 while Present (Id) loop
8337 Set_Discriminant_Name (Id);
8346 Make_Subtype_Declaration (Loc,
8347 Defining_Identifier => Subt,
8348 Subtype_Indication =>
8349 Make_Subtype_Indication (Loc,
8350 Subtype_Mark => New_Reference_To (Par, Loc),
8351 Constraint => New_Copy_Tree (Constr)));
8353 -- If this is a component subtype for an outer itype, it is not
8354 -- a list member, so simply set the parent link for analysis: if
8355 -- the enclosing type does not need to be in a declarative list,
8356 -- neither do the components.
8358 if Is_List_Member (N)
8359 and then Nkind (N) /= N_Component_Declaration
8361 Insert_Before (N, Indic);
8363 Set_Parent (Indic, Parent (N));
8367 Set_Underlying_Full_View (Typ, Full_View (Subt));
8368 end Build_Underlying_Full_View;
8370 -------------------------------
8371 -- Check_Abstract_Overriding --
8372 -------------------------------
8374 procedure Check_Abstract_Overriding (T : Entity_Id) is
8375 Alias_Subp : Entity_Id;
8382 Op_List := Primitive_Operations (T);
8384 -- Loop to check primitive operations
8386 Elmt := First_Elmt (Op_List);
8387 while Present (Elmt) loop
8388 Subp := Node (Elmt);
8389 Alias_Subp := Alias (Subp);
8391 -- Inherited subprograms are identified by the fact that they do not
8392 -- come from source, and the associated source location is the
8393 -- location of the first subtype of the derived type.
8395 -- Ada 2005 (AI-228): Apply the rules of RM-3.9.3(6/2) for
8396 -- subprograms that "require overriding".
8398 -- Special exception, do not complain about failure to override the
8399 -- stream routines _Input and _Output, as well as the primitive
8400 -- operations used in dispatching selects since we always provide
8401 -- automatic overridings for these subprograms.
8403 -- Also ignore this rule for convention CIL since .NET libraries
8404 -- do bizarre things with interfaces???
8406 -- The partial view of T may have been a private extension, for
8407 -- which inherited functions dispatching on result are abstract.
8408 -- If the full view is a null extension, there is no need for
8409 -- overriding in Ada2005, but wrappers need to be built for them
8410 -- (see exp_ch3, Build_Controlling_Function_Wrappers).
8412 if Is_Null_Extension (T)
8413 and then Has_Controlling_Result (Subp)
8414 and then Ada_Version >= Ada_05
8415 and then Present (Alias_Subp)
8416 and then not Comes_From_Source (Subp)
8417 and then not Is_Abstract_Subprogram (Alias_Subp)
8418 and then not Is_Access_Type (Etype (Subp))
8422 -- Ada 2005 (AI-251): Internal entities of interfaces need no
8423 -- processing because this check is done with the aliased
8426 elsif Present (Interface_Alias (Subp)) then
8429 elsif (Is_Abstract_Subprogram (Subp)
8430 or else Requires_Overriding (Subp)
8432 (Has_Controlling_Result (Subp)
8433 and then Present (Alias_Subp)
8434 and then not Comes_From_Source (Subp)
8435 and then Sloc (Subp) = Sloc (First_Subtype (T))))
8436 and then not Is_TSS (Subp, TSS_Stream_Input)
8437 and then not Is_TSS (Subp, TSS_Stream_Output)
8438 and then not Is_Abstract_Type (T)
8439 and then Convention (T) /= Convention_CIL
8440 and then not Is_Predefined_Interface_Primitive (Subp)
8442 -- Ada 2005 (AI-251): Do not consider hidden entities associated
8443 -- with abstract interface types because the check will be done
8444 -- with the aliased entity (otherwise we generate a duplicated
8447 and then not Present (Interface_Alias (Subp))
8449 if Present (Alias_Subp) then
8451 -- Only perform the check for a derived subprogram when the
8452 -- type has an explicit record extension. This avoids incorrect
8453 -- flagging of abstract subprograms for the case of a type
8454 -- without an extension that is derived from a formal type
8455 -- with a tagged actual (can occur within a private part).
8457 -- Ada 2005 (AI-391): In the case of an inherited function with
8458 -- a controlling result of the type, the rule does not apply if
8459 -- the type is a null extension (unless the parent function
8460 -- itself is abstract, in which case the function must still be
8461 -- be overridden). The expander will generate an overriding
8462 -- wrapper function calling the parent subprogram (see
8463 -- Exp_Ch3.Make_Controlling_Wrapper_Functions).
8465 Type_Def := Type_Definition (Parent (T));
8467 if Nkind (Type_Def) = N_Derived_Type_Definition
8468 and then Present (Record_Extension_Part (Type_Def))
8470 (Ada_Version < Ada_05
8471 or else not Is_Null_Extension (T)
8472 or else Ekind (Subp) = E_Procedure
8473 or else not Has_Controlling_Result (Subp)
8474 or else Is_Abstract_Subprogram (Alias_Subp)
8475 or else Requires_Overriding (Subp)
8476 or else Is_Access_Type (Etype (Subp)))
8478 -- Avoid reporting error in case of abstract predefined
8479 -- primitive inherited from interface type because the
8480 -- body of internally generated predefined primitives
8481 -- of tagged types are generated later by Freeze_Type
8483 if Is_Interface (Root_Type (T))
8484 and then Is_Abstract_Subprogram (Subp)
8485 and then Is_Predefined_Dispatching_Operation (Subp)
8486 and then not Comes_From_Source (Ultimate_Alias (Subp))
8492 ("type must be declared abstract or & overridden",
8495 -- Traverse the whole chain of aliased subprograms to
8496 -- complete the error notification. This is especially
8497 -- useful for traceability of the chain of entities when
8498 -- the subprogram corresponds with an interface
8499 -- subprogram (which may be defined in another package).
8501 if Present (Alias_Subp) then
8507 while Present (Alias (E)) loop
8508 Error_Msg_Sloc := Sloc (E);
8510 ("\& has been inherited #", T, Subp);
8514 Error_Msg_Sloc := Sloc (E);
8516 ("\& has been inherited from subprogram #",
8522 -- Ada 2005 (AI-345): Protected or task type implementing
8523 -- abstract interfaces.
8525 elsif Is_Concurrent_Record_Type (T)
8526 and then Present (Interfaces (T))
8528 -- The controlling formal of Subp must be of mode "out",
8529 -- "in out" or an access-to-variable to be overridden.
8531 -- Error message below needs rewording (remember comma
8532 -- in -gnatj mode) ???
8534 if Ekind (First_Formal (Subp)) = E_In_Parameter
8535 and then Ekind (Subp) /= E_Function
8537 if not Is_Predefined_Dispatching_Operation (Subp) then
8539 ("first formal of & must be of mode `OUT`, " &
8540 "`IN OUT` or access-to-variable", T, Subp);
8542 ("\to be overridden by protected procedure or " &
8543 "entry (RM 9.4(11.9/2))", T);
8546 -- Some other kind of overriding failure
8550 ("interface subprogram & must be overridden",
8553 -- Examine primitive operations of synchronized type,
8554 -- to find homonyms that have the wrong profile.
8561 First_Entity (Corresponding_Concurrent_Type (T));
8562 while Present (Prim) loop
8563 if Chars (Prim) = Chars (Subp) then
8565 ("profile is not type conformant with "
8566 & "prefixed view profile of "
8567 & "inherited operation&", Prim, Subp);
8577 Error_Msg_Node_2 := T;
8579 ("abstract subprogram& not allowed for type&", Subp);
8581 -- Also post unconditional warning on the type (unconditional
8582 -- so that if there are more than one of these cases, we get
8583 -- them all, and not just the first one).
8585 Error_Msg_Node_2 := Subp;
8587 ("nonabstract type& has abstract subprogram&!", T);
8591 -- Ada 2005 (AI05-0030): Inspect hidden subprograms which provide
8592 -- the mapping between interface and implementing type primitives.
8593 -- If the interface alias is marked as Implemented_By_Entry, the
8594 -- alias must be an entry wrapper.
8596 if Ada_Version >= Ada_05
8597 and then Is_Hidden (Subp)
8598 and then Present (Interface_Alias (Subp))
8599 and then Implemented_By_Entry (Interface_Alias (Subp))
8600 and then Present (Alias_Subp)
8602 (not Is_Primitive_Wrapper (Alias_Subp)
8603 or else Ekind (Wrapped_Entity (Alias_Subp)) /= E_Entry)
8606 Error_Ent : Entity_Id := T;
8609 if Is_Concurrent_Record_Type (Error_Ent) then
8610 Error_Ent := Corresponding_Concurrent_Type (Error_Ent);
8613 Error_Msg_Node_2 := Interface_Alias (Subp);
8615 ("type & must implement abstract subprogram & with an entry",
8616 Error_Ent, Error_Ent);
8622 end Check_Abstract_Overriding;
8624 ------------------------------------------------
8625 -- Check_Access_Discriminant_Requires_Limited --
8626 ------------------------------------------------
8628 procedure Check_Access_Discriminant_Requires_Limited
8633 -- A discriminant_specification for an access discriminant shall appear
8634 -- only in the declaration for a task or protected type, or for a type
8635 -- with the reserved word 'limited' in its definition or in one of its
8636 -- ancestors. (RM 3.7(10))
8638 if Nkind (Discriminant_Type (D)) = N_Access_Definition
8639 and then not Is_Concurrent_Type (Current_Scope)
8640 and then not Is_Concurrent_Record_Type (Current_Scope)
8641 and then not Is_Limited_Record (Current_Scope)
8642 and then Ekind (Current_Scope) /= E_Limited_Private_Type
8645 ("access discriminants allowed only for limited types", Loc);
8647 end Check_Access_Discriminant_Requires_Limited;
8649 -----------------------------------
8650 -- Check_Aliased_Component_Types --
8651 -----------------------------------
8653 procedure Check_Aliased_Component_Types (T : Entity_Id) is
8657 -- ??? Also need to check components of record extensions, but not
8658 -- components of protected types (which are always limited).
8660 -- Ada 2005: AI-363 relaxes this rule, to allow heap objects of such
8661 -- types to be unconstrained. This is safe because it is illegal to
8662 -- create access subtypes to such types with explicit discriminant
8665 if not Is_Limited_Type (T) then
8666 if Ekind (T) = E_Record_Type then
8667 C := First_Component (T);
8668 while Present (C) loop
8670 and then Has_Discriminants (Etype (C))
8671 and then not Is_Constrained (Etype (C))
8672 and then not In_Instance_Body
8673 and then Ada_Version < Ada_05
8676 ("aliased component must be constrained (RM 3.6(11))",
8683 elsif Ekind (T) = E_Array_Type then
8684 if Has_Aliased_Components (T)
8685 and then Has_Discriminants (Component_Type (T))
8686 and then not Is_Constrained (Component_Type (T))
8687 and then not In_Instance_Body
8688 and then Ada_Version < Ada_05
8691 ("aliased component type must be constrained (RM 3.6(11))",
8696 end Check_Aliased_Component_Types;
8698 ----------------------
8699 -- Check_Completion --
8700 ----------------------
8702 procedure Check_Completion (Body_Id : Node_Id := Empty) is
8705 procedure Post_Error;
8706 -- Post error message for lack of completion for entity E
8712 procedure Post_Error is
8714 procedure Missing_Body;
8715 -- Output missing body message
8721 procedure Missing_Body is
8723 -- Spec is in same unit, so we can post on spec
8725 if In_Same_Source_Unit (Body_Id, E) then
8726 Error_Msg_N ("missing body for &", E);
8728 -- Spec is in a separate unit, so we have to post on the body
8731 Error_Msg_NE ("missing body for & declared#!", Body_Id, E);
8735 -- Start of processing for Post_Error
8738 if not Comes_From_Source (E) then
8740 if Ekind_In (E, E_Task_Type, E_Protected_Type) then
8741 -- It may be an anonymous protected type created for a
8742 -- single variable. Post error on variable, if present.
8748 Var := First_Entity (Current_Scope);
8749 while Present (Var) loop
8750 exit when Etype (Var) = E
8751 and then Comes_From_Source (Var);
8756 if Present (Var) then
8763 -- If a generated entity has no completion, then either previous
8764 -- semantic errors have disabled the expansion phase, or else we had
8765 -- missing subunits, or else we are compiling without expansion,
8766 -- or else something is very wrong.
8768 if not Comes_From_Source (E) then
8770 (Serious_Errors_Detected > 0
8771 or else Configurable_Run_Time_Violations > 0
8772 or else Subunits_Missing
8773 or else not Expander_Active);
8776 -- Here for source entity
8779 -- Here if no body to post the error message, so we post the error
8780 -- on the declaration that has no completion. This is not really
8781 -- the right place to post it, think about this later ???
8783 if No (Body_Id) then
8786 ("missing full declaration for }", Parent (E), E);
8789 ("missing body for &", Parent (E), E);
8792 -- Package body has no completion for a declaration that appears
8793 -- in the corresponding spec. Post error on the body, with a
8794 -- reference to the non-completed declaration.
8797 Error_Msg_Sloc := Sloc (E);
8801 ("missing full declaration for }!", Body_Id, E);
8803 elsif Is_Overloadable (E)
8804 and then Current_Entity_In_Scope (E) /= E
8806 -- It may be that the completion is mistyped and appears as
8807 -- a distinct overloading of the entity.
8810 Candidate : constant Entity_Id :=
8811 Current_Entity_In_Scope (E);
8812 Decl : constant Node_Id :=
8813 Unit_Declaration_Node (Candidate);
8816 if Is_Overloadable (Candidate)
8817 and then Ekind (Candidate) = Ekind (E)
8818 and then Nkind (Decl) = N_Subprogram_Body
8819 and then Acts_As_Spec (Decl)
8821 Check_Type_Conformant (Candidate, E);
8835 -- Start of processing for Check_Completion
8838 E := First_Entity (Current_Scope);
8839 while Present (E) loop
8840 if Is_Intrinsic_Subprogram (E) then
8843 -- The following situation requires special handling: a child unit
8844 -- that appears in the context clause of the body of its parent:
8846 -- procedure Parent.Child (...);
8848 -- with Parent.Child;
8849 -- package body Parent is
8851 -- Here Parent.Child appears as a local entity, but should not be
8852 -- flagged as requiring completion, because it is a compilation
8855 -- Ignore missing completion for a subprogram that does not come from
8856 -- source (including the _Call primitive operation of RAS types,
8857 -- which has to have the flag Comes_From_Source for other purposes):
8858 -- we assume that the expander will provide the missing completion.
8859 -- In case of previous errors, other expansion actions that provide
8860 -- bodies for null procedures with not be invoked, so inhibit message
8862 -- Note that E_Operator is not in the list that follows, because
8863 -- this kind is reserved for predefined operators, that are
8864 -- intrinsic and do not need completion.
8866 elsif Ekind (E) = E_Function
8867 or else Ekind (E) = E_Procedure
8868 or else Ekind (E) = E_Generic_Function
8869 or else Ekind (E) = E_Generic_Procedure
8871 if Has_Completion (E) then
8874 elsif Is_Subprogram (E) and then Is_Abstract_Subprogram (E) then
8877 elsif Is_Subprogram (E)
8878 and then (not Comes_From_Source (E)
8879 or else Chars (E) = Name_uCall)
8884 Nkind (Parent (Unit_Declaration_Node (E))) = N_Compilation_Unit
8888 elsif Nkind (Parent (E)) = N_Procedure_Specification
8889 and then Null_Present (Parent (E))
8890 and then Serious_Errors_Detected > 0
8898 elsif Is_Entry (E) then
8899 if not Has_Completion (E) and then
8900 (Ekind (Scope (E)) = E_Protected_Object
8901 or else Ekind (Scope (E)) = E_Protected_Type)
8906 elsif Is_Package_Or_Generic_Package (E) then
8907 if Unit_Requires_Body (E) then
8908 if not Has_Completion (E)
8909 and then Nkind (Parent (Unit_Declaration_Node (E))) /=
8915 elsif not Is_Child_Unit (E) then
8916 May_Need_Implicit_Body (E);
8919 elsif Ekind (E) = E_Incomplete_Type
8920 and then No (Underlying_Type (E))
8924 elsif (Ekind (E) = E_Task_Type or else
8925 Ekind (E) = E_Protected_Type)
8926 and then not Has_Completion (E)
8930 -- A single task declared in the current scope is a constant, verify
8931 -- that the body of its anonymous type is in the same scope. If the
8932 -- task is defined elsewhere, this may be a renaming declaration for
8933 -- which no completion is needed.
8935 elsif Ekind (E) = E_Constant
8936 and then Ekind (Etype (E)) = E_Task_Type
8937 and then not Has_Completion (Etype (E))
8938 and then Scope (Etype (E)) = Current_Scope
8942 elsif Ekind (E) = E_Protected_Object
8943 and then not Has_Completion (Etype (E))
8947 elsif Ekind (E) = E_Record_Type then
8948 if Is_Tagged_Type (E) then
8949 Check_Abstract_Overriding (E);
8950 Check_Conventions (E);
8953 Check_Aliased_Component_Types (E);
8955 elsif Ekind (E) = E_Array_Type then
8956 Check_Aliased_Component_Types (E);
8962 end Check_Completion;
8964 ----------------------------
8965 -- Check_Delta_Expression --
8966 ----------------------------
8968 procedure Check_Delta_Expression (E : Node_Id) is
8970 if not (Is_Real_Type (Etype (E))) then
8971 Wrong_Type (E, Any_Real);
8973 elsif not Is_OK_Static_Expression (E) then
8974 Flag_Non_Static_Expr
8975 ("non-static expression used for delta value!", E);
8977 elsif not UR_Is_Positive (Expr_Value_R (E)) then
8978 Error_Msg_N ("delta expression must be positive", E);
8984 -- If any of above errors occurred, then replace the incorrect
8985 -- expression by the real 0.1, which should prevent further errors.
8988 Make_Real_Literal (Sloc (E), Ureal_Tenth));
8989 Analyze_And_Resolve (E, Standard_Float);
8990 end Check_Delta_Expression;
8992 -----------------------------
8993 -- Check_Digits_Expression --
8994 -----------------------------
8996 procedure Check_Digits_Expression (E : Node_Id) is
8998 if not (Is_Integer_Type (Etype (E))) then
8999 Wrong_Type (E, Any_Integer);
9001 elsif not Is_OK_Static_Expression (E) then
9002 Flag_Non_Static_Expr
9003 ("non-static expression used for digits value!", E);
9005 elsif Expr_Value (E) <= 0 then
9006 Error_Msg_N ("digits value must be greater than zero", E);
9012 -- If any of above errors occurred, then replace the incorrect
9013 -- expression by the integer 1, which should prevent further errors.
9015 Rewrite (E, Make_Integer_Literal (Sloc (E), 1));
9016 Analyze_And_Resolve (E, Standard_Integer);
9018 end Check_Digits_Expression;
9020 --------------------------
9021 -- Check_Initialization --
9022 --------------------------
9024 procedure Check_Initialization (T : Entity_Id; Exp : Node_Id) is
9026 if Is_Limited_Type (T)
9027 and then not In_Instance
9028 and then not In_Inlined_Body
9030 if not OK_For_Limited_Init (T, Exp) then
9032 -- In GNAT mode, this is just a warning, to allow it to be evilly
9033 -- turned off. Otherwise it is a real error.
9037 ("?cannot initialize entities of limited type!", Exp);
9039 elsif Ada_Version < Ada_05 then
9041 ("cannot initialize entities of limited type", Exp);
9042 Explain_Limited_Type (T, Exp);
9045 -- Specialize error message according to kind of illegal
9046 -- initial expression.
9048 if Nkind (Exp) = N_Type_Conversion
9049 and then Nkind (Expression (Exp)) = N_Function_Call
9052 ("illegal context for call"
9053 & " to function with limited result", Exp);
9057 ("initialization of limited object requires aggregate "
9058 & "or function call", Exp);
9063 end Check_Initialization;
9065 ----------------------
9066 -- Check_Interfaces --
9067 ----------------------
9069 procedure Check_Interfaces (N : Node_Id; Def : Node_Id) is
9070 Parent_Type : constant Entity_Id := Etype (Defining_Identifier (N));
9073 Iface_Def : Node_Id;
9074 Iface_Typ : Entity_Id;
9075 Parent_Node : Node_Id;
9077 Is_Task : Boolean := False;
9078 -- Set True if parent type or any progenitor is a task interface
9080 Is_Protected : Boolean := False;
9081 -- Set True if parent type or any progenitor is a protected interface
9083 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id);
9084 -- Check that a progenitor is compatible with declaration.
9085 -- Error is posted on Error_Node.
9091 procedure Check_Ifaces (Iface_Def : Node_Id; Error_Node : Node_Id) is
9092 Iface_Id : constant Entity_Id :=
9093 Defining_Identifier (Parent (Iface_Def));
9097 if Nkind (N) = N_Private_Extension_Declaration then
9100 Type_Def := Type_Definition (N);
9103 if Is_Task_Interface (Iface_Id) then
9106 elsif Is_Protected_Interface (Iface_Id) then
9107 Is_Protected := True;
9110 if Is_Synchronized_Interface (Iface_Id) then
9112 -- A consequence of 3.9.4 (6/2) and 7.3 (7.2/2) is that a private
9113 -- extension derived from a synchronized interface must explicitly
9114 -- be declared synchronized, because the full view will be a
9115 -- synchronized type.
9117 if Nkind (N) = N_Private_Extension_Declaration then
9118 if not Synchronized_Present (N) then
9120 ("private extension of& must be explicitly synchronized",
9124 -- However, by 3.9.4(16/2), a full type that is a record extension
9125 -- is never allowed to derive from a synchronized interface (note
9126 -- that interfaces must be excluded from this check, because those
9127 -- are represented by derived type definitions in some cases).
9129 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9130 and then not Interface_Present (Type_Definition (N))
9132 Error_Msg_N ("record extension cannot derive from synchronized"
9133 & " interface", Error_Node);
9137 -- Check that the characteristics of the progenitor are compatible
9138 -- with the explicit qualifier in the declaration.
9139 -- The check only applies to qualifiers that come from source.
9140 -- Limited_Present also appears in the declaration of corresponding
9141 -- records, and the check does not apply to them.
9143 if Limited_Present (Type_Def)
9145 Is_Concurrent_Record_Type (Defining_Identifier (N))
9147 if Is_Limited_Interface (Parent_Type)
9148 and then not Is_Limited_Interface (Iface_Id)
9151 ("progenitor& must be limited interface",
9152 Error_Node, Iface_Id);
9155 (Task_Present (Iface_Def)
9156 or else Protected_Present (Iface_Def)
9157 or else Synchronized_Present (Iface_Def))
9158 and then Nkind (N) /= N_Private_Extension_Declaration
9159 and then not Error_Posted (N)
9162 ("progenitor& must be limited interface",
9163 Error_Node, Iface_Id);
9166 -- Protected interfaces can only inherit from limited, synchronized
9167 -- or protected interfaces.
9169 elsif Nkind (N) = N_Full_Type_Declaration
9170 and then Protected_Present (Type_Def)
9172 if Limited_Present (Iface_Def)
9173 or else Synchronized_Present (Iface_Def)
9174 or else Protected_Present (Iface_Def)
9178 elsif Task_Present (Iface_Def) then
9179 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9180 & " from task interface", Error_Node);
9183 Error_Msg_N ("(Ada 2005) protected interface cannot inherit"
9184 & " from non-limited interface", Error_Node);
9187 -- Ada 2005 (AI-345): Synchronized interfaces can only inherit from
9188 -- limited and synchronized.
9190 elsif Synchronized_Present (Type_Def) then
9191 if Limited_Present (Iface_Def)
9192 or else Synchronized_Present (Iface_Def)
9196 elsif Protected_Present (Iface_Def)
9197 and then Nkind (N) /= N_Private_Extension_Declaration
9199 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9200 & " from protected interface", Error_Node);
9202 elsif Task_Present (Iface_Def)
9203 and then Nkind (N) /= N_Private_Extension_Declaration
9205 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9206 & " from task interface", Error_Node);
9208 elsif not Is_Limited_Interface (Iface_Id) then
9209 Error_Msg_N ("(Ada 2005) synchronized interface cannot inherit"
9210 & " from non-limited interface", Error_Node);
9213 -- Ada 2005 (AI-345): Task interfaces can only inherit from limited,
9214 -- synchronized or task interfaces.
9216 elsif Nkind (N) = N_Full_Type_Declaration
9217 and then Task_Present (Type_Def)
9219 if Limited_Present (Iface_Def)
9220 or else Synchronized_Present (Iface_Def)
9221 or else Task_Present (Iface_Def)
9225 elsif Protected_Present (Iface_Def) then
9226 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9227 & " protected interface", Error_Node);
9230 Error_Msg_N ("(Ada 2005) task interface cannot inherit from"
9231 & " non-limited interface", Error_Node);
9236 -- Start of processing for Check_Interfaces
9239 if Is_Interface (Parent_Type) then
9240 if Is_Task_Interface (Parent_Type) then
9243 elsif Is_Protected_Interface (Parent_Type) then
9244 Is_Protected := True;
9248 if Nkind (N) = N_Private_Extension_Declaration then
9250 -- Check that progenitors are compatible with declaration
9252 Iface := First (Interface_List (Def));
9253 while Present (Iface) loop
9254 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9256 Parent_Node := Parent (Base_Type (Iface_Typ));
9257 Iface_Def := Type_Definition (Parent_Node);
9259 if not Is_Interface (Iface_Typ) then
9260 Diagnose_Interface (Iface, Iface_Typ);
9263 Check_Ifaces (Iface_Def, Iface);
9269 if Is_Task and Is_Protected then
9271 ("type cannot derive from task and protected interface", N);
9277 -- Full type declaration of derived type.
9278 -- Check compatibility with parent if it is interface type
9280 if Nkind (Type_Definition (N)) = N_Derived_Type_Definition
9281 and then Is_Interface (Parent_Type)
9283 Parent_Node := Parent (Parent_Type);
9285 -- More detailed checks for interface varieties
9288 (Iface_Def => Type_Definition (Parent_Node),
9289 Error_Node => Subtype_Indication (Type_Definition (N)));
9292 Iface := First (Interface_List (Def));
9293 while Present (Iface) loop
9294 Iface_Typ := Find_Type_Of_Subtype_Indic (Iface);
9296 Parent_Node := Parent (Base_Type (Iface_Typ));
9297 Iface_Def := Type_Definition (Parent_Node);
9299 if not Is_Interface (Iface_Typ) then
9300 Diagnose_Interface (Iface, Iface_Typ);
9303 -- "The declaration of a specific descendant of an interface
9304 -- type freezes the interface type" RM 13.14
9306 Freeze_Before (N, Iface_Typ);
9307 Check_Ifaces (Iface_Def, Error_Node => Iface);
9313 if Is_Task and Is_Protected then
9315 ("type cannot derive from task and protected interface", N);
9317 end Check_Interfaces;
9319 ------------------------------------
9320 -- Check_Or_Process_Discriminants --
9321 ------------------------------------
9323 -- If an incomplete or private type declaration was already given for the
9324 -- type, the discriminants may have already been processed if they were
9325 -- present on the incomplete declaration. In this case a full conformance
9326 -- check is performed otherwise just process them.
9328 procedure Check_Or_Process_Discriminants
9331 Prev : Entity_Id := Empty)
9334 if Has_Discriminants (T) then
9336 -- Make the discriminants visible to component declarations
9343 D := First_Discriminant (T);
9344 while Present (D) loop
9345 Prev := Current_Entity (D);
9346 Set_Current_Entity (D);
9347 Set_Is_Immediately_Visible (D);
9348 Set_Homonym (D, Prev);
9350 -- Ada 2005 (AI-230): Access discriminant allowed in
9351 -- non-limited record types.
9353 if Ada_Version < Ada_05 then
9355 -- This restriction gets applied to the full type here. It
9356 -- has already been applied earlier to the partial view.
9358 Check_Access_Discriminant_Requires_Limited (Parent (D), N);
9361 Next_Discriminant (D);
9365 elsif Present (Discriminant_Specifications (N)) then
9366 Process_Discriminants (N, Prev);
9368 end Check_Or_Process_Discriminants;
9370 ----------------------
9371 -- Check_Real_Bound --
9372 ----------------------
9374 procedure Check_Real_Bound (Bound : Node_Id) is
9376 if not Is_Real_Type (Etype (Bound)) then
9378 ("bound in real type definition must be of real type", Bound);
9380 elsif not Is_OK_Static_Expression (Bound) then
9381 Flag_Non_Static_Expr
9382 ("non-static expression used for real type bound!", Bound);
9389 (Bound, Make_Real_Literal (Sloc (Bound), Ureal_0));
9391 Resolve (Bound, Standard_Float);
9392 end Check_Real_Bound;
9394 ------------------------------
9395 -- Complete_Private_Subtype --
9396 ------------------------------
9398 procedure Complete_Private_Subtype
9401 Full_Base : Entity_Id;
9402 Related_Nod : Node_Id)
9404 Save_Next_Entity : Entity_Id;
9405 Save_Homonym : Entity_Id;
9408 -- Set semantic attributes for (implicit) private subtype completion.
9409 -- If the full type has no discriminants, then it is a copy of the full
9410 -- view of the base. Otherwise, it is a subtype of the base with a
9411 -- possible discriminant constraint. Save and restore the original
9412 -- Next_Entity field of full to ensure that the calls to Copy_Node
9413 -- do not corrupt the entity chain.
9415 -- Note that the type of the full view is the same entity as the type of
9416 -- the partial view. In this fashion, the subtype has access to the
9417 -- correct view of the parent.
9419 Save_Next_Entity := Next_Entity (Full);
9420 Save_Homonym := Homonym (Priv);
9422 case Ekind (Full_Base) is
9423 when E_Record_Type |
9429 Copy_Node (Priv, Full);
9431 Set_Has_Discriminants (Full, Has_Discriminants (Full_Base));
9432 Set_First_Entity (Full, First_Entity (Full_Base));
9433 Set_Last_Entity (Full, Last_Entity (Full_Base));
9436 Copy_Node (Full_Base, Full);
9437 Set_Chars (Full, Chars (Priv));
9438 Conditional_Delay (Full, Priv);
9439 Set_Sloc (Full, Sloc (Priv));
9442 Set_Next_Entity (Full, Save_Next_Entity);
9443 Set_Homonym (Full, Save_Homonym);
9444 Set_Associated_Node_For_Itype (Full, Related_Nod);
9446 -- Set common attributes for all subtypes
9448 Set_Ekind (Full, Subtype_Kind (Ekind (Full_Base)));
9450 -- The Etype of the full view is inconsistent. Gigi needs to see the
9451 -- structural full view, which is what the current scheme gives:
9452 -- the Etype of the full view is the etype of the full base. However,
9453 -- if the full base is a derived type, the full view then looks like
9454 -- a subtype of the parent, not a subtype of the full base. If instead
9457 -- Set_Etype (Full, Full_Base);
9459 -- then we get inconsistencies in the front-end (confusion between
9460 -- views). Several outstanding bugs are related to this ???
9462 Set_Is_First_Subtype (Full, False);
9463 Set_Scope (Full, Scope (Priv));
9464 Set_Size_Info (Full, Full_Base);
9465 Set_RM_Size (Full, RM_Size (Full_Base));
9466 Set_Is_Itype (Full);
9468 -- A subtype of a private-type-without-discriminants, whose full-view
9469 -- has discriminants with default expressions, is not constrained!
9471 if not Has_Discriminants (Priv) then
9472 Set_Is_Constrained (Full, Is_Constrained (Full_Base));
9474 if Has_Discriminants (Full_Base) then
9475 Set_Discriminant_Constraint
9476 (Full, Discriminant_Constraint (Full_Base));
9478 -- The partial view may have been indefinite, the full view
9481 Set_Has_Unknown_Discriminants
9482 (Full, Has_Unknown_Discriminants (Full_Base));
9486 Set_First_Rep_Item (Full, First_Rep_Item (Full_Base));
9487 Set_Depends_On_Private (Full, Has_Private_Component (Full));
9489 -- Freeze the private subtype entity if its parent is delayed, and not
9490 -- already frozen. We skip this processing if the type is an anonymous
9491 -- subtype of a record component, or is the corresponding record of a
9492 -- protected type, since ???
9494 if not Is_Type (Scope (Full)) then
9495 Set_Has_Delayed_Freeze (Full,
9496 Has_Delayed_Freeze (Full_Base)
9497 and then (not Is_Frozen (Full_Base)));
9500 Set_Freeze_Node (Full, Empty);
9501 Set_Is_Frozen (Full, False);
9502 Set_Full_View (Priv, Full);
9504 if Has_Discriminants (Full) then
9505 Set_Stored_Constraint_From_Discriminant_Constraint (Full);
9506 Set_Stored_Constraint (Priv, Stored_Constraint (Full));
9508 if Has_Unknown_Discriminants (Full) then
9509 Set_Discriminant_Constraint (Full, No_Elist);
9513 if Ekind (Full_Base) = E_Record_Type
9514 and then Has_Discriminants (Full_Base)
9515 and then Has_Discriminants (Priv) -- might not, if errors
9516 and then not Has_Unknown_Discriminants (Priv)
9517 and then not Is_Empty_Elmt_List (Discriminant_Constraint (Priv))
9519 Create_Constrained_Components
9520 (Full, Related_Nod, Full_Base, Discriminant_Constraint (Priv));
9522 -- If the full base is itself derived from private, build a congruent
9523 -- subtype of its underlying type, for use by the back end. For a
9524 -- constrained record component, the declaration cannot be placed on
9525 -- the component list, but it must nevertheless be built an analyzed, to
9526 -- supply enough information for Gigi to compute the size of component.
9528 elsif Ekind (Full_Base) in Private_Kind
9529 and then Is_Derived_Type (Full_Base)
9530 and then Has_Discriminants (Full_Base)
9531 and then (Ekind (Current_Scope) /= E_Record_Subtype)
9533 if not Is_Itype (Priv)
9535 Nkind (Subtype_Indication (Parent (Priv))) = N_Subtype_Indication
9537 Build_Underlying_Full_View
9538 (Parent (Priv), Full, Etype (Full_Base));
9540 elsif Nkind (Related_Nod) = N_Component_Declaration then
9541 Build_Underlying_Full_View (Related_Nod, Full, Etype (Full_Base));
9544 elsif Is_Record_Type (Full_Base) then
9546 -- Show Full is simply a renaming of Full_Base
9548 Set_Cloned_Subtype (Full, Full_Base);
9551 -- It is unsafe to share to bounds of a scalar type, because the Itype
9552 -- is elaborated on demand, and if a bound is non-static then different
9553 -- orders of elaboration in different units will lead to different
9554 -- external symbols.
9556 if Is_Scalar_Type (Full_Base) then
9557 Set_Scalar_Range (Full,
9558 Make_Range (Sloc (Related_Nod),
9560 Duplicate_Subexpr_No_Checks (Type_Low_Bound (Full_Base)),
9562 Duplicate_Subexpr_No_Checks (Type_High_Bound (Full_Base))));
9564 -- This completion inherits the bounds of the full parent, but if
9565 -- the parent is an unconstrained floating point type, so is the
9568 if Is_Floating_Point_Type (Full_Base) then
9569 Set_Includes_Infinities
9570 (Scalar_Range (Full), Has_Infinities (Full_Base));
9574 -- ??? It seems that a lot of fields are missing that should be copied
9575 -- from Full_Base to Full. Here are some that are introduced in a
9576 -- non-disruptive way but a cleanup is necessary.
9578 if Is_Tagged_Type (Full_Base) then
9579 Set_Is_Tagged_Type (Full);
9580 Set_Primitive_Operations (Full, Primitive_Operations (Full_Base));
9582 -- Inherit class_wide type of full_base in case the partial view was
9583 -- not tagged. Otherwise it has already been created when the private
9584 -- subtype was analyzed.
9586 if No (Class_Wide_Type (Full)) then
9587 Set_Class_Wide_Type (Full, Class_Wide_Type (Full_Base));
9590 -- If this is a subtype of a protected or task type, constrain its
9591 -- corresponding record, unless this is a subtype without constraints,
9592 -- i.e. a simple renaming as with an actual subtype in an instance.
9594 elsif Is_Concurrent_Type (Full_Base) then
9595 if Has_Discriminants (Full)
9596 and then Present (Corresponding_Record_Type (Full_Base))
9598 not Is_Empty_Elmt_List (Discriminant_Constraint (Full))
9600 Set_Corresponding_Record_Type (Full,
9601 Constrain_Corresponding_Record
9602 (Full, Corresponding_Record_Type (Full_Base),
9603 Related_Nod, Full_Base));
9606 Set_Corresponding_Record_Type (Full,
9607 Corresponding_Record_Type (Full_Base));
9610 end Complete_Private_Subtype;
9612 ----------------------------
9613 -- Constant_Redeclaration --
9614 ----------------------------
9616 procedure Constant_Redeclaration
9621 Prev : constant Entity_Id := Current_Entity_In_Scope (Id);
9622 Obj_Def : constant Node_Id := Object_Definition (N);
9625 procedure Check_Possible_Deferred_Completion
9626 (Prev_Id : Entity_Id;
9627 Prev_Obj_Def : Node_Id;
9628 Curr_Obj_Def : Node_Id);
9629 -- Determine whether the two object definitions describe the partial
9630 -- and the full view of a constrained deferred constant. Generate
9631 -- a subtype for the full view and verify that it statically matches
9632 -- the subtype of the partial view.
9634 procedure Check_Recursive_Declaration (Typ : Entity_Id);
9635 -- If deferred constant is an access type initialized with an allocator,
9636 -- check whether there is an illegal recursion in the definition,
9637 -- through a default value of some record subcomponent. This is normally
9638 -- detected when generating init procs, but requires this additional
9639 -- mechanism when expansion is disabled.
9641 ----------------------------------------
9642 -- Check_Possible_Deferred_Completion --
9643 ----------------------------------------
9645 procedure Check_Possible_Deferred_Completion
9646 (Prev_Id : Entity_Id;
9647 Prev_Obj_Def : Node_Id;
9648 Curr_Obj_Def : Node_Id)
9651 if Nkind (Prev_Obj_Def) = N_Subtype_Indication
9652 and then Present (Constraint (Prev_Obj_Def))
9653 and then Nkind (Curr_Obj_Def) = N_Subtype_Indication
9654 and then Present (Constraint (Curr_Obj_Def))
9657 Loc : constant Source_Ptr := Sloc (N);
9658 Def_Id : constant Entity_Id :=
9659 Make_Defining_Identifier (Loc,
9660 New_Internal_Name ('S'));
9661 Decl : constant Node_Id :=
9662 Make_Subtype_Declaration (Loc,
9663 Defining_Identifier =>
9665 Subtype_Indication =>
9666 Relocate_Node (Curr_Obj_Def));
9669 Insert_Before_And_Analyze (N, Decl);
9670 Set_Etype (Id, Def_Id);
9672 if not Subtypes_Statically_Match (Etype (Prev_Id), Def_Id) then
9673 Error_Msg_Sloc := Sloc (Prev_Id);
9674 Error_Msg_N ("subtype does not statically match deferred " &
9679 end Check_Possible_Deferred_Completion;
9681 ---------------------------------
9682 -- Check_Recursive_Declaration --
9683 ---------------------------------
9685 procedure Check_Recursive_Declaration (Typ : Entity_Id) is
9689 if Is_Record_Type (Typ) then
9690 Comp := First_Component (Typ);
9691 while Present (Comp) loop
9692 if Comes_From_Source (Comp) then
9693 if Present (Expression (Parent (Comp)))
9694 and then Is_Entity_Name (Expression (Parent (Comp)))
9695 and then Entity (Expression (Parent (Comp))) = Prev
9697 Error_Msg_Sloc := Sloc (Parent (Comp));
9699 ("illegal circularity with declaration for&#",
9703 elsif Is_Record_Type (Etype (Comp)) then
9704 Check_Recursive_Declaration (Etype (Comp));
9708 Next_Component (Comp);
9711 end Check_Recursive_Declaration;
9713 -- Start of processing for Constant_Redeclaration
9716 if Nkind (Parent (Prev)) = N_Object_Declaration then
9717 if Nkind (Object_Definition
9718 (Parent (Prev))) = N_Subtype_Indication
9720 -- Find type of new declaration. The constraints of the two
9721 -- views must match statically, but there is no point in
9722 -- creating an itype for the full view.
9724 if Nkind (Obj_Def) = N_Subtype_Indication then
9725 Find_Type (Subtype_Mark (Obj_Def));
9726 New_T := Entity (Subtype_Mark (Obj_Def));
9729 Find_Type (Obj_Def);
9730 New_T := Entity (Obj_Def);
9736 -- The full view may impose a constraint, even if the partial
9737 -- view does not, so construct the subtype.
9739 New_T := Find_Type_Of_Object (Obj_Def, N);
9744 -- Current declaration is illegal, diagnosed below in Enter_Name
9750 -- If previous full declaration or a renaming declaration exists, or if
9751 -- a homograph is present, let Enter_Name handle it, either with an
9752 -- error or with the removal of an overridden implicit subprogram.
9754 if Ekind (Prev) /= E_Constant
9755 or else Nkind (Parent (Prev)) = N_Object_Renaming_Declaration
9756 or else Present (Expression (Parent (Prev)))
9757 or else Present (Full_View (Prev))
9761 -- Verify that types of both declarations match, or else that both types
9762 -- are anonymous access types whose designated subtypes statically match
9763 -- (as allowed in Ada 2005 by AI-385).
9765 elsif Base_Type (Etype (Prev)) /= Base_Type (New_T)
9767 (Ekind (Etype (Prev)) /= E_Anonymous_Access_Type
9768 or else Ekind (Etype (New_T)) /= E_Anonymous_Access_Type
9769 or else Is_Access_Constant (Etype (New_T)) /=
9770 Is_Access_Constant (Etype (Prev))
9771 or else Can_Never_Be_Null (Etype (New_T)) /=
9772 Can_Never_Be_Null (Etype (Prev))
9773 or else Null_Exclusion_Present (Parent (Prev)) /=
9774 Null_Exclusion_Present (Parent (Id))
9775 or else not Subtypes_Statically_Match
9776 (Designated_Type (Etype (Prev)),
9777 Designated_Type (Etype (New_T))))
9779 Error_Msg_Sloc := Sloc (Prev);
9780 Error_Msg_N ("type does not match declaration#", N);
9781 Set_Full_View (Prev, Id);
9782 Set_Etype (Id, Any_Type);
9785 Null_Exclusion_Present (Parent (Prev))
9786 and then not Null_Exclusion_Present (N)
9788 Error_Msg_Sloc := Sloc (Prev);
9789 Error_Msg_N ("null-exclusion does not match declaration#", N);
9790 Set_Full_View (Prev, Id);
9791 Set_Etype (Id, Any_Type);
9793 -- If so, process the full constant declaration
9796 -- RM 7.4 (6): If the subtype defined by the subtype_indication in
9797 -- the deferred declaration is constrained, then the subtype defined
9798 -- by the subtype_indication in the full declaration shall match it
9801 Check_Possible_Deferred_Completion
9803 Prev_Obj_Def => Object_Definition (Parent (Prev)),
9804 Curr_Obj_Def => Obj_Def);
9806 Set_Full_View (Prev, Id);
9807 Set_Is_Public (Id, Is_Public (Prev));
9808 Set_Is_Internal (Id);
9809 Append_Entity (Id, Current_Scope);
9811 -- Check ALIASED present if present before (RM 7.4(7))
9813 if Is_Aliased (Prev)
9814 and then not Aliased_Present (N)
9816 Error_Msg_Sloc := Sloc (Prev);
9817 Error_Msg_N ("ALIASED required (see declaration#)", N);
9820 -- Check that placement is in private part and that the incomplete
9821 -- declaration appeared in the visible part.
9823 if Ekind (Current_Scope) = E_Package
9824 and then not In_Private_Part (Current_Scope)
9826 Error_Msg_Sloc := Sloc (Prev);
9827 Error_Msg_N ("full constant for declaration#"
9828 & " must be in private part", N);
9830 elsif Ekind (Current_Scope) = E_Package
9832 List_Containing (Parent (Prev)) /=
9833 Visible_Declarations
9834 (Specification (Unit_Declaration_Node (Current_Scope)))
9837 ("deferred constant must be declared in visible part",
9841 if Is_Access_Type (T)
9842 and then Nkind (Expression (N)) = N_Allocator
9844 Check_Recursive_Declaration (Designated_Type (T));
9847 end Constant_Redeclaration;
9849 ----------------------
9850 -- Constrain_Access --
9851 ----------------------
9853 procedure Constrain_Access
9854 (Def_Id : in out Entity_Id;
9856 Related_Nod : Node_Id)
9858 T : constant Entity_Id := Entity (Subtype_Mark (S));
9859 Desig_Type : constant Entity_Id := Designated_Type (T);
9860 Desig_Subtype : Entity_Id := Create_Itype (E_Void, Related_Nod);
9861 Constraint_OK : Boolean := True;
9863 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean;
9864 -- Simple predicate to test for defaulted discriminants
9865 -- Shouldn't this be in sem_util???
9867 ---------------------------------
9868 -- Has_Defaulted_Discriminants --
9869 ---------------------------------
9871 function Has_Defaulted_Discriminants (Typ : Entity_Id) return Boolean is
9873 return Has_Discriminants (Typ)
9874 and then Present (First_Discriminant (Typ))
9876 (Discriminant_Default_Value (First_Discriminant (Typ)));
9877 end Has_Defaulted_Discriminants;
9879 -- Start of processing for Constrain_Access
9882 if Is_Array_Type (Desig_Type) then
9883 Constrain_Array (Desig_Subtype, S, Related_Nod, Def_Id, 'P');
9885 elsif (Is_Record_Type (Desig_Type)
9886 or else Is_Incomplete_Or_Private_Type (Desig_Type))
9887 and then not Is_Constrained (Desig_Type)
9889 -- ??? The following code is a temporary kludge to ignore a
9890 -- discriminant constraint on access type if it is constraining
9891 -- the current record. Avoid creating the implicit subtype of the
9892 -- record we are currently compiling since right now, we cannot
9893 -- handle these. For now, just return the access type itself.
9895 if Desig_Type = Current_Scope
9896 and then No (Def_Id)
9898 Set_Ekind (Desig_Subtype, E_Record_Subtype);
9899 Def_Id := Entity (Subtype_Mark (S));
9901 -- This call added to ensure that the constraint is analyzed
9902 -- (needed for a B test). Note that we still return early from
9903 -- this procedure to avoid recursive processing. ???
9905 Constrain_Discriminated_Type
9906 (Desig_Subtype, S, Related_Nod, For_Access => True);
9910 if (Ekind (T) = E_General_Access_Type
9911 or else Ada_Version >= Ada_05)
9912 and then Has_Private_Declaration (Desig_Type)
9913 and then In_Open_Scopes (Scope (Desig_Type))
9914 and then Has_Discriminants (Desig_Type)
9916 -- Enforce rule that the constraint is illegal if there is
9917 -- an unconstrained view of the designated type. This means
9918 -- that the partial view (either a private type declaration or
9919 -- a derivation from a private type) has no discriminants.
9920 -- (Defect Report 8652/0008, Technical Corrigendum 1, checked
9921 -- by ACATS B371001).
9923 -- Rule updated for Ada 2005: the private type is said to have
9924 -- a constrained partial view, given that objects of the type
9925 -- can be declared. Furthermore, the rule applies to all access
9926 -- types, unlike the rule concerning default discriminants.
9929 Pack : constant Node_Id :=
9930 Unit_Declaration_Node (Scope (Desig_Type));
9935 if Nkind (Pack) = N_Package_Declaration then
9936 Decls := Visible_Declarations (Specification (Pack));
9937 Decl := First (Decls);
9938 while Present (Decl) loop
9939 if (Nkind (Decl) = N_Private_Type_Declaration
9941 Chars (Defining_Identifier (Decl)) =
9945 (Nkind (Decl) = N_Full_Type_Declaration
9947 Chars (Defining_Identifier (Decl)) =
9949 and then Is_Derived_Type (Desig_Type)
9951 Has_Private_Declaration (Etype (Desig_Type)))
9953 if No (Discriminant_Specifications (Decl)) then
9955 ("cannot constrain general access type if " &
9956 "designated type has constrained partial view",
9969 Constrain_Discriminated_Type (Desig_Subtype, S, Related_Nod,
9970 For_Access => True);
9972 elsif (Is_Task_Type (Desig_Type)
9973 or else Is_Protected_Type (Desig_Type))
9974 and then not Is_Constrained (Desig_Type)
9976 Constrain_Concurrent
9977 (Desig_Subtype, S, Related_Nod, Desig_Type, ' ');
9980 Error_Msg_N ("invalid constraint on access type", S);
9981 Desig_Subtype := Desig_Type; -- Ignore invalid constraint.
9982 Constraint_OK := False;
9986 Def_Id := Create_Itype (E_Access_Subtype, Related_Nod);
9988 Set_Ekind (Def_Id, E_Access_Subtype);
9991 if Constraint_OK then
9992 Set_Etype (Def_Id, Base_Type (T));
9994 if Is_Private_Type (Desig_Type) then
9995 Prepare_Private_Subtype_Completion (Desig_Subtype, Related_Nod);
9998 Set_Etype (Def_Id, Any_Type);
10001 Set_Size_Info (Def_Id, T);
10002 Set_Is_Constrained (Def_Id, Constraint_OK);
10003 Set_Directly_Designated_Type (Def_Id, Desig_Subtype);
10004 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10005 Set_Is_Access_Constant (Def_Id, Is_Access_Constant (T));
10007 Conditional_Delay (Def_Id, T);
10009 -- AI-363 : Subtypes of general access types whose designated types have
10010 -- default discriminants are disallowed. In instances, the rule has to
10011 -- be checked against the actual, of which T is the subtype. In a
10012 -- generic body, the rule is checked assuming that the actual type has
10013 -- defaulted discriminants.
10015 if Ada_Version >= Ada_05 or else Warn_On_Ada_2005_Compatibility then
10016 if Ekind (Base_Type (T)) = E_General_Access_Type
10017 and then Has_Defaulted_Discriminants (Desig_Type)
10019 if Ada_Version < Ada_05 then
10021 ("access subtype of general access type would not " &
10022 "be allowed in Ada 2005?", S);
10025 ("access subype of general access type not allowed", S);
10028 Error_Msg_N ("\discriminants have defaults", S);
10030 elsif Is_Access_Type (T)
10031 and then Is_Generic_Type (Desig_Type)
10032 and then Has_Discriminants (Desig_Type)
10033 and then In_Package_Body (Current_Scope)
10035 if Ada_Version < Ada_05 then
10037 ("access subtype would not be allowed in generic body " &
10038 "in Ada 2005?", S);
10041 ("access subtype not allowed in generic body", S);
10045 ("\designated type is a discriminated formal", S);
10048 end Constrain_Access;
10050 ---------------------
10051 -- Constrain_Array --
10052 ---------------------
10054 procedure Constrain_Array
10055 (Def_Id : in out Entity_Id;
10057 Related_Nod : Node_Id;
10058 Related_Id : Entity_Id;
10059 Suffix : Character)
10061 C : constant Node_Id := Constraint (SI);
10062 Number_Of_Constraints : Nat := 0;
10065 Constraint_OK : Boolean := True;
10068 T := Entity (Subtype_Mark (SI));
10070 if Ekind (T) in Access_Kind then
10071 T := Designated_Type (T);
10074 -- If an index constraint follows a subtype mark in a subtype indication
10075 -- then the type or subtype denoted by the subtype mark must not already
10076 -- impose an index constraint. The subtype mark must denote either an
10077 -- unconstrained array type or an access type whose designated type
10078 -- is such an array type... (RM 3.6.1)
10080 if Is_Constrained (T) then
10082 ("array type is already constrained", Subtype_Mark (SI));
10083 Constraint_OK := False;
10086 S := First (Constraints (C));
10087 while Present (S) loop
10088 Number_Of_Constraints := Number_Of_Constraints + 1;
10092 -- In either case, the index constraint must provide a discrete
10093 -- range for each index of the array type and the type of each
10094 -- discrete range must be the same as that of the corresponding
10095 -- index. (RM 3.6.1)
10097 if Number_Of_Constraints /= Number_Dimensions (T) then
10098 Error_Msg_NE ("incorrect number of index constraints for }", C, T);
10099 Constraint_OK := False;
10102 S := First (Constraints (C));
10103 Index := First_Index (T);
10106 -- Apply constraints to each index type
10108 for J in 1 .. Number_Of_Constraints loop
10109 Constrain_Index (Index, S, Related_Nod, Related_Id, Suffix, J);
10117 if No (Def_Id) then
10119 Create_Itype (E_Array_Subtype, Related_Nod, Related_Id, Suffix);
10120 Set_Parent (Def_Id, Related_Nod);
10123 Set_Ekind (Def_Id, E_Array_Subtype);
10126 Set_Size_Info (Def_Id, (T));
10127 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10128 Set_Etype (Def_Id, Base_Type (T));
10130 if Constraint_OK then
10131 Set_First_Index (Def_Id, First (Constraints (C)));
10133 Set_First_Index (Def_Id, First_Index (T));
10136 Set_Is_Constrained (Def_Id, True);
10137 Set_Is_Aliased (Def_Id, Is_Aliased (T));
10138 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10140 Set_Is_Private_Composite (Def_Id, Is_Private_Composite (T));
10141 Set_Is_Limited_Composite (Def_Id, Is_Limited_Composite (T));
10143 -- A subtype does not inherit the packed_array_type of is parent. We
10144 -- need to initialize the attribute because if Def_Id is previously
10145 -- analyzed through a limited_with clause, it will have the attributes
10146 -- of an incomplete type, one of which is an Elist that overlaps the
10147 -- Packed_Array_Type field.
10149 Set_Packed_Array_Type (Def_Id, Empty);
10151 -- Build a freeze node if parent still needs one. Also make sure that
10152 -- the Depends_On_Private status is set because the subtype will need
10153 -- reprocessing at the time the base type does, and also we must set a
10154 -- conditional delay.
10156 Set_Depends_On_Private (Def_Id, Depends_On_Private (T));
10157 Conditional_Delay (Def_Id, T);
10158 end Constrain_Array;
10160 ------------------------------
10161 -- Constrain_Component_Type --
10162 ------------------------------
10164 function Constrain_Component_Type
10166 Constrained_Typ : Entity_Id;
10167 Related_Node : Node_Id;
10169 Constraints : Elist_Id) return Entity_Id
10171 Loc : constant Source_Ptr := Sloc (Constrained_Typ);
10172 Compon_Type : constant Entity_Id := Etype (Comp);
10174 function Build_Constrained_Array_Type
10175 (Old_Type : Entity_Id) return Entity_Id;
10176 -- If Old_Type is an array type, one of whose indices is constrained
10177 -- by a discriminant, build an Itype whose constraint replaces the
10178 -- discriminant with its value in the constraint.
10180 function Build_Constrained_Discriminated_Type
10181 (Old_Type : Entity_Id) return Entity_Id;
10182 -- Ditto for record components
10184 function Build_Constrained_Access_Type
10185 (Old_Type : Entity_Id) return Entity_Id;
10186 -- Ditto for access types. Makes use of previous two functions, to
10187 -- constrain designated type.
10189 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id;
10190 -- T is an array or discriminated type, C is a list of constraints
10191 -- that apply to T. This routine builds the constrained subtype.
10193 function Is_Discriminant (Expr : Node_Id) return Boolean;
10194 -- Returns True if Expr is a discriminant
10196 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id;
10197 -- Find the value of discriminant Discrim in Constraint
10199 -----------------------------------
10200 -- Build_Constrained_Access_Type --
10201 -----------------------------------
10203 function Build_Constrained_Access_Type
10204 (Old_Type : Entity_Id) return Entity_Id
10206 Desig_Type : constant Entity_Id := Designated_Type (Old_Type);
10208 Desig_Subtype : Entity_Id;
10212 -- if the original access type was not embedded in the enclosing
10213 -- type definition, there is no need to produce a new access
10214 -- subtype. In fact every access type with an explicit constraint
10215 -- generates an itype whose scope is the enclosing record.
10217 if not Is_Type (Scope (Old_Type)) then
10220 elsif Is_Array_Type (Desig_Type) then
10221 Desig_Subtype := Build_Constrained_Array_Type (Desig_Type);
10223 elsif Has_Discriminants (Desig_Type) then
10225 -- This may be an access type to an enclosing record type for
10226 -- which we are constructing the constrained components. Return
10227 -- the enclosing record subtype. This is not always correct,
10228 -- but avoids infinite recursion. ???
10230 Desig_Subtype := Any_Type;
10232 for J in reverse 0 .. Scope_Stack.Last loop
10233 Scop := Scope_Stack.Table (J).Entity;
10236 and then Base_Type (Scop) = Base_Type (Desig_Type)
10238 Desig_Subtype := Scop;
10241 exit when not Is_Type (Scop);
10244 if Desig_Subtype = Any_Type then
10246 Build_Constrained_Discriminated_Type (Desig_Type);
10253 if Desig_Subtype /= Desig_Type then
10255 -- The Related_Node better be here or else we won't be able
10256 -- to attach new itypes to a node in the tree.
10258 pragma Assert (Present (Related_Node));
10260 Itype := Create_Itype (E_Access_Subtype, Related_Node);
10262 Set_Etype (Itype, Base_Type (Old_Type));
10263 Set_Size_Info (Itype, (Old_Type));
10264 Set_Directly_Designated_Type (Itype, Desig_Subtype);
10265 Set_Depends_On_Private (Itype, Has_Private_Component
10267 Set_Is_Access_Constant (Itype, Is_Access_Constant
10270 -- The new itype needs freezing when it depends on a not frozen
10271 -- type and the enclosing subtype needs freezing.
10273 if Has_Delayed_Freeze (Constrained_Typ)
10274 and then not Is_Frozen (Constrained_Typ)
10276 Conditional_Delay (Itype, Base_Type (Old_Type));
10284 end Build_Constrained_Access_Type;
10286 ----------------------------------
10287 -- Build_Constrained_Array_Type --
10288 ----------------------------------
10290 function Build_Constrained_Array_Type
10291 (Old_Type : Entity_Id) return Entity_Id
10295 Old_Index : Node_Id;
10296 Range_Node : Node_Id;
10297 Constr_List : List_Id;
10299 Need_To_Create_Itype : Boolean := False;
10302 Old_Index := First_Index (Old_Type);
10303 while Present (Old_Index) loop
10304 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
10306 if Is_Discriminant (Lo_Expr)
10307 or else Is_Discriminant (Hi_Expr)
10309 Need_To_Create_Itype := True;
10312 Next_Index (Old_Index);
10315 if Need_To_Create_Itype then
10316 Constr_List := New_List;
10318 Old_Index := First_Index (Old_Type);
10319 while Present (Old_Index) loop
10320 Get_Index_Bounds (Old_Index, Lo_Expr, Hi_Expr);
10322 if Is_Discriminant (Lo_Expr) then
10323 Lo_Expr := Get_Discr_Value (Lo_Expr);
10326 if Is_Discriminant (Hi_Expr) then
10327 Hi_Expr := Get_Discr_Value (Hi_Expr);
10332 (Loc, New_Copy_Tree (Lo_Expr), New_Copy_Tree (Hi_Expr));
10334 Append (Range_Node, To => Constr_List);
10336 Next_Index (Old_Index);
10339 return Build_Subtype (Old_Type, Constr_List);
10344 end Build_Constrained_Array_Type;
10346 ------------------------------------------
10347 -- Build_Constrained_Discriminated_Type --
10348 ------------------------------------------
10350 function Build_Constrained_Discriminated_Type
10351 (Old_Type : Entity_Id) return Entity_Id
10354 Constr_List : List_Id;
10355 Old_Constraint : Elmt_Id;
10357 Need_To_Create_Itype : Boolean := False;
10360 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
10361 while Present (Old_Constraint) loop
10362 Expr := Node (Old_Constraint);
10364 if Is_Discriminant (Expr) then
10365 Need_To_Create_Itype := True;
10368 Next_Elmt (Old_Constraint);
10371 if Need_To_Create_Itype then
10372 Constr_List := New_List;
10374 Old_Constraint := First_Elmt (Discriminant_Constraint (Old_Type));
10375 while Present (Old_Constraint) loop
10376 Expr := Node (Old_Constraint);
10378 if Is_Discriminant (Expr) then
10379 Expr := Get_Discr_Value (Expr);
10382 Append (New_Copy_Tree (Expr), To => Constr_List);
10384 Next_Elmt (Old_Constraint);
10387 return Build_Subtype (Old_Type, Constr_List);
10392 end Build_Constrained_Discriminated_Type;
10394 -------------------
10395 -- Build_Subtype --
10396 -------------------
10398 function Build_Subtype (T : Entity_Id; C : List_Id) return Entity_Id is
10400 Subtyp_Decl : Node_Id;
10401 Def_Id : Entity_Id;
10402 Btyp : Entity_Id := Base_Type (T);
10405 -- The Related_Node better be here or else we won't be able to
10406 -- attach new itypes to a node in the tree.
10408 pragma Assert (Present (Related_Node));
10410 -- If the view of the component's type is incomplete or private
10411 -- with unknown discriminants, then the constraint must be applied
10412 -- to the full type.
10414 if Has_Unknown_Discriminants (Btyp)
10415 and then Present (Underlying_Type (Btyp))
10417 Btyp := Underlying_Type (Btyp);
10421 Make_Subtype_Indication (Loc,
10422 Subtype_Mark => New_Occurrence_Of (Btyp, Loc),
10423 Constraint => Make_Index_Or_Discriminant_Constraint (Loc, C));
10425 Def_Id := Create_Itype (Ekind (T), Related_Node);
10428 Make_Subtype_Declaration (Loc,
10429 Defining_Identifier => Def_Id,
10430 Subtype_Indication => Indic);
10432 Set_Parent (Subtyp_Decl, Parent (Related_Node));
10434 -- Itypes must be analyzed with checks off (see package Itypes)
10436 Analyze (Subtyp_Decl, Suppress => All_Checks);
10441 ---------------------
10442 -- Get_Discr_Value --
10443 ---------------------
10445 function Get_Discr_Value (Discrim : Entity_Id) return Node_Id is
10450 -- The discriminant may be declared for the type, in which case we
10451 -- find it by iterating over the list of discriminants. If the
10452 -- discriminant is inherited from a parent type, it appears as the
10453 -- corresponding discriminant of the current type. This will be the
10454 -- case when constraining an inherited component whose constraint is
10455 -- given by a discriminant of the parent.
10457 D := First_Discriminant (Typ);
10458 E := First_Elmt (Constraints);
10460 while Present (D) loop
10461 if D = Entity (Discrim)
10462 or else D = CR_Discriminant (Entity (Discrim))
10463 or else Corresponding_Discriminant (D) = Entity (Discrim)
10468 Next_Discriminant (D);
10472 -- The corresponding_Discriminant mechanism is incomplete, because
10473 -- the correspondence between new and old discriminants is not one
10474 -- to one: one new discriminant can constrain several old ones. In
10475 -- that case, scan sequentially the stored_constraint, the list of
10476 -- discriminants of the parents, and the constraints.
10477 -- Previous code checked for the present of the Stored_Constraint
10478 -- list for the derived type, but did not use it at all. Should it
10479 -- be present when the component is a discriminated task type?
10481 if Is_Derived_Type (Typ)
10482 and then Scope (Entity (Discrim)) = Etype (Typ)
10484 D := First_Discriminant (Etype (Typ));
10485 E := First_Elmt (Constraints);
10486 while Present (D) loop
10487 if D = Entity (Discrim) then
10491 Next_Discriminant (D);
10496 -- Something is wrong if we did not find the value
10498 raise Program_Error;
10499 end Get_Discr_Value;
10501 ---------------------
10502 -- Is_Discriminant --
10503 ---------------------
10505 function Is_Discriminant (Expr : Node_Id) return Boolean is
10506 Discrim_Scope : Entity_Id;
10509 if Denotes_Discriminant (Expr) then
10510 Discrim_Scope := Scope (Entity (Expr));
10512 -- Either we have a reference to one of Typ's discriminants,
10514 pragma Assert (Discrim_Scope = Typ
10516 -- or to the discriminants of the parent type, in the case
10517 -- of a derivation of a tagged type with variants.
10519 or else Discrim_Scope = Etype (Typ)
10520 or else Full_View (Discrim_Scope) = Etype (Typ)
10522 -- or same as above for the case where the discriminants
10523 -- were declared in Typ's private view.
10525 or else (Is_Private_Type (Discrim_Scope)
10526 and then Chars (Discrim_Scope) = Chars (Typ))
10528 -- or else we are deriving from the full view and the
10529 -- discriminant is declared in the private entity.
10531 or else (Is_Private_Type (Typ)
10532 and then Chars (Discrim_Scope) = Chars (Typ))
10534 -- Or we are constrained the corresponding record of a
10535 -- synchronized type that completes a private declaration.
10537 or else (Is_Concurrent_Record_Type (Typ)
10539 Corresponding_Concurrent_Type (Typ) = Discrim_Scope)
10541 -- or we have a class-wide type, in which case make sure the
10542 -- discriminant found belongs to the root type.
10544 or else (Is_Class_Wide_Type (Typ)
10545 and then Etype (Typ) = Discrim_Scope));
10550 -- In all other cases we have something wrong
10553 end Is_Discriminant;
10555 -- Start of processing for Constrain_Component_Type
10558 if Nkind (Parent (Comp)) = N_Component_Declaration
10559 and then Comes_From_Source (Parent (Comp))
10560 and then Comes_From_Source
10561 (Subtype_Indication (Component_Definition (Parent (Comp))))
10564 (Subtype_Indication (Component_Definition (Parent (Comp))))
10566 return Compon_Type;
10568 elsif Is_Array_Type (Compon_Type) then
10569 return Build_Constrained_Array_Type (Compon_Type);
10571 elsif Has_Discriminants (Compon_Type) then
10572 return Build_Constrained_Discriminated_Type (Compon_Type);
10574 elsif Is_Access_Type (Compon_Type) then
10575 return Build_Constrained_Access_Type (Compon_Type);
10578 return Compon_Type;
10580 end Constrain_Component_Type;
10582 --------------------------
10583 -- Constrain_Concurrent --
10584 --------------------------
10586 -- For concurrent types, the associated record value type carries the same
10587 -- discriminants, so when we constrain a concurrent type, we must constrain
10588 -- the corresponding record type as well.
10590 procedure Constrain_Concurrent
10591 (Def_Id : in out Entity_Id;
10593 Related_Nod : Node_Id;
10594 Related_Id : Entity_Id;
10595 Suffix : Character)
10597 T_Ent : Entity_Id := Entity (Subtype_Mark (SI));
10601 if Ekind (T_Ent) in Access_Kind then
10602 T_Ent := Designated_Type (T_Ent);
10605 T_Val := Corresponding_Record_Type (T_Ent);
10607 if Present (T_Val) then
10609 if No (Def_Id) then
10610 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
10613 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
10615 Set_Depends_On_Private (Def_Id, Has_Private_Component (Def_Id));
10616 Set_Corresponding_Record_Type (Def_Id,
10617 Constrain_Corresponding_Record
10618 (Def_Id, T_Val, Related_Nod, Related_Id));
10621 -- If there is no associated record, expansion is disabled and this
10622 -- is a generic context. Create a subtype in any case, so that
10623 -- semantic analysis can proceed.
10625 if No (Def_Id) then
10626 Def_Id := Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
10629 Constrain_Discriminated_Type (Def_Id, SI, Related_Nod);
10631 end Constrain_Concurrent;
10633 ------------------------------------
10634 -- Constrain_Corresponding_Record --
10635 ------------------------------------
10637 function Constrain_Corresponding_Record
10638 (Prot_Subt : Entity_Id;
10639 Corr_Rec : Entity_Id;
10640 Related_Nod : Node_Id;
10641 Related_Id : Entity_Id) return Entity_Id
10643 T_Sub : constant Entity_Id :=
10644 Create_Itype (E_Record_Subtype, Related_Nod, Related_Id, 'V');
10647 Set_Etype (T_Sub, Corr_Rec);
10648 Set_Has_Discriminants (T_Sub, Has_Discriminants (Prot_Subt));
10649 Set_Is_Constrained (T_Sub, True);
10650 Set_First_Entity (T_Sub, First_Entity (Corr_Rec));
10651 Set_Last_Entity (T_Sub, Last_Entity (Corr_Rec));
10653 -- As elsewhere, we do not want to create a freeze node for this itype
10654 -- if it is created for a constrained component of an enclosing record
10655 -- because references to outer discriminants will appear out of scope.
10657 if Ekind (Scope (Prot_Subt)) /= E_Record_Type then
10658 Conditional_Delay (T_Sub, Corr_Rec);
10660 Set_Is_Frozen (T_Sub);
10663 if Has_Discriminants (Prot_Subt) then -- False only if errors.
10664 Set_Discriminant_Constraint
10665 (T_Sub, Discriminant_Constraint (Prot_Subt));
10666 Set_Stored_Constraint_From_Discriminant_Constraint (T_Sub);
10667 Create_Constrained_Components
10668 (T_Sub, Related_Nod, Corr_Rec, Discriminant_Constraint (T_Sub));
10671 Set_Depends_On_Private (T_Sub, Has_Private_Component (T_Sub));
10674 end Constrain_Corresponding_Record;
10676 -----------------------
10677 -- Constrain_Decimal --
10678 -----------------------
10680 procedure Constrain_Decimal (Def_Id : Node_Id; S : Node_Id) is
10681 T : constant Entity_Id := Entity (Subtype_Mark (S));
10682 C : constant Node_Id := Constraint (S);
10683 Loc : constant Source_Ptr := Sloc (C);
10684 Range_Expr : Node_Id;
10685 Digits_Expr : Node_Id;
10690 Set_Ekind (Def_Id, E_Decimal_Fixed_Point_Subtype);
10692 if Nkind (C) = N_Range_Constraint then
10693 Range_Expr := Range_Expression (C);
10694 Digits_Val := Digits_Value (T);
10697 pragma Assert (Nkind (C) = N_Digits_Constraint);
10698 Digits_Expr := Digits_Expression (C);
10699 Analyze_And_Resolve (Digits_Expr, Any_Integer);
10701 Check_Digits_Expression (Digits_Expr);
10702 Digits_Val := Expr_Value (Digits_Expr);
10704 if Digits_Val > Digits_Value (T) then
10706 ("digits expression is incompatible with subtype", C);
10707 Digits_Val := Digits_Value (T);
10710 if Present (Range_Constraint (C)) then
10711 Range_Expr := Range_Expression (Range_Constraint (C));
10713 Range_Expr := Empty;
10717 Set_Etype (Def_Id, Base_Type (T));
10718 Set_Size_Info (Def_Id, (T));
10719 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10720 Set_Delta_Value (Def_Id, Delta_Value (T));
10721 Set_Scale_Value (Def_Id, Scale_Value (T));
10722 Set_Small_Value (Def_Id, Small_Value (T));
10723 Set_Machine_Radix_10 (Def_Id, Machine_Radix_10 (T));
10724 Set_Digits_Value (Def_Id, Digits_Val);
10726 -- Manufacture range from given digits value if no range present
10728 if No (Range_Expr) then
10729 Bound_Val := (Ureal_10 ** Digits_Val - Ureal_1) * Small_Value (T);
10733 Convert_To (T, Make_Real_Literal (Loc, (-Bound_Val))),
10735 Convert_To (T, Make_Real_Literal (Loc, Bound_Val)));
10738 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expr, T);
10739 Set_Discrete_RM_Size (Def_Id);
10741 -- Unconditionally delay the freeze, since we cannot set size
10742 -- information in all cases correctly until the freeze point.
10744 Set_Has_Delayed_Freeze (Def_Id);
10745 end Constrain_Decimal;
10747 ----------------------------------
10748 -- Constrain_Discriminated_Type --
10749 ----------------------------------
10751 procedure Constrain_Discriminated_Type
10752 (Def_Id : Entity_Id;
10754 Related_Nod : Node_Id;
10755 For_Access : Boolean := False)
10757 E : constant Entity_Id := Entity (Subtype_Mark (S));
10760 Elist : Elist_Id := New_Elmt_List;
10762 procedure Fixup_Bad_Constraint;
10763 -- This is called after finding a bad constraint, and after having
10764 -- posted an appropriate error message. The mission is to leave the
10765 -- entity T in as reasonable state as possible!
10767 --------------------------
10768 -- Fixup_Bad_Constraint --
10769 --------------------------
10771 procedure Fixup_Bad_Constraint is
10773 -- Set a reasonable Ekind for the entity. For an incomplete type,
10774 -- we can't do much, but for other types, we can set the proper
10775 -- corresponding subtype kind.
10777 if Ekind (T) = E_Incomplete_Type then
10778 Set_Ekind (Def_Id, Ekind (T));
10780 Set_Ekind (Def_Id, Subtype_Kind (Ekind (T)));
10783 -- Set Etype to the known type, to reduce chances of cascaded errors
10785 Set_Etype (Def_Id, E);
10786 Set_Error_Posted (Def_Id);
10787 end Fixup_Bad_Constraint;
10789 -- Start of processing for Constrain_Discriminated_Type
10792 C := Constraint (S);
10794 -- A discriminant constraint is only allowed in a subtype indication,
10795 -- after a subtype mark. This subtype mark must denote either a type
10796 -- with discriminants, or an access type whose designated type is a
10797 -- type with discriminants. A discriminant constraint specifies the
10798 -- values of these discriminants (RM 3.7.2(5)).
10800 T := Base_Type (Entity (Subtype_Mark (S)));
10802 if Ekind (T) in Access_Kind then
10803 T := Designated_Type (T);
10806 -- Ada 2005 (AI-412): Constrained incomplete subtypes are illegal.
10807 -- Avoid generating an error for access-to-incomplete subtypes.
10809 if Ada_Version >= Ada_05
10810 and then Ekind (T) = E_Incomplete_Type
10811 and then Nkind (Parent (S)) = N_Subtype_Declaration
10812 and then not Is_Itype (Def_Id)
10814 -- A little sanity check, emit an error message if the type
10815 -- has discriminants to begin with. Type T may be a regular
10816 -- incomplete type or imported via a limited with clause.
10818 if Has_Discriminants (T)
10820 (From_With_Type (T)
10821 and then Present (Non_Limited_View (T))
10822 and then Nkind (Parent (Non_Limited_View (T))) =
10823 N_Full_Type_Declaration
10824 and then Present (Discriminant_Specifications
10825 (Parent (Non_Limited_View (T)))))
10828 ("(Ada 2005) incomplete subtype may not be constrained", C);
10831 ("invalid constraint: type has no discriminant", C);
10834 Fixup_Bad_Constraint;
10837 -- Check that the type has visible discriminants. The type may be
10838 -- a private type with unknown discriminants whose full view has
10839 -- discriminants which are invisible.
10841 elsif not Has_Discriminants (T)
10843 (Has_Unknown_Discriminants (T)
10844 and then Is_Private_Type (T))
10846 Error_Msg_N ("invalid constraint: type has no discriminant", C);
10847 Fixup_Bad_Constraint;
10850 elsif Is_Constrained (E)
10851 or else (Ekind (E) = E_Class_Wide_Subtype
10852 and then Present (Discriminant_Constraint (E)))
10854 Error_Msg_N ("type is already constrained", Subtype_Mark (S));
10855 Fixup_Bad_Constraint;
10859 -- T may be an unconstrained subtype (e.g. a generic actual).
10860 -- Constraint applies to the base type.
10862 T := Base_Type (T);
10864 Elist := Build_Discriminant_Constraints (T, S);
10866 -- If the list returned was empty we had an error in building the
10867 -- discriminant constraint. We have also already signalled an error
10868 -- in the incomplete type case
10870 if Is_Empty_Elmt_List (Elist) then
10871 Fixup_Bad_Constraint;
10875 Build_Discriminated_Subtype (T, Def_Id, Elist, Related_Nod, For_Access);
10876 end Constrain_Discriminated_Type;
10878 ---------------------------
10879 -- Constrain_Enumeration --
10880 ---------------------------
10882 procedure Constrain_Enumeration (Def_Id : Node_Id; S : Node_Id) is
10883 T : constant Entity_Id := Entity (Subtype_Mark (S));
10884 C : constant Node_Id := Constraint (S);
10887 Set_Ekind (Def_Id, E_Enumeration_Subtype);
10889 Set_First_Literal (Def_Id, First_Literal (Base_Type (T)));
10891 Set_Etype (Def_Id, Base_Type (T));
10892 Set_Size_Info (Def_Id, (T));
10893 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10894 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
10896 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
10898 Set_Discrete_RM_Size (Def_Id);
10899 end Constrain_Enumeration;
10901 ----------------------
10902 -- Constrain_Float --
10903 ----------------------
10905 procedure Constrain_Float (Def_Id : Node_Id; S : Node_Id) is
10906 T : constant Entity_Id := Entity (Subtype_Mark (S));
10912 Set_Ekind (Def_Id, E_Floating_Point_Subtype);
10914 Set_Etype (Def_Id, Base_Type (T));
10915 Set_Size_Info (Def_Id, (T));
10916 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
10918 -- Process the constraint
10920 C := Constraint (S);
10922 -- Digits constraint present
10924 if Nkind (C) = N_Digits_Constraint then
10925 Check_Restriction (No_Obsolescent_Features, C);
10927 if Warn_On_Obsolescent_Feature then
10929 ("subtype digits constraint is an " &
10930 "obsolescent feature (RM J.3(8))?", C);
10933 D := Digits_Expression (C);
10934 Analyze_And_Resolve (D, Any_Integer);
10935 Check_Digits_Expression (D);
10936 Set_Digits_Value (Def_Id, Expr_Value (D));
10938 -- Check that digits value is in range. Obviously we can do this
10939 -- at compile time, but it is strictly a runtime check, and of
10940 -- course there is an ACVC test that checks this!
10942 if Digits_Value (Def_Id) > Digits_Value (T) then
10943 Error_Msg_Uint_1 := Digits_Value (T);
10944 Error_Msg_N ("?digits value is too large, maximum is ^", D);
10946 Make_Raise_Constraint_Error (Sloc (D),
10947 Reason => CE_Range_Check_Failed);
10948 Insert_Action (Declaration_Node (Def_Id), Rais);
10951 C := Range_Constraint (C);
10953 -- No digits constraint present
10956 Set_Digits_Value (Def_Id, Digits_Value (T));
10959 -- Range constraint present
10961 if Nkind (C) = N_Range_Constraint then
10962 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
10964 -- No range constraint present
10967 pragma Assert (No (C));
10968 Set_Scalar_Range (Def_Id, Scalar_Range (T));
10971 Set_Is_Constrained (Def_Id);
10972 end Constrain_Float;
10974 ---------------------
10975 -- Constrain_Index --
10976 ---------------------
10978 procedure Constrain_Index
10981 Related_Nod : Node_Id;
10982 Related_Id : Entity_Id;
10983 Suffix : Character;
10984 Suffix_Index : Nat)
10986 Def_Id : Entity_Id;
10987 R : Node_Id := Empty;
10988 T : constant Entity_Id := Etype (Index);
10991 if Nkind (S) = N_Range
10993 (Nkind (S) = N_Attribute_Reference
10994 and then Attribute_Name (S) = Name_Range)
10996 -- A Range attribute will transformed into N_Range by Resolve
11002 Process_Range_Expr_In_Decl (R, T, Empty_List);
11004 if not Error_Posted (S)
11006 (Nkind (S) /= N_Range
11007 or else not Covers (T, (Etype (Low_Bound (S))))
11008 or else not Covers (T, (Etype (High_Bound (S)))))
11010 if Base_Type (T) /= Any_Type
11011 and then Etype (Low_Bound (S)) /= Any_Type
11012 and then Etype (High_Bound (S)) /= Any_Type
11014 Error_Msg_N ("range expected", S);
11018 elsif Nkind (S) = N_Subtype_Indication then
11020 -- The parser has verified that this is a discrete indication
11022 Resolve_Discrete_Subtype_Indication (S, T);
11023 R := Range_Expression (Constraint (S));
11025 elsif Nkind (S) = N_Discriminant_Association then
11027 -- Syntactically valid in subtype indication
11029 Error_Msg_N ("invalid index constraint", S);
11030 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11033 -- Subtype_Mark case, no anonymous subtypes to construct
11038 if Is_Entity_Name (S) then
11039 if not Is_Type (Entity (S)) then
11040 Error_Msg_N ("expect subtype mark for index constraint", S);
11042 elsif Base_Type (Entity (S)) /= Base_Type (T) then
11043 Wrong_Type (S, Base_Type (T));
11049 Error_Msg_N ("invalid index constraint", S);
11050 Rewrite (S, New_Occurrence_Of (T, Sloc (S)));
11056 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix, Suffix_Index);
11058 Set_Etype (Def_Id, Base_Type (T));
11060 if Is_Modular_Integer_Type (T) then
11061 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11063 elsif Is_Integer_Type (T) then
11064 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11067 Set_Ekind (Def_Id, E_Enumeration_Subtype);
11068 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
11069 Set_First_Literal (Def_Id, First_Literal (T));
11072 Set_Size_Info (Def_Id, (T));
11073 Set_RM_Size (Def_Id, RM_Size (T));
11074 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11076 Set_Scalar_Range (Def_Id, R);
11078 Set_Etype (S, Def_Id);
11079 Set_Discrete_RM_Size (Def_Id);
11080 end Constrain_Index;
11082 -----------------------
11083 -- Constrain_Integer --
11084 -----------------------
11086 procedure Constrain_Integer (Def_Id : Node_Id; S : Node_Id) is
11087 T : constant Entity_Id := Entity (Subtype_Mark (S));
11088 C : constant Node_Id := Constraint (S);
11091 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11093 if Is_Modular_Integer_Type (T) then
11094 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
11096 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
11099 Set_Etype (Def_Id, Base_Type (T));
11100 Set_Size_Info (Def_Id, (T));
11101 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11102 Set_Discrete_RM_Size (Def_Id);
11103 end Constrain_Integer;
11105 ------------------------------
11106 -- Constrain_Ordinary_Fixed --
11107 ------------------------------
11109 procedure Constrain_Ordinary_Fixed (Def_Id : Node_Id; S : Node_Id) is
11110 T : constant Entity_Id := Entity (Subtype_Mark (S));
11116 Set_Ekind (Def_Id, E_Ordinary_Fixed_Point_Subtype);
11117 Set_Etype (Def_Id, Base_Type (T));
11118 Set_Size_Info (Def_Id, (T));
11119 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
11120 Set_Small_Value (Def_Id, Small_Value (T));
11122 -- Process the constraint
11124 C := Constraint (S);
11126 -- Delta constraint present
11128 if Nkind (C) = N_Delta_Constraint then
11129 Check_Restriction (No_Obsolescent_Features, C);
11131 if Warn_On_Obsolescent_Feature then
11133 ("subtype delta constraint is an " &
11134 "obsolescent feature (RM J.3(7))?");
11137 D := Delta_Expression (C);
11138 Analyze_And_Resolve (D, Any_Real);
11139 Check_Delta_Expression (D);
11140 Set_Delta_Value (Def_Id, Expr_Value_R (D));
11142 -- Check that delta value is in range. Obviously we can do this
11143 -- at compile time, but it is strictly a runtime check, and of
11144 -- course there is an ACVC test that checks this!
11146 if Delta_Value (Def_Id) < Delta_Value (T) then
11147 Error_Msg_N ("?delta value is too small", D);
11149 Make_Raise_Constraint_Error (Sloc (D),
11150 Reason => CE_Range_Check_Failed);
11151 Insert_Action (Declaration_Node (Def_Id), Rais);
11154 C := Range_Constraint (C);
11156 -- No delta constraint present
11159 Set_Delta_Value (Def_Id, Delta_Value (T));
11162 -- Range constraint present
11164 if Nkind (C) = N_Range_Constraint then
11165 Set_Scalar_Range_For_Subtype (Def_Id, Range_Expression (C), T);
11167 -- No range constraint present
11170 pragma Assert (No (C));
11171 Set_Scalar_Range (Def_Id, Scalar_Range (T));
11175 Set_Discrete_RM_Size (Def_Id);
11177 -- Unconditionally delay the freeze, since we cannot set size
11178 -- information in all cases correctly until the freeze point.
11180 Set_Has_Delayed_Freeze (Def_Id);
11181 end Constrain_Ordinary_Fixed;
11183 -----------------------
11184 -- Contain_Interface --
11185 -----------------------
11187 function Contain_Interface
11188 (Iface : Entity_Id;
11189 Ifaces : Elist_Id) return Boolean
11191 Iface_Elmt : Elmt_Id;
11194 if Present (Ifaces) then
11195 Iface_Elmt := First_Elmt (Ifaces);
11196 while Present (Iface_Elmt) loop
11197 if Node (Iface_Elmt) = Iface then
11201 Next_Elmt (Iface_Elmt);
11206 end Contain_Interface;
11208 ---------------------------
11209 -- Convert_Scalar_Bounds --
11210 ---------------------------
11212 procedure Convert_Scalar_Bounds
11214 Parent_Type : Entity_Id;
11215 Derived_Type : Entity_Id;
11218 Implicit_Base : constant Entity_Id := Base_Type (Derived_Type);
11225 Lo := Build_Scalar_Bound
11226 (Type_Low_Bound (Derived_Type),
11227 Parent_Type, Implicit_Base);
11229 Hi := Build_Scalar_Bound
11230 (Type_High_Bound (Derived_Type),
11231 Parent_Type, Implicit_Base);
11238 Set_Includes_Infinities (Rng, Has_Infinities (Derived_Type));
11240 Set_Parent (Rng, N);
11241 Set_Scalar_Range (Derived_Type, Rng);
11243 -- Analyze the bounds
11245 Analyze_And_Resolve (Lo, Implicit_Base);
11246 Analyze_And_Resolve (Hi, Implicit_Base);
11248 -- Analyze the range itself, except that we do not analyze it if
11249 -- the bounds are real literals, and we have a fixed-point type.
11250 -- The reason for this is that we delay setting the bounds in this
11251 -- case till we know the final Small and Size values (see circuit
11252 -- in Freeze.Freeze_Fixed_Point_Type for further details).
11254 if Is_Fixed_Point_Type (Parent_Type)
11255 and then Nkind (Lo) = N_Real_Literal
11256 and then Nkind (Hi) = N_Real_Literal
11260 -- Here we do the analysis of the range
11262 -- Note: we do this manually, since if we do a normal Analyze and
11263 -- Resolve call, there are problems with the conversions used for
11264 -- the derived type range.
11267 Set_Etype (Rng, Implicit_Base);
11268 Set_Analyzed (Rng, True);
11270 end Convert_Scalar_Bounds;
11272 -------------------
11273 -- Copy_And_Swap --
11274 -------------------
11276 procedure Copy_And_Swap (Priv, Full : Entity_Id) is
11278 -- Initialize new full declaration entity by copying the pertinent
11279 -- fields of the corresponding private declaration entity.
11281 -- We temporarily set Ekind to a value appropriate for a type to
11282 -- avoid assert failures in Einfo from checking for setting type
11283 -- attributes on something that is not a type. Ekind (Priv) is an
11284 -- appropriate choice, since it allowed the attributes to be set
11285 -- in the first place. This Ekind value will be modified later.
11287 Set_Ekind (Full, Ekind (Priv));
11289 -- Also set Etype temporarily to Any_Type, again, in the absence
11290 -- of errors, it will be properly reset, and if there are errors,
11291 -- then we want a value of Any_Type to remain.
11293 Set_Etype (Full, Any_Type);
11295 -- Now start copying attributes
11297 Set_Has_Discriminants (Full, Has_Discriminants (Priv));
11299 if Has_Discriminants (Full) then
11300 Set_Discriminant_Constraint (Full, Discriminant_Constraint (Priv));
11301 Set_Stored_Constraint (Full, Stored_Constraint (Priv));
11304 Set_First_Rep_Item (Full, First_Rep_Item (Priv));
11305 Set_Homonym (Full, Homonym (Priv));
11306 Set_Is_Immediately_Visible (Full, Is_Immediately_Visible (Priv));
11307 Set_Is_Public (Full, Is_Public (Priv));
11308 Set_Is_Pure (Full, Is_Pure (Priv));
11309 Set_Is_Tagged_Type (Full, Is_Tagged_Type (Priv));
11310 Set_Has_Pragma_Unmodified (Full, Has_Pragma_Unmodified (Priv));
11311 Set_Has_Pragma_Unreferenced (Full, Has_Pragma_Unreferenced (Priv));
11312 Set_Has_Pragma_Unreferenced_Objects
11313 (Full, Has_Pragma_Unreferenced_Objects
11316 Conditional_Delay (Full, Priv);
11318 if Is_Tagged_Type (Full) then
11319 Set_Primitive_Operations (Full, Primitive_Operations (Priv));
11321 if Priv = Base_Type (Priv) then
11322 Set_Class_Wide_Type (Full, Class_Wide_Type (Priv));
11326 Set_Is_Volatile (Full, Is_Volatile (Priv));
11327 Set_Treat_As_Volatile (Full, Treat_As_Volatile (Priv));
11328 Set_Scope (Full, Scope (Priv));
11329 Set_Next_Entity (Full, Next_Entity (Priv));
11330 Set_First_Entity (Full, First_Entity (Priv));
11331 Set_Last_Entity (Full, Last_Entity (Priv));
11333 -- If access types have been recorded for later handling, keep them in
11334 -- the full view so that they get handled when the full view freeze
11335 -- node is expanded.
11337 if Present (Freeze_Node (Priv))
11338 and then Present (Access_Types_To_Process (Freeze_Node (Priv)))
11340 Ensure_Freeze_Node (Full);
11341 Set_Access_Types_To_Process
11342 (Freeze_Node (Full),
11343 Access_Types_To_Process (Freeze_Node (Priv)));
11346 -- Swap the two entities. Now Privat is the full type entity and Full is
11347 -- the private one. They will be swapped back at the end of the private
11348 -- part. This swapping ensures that the entity that is visible in the
11349 -- private part is the full declaration.
11351 Exchange_Entities (Priv, Full);
11352 Append_Entity (Full, Scope (Full));
11355 -------------------------------------
11356 -- Copy_Array_Base_Type_Attributes --
11357 -------------------------------------
11359 procedure Copy_Array_Base_Type_Attributes (T1, T2 : Entity_Id) is
11361 Set_Component_Alignment (T1, Component_Alignment (T2));
11362 Set_Component_Type (T1, Component_Type (T2));
11363 Set_Component_Size (T1, Component_Size (T2));
11364 Set_Has_Controlled_Component (T1, Has_Controlled_Component (T2));
11365 Set_Finalize_Storage_Only (T1, Finalize_Storage_Only (T2));
11366 Set_Has_Non_Standard_Rep (T1, Has_Non_Standard_Rep (T2));
11367 Set_Has_Task (T1, Has_Task (T2));
11368 Set_Is_Packed (T1, Is_Packed (T2));
11369 Set_Has_Aliased_Components (T1, Has_Aliased_Components (T2));
11370 Set_Has_Atomic_Components (T1, Has_Atomic_Components (T2));
11371 Set_Has_Volatile_Components (T1, Has_Volatile_Components (T2));
11372 end Copy_Array_Base_Type_Attributes;
11374 -----------------------------------
11375 -- Copy_Array_Subtype_Attributes --
11376 -----------------------------------
11378 procedure Copy_Array_Subtype_Attributes (T1, T2 : Entity_Id) is
11380 Set_Size_Info (T1, T2);
11382 Set_First_Index (T1, First_Index (T2));
11383 Set_Is_Aliased (T1, Is_Aliased (T2));
11384 Set_Is_Atomic (T1, Is_Atomic (T2));
11385 Set_Is_Volatile (T1, Is_Volatile (T2));
11386 Set_Treat_As_Volatile (T1, Treat_As_Volatile (T2));
11387 Set_Is_Constrained (T1, Is_Constrained (T2));
11388 Set_Depends_On_Private (T1, Has_Private_Component (T2));
11389 Set_First_Rep_Item (T1, First_Rep_Item (T2));
11390 Set_Convention (T1, Convention (T2));
11391 Set_Is_Limited_Composite (T1, Is_Limited_Composite (T2));
11392 Set_Is_Private_Composite (T1, Is_Private_Composite (T2));
11393 Set_Packed_Array_Type (T1, Packed_Array_Type (T2));
11394 end Copy_Array_Subtype_Attributes;
11396 -----------------------------------
11397 -- Create_Constrained_Components --
11398 -----------------------------------
11400 procedure Create_Constrained_Components
11402 Decl_Node : Node_Id;
11404 Constraints : Elist_Id)
11406 Loc : constant Source_Ptr := Sloc (Subt);
11407 Comp_List : constant Elist_Id := New_Elmt_List;
11408 Parent_Type : constant Entity_Id := Etype (Typ);
11409 Assoc_List : constant List_Id := New_List;
11410 Discr_Val : Elmt_Id;
11414 Is_Static : Boolean := True;
11416 procedure Collect_Fixed_Components (Typ : Entity_Id);
11417 -- Collect parent type components that do not appear in a variant part
11419 procedure Create_All_Components;
11420 -- Iterate over Comp_List to create the components of the subtype
11422 function Create_Component (Old_Compon : Entity_Id) return Entity_Id;
11423 -- Creates a new component from Old_Compon, copying all the fields from
11424 -- it, including its Etype, inserts the new component in the Subt entity
11425 -- chain and returns the new component.
11427 function Is_Variant_Record (T : Entity_Id) return Boolean;
11428 -- If true, and discriminants are static, collect only components from
11429 -- variants selected by discriminant values.
11431 ------------------------------
11432 -- Collect_Fixed_Components --
11433 ------------------------------
11435 procedure Collect_Fixed_Components (Typ : Entity_Id) is
11437 -- Build association list for discriminants, and find components of the
11438 -- variant part selected by the values of the discriminants.
11440 Old_C := First_Discriminant (Typ);
11441 Discr_Val := First_Elmt (Constraints);
11442 while Present (Old_C) loop
11443 Append_To (Assoc_List,
11444 Make_Component_Association (Loc,
11445 Choices => New_List (New_Occurrence_Of (Old_C, Loc)),
11446 Expression => New_Copy (Node (Discr_Val))));
11448 Next_Elmt (Discr_Val);
11449 Next_Discriminant (Old_C);
11452 -- The tag, and the possible parent and controller components
11453 -- are unconditionally in the subtype.
11455 if Is_Tagged_Type (Typ)
11456 or else Has_Controlled_Component (Typ)
11458 Old_C := First_Component (Typ);
11459 while Present (Old_C) loop
11460 if Chars ((Old_C)) = Name_uTag
11461 or else Chars ((Old_C)) = Name_uParent
11462 or else Chars ((Old_C)) = Name_uController
11464 Append_Elmt (Old_C, Comp_List);
11467 Next_Component (Old_C);
11470 end Collect_Fixed_Components;
11472 ---------------------------
11473 -- Create_All_Components --
11474 ---------------------------
11476 procedure Create_All_Components is
11480 Comp := First_Elmt (Comp_List);
11481 while Present (Comp) loop
11482 Old_C := Node (Comp);
11483 New_C := Create_Component (Old_C);
11487 Constrain_Component_Type
11488 (Old_C, Subt, Decl_Node, Typ, Constraints));
11489 Set_Is_Public (New_C, Is_Public (Subt));
11493 end Create_All_Components;
11495 ----------------------
11496 -- Create_Component --
11497 ----------------------
11499 function Create_Component (Old_Compon : Entity_Id) return Entity_Id is
11500 New_Compon : constant Entity_Id := New_Copy (Old_Compon);
11503 if Ekind (Old_Compon) = E_Discriminant
11504 and then Is_Completely_Hidden (Old_Compon)
11506 -- This is a shadow discriminant created for a discriminant of
11507 -- the parent type, which needs to be present in the subtype.
11508 -- Give the shadow discriminant an internal name that cannot
11509 -- conflict with that of visible components.
11511 Set_Chars (New_Compon, New_Internal_Name ('C'));
11514 -- Set the parent so we have a proper link for freezing etc. This is
11515 -- not a real parent pointer, since of course our parent does not own
11516 -- up to us and reference us, we are an illegitimate child of the
11517 -- original parent!
11519 Set_Parent (New_Compon, Parent (Old_Compon));
11521 -- If the old component's Esize was already determined and is a
11522 -- static value, then the new component simply inherits it. Otherwise
11523 -- the old component's size may require run-time determination, but
11524 -- the new component's size still might be statically determinable
11525 -- (if, for example it has a static constraint). In that case we want
11526 -- Layout_Type to recompute the component's size, so we reset its
11527 -- size and positional fields.
11529 if Frontend_Layout_On_Target
11530 and then not Known_Static_Esize (Old_Compon)
11532 Set_Esize (New_Compon, Uint_0);
11533 Init_Normalized_First_Bit (New_Compon);
11534 Init_Normalized_Position (New_Compon);
11535 Init_Normalized_Position_Max (New_Compon);
11538 -- We do not want this node marked as Comes_From_Source, since
11539 -- otherwise it would get first class status and a separate cross-
11540 -- reference line would be generated. Illegitimate children do not
11541 -- rate such recognition.
11543 Set_Comes_From_Source (New_Compon, False);
11545 -- But it is a real entity, and a birth certificate must be properly
11546 -- registered by entering it into the entity list.
11548 Enter_Name (New_Compon);
11551 end Create_Component;
11553 -----------------------
11554 -- Is_Variant_Record --
11555 -----------------------
11557 function Is_Variant_Record (T : Entity_Id) return Boolean is
11559 return Nkind (Parent (T)) = N_Full_Type_Declaration
11560 and then Nkind (Type_Definition (Parent (T))) = N_Record_Definition
11561 and then Present (Component_List (Type_Definition (Parent (T))))
11564 (Variant_Part (Component_List (Type_Definition (Parent (T)))));
11565 end Is_Variant_Record;
11567 -- Start of processing for Create_Constrained_Components
11570 pragma Assert (Subt /= Base_Type (Subt));
11571 pragma Assert (Typ = Base_Type (Typ));
11573 Set_First_Entity (Subt, Empty);
11574 Set_Last_Entity (Subt, Empty);
11576 -- Check whether constraint is fully static, in which case we can
11577 -- optimize the list of components.
11579 Discr_Val := First_Elmt (Constraints);
11580 while Present (Discr_Val) loop
11581 if not Is_OK_Static_Expression (Node (Discr_Val)) then
11582 Is_Static := False;
11586 Next_Elmt (Discr_Val);
11589 Set_Has_Static_Discriminants (Subt, Is_Static);
11593 -- Inherit the discriminants of the parent type
11595 Add_Discriminants : declare
11601 Old_C := First_Discriminant (Typ);
11603 while Present (Old_C) loop
11604 Num_Disc := Num_Disc + 1;
11605 New_C := Create_Component (Old_C);
11606 Set_Is_Public (New_C, Is_Public (Subt));
11607 Next_Discriminant (Old_C);
11610 -- For an untagged derived subtype, the number of discriminants may
11611 -- be smaller than the number of inherited discriminants, because
11612 -- several of them may be renamed by a single new discriminant or
11613 -- constrained. In this case, add the hidden discriminants back into
11614 -- the subtype, because they need to be present if the optimizer of
11615 -- the GCC 4.x back-end decides to break apart assignments between
11616 -- objects using the parent view into member-wise assignments.
11620 if Is_Derived_Type (Typ)
11621 and then not Is_Tagged_Type (Typ)
11623 Old_C := First_Stored_Discriminant (Typ);
11625 while Present (Old_C) loop
11626 Num_Gird := Num_Gird + 1;
11627 Next_Stored_Discriminant (Old_C);
11631 if Num_Gird > Num_Disc then
11633 -- Find out multiple uses of new discriminants, and add hidden
11634 -- components for the extra renamed discriminants. We recognize
11635 -- multiple uses through the Corresponding_Discriminant of a
11636 -- new discriminant: if it constrains several old discriminants,
11637 -- this field points to the last one in the parent type. The
11638 -- stored discriminants of the derived type have the same name
11639 -- as those of the parent.
11643 New_Discr : Entity_Id;
11644 Old_Discr : Entity_Id;
11647 Constr := First_Elmt (Stored_Constraint (Typ));
11648 Old_Discr := First_Stored_Discriminant (Typ);
11649 while Present (Constr) loop
11650 if Is_Entity_Name (Node (Constr))
11651 and then Ekind (Entity (Node (Constr))) = E_Discriminant
11653 New_Discr := Entity (Node (Constr));
11655 if Chars (Corresponding_Discriminant (New_Discr)) /=
11658 -- The new discriminant has been used to rename a
11659 -- subsequent old discriminant. Introduce a shadow
11660 -- component for the current old discriminant.
11662 New_C := Create_Component (Old_Discr);
11663 Set_Original_Record_Component (New_C, Old_Discr);
11667 -- The constraint has eliminated the old discriminant.
11668 -- Introduce a shadow component.
11670 New_C := Create_Component (Old_Discr);
11671 Set_Original_Record_Component (New_C, Old_Discr);
11674 Next_Elmt (Constr);
11675 Next_Stored_Discriminant (Old_Discr);
11679 end Add_Discriminants;
11682 and then Is_Variant_Record (Typ)
11684 Collect_Fixed_Components (Typ);
11686 Gather_Components (
11688 Component_List (Type_Definition (Parent (Typ))),
11689 Governed_By => Assoc_List,
11691 Report_Errors => Errors);
11692 pragma Assert (not Errors);
11694 Create_All_Components;
11696 -- If the subtype declaration is created for a tagged type derivation
11697 -- with constraints, we retrieve the record definition of the parent
11698 -- type to select the components of the proper variant.
11701 and then Is_Tagged_Type (Typ)
11702 and then Nkind (Parent (Typ)) = N_Full_Type_Declaration
11704 Nkind (Type_Definition (Parent (Typ))) = N_Derived_Type_Definition
11705 and then Is_Variant_Record (Parent_Type)
11707 Collect_Fixed_Components (Typ);
11709 Gather_Components (
11711 Component_List (Type_Definition (Parent (Parent_Type))),
11712 Governed_By => Assoc_List,
11714 Report_Errors => Errors);
11715 pragma Assert (not Errors);
11717 -- If the tagged derivation has a type extension, collect all the
11718 -- new components therein.
11721 (Record_Extension_Part (Type_Definition (Parent (Typ))))
11723 Old_C := First_Component (Typ);
11724 while Present (Old_C) loop
11725 if Original_Record_Component (Old_C) = Old_C
11726 and then Chars (Old_C) /= Name_uTag
11727 and then Chars (Old_C) /= Name_uParent
11728 and then Chars (Old_C) /= Name_uController
11730 Append_Elmt (Old_C, Comp_List);
11733 Next_Component (Old_C);
11737 Create_All_Components;
11740 -- If discriminants are not static, or if this is a multi-level type
11741 -- extension, we have to include all components of the parent type.
11743 Old_C := First_Component (Typ);
11744 while Present (Old_C) loop
11745 New_C := Create_Component (Old_C);
11749 Constrain_Component_Type
11750 (Old_C, Subt, Decl_Node, Typ, Constraints));
11751 Set_Is_Public (New_C, Is_Public (Subt));
11753 Next_Component (Old_C);
11758 end Create_Constrained_Components;
11760 ------------------------------------------
11761 -- Decimal_Fixed_Point_Type_Declaration --
11762 ------------------------------------------
11764 procedure Decimal_Fixed_Point_Type_Declaration
11768 Loc : constant Source_Ptr := Sloc (Def);
11769 Digs_Expr : constant Node_Id := Digits_Expression (Def);
11770 Delta_Expr : constant Node_Id := Delta_Expression (Def);
11771 Implicit_Base : Entity_Id;
11778 Check_Restriction (No_Fixed_Point, Def);
11780 -- Create implicit base type
11783 Create_Itype (E_Decimal_Fixed_Point_Type, Parent (Def), T, 'B');
11784 Set_Etype (Implicit_Base, Implicit_Base);
11786 -- Analyze and process delta expression
11788 Analyze_And_Resolve (Delta_Expr, Universal_Real);
11790 Check_Delta_Expression (Delta_Expr);
11791 Delta_Val := Expr_Value_R (Delta_Expr);
11793 -- Check delta is power of 10, and determine scale value from it
11799 Scale_Val := Uint_0;
11802 if Val < Ureal_1 then
11803 while Val < Ureal_1 loop
11804 Val := Val * Ureal_10;
11805 Scale_Val := Scale_Val + 1;
11808 if Scale_Val > 18 then
11809 Error_Msg_N ("scale exceeds maximum value of 18", Def);
11810 Scale_Val := UI_From_Int (+18);
11814 while Val > Ureal_1 loop
11815 Val := Val / Ureal_10;
11816 Scale_Val := Scale_Val - 1;
11819 if Scale_Val < -18 then
11820 Error_Msg_N ("scale is less than minimum value of -18", Def);
11821 Scale_Val := UI_From_Int (-18);
11825 if Val /= Ureal_1 then
11826 Error_Msg_N ("delta expression must be a power of 10", Def);
11827 Delta_Val := Ureal_10 ** (-Scale_Val);
11831 -- Set delta, scale and small (small = delta for decimal type)
11833 Set_Delta_Value (Implicit_Base, Delta_Val);
11834 Set_Scale_Value (Implicit_Base, Scale_Val);
11835 Set_Small_Value (Implicit_Base, Delta_Val);
11837 -- Analyze and process digits expression
11839 Analyze_And_Resolve (Digs_Expr, Any_Integer);
11840 Check_Digits_Expression (Digs_Expr);
11841 Digs_Val := Expr_Value (Digs_Expr);
11843 if Digs_Val > 18 then
11844 Digs_Val := UI_From_Int (+18);
11845 Error_Msg_N ("digits value out of range, maximum is 18", Digs_Expr);
11848 Set_Digits_Value (Implicit_Base, Digs_Val);
11849 Bound_Val := UR_From_Uint (10 ** Digs_Val - 1) * Delta_Val;
11851 -- Set range of base type from digits value for now. This will be
11852 -- expanded to represent the true underlying base range by Freeze.
11854 Set_Fixed_Range (Implicit_Base, Loc, -Bound_Val, Bound_Val);
11856 -- Note: We leave size as zero for now, size will be set at freeze
11857 -- time. We have to do this for ordinary fixed-point, because the size
11858 -- depends on the specified small, and we might as well do the same for
11859 -- decimal fixed-point.
11861 pragma Assert (Esize (Implicit_Base) = Uint_0);
11863 -- If there are bounds given in the declaration use them as the
11864 -- bounds of the first named subtype.
11866 if Present (Real_Range_Specification (Def)) then
11868 RRS : constant Node_Id := Real_Range_Specification (Def);
11869 Low : constant Node_Id := Low_Bound (RRS);
11870 High : constant Node_Id := High_Bound (RRS);
11875 Analyze_And_Resolve (Low, Any_Real);
11876 Analyze_And_Resolve (High, Any_Real);
11877 Check_Real_Bound (Low);
11878 Check_Real_Bound (High);
11879 Low_Val := Expr_Value_R (Low);
11880 High_Val := Expr_Value_R (High);
11882 if Low_Val < (-Bound_Val) then
11884 ("range low bound too small for digits value", Low);
11885 Low_Val := -Bound_Val;
11888 if High_Val > Bound_Val then
11890 ("range high bound too large for digits value", High);
11891 High_Val := Bound_Val;
11894 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
11897 -- If no explicit range, use range that corresponds to given
11898 -- digits value. This will end up as the final range for the
11902 Set_Fixed_Range (T, Loc, -Bound_Val, Bound_Val);
11905 -- Complete entity for first subtype
11907 Set_Ekind (T, E_Decimal_Fixed_Point_Subtype);
11908 Set_Etype (T, Implicit_Base);
11909 Set_Size_Info (T, Implicit_Base);
11910 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
11911 Set_Digits_Value (T, Digs_Val);
11912 Set_Delta_Value (T, Delta_Val);
11913 Set_Small_Value (T, Delta_Val);
11914 Set_Scale_Value (T, Scale_Val);
11915 Set_Is_Constrained (T);
11916 end Decimal_Fixed_Point_Type_Declaration;
11918 -----------------------------------
11919 -- Derive_Progenitor_Subprograms --
11920 -----------------------------------
11922 procedure Derive_Progenitor_Subprograms
11923 (Parent_Type : Entity_Id;
11924 Tagged_Type : Entity_Id)
11929 Iface_Elmt : Elmt_Id;
11930 Iface_Subp : Entity_Id;
11931 New_Subp : Entity_Id := Empty;
11932 Prim_Elmt : Elmt_Id;
11937 pragma Assert (Ada_Version >= Ada_05
11938 and then Is_Record_Type (Tagged_Type)
11939 and then Is_Tagged_Type (Tagged_Type)
11940 and then Has_Interfaces (Tagged_Type));
11942 -- Step 1: Transfer to the full-view primitives associated with the
11943 -- partial-view that cover interface primitives. Conceptually this
11944 -- work should be done later by Process_Full_View; done here to
11945 -- simplify its implementation at later stages. It can be safely
11946 -- done here because interfaces must be visible in the partial and
11947 -- private view (RM 7.3(7.3/2)).
11949 -- Small optimization: This work is only required if the parent is
11950 -- abstract. If the tagged type is not abstract, it cannot have
11951 -- abstract primitives (the only entities in the list of primitives of
11952 -- non-abstract tagged types that can reference abstract primitives
11953 -- through its Alias attribute are the internal entities that have
11954 -- attribute Interface_Alias, and these entities are generated later
11955 -- by Freeze_Record_Type).
11957 if In_Private_Part (Current_Scope)
11958 and then Is_Abstract_Type (Parent_Type)
11960 Elmt := First_Elmt (Primitive_Operations (Tagged_Type));
11961 while Present (Elmt) loop
11962 Subp := Node (Elmt);
11964 -- At this stage it is not possible to have entities in the list
11965 -- of primitives that have attribute Interface_Alias
11967 pragma Assert (No (Interface_Alias (Subp)));
11969 Typ := Find_Dispatching_Type (Ultimate_Alias (Subp));
11971 if Is_Interface (Typ) then
11972 E := Find_Primitive_Covering_Interface
11973 (Tagged_Type => Tagged_Type,
11974 Iface_Prim => Subp);
11977 and then Find_Dispatching_Type (Ultimate_Alias (E)) /= Typ
11979 Replace_Elmt (Elmt, E);
11980 Remove_Homonym (Subp);
11988 -- Step 2: Add primitives of progenitors that are not implemented by
11989 -- parents of Tagged_Type
11991 if Present (Interfaces (Base_Type (Tagged_Type))) then
11992 Iface_Elmt := First_Elmt (Interfaces (Base_Type (Tagged_Type)));
11993 while Present (Iface_Elmt) loop
11994 Iface := Node (Iface_Elmt);
11996 Prim_Elmt := First_Elmt (Primitive_Operations (Iface));
11997 while Present (Prim_Elmt) loop
11998 Iface_Subp := Node (Prim_Elmt);
12000 -- Exclude derivation of predefined primitives except those
12001 -- that come from source. Required to catch declarations of
12002 -- equality operators of interfaces. For example:
12004 -- type Iface is interface;
12005 -- function "=" (Left, Right : Iface) return Boolean;
12007 if not Is_Predefined_Dispatching_Operation (Iface_Subp)
12008 or else Comes_From_Source (Iface_Subp)
12010 E := Find_Primitive_Covering_Interface
12011 (Tagged_Type => Tagged_Type,
12012 Iface_Prim => Iface_Subp);
12014 -- If not found we derive a new primitive leaving its alias
12015 -- attribute referencing the interface primitive
12019 (New_Subp, Iface_Subp, Tagged_Type, Iface);
12021 -- Propagate to the full view interface entities associated
12022 -- with the partial view
12024 elsif In_Private_Part (Current_Scope)
12025 and then Present (Alias (E))
12026 and then Alias (E) = Iface_Subp
12028 List_Containing (Parent (E)) /=
12029 Private_Declarations
12031 (Unit_Declaration_Node (Current_Scope)))
12033 Append_Elmt (E, Primitive_Operations (Tagged_Type));
12037 Next_Elmt (Prim_Elmt);
12040 Next_Elmt (Iface_Elmt);
12043 end Derive_Progenitor_Subprograms;
12045 -----------------------
12046 -- Derive_Subprogram --
12047 -----------------------
12049 procedure Derive_Subprogram
12050 (New_Subp : in out Entity_Id;
12051 Parent_Subp : Entity_Id;
12052 Derived_Type : Entity_Id;
12053 Parent_Type : Entity_Id;
12054 Actual_Subp : Entity_Id := Empty)
12056 Formal : Entity_Id;
12057 -- Formal parameter of parent primitive operation
12059 Formal_Of_Actual : Entity_Id;
12060 -- Formal parameter of actual operation, when the derivation is to
12061 -- create a renaming for a primitive operation of an actual in an
12064 New_Formal : Entity_Id;
12065 -- Formal of inherited operation
12067 Visible_Subp : Entity_Id := Parent_Subp;
12069 function Is_Private_Overriding return Boolean;
12070 -- If Subp is a private overriding of a visible operation, the inherited
12071 -- operation derives from the overridden op (even though its body is the
12072 -- overriding one) and the inherited operation is visible now. See
12073 -- sem_disp to see the full details of the handling of the overridden
12074 -- subprogram, which is removed from the list of primitive operations of
12075 -- the type. The overridden subprogram is saved locally in Visible_Subp,
12076 -- and used to diagnose abstract operations that need overriding in the
12079 procedure Replace_Type (Id, New_Id : Entity_Id);
12080 -- When the type is an anonymous access type, create a new access type
12081 -- designating the derived type.
12083 procedure Set_Derived_Name;
12084 -- This procedure sets the appropriate Chars name for New_Subp. This
12085 -- is normally just a copy of the parent name. An exception arises for
12086 -- type support subprograms, where the name is changed to reflect the
12087 -- name of the derived type, e.g. if type foo is derived from type bar,
12088 -- then a procedure barDA is derived with a name fooDA.
12090 ---------------------------
12091 -- Is_Private_Overriding --
12092 ---------------------------
12094 function Is_Private_Overriding return Boolean is
12098 -- If the parent is not a dispatching operation there is no
12099 -- need to investigate overridings
12101 if not Is_Dispatching_Operation (Parent_Subp) then
12105 -- The visible operation that is overridden is a homonym of the
12106 -- parent subprogram. We scan the homonym chain to find the one
12107 -- whose alias is the subprogram we are deriving.
12109 Prev := Current_Entity (Parent_Subp);
12110 while Present (Prev) loop
12111 if Ekind (Prev) = Ekind (Parent_Subp)
12112 and then Alias (Prev) = Parent_Subp
12113 and then Scope (Parent_Subp) = Scope (Prev)
12114 and then not Is_Hidden (Prev)
12116 Visible_Subp := Prev;
12120 Prev := Homonym (Prev);
12124 end Is_Private_Overriding;
12130 procedure Replace_Type (Id, New_Id : Entity_Id) is
12131 Acc_Type : Entity_Id;
12132 Par : constant Node_Id := Parent (Derived_Type);
12135 -- When the type is an anonymous access type, create a new access
12136 -- type designating the derived type. This itype must be elaborated
12137 -- at the point of the derivation, not on subsequent calls that may
12138 -- be out of the proper scope for Gigi, so we insert a reference to
12139 -- it after the derivation.
12141 if Ekind (Etype (Id)) = E_Anonymous_Access_Type then
12143 Desig_Typ : Entity_Id := Designated_Type (Etype (Id));
12146 if Ekind (Desig_Typ) = E_Record_Type_With_Private
12147 and then Present (Full_View (Desig_Typ))
12148 and then not Is_Private_Type (Parent_Type)
12150 Desig_Typ := Full_View (Desig_Typ);
12153 if Base_Type (Desig_Typ) = Base_Type (Parent_Type)
12155 -- Ada 2005 (AI-251): Handle also derivations of abstract
12156 -- interface primitives.
12158 or else (Is_Interface (Desig_Typ)
12159 and then not Is_Class_Wide_Type (Desig_Typ))
12161 Acc_Type := New_Copy (Etype (Id));
12162 Set_Etype (Acc_Type, Acc_Type);
12163 Set_Scope (Acc_Type, New_Subp);
12165 -- Compute size of anonymous access type
12167 if Is_Array_Type (Desig_Typ)
12168 and then not Is_Constrained (Desig_Typ)
12170 Init_Size (Acc_Type, 2 * System_Address_Size);
12172 Init_Size (Acc_Type, System_Address_Size);
12175 Init_Alignment (Acc_Type);
12176 Set_Directly_Designated_Type (Acc_Type, Derived_Type);
12178 Set_Etype (New_Id, Acc_Type);
12179 Set_Scope (New_Id, New_Subp);
12181 -- Create a reference to it
12182 Build_Itype_Reference (Acc_Type, Parent (Derived_Type));
12185 Set_Etype (New_Id, Etype (Id));
12189 elsif Base_Type (Etype (Id)) = Base_Type (Parent_Type)
12191 (Ekind (Etype (Id)) = E_Record_Type_With_Private
12192 and then Present (Full_View (Etype (Id)))
12194 Base_Type (Full_View (Etype (Id))) = Base_Type (Parent_Type))
12196 -- Constraint checks on formals are generated during expansion,
12197 -- based on the signature of the original subprogram. The bounds
12198 -- of the derived type are not relevant, and thus we can use
12199 -- the base type for the formals. However, the return type may be
12200 -- used in a context that requires that the proper static bounds
12201 -- be used (a case statement, for example) and for those cases
12202 -- we must use the derived type (first subtype), not its base.
12204 -- If the derived_type_definition has no constraints, we know that
12205 -- the derived type has the same constraints as the first subtype
12206 -- of the parent, and we can also use it rather than its base,
12207 -- which can lead to more efficient code.
12209 if Etype (Id) = Parent_Type then
12210 if Is_Scalar_Type (Parent_Type)
12212 Subtypes_Statically_Compatible (Parent_Type, Derived_Type)
12214 Set_Etype (New_Id, Derived_Type);
12216 elsif Nkind (Par) = N_Full_Type_Declaration
12218 Nkind (Type_Definition (Par)) = N_Derived_Type_Definition
12221 (Subtype_Indication (Type_Definition (Par)))
12223 Set_Etype (New_Id, Derived_Type);
12226 Set_Etype (New_Id, Base_Type (Derived_Type));
12230 Set_Etype (New_Id, Base_Type (Derived_Type));
12233 -- Ada 2005 (AI-251): Handle derivations of abstract interface
12236 elsif Is_Interface (Etype (Id))
12237 and then not Is_Class_Wide_Type (Etype (Id))
12238 and then Is_Progenitor (Etype (Id), Derived_Type)
12240 Set_Etype (New_Id, Derived_Type);
12243 Set_Etype (New_Id, Etype (Id));
12247 ----------------------
12248 -- Set_Derived_Name --
12249 ----------------------
12251 procedure Set_Derived_Name is
12252 Nm : constant TSS_Name_Type := Get_TSS_Name (Parent_Subp);
12254 if Nm = TSS_Null then
12255 Set_Chars (New_Subp, Chars (Parent_Subp));
12257 Set_Chars (New_Subp, Make_TSS_Name (Base_Type (Derived_Type), Nm));
12259 end Set_Derived_Name;
12263 Parent_Overrides_Interface_Primitive : Boolean := False;
12265 -- Start of processing for Derive_Subprogram
12269 New_Entity (Nkind (Parent_Subp), Sloc (Derived_Type));
12270 Set_Ekind (New_Subp, Ekind (Parent_Subp));
12272 -- Check whether the parent overrides an interface primitive
12274 if Is_Overriding_Operation (Parent_Subp) then
12276 E : Entity_Id := Parent_Subp;
12278 while Present (Overridden_Operation (E)) loop
12279 E := Ultimate_Alias (Overridden_Operation (E));
12282 Parent_Overrides_Interface_Primitive :=
12283 Is_Dispatching_Operation (E)
12284 and then Present (Find_Dispatching_Type (E))
12285 and then Is_Interface (Find_Dispatching_Type (E));
12289 -- Check whether the inherited subprogram is a private operation that
12290 -- should be inherited but not yet made visible. Such subprograms can
12291 -- become visible at a later point (e.g., the private part of a public
12292 -- child unit) via Declare_Inherited_Private_Subprograms. If the
12293 -- following predicate is true, then this is not such a private
12294 -- operation and the subprogram simply inherits the name of the parent
12295 -- subprogram. Note the special check for the names of controlled
12296 -- operations, which are currently exempted from being inherited with
12297 -- a hidden name because they must be findable for generation of
12298 -- implicit run-time calls.
12300 if not Is_Hidden (Parent_Subp)
12301 or else Is_Internal (Parent_Subp)
12302 or else Is_Private_Overriding
12303 or else Is_Internal_Name (Chars (Parent_Subp))
12304 or else Chars (Parent_Subp) = Name_Initialize
12305 or else Chars (Parent_Subp) = Name_Adjust
12306 or else Chars (Parent_Subp) = Name_Finalize
12310 -- An inherited dispatching equality will be overridden by an internally
12311 -- generated one, or by an explicit one, so preserve its name and thus
12312 -- its entry in the dispatch table. Otherwise, if Parent_Subp is a
12313 -- private operation it may become invisible if the full view has
12314 -- progenitors, and the dispatch table will be malformed.
12315 -- We check that the type is limited to handle the anomalous declaration
12316 -- of Limited_Controlled, which is derived from a non-limited type, and
12317 -- which is handled specially elsewhere as well.
12319 elsif Chars (Parent_Subp) = Name_Op_Eq
12320 and then Is_Dispatching_Operation (Parent_Subp)
12321 and then Etype (Parent_Subp) = Standard_Boolean
12322 and then not Is_Limited_Type (Etype (First_Formal (Parent_Subp)))
12324 Etype (First_Formal (Parent_Subp)) =
12325 Etype (Next_Formal (First_Formal (Parent_Subp)))
12329 -- If parent is hidden, this can be a regular derivation if the
12330 -- parent is immediately visible in a non-instantiating context,
12331 -- or if we are in the private part of an instance. This test
12332 -- should still be refined ???
12334 -- The test for In_Instance_Not_Visible avoids inheriting the derived
12335 -- operation as a non-visible operation in cases where the parent
12336 -- subprogram might not be visible now, but was visible within the
12337 -- original generic, so it would be wrong to make the inherited
12338 -- subprogram non-visible now. (Not clear if this test is fully
12339 -- correct; are there any cases where we should declare the inherited
12340 -- operation as not visible to avoid it being overridden, e.g., when
12341 -- the parent type is a generic actual with private primitives ???)
12343 -- (they should be treated the same as other private inherited
12344 -- subprograms, but it's not clear how to do this cleanly). ???
12346 elsif (In_Open_Scopes (Scope (Base_Type (Parent_Type)))
12347 and then Is_Immediately_Visible (Parent_Subp)
12348 and then not In_Instance)
12349 or else In_Instance_Not_Visible
12353 -- Ada 2005 (AI-251): Regular derivation if the parent subprogram
12354 -- overrides an interface primitive because interface primitives
12355 -- must be visible in the partial view of the parent (RM 7.3 (7.3/2))
12357 elsif Parent_Overrides_Interface_Primitive then
12360 -- Otherwise, the type is inheriting a private operation, so enter
12361 -- it with a special name so it can't be overridden.
12364 Set_Chars (New_Subp, New_External_Name (Chars (Parent_Subp), 'P'));
12367 Set_Parent (New_Subp, Parent (Derived_Type));
12369 if Present (Actual_Subp) then
12370 Replace_Type (Actual_Subp, New_Subp);
12372 Replace_Type (Parent_Subp, New_Subp);
12375 Conditional_Delay (New_Subp, Parent_Subp);
12377 -- If we are creating a renaming for a primitive operation of an
12378 -- actual of a generic derived type, we must examine the signature
12379 -- of the actual primitive, not that of the generic formal, which for
12380 -- example may be an interface. However the name and initial value
12381 -- of the inherited operation are those of the formal primitive.
12383 Formal := First_Formal (Parent_Subp);
12385 if Present (Actual_Subp) then
12386 Formal_Of_Actual := First_Formal (Actual_Subp);
12388 Formal_Of_Actual := Empty;
12391 while Present (Formal) loop
12392 New_Formal := New_Copy (Formal);
12394 -- Normally we do not go copying parents, but in the case of
12395 -- formals, we need to link up to the declaration (which is the
12396 -- parameter specification), and it is fine to link up to the
12397 -- original formal's parameter specification in this case.
12399 Set_Parent (New_Formal, Parent (Formal));
12400 Append_Entity (New_Formal, New_Subp);
12402 if Present (Formal_Of_Actual) then
12403 Replace_Type (Formal_Of_Actual, New_Formal);
12404 Next_Formal (Formal_Of_Actual);
12406 Replace_Type (Formal, New_Formal);
12409 Next_Formal (Formal);
12412 -- If this derivation corresponds to a tagged generic actual, then
12413 -- primitive operations rename those of the actual. Otherwise the
12414 -- primitive operations rename those of the parent type, If the parent
12415 -- renames an intrinsic operator, so does the new subprogram. We except
12416 -- concatenation, which is always properly typed, and does not get
12417 -- expanded as other intrinsic operations.
12419 if No (Actual_Subp) then
12420 if Is_Intrinsic_Subprogram (Parent_Subp) then
12421 Set_Is_Intrinsic_Subprogram (New_Subp);
12423 if Present (Alias (Parent_Subp))
12424 and then Chars (Parent_Subp) /= Name_Op_Concat
12426 Set_Alias (New_Subp, Alias (Parent_Subp));
12428 Set_Alias (New_Subp, Parent_Subp);
12432 Set_Alias (New_Subp, Parent_Subp);
12436 Set_Alias (New_Subp, Actual_Subp);
12439 -- Derived subprograms of a tagged type must inherit the convention
12440 -- of the parent subprogram (a requirement of AI-117). Derived
12441 -- subprograms of untagged types simply get convention Ada by default.
12443 if Is_Tagged_Type (Derived_Type) then
12444 Set_Convention (New_Subp, Convention (Parent_Subp));
12447 -- Predefined controlled operations retain their name even if the parent
12448 -- is hidden (see above), but they are not primitive operations if the
12449 -- ancestor is not visible, for example if the parent is a private
12450 -- extension completed with a controlled extension. Note that a full
12451 -- type that is controlled can break privacy: the flag Is_Controlled is
12452 -- set on both views of the type.
12454 if Is_Controlled (Parent_Type)
12456 (Chars (Parent_Subp) = Name_Initialize
12457 or else Chars (Parent_Subp) = Name_Adjust
12458 or else Chars (Parent_Subp) = Name_Finalize)
12459 and then Is_Hidden (Parent_Subp)
12460 and then not Is_Visibly_Controlled (Parent_Type)
12462 Set_Is_Hidden (New_Subp);
12465 Set_Is_Imported (New_Subp, Is_Imported (Parent_Subp));
12466 Set_Is_Exported (New_Subp, Is_Exported (Parent_Subp));
12468 if Ekind (Parent_Subp) = E_Procedure then
12469 Set_Is_Valued_Procedure
12470 (New_Subp, Is_Valued_Procedure (Parent_Subp));
12473 -- No_Return must be inherited properly. If this is overridden in the
12474 -- case of a dispatching operation, then a check is made in Sem_Disp
12475 -- that the overriding operation is also No_Return (no such check is
12476 -- required for the case of non-dispatching operation.
12478 Set_No_Return (New_Subp, No_Return (Parent_Subp));
12480 -- A derived function with a controlling result is abstract. If the
12481 -- Derived_Type is a nonabstract formal generic derived type, then
12482 -- inherited operations are not abstract: the required check is done at
12483 -- instantiation time. If the derivation is for a generic actual, the
12484 -- function is not abstract unless the actual is.
12486 if Is_Generic_Type (Derived_Type)
12487 and then not Is_Abstract_Type (Derived_Type)
12491 -- Ada 2005 (AI-228): Calculate the "require overriding" and "abstract"
12492 -- properties of the subprogram, as defined in RM-3.9.3(4/2-6/2).
12494 elsif Ada_Version >= Ada_05
12495 and then (Is_Abstract_Subprogram (Alias (New_Subp))
12496 or else (Is_Tagged_Type (Derived_Type)
12497 and then Etype (New_Subp) = Derived_Type
12498 and then not Is_Null_Extension (Derived_Type))
12499 or else (Is_Tagged_Type (Derived_Type)
12500 and then Ekind (Etype (New_Subp)) =
12501 E_Anonymous_Access_Type
12502 and then Designated_Type (Etype (New_Subp)) =
12504 and then not Is_Null_Extension (Derived_Type)))
12505 and then No (Actual_Subp)
12507 if not Is_Tagged_Type (Derived_Type)
12508 or else Is_Abstract_Type (Derived_Type)
12509 or else Is_Abstract_Subprogram (Alias (New_Subp))
12511 Set_Is_Abstract_Subprogram (New_Subp);
12513 Set_Requires_Overriding (New_Subp);
12516 elsif Ada_Version < Ada_05
12517 and then (Is_Abstract_Subprogram (Alias (New_Subp))
12518 or else (Is_Tagged_Type (Derived_Type)
12519 and then Etype (New_Subp) = Derived_Type
12520 and then No (Actual_Subp)))
12522 Set_Is_Abstract_Subprogram (New_Subp);
12524 -- Finally, if the parent type is abstract we must verify that all
12525 -- inherited operations are either non-abstract or overridden, or that
12526 -- the derived type itself is abstract (this check is performed at the
12527 -- end of a package declaration, in Check_Abstract_Overriding). A
12528 -- private overriding in the parent type will not be visible in the
12529 -- derivation if we are not in an inner package or in a child unit of
12530 -- the parent type, in which case the abstractness of the inherited
12531 -- operation is carried to the new subprogram.
12533 elsif Is_Abstract_Type (Parent_Type)
12534 and then not In_Open_Scopes (Scope (Parent_Type))
12535 and then Is_Private_Overriding
12536 and then Is_Abstract_Subprogram (Visible_Subp)
12538 if No (Actual_Subp) then
12539 Set_Alias (New_Subp, Visible_Subp);
12540 Set_Is_Abstract_Subprogram (New_Subp, True);
12543 -- If this is a derivation for an instance of a formal derived
12544 -- type, abstractness comes from the primitive operation of the
12545 -- actual, not from the operation inherited from the ancestor.
12547 Set_Is_Abstract_Subprogram
12548 (New_Subp, Is_Abstract_Subprogram (Actual_Subp));
12552 New_Overloaded_Entity (New_Subp, Derived_Type);
12554 -- Check for case of a derived subprogram for the instantiation of a
12555 -- formal derived tagged type, if so mark the subprogram as dispatching
12556 -- and inherit the dispatching attributes of the parent subprogram. The
12557 -- derived subprogram is effectively renaming of the actual subprogram,
12558 -- so it needs to have the same attributes as the actual.
12560 if Present (Actual_Subp)
12561 and then Is_Dispatching_Operation (Parent_Subp)
12563 Set_Is_Dispatching_Operation (New_Subp);
12565 if Present (DTC_Entity (Parent_Subp)) then
12566 Set_DTC_Entity (New_Subp, DTC_Entity (Parent_Subp));
12567 Set_DT_Position (New_Subp, DT_Position (Parent_Subp));
12571 -- Indicate that a derived subprogram does not require a body and that
12572 -- it does not require processing of default expressions.
12574 Set_Has_Completion (New_Subp);
12575 Set_Default_Expressions_Processed (New_Subp);
12577 if Ekind (New_Subp) = E_Function then
12578 Set_Mechanism (New_Subp, Mechanism (Parent_Subp));
12580 end Derive_Subprogram;
12582 ------------------------
12583 -- Derive_Subprograms --
12584 ------------------------
12586 procedure Derive_Subprograms
12587 (Parent_Type : Entity_Id;
12588 Derived_Type : Entity_Id;
12589 Generic_Actual : Entity_Id := Empty)
12591 Op_List : constant Elist_Id :=
12592 Collect_Primitive_Operations (Parent_Type);
12594 function Check_Derived_Type return Boolean;
12595 -- Check that all primitive inherited from Parent_Type are found in
12596 -- the list of primitives of Derived_Type exactly in the same order.
12598 function Check_Derived_Type return Boolean is
12602 New_Subp : Entity_Id;
12607 -- Traverse list of entities in the current scope searching for
12608 -- an incomplete type whose full-view is derived type
12610 E := First_Entity (Scope (Derived_Type));
12612 and then E /= Derived_Type
12614 if Ekind (E) = E_Incomplete_Type
12615 and then Present (Full_View (E))
12616 and then Full_View (E) = Derived_Type
12618 -- Disable this test if Derived_Type completes an incomplete
12619 -- type because in such case more primitives can be added
12620 -- later to the list of primitives of Derived_Type by routine
12621 -- Process_Incomplete_Dependents
12626 E := Next_Entity (E);
12629 List := Collect_Primitive_Operations (Derived_Type);
12630 Elmt := First_Elmt (List);
12632 Op_Elmt := First_Elmt (Op_List);
12633 while Present (Op_Elmt) loop
12634 Subp := Node (Op_Elmt);
12635 New_Subp := Node (Elmt);
12637 -- At this early stage Derived_Type has no entities with attribute
12638 -- Interface_Alias. In addition, such primitives are always
12639 -- located at the end of the list of primitives of Parent_Type.
12640 -- Therefore, if found we can safely stop processing pending
12643 exit when Present (Interface_Alias (Subp));
12645 -- Handle hidden entities
12647 if not Is_Predefined_Dispatching_Operation (Subp)
12648 and then Is_Hidden (Subp)
12650 if Present (New_Subp)
12651 and then Primitive_Names_Match (Subp, New_Subp)
12657 if not Present (New_Subp)
12658 or else Ekind (Subp) /= Ekind (New_Subp)
12659 or else not Primitive_Names_Match (Subp, New_Subp)
12667 Next_Elmt (Op_Elmt);
12671 end Check_Derived_Type;
12675 Alias_Subp : Entity_Id;
12676 Act_List : Elist_Id;
12677 Act_Elmt : Elmt_Id := No_Elmt;
12678 Act_Subp : Entity_Id := Empty;
12680 Need_Search : Boolean := False;
12681 New_Subp : Entity_Id := Empty;
12682 Parent_Base : Entity_Id;
12685 -- Start of processing for Derive_Subprograms
12688 if Ekind (Parent_Type) = E_Record_Type_With_Private
12689 and then Has_Discriminants (Parent_Type)
12690 and then Present (Full_View (Parent_Type))
12692 Parent_Base := Full_View (Parent_Type);
12694 Parent_Base := Parent_Type;
12697 if Present (Generic_Actual) then
12698 Act_List := Collect_Primitive_Operations (Generic_Actual);
12699 Act_Elmt := First_Elmt (Act_List);
12702 -- Derive primitives inherited from the parent. Note that if the generic
12703 -- actual is present, this is not really a type derivation, it is a
12704 -- completion within an instance.
12706 -- Case 1: Derived_Type does not implement interfaces
12708 if not Is_Tagged_Type (Derived_Type)
12709 or else (not Has_Interfaces (Derived_Type)
12710 and then not (Present (Generic_Actual)
12712 Has_Interfaces (Generic_Actual)))
12714 Elmt := First_Elmt (Op_List);
12715 while Present (Elmt) loop
12716 Subp := Node (Elmt);
12718 -- Literals are derived earlier in the process of building the
12719 -- derived type, and are skipped here.
12721 if Ekind (Subp) = E_Enumeration_Literal then
12724 -- The actual is a direct descendant and the common primitive
12725 -- operations appear in the same order.
12727 -- If the generic parent type is present, the derived type is an
12728 -- instance of a formal derived type, and within the instance its
12729 -- operations are those of the actual. We derive from the formal
12730 -- type but make the inherited operations aliases of the
12731 -- corresponding operations of the actual.
12735 (New_Subp, Subp, Derived_Type, Parent_Base, Node (Act_Elmt));
12737 if Present (Act_Elmt) then
12738 Next_Elmt (Act_Elmt);
12745 -- Case 2: Derived_Type implements interfaces
12748 -- If the parent type has no predefined primitives we remove
12749 -- predefined primitives from the list of primitives of generic
12750 -- actual to simplify the complexity of this algorithm.
12752 if Present (Generic_Actual) then
12754 Has_Predefined_Primitives : Boolean := False;
12757 -- Check if the parent type has predefined primitives
12759 Elmt := First_Elmt (Op_List);
12760 while Present (Elmt) loop
12761 Subp := Node (Elmt);
12763 if Is_Predefined_Dispatching_Operation (Subp)
12764 and then not Comes_From_Source (Ultimate_Alias (Subp))
12766 Has_Predefined_Primitives := True;
12773 -- Remove predefined primitives of Generic_Actual. We must use
12774 -- an auxiliary list because in case of tagged types the value
12775 -- returned by Collect_Primitive_Operations is the value stored
12776 -- in its Primitive_Operations attribute (and we don't want to
12777 -- modify its current contents).
12779 if not Has_Predefined_Primitives then
12781 Aux_List : constant Elist_Id := New_Elmt_List;
12784 Elmt := First_Elmt (Act_List);
12785 while Present (Elmt) loop
12786 Subp := Node (Elmt);
12788 if not Is_Predefined_Dispatching_Operation (Subp)
12789 or else Comes_From_Source (Subp)
12791 Append_Elmt (Subp, Aux_List);
12797 Act_List := Aux_List;
12801 Act_Elmt := First_Elmt (Act_List);
12802 Act_Subp := Node (Act_Elmt);
12806 -- Stage 1: If the generic actual is not present we derive the
12807 -- primitives inherited from the parent type. If the generic parent
12808 -- type is present, the derived type is an instance of a formal
12809 -- derived type, and within the instance its operations are those of
12810 -- the actual. We derive from the formal type but make the inherited
12811 -- operations aliases of the corresponding operations of the actual.
12813 Elmt := First_Elmt (Op_List);
12814 while Present (Elmt) loop
12815 Subp := Node (Elmt);
12816 Alias_Subp := Ultimate_Alias (Subp);
12818 -- At this early stage Derived_Type has no entities with attribute
12819 -- Interface_Alias. In addition, such primitives are always
12820 -- located at the end of the list of primitives of Parent_Type.
12821 -- Therefore, if found we can safely stop processing pending
12824 exit when Present (Interface_Alias (Subp));
12826 -- If the generic actual is present find the corresponding
12827 -- operation in the generic actual. If the parent type is a
12828 -- direct ancestor of the derived type then, even if it is an
12829 -- interface, the operations are inherited from the primary
12830 -- dispatch table and are in the proper order. If we detect here
12831 -- that primitives are not in the same order we traverse the list
12832 -- of primitive operations of the actual to find the one that
12833 -- implements the interface primitive.
12837 (Present (Generic_Actual)
12838 and then Present (Act_Subp)
12839 and then not Primitive_Names_Match (Subp, Act_Subp))
12841 pragma Assert (not Is_Ancestor (Parent_Base, Generic_Actual));
12843 -- Remember that we need searching for all pending primitives
12845 Need_Search := True;
12847 -- Handle entities associated with interface primitives
12849 if Present (Alias (Subp))
12850 and then Is_Interface (Find_Dispatching_Type (Alias (Subp)))
12851 and then not Is_Predefined_Dispatching_Operation (Subp)
12854 Find_Primitive_Covering_Interface
12855 (Tagged_Type => Generic_Actual,
12856 Iface_Prim => Subp);
12858 -- Handle predefined primitives plus the rest of user-defined
12862 Act_Elmt := First_Elmt (Act_List);
12863 while Present (Act_Elmt) loop
12864 Act_Subp := Node (Act_Elmt);
12866 exit when Primitive_Names_Match (Subp, Act_Subp)
12867 and then Type_Conformant
12869 Skip_Controlling_Formals => True)
12870 and then No (Interface_Alias (Act_Subp));
12872 Next_Elmt (Act_Elmt);
12877 -- Case 1: If the parent is a limited interface then it has the
12878 -- predefined primitives of synchronized interfaces. However, the
12879 -- actual type may be a non-limited type and hence it does not
12880 -- have such primitives.
12882 if Present (Generic_Actual)
12883 and then not Present (Act_Subp)
12884 and then Is_Limited_Interface (Parent_Base)
12885 and then Is_Predefined_Interface_Primitive (Subp)
12889 -- Case 2: Inherit entities associated with interfaces that
12890 -- were not covered by the parent type. We exclude here null
12891 -- interface primitives because they do not need special
12894 elsif Present (Alias (Subp))
12895 and then Is_Interface (Find_Dispatching_Type (Alias_Subp))
12897 (Nkind (Parent (Alias_Subp)) = N_Procedure_Specification
12898 and then Null_Present (Parent (Alias_Subp)))
12901 (New_Subp => New_Subp,
12902 Parent_Subp => Alias_Subp,
12903 Derived_Type => Derived_Type,
12904 Parent_Type => Find_Dispatching_Type (Alias_Subp),
12905 Actual_Subp => Act_Subp);
12907 if No (Generic_Actual) then
12908 Set_Alias (New_Subp, Subp);
12911 -- Case 3: Common derivation
12915 (New_Subp => New_Subp,
12916 Parent_Subp => Subp,
12917 Derived_Type => Derived_Type,
12918 Parent_Type => Parent_Base,
12919 Actual_Subp => Act_Subp);
12922 -- No need to update Act_Elm if we must search for the
12923 -- corresponding operation in the generic actual
12926 and then Present (Act_Elmt)
12928 Next_Elmt (Act_Elmt);
12929 Act_Subp := Node (Act_Elmt);
12935 -- Inherit additional operations from progenitors. If the derived
12936 -- type is a generic actual, there are not new primitive operations
12937 -- for the type because it has those of the actual, and therefore
12938 -- nothing needs to be done. The renamings generated above are not
12939 -- primitive operations, and their purpose is simply to make the
12940 -- proper operations visible within an instantiation.
12942 if No (Generic_Actual) then
12943 Derive_Progenitor_Subprograms (Parent_Base, Derived_Type);
12947 -- Final check: Direct descendants must have their primitives in the
12948 -- same order. We exclude from this test non-tagged types and instances
12949 -- of formal derived types. We skip this test if we have already
12950 -- reported serious errors in the sources.
12952 pragma Assert (not Is_Tagged_Type (Derived_Type)
12953 or else Present (Generic_Actual)
12954 or else Serious_Errors_Detected > 0
12955 or else Check_Derived_Type);
12956 end Derive_Subprograms;
12958 --------------------------------
12959 -- Derived_Standard_Character --
12960 --------------------------------
12962 procedure Derived_Standard_Character
12964 Parent_Type : Entity_Id;
12965 Derived_Type : Entity_Id)
12967 Loc : constant Source_Ptr := Sloc (N);
12968 Def : constant Node_Id := Type_Definition (N);
12969 Indic : constant Node_Id := Subtype_Indication (Def);
12970 Parent_Base : constant Entity_Id := Base_Type (Parent_Type);
12971 Implicit_Base : constant Entity_Id :=
12973 (E_Enumeration_Type, N, Derived_Type, 'B');
12979 Discard_Node (Process_Subtype (Indic, N));
12981 Set_Etype (Implicit_Base, Parent_Base);
12982 Set_Size_Info (Implicit_Base, Root_Type (Parent_Type));
12983 Set_RM_Size (Implicit_Base, RM_Size (Root_Type (Parent_Type)));
12985 Set_Is_Character_Type (Implicit_Base, True);
12986 Set_Has_Delayed_Freeze (Implicit_Base);
12988 -- The bounds of the implicit base are the bounds of the parent base.
12989 -- Note that their type is the parent base.
12991 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Base));
12992 Hi := New_Copy_Tree (Type_High_Bound (Parent_Base));
12994 Set_Scalar_Range (Implicit_Base,
12997 High_Bound => Hi));
12999 Conditional_Delay (Derived_Type, Parent_Type);
13001 Set_Ekind (Derived_Type, E_Enumeration_Subtype);
13002 Set_Etype (Derived_Type, Implicit_Base);
13003 Set_Size_Info (Derived_Type, Parent_Type);
13005 if Unknown_RM_Size (Derived_Type) then
13006 Set_RM_Size (Derived_Type, RM_Size (Parent_Type));
13009 Set_Is_Character_Type (Derived_Type, True);
13011 if Nkind (Indic) /= N_Subtype_Indication then
13013 -- If no explicit constraint, the bounds are those
13014 -- of the parent type.
13016 Lo := New_Copy_Tree (Type_Low_Bound (Parent_Type));
13017 Hi := New_Copy_Tree (Type_High_Bound (Parent_Type));
13018 Set_Scalar_Range (Derived_Type, Make_Range (Loc, Lo, Hi));
13021 Convert_Scalar_Bounds (N, Parent_Type, Derived_Type, Loc);
13023 -- Because the implicit base is used in the conversion of the bounds, we
13024 -- have to freeze it now. This is similar to what is done for numeric
13025 -- types, and it equally suspicious, but otherwise a non-static bound
13026 -- will have a reference to an unfrozen type, which is rejected by Gigi
13027 -- (???). This requires specific care for definition of stream
13028 -- attributes. For details, see comments at the end of
13029 -- Build_Derived_Numeric_Type.
13031 Freeze_Before (N, Implicit_Base);
13032 end Derived_Standard_Character;
13034 ------------------------------
13035 -- Derived_Type_Declaration --
13036 ------------------------------
13038 procedure Derived_Type_Declaration
13041 Is_Completion : Boolean)
13043 Parent_Type : Entity_Id;
13045 function Comes_From_Generic (Typ : Entity_Id) return Boolean;
13046 -- Check whether the parent type is a generic formal, or derives
13047 -- directly or indirectly from one.
13049 ------------------------
13050 -- Comes_From_Generic --
13051 ------------------------
13053 function Comes_From_Generic (Typ : Entity_Id) return Boolean is
13055 if Is_Generic_Type (Typ) then
13058 elsif Is_Generic_Type (Root_Type (Parent_Type)) then
13061 elsif Is_Private_Type (Typ)
13062 and then Present (Full_View (Typ))
13063 and then Is_Generic_Type (Root_Type (Full_View (Typ)))
13067 elsif Is_Generic_Actual_Type (Typ) then
13073 end Comes_From_Generic;
13077 Def : constant Node_Id := Type_Definition (N);
13078 Iface_Def : Node_Id;
13079 Indic : constant Node_Id := Subtype_Indication (Def);
13080 Extension : constant Node_Id := Record_Extension_Part (Def);
13081 Parent_Node : Node_Id;
13082 Parent_Scope : Entity_Id;
13085 -- Start of processing for Derived_Type_Declaration
13088 Parent_Type := Find_Type_Of_Subtype_Indic (Indic);
13090 -- Ada 2005 (AI-251): In case of interface derivation check that the
13091 -- parent is also an interface.
13093 if Interface_Present (Def) then
13094 if not Is_Interface (Parent_Type) then
13095 Diagnose_Interface (Indic, Parent_Type);
13098 Parent_Node := Parent (Base_Type (Parent_Type));
13099 Iface_Def := Type_Definition (Parent_Node);
13101 -- Ada 2005 (AI-251): Limited interfaces can only inherit from
13102 -- other limited interfaces.
13104 if Limited_Present (Def) then
13105 if Limited_Present (Iface_Def) then
13108 elsif Protected_Present (Iface_Def) then
13110 ("descendant of& must be declared"
13111 & " as a protected interface",
13114 elsif Synchronized_Present (Iface_Def) then
13116 ("descendant of& must be declared"
13117 & " as a synchronized interface",
13120 elsif Task_Present (Iface_Def) then
13122 ("descendant of& must be declared as a task interface",
13127 ("(Ada 2005) limited interface cannot "
13128 & "inherit from non-limited interface", Indic);
13131 -- Ada 2005 (AI-345): Non-limited interfaces can only inherit
13132 -- from non-limited or limited interfaces.
13134 elsif not Protected_Present (Def)
13135 and then not Synchronized_Present (Def)
13136 and then not Task_Present (Def)
13138 if Limited_Present (Iface_Def) then
13141 elsif Protected_Present (Iface_Def) then
13143 ("descendant of& must be declared"
13144 & " as a protected interface",
13147 elsif Synchronized_Present (Iface_Def) then
13149 ("descendant of& must be declared"
13150 & " as a synchronized interface",
13153 elsif Task_Present (Iface_Def) then
13155 ("descendant of& must be declared as a task interface",
13164 if Is_Tagged_Type (Parent_Type)
13165 and then Is_Concurrent_Type (Parent_Type)
13166 and then not Is_Interface (Parent_Type)
13169 ("parent type of a record extension cannot be "
13170 & "a synchronized tagged type (RM 3.9.1 (3/1))", N);
13171 Set_Etype (T, Any_Type);
13175 -- Ada 2005 (AI-251): Decorate all the names in the list of ancestor
13178 if Is_Tagged_Type (Parent_Type)
13179 and then Is_Non_Empty_List (Interface_List (Def))
13186 Intf := First (Interface_List (Def));
13187 while Present (Intf) loop
13188 T := Find_Type_Of_Subtype_Indic (Intf);
13190 if not Is_Interface (T) then
13191 Diagnose_Interface (Intf, T);
13193 -- Check the rules of 3.9.4(12/2) and 7.5(2/2) that disallow
13194 -- a limited type from having a nonlimited progenitor.
13196 elsif (Limited_Present (Def)
13197 or else (not Is_Interface (Parent_Type)
13198 and then Is_Limited_Type (Parent_Type)))
13199 and then not Is_Limited_Interface (T)
13202 ("progenitor interface& of limited type must be limited",
13211 if Parent_Type = Any_Type
13212 or else Etype (Parent_Type) = Any_Type
13213 or else (Is_Class_Wide_Type (Parent_Type)
13214 and then Etype (Parent_Type) = T)
13216 -- If Parent_Type is undefined or illegal, make new type into a
13217 -- subtype of Any_Type, and set a few attributes to prevent cascaded
13218 -- errors. If this is a self-definition, emit error now.
13221 or else T = Etype (Parent_Type)
13223 Error_Msg_N ("type cannot be used in its own definition", Indic);
13226 Set_Ekind (T, Ekind (Parent_Type));
13227 Set_Etype (T, Any_Type);
13228 Set_Scalar_Range (T, Scalar_Range (Any_Type));
13230 if Is_Tagged_Type (T) then
13231 Set_Primitive_Operations (T, New_Elmt_List);
13237 -- Ada 2005 (AI-251): The case in which the parent of the full-view is
13238 -- an interface is special because the list of interfaces in the full
13239 -- view can be given in any order. For example:
13241 -- type A is interface;
13242 -- type B is interface and A;
13243 -- type D is new B with private;
13245 -- type D is new A and B with null record; -- 1 --
13247 -- In this case we perform the following transformation of -1-:
13249 -- type D is new B and A with null record;
13251 -- If the parent of the full-view covers the parent of the partial-view
13252 -- we have two possible cases:
13254 -- 1) They have the same parent
13255 -- 2) The parent of the full-view implements some further interfaces
13257 -- In both cases we do not need to perform the transformation. In the
13258 -- first case the source program is correct and the transformation is
13259 -- not needed; in the second case the source program does not fulfill
13260 -- the no-hidden interfaces rule (AI-396) and the error will be reported
13263 -- This transformation not only simplifies the rest of the analysis of
13264 -- this type declaration but also simplifies the correct generation of
13265 -- the object layout to the expander.
13267 if In_Private_Part (Current_Scope)
13268 and then Is_Interface (Parent_Type)
13272 Partial_View : Entity_Id;
13273 Partial_View_Parent : Entity_Id;
13274 New_Iface : Node_Id;
13277 -- Look for the associated private type declaration
13279 Partial_View := First_Entity (Current_Scope);
13281 exit when No (Partial_View)
13282 or else (Has_Private_Declaration (Partial_View)
13283 and then Full_View (Partial_View) = T);
13285 Next_Entity (Partial_View);
13288 -- If the partial view was not found then the source code has
13289 -- errors and the transformation is not needed.
13291 if Present (Partial_View) then
13292 Partial_View_Parent := Etype (Partial_View);
13294 -- If the parent of the full-view covers the parent of the
13295 -- partial-view we have nothing else to do.
13297 if Interface_Present_In_Ancestor
13298 (Parent_Type, Partial_View_Parent)
13302 -- Traverse the list of interfaces of the full-view to look
13303 -- for the parent of the partial-view and perform the tree
13307 Iface := First (Interface_List (Def));
13308 while Present (Iface) loop
13309 if Etype (Iface) = Etype (Partial_View) then
13310 Rewrite (Subtype_Indication (Def),
13311 New_Copy (Subtype_Indication
13312 (Parent (Partial_View))));
13314 New_Iface := Make_Identifier (Sloc (N),
13315 Chars (Parent_Type));
13316 Append (New_Iface, Interface_List (Def));
13318 -- Analyze the transformed code
13320 Derived_Type_Declaration (T, N, Is_Completion);
13331 -- Only composite types other than array types are allowed to have
13334 if Present (Discriminant_Specifications (N))
13335 and then (Is_Elementary_Type (Parent_Type)
13336 or else Is_Array_Type (Parent_Type))
13337 and then not Error_Posted (N)
13340 ("elementary or array type cannot have discriminants",
13341 Defining_Identifier (First (Discriminant_Specifications (N))));
13342 Set_Has_Discriminants (T, False);
13345 -- In Ada 83, a derived type defined in a package specification cannot
13346 -- be used for further derivation until the end of its visible part.
13347 -- Note that derivation in the private part of the package is allowed.
13349 if Ada_Version = Ada_83
13350 and then Is_Derived_Type (Parent_Type)
13351 and then In_Visible_Part (Scope (Parent_Type))
13353 if Ada_Version = Ada_83 and then Comes_From_Source (Indic) then
13355 ("(Ada 83): premature use of type for derivation", Indic);
13359 -- Check for early use of incomplete or private type
13361 if Ekind_In (Parent_Type, E_Void, E_Incomplete_Type) then
13362 Error_Msg_N ("premature derivation of incomplete type", Indic);
13365 elsif (Is_Incomplete_Or_Private_Type (Parent_Type)
13366 and then not Comes_From_Generic (Parent_Type))
13367 or else Has_Private_Component (Parent_Type)
13369 -- The ancestor type of a formal type can be incomplete, in which
13370 -- case only the operations of the partial view are available in
13371 -- the generic. Subsequent checks may be required when the full
13372 -- view is analyzed, to verify that derivation from a tagged type
13373 -- has an extension.
13375 if Nkind (Original_Node (N)) = N_Formal_Type_Declaration then
13378 elsif No (Underlying_Type (Parent_Type))
13379 or else Has_Private_Component (Parent_Type)
13382 ("premature derivation of derived or private type", Indic);
13384 -- Flag the type itself as being in error, this prevents some
13385 -- nasty problems with subsequent uses of the malformed type.
13387 Set_Error_Posted (T);
13389 -- Check that within the immediate scope of an untagged partial
13390 -- view it's illegal to derive from the partial view if the
13391 -- full view is tagged. (7.3(7))
13393 -- We verify that the Parent_Type is a partial view by checking
13394 -- that it is not a Full_Type_Declaration (i.e. a private type or
13395 -- private extension declaration), to distinguish a partial view
13396 -- from a derivation from a private type which also appears as
13399 elsif Present (Full_View (Parent_Type))
13400 and then Nkind (Parent (Parent_Type)) /= N_Full_Type_Declaration
13401 and then not Is_Tagged_Type (Parent_Type)
13402 and then Is_Tagged_Type (Full_View (Parent_Type))
13404 Parent_Scope := Scope (T);
13405 while Present (Parent_Scope)
13406 and then Parent_Scope /= Standard_Standard
13408 if Parent_Scope = Scope (Parent_Type) then
13410 ("premature derivation from type with tagged full view",
13414 Parent_Scope := Scope (Parent_Scope);
13419 -- Check that form of derivation is appropriate
13421 Taggd := Is_Tagged_Type (Parent_Type);
13423 -- Perhaps the parent type should be changed to the class-wide type's
13424 -- specific type in this case to prevent cascading errors ???
13426 if Present (Extension) and then Is_Class_Wide_Type (Parent_Type) then
13427 Error_Msg_N ("parent type must not be a class-wide type", Indic);
13431 if Present (Extension) and then not Taggd then
13433 ("type derived from untagged type cannot have extension", Indic);
13435 elsif No (Extension) and then Taggd then
13437 -- If this declaration is within a private part (or body) of a
13438 -- generic instantiation then the derivation is allowed (the parent
13439 -- type can only appear tagged in this case if it's a generic actual
13440 -- type, since it would otherwise have been rejected in the analysis
13441 -- of the generic template).
13443 if not Is_Generic_Actual_Type (Parent_Type)
13444 or else In_Visible_Part (Scope (Parent_Type))
13447 ("type derived from tagged type must have extension", Indic);
13451 -- AI-443: Synchronized formal derived types require a private
13452 -- extension. There is no point in checking the ancestor type or
13453 -- the progenitors since the construct is wrong to begin with.
13455 if Ada_Version >= Ada_05
13456 and then Is_Generic_Type (T)
13457 and then Present (Original_Node (N))
13460 Decl : constant Node_Id := Original_Node (N);
13463 if Nkind (Decl) = N_Formal_Type_Declaration
13464 and then Nkind (Formal_Type_Definition (Decl)) =
13465 N_Formal_Derived_Type_Definition
13466 and then Synchronized_Present (Formal_Type_Definition (Decl))
13467 and then No (Extension)
13469 -- Avoid emitting a duplicate error message
13471 and then not Error_Posted (Indic)
13474 ("synchronized derived type must have extension", N);
13479 if Null_Exclusion_Present (Def)
13480 and then not Is_Access_Type (Parent_Type)
13482 Error_Msg_N ("null exclusion can only apply to an access type", N);
13485 -- Avoid deriving parent primitives of underlying record views
13487 Build_Derived_Type (N, Parent_Type, T, Is_Completion,
13488 Derive_Subps => not Is_Underlying_Record_View (T));
13490 -- AI-419: The parent type of an explicitly limited derived type must
13491 -- be a limited type or a limited interface.
13493 if Limited_Present (Def) then
13494 Set_Is_Limited_Record (T);
13496 if Is_Interface (T) then
13497 Set_Is_Limited_Interface (T);
13500 if not Is_Limited_Type (Parent_Type)
13502 (not Is_Interface (Parent_Type)
13503 or else not Is_Limited_Interface (Parent_Type))
13505 Error_Msg_NE ("parent type& of limited type must be limited",
13509 end Derived_Type_Declaration;
13511 ------------------------
13512 -- Diagnose_Interface --
13513 ------------------------
13515 procedure Diagnose_Interface (N : Node_Id; E : Entity_Id) is
13517 if not Is_Interface (E)
13518 and then E /= Any_Type
13520 Error_Msg_NE ("(Ada 2005) & must be an interface", N, E);
13522 end Diagnose_Interface;
13524 ----------------------------------
13525 -- Enumeration_Type_Declaration --
13526 ----------------------------------
13528 procedure Enumeration_Type_Declaration (T : Entity_Id; Def : Node_Id) is
13535 -- Create identifier node representing lower bound
13537 B_Node := New_Node (N_Identifier, Sloc (Def));
13538 L := First (Literals (Def));
13539 Set_Chars (B_Node, Chars (L));
13540 Set_Entity (B_Node, L);
13541 Set_Etype (B_Node, T);
13542 Set_Is_Static_Expression (B_Node, True);
13544 R_Node := New_Node (N_Range, Sloc (Def));
13545 Set_Low_Bound (R_Node, B_Node);
13547 Set_Ekind (T, E_Enumeration_Type);
13548 Set_First_Literal (T, L);
13550 Set_Is_Constrained (T);
13554 -- Loop through literals of enumeration type setting pos and rep values
13555 -- except that if the Ekind is already set, then it means the literal
13556 -- was already constructed (case of a derived type declaration and we
13557 -- should not disturb the Pos and Rep values.
13559 while Present (L) loop
13560 if Ekind (L) /= E_Enumeration_Literal then
13561 Set_Ekind (L, E_Enumeration_Literal);
13562 Set_Enumeration_Pos (L, Ev);
13563 Set_Enumeration_Rep (L, Ev);
13564 Set_Is_Known_Valid (L, True);
13568 New_Overloaded_Entity (L);
13569 Generate_Definition (L);
13570 Set_Convention (L, Convention_Intrinsic);
13572 if Nkind (L) = N_Defining_Character_Literal then
13573 Set_Is_Character_Type (T, True);
13580 -- Now create a node representing upper bound
13582 B_Node := New_Node (N_Identifier, Sloc (Def));
13583 Set_Chars (B_Node, Chars (Last (Literals (Def))));
13584 Set_Entity (B_Node, Last (Literals (Def)));
13585 Set_Etype (B_Node, T);
13586 Set_Is_Static_Expression (B_Node, True);
13588 Set_High_Bound (R_Node, B_Node);
13590 -- Initialize various fields of the type. Some of this information
13591 -- may be overwritten later through rep.clauses.
13593 Set_Scalar_Range (T, R_Node);
13594 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
13595 Set_Enum_Esize (T);
13596 Set_Enum_Pos_To_Rep (T, Empty);
13598 -- Set Discard_Names if configuration pragma set, or if there is
13599 -- a parameterless pragma in the current declarative region
13601 if Global_Discard_Names
13602 or else Discard_Names (Scope (T))
13604 Set_Discard_Names (T);
13607 -- Process end label if there is one
13609 if Present (Def) then
13610 Process_End_Label (Def, 'e', T);
13612 end Enumeration_Type_Declaration;
13614 ---------------------------------
13615 -- Expand_To_Stored_Constraint --
13616 ---------------------------------
13618 function Expand_To_Stored_Constraint
13620 Constraint : Elist_Id) return Elist_Id
13622 Explicitly_Discriminated_Type : Entity_Id;
13623 Expansion : Elist_Id;
13624 Discriminant : Entity_Id;
13626 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id;
13627 -- Find the nearest type that actually specifies discriminants
13629 ---------------------------------
13630 -- Type_With_Explicit_Discrims --
13631 ---------------------------------
13633 function Type_With_Explicit_Discrims (Id : Entity_Id) return Entity_Id is
13634 Typ : constant E := Base_Type (Id);
13637 if Ekind (Typ) in Incomplete_Or_Private_Kind then
13638 if Present (Full_View (Typ)) then
13639 return Type_With_Explicit_Discrims (Full_View (Typ));
13643 if Has_Discriminants (Typ) then
13648 if Etype (Typ) = Typ then
13650 elsif Has_Discriminants (Typ) then
13653 return Type_With_Explicit_Discrims (Etype (Typ));
13656 end Type_With_Explicit_Discrims;
13658 -- Start of processing for Expand_To_Stored_Constraint
13662 or else Is_Empty_Elmt_List (Constraint)
13667 Explicitly_Discriminated_Type := Type_With_Explicit_Discrims (Typ);
13669 if No (Explicitly_Discriminated_Type) then
13673 Expansion := New_Elmt_List;
13676 First_Stored_Discriminant (Explicitly_Discriminated_Type);
13677 while Present (Discriminant) loop
13679 Get_Discriminant_Value (
13680 Discriminant, Explicitly_Discriminated_Type, Constraint),
13682 Next_Stored_Discriminant (Discriminant);
13686 end Expand_To_Stored_Constraint;
13688 ---------------------------
13689 -- Find_Hidden_Interface --
13690 ---------------------------
13692 function Find_Hidden_Interface
13694 Dest : Elist_Id) return Entity_Id
13697 Iface_Elmt : Elmt_Id;
13700 if Present (Src) and then Present (Dest) then
13701 Iface_Elmt := First_Elmt (Src);
13702 while Present (Iface_Elmt) loop
13703 Iface := Node (Iface_Elmt);
13705 if Is_Interface (Iface)
13706 and then not Contain_Interface (Iface, Dest)
13711 Next_Elmt (Iface_Elmt);
13716 end Find_Hidden_Interface;
13718 --------------------
13719 -- Find_Type_Name --
13720 --------------------
13722 function Find_Type_Name (N : Node_Id) return Entity_Id is
13723 Id : constant Entity_Id := Defining_Identifier (N);
13725 New_Id : Entity_Id;
13726 Prev_Par : Node_Id;
13728 procedure Tag_Mismatch;
13729 -- Diagnose a tagged partial view whose full view is untagged.
13730 -- We post the message on the full view, with a reference to
13731 -- the previous partial view. The partial view can be private
13732 -- or incomplete, and these are handled in a different manner,
13733 -- so we determine the position of the error message from the
13734 -- respective slocs of both.
13740 procedure Tag_Mismatch is
13742 if Sloc (Prev) < Sloc (Id) then
13744 ("full declaration of } must be a tagged type ", Id, Prev);
13747 ("full declaration of } must be a tagged type ", Prev, Id);
13751 -- Start of processing for Find_Type_Name
13754 -- Find incomplete declaration, if one was given
13756 Prev := Current_Entity_In_Scope (Id);
13758 if Present (Prev) then
13760 -- Previous declaration exists. Error if not incomplete/private case
13761 -- except if previous declaration is implicit, etc. Enter_Name will
13762 -- emit error if appropriate.
13764 Prev_Par := Parent (Prev);
13766 if not Is_Incomplete_Or_Private_Type (Prev) then
13770 elsif not Nkind_In (N, N_Full_Type_Declaration,
13771 N_Task_Type_Declaration,
13772 N_Protected_Type_Declaration)
13774 -- Completion must be a full type declarations (RM 7.3(4))
13776 Error_Msg_Sloc := Sloc (Prev);
13777 Error_Msg_NE ("invalid completion of }", Id, Prev);
13779 -- Set scope of Id to avoid cascaded errors. Entity is never
13780 -- examined again, except when saving globals in generics.
13782 Set_Scope (Id, Current_Scope);
13785 -- If this is a repeated incomplete declaration, no further
13786 -- checks are possible.
13788 if Nkind (N) = N_Incomplete_Type_Declaration then
13792 -- Case of full declaration of incomplete type
13794 elsif Ekind (Prev) = E_Incomplete_Type then
13796 -- Indicate that the incomplete declaration has a matching full
13797 -- declaration. The defining occurrence of the incomplete
13798 -- declaration remains the visible one, and the procedure
13799 -- Get_Full_View dereferences it whenever the type is used.
13801 if Present (Full_View (Prev)) then
13802 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
13805 Set_Full_View (Prev, Id);
13806 Append_Entity (Id, Current_Scope);
13807 Set_Is_Public (Id, Is_Public (Prev));
13808 Set_Is_Internal (Id);
13811 -- Case of full declaration of private type
13814 if Nkind (Parent (Prev)) /= N_Private_Extension_Declaration then
13815 if Etype (Prev) /= Prev then
13817 -- Prev is a private subtype or a derived type, and needs
13820 Error_Msg_NE ("invalid redeclaration of }", Id, Prev);
13823 elsif Ekind (Prev) = E_Private_Type
13824 and then Nkind_In (N, N_Task_Type_Declaration,
13825 N_Protected_Type_Declaration)
13828 ("completion of nonlimited type cannot be limited", N);
13830 elsif Ekind (Prev) = E_Record_Type_With_Private
13831 and then Nkind_In (N, N_Task_Type_Declaration,
13832 N_Protected_Type_Declaration)
13834 if not Is_Limited_Record (Prev) then
13836 ("completion of nonlimited type cannot be limited", N);
13838 elsif No (Interface_List (N)) then
13840 ("completion of tagged private type must be tagged",
13844 elsif Nkind (N) = N_Full_Type_Declaration
13846 Nkind (Type_Definition (N)) = N_Record_Definition
13847 and then Interface_Present (Type_Definition (N))
13850 ("completion of private type cannot be an interface", N);
13853 -- Ada 2005 (AI-251): Private extension declaration of a task
13854 -- type or a protected type. This case arises when covering
13855 -- interface types.
13857 elsif Nkind_In (N, N_Task_Type_Declaration,
13858 N_Protected_Type_Declaration)
13862 elsif Nkind (N) /= N_Full_Type_Declaration
13863 or else Nkind (Type_Definition (N)) /= N_Derived_Type_Definition
13866 ("full view of private extension must be an extension", N);
13868 elsif not (Abstract_Present (Parent (Prev)))
13869 and then Abstract_Present (Type_Definition (N))
13872 ("full view of non-abstract extension cannot be abstract", N);
13875 if not In_Private_Part (Current_Scope) then
13877 ("declaration of full view must appear in private part", N);
13880 Copy_And_Swap (Prev, Id);
13881 Set_Has_Private_Declaration (Prev);
13882 Set_Has_Private_Declaration (Id);
13884 -- If no error, propagate freeze_node from private to full view.
13885 -- It may have been generated for an early operational item.
13887 if Present (Freeze_Node (Id))
13888 and then Serious_Errors_Detected = 0
13889 and then No (Full_View (Id))
13891 Set_Freeze_Node (Prev, Freeze_Node (Id));
13892 Set_Freeze_Node (Id, Empty);
13893 Set_First_Rep_Item (Prev, First_Rep_Item (Id));
13896 Set_Full_View (Id, Prev);
13900 -- Verify that full declaration conforms to partial one
13902 if Is_Incomplete_Or_Private_Type (Prev)
13903 and then Present (Discriminant_Specifications (Prev_Par))
13905 if Present (Discriminant_Specifications (N)) then
13906 if Ekind (Prev) = E_Incomplete_Type then
13907 Check_Discriminant_Conformance (N, Prev, Prev);
13909 Check_Discriminant_Conformance (N, Prev, Id);
13914 ("missing discriminants in full type declaration", N);
13916 -- To avoid cascaded errors on subsequent use, share the
13917 -- discriminants of the partial view.
13919 Set_Discriminant_Specifications (N,
13920 Discriminant_Specifications (Prev_Par));
13924 -- A prior untagged partial view can have an associated class-wide
13925 -- type due to use of the class attribute, and in this case the full
13926 -- type must also be tagged. This Ada 95 usage is deprecated in favor
13927 -- of incomplete tagged declarations, but we check for it.
13930 and then (Is_Tagged_Type (Prev)
13931 or else Present (Class_Wide_Type (Prev)))
13933 -- The full declaration is either a tagged type (including
13934 -- a synchronized type that implements interfaces) or a
13935 -- type extension, otherwise this is an error.
13937 if Nkind_In (N, N_Task_Type_Declaration,
13938 N_Protected_Type_Declaration)
13940 if No (Interface_List (N))
13941 and then not Error_Posted (N)
13946 elsif Nkind (Type_Definition (N)) = N_Record_Definition then
13948 -- Indicate that the previous declaration (tagged incomplete
13949 -- or private declaration) requires the same on the full one.
13951 if not Tagged_Present (Type_Definition (N)) then
13953 Set_Is_Tagged_Type (Id);
13954 Set_Primitive_Operations (Id, New_Elmt_List);
13957 elsif Nkind (Type_Definition (N)) = N_Derived_Type_Definition then
13958 if No (Record_Extension_Part (Type_Definition (N))) then
13960 "full declaration of } must be a record extension",
13963 -- Set some attributes to produce a usable full view
13965 Set_Is_Tagged_Type (Id);
13966 Set_Primitive_Operations (Id, New_Elmt_List);
13977 -- New type declaration
13982 end Find_Type_Name;
13984 -------------------------
13985 -- Find_Type_Of_Object --
13986 -------------------------
13988 function Find_Type_Of_Object
13989 (Obj_Def : Node_Id;
13990 Related_Nod : Node_Id) return Entity_Id
13992 Def_Kind : constant Node_Kind := Nkind (Obj_Def);
13993 P : Node_Id := Parent (Obj_Def);
13998 -- If the parent is a component_definition node we climb to the
13999 -- component_declaration node
14001 if Nkind (P) = N_Component_Definition then
14005 -- Case of an anonymous array subtype
14007 if Nkind_In (Def_Kind, N_Constrained_Array_Definition,
14008 N_Unconstrained_Array_Definition)
14011 Array_Type_Declaration (T, Obj_Def);
14013 -- Create an explicit subtype whenever possible
14015 elsif Nkind (P) /= N_Component_Declaration
14016 and then Def_Kind = N_Subtype_Indication
14018 -- Base name of subtype on object name, which will be unique in
14019 -- the current scope.
14021 -- If this is a duplicate declaration, return base type, to avoid
14022 -- generating duplicate anonymous types.
14024 if Error_Posted (P) then
14025 Analyze (Subtype_Mark (Obj_Def));
14026 return Entity (Subtype_Mark (Obj_Def));
14031 (Chars (Defining_Identifier (Related_Nod)), 'S', 0, 'T');
14033 T := Make_Defining_Identifier (Sloc (P), Nam);
14035 Insert_Action (Obj_Def,
14036 Make_Subtype_Declaration (Sloc (P),
14037 Defining_Identifier => T,
14038 Subtype_Indication => Relocate_Node (Obj_Def)));
14040 -- This subtype may need freezing, and this will not be done
14041 -- automatically if the object declaration is not in declarative
14042 -- part. Since this is an object declaration, the type cannot always
14043 -- be frozen here. Deferred constants do not freeze their type
14044 -- (which often enough will be private).
14046 if Nkind (P) = N_Object_Declaration
14047 and then Constant_Present (P)
14048 and then No (Expression (P))
14052 Insert_Actions (Obj_Def, Freeze_Entity (T, Sloc (P)));
14055 -- Ada 2005 AI-406: the object definition in an object declaration
14056 -- can be an access definition.
14058 elsif Def_Kind = N_Access_Definition then
14059 T := Access_Definition (Related_Nod, Obj_Def);
14060 Set_Is_Local_Anonymous_Access (T);
14062 -- Otherwise, the object definition is just a subtype_mark
14065 T := Process_Subtype (Obj_Def, Related_Nod);
14069 end Find_Type_Of_Object;
14071 --------------------------------
14072 -- Find_Type_Of_Subtype_Indic --
14073 --------------------------------
14075 function Find_Type_Of_Subtype_Indic (S : Node_Id) return Entity_Id is
14079 -- Case of subtype mark with a constraint
14081 if Nkind (S) = N_Subtype_Indication then
14082 Find_Type (Subtype_Mark (S));
14083 Typ := Entity (Subtype_Mark (S));
14086 Is_Valid_Constraint_Kind (Ekind (Typ), Nkind (Constraint (S)))
14089 ("incorrect constraint for this kind of type", Constraint (S));
14090 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
14093 -- Otherwise we have a subtype mark without a constraint
14095 elsif Error_Posted (S) then
14096 Rewrite (S, New_Occurrence_Of (Any_Id, Sloc (S)));
14104 -- Check No_Wide_Characters restriction
14106 if Typ = Standard_Wide_Character
14107 or else Typ = Standard_Wide_Wide_Character
14108 or else Typ = Standard_Wide_String
14109 or else Typ = Standard_Wide_Wide_String
14111 Check_Restriction (No_Wide_Characters, S);
14115 end Find_Type_Of_Subtype_Indic;
14117 -------------------------------------
14118 -- Floating_Point_Type_Declaration --
14119 -------------------------------------
14121 procedure Floating_Point_Type_Declaration (T : Entity_Id; Def : Node_Id) is
14122 Digs : constant Node_Id := Digits_Expression (Def);
14124 Base_Typ : Entity_Id;
14125 Implicit_Base : Entity_Id;
14128 function Can_Derive_From (E : Entity_Id) return Boolean;
14129 -- Find if given digits value allows derivation from specified type
14131 ---------------------
14132 -- Can_Derive_From --
14133 ---------------------
14135 function Can_Derive_From (E : Entity_Id) return Boolean is
14136 Spec : constant Entity_Id := Real_Range_Specification (Def);
14139 if Digs_Val > Digits_Value (E) then
14143 if Present (Spec) then
14144 if Expr_Value_R (Type_Low_Bound (E)) >
14145 Expr_Value_R (Low_Bound (Spec))
14150 if Expr_Value_R (Type_High_Bound (E)) <
14151 Expr_Value_R (High_Bound (Spec))
14158 end Can_Derive_From;
14160 -- Start of processing for Floating_Point_Type_Declaration
14163 Check_Restriction (No_Floating_Point, Def);
14165 -- Create an implicit base type
14168 Create_Itype (E_Floating_Point_Type, Parent (Def), T, 'B');
14170 -- Analyze and verify digits value
14172 Analyze_And_Resolve (Digs, Any_Integer);
14173 Check_Digits_Expression (Digs);
14174 Digs_Val := Expr_Value (Digs);
14176 -- Process possible range spec and find correct type to derive from
14178 Process_Real_Range_Specification (Def);
14180 if Can_Derive_From (Standard_Short_Float) then
14181 Base_Typ := Standard_Short_Float;
14182 elsif Can_Derive_From (Standard_Float) then
14183 Base_Typ := Standard_Float;
14184 elsif Can_Derive_From (Standard_Long_Float) then
14185 Base_Typ := Standard_Long_Float;
14186 elsif Can_Derive_From (Standard_Long_Long_Float) then
14187 Base_Typ := Standard_Long_Long_Float;
14189 -- If we can't derive from any existing type, use long_long_float
14190 -- and give appropriate message explaining the problem.
14193 Base_Typ := Standard_Long_Long_Float;
14195 if Digs_Val >= Digits_Value (Standard_Long_Long_Float) then
14196 Error_Msg_Uint_1 := Digits_Value (Standard_Long_Long_Float);
14197 Error_Msg_N ("digits value out of range, maximum is ^", Digs);
14201 ("range too large for any predefined type",
14202 Real_Range_Specification (Def));
14206 -- If there are bounds given in the declaration use them as the bounds
14207 -- of the type, otherwise use the bounds of the predefined base type
14208 -- that was chosen based on the Digits value.
14210 if Present (Real_Range_Specification (Def)) then
14211 Set_Scalar_Range (T, Real_Range_Specification (Def));
14212 Set_Is_Constrained (T);
14214 -- The bounds of this range must be converted to machine numbers
14215 -- in accordance with RM 4.9(38).
14217 Bound := Type_Low_Bound (T);
14219 if Nkind (Bound) = N_Real_Literal then
14221 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
14222 Set_Is_Machine_Number (Bound);
14225 Bound := Type_High_Bound (T);
14227 if Nkind (Bound) = N_Real_Literal then
14229 (Bound, Machine (Base_Typ, Realval (Bound), Round, Bound));
14230 Set_Is_Machine_Number (Bound);
14234 Set_Scalar_Range (T, Scalar_Range (Base_Typ));
14237 -- Complete definition of implicit base and declared first subtype
14239 Set_Etype (Implicit_Base, Base_Typ);
14241 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
14242 Set_Size_Info (Implicit_Base, (Base_Typ));
14243 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
14244 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
14245 Set_Digits_Value (Implicit_Base, Digits_Value (Base_Typ));
14246 Set_Vax_Float (Implicit_Base, Vax_Float (Base_Typ));
14248 Set_Ekind (T, E_Floating_Point_Subtype);
14249 Set_Etype (T, Implicit_Base);
14251 Set_Size_Info (T, (Implicit_Base));
14252 Set_RM_Size (T, RM_Size (Implicit_Base));
14253 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
14254 Set_Digits_Value (T, Digs_Val);
14255 end Floating_Point_Type_Declaration;
14257 ----------------------------
14258 -- Get_Discriminant_Value --
14259 ----------------------------
14261 -- This is the situation:
14263 -- There is a non-derived type
14265 -- type T0 (Dx, Dy, Dz...)
14267 -- There are zero or more levels of derivation, with each derivation
14268 -- either purely inheriting the discriminants, or defining its own.
14270 -- type Ti is new Ti-1
14272 -- type Ti (Dw) is new Ti-1(Dw, 1, X+Y)
14274 -- subtype Ti is ...
14276 -- The subtype issue is avoided by the use of Original_Record_Component,
14277 -- and the fact that derived subtypes also derive the constraints.
14279 -- This chain leads back from
14281 -- Typ_For_Constraint
14283 -- Typ_For_Constraint has discriminants, and the value for each
14284 -- discriminant is given by its corresponding Elmt of Constraints.
14286 -- Discriminant is some discriminant in this hierarchy
14288 -- We need to return its value
14290 -- We do this by recursively searching each level, and looking for
14291 -- Discriminant. Once we get to the bottom, we start backing up
14292 -- returning the value for it which may in turn be a discriminant
14293 -- further up, so on the backup we continue the substitution.
14295 function Get_Discriminant_Value
14296 (Discriminant : Entity_Id;
14297 Typ_For_Constraint : Entity_Id;
14298 Constraint : Elist_Id) return Node_Id
14300 function Search_Derivation_Levels
14302 Discrim_Values : Elist_Id;
14303 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id;
14304 -- This is the routine that performs the recursive search of levels
14305 -- as described above.
14307 ------------------------------
14308 -- Search_Derivation_Levels --
14309 ------------------------------
14311 function Search_Derivation_Levels
14313 Discrim_Values : Elist_Id;
14314 Stored_Discrim_Values : Boolean) return Node_Or_Entity_Id
14318 Result : Node_Or_Entity_Id;
14319 Result_Entity : Node_Id;
14322 -- If inappropriate type, return Error, this happens only in
14323 -- cascaded error situations, and we want to avoid a blow up.
14325 if not Is_Composite_Type (Ti) or else Is_Array_Type (Ti) then
14329 -- Look deeper if possible. Use Stored_Constraints only for
14330 -- untagged types. For tagged types use the given constraint.
14331 -- This asymmetry needs explanation???
14333 if not Stored_Discrim_Values
14334 and then Present (Stored_Constraint (Ti))
14335 and then not Is_Tagged_Type (Ti)
14338 Search_Derivation_Levels (Ti, Stored_Constraint (Ti), True);
14341 Td : constant Entity_Id := Etype (Ti);
14345 Result := Discriminant;
14348 if Present (Stored_Constraint (Ti)) then
14350 Search_Derivation_Levels
14351 (Td, Stored_Constraint (Ti), True);
14354 Search_Derivation_Levels
14355 (Td, Discrim_Values, Stored_Discrim_Values);
14361 -- Extra underlying places to search, if not found above. For
14362 -- concurrent types, the relevant discriminant appears in the
14363 -- corresponding record. For a type derived from a private type
14364 -- without discriminant, the full view inherits the discriminants
14365 -- of the full view of the parent.
14367 if Result = Discriminant then
14368 if Is_Concurrent_Type (Ti)
14369 and then Present (Corresponding_Record_Type (Ti))
14372 Search_Derivation_Levels (
14373 Corresponding_Record_Type (Ti),
14375 Stored_Discrim_Values);
14377 elsif Is_Private_Type (Ti)
14378 and then not Has_Discriminants (Ti)
14379 and then Present (Full_View (Ti))
14380 and then Etype (Full_View (Ti)) /= Ti
14383 Search_Derivation_Levels (
14386 Stored_Discrim_Values);
14390 -- If Result is not a (reference to a) discriminant, return it,
14391 -- otherwise set Result_Entity to the discriminant.
14393 if Nkind (Result) = N_Defining_Identifier then
14394 pragma Assert (Result = Discriminant);
14395 Result_Entity := Result;
14398 if not Denotes_Discriminant (Result) then
14402 Result_Entity := Entity (Result);
14405 -- See if this level of derivation actually has discriminants
14406 -- because tagged derivations can add them, hence the lower
14407 -- levels need not have any.
14409 if not Has_Discriminants (Ti) then
14413 -- Scan Ti's discriminants for Result_Entity,
14414 -- and return its corresponding value, if any.
14416 Result_Entity := Original_Record_Component (Result_Entity);
14418 Assoc := First_Elmt (Discrim_Values);
14420 if Stored_Discrim_Values then
14421 Disc := First_Stored_Discriminant (Ti);
14423 Disc := First_Discriminant (Ti);
14426 while Present (Disc) loop
14427 pragma Assert (Present (Assoc));
14429 if Original_Record_Component (Disc) = Result_Entity then
14430 return Node (Assoc);
14435 if Stored_Discrim_Values then
14436 Next_Stored_Discriminant (Disc);
14438 Next_Discriminant (Disc);
14442 -- Could not find it
14445 end Search_Derivation_Levels;
14449 Result : Node_Or_Entity_Id;
14451 -- Start of processing for Get_Discriminant_Value
14454 -- ??? This routine is a gigantic mess and will be deleted. For the
14455 -- time being just test for the trivial case before calling recurse.
14457 if Base_Type (Scope (Discriminant)) = Base_Type (Typ_For_Constraint) then
14463 D := First_Discriminant (Typ_For_Constraint);
14464 E := First_Elmt (Constraint);
14465 while Present (D) loop
14466 if Chars (D) = Chars (Discriminant) then
14470 Next_Discriminant (D);
14476 Result := Search_Derivation_Levels
14477 (Typ_For_Constraint, Constraint, False);
14479 -- ??? hack to disappear when this routine is gone
14481 if Nkind (Result) = N_Defining_Identifier then
14487 D := First_Discriminant (Typ_For_Constraint);
14488 E := First_Elmt (Constraint);
14489 while Present (D) loop
14490 if Corresponding_Discriminant (D) = Discriminant then
14494 Next_Discriminant (D);
14500 pragma Assert (Nkind (Result) /= N_Defining_Identifier);
14502 end Get_Discriminant_Value;
14504 --------------------------
14505 -- Has_Range_Constraint --
14506 --------------------------
14508 function Has_Range_Constraint (N : Node_Id) return Boolean is
14509 C : constant Node_Id := Constraint (N);
14512 if Nkind (C) = N_Range_Constraint then
14515 elsif Nkind (C) = N_Digits_Constraint then
14517 Is_Decimal_Fixed_Point_Type (Entity (Subtype_Mark (N)))
14519 Present (Range_Constraint (C));
14521 elsif Nkind (C) = N_Delta_Constraint then
14522 return Present (Range_Constraint (C));
14527 end Has_Range_Constraint;
14529 ------------------------
14530 -- Inherit_Components --
14531 ------------------------
14533 function Inherit_Components
14535 Parent_Base : Entity_Id;
14536 Derived_Base : Entity_Id;
14537 Is_Tagged : Boolean;
14538 Inherit_Discr : Boolean;
14539 Discs : Elist_Id) return Elist_Id
14541 Assoc_List : constant Elist_Id := New_Elmt_List;
14543 procedure Inherit_Component
14544 (Old_C : Entity_Id;
14545 Plain_Discrim : Boolean := False;
14546 Stored_Discrim : Boolean := False);
14547 -- Inherits component Old_C from Parent_Base to the Derived_Base. If
14548 -- Plain_Discrim is True, Old_C is a discriminant. If Stored_Discrim is
14549 -- True, Old_C is a stored discriminant. If they are both false then
14550 -- Old_C is a regular component.
14552 -----------------------
14553 -- Inherit_Component --
14554 -----------------------
14556 procedure Inherit_Component
14557 (Old_C : Entity_Id;
14558 Plain_Discrim : Boolean := False;
14559 Stored_Discrim : Boolean := False)
14561 New_C : constant Entity_Id := New_Copy (Old_C);
14563 Discrim : Entity_Id;
14564 Corr_Discrim : Entity_Id;
14567 pragma Assert (not Is_Tagged or else not Stored_Discrim);
14569 Set_Parent (New_C, Parent (Old_C));
14571 -- Regular discriminants and components must be inserted in the scope
14572 -- of the Derived_Base. Do it here.
14574 if not Stored_Discrim then
14575 Enter_Name (New_C);
14578 -- For tagged types the Original_Record_Component must point to
14579 -- whatever this field was pointing to in the parent type. This has
14580 -- already been achieved by the call to New_Copy above.
14582 if not Is_Tagged then
14583 Set_Original_Record_Component (New_C, New_C);
14586 -- If we have inherited a component then see if its Etype contains
14587 -- references to Parent_Base discriminants. In this case, replace
14588 -- these references with the constraints given in Discs. We do not
14589 -- do this for the partial view of private types because this is
14590 -- not needed (only the components of the full view will be used
14591 -- for code generation) and cause problem. We also avoid this
14592 -- transformation in some error situations.
14594 if Ekind (New_C) = E_Component then
14595 if (Is_Private_Type (Derived_Base)
14596 and then not Is_Generic_Type (Derived_Base))
14597 or else (Is_Empty_Elmt_List (Discs)
14598 and then not Expander_Active)
14600 Set_Etype (New_C, Etype (Old_C));
14603 -- The current component introduces a circularity of the
14606 -- limited with Pack_2;
14607 -- package Pack_1 is
14608 -- type T_1 is tagged record
14609 -- Comp : access Pack_2.T_2;
14615 -- package Pack_2 is
14616 -- type T_2 is new Pack_1.T_1 with ...;
14621 Constrain_Component_Type
14622 (Old_C, Derived_Base, N, Parent_Base, Discs));
14626 -- In derived tagged types it is illegal to reference a non
14627 -- discriminant component in the parent type. To catch this, mark
14628 -- these components with an Ekind of E_Void. This will be reset in
14629 -- Record_Type_Definition after processing the record extension of
14630 -- the derived type.
14632 -- If the declaration is a private extension, there is no further
14633 -- record extension to process, and the components retain their
14634 -- current kind, because they are visible at this point.
14636 if Is_Tagged and then Ekind (New_C) = E_Component
14637 and then Nkind (N) /= N_Private_Extension_Declaration
14639 Set_Ekind (New_C, E_Void);
14642 if Plain_Discrim then
14643 Set_Corresponding_Discriminant (New_C, Old_C);
14644 Build_Discriminal (New_C);
14646 -- If we are explicitly inheriting a stored discriminant it will be
14647 -- completely hidden.
14649 elsif Stored_Discrim then
14650 Set_Corresponding_Discriminant (New_C, Empty);
14651 Set_Discriminal (New_C, Empty);
14652 Set_Is_Completely_Hidden (New_C);
14654 -- Set the Original_Record_Component of each discriminant in the
14655 -- derived base to point to the corresponding stored that we just
14658 Discrim := First_Discriminant (Derived_Base);
14659 while Present (Discrim) loop
14660 Corr_Discrim := Corresponding_Discriminant (Discrim);
14662 -- Corr_Discrim could be missing in an error situation
14664 if Present (Corr_Discrim)
14665 and then Original_Record_Component (Corr_Discrim) = Old_C
14667 Set_Original_Record_Component (Discrim, New_C);
14670 Next_Discriminant (Discrim);
14673 Append_Entity (New_C, Derived_Base);
14676 if not Is_Tagged then
14677 Append_Elmt (Old_C, Assoc_List);
14678 Append_Elmt (New_C, Assoc_List);
14680 end Inherit_Component;
14682 -- Variables local to Inherit_Component
14684 Loc : constant Source_Ptr := Sloc (N);
14686 Parent_Discrim : Entity_Id;
14687 Stored_Discrim : Entity_Id;
14689 Component : Entity_Id;
14691 -- Start of processing for Inherit_Components
14694 if not Is_Tagged then
14695 Append_Elmt (Parent_Base, Assoc_List);
14696 Append_Elmt (Derived_Base, Assoc_List);
14699 -- Inherit parent discriminants if needed
14701 if Inherit_Discr then
14702 Parent_Discrim := First_Discriminant (Parent_Base);
14703 while Present (Parent_Discrim) loop
14704 Inherit_Component (Parent_Discrim, Plain_Discrim => True);
14705 Next_Discriminant (Parent_Discrim);
14709 -- Create explicit stored discrims for untagged types when necessary
14711 if not Has_Unknown_Discriminants (Derived_Base)
14712 and then Has_Discriminants (Parent_Base)
14713 and then not Is_Tagged
14716 or else First_Discriminant (Parent_Base) /=
14717 First_Stored_Discriminant (Parent_Base))
14719 Stored_Discrim := First_Stored_Discriminant (Parent_Base);
14720 while Present (Stored_Discrim) loop
14721 Inherit_Component (Stored_Discrim, Stored_Discrim => True);
14722 Next_Stored_Discriminant (Stored_Discrim);
14726 -- See if we can apply the second transformation for derived types, as
14727 -- explained in point 6. in the comments above Build_Derived_Record_Type
14728 -- This is achieved by appending Derived_Base discriminants into Discs,
14729 -- which has the side effect of returning a non empty Discs list to the
14730 -- caller of Inherit_Components, which is what we want. This must be
14731 -- done for private derived types if there are explicit stored
14732 -- discriminants, to ensure that we can retrieve the values of the
14733 -- constraints provided in the ancestors.
14736 and then Is_Empty_Elmt_List (Discs)
14737 and then Present (First_Discriminant (Derived_Base))
14739 (not Is_Private_Type (Derived_Base)
14740 or else Is_Completely_Hidden
14741 (First_Stored_Discriminant (Derived_Base))
14742 or else Is_Generic_Type (Derived_Base))
14744 D := First_Discriminant (Derived_Base);
14745 while Present (D) loop
14746 Append_Elmt (New_Reference_To (D, Loc), Discs);
14747 Next_Discriminant (D);
14751 -- Finally, inherit non-discriminant components unless they are not
14752 -- visible because defined or inherited from the full view of the
14753 -- parent. Don't inherit the _parent field of the parent type.
14755 Component := First_Entity (Parent_Base);
14756 while Present (Component) loop
14758 -- Ada 2005 (AI-251): Do not inherit components associated with
14759 -- secondary tags of the parent.
14761 if Ekind (Component) = E_Component
14762 and then Present (Related_Type (Component))
14766 elsif Ekind (Component) /= E_Component
14767 or else Chars (Component) = Name_uParent
14771 -- If the derived type is within the parent type's declarative
14772 -- region, then the components can still be inherited even though
14773 -- they aren't visible at this point. This can occur for cases
14774 -- such as within public child units where the components must
14775 -- become visible upon entering the child unit's private part.
14777 elsif not Is_Visible_Component (Component)
14778 and then not In_Open_Scopes (Scope (Parent_Base))
14782 elsif Ekind_In (Derived_Base, E_Private_Type,
14783 E_Limited_Private_Type)
14788 Inherit_Component (Component);
14791 Next_Entity (Component);
14794 -- For tagged derived types, inherited discriminants cannot be used in
14795 -- component declarations of the record extension part. To achieve this
14796 -- we mark the inherited discriminants as not visible.
14798 if Is_Tagged and then Inherit_Discr then
14799 D := First_Discriminant (Derived_Base);
14800 while Present (D) loop
14801 Set_Is_Immediately_Visible (D, False);
14802 Next_Discriminant (D);
14807 end Inherit_Components;
14809 -----------------------
14810 -- Is_Null_Extension --
14811 -----------------------
14813 function Is_Null_Extension (T : Entity_Id) return Boolean is
14814 Type_Decl : constant Node_Id := Parent (Base_Type (T));
14815 Comp_List : Node_Id;
14819 if Nkind (Type_Decl) /= N_Full_Type_Declaration
14820 or else not Is_Tagged_Type (T)
14821 or else Nkind (Type_Definition (Type_Decl)) /=
14822 N_Derived_Type_Definition
14823 or else No (Record_Extension_Part (Type_Definition (Type_Decl)))
14829 Component_List (Record_Extension_Part (Type_Definition (Type_Decl)));
14831 if Present (Discriminant_Specifications (Type_Decl)) then
14834 elsif Present (Comp_List)
14835 and then Is_Non_Empty_List (Component_Items (Comp_List))
14837 Comp := First (Component_Items (Comp_List));
14839 -- Only user-defined components are relevant. The component list
14840 -- may also contain a parent component and internal components
14841 -- corresponding to secondary tags, but these do not determine
14842 -- whether this is a null extension.
14844 while Present (Comp) loop
14845 if Comes_From_Source (Comp) then
14856 end Is_Null_Extension;
14858 --------------------
14859 -- Is_Progenitor --
14860 --------------------
14862 function Is_Progenitor
14863 (Iface : Entity_Id;
14864 Typ : Entity_Id) return Boolean
14867 return Implements_Interface (Typ, Iface,
14868 Exclude_Parents => True);
14871 ------------------------------
14872 -- Is_Valid_Constraint_Kind --
14873 ------------------------------
14875 function Is_Valid_Constraint_Kind
14876 (T_Kind : Type_Kind;
14877 Constraint_Kind : Node_Kind) return Boolean
14881 when Enumeration_Kind |
14883 return Constraint_Kind = N_Range_Constraint;
14885 when Decimal_Fixed_Point_Kind =>
14886 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
14887 N_Range_Constraint);
14889 when Ordinary_Fixed_Point_Kind =>
14890 return Nkind_In (Constraint_Kind, N_Delta_Constraint,
14891 N_Range_Constraint);
14894 return Nkind_In (Constraint_Kind, N_Digits_Constraint,
14895 N_Range_Constraint);
14902 E_Incomplete_Type |
14905 return Constraint_Kind = N_Index_Or_Discriminant_Constraint;
14908 return True; -- Error will be detected later
14910 end Is_Valid_Constraint_Kind;
14912 --------------------------
14913 -- Is_Visible_Component --
14914 --------------------------
14916 function Is_Visible_Component (C : Entity_Id) return Boolean is
14917 Original_Comp : Entity_Id := Empty;
14918 Original_Scope : Entity_Id;
14919 Type_Scope : Entity_Id;
14921 function Is_Local_Type (Typ : Entity_Id) return Boolean;
14922 -- Check whether parent type of inherited component is declared locally,
14923 -- possibly within a nested package or instance. The current scope is
14924 -- the derived record itself.
14926 -------------------
14927 -- Is_Local_Type --
14928 -------------------
14930 function Is_Local_Type (Typ : Entity_Id) return Boolean is
14934 Scop := Scope (Typ);
14935 while Present (Scop)
14936 and then Scop /= Standard_Standard
14938 if Scop = Scope (Current_Scope) then
14942 Scop := Scope (Scop);
14948 -- Start of processing for Is_Visible_Component
14951 if Ekind_In (C, E_Component, E_Discriminant) then
14952 Original_Comp := Original_Record_Component (C);
14955 if No (Original_Comp) then
14957 -- Premature usage, or previous error
14962 Original_Scope := Scope (Original_Comp);
14963 Type_Scope := Scope (Base_Type (Scope (C)));
14966 -- This test only concerns tagged types
14968 if not Is_Tagged_Type (Original_Scope) then
14971 -- If it is _Parent or _Tag, there is no visibility issue
14973 elsif not Comes_From_Source (Original_Comp) then
14976 -- If we are in the body of an instantiation, the component is visible
14977 -- even when the parent type (possibly defined in an enclosing unit or
14978 -- in a parent unit) might not.
14980 elsif In_Instance_Body then
14983 -- Discriminants are always visible
14985 elsif Ekind (Original_Comp) = E_Discriminant
14986 and then not Has_Unknown_Discriminants (Original_Scope)
14990 -- If the component has been declared in an ancestor which is currently
14991 -- a private type, then it is not visible. The same applies if the
14992 -- component's containing type is not in an open scope and the original
14993 -- component's enclosing type is a visible full view of a private type
14994 -- (which can occur in cases where an attempt is being made to reference
14995 -- a component in a sibling package that is inherited from a visible
14996 -- component of a type in an ancestor package; the component in the
14997 -- sibling package should not be visible even though the component it
14998 -- inherited from is visible). This does not apply however in the case
14999 -- where the scope of the type is a private child unit, or when the
15000 -- parent comes from a local package in which the ancestor is currently
15001 -- visible. The latter suppression of visibility is needed for cases
15002 -- that are tested in B730006.
15004 elsif Is_Private_Type (Original_Scope)
15006 (not Is_Private_Descendant (Type_Scope)
15007 and then not In_Open_Scopes (Type_Scope)
15008 and then Has_Private_Declaration (Original_Scope))
15010 -- If the type derives from an entity in a formal package, there
15011 -- are no additional visible components.
15013 if Nkind (Original_Node (Unit_Declaration_Node (Type_Scope))) =
15014 N_Formal_Package_Declaration
15018 -- if we are not in the private part of the current package, there
15019 -- are no additional visible components.
15021 elsif Ekind (Scope (Current_Scope)) = E_Package
15022 and then not In_Private_Part (Scope (Current_Scope))
15027 Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
15028 and then In_Open_Scopes (Scope (Original_Scope))
15029 and then Is_Local_Type (Type_Scope);
15032 -- There is another weird way in which a component may be invisible
15033 -- when the private and the full view are not derived from the same
15034 -- ancestor. Here is an example :
15036 -- type A1 is tagged record F1 : integer; end record;
15037 -- type A2 is new A1 with record F2 : integer; end record;
15038 -- type T is new A1 with private;
15040 -- type T is new A2 with null record;
15042 -- In this case, the full view of T inherits F1 and F2 but the private
15043 -- view inherits only F1
15047 Ancestor : Entity_Id := Scope (C);
15051 if Ancestor = Original_Scope then
15053 elsif Ancestor = Etype (Ancestor) then
15057 Ancestor := Etype (Ancestor);
15061 end Is_Visible_Component;
15063 --------------------------
15064 -- Make_Class_Wide_Type --
15065 --------------------------
15067 procedure Make_Class_Wide_Type (T : Entity_Id) is
15068 CW_Type : Entity_Id;
15070 Next_E : Entity_Id;
15073 -- The class wide type can have been defined by the partial view, in
15074 -- which case everything is already done.
15076 if Present (Class_Wide_Type (T)) then
15081 New_External_Entity (E_Void, Scope (T), Sloc (T), T, 'C', 0, 'T');
15083 -- Inherit root type characteristics
15085 CW_Name := Chars (CW_Type);
15086 Next_E := Next_Entity (CW_Type);
15087 Copy_Node (T, CW_Type);
15088 Set_Comes_From_Source (CW_Type, False);
15089 Set_Chars (CW_Type, CW_Name);
15090 Set_Parent (CW_Type, Parent (T));
15091 Set_Next_Entity (CW_Type, Next_E);
15093 -- Ensure we have a new freeze node for the class-wide type. The partial
15094 -- view may have freeze action of its own, requiring a proper freeze
15095 -- node, and the same freeze node cannot be shared between the two
15098 Set_Has_Delayed_Freeze (CW_Type);
15099 Set_Freeze_Node (CW_Type, Empty);
15101 -- Customize the class-wide type: It has no prim. op., it cannot be
15102 -- abstract and its Etype points back to the specific root type.
15104 Set_Ekind (CW_Type, E_Class_Wide_Type);
15105 Set_Is_Tagged_Type (CW_Type, True);
15106 Set_Primitive_Operations (CW_Type, New_Elmt_List);
15107 Set_Is_Abstract_Type (CW_Type, False);
15108 Set_Is_Constrained (CW_Type, False);
15109 Set_Is_First_Subtype (CW_Type, Is_First_Subtype (T));
15111 if Ekind (T) = E_Class_Wide_Subtype then
15112 Set_Etype (CW_Type, Etype (Base_Type (T)));
15114 Set_Etype (CW_Type, T);
15117 -- If this is the class_wide type of a constrained subtype, it does
15118 -- not have discriminants.
15120 Set_Has_Discriminants (CW_Type,
15121 Has_Discriminants (T) and then not Is_Constrained (T));
15123 Set_Has_Unknown_Discriminants (CW_Type, True);
15124 Set_Class_Wide_Type (T, CW_Type);
15125 Set_Equivalent_Type (CW_Type, Empty);
15127 -- The class-wide type of a class-wide type is itself (RM 3.9(14))
15129 Set_Class_Wide_Type (CW_Type, CW_Type);
15130 end Make_Class_Wide_Type;
15136 procedure Make_Index
15138 Related_Nod : Node_Id;
15139 Related_Id : Entity_Id := Empty;
15140 Suffix_Index : Nat := 1)
15144 Def_Id : Entity_Id := Empty;
15145 Found : Boolean := False;
15148 -- For a discrete range used in a constrained array definition and
15149 -- defined by a range, an implicit conversion to the predefined type
15150 -- INTEGER is assumed if each bound is either a numeric literal, a named
15151 -- number, or an attribute, and the type of both bounds (prior to the
15152 -- implicit conversion) is the type universal_integer. Otherwise, both
15153 -- bounds must be of the same discrete type, other than universal
15154 -- integer; this type must be determinable independently of the
15155 -- context, but using the fact that the type must be discrete and that
15156 -- both bounds must have the same type.
15158 -- Character literals also have a universal type in the absence of
15159 -- of additional context, and are resolved to Standard_Character.
15161 if Nkind (I) = N_Range then
15163 -- The index is given by a range constraint. The bounds are known
15164 -- to be of a consistent type.
15166 if not Is_Overloaded (I) then
15169 -- For universal bounds, choose the specific predefined type
15171 if T = Universal_Integer then
15172 T := Standard_Integer;
15174 elsif T = Any_Character then
15175 Ambiguous_Character (Low_Bound (I));
15177 T := Standard_Character;
15180 -- The node may be overloaded because some user-defined operators
15181 -- are available, but if a universal interpretation exists it is
15182 -- also the selected one.
15184 elsif Universal_Interpretation (I) = Universal_Integer then
15185 T := Standard_Integer;
15191 Ind : Interp_Index;
15195 Get_First_Interp (I, Ind, It);
15196 while Present (It.Typ) loop
15197 if Is_Discrete_Type (It.Typ) then
15200 and then not Covers (It.Typ, T)
15201 and then not Covers (T, It.Typ)
15203 Error_Msg_N ("ambiguous bounds in discrete range", I);
15211 Get_Next_Interp (Ind, It);
15214 if T = Any_Type then
15215 Error_Msg_N ("discrete type required for range", I);
15216 Set_Etype (I, Any_Type);
15219 elsif T = Universal_Integer then
15220 T := Standard_Integer;
15225 if not Is_Discrete_Type (T) then
15226 Error_Msg_N ("discrete type required for range", I);
15227 Set_Etype (I, Any_Type);
15231 if Nkind (Low_Bound (I)) = N_Attribute_Reference
15232 and then Attribute_Name (Low_Bound (I)) = Name_First
15233 and then Is_Entity_Name (Prefix (Low_Bound (I)))
15234 and then Is_Type (Entity (Prefix (Low_Bound (I))))
15235 and then Is_Discrete_Type (Entity (Prefix (Low_Bound (I))))
15237 -- The type of the index will be the type of the prefix, as long
15238 -- as the upper bound is 'Last of the same type.
15240 Def_Id := Entity (Prefix (Low_Bound (I)));
15242 if Nkind (High_Bound (I)) /= N_Attribute_Reference
15243 or else Attribute_Name (High_Bound (I)) /= Name_Last
15244 or else not Is_Entity_Name (Prefix (High_Bound (I)))
15245 or else Entity (Prefix (High_Bound (I))) /= Def_Id
15252 Process_Range_Expr_In_Decl (R, T);
15254 elsif Nkind (I) = N_Subtype_Indication then
15256 -- The index is given by a subtype with a range constraint
15258 T := Base_Type (Entity (Subtype_Mark (I)));
15260 if not Is_Discrete_Type (T) then
15261 Error_Msg_N ("discrete type required for range", I);
15262 Set_Etype (I, Any_Type);
15266 R := Range_Expression (Constraint (I));
15269 Process_Range_Expr_In_Decl (R, Entity (Subtype_Mark (I)));
15271 elsif Nkind (I) = N_Attribute_Reference then
15273 -- The parser guarantees that the attribute is a RANGE attribute
15275 -- If the node denotes the range of a type mark, that is also the
15276 -- resulting type, and we do no need to create an Itype for it.
15278 if Is_Entity_Name (Prefix (I))
15279 and then Comes_From_Source (I)
15280 and then Is_Type (Entity (Prefix (I)))
15281 and then Is_Discrete_Type (Entity (Prefix (I)))
15283 Def_Id := Entity (Prefix (I));
15286 Analyze_And_Resolve (I);
15290 -- If none of the above, must be a subtype. We convert this to a
15291 -- range attribute reference because in the case of declared first
15292 -- named subtypes, the types in the range reference can be different
15293 -- from the type of the entity. A range attribute normalizes the
15294 -- reference and obtains the correct types for the bounds.
15296 -- This transformation is in the nature of an expansion, is only
15297 -- done if expansion is active. In particular, it is not done on
15298 -- formal generic types, because we need to retain the name of the
15299 -- original index for instantiation purposes.
15302 if not Is_Entity_Name (I) or else not Is_Type (Entity (I)) then
15303 Error_Msg_N ("invalid subtype mark in discrete range ", I);
15304 Set_Etype (I, Any_Integer);
15308 -- The type mark may be that of an incomplete type. It is only
15309 -- now that we can get the full view, previous analysis does
15310 -- not look specifically for a type mark.
15312 Set_Entity (I, Get_Full_View (Entity (I)));
15313 Set_Etype (I, Entity (I));
15314 Def_Id := Entity (I);
15316 if not Is_Discrete_Type (Def_Id) then
15317 Error_Msg_N ("discrete type required for index", I);
15318 Set_Etype (I, Any_Type);
15323 if Expander_Active then
15325 Make_Attribute_Reference (Sloc (I),
15326 Attribute_Name => Name_Range,
15327 Prefix => Relocate_Node (I)));
15329 -- The original was a subtype mark that does not freeze. This
15330 -- means that the rewritten version must not freeze either.
15332 Set_Must_Not_Freeze (I);
15333 Set_Must_Not_Freeze (Prefix (I));
15335 -- Is order critical??? if so, document why, if not
15336 -- use Analyze_And_Resolve
15338 Analyze_And_Resolve (I);
15342 -- If expander is inactive, type is legal, nothing else to construct
15349 if not Is_Discrete_Type (T) then
15350 Error_Msg_N ("discrete type required for range", I);
15351 Set_Etype (I, Any_Type);
15354 elsif T = Any_Type then
15355 Set_Etype (I, Any_Type);
15359 -- We will now create the appropriate Itype to describe the range, but
15360 -- first a check. If we originally had a subtype, then we just label
15361 -- the range with this subtype. Not only is there no need to construct
15362 -- a new subtype, but it is wrong to do so for two reasons:
15364 -- 1. A legality concern, if we have a subtype, it must not freeze,
15365 -- and the Itype would cause freezing incorrectly
15367 -- 2. An efficiency concern, if we created an Itype, it would not be
15368 -- recognized as the same type for the purposes of eliminating
15369 -- checks in some circumstances.
15371 -- We signal this case by setting the subtype entity in Def_Id
15373 if No (Def_Id) then
15375 Create_Itype (E_Void, Related_Nod, Related_Id, 'D', Suffix_Index);
15376 Set_Etype (Def_Id, Base_Type (T));
15378 if Is_Signed_Integer_Type (T) then
15379 Set_Ekind (Def_Id, E_Signed_Integer_Subtype);
15381 elsif Is_Modular_Integer_Type (T) then
15382 Set_Ekind (Def_Id, E_Modular_Integer_Subtype);
15385 Set_Ekind (Def_Id, E_Enumeration_Subtype);
15386 Set_Is_Character_Type (Def_Id, Is_Character_Type (T));
15387 Set_First_Literal (Def_Id, First_Literal (T));
15390 Set_Size_Info (Def_Id, (T));
15391 Set_RM_Size (Def_Id, RM_Size (T));
15392 Set_First_Rep_Item (Def_Id, First_Rep_Item (T));
15394 Set_Scalar_Range (Def_Id, R);
15395 Conditional_Delay (Def_Id, T);
15397 -- In the subtype indication case, if the immediate parent of the
15398 -- new subtype is non-static, then the subtype we create is non-
15399 -- static, even if its bounds are static.
15401 if Nkind (I) = N_Subtype_Indication
15402 and then not Is_Static_Subtype (Entity (Subtype_Mark (I)))
15404 Set_Is_Non_Static_Subtype (Def_Id);
15408 -- Final step is to label the index with this constructed type
15410 Set_Etype (I, Def_Id);
15413 ------------------------------
15414 -- Modular_Type_Declaration --
15415 ------------------------------
15417 procedure Modular_Type_Declaration (T : Entity_Id; Def : Node_Id) is
15418 Mod_Expr : constant Node_Id := Expression (Def);
15421 procedure Set_Modular_Size (Bits : Int);
15422 -- Sets RM_Size to Bits, and Esize to normal word size above this
15424 ----------------------
15425 -- Set_Modular_Size --
15426 ----------------------
15428 procedure Set_Modular_Size (Bits : Int) is
15430 Set_RM_Size (T, UI_From_Int (Bits));
15435 elsif Bits <= 16 then
15436 Init_Esize (T, 16);
15438 elsif Bits <= 32 then
15439 Init_Esize (T, 32);
15442 Init_Esize (T, System_Max_Binary_Modulus_Power);
15445 if not Non_Binary_Modulus (T)
15446 and then Esize (T) = RM_Size (T)
15448 Set_Is_Known_Valid (T);
15450 end Set_Modular_Size;
15452 -- Start of processing for Modular_Type_Declaration
15455 Analyze_And_Resolve (Mod_Expr, Any_Integer);
15457 Set_Ekind (T, E_Modular_Integer_Type);
15458 Init_Alignment (T);
15459 Set_Is_Constrained (T);
15461 if not Is_OK_Static_Expression (Mod_Expr) then
15462 Flag_Non_Static_Expr
15463 ("non-static expression used for modular type bound!", Mod_Expr);
15464 M_Val := 2 ** System_Max_Binary_Modulus_Power;
15466 M_Val := Expr_Value (Mod_Expr);
15470 Error_Msg_N ("modulus value must be positive", Mod_Expr);
15471 M_Val := 2 ** System_Max_Binary_Modulus_Power;
15474 Set_Modulus (T, M_Val);
15476 -- Create bounds for the modular type based on the modulus given in
15477 -- the type declaration and then analyze and resolve those bounds.
15479 Set_Scalar_Range (T,
15480 Make_Range (Sloc (Mod_Expr),
15482 Make_Integer_Literal (Sloc (Mod_Expr), 0),
15484 Make_Integer_Literal (Sloc (Mod_Expr), M_Val - 1)));
15486 -- Properly analyze the literals for the range. We do this manually
15487 -- because we can't go calling Resolve, since we are resolving these
15488 -- bounds with the type, and this type is certainly not complete yet!
15490 Set_Etype (Low_Bound (Scalar_Range (T)), T);
15491 Set_Etype (High_Bound (Scalar_Range (T)), T);
15492 Set_Is_Static_Expression (Low_Bound (Scalar_Range (T)));
15493 Set_Is_Static_Expression (High_Bound (Scalar_Range (T)));
15495 -- Loop through powers of two to find number of bits required
15497 for Bits in Int range 0 .. System_Max_Binary_Modulus_Power loop
15501 if M_Val = 2 ** Bits then
15502 Set_Modular_Size (Bits);
15507 elsif M_Val < 2 ** Bits then
15508 Set_Non_Binary_Modulus (T);
15510 if Bits > System_Max_Nonbinary_Modulus_Power then
15511 Error_Msg_Uint_1 :=
15512 UI_From_Int (System_Max_Nonbinary_Modulus_Power);
15514 ("nonbinary modulus exceeds limit (2 '*'*^ - 1)", Mod_Expr);
15515 Set_Modular_Size (System_Max_Binary_Modulus_Power);
15519 -- In the non-binary case, set size as per RM 13.3(55)
15521 Set_Modular_Size (Bits);
15528 -- If we fall through, then the size exceed System.Max_Binary_Modulus
15529 -- so we just signal an error and set the maximum size.
15531 Error_Msg_Uint_1 := UI_From_Int (System_Max_Binary_Modulus_Power);
15532 Error_Msg_F ("modulus exceeds limit (2 '*'*^)", Mod_Expr);
15534 Set_Modular_Size (System_Max_Binary_Modulus_Power);
15535 Init_Alignment (T);
15537 end Modular_Type_Declaration;
15539 --------------------------
15540 -- New_Concatenation_Op --
15541 --------------------------
15543 procedure New_Concatenation_Op (Typ : Entity_Id) is
15544 Loc : constant Source_Ptr := Sloc (Typ);
15547 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id;
15548 -- Create abbreviated declaration for the formal of a predefined
15549 -- Operator 'Op' of type 'Typ'
15551 --------------------
15552 -- Make_Op_Formal --
15553 --------------------
15555 function Make_Op_Formal (Typ, Op : Entity_Id) return Entity_Id is
15556 Formal : Entity_Id;
15558 Formal := New_Internal_Entity (E_In_Parameter, Op, Loc, 'P');
15559 Set_Etype (Formal, Typ);
15560 Set_Mechanism (Formal, Default_Mechanism);
15562 end Make_Op_Formal;
15564 -- Start of processing for New_Concatenation_Op
15567 Op := Make_Defining_Operator_Symbol (Loc, Name_Op_Concat);
15569 Set_Ekind (Op, E_Operator);
15570 Set_Scope (Op, Current_Scope);
15571 Set_Etype (Op, Typ);
15572 Set_Homonym (Op, Get_Name_Entity_Id (Name_Op_Concat));
15573 Set_Is_Immediately_Visible (Op);
15574 Set_Is_Intrinsic_Subprogram (Op);
15575 Set_Has_Completion (Op);
15576 Append_Entity (Op, Current_Scope);
15578 Set_Name_Entity_Id (Name_Op_Concat, Op);
15580 Append_Entity (Make_Op_Formal (Typ, Op), Op);
15581 Append_Entity (Make_Op_Formal (Typ, Op), Op);
15582 end New_Concatenation_Op;
15584 -------------------------
15585 -- OK_For_Limited_Init --
15586 -------------------------
15588 -- ???Check all calls of this, and compare the conditions under which it's
15591 function OK_For_Limited_Init
15593 Exp : Node_Id) return Boolean
15596 return Is_CPP_Constructor_Call (Exp)
15597 or else (Ada_Version >= Ada_05
15598 and then not Debug_Flag_Dot_L
15599 and then OK_For_Limited_Init_In_05 (Typ, Exp));
15600 end OK_For_Limited_Init;
15602 -------------------------------
15603 -- OK_For_Limited_Init_In_05 --
15604 -------------------------------
15606 function OK_For_Limited_Init_In_05
15608 Exp : Node_Id) return Boolean
15611 -- An object of a limited interface type can be initialized with any
15612 -- expression of a nonlimited descendant type.
15614 if Is_Class_Wide_Type (Typ)
15615 and then Is_Limited_Interface (Typ)
15616 and then not Is_Limited_Type (Etype (Exp))
15621 -- Ada 2005 (AI-287, AI-318): Relax the strictness of the front end in
15622 -- case of limited aggregates (including extension aggregates), and
15623 -- function calls. The function call may have been give in prefixed
15624 -- notation, in which case the original node is an indexed component.
15626 case Nkind (Original_Node (Exp)) is
15627 when N_Aggregate | N_Extension_Aggregate | N_Function_Call | N_Op =>
15630 when N_Qualified_Expression =>
15632 OK_For_Limited_Init_In_05
15633 (Typ, Expression (Original_Node (Exp)));
15635 -- Ada 2005 (AI-251): If a class-wide interface object is initialized
15636 -- with a function call, the expander has rewritten the call into an
15637 -- N_Type_Conversion node to force displacement of the pointer to
15638 -- reference the component containing the secondary dispatch table.
15639 -- Otherwise a type conversion is not a legal context.
15640 -- A return statement for a build-in-place function returning a
15641 -- synchronized type also introduces an unchecked conversion.
15643 when N_Type_Conversion | N_Unchecked_Type_Conversion =>
15644 return not Comes_From_Source (Exp)
15646 OK_For_Limited_Init_In_05
15647 (Typ, Expression (Original_Node (Exp)));
15649 when N_Indexed_Component | N_Selected_Component =>
15650 return Nkind (Exp) = N_Function_Call;
15652 -- A use of 'Input is a function call, hence allowed. Normally the
15653 -- attribute will be changed to a call, but the attribute by itself
15654 -- can occur with -gnatc.
15656 when N_Attribute_Reference =>
15657 return Attribute_Name (Original_Node (Exp)) = Name_Input;
15662 end OK_For_Limited_Init_In_05;
15664 -------------------------------------------
15665 -- Ordinary_Fixed_Point_Type_Declaration --
15666 -------------------------------------------
15668 procedure Ordinary_Fixed_Point_Type_Declaration
15672 Loc : constant Source_Ptr := Sloc (Def);
15673 Delta_Expr : constant Node_Id := Delta_Expression (Def);
15674 RRS : constant Node_Id := Real_Range_Specification (Def);
15675 Implicit_Base : Entity_Id;
15682 Check_Restriction (No_Fixed_Point, Def);
15684 -- Create implicit base type
15687 Create_Itype (E_Ordinary_Fixed_Point_Type, Parent (Def), T, 'B');
15688 Set_Etype (Implicit_Base, Implicit_Base);
15690 -- Analyze and process delta expression
15692 Analyze_And_Resolve (Delta_Expr, Any_Real);
15694 Check_Delta_Expression (Delta_Expr);
15695 Delta_Val := Expr_Value_R (Delta_Expr);
15697 Set_Delta_Value (Implicit_Base, Delta_Val);
15699 -- Compute default small from given delta, which is the largest power
15700 -- of two that does not exceed the given delta value.
15710 if Delta_Val < Ureal_1 then
15711 while Delta_Val < Tmp loop
15712 Tmp := Tmp / Ureal_2;
15713 Scale := Scale + 1;
15718 Tmp := Tmp * Ureal_2;
15719 exit when Tmp > Delta_Val;
15720 Scale := Scale - 1;
15724 Small_Val := UR_From_Components (Uint_1, UI_From_Int (Scale), 2);
15727 Set_Small_Value (Implicit_Base, Small_Val);
15729 -- If no range was given, set a dummy range
15731 if RRS <= Empty_Or_Error then
15732 Low_Val := -Small_Val;
15733 High_Val := Small_Val;
15735 -- Otherwise analyze and process given range
15739 Low : constant Node_Id := Low_Bound (RRS);
15740 High : constant Node_Id := High_Bound (RRS);
15743 Analyze_And_Resolve (Low, Any_Real);
15744 Analyze_And_Resolve (High, Any_Real);
15745 Check_Real_Bound (Low);
15746 Check_Real_Bound (High);
15748 -- Obtain and set the range
15750 Low_Val := Expr_Value_R (Low);
15751 High_Val := Expr_Value_R (High);
15753 if Low_Val > High_Val then
15754 Error_Msg_NE ("?fixed point type& has null range", Def, T);
15759 -- The range for both the implicit base and the declared first subtype
15760 -- cannot be set yet, so we use the special routine Set_Fixed_Range to
15761 -- set a temporary range in place. Note that the bounds of the base
15762 -- type will be widened to be symmetrical and to fill the available
15763 -- bits when the type is frozen.
15765 -- We could do this with all discrete types, and probably should, but
15766 -- we absolutely have to do it for fixed-point, since the end-points
15767 -- of the range and the size are determined by the small value, which
15768 -- could be reset before the freeze point.
15770 Set_Fixed_Range (Implicit_Base, Loc, Low_Val, High_Val);
15771 Set_Fixed_Range (T, Loc, Low_Val, High_Val);
15773 -- Complete definition of first subtype
15775 Set_Ekind (T, E_Ordinary_Fixed_Point_Subtype);
15776 Set_Etype (T, Implicit_Base);
15777 Init_Size_Align (T);
15778 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
15779 Set_Small_Value (T, Small_Val);
15780 Set_Delta_Value (T, Delta_Val);
15781 Set_Is_Constrained (T);
15783 end Ordinary_Fixed_Point_Type_Declaration;
15785 ----------------------------------------
15786 -- Prepare_Private_Subtype_Completion --
15787 ----------------------------------------
15789 procedure Prepare_Private_Subtype_Completion
15791 Related_Nod : Node_Id)
15793 Id_B : constant Entity_Id := Base_Type (Id);
15794 Full_B : constant Entity_Id := Full_View (Id_B);
15798 if Present (Full_B) then
15800 -- The Base_Type is already completed, we can complete the subtype
15801 -- now. We have to create a new entity with the same name, Thus we
15802 -- can't use Create_Itype.
15804 -- This is messy, should be fixed ???
15806 Full := Make_Defining_Identifier (Sloc (Id), Chars (Id));
15807 Set_Is_Itype (Full);
15808 Set_Associated_Node_For_Itype (Full, Related_Nod);
15809 Complete_Private_Subtype (Id, Full, Full_B, Related_Nod);
15812 -- The parent subtype may be private, but the base might not, in some
15813 -- nested instances. In that case, the subtype does not need to be
15814 -- exchanged. It would still be nice to make private subtypes and their
15815 -- bases consistent at all times ???
15817 if Is_Private_Type (Id_B) then
15818 Append_Elmt (Id, Private_Dependents (Id_B));
15821 end Prepare_Private_Subtype_Completion;
15823 ---------------------------
15824 -- Process_Discriminants --
15825 ---------------------------
15827 procedure Process_Discriminants
15829 Prev : Entity_Id := Empty)
15831 Elist : constant Elist_Id := New_Elmt_List;
15834 Discr_Number : Uint;
15835 Discr_Type : Entity_Id;
15836 Default_Present : Boolean := False;
15837 Default_Not_Present : Boolean := False;
15840 -- A composite type other than an array type can have discriminants.
15841 -- On entry, the current scope is the composite type.
15843 -- The discriminants are initially entered into the scope of the type
15844 -- via Enter_Name with the default Ekind of E_Void to prevent premature
15845 -- use, as explained at the end of this procedure.
15847 Discr := First (Discriminant_Specifications (N));
15848 while Present (Discr) loop
15849 Enter_Name (Defining_Identifier (Discr));
15851 -- For navigation purposes we add a reference to the discriminant
15852 -- in the entity for the type. If the current declaration is a
15853 -- completion, place references on the partial view. Otherwise the
15854 -- type is the current scope.
15856 if Present (Prev) then
15858 -- The references go on the partial view, if present. If the
15859 -- partial view has discriminants, the references have been
15860 -- generated already.
15862 if not Has_Discriminants (Prev) then
15863 Generate_Reference (Prev, Defining_Identifier (Discr), 'd');
15867 (Current_Scope, Defining_Identifier (Discr), 'd');
15870 if Nkind (Discriminant_Type (Discr)) = N_Access_Definition then
15871 Discr_Type := Access_Definition (Discr, Discriminant_Type (Discr));
15873 -- Ada 2005 (AI-254)
15875 if Present (Access_To_Subprogram_Definition
15876 (Discriminant_Type (Discr)))
15877 and then Protected_Present (Access_To_Subprogram_Definition
15878 (Discriminant_Type (Discr)))
15881 Replace_Anonymous_Access_To_Protected_Subprogram (Discr);
15885 Find_Type (Discriminant_Type (Discr));
15886 Discr_Type := Etype (Discriminant_Type (Discr));
15888 if Error_Posted (Discriminant_Type (Discr)) then
15889 Discr_Type := Any_Type;
15893 if Is_Access_Type (Discr_Type) then
15895 -- Ada 2005 (AI-230): Access discriminant allowed in non-limited
15898 if Ada_Version < Ada_05 then
15899 Check_Access_Discriminant_Requires_Limited
15900 (Discr, Discriminant_Type (Discr));
15903 if Ada_Version = Ada_83 and then Comes_From_Source (Discr) then
15905 ("(Ada 83) access discriminant not allowed", Discr);
15908 elsif not Is_Discrete_Type (Discr_Type) then
15909 Error_Msg_N ("discriminants must have a discrete or access type",
15910 Discriminant_Type (Discr));
15913 Set_Etype (Defining_Identifier (Discr), Discr_Type);
15915 -- If a discriminant specification includes the assignment compound
15916 -- delimiter followed by an expression, the expression is the default
15917 -- expression of the discriminant; the default expression must be of
15918 -- the type of the discriminant. (RM 3.7.1) Since this expression is
15919 -- a default expression, we do the special preanalysis, since this
15920 -- expression does not freeze (see "Handling of Default and Per-
15921 -- Object Expressions" in spec of package Sem).
15923 if Present (Expression (Discr)) then
15924 Preanalyze_Spec_Expression (Expression (Discr), Discr_Type);
15926 if Nkind (N) = N_Formal_Type_Declaration then
15928 ("discriminant defaults not allowed for formal type",
15929 Expression (Discr));
15931 -- Tagged types cannot have defaulted discriminants, but a
15932 -- non-tagged private type with defaulted discriminants
15933 -- can have a tagged completion.
15935 elsif Is_Tagged_Type (Current_Scope)
15936 and then Comes_From_Source (N)
15939 ("discriminants of tagged type cannot have defaults",
15940 Expression (Discr));
15943 Default_Present := True;
15944 Append_Elmt (Expression (Discr), Elist);
15946 -- Tag the defining identifiers for the discriminants with
15947 -- their corresponding default expressions from the tree.
15949 Set_Discriminant_Default_Value
15950 (Defining_Identifier (Discr), Expression (Discr));
15954 Default_Not_Present := True;
15957 -- Ada 2005 (AI-231): Create an Itype that is a duplicate of
15958 -- Discr_Type but with the null-exclusion attribute
15960 if Ada_Version >= Ada_05 then
15962 -- Ada 2005 (AI-231): Static checks
15964 if Can_Never_Be_Null (Discr_Type) then
15965 Null_Exclusion_Static_Checks (Discr);
15967 elsif Is_Access_Type (Discr_Type)
15968 and then Null_Exclusion_Present (Discr)
15970 -- No need to check itypes because in their case this check
15971 -- was done at their point of creation
15973 and then not Is_Itype (Discr_Type)
15975 if Can_Never_Be_Null (Discr_Type) then
15977 ("`NOT NULL` not allowed (& already excludes null)",
15982 Set_Etype (Defining_Identifier (Discr),
15983 Create_Null_Excluding_Itype
15985 Related_Nod => Discr));
15987 -- Check for improper null exclusion if the type is otherwise
15988 -- legal for a discriminant.
15990 elsif Null_Exclusion_Present (Discr)
15991 and then Is_Discrete_Type (Discr_Type)
15994 ("null exclusion can only apply to an access type", Discr);
15997 -- Ada 2005 (AI-402): access discriminants of nonlimited types
15998 -- can't have defaults. Synchronized types, or types that are
15999 -- explicitly limited are fine, but special tests apply to derived
16000 -- types in generics: in a generic body we have to assume the
16001 -- worst, and therefore defaults are not allowed if the parent is
16002 -- a generic formal private type (see ACATS B370001).
16004 if Is_Access_Type (Discr_Type) then
16005 if Ekind (Discr_Type) /= E_Anonymous_Access_Type
16006 or else not Default_Present
16007 or else Is_Limited_Record (Current_Scope)
16008 or else Is_Concurrent_Type (Current_Scope)
16009 or else Is_Concurrent_Record_Type (Current_Scope)
16010 or else Ekind (Current_Scope) = E_Limited_Private_Type
16012 if not Is_Derived_Type (Current_Scope)
16013 or else not Is_Generic_Type (Etype (Current_Scope))
16014 or else not In_Package_Body (Scope (Etype (Current_Scope)))
16015 or else Limited_Present
16016 (Type_Definition (Parent (Current_Scope)))
16021 Error_Msg_N ("access discriminants of nonlimited types",
16022 Expression (Discr));
16023 Error_Msg_N ("\cannot have defaults", Expression (Discr));
16026 elsif Present (Expression (Discr)) then
16028 ("(Ada 2005) access discriminants of nonlimited types",
16029 Expression (Discr));
16030 Error_Msg_N ("\cannot have defaults", Expression (Discr));
16038 -- An element list consisting of the default expressions of the
16039 -- discriminants is constructed in the above loop and used to set
16040 -- the Discriminant_Constraint attribute for the type. If an object
16041 -- is declared of this (record or task) type without any explicit
16042 -- discriminant constraint given, this element list will form the
16043 -- actual parameters for the corresponding initialization procedure
16046 Set_Discriminant_Constraint (Current_Scope, Elist);
16047 Set_Stored_Constraint (Current_Scope, No_Elist);
16049 -- Default expressions must be provided either for all or for none
16050 -- of the discriminants of a discriminant part. (RM 3.7.1)
16052 if Default_Present and then Default_Not_Present then
16054 ("incomplete specification of defaults for discriminants", N);
16057 -- The use of the name of a discriminant is not allowed in default
16058 -- expressions of a discriminant part if the specification of the
16059 -- discriminant is itself given in the discriminant part. (RM 3.7.1)
16061 -- To detect this, the discriminant names are entered initially with an
16062 -- Ekind of E_Void (which is the default Ekind given by Enter_Name). Any
16063 -- attempt to use a void entity (for example in an expression that is
16064 -- type-checked) produces the error message: premature usage. Now after
16065 -- completing the semantic analysis of the discriminant part, we can set
16066 -- the Ekind of all the discriminants appropriately.
16068 Discr := First (Discriminant_Specifications (N));
16069 Discr_Number := Uint_1;
16070 while Present (Discr) loop
16071 Id := Defining_Identifier (Discr);
16072 Set_Ekind (Id, E_Discriminant);
16073 Init_Component_Location (Id);
16075 Set_Discriminant_Number (Id, Discr_Number);
16077 -- Make sure this is always set, even in illegal programs
16079 Set_Corresponding_Discriminant (Id, Empty);
16081 -- Initialize the Original_Record_Component to the entity itself.
16082 -- Inherit_Components will propagate the right value to
16083 -- discriminants in derived record types.
16085 Set_Original_Record_Component (Id, Id);
16087 -- Create the discriminal for the discriminant
16089 Build_Discriminal (Id);
16092 Discr_Number := Discr_Number + 1;
16095 Set_Has_Discriminants (Current_Scope);
16096 end Process_Discriminants;
16098 -----------------------
16099 -- Process_Full_View --
16100 -----------------------
16102 procedure Process_Full_View (N : Node_Id; Full_T, Priv_T : Entity_Id) is
16103 Priv_Parent : Entity_Id;
16104 Full_Parent : Entity_Id;
16105 Full_Indic : Node_Id;
16107 procedure Collect_Implemented_Interfaces
16109 Ifaces : Elist_Id);
16110 -- Ada 2005: Gather all the interfaces that Typ directly or
16111 -- inherently implements. Duplicate entries are not added to
16112 -- the list Ifaces.
16114 ------------------------------------
16115 -- Collect_Implemented_Interfaces --
16116 ------------------------------------
16118 procedure Collect_Implemented_Interfaces
16123 Iface_Elmt : Elmt_Id;
16126 -- Abstract interfaces are only associated with tagged record types
16128 if not Is_Tagged_Type (Typ)
16129 or else not Is_Record_Type (Typ)
16134 -- Recursively climb to the ancestors
16136 if Etype (Typ) /= Typ
16138 -- Protect the frontend against wrong cyclic declarations like:
16140 -- type B is new A with private;
16141 -- type C is new A with private;
16143 -- type B is new C with null record;
16144 -- type C is new B with null record;
16146 and then Etype (Typ) /= Priv_T
16147 and then Etype (Typ) /= Full_T
16149 -- Keep separate the management of private type declarations
16151 if Ekind (Typ) = E_Record_Type_With_Private then
16153 -- Handle the following erronous case:
16154 -- type Private_Type is tagged private;
16156 -- type Private_Type is new Type_Implementing_Iface;
16158 if Present (Full_View (Typ))
16159 and then Etype (Typ) /= Full_View (Typ)
16161 if Is_Interface (Etype (Typ)) then
16162 Append_Unique_Elmt (Etype (Typ), Ifaces);
16165 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
16168 -- Non-private types
16171 if Is_Interface (Etype (Typ)) then
16172 Append_Unique_Elmt (Etype (Typ), Ifaces);
16175 Collect_Implemented_Interfaces (Etype (Typ), Ifaces);
16179 -- Handle entities in the list of abstract interfaces
16181 if Present (Interfaces (Typ)) then
16182 Iface_Elmt := First_Elmt (Interfaces (Typ));
16183 while Present (Iface_Elmt) loop
16184 Iface := Node (Iface_Elmt);
16186 pragma Assert (Is_Interface (Iface));
16188 if not Contain_Interface (Iface, Ifaces) then
16189 Append_Elmt (Iface, Ifaces);
16190 Collect_Implemented_Interfaces (Iface, Ifaces);
16193 Next_Elmt (Iface_Elmt);
16196 end Collect_Implemented_Interfaces;
16198 -- Start of processing for Process_Full_View
16201 -- First some sanity checks that must be done after semantic
16202 -- decoration of the full view and thus cannot be placed with other
16203 -- similar checks in Find_Type_Name
16205 if not Is_Limited_Type (Priv_T)
16206 and then (Is_Limited_Type (Full_T)
16207 or else Is_Limited_Composite (Full_T))
16210 ("completion of nonlimited type cannot be limited", Full_T);
16211 Explain_Limited_Type (Full_T, Full_T);
16213 elsif Is_Abstract_Type (Full_T)
16214 and then not Is_Abstract_Type (Priv_T)
16217 ("completion of nonabstract type cannot be abstract", Full_T);
16219 elsif Is_Tagged_Type (Priv_T)
16220 and then Is_Limited_Type (Priv_T)
16221 and then not Is_Limited_Type (Full_T)
16223 -- If pragma CPP_Class was applied to the private declaration
16224 -- propagate the limitedness to the full-view
16226 if Is_CPP_Class (Priv_T) then
16227 Set_Is_Limited_Record (Full_T);
16229 -- GNAT allow its own definition of Limited_Controlled to disobey
16230 -- this rule in order in ease the implementation. The next test is
16231 -- safe because Root_Controlled is defined in a private system child
16233 elsif Etype (Full_T) = Full_View (RTE (RE_Root_Controlled)) then
16234 Set_Is_Limited_Composite (Full_T);
16237 ("completion of limited tagged type must be limited", Full_T);
16240 elsif Is_Generic_Type (Priv_T) then
16241 Error_Msg_N ("generic type cannot have a completion", Full_T);
16244 -- Check that ancestor interfaces of private and full views are
16245 -- consistent. We omit this check for synchronized types because
16246 -- they are performed on the corresponding record type when frozen.
16248 if Ada_Version >= Ada_05
16249 and then Is_Tagged_Type (Priv_T)
16250 and then Is_Tagged_Type (Full_T)
16251 and then not Is_Concurrent_Type (Full_T)
16255 Priv_T_Ifaces : constant Elist_Id := New_Elmt_List;
16256 Full_T_Ifaces : constant Elist_Id := New_Elmt_List;
16259 Collect_Implemented_Interfaces (Priv_T, Priv_T_Ifaces);
16260 Collect_Implemented_Interfaces (Full_T, Full_T_Ifaces);
16262 -- Ada 2005 (AI-251): The partial view shall be a descendant of
16263 -- an interface type if and only if the full type is descendant
16264 -- of the interface type (AARM 7.3 (7.3/2).
16266 Iface := Find_Hidden_Interface (Priv_T_Ifaces, Full_T_Ifaces);
16268 if Present (Iface) then
16269 Error_Msg_NE ("interface & not implemented by full type " &
16270 "(RM-2005 7.3 (7.3/2))", Priv_T, Iface);
16273 Iface := Find_Hidden_Interface (Full_T_Ifaces, Priv_T_Ifaces);
16275 if Present (Iface) then
16276 Error_Msg_NE ("interface & not implemented by partial view " &
16277 "(RM-2005 7.3 (7.3/2))", Full_T, Iface);
16282 if Is_Tagged_Type (Priv_T)
16283 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
16284 and then Is_Derived_Type (Full_T)
16286 Priv_Parent := Etype (Priv_T);
16288 -- The full view of a private extension may have been transformed
16289 -- into an unconstrained derived type declaration and a subtype
16290 -- declaration (see build_derived_record_type for details).
16292 if Nkind (N) = N_Subtype_Declaration then
16293 Full_Indic := Subtype_Indication (N);
16294 Full_Parent := Etype (Base_Type (Full_T));
16296 Full_Indic := Subtype_Indication (Type_Definition (N));
16297 Full_Parent := Etype (Full_T);
16300 -- Check that the parent type of the full type is a descendant of
16301 -- the ancestor subtype given in the private extension. If either
16302 -- entity has an Etype equal to Any_Type then we had some previous
16303 -- error situation [7.3(8)].
16305 if Priv_Parent = Any_Type or else Full_Parent = Any_Type then
16308 -- Ada 2005 (AI-251): Interfaces in the full-typ can be given in
16309 -- any order. Therefore we don't have to check that its parent must
16310 -- be a descendant of the parent of the private type declaration.
16312 elsif Is_Interface (Priv_Parent)
16313 and then Is_Interface (Full_Parent)
16317 -- Ada 2005 (AI-251): If the parent of the private type declaration
16318 -- is an interface there is no need to check that it is an ancestor
16319 -- of the associated full type declaration. The required tests for
16320 -- this case are performed by Build_Derived_Record_Type.
16322 elsif not Is_Interface (Base_Type (Priv_Parent))
16323 and then not Is_Ancestor (Base_Type (Priv_Parent), Full_Parent)
16326 ("parent of full type must descend from parent"
16327 & " of private extension", Full_Indic);
16329 -- Check the rules of 7.3(10): if the private extension inherits
16330 -- known discriminants, then the full type must also inherit those
16331 -- discriminants from the same (ancestor) type, and the parent
16332 -- subtype of the full type must be constrained if and only if
16333 -- the ancestor subtype of the private extension is constrained.
16335 elsif No (Discriminant_Specifications (Parent (Priv_T)))
16336 and then not Has_Unknown_Discriminants (Priv_T)
16337 and then Has_Discriminants (Base_Type (Priv_Parent))
16340 Priv_Indic : constant Node_Id :=
16341 Subtype_Indication (Parent (Priv_T));
16343 Priv_Constr : constant Boolean :=
16344 Is_Constrained (Priv_Parent)
16346 Nkind (Priv_Indic) = N_Subtype_Indication
16347 or else Is_Constrained (Entity (Priv_Indic));
16349 Full_Constr : constant Boolean :=
16350 Is_Constrained (Full_Parent)
16352 Nkind (Full_Indic) = N_Subtype_Indication
16353 or else Is_Constrained (Entity (Full_Indic));
16355 Priv_Discr : Entity_Id;
16356 Full_Discr : Entity_Id;
16359 Priv_Discr := First_Discriminant (Priv_Parent);
16360 Full_Discr := First_Discriminant (Full_Parent);
16361 while Present (Priv_Discr) and then Present (Full_Discr) loop
16362 if Original_Record_Component (Priv_Discr) =
16363 Original_Record_Component (Full_Discr)
16365 Corresponding_Discriminant (Priv_Discr) =
16366 Corresponding_Discriminant (Full_Discr)
16373 Next_Discriminant (Priv_Discr);
16374 Next_Discriminant (Full_Discr);
16377 if Present (Priv_Discr) or else Present (Full_Discr) then
16379 ("full view must inherit discriminants of the parent type"
16380 & " used in the private extension", Full_Indic);
16382 elsif Priv_Constr and then not Full_Constr then
16384 ("parent subtype of full type must be constrained",
16387 elsif Full_Constr and then not Priv_Constr then
16389 ("parent subtype of full type must be unconstrained",
16394 -- Check the rules of 7.3(12): if a partial view has neither known
16395 -- or unknown discriminants, then the full type declaration shall
16396 -- define a definite subtype.
16398 elsif not Has_Unknown_Discriminants (Priv_T)
16399 and then not Has_Discriminants (Priv_T)
16400 and then not Is_Constrained (Full_T)
16403 ("full view must define a constrained type if partial view"
16404 & " has no discriminants", Full_T);
16407 -- ??????? Do we implement the following properly ?????
16408 -- If the ancestor subtype of a private extension has constrained
16409 -- discriminants, then the parent subtype of the full view shall
16410 -- impose a statically matching constraint on those discriminants
16414 -- For untagged types, verify that a type without discriminants
16415 -- is not completed with an unconstrained type.
16417 if not Is_Indefinite_Subtype (Priv_T)
16418 and then Is_Indefinite_Subtype (Full_T)
16420 Error_Msg_N ("full view of type must be definite subtype", Full_T);
16424 -- AI-419: verify that the use of "limited" is consistent
16427 Orig_Decl : constant Node_Id := Original_Node (N);
16430 if Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
16431 and then not Limited_Present (Parent (Priv_T))
16432 and then not Synchronized_Present (Parent (Priv_T))
16433 and then Nkind (Orig_Decl) = N_Full_Type_Declaration
16435 (Type_Definition (Orig_Decl)) = N_Derived_Type_Definition
16436 and then Limited_Present (Type_Definition (Orig_Decl))
16439 ("full view of non-limited extension cannot be limited", N);
16443 -- Ada 2005 (AI-443): A synchronized private extension must be
16444 -- completed by a task or protected type.
16446 if Ada_Version >= Ada_05
16447 and then Nkind (Parent (Priv_T)) = N_Private_Extension_Declaration
16448 and then Synchronized_Present (Parent (Priv_T))
16449 and then not Is_Concurrent_Type (Full_T)
16451 Error_Msg_N ("full view of synchronized extension must " &
16452 "be synchronized type", N);
16455 -- Ada 2005 AI-363: if the full view has discriminants with
16456 -- defaults, it is illegal to declare constrained access subtypes
16457 -- whose designated type is the current type. This allows objects
16458 -- of the type that are declared in the heap to be unconstrained.
16460 if not Has_Unknown_Discriminants (Priv_T)
16461 and then not Has_Discriminants (Priv_T)
16462 and then Has_Discriminants (Full_T)
16464 Present (Discriminant_Default_Value (First_Discriminant (Full_T)))
16466 Set_Has_Constrained_Partial_View (Full_T);
16467 Set_Has_Constrained_Partial_View (Priv_T);
16470 -- Create a full declaration for all its subtypes recorded in
16471 -- Private_Dependents and swap them similarly to the base type. These
16472 -- are subtypes that have been define before the full declaration of
16473 -- the private type. We also swap the entry in Private_Dependents list
16474 -- so we can properly restore the private view on exit from the scope.
16477 Priv_Elmt : Elmt_Id;
16482 Priv_Elmt := First_Elmt (Private_Dependents (Priv_T));
16483 while Present (Priv_Elmt) loop
16484 Priv := Node (Priv_Elmt);
16486 if Ekind_In (Priv, E_Private_Subtype,
16487 E_Limited_Private_Subtype,
16488 E_Record_Subtype_With_Private)
16490 Full := Make_Defining_Identifier (Sloc (Priv), Chars (Priv));
16491 Set_Is_Itype (Full);
16492 Set_Parent (Full, Parent (Priv));
16493 Set_Associated_Node_For_Itype (Full, N);
16495 -- Now we need to complete the private subtype, but since the
16496 -- base type has already been swapped, we must also swap the
16497 -- subtypes (and thus, reverse the arguments in the call to
16498 -- Complete_Private_Subtype).
16500 Copy_And_Swap (Priv, Full);
16501 Complete_Private_Subtype (Full, Priv, Full_T, N);
16502 Replace_Elmt (Priv_Elmt, Full);
16505 Next_Elmt (Priv_Elmt);
16509 -- If the private view was tagged, copy the new primitive operations
16510 -- from the private view to the full view.
16512 if Is_Tagged_Type (Full_T) then
16514 Disp_Typ : Entity_Id;
16515 Full_List : Elist_Id;
16517 Prim_Elmt : Elmt_Id;
16518 Priv_List : Elist_Id;
16522 L : Elist_Id) return Boolean;
16523 -- Determine whether list L contains element E
16531 L : Elist_Id) return Boolean
16533 List_Elmt : Elmt_Id;
16536 List_Elmt := First_Elmt (L);
16537 while Present (List_Elmt) loop
16538 if Node (List_Elmt) = E then
16542 Next_Elmt (List_Elmt);
16548 -- Start of processing
16551 if Is_Tagged_Type (Priv_T) then
16552 Priv_List := Primitive_Operations (Priv_T);
16553 Prim_Elmt := First_Elmt (Priv_List);
16555 -- In the case of a concurrent type completing a private tagged
16556 -- type, primitives may have been declared in between the two
16557 -- views. These subprograms need to be wrapped the same way
16558 -- entries and protected procedures are handled because they
16559 -- cannot be directly shared by the two views.
16561 if Is_Concurrent_Type (Full_T) then
16563 Conc_Typ : constant Entity_Id :=
16564 Corresponding_Record_Type (Full_T);
16565 Curr_Nod : Node_Id := Parent (Conc_Typ);
16566 Wrap_Spec : Node_Id;
16569 while Present (Prim_Elmt) loop
16570 Prim := Node (Prim_Elmt);
16572 if Comes_From_Source (Prim)
16573 and then not Is_Abstract_Subprogram (Prim)
16576 Make_Subprogram_Declaration (Sloc (Prim),
16580 Obj_Typ => Conc_Typ,
16582 Parameter_Specifications (
16585 Insert_After (Curr_Nod, Wrap_Spec);
16586 Curr_Nod := Wrap_Spec;
16588 Analyze (Wrap_Spec);
16591 Next_Elmt (Prim_Elmt);
16597 -- For non-concurrent types, transfer explicit primitives, but
16598 -- omit those inherited from the parent of the private view
16599 -- since they will be re-inherited later on.
16602 Full_List := Primitive_Operations (Full_T);
16604 while Present (Prim_Elmt) loop
16605 Prim := Node (Prim_Elmt);
16607 if Comes_From_Source (Prim)
16608 and then not Contains (Prim, Full_List)
16610 Append_Elmt (Prim, Full_List);
16613 Next_Elmt (Prim_Elmt);
16617 -- Untagged private view
16620 Full_List := Primitive_Operations (Full_T);
16622 -- In this case the partial view is untagged, so here we locate
16623 -- all of the earlier primitives that need to be treated as
16624 -- dispatching (those that appear between the two views). Note
16625 -- that these additional operations must all be new operations
16626 -- (any earlier operations that override inherited operations
16627 -- of the full view will already have been inserted in the
16628 -- primitives list, marked by Check_Operation_From_Private_View
16629 -- as dispatching. Note that implicit "/=" operators are
16630 -- excluded from being added to the primitives list since they
16631 -- shouldn't be treated as dispatching (tagged "/=" is handled
16634 Prim := Next_Entity (Full_T);
16635 while Present (Prim) and then Prim /= Priv_T loop
16636 if Ekind_In (Prim, E_Procedure, E_Function) then
16637 Disp_Typ := Find_Dispatching_Type (Prim);
16639 if Disp_Typ = Full_T
16640 and then (Chars (Prim) /= Name_Op_Ne
16641 or else Comes_From_Source (Prim))
16643 Check_Controlling_Formals (Full_T, Prim);
16645 if not Is_Dispatching_Operation (Prim) then
16646 Append_Elmt (Prim, Full_List);
16647 Set_Is_Dispatching_Operation (Prim, True);
16648 Set_DT_Position (Prim, No_Uint);
16651 elsif Is_Dispatching_Operation (Prim)
16652 and then Disp_Typ /= Full_T
16655 -- Verify that it is not otherwise controlled by a
16656 -- formal or a return value of type T.
16658 Check_Controlling_Formals (Disp_Typ, Prim);
16662 Next_Entity (Prim);
16666 -- For the tagged case, the two views can share the same
16667 -- Primitive Operation list and the same class wide type.
16668 -- Update attributes of the class-wide type which depend on
16669 -- the full declaration.
16671 if Is_Tagged_Type (Priv_T) then
16672 Set_Primitive_Operations (Priv_T, Full_List);
16673 Set_Class_Wide_Type
16674 (Base_Type (Full_T), Class_Wide_Type (Priv_T));
16676 Set_Has_Task (Class_Wide_Type (Priv_T), Has_Task (Full_T));
16681 -- Ada 2005 AI 161: Check preelaboratable initialization consistency
16683 if Known_To_Have_Preelab_Init (Priv_T) then
16685 -- Case where there is a pragma Preelaborable_Initialization. We
16686 -- always allow this in predefined units, which is a bit of a kludge,
16687 -- but it means we don't have to struggle to meet the requirements in
16688 -- the RM for having Preelaborable Initialization. Otherwise we
16689 -- require that the type meets the RM rules. But we can't check that
16690 -- yet, because of the rule about overriding Ininitialize, so we
16691 -- simply set a flag that will be checked at freeze time.
16693 if not In_Predefined_Unit (Full_T) then
16694 Set_Must_Have_Preelab_Init (Full_T);
16698 -- If pragma CPP_Class was applied to the private type declaration,
16699 -- propagate it now to the full type declaration.
16701 if Is_CPP_Class (Priv_T) then
16702 Set_Is_CPP_Class (Full_T);
16703 Set_Convention (Full_T, Convention_CPP);
16706 -- If the private view has user specified stream attributes, then so has
16709 if Has_Specified_Stream_Read (Priv_T) then
16710 Set_Has_Specified_Stream_Read (Full_T);
16712 if Has_Specified_Stream_Write (Priv_T) then
16713 Set_Has_Specified_Stream_Write (Full_T);
16715 if Has_Specified_Stream_Input (Priv_T) then
16716 Set_Has_Specified_Stream_Input (Full_T);
16718 if Has_Specified_Stream_Output (Priv_T) then
16719 Set_Has_Specified_Stream_Output (Full_T);
16721 end Process_Full_View;
16723 -----------------------------------
16724 -- Process_Incomplete_Dependents --
16725 -----------------------------------
16727 procedure Process_Incomplete_Dependents
16729 Full_T : Entity_Id;
16732 Inc_Elmt : Elmt_Id;
16733 Priv_Dep : Entity_Id;
16734 New_Subt : Entity_Id;
16736 Disc_Constraint : Elist_Id;
16739 if No (Private_Dependents (Inc_T)) then
16743 -- Itypes that may be generated by the completion of an incomplete
16744 -- subtype are not used by the back-end and not attached to the tree.
16745 -- They are created only for constraint-checking purposes.
16747 Inc_Elmt := First_Elmt (Private_Dependents (Inc_T));
16748 while Present (Inc_Elmt) loop
16749 Priv_Dep := Node (Inc_Elmt);
16751 if Ekind (Priv_Dep) = E_Subprogram_Type then
16753 -- An Access_To_Subprogram type may have a return type or a
16754 -- parameter type that is incomplete. Replace with the full view.
16756 if Etype (Priv_Dep) = Inc_T then
16757 Set_Etype (Priv_Dep, Full_T);
16761 Formal : Entity_Id;
16764 Formal := First_Formal (Priv_Dep);
16765 while Present (Formal) loop
16766 if Etype (Formal) = Inc_T then
16767 Set_Etype (Formal, Full_T);
16770 Next_Formal (Formal);
16774 elsif Is_Overloadable (Priv_Dep) then
16776 -- A protected operation is never dispatching: only its
16777 -- wrapper operation (which has convention Ada) is.
16779 if Is_Tagged_Type (Full_T)
16780 and then Convention (Priv_Dep) /= Convention_Protected
16783 -- Subprogram has an access parameter whose designated type
16784 -- was incomplete. Reexamine declaration now, because it may
16785 -- be a primitive operation of the full type.
16787 Check_Operation_From_Incomplete_Type (Priv_Dep, Inc_T);
16788 Set_Is_Dispatching_Operation (Priv_Dep);
16789 Check_Controlling_Formals (Full_T, Priv_Dep);
16792 elsif Ekind (Priv_Dep) = E_Subprogram_Body then
16794 -- Can happen during processing of a body before the completion
16795 -- of a TA type. Ignore, because spec is also on dependent list.
16799 -- Ada 2005 (AI-412): Transform a regular incomplete subtype into a
16800 -- corresponding subtype of the full view.
16802 elsif Ekind (Priv_Dep) = E_Incomplete_Subtype then
16803 Set_Subtype_Indication
16804 (Parent (Priv_Dep), New_Reference_To (Full_T, Sloc (Priv_Dep)));
16805 Set_Etype (Priv_Dep, Full_T);
16806 Set_Ekind (Priv_Dep, Subtype_Kind (Ekind (Full_T)));
16807 Set_Analyzed (Parent (Priv_Dep), False);
16809 -- Reanalyze the declaration, suppressing the call to
16810 -- Enter_Name to avoid duplicate names.
16812 Analyze_Subtype_Declaration
16813 (N => Parent (Priv_Dep),
16816 -- Dependent is a subtype
16819 -- We build a new subtype indication using the full view of the
16820 -- incomplete parent. The discriminant constraints have been
16821 -- elaborated already at the point of the subtype declaration.
16823 New_Subt := Create_Itype (E_Void, N);
16825 if Has_Discriminants (Full_T) then
16826 Disc_Constraint := Discriminant_Constraint (Priv_Dep);
16828 Disc_Constraint := No_Elist;
16831 Build_Discriminated_Subtype (Full_T, New_Subt, Disc_Constraint, N);
16832 Set_Full_View (Priv_Dep, New_Subt);
16835 Next_Elmt (Inc_Elmt);
16837 end Process_Incomplete_Dependents;
16839 --------------------------------
16840 -- Process_Range_Expr_In_Decl --
16841 --------------------------------
16843 procedure Process_Range_Expr_In_Decl
16846 Check_List : List_Id := Empty_List;
16847 R_Check_Off : Boolean := False)
16850 R_Checks : Check_Result;
16851 Type_Decl : Node_Id;
16852 Def_Id : Entity_Id;
16855 Analyze_And_Resolve (R, Base_Type (T));
16857 if Nkind (R) = N_Range then
16858 Lo := Low_Bound (R);
16859 Hi := High_Bound (R);
16861 -- We need to ensure validity of the bounds here, because if we
16862 -- go ahead and do the expansion, then the expanded code will get
16863 -- analyzed with range checks suppressed and we miss the check.
16865 Validity_Check_Range (R);
16867 -- If there were errors in the declaration, try and patch up some
16868 -- common mistakes in the bounds. The cases handled are literals
16869 -- which are Integer where the expected type is Real and vice versa.
16870 -- These corrections allow the compilation process to proceed further
16871 -- along since some basic assumptions of the format of the bounds
16874 if Etype (R) = Any_Type then
16876 if Nkind (Lo) = N_Integer_Literal and then Is_Real_Type (T) then
16878 Make_Real_Literal (Sloc (Lo), UR_From_Uint (Intval (Lo))));
16880 elsif Nkind (Hi) = N_Integer_Literal and then Is_Real_Type (T) then
16882 Make_Real_Literal (Sloc (Hi), UR_From_Uint (Intval (Hi))));
16884 elsif Nkind (Lo) = N_Real_Literal and then Is_Integer_Type (T) then
16886 Make_Integer_Literal (Sloc (Lo), UR_To_Uint (Realval (Lo))));
16888 elsif Nkind (Hi) = N_Real_Literal and then Is_Integer_Type (T) then
16890 Make_Integer_Literal (Sloc (Hi), UR_To_Uint (Realval (Hi))));
16897 -- If the bounds of the range have been mistakenly given as string
16898 -- literals (perhaps in place of character literals), then an error
16899 -- has already been reported, but we rewrite the string literal as a
16900 -- bound of the range's type to avoid blowups in later processing
16901 -- that looks at static values.
16903 if Nkind (Lo) = N_String_Literal then
16905 Make_Attribute_Reference (Sloc (Lo),
16906 Attribute_Name => Name_First,
16907 Prefix => New_Reference_To (T, Sloc (Lo))));
16908 Analyze_And_Resolve (Lo);
16911 if Nkind (Hi) = N_String_Literal then
16913 Make_Attribute_Reference (Sloc (Hi),
16914 Attribute_Name => Name_First,
16915 Prefix => New_Reference_To (T, Sloc (Hi))));
16916 Analyze_And_Resolve (Hi);
16919 -- If bounds aren't scalar at this point then exit, avoiding
16920 -- problems with further processing of the range in this procedure.
16922 if not Is_Scalar_Type (Etype (Lo)) then
16926 -- Resolve (actually Sem_Eval) has checked that the bounds are in
16927 -- then range of the base type. Here we check whether the bounds
16928 -- are in the range of the subtype itself. Note that if the bounds
16929 -- represent the null range the Constraint_Error exception should
16932 -- ??? The following code should be cleaned up as follows
16934 -- 1. The Is_Null_Range (Lo, Hi) test should disappear since it
16935 -- is done in the call to Range_Check (R, T); below
16937 -- 2. The use of R_Check_Off should be investigated and possibly
16938 -- removed, this would clean up things a bit.
16940 if Is_Null_Range (Lo, Hi) then
16944 -- Capture values of bounds and generate temporaries for them
16945 -- if needed, before applying checks, since checks may cause
16946 -- duplication of the expression without forcing evaluation.
16948 if Expander_Active then
16949 Force_Evaluation (Lo);
16950 Force_Evaluation (Hi);
16953 -- We use a flag here instead of suppressing checks on the
16954 -- type because the type we check against isn't necessarily
16955 -- the place where we put the check.
16957 if not R_Check_Off then
16958 R_Checks := Get_Range_Checks (R, T);
16960 -- Look up tree to find an appropriate insertion point.
16961 -- This seems really junk code, and very brittle, couldn't
16962 -- we just use an insert actions call of some kind ???
16964 Type_Decl := Parent (R);
16965 while Present (Type_Decl) and then not
16966 (Nkind_In (Type_Decl, N_Full_Type_Declaration,
16967 N_Subtype_Declaration,
16969 N_Task_Type_Declaration)
16971 Nkind_In (Type_Decl, N_Single_Task_Declaration,
16972 N_Protected_Type_Declaration,
16973 N_Single_Protected_Declaration))
16975 Type_Decl := Parent (Type_Decl);
16978 -- Why would Type_Decl not be present??? Without this test,
16979 -- short regression tests fail.
16981 if Present (Type_Decl) then
16983 -- Case of loop statement (more comments ???)
16985 if Nkind (Type_Decl) = N_Loop_Statement then
16990 Indic := Parent (R);
16991 while Present (Indic)
16992 and then Nkind (Indic) /= N_Subtype_Indication
16994 Indic := Parent (Indic);
16997 if Present (Indic) then
16998 Def_Id := Etype (Subtype_Mark (Indic));
17000 Insert_Range_Checks
17006 Do_Before => True);
17010 -- All other cases (more comments ???)
17013 Def_Id := Defining_Identifier (Type_Decl);
17015 if (Ekind (Def_Id) = E_Record_Type
17016 and then Depends_On_Discriminant (R))
17018 (Ekind (Def_Id) = E_Protected_Type
17019 and then Has_Discriminants (Def_Id))
17021 Append_Range_Checks
17022 (R_Checks, Check_List, Def_Id, Sloc (Type_Decl), R);
17025 Insert_Range_Checks
17026 (R_Checks, Type_Decl, Def_Id, Sloc (Type_Decl), R);
17034 elsif Expander_Active then
17035 Get_Index_Bounds (R, Lo, Hi);
17036 Force_Evaluation (Lo);
17037 Force_Evaluation (Hi);
17039 end Process_Range_Expr_In_Decl;
17041 --------------------------------------
17042 -- Process_Real_Range_Specification --
17043 --------------------------------------
17045 procedure Process_Real_Range_Specification (Def : Node_Id) is
17046 Spec : constant Node_Id := Real_Range_Specification (Def);
17049 Err : Boolean := False;
17051 procedure Analyze_Bound (N : Node_Id);
17052 -- Analyze and check one bound
17054 -------------------
17055 -- Analyze_Bound --
17056 -------------------
17058 procedure Analyze_Bound (N : Node_Id) is
17060 Analyze_And_Resolve (N, Any_Real);
17062 if not Is_OK_Static_Expression (N) then
17063 Flag_Non_Static_Expr
17064 ("bound in real type definition is not static!", N);
17069 -- Start of processing for Process_Real_Range_Specification
17072 if Present (Spec) then
17073 Lo := Low_Bound (Spec);
17074 Hi := High_Bound (Spec);
17075 Analyze_Bound (Lo);
17076 Analyze_Bound (Hi);
17078 -- If error, clear away junk range specification
17081 Set_Real_Range_Specification (Def, Empty);
17084 end Process_Real_Range_Specification;
17086 ---------------------
17087 -- Process_Subtype --
17088 ---------------------
17090 function Process_Subtype
17092 Related_Nod : Node_Id;
17093 Related_Id : Entity_Id := Empty;
17094 Suffix : Character := ' ') return Entity_Id
17097 Def_Id : Entity_Id;
17098 Error_Node : Node_Id;
17099 Full_View_Id : Entity_Id;
17100 Subtype_Mark_Id : Entity_Id;
17102 May_Have_Null_Exclusion : Boolean;
17104 procedure Check_Incomplete (T : Entity_Id);
17105 -- Called to verify that an incomplete type is not used prematurely
17107 ----------------------
17108 -- Check_Incomplete --
17109 ----------------------
17111 procedure Check_Incomplete (T : Entity_Id) is
17113 -- Ada 2005 (AI-412): Incomplete subtypes are legal
17115 if Ekind (Root_Type (Entity (T))) = E_Incomplete_Type
17117 not (Ada_Version >= Ada_05
17119 (Nkind (Parent (T)) = N_Subtype_Declaration
17121 (Nkind (Parent (T)) = N_Subtype_Indication
17122 and then Nkind (Parent (Parent (T))) =
17123 N_Subtype_Declaration)))
17125 Error_Msg_N ("invalid use of type before its full declaration", T);
17127 end Check_Incomplete;
17129 -- Start of processing for Process_Subtype
17132 -- Case of no constraints present
17134 if Nkind (S) /= N_Subtype_Indication then
17136 Check_Incomplete (S);
17139 -- Ada 2005 (AI-231): Static check
17141 if Ada_Version >= Ada_05
17142 and then Present (P)
17143 and then Null_Exclusion_Present (P)
17144 and then Nkind (P) /= N_Access_To_Object_Definition
17145 and then not Is_Access_Type (Entity (S))
17147 Error_Msg_N ("`NOT NULL` only allowed for an access type", S);
17150 -- The following is ugly, can't we have a range or even a flag???
17152 May_Have_Null_Exclusion :=
17153 Nkind_In (P, N_Access_Definition,
17154 N_Access_Function_Definition,
17155 N_Access_Procedure_Definition,
17156 N_Access_To_Object_Definition,
17158 N_Component_Definition)
17160 Nkind_In (P, N_Derived_Type_Definition,
17161 N_Discriminant_Specification,
17162 N_Formal_Object_Declaration,
17163 N_Object_Declaration,
17164 N_Object_Renaming_Declaration,
17165 N_Parameter_Specification,
17166 N_Subtype_Declaration);
17168 -- Create an Itype that is a duplicate of Entity (S) but with the
17169 -- null-exclusion attribute
17171 if May_Have_Null_Exclusion
17172 and then Is_Access_Type (Entity (S))
17173 and then Null_Exclusion_Present (P)
17175 -- No need to check the case of an access to object definition.
17176 -- It is correct to define double not-null pointers.
17179 -- type Not_Null_Int_Ptr is not null access Integer;
17180 -- type Acc is not null access Not_Null_Int_Ptr;
17182 and then Nkind (P) /= N_Access_To_Object_Definition
17184 if Can_Never_Be_Null (Entity (S)) then
17185 case Nkind (Related_Nod) is
17186 when N_Full_Type_Declaration =>
17187 if Nkind (Type_Definition (Related_Nod))
17188 in N_Array_Type_Definition
17192 (Component_Definition
17193 (Type_Definition (Related_Nod)));
17196 Subtype_Indication (Type_Definition (Related_Nod));
17199 when N_Subtype_Declaration =>
17200 Error_Node := Subtype_Indication (Related_Nod);
17202 when N_Object_Declaration =>
17203 Error_Node := Object_Definition (Related_Nod);
17205 when N_Component_Declaration =>
17207 Subtype_Indication (Component_Definition (Related_Nod));
17209 when N_Allocator =>
17210 Error_Node := Expression (Related_Nod);
17213 pragma Assert (False);
17214 Error_Node := Related_Nod;
17218 ("`NOT NULL` not allowed (& already excludes null)",
17224 Create_Null_Excluding_Itype
17226 Related_Nod => P));
17227 Set_Entity (S, Etype (S));
17232 -- Case of constraint present, so that we have an N_Subtype_Indication
17233 -- node (this node is created only if constraints are present).
17236 Find_Type (Subtype_Mark (S));
17238 if Nkind (Parent (S)) /= N_Access_To_Object_Definition
17240 (Nkind (Parent (S)) = N_Subtype_Declaration
17241 and then Is_Itype (Defining_Identifier (Parent (S))))
17243 Check_Incomplete (Subtype_Mark (S));
17247 Subtype_Mark_Id := Entity (Subtype_Mark (S));
17249 -- Explicit subtype declaration case
17251 if Nkind (P) = N_Subtype_Declaration then
17252 Def_Id := Defining_Identifier (P);
17254 -- Explicit derived type definition case
17256 elsif Nkind (P) = N_Derived_Type_Definition then
17257 Def_Id := Defining_Identifier (Parent (P));
17259 -- Implicit case, the Def_Id must be created as an implicit type.
17260 -- The one exception arises in the case of concurrent types, array
17261 -- and access types, where other subsidiary implicit types may be
17262 -- created and must appear before the main implicit type. In these
17263 -- cases we leave Def_Id set to Empty as a signal that Create_Itype
17264 -- has not yet been called to create Def_Id.
17267 if Is_Array_Type (Subtype_Mark_Id)
17268 or else Is_Concurrent_Type (Subtype_Mark_Id)
17269 or else Is_Access_Type (Subtype_Mark_Id)
17273 -- For the other cases, we create a new unattached Itype,
17274 -- and set the indication to ensure it gets attached later.
17278 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
17282 -- If the kind of constraint is invalid for this kind of type,
17283 -- then give an error, and then pretend no constraint was given.
17285 if not Is_Valid_Constraint_Kind
17286 (Ekind (Subtype_Mark_Id), Nkind (Constraint (S)))
17289 ("incorrect constraint for this kind of type", Constraint (S));
17291 Rewrite (S, New_Copy_Tree (Subtype_Mark (S)));
17293 -- Set Ekind of orphan itype, to prevent cascaded errors
17295 if Present (Def_Id) then
17296 Set_Ekind (Def_Id, Ekind (Any_Type));
17299 -- Make recursive call, having got rid of the bogus constraint
17301 return Process_Subtype (S, Related_Nod, Related_Id, Suffix);
17304 -- Remaining processing depends on type
17306 case Ekind (Subtype_Mark_Id) is
17307 when Access_Kind =>
17308 Constrain_Access (Def_Id, S, Related_Nod);
17311 and then Is_Itype (Designated_Type (Def_Id))
17312 and then Nkind (Related_Nod) = N_Subtype_Declaration
17313 and then not Is_Incomplete_Type (Designated_Type (Def_Id))
17315 Build_Itype_Reference
17316 (Designated_Type (Def_Id), Related_Nod);
17320 Constrain_Array (Def_Id, S, Related_Nod, Related_Id, Suffix);
17322 when Decimal_Fixed_Point_Kind =>
17323 Constrain_Decimal (Def_Id, S);
17325 when Enumeration_Kind =>
17326 Constrain_Enumeration (Def_Id, S);
17328 when Ordinary_Fixed_Point_Kind =>
17329 Constrain_Ordinary_Fixed (Def_Id, S);
17332 Constrain_Float (Def_Id, S);
17334 when Integer_Kind =>
17335 Constrain_Integer (Def_Id, S);
17337 when E_Record_Type |
17340 E_Incomplete_Type =>
17341 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
17343 if Ekind (Def_Id) = E_Incomplete_Type then
17344 Set_Private_Dependents (Def_Id, New_Elmt_List);
17347 when Private_Kind =>
17348 Constrain_Discriminated_Type (Def_Id, S, Related_Nod);
17349 Set_Private_Dependents (Def_Id, New_Elmt_List);
17351 -- In case of an invalid constraint prevent further processing
17352 -- since the type constructed is missing expected fields.
17354 if Etype (Def_Id) = Any_Type then
17358 -- If the full view is that of a task with discriminants,
17359 -- we must constrain both the concurrent type and its
17360 -- corresponding record type. Otherwise we will just propagate
17361 -- the constraint to the full view, if available.
17363 if Present (Full_View (Subtype_Mark_Id))
17364 and then Has_Discriminants (Subtype_Mark_Id)
17365 and then Is_Concurrent_Type (Full_View (Subtype_Mark_Id))
17368 Create_Itype (E_Void, Related_Nod, Related_Id, Suffix);
17370 Set_Entity (Subtype_Mark (S), Full_View (Subtype_Mark_Id));
17371 Constrain_Concurrent (Full_View_Id, S,
17372 Related_Nod, Related_Id, Suffix);
17373 Set_Entity (Subtype_Mark (S), Subtype_Mark_Id);
17374 Set_Full_View (Def_Id, Full_View_Id);
17376 -- Introduce an explicit reference to the private subtype,
17377 -- to prevent scope anomalies in gigi if first use appears
17378 -- in a nested context, e.g. a later function body.
17379 -- Should this be generated in other contexts than a full
17380 -- type declaration?
17382 if Is_Itype (Def_Id)
17384 Nkind (Parent (P)) = N_Full_Type_Declaration
17386 Build_Itype_Reference (Def_Id, Parent (P));
17390 Prepare_Private_Subtype_Completion (Def_Id, Related_Nod);
17393 when Concurrent_Kind =>
17394 Constrain_Concurrent (Def_Id, S,
17395 Related_Nod, Related_Id, Suffix);
17398 Error_Msg_N ("invalid subtype mark in subtype indication", S);
17401 -- Size and Convention are always inherited from the base type
17403 Set_Size_Info (Def_Id, (Subtype_Mark_Id));
17404 Set_Convention (Def_Id, Convention (Subtype_Mark_Id));
17408 end Process_Subtype;
17410 ---------------------------------------
17411 -- Check_Anonymous_Access_Components --
17412 ---------------------------------------
17414 procedure Check_Anonymous_Access_Components
17415 (Typ_Decl : Node_Id;
17418 Comp_List : Node_Id)
17420 Loc : constant Source_Ptr := Sloc (Typ_Decl);
17421 Anon_Access : Entity_Id;
17424 Comp_Def : Node_Id;
17426 Type_Def : Node_Id;
17428 procedure Build_Incomplete_Type_Declaration;
17429 -- If the record type contains components that include an access to the
17430 -- current record, then create an incomplete type declaration for the
17431 -- record, to be used as the designated type of the anonymous access.
17432 -- This is done only once, and only if there is no previous partial
17433 -- view of the type.
17435 function Designates_T (Subt : Node_Id) return Boolean;
17436 -- Check whether a node designates the enclosing record type, or 'Class
17439 function Mentions_T (Acc_Def : Node_Id) return Boolean;
17440 -- Check whether an access definition includes a reference to
17441 -- the enclosing record type. The reference can be a subtype mark
17442 -- in the access definition itself, a 'Class attribute reference, or
17443 -- recursively a reference appearing in a parameter specification
17444 -- or result definition of an access_to_subprogram definition.
17446 --------------------------------------
17447 -- Build_Incomplete_Type_Declaration --
17448 --------------------------------------
17450 procedure Build_Incomplete_Type_Declaration is
17455 -- Is_Tagged indicates whether the type is tagged. It is tagged if
17456 -- it's "is new ... with record" or else "is tagged record ...".
17458 Is_Tagged : constant Boolean :=
17459 (Nkind (Type_Definition (Typ_Decl)) = N_Derived_Type_Definition
17462 (Record_Extension_Part (Type_Definition (Typ_Decl))))
17464 (Nkind (Type_Definition (Typ_Decl)) = N_Record_Definition
17465 and then Tagged_Present (Type_Definition (Typ_Decl)));
17468 -- If there is a previous partial view, no need to create a new one
17469 -- If the partial view, given by Prev, is incomplete, If Prev is
17470 -- a private declaration, full declaration is flagged accordingly.
17472 if Prev /= Typ then
17474 Make_Class_Wide_Type (Prev);
17475 Set_Class_Wide_Type (Typ, Class_Wide_Type (Prev));
17476 Set_Etype (Class_Wide_Type (Typ), Typ);
17481 elsif Has_Private_Declaration (Typ) then
17483 -- If we refer to T'Class inside T, and T is the completion of a
17484 -- private type, then we need to make sure the class-wide type
17488 Make_Class_Wide_Type (Typ);
17493 -- If there was a previous anonymous access type, the incomplete
17494 -- type declaration will have been created already.
17496 elsif Present (Current_Entity (Typ))
17497 and then Ekind (Current_Entity (Typ)) = E_Incomplete_Type
17498 and then Full_View (Current_Entity (Typ)) = Typ
17503 Inc_T := Make_Defining_Identifier (Loc, Chars (Typ));
17504 Decl := Make_Incomplete_Type_Declaration (Loc, Inc_T);
17506 -- Type has already been inserted into the current scope.
17507 -- Remove it, and add incomplete declaration for type, so
17508 -- that subsequent anonymous access types can use it.
17509 -- The entity is unchained from the homonym list and from
17510 -- immediate visibility. After analysis, the entity in the
17511 -- incomplete declaration becomes immediately visible in the
17512 -- record declaration that follows.
17514 H := Current_Entity (Typ);
17517 Set_Name_Entity_Id (Chars (Typ), Homonym (Typ));
17520 and then Homonym (H) /= Typ
17522 H := Homonym (Typ);
17525 Set_Homonym (H, Homonym (Typ));
17528 Insert_Before (Typ_Decl, Decl);
17530 Set_Full_View (Inc_T, Typ);
17533 -- Create a common class-wide type for both views, and set
17534 -- the Etype of the class-wide type to the full view.
17536 Make_Class_Wide_Type (Inc_T);
17537 Set_Class_Wide_Type (Typ, Class_Wide_Type (Inc_T));
17538 Set_Etype (Class_Wide_Type (Typ), Typ);
17541 end Build_Incomplete_Type_Declaration;
17547 function Designates_T (Subt : Node_Id) return Boolean is
17548 Type_Id : constant Name_Id := Chars (Typ);
17550 function Names_T (Nam : Node_Id) return Boolean;
17551 -- The record type has not been introduced in the current scope
17552 -- yet, so we must examine the name of the type itself, either
17553 -- an identifier T, or an expanded name of the form P.T, where
17554 -- P denotes the current scope.
17560 function Names_T (Nam : Node_Id) return Boolean is
17562 if Nkind (Nam) = N_Identifier then
17563 return Chars (Nam) = Type_Id;
17565 elsif Nkind (Nam) = N_Selected_Component then
17566 if Chars (Selector_Name (Nam)) = Type_Id then
17567 if Nkind (Prefix (Nam)) = N_Identifier then
17568 return Chars (Prefix (Nam)) = Chars (Current_Scope);
17570 elsif Nkind (Prefix (Nam)) = N_Selected_Component then
17571 return Chars (Selector_Name (Prefix (Nam))) =
17572 Chars (Current_Scope);
17586 -- Start of processing for Designates_T
17589 if Nkind (Subt) = N_Identifier then
17590 return Chars (Subt) = Type_Id;
17592 -- Reference can be through an expanded name which has not been
17593 -- analyzed yet, and which designates enclosing scopes.
17595 elsif Nkind (Subt) = N_Selected_Component then
17596 if Names_T (Subt) then
17599 -- Otherwise it must denote an entity that is already visible.
17600 -- The access definition may name a subtype of the enclosing
17601 -- type, if there is a previous incomplete declaration for it.
17604 Find_Selected_Component (Subt);
17606 Is_Entity_Name (Subt)
17607 and then Scope (Entity (Subt)) = Current_Scope
17609 (Chars (Base_Type (Entity (Subt))) = Type_Id
17611 (Is_Class_Wide_Type (Entity (Subt))
17613 Chars (Etype (Base_Type (Entity (Subt)))) =
17617 -- A reference to the current type may appear as the prefix of
17618 -- a 'Class attribute.
17620 elsif Nkind (Subt) = N_Attribute_Reference
17621 and then Attribute_Name (Subt) = Name_Class
17623 return Names_T (Prefix (Subt));
17634 function Mentions_T (Acc_Def : Node_Id) return Boolean is
17635 Param_Spec : Node_Id;
17637 Acc_Subprg : constant Node_Id :=
17638 Access_To_Subprogram_Definition (Acc_Def);
17641 if No (Acc_Subprg) then
17642 return Designates_T (Subtype_Mark (Acc_Def));
17645 -- Component is an access_to_subprogram: examine its formals,
17646 -- and result definition in the case of an access_to_function.
17648 Param_Spec := First (Parameter_Specifications (Acc_Subprg));
17649 while Present (Param_Spec) loop
17650 if Nkind (Parameter_Type (Param_Spec)) = N_Access_Definition
17651 and then Mentions_T (Parameter_Type (Param_Spec))
17655 elsif Designates_T (Parameter_Type (Param_Spec)) then
17662 if Nkind (Acc_Subprg) = N_Access_Function_Definition then
17663 if Nkind (Result_Definition (Acc_Subprg)) =
17664 N_Access_Definition
17666 return Mentions_T (Result_Definition (Acc_Subprg));
17668 return Designates_T (Result_Definition (Acc_Subprg));
17675 -- Start of processing for Check_Anonymous_Access_Components
17678 if No (Comp_List) then
17682 Comp := First (Component_Items (Comp_List));
17683 while Present (Comp) loop
17684 if Nkind (Comp) = N_Component_Declaration
17686 (Access_Definition (Component_Definition (Comp)))
17688 Mentions_T (Access_Definition (Component_Definition (Comp)))
17690 Comp_Def := Component_Definition (Comp);
17692 Access_To_Subprogram_Definition
17693 (Access_Definition (Comp_Def));
17695 Build_Incomplete_Type_Declaration;
17697 Make_Defining_Identifier (Loc,
17698 Chars => New_Internal_Name ('S'));
17700 -- Create a declaration for the anonymous access type: either
17701 -- an access_to_object or an access_to_subprogram.
17703 if Present (Acc_Def) then
17704 if Nkind (Acc_Def) = N_Access_Function_Definition then
17706 Make_Access_Function_Definition (Loc,
17707 Parameter_Specifications =>
17708 Parameter_Specifications (Acc_Def),
17709 Result_Definition => Result_Definition (Acc_Def));
17712 Make_Access_Procedure_Definition (Loc,
17713 Parameter_Specifications =>
17714 Parameter_Specifications (Acc_Def));
17719 Make_Access_To_Object_Definition (Loc,
17720 Subtype_Indication =>
17723 (Access_Definition (Comp_Def))));
17725 Set_Constant_Present
17726 (Type_Def, Constant_Present (Access_Definition (Comp_Def)));
17728 (Type_Def, All_Present (Access_Definition (Comp_Def)));
17731 Set_Null_Exclusion_Present
17733 Null_Exclusion_Present (Access_Definition (Comp_Def)));
17736 Make_Full_Type_Declaration (Loc,
17737 Defining_Identifier => Anon_Access,
17738 Type_Definition => Type_Def);
17740 Insert_Before (Typ_Decl, Decl);
17743 -- If an access to object, Preserve entity of designated type,
17744 -- for ASIS use, before rewriting the component definition.
17746 if No (Acc_Def) then
17751 Desig := Entity (Subtype_Indication (Type_Def));
17753 -- If the access definition is to the current record,
17754 -- the visible entity at this point is an incomplete
17755 -- type. Retrieve the full view to simplify ASIS queries
17757 if Ekind (Desig) = E_Incomplete_Type then
17758 Desig := Full_View (Desig);
17762 (Subtype_Mark (Access_Definition (Comp_Def)), Desig);
17767 Make_Component_Definition (Loc,
17768 Subtype_Indication =>
17769 New_Occurrence_Of (Anon_Access, Loc)));
17771 if Ekind (Designated_Type (Anon_Access)) = E_Subprogram_Type then
17772 Set_Ekind (Anon_Access, E_Anonymous_Access_Subprogram_Type);
17774 Set_Ekind (Anon_Access, E_Anonymous_Access_Type);
17777 Set_Is_Local_Anonymous_Access (Anon_Access);
17783 if Present (Variant_Part (Comp_List)) then
17787 V := First_Non_Pragma (Variants (Variant_Part (Comp_List)));
17788 while Present (V) loop
17789 Check_Anonymous_Access_Components
17790 (Typ_Decl, Typ, Prev, Component_List (V));
17791 Next_Non_Pragma (V);
17795 end Check_Anonymous_Access_Components;
17797 --------------------------------
17798 -- Preanalyze_Spec_Expression --
17799 --------------------------------
17801 procedure Preanalyze_Spec_Expression (N : Node_Id; T : Entity_Id) is
17802 Save_In_Spec_Expression : constant Boolean := In_Spec_Expression;
17804 In_Spec_Expression := True;
17805 Preanalyze_And_Resolve (N, T);
17806 In_Spec_Expression := Save_In_Spec_Expression;
17807 end Preanalyze_Spec_Expression;
17809 -----------------------------
17810 -- Record_Type_Declaration --
17811 -----------------------------
17813 procedure Record_Type_Declaration
17818 Def : constant Node_Id := Type_Definition (N);
17819 Is_Tagged : Boolean;
17820 Tag_Comp : Entity_Id;
17823 -- These flags must be initialized before calling Process_Discriminants
17824 -- because this routine makes use of them.
17826 Set_Ekind (T, E_Record_Type);
17828 Init_Size_Align (T);
17829 Set_Interfaces (T, No_Elist);
17830 Set_Stored_Constraint (T, No_Elist);
17834 if Ada_Version < Ada_05
17835 or else not Interface_Present (Def)
17837 -- The flag Is_Tagged_Type might have already been set by
17838 -- Find_Type_Name if it detected an error for declaration T. This
17839 -- arises in the case of private tagged types where the full view
17840 -- omits the word tagged.
17843 Tagged_Present (Def)
17844 or else (Serious_Errors_Detected > 0 and then Is_Tagged_Type (T));
17846 Set_Is_Tagged_Type (T, Is_Tagged);
17847 Set_Is_Limited_Record (T, Limited_Present (Def));
17849 -- Type is abstract if full declaration carries keyword, or if
17850 -- previous partial view did.
17852 Set_Is_Abstract_Type (T, Is_Abstract_Type (T)
17853 or else Abstract_Present (Def));
17857 Analyze_Interface_Declaration (T, Def);
17859 if Present (Discriminant_Specifications (N)) then
17861 ("interface types cannot have discriminants",
17862 Defining_Identifier
17863 (First (Discriminant_Specifications (N))));
17867 -- First pass: if there are self-referential access components,
17868 -- create the required anonymous access type declarations, and if
17869 -- need be an incomplete type declaration for T itself.
17871 Check_Anonymous_Access_Components (N, T, Prev, Component_List (Def));
17873 if Ada_Version >= Ada_05
17874 and then Present (Interface_List (Def))
17876 Check_Interfaces (N, Def);
17879 Ifaces_List : Elist_Id;
17882 -- Ada 2005 (AI-251): Collect the list of progenitors that are not
17883 -- already in the parents.
17887 Ifaces_List => Ifaces_List,
17888 Exclude_Parents => True);
17890 Set_Interfaces (T, Ifaces_List);
17894 -- Records constitute a scope for the component declarations within.
17895 -- The scope is created prior to the processing of these declarations.
17896 -- Discriminants are processed first, so that they are visible when
17897 -- processing the other components. The Ekind of the record type itself
17898 -- is set to E_Record_Type (subtypes appear as E_Record_Subtype).
17900 -- Enter record scope
17904 -- If an incomplete or private type declaration was already given for
17905 -- the type, then this scope already exists, and the discriminants have
17906 -- been declared within. We must verify that the full declaration
17907 -- matches the incomplete one.
17909 Check_Or_Process_Discriminants (N, T, Prev);
17911 Set_Is_Constrained (T, not Has_Discriminants (T));
17912 Set_Has_Delayed_Freeze (T, True);
17914 -- For tagged types add a manually analyzed component corresponding
17915 -- to the component _tag, the corresponding piece of tree will be
17916 -- expanded as part of the freezing actions if it is not a CPP_Class.
17920 -- Do not add the tag unless we are in expansion mode
17922 if Expander_Active then
17923 Tag_Comp := Make_Defining_Identifier (Sloc (Def), Name_uTag);
17924 Enter_Name (Tag_Comp);
17926 Set_Ekind (Tag_Comp, E_Component);
17927 Set_Is_Tag (Tag_Comp);
17928 Set_Is_Aliased (Tag_Comp);
17929 Set_Etype (Tag_Comp, RTE (RE_Tag));
17930 Set_DT_Entry_Count (Tag_Comp, No_Uint);
17931 Set_Original_Record_Component (Tag_Comp, Tag_Comp);
17932 Init_Component_Location (Tag_Comp);
17934 -- Ada 2005 (AI-251): Addition of the Tag corresponding to all the
17935 -- implemented interfaces.
17937 if Has_Interfaces (T) then
17938 Add_Interface_Tag_Components (N, T);
17942 Make_Class_Wide_Type (T);
17943 Set_Primitive_Operations (T, New_Elmt_List);
17946 -- We must suppress range checks when processing the components
17947 -- of a record in the presence of discriminants, since we don't
17948 -- want spurious checks to be generated during their analysis, but
17949 -- must reset the Suppress_Range_Checks flags after having processed
17950 -- the record definition.
17952 -- Note: this is the only use of Kill_Range_Checks, and is a bit odd,
17953 -- couldn't we just use the normal range check suppression method here.
17954 -- That would seem cleaner ???
17956 if Has_Discriminants (T) and then not Range_Checks_Suppressed (T) then
17957 Set_Kill_Range_Checks (T, True);
17958 Record_Type_Definition (Def, Prev);
17959 Set_Kill_Range_Checks (T, False);
17961 Record_Type_Definition (Def, Prev);
17964 -- Exit from record scope
17968 -- Ada 2005 (AI-251 and AI-345): Derive the interface subprograms of all
17969 -- the implemented interfaces and associate them an aliased entity.
17972 and then not Is_Empty_List (Interface_List (Def))
17974 Derive_Progenitor_Subprograms (T, T);
17976 end Record_Type_Declaration;
17978 ----------------------------
17979 -- Record_Type_Definition --
17980 ----------------------------
17982 procedure Record_Type_Definition (Def : Node_Id; Prev_T : Entity_Id) is
17983 Component : Entity_Id;
17984 Ctrl_Components : Boolean := False;
17985 Final_Storage_Only : Boolean;
17989 if Ekind (Prev_T) = E_Incomplete_Type then
17990 T := Full_View (Prev_T);
17995 Final_Storage_Only := not Is_Controlled (T);
17997 -- Ada 2005: check whether an explicit Limited is present in a derived
17998 -- type declaration.
18000 if Nkind (Parent (Def)) = N_Derived_Type_Definition
18001 and then Limited_Present (Parent (Def))
18003 Set_Is_Limited_Record (T);
18006 -- If the component list of a record type is defined by the reserved
18007 -- word null and there is no discriminant part, then the record type has
18008 -- no components and all records of the type are null records (RM 3.7)
18009 -- This procedure is also called to process the extension part of a
18010 -- record extension, in which case the current scope may have inherited
18014 or else No (Component_List (Def))
18015 or else Null_Present (Component_List (Def))
18020 Analyze_Declarations (Component_Items (Component_List (Def)));
18022 if Present (Variant_Part (Component_List (Def))) then
18023 Analyze (Variant_Part (Component_List (Def)));
18027 -- After completing the semantic analysis of the record definition,
18028 -- record components, both new and inherited, are accessible. Set their
18029 -- kind accordingly. Exclude malformed itypes from illegal declarations,
18030 -- whose Ekind may be void.
18032 Component := First_Entity (Current_Scope);
18033 while Present (Component) loop
18034 if Ekind (Component) = E_Void
18035 and then not Is_Itype (Component)
18037 Set_Ekind (Component, E_Component);
18038 Init_Component_Location (Component);
18041 if Has_Task (Etype (Component)) then
18045 if Ekind (Component) /= E_Component then
18048 -- Do not set Has_Controlled_Component on a class-wide equivalent
18049 -- type. See Make_CW_Equivalent_Type.
18051 elsif not Is_Class_Wide_Equivalent_Type (T)
18052 and then (Has_Controlled_Component (Etype (Component))
18053 or else (Chars (Component) /= Name_uParent
18054 and then Is_Controlled (Etype (Component))))
18056 Set_Has_Controlled_Component (T, True);
18057 Final_Storage_Only :=
18059 and then Finalize_Storage_Only (Etype (Component));
18060 Ctrl_Components := True;
18063 Next_Entity (Component);
18066 -- A Type is Finalize_Storage_Only only if all its controlled components
18069 if Ctrl_Components then
18070 Set_Finalize_Storage_Only (T, Final_Storage_Only);
18073 -- Place reference to end record on the proper entity, which may
18074 -- be a partial view.
18076 if Present (Def) then
18077 Process_End_Label (Def, 'e', Prev_T);
18079 end Record_Type_Definition;
18081 ------------------------
18082 -- Replace_Components --
18083 ------------------------
18085 procedure Replace_Components (Typ : Entity_Id; Decl : Node_Id) is
18086 function Process (N : Node_Id) return Traverse_Result;
18092 function Process (N : Node_Id) return Traverse_Result is
18096 if Nkind (N) = N_Discriminant_Specification then
18097 Comp := First_Discriminant (Typ);
18098 while Present (Comp) loop
18099 if Chars (Comp) = Chars (Defining_Identifier (N)) then
18100 Set_Defining_Identifier (N, Comp);
18104 Next_Discriminant (Comp);
18107 elsif Nkind (N) = N_Component_Declaration then
18108 Comp := First_Component (Typ);
18109 while Present (Comp) loop
18110 if Chars (Comp) = Chars (Defining_Identifier (N)) then
18111 Set_Defining_Identifier (N, Comp);
18115 Next_Component (Comp);
18122 procedure Replace is new Traverse_Proc (Process);
18124 -- Start of processing for Replace_Components
18128 end Replace_Components;
18130 -------------------------------
18131 -- Set_Completion_Referenced --
18132 -------------------------------
18134 procedure Set_Completion_Referenced (E : Entity_Id) is
18136 -- If in main unit, mark entity that is a completion as referenced,
18137 -- warnings go on the partial view when needed.
18139 if In_Extended_Main_Source_Unit (E) then
18140 Set_Referenced (E);
18142 end Set_Completion_Referenced;
18144 ---------------------
18145 -- Set_Fixed_Range --
18146 ---------------------
18148 -- The range for fixed-point types is complicated by the fact that we
18149 -- do not know the exact end points at the time of the declaration. This
18150 -- is true for three reasons:
18152 -- A size clause may affect the fudging of the end-points
18153 -- A small clause may affect the values of the end-points
18154 -- We try to include the end-points if it does not affect the size
18156 -- This means that the actual end-points must be established at the point
18157 -- when the type is frozen. Meanwhile, we first narrow the range as
18158 -- permitted (so that it will fit if necessary in a small specified size),
18159 -- and then build a range subtree with these narrowed bounds.
18161 -- Set_Fixed_Range constructs the range from real literal values, and sets
18162 -- the range as the Scalar_Range of the given fixed-point type entity.
18164 -- The parent of this range is set to point to the entity so that it is
18165 -- properly hooked into the tree (unlike normal Scalar_Range entries for
18166 -- other scalar types, which are just pointers to the range in the
18167 -- original tree, this would otherwise be an orphan).
18169 -- The tree is left unanalyzed. When the type is frozen, the processing
18170 -- in Freeze.Freeze_Fixed_Point_Type notices that the range is not
18171 -- analyzed, and uses this as an indication that it should complete
18172 -- work on the range (it will know the final small and size values).
18174 procedure Set_Fixed_Range
18180 S : constant Node_Id :=
18182 Low_Bound => Make_Real_Literal (Loc, Lo),
18183 High_Bound => Make_Real_Literal (Loc, Hi));
18185 Set_Scalar_Range (E, S);
18187 end Set_Fixed_Range;
18189 ----------------------------------
18190 -- Set_Scalar_Range_For_Subtype --
18191 ----------------------------------
18193 procedure Set_Scalar_Range_For_Subtype
18194 (Def_Id : Entity_Id;
18198 Kind : constant Entity_Kind := Ekind (Def_Id);
18201 Set_Scalar_Range (Def_Id, R);
18203 -- We need to link the range into the tree before resolving it so
18204 -- that types that are referenced, including importantly the subtype
18205 -- itself, are properly frozen (Freeze_Expression requires that the
18206 -- expression be properly linked into the tree). Of course if it is
18207 -- already linked in, then we do not disturb the current link.
18209 if No (Parent (R)) then
18210 Set_Parent (R, Def_Id);
18213 -- Reset the kind of the subtype during analysis of the range, to
18214 -- catch possible premature use in the bounds themselves.
18216 Set_Ekind (Def_Id, E_Void);
18217 Process_Range_Expr_In_Decl (R, Subt);
18218 Set_Ekind (Def_Id, Kind);
18219 end Set_Scalar_Range_For_Subtype;
18221 --------------------------------------------------------
18222 -- Set_Stored_Constraint_From_Discriminant_Constraint --
18223 --------------------------------------------------------
18225 procedure Set_Stored_Constraint_From_Discriminant_Constraint
18229 -- Make sure set if encountered during Expand_To_Stored_Constraint
18231 Set_Stored_Constraint (E, No_Elist);
18233 -- Give it the right value
18235 if Is_Constrained (E) and then Has_Discriminants (E) then
18236 Set_Stored_Constraint (E,
18237 Expand_To_Stored_Constraint (E, Discriminant_Constraint (E)));
18239 end Set_Stored_Constraint_From_Discriminant_Constraint;
18241 -------------------------------------
18242 -- Signed_Integer_Type_Declaration --
18243 -------------------------------------
18245 procedure Signed_Integer_Type_Declaration (T : Entity_Id; Def : Node_Id) is
18246 Implicit_Base : Entity_Id;
18247 Base_Typ : Entity_Id;
18250 Errs : Boolean := False;
18254 function Can_Derive_From (E : Entity_Id) return Boolean;
18255 -- Determine whether given bounds allow derivation from specified type
18257 procedure Check_Bound (Expr : Node_Id);
18258 -- Check bound to make sure it is integral and static. If not, post
18259 -- appropriate error message and set Errs flag
18261 ---------------------
18262 -- Can_Derive_From --
18263 ---------------------
18265 -- Note we check both bounds against both end values, to deal with
18266 -- strange types like ones with a range of 0 .. -12341234.
18268 function Can_Derive_From (E : Entity_Id) return Boolean is
18269 Lo : constant Uint := Expr_Value (Type_Low_Bound (E));
18270 Hi : constant Uint := Expr_Value (Type_High_Bound (E));
18272 return Lo <= Lo_Val and then Lo_Val <= Hi
18274 Lo <= Hi_Val and then Hi_Val <= Hi;
18275 end Can_Derive_From;
18281 procedure Check_Bound (Expr : Node_Id) is
18283 -- If a range constraint is used as an integer type definition, each
18284 -- bound of the range must be defined by a static expression of some
18285 -- integer type, but the two bounds need not have the same integer
18286 -- type (Negative bounds are allowed.) (RM 3.5.4)
18288 if not Is_Integer_Type (Etype (Expr)) then
18290 ("integer type definition bounds must be of integer type", Expr);
18293 elsif not Is_OK_Static_Expression (Expr) then
18294 Flag_Non_Static_Expr
18295 ("non-static expression used for integer type bound!", Expr);
18298 -- The bounds are folded into literals, and we set their type to be
18299 -- universal, to avoid typing difficulties: we cannot set the type
18300 -- of the literal to the new type, because this would be a forward
18301 -- reference for the back end, and if the original type is user-
18302 -- defined this can lead to spurious semantic errors (e.g. 2928-003).
18305 if Is_Entity_Name (Expr) then
18306 Fold_Uint (Expr, Expr_Value (Expr), True);
18309 Set_Etype (Expr, Universal_Integer);
18313 -- Start of processing for Signed_Integer_Type_Declaration
18316 -- Create an anonymous base type
18319 Create_Itype (E_Signed_Integer_Type, Parent (Def), T, 'B');
18321 -- Analyze and check the bounds, they can be of any integer type
18323 Lo := Low_Bound (Def);
18324 Hi := High_Bound (Def);
18326 -- Arbitrarily use Integer as the type if either bound had an error
18328 if Hi = Error or else Lo = Error then
18329 Base_Typ := Any_Integer;
18330 Set_Error_Posted (T, True);
18332 -- Here both bounds are OK expressions
18335 Analyze_And_Resolve (Lo, Any_Integer);
18336 Analyze_And_Resolve (Hi, Any_Integer);
18342 Hi := Type_High_Bound (Standard_Long_Long_Integer);
18343 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
18346 -- Find type to derive from
18348 Lo_Val := Expr_Value (Lo);
18349 Hi_Val := Expr_Value (Hi);
18351 if Can_Derive_From (Standard_Short_Short_Integer) then
18352 Base_Typ := Base_Type (Standard_Short_Short_Integer);
18354 elsif Can_Derive_From (Standard_Short_Integer) then
18355 Base_Typ := Base_Type (Standard_Short_Integer);
18357 elsif Can_Derive_From (Standard_Integer) then
18358 Base_Typ := Base_Type (Standard_Integer);
18360 elsif Can_Derive_From (Standard_Long_Integer) then
18361 Base_Typ := Base_Type (Standard_Long_Integer);
18363 elsif Can_Derive_From (Standard_Long_Long_Integer) then
18364 Base_Typ := Base_Type (Standard_Long_Long_Integer);
18367 Base_Typ := Base_Type (Standard_Long_Long_Integer);
18368 Error_Msg_N ("integer type definition bounds out of range", Def);
18369 Hi := Type_High_Bound (Standard_Long_Long_Integer);
18370 Lo := Type_Low_Bound (Standard_Long_Long_Integer);
18374 -- Complete both implicit base and declared first subtype entities
18376 Set_Etype (Implicit_Base, Base_Typ);
18377 Set_Scalar_Range (Implicit_Base, Scalar_Range (Base_Typ));
18378 Set_Size_Info (Implicit_Base, (Base_Typ));
18379 Set_RM_Size (Implicit_Base, RM_Size (Base_Typ));
18380 Set_First_Rep_Item (Implicit_Base, First_Rep_Item (Base_Typ));
18382 Set_Ekind (T, E_Signed_Integer_Subtype);
18383 Set_Etype (T, Implicit_Base);
18385 Set_Size_Info (T, (Implicit_Base));
18386 Set_First_Rep_Item (T, First_Rep_Item (Implicit_Base));
18387 Set_Scalar_Range (T, Def);
18388 Set_RM_Size (T, UI_From_Int (Minimum_Size (T)));
18389 Set_Is_Constrained (T);
18390 end Signed_Integer_Type_Declaration;