2015-05-12 Robert Dewar <dewar@adacore.com>
[official-gcc.git] / gcc / ada / sem_ch7.adb
blob8af1f346ebccac1158abc27c626d8b9e0d8c16c8
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- S E M _ C H 7 --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2015, Free Software Foundation, Inc. --
10 -- --
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. --
20 -- --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
23 -- --
24 ------------------------------------------------------------------------------
26 -- This package contains the routines to process package specifications and
27 -- bodies. The most important semantic aspects of package processing are the
28 -- handling of private and full declarations, and the construction of dispatch
29 -- tables for tagged types.
31 with Aspects; use Aspects;
32 with Atree; use Atree;
33 with Debug; use Debug;
34 with Einfo; use Einfo;
35 with Elists; use Elists;
36 with Errout; use Errout;
37 with Exp_Disp; use Exp_Disp;
38 with Exp_Dist; use Exp_Dist;
39 with Exp_Dbug; use Exp_Dbug;
40 with Ghost; use Ghost;
41 with Lib; use Lib;
42 with Lib.Xref; use Lib.Xref;
43 with Namet; use Namet;
44 with Nmake; use Nmake;
45 with Nlists; use Nlists;
46 with Opt; use Opt;
47 with Output; use Output;
48 with Restrict; use Restrict;
49 with Sem; use Sem;
50 with Sem_Aux; use Sem_Aux;
51 with Sem_Cat; use Sem_Cat;
52 with Sem_Ch3; use Sem_Ch3;
53 with Sem_Ch6; use Sem_Ch6;
54 with Sem_Ch8; use Sem_Ch8;
55 with Sem_Ch10; use Sem_Ch10;
56 with Sem_Ch12; use Sem_Ch12;
57 with Sem_Ch13; use Sem_Ch13;
58 with Sem_Disp; use Sem_Disp;
59 with Sem_Eval; use Sem_Eval;
60 with Sem_Prag; use Sem_Prag;
61 with Sem_Util; use Sem_Util;
62 with Sem_Warn; use Sem_Warn;
63 with Snames; use Snames;
64 with Stand; use Stand;
65 with Sinfo; use Sinfo;
66 with Sinput; use Sinput;
67 with Style;
68 with Uintp; use Uintp;
70 package body Sem_Ch7 is
72 -----------------------------------
73 -- Handling private declarations --
74 -----------------------------------
76 -- The principle that each entity has a single defining occurrence clashes
77 -- with the presence of two separate definitions for private types: the
78 -- first is the private type declaration, and the second is the full type
79 -- declaration. It is important that all references to the type point to
80 -- the same defining occurrence, namely the first one. To enforce the two
81 -- separate views of the entity, the corresponding information is swapped
82 -- between the two declarations. Outside of the package, the defining
83 -- occurrence only contains the private declaration information, while in
84 -- the private part and the body of the package the defining occurrence
85 -- contains the full declaration. To simplify the swap, the defining
86 -- occurrence that currently holds the private declaration points to the
87 -- full declaration. During semantic processing the defining occurrence
88 -- also points to a list of private dependents, that is to say access types
89 -- or composite types whose designated types or component types are
90 -- subtypes or derived types of the private type in question. After the
91 -- full declaration has been seen, the private dependents are updated to
92 -- indicate that they have full definitions.
94 -----------------------
95 -- Local Subprograms --
96 -----------------------
98 procedure Analyze_Package_Body_Helper (N : Node_Id);
99 -- Does all the real work of Analyze_Package_Body
101 procedure Check_Anonymous_Access_Types
102 (Spec_Id : Entity_Id;
103 P_Body : Node_Id);
104 -- If the spec of a package has a limited_with_clause, it may declare
105 -- anonymous access types whose designated type is a limited view, such an
106 -- anonymous access return type for a function. This access type cannot be
107 -- elaborated in the spec itself, but it may need an itype reference if it
108 -- is used within a nested scope. In that case the itype reference is
109 -- created at the beginning of the corresponding package body and inserted
110 -- before other body declarations.
112 procedure Declare_Inherited_Private_Subprograms (Id : Entity_Id);
113 -- Called upon entering the private part of a public child package and the
114 -- body of a nested package, to potentially declare certain inherited
115 -- subprograms that were inherited by types in the visible part, but whose
116 -- declaration was deferred because the parent operation was private and
117 -- not visible at that point. These subprograms are located by traversing
118 -- the visible part declarations looking for non-private type extensions
119 -- and then examining each of the primitive operations of such types to
120 -- find those that were inherited but declared with a special internal
121 -- name. Each such operation is now declared as an operation with a normal
122 -- name (using the name of the parent operation) and replaces the previous
123 -- implicit operation in the primitive operations list of the type. If the
124 -- inherited private operation has been overridden, then it's replaced by
125 -- the overriding operation.
127 procedure Install_Package_Entity (Id : Entity_Id);
128 -- Supporting procedure for Install_{Visible,Private}_Declarations. Places
129 -- one entity on its visibility chain, and recurses on the visible part if
130 -- the entity is an inner package.
132 function Is_Private_Base_Type (E : Entity_Id) return Boolean;
133 -- True for a private type that is not a subtype
135 function Is_Visible_Dependent (Dep : Entity_Id) return Boolean;
136 -- If the private dependent is a private type whose full view is derived
137 -- from the parent type, its full properties are revealed only if we are in
138 -- the immediate scope of the private dependent. Should this predicate be
139 -- tightened further???
141 function Requires_Completion_In_Body
142 (Id : Entity_Id;
143 Pack_Id : Entity_Id) return Boolean;
144 -- Subsidiary to routines Unit_Requires_Body and Unit_Requires_Body_Info.
145 -- Determine whether entity Id declared in package spec Pack_Id requires
146 -- completion in a package body.
148 procedure Unit_Requires_Body_Info (Pack_Id : Entity_Id);
149 -- Outputs info messages showing why package Pack_Id requires a body. The
150 -- caller has checked that the switch requesting this information is set,
151 -- and that the package does indeed require a body.
153 --------------------------
154 -- Analyze_Package_Body --
155 --------------------------
157 procedure Analyze_Package_Body (N : Node_Id) is
158 Loc : constant Source_Ptr := Sloc (N);
160 begin
161 if Debug_Flag_C then
162 Write_Str ("==> package body ");
163 Write_Name (Chars (Defining_Entity (N)));
164 Write_Str (" from ");
165 Write_Location (Loc);
166 Write_Eol;
167 Indent;
168 end if;
170 -- The real work is split out into the helper, so it can do "return;"
171 -- without skipping the debug output.
173 Analyze_Package_Body_Helper (N);
175 if Debug_Flag_C then
176 Outdent;
177 Write_Str ("<== package body ");
178 Write_Name (Chars (Defining_Entity (N)));
179 Write_Str (" from ");
180 Write_Location (Loc);
181 Write_Eol;
182 end if;
183 end Analyze_Package_Body;
185 -----------------------------------
186 -- Analyze_Package_Body_Contract --
187 -----------------------------------
189 procedure Analyze_Package_Body_Contract (Body_Id : Entity_Id) is
190 Spec_Id : constant Entity_Id := Spec_Entity (Body_Id);
191 Mode : SPARK_Mode_Type;
192 Prag : Node_Id;
194 begin
195 -- Due to the timing of contract analysis, delayed pragmas may be
196 -- subject to the wrong SPARK_Mode, usually that of the enclosing
197 -- context. To remedy this, restore the original SPARK_Mode of the
198 -- related package body.
200 Save_SPARK_Mode_And_Set (Body_Id, Mode);
202 Prag := Get_Pragma (Body_Id, Pragma_Refined_State);
204 -- The analysis of pragma Refined_State detects whether the spec has
205 -- abstract states available for refinement.
207 if Present (Prag) then
208 Analyze_Refined_State_In_Decl_Part (Prag);
210 -- State refinement is required when the package declaration defines at
211 -- least one abstract state. Null states are not considered. Refinement
212 -- is not envorced when SPARK checks are turned off.
214 elsif SPARK_Mode /= Off
215 and then Requires_State_Refinement (Spec_Id, Body_Id)
216 then
217 Error_Msg_N ("package & requires state refinement", Spec_Id);
218 end if;
220 -- Restore the SPARK_Mode of the enclosing context after all delayed
221 -- pragmas have been analyzed.
223 Restore_SPARK_Mode (Mode);
224 end Analyze_Package_Body_Contract;
226 ---------------------------------
227 -- Analyze_Package_Body_Helper --
228 ---------------------------------
230 procedure Analyze_Package_Body_Helper (N : Node_Id) is
231 procedure Hide_Public_Entities (Decls : List_Id);
232 -- Attempt to hide all public entities found in declarative list Decls
233 -- by resetting their Is_Public flag to False depending on whether the
234 -- entities are not referenced by inlined or generic bodies. This kind
235 -- of processing is a conservative approximation and may still leave
236 -- certain entities externally visible.
238 procedure Install_Composite_Operations (P : Entity_Id);
239 -- Composite types declared in the current scope may depend on types
240 -- that were private at the point of declaration, and whose full view
241 -- is now in scope. Indicate that the corresponding operations on the
242 -- composite type are available.
244 --------------------------
245 -- Hide_Public_Entities --
246 --------------------------
248 procedure Hide_Public_Entities (Decls : List_Id) is
249 function Contains_Subp_Or_Const_Refs (N : Node_Id) return Boolean;
250 -- Subsidiary to routine Has_Referencer. Determine whether a node
251 -- contains a reference to a subprogram or a non-static constant.
252 -- WARNING: this is a very expensive routine as it performs a full
253 -- tree traversal.
255 function Has_Referencer
256 (Decls : List_Id;
257 Top_Level : Boolean := False) return Boolean;
258 -- A "referencer" is a construct which may reference a previous
259 -- declaration. Examine all declarations in list Decls in reverse
260 -- and determine whether once such referencer exists. All entities
261 -- in the range Last (Decls) .. Referencer are hidden from external
262 -- visibility.
264 ---------------------------------
265 -- Contains_Subp_Or_Const_Refs --
266 ---------------------------------
268 function Contains_Subp_Or_Const_Refs (N : Node_Id) return Boolean is
269 Reference_Seen : Boolean := False;
271 function Is_Subp_Or_Const_Ref
272 (N : Node_Id) return Traverse_Result;
273 -- Determine whether a node denotes a reference to a subprogram or
274 -- a non-static constant.
276 --------------------------
277 -- Is_Subp_Or_Const_Ref --
278 --------------------------
280 function Is_Subp_Or_Const_Ref
281 (N : Node_Id) return Traverse_Result
283 Val : Node_Id;
285 begin
286 -- Detect a reference of the form
287 -- Subp_Call
289 if Nkind (N) in N_Subprogram_Call
290 and then Is_Entity_Name (Name (N))
291 then
292 Reference_Seen := True;
293 return Abandon;
295 -- Detect a reference of the form
296 -- Subp'Some_Attribute
298 elsif Nkind (N) = N_Attribute_Reference
299 and then Is_Entity_Name (Prefix (N))
300 and then Present (Entity (Prefix (N)))
301 and then Is_Subprogram (Entity (Prefix (N)))
302 then
303 Reference_Seen := True;
304 return Abandon;
306 -- Detect the use of a non-static constant
308 elsif Is_Entity_Name (N)
309 and then Present (Entity (N))
310 and then Ekind (Entity (N)) = E_Constant
311 then
312 Val := Constant_Value (Entity (N));
314 if Present (Val)
315 and then not Compile_Time_Known_Value (Val)
316 then
317 Reference_Seen := True;
318 return Abandon;
319 end if;
320 end if;
322 return OK;
323 end Is_Subp_Or_Const_Ref;
325 procedure Find_Subp_Or_Const_Ref is
326 new Traverse_Proc (Is_Subp_Or_Const_Ref);
328 -- Start of processing for Contains_Subp_Or_Const_Refs
330 begin
331 Find_Subp_Or_Const_Ref (N);
333 return Reference_Seen;
334 end Contains_Subp_Or_Const_Refs;
336 --------------------
337 -- Has_Referencer --
338 --------------------
340 function Has_Referencer
341 (Decls : List_Id;
342 Top_Level : Boolean := False) return Boolean
344 Decl : Node_Id;
345 Decl_Id : Entity_Id;
346 Spec : Node_Id;
348 Has_Non_Subp_Const_Referencer : Boolean := False;
349 -- Flag set for inlined subprogram bodies that do not contain
350 -- references to other subprograms or non-static constants.
352 begin
353 if No (Decls) then
354 return False;
355 end if;
357 -- Examine all declarations in reverse order, hiding all entities
358 -- from external visibility until a referencer has been found. The
359 -- algorithm recurses into nested packages.
361 Decl := Last (Decls);
362 while Present (Decl) loop
364 -- A stub is always considered a referencer
366 if Nkind (Decl) in N_Body_Stub then
367 return True;
369 -- Package declaration
371 elsif Nkind (Decl) = N_Package_Declaration
372 and then not Has_Non_Subp_Const_Referencer
373 then
374 Spec := Specification (Decl);
376 -- Inspect the declarations of a non-generic package to try
377 -- and hide more entities from external visibility.
379 if not Is_Generic_Unit (Defining_Entity (Spec)) then
380 if Has_Referencer (Private_Declarations (Spec))
381 or else Has_Referencer (Visible_Declarations (Spec))
382 then
383 return True;
384 end if;
385 end if;
387 -- Package body
389 elsif Nkind (Decl) = N_Package_Body
390 and then Present (Corresponding_Spec (Decl))
391 then
392 Decl_Id := Corresponding_Spec (Decl);
394 -- A generic package body is a referencer. It would seem
395 -- that we only have to consider generics that can be
396 -- exported, i.e. where the corresponding spec is the
397 -- spec of the current package, but because of nested
398 -- instantiations, a fully private generic body may export
399 -- other private body entities. Furthermore, regardless of
400 -- whether there was a previous inlined subprogram, (an
401 -- instantiation of) the generic package may reference any
402 -- entity declared before it.
404 if Is_Generic_Unit (Decl_Id) then
405 return True;
407 -- Inspect the declarations of a non-generic package body to
408 -- try and hide more entities from external visibility.
410 elsif not Has_Non_Subp_Const_Referencer
411 and then Has_Referencer (Declarations (Decl))
412 then
413 return True;
414 end if;
416 -- Subprogram body
418 elsif Nkind (Decl) = N_Subprogram_Body then
419 if Present (Corresponding_Spec (Decl)) then
420 Decl_Id := Corresponding_Spec (Decl);
422 -- A generic subprogram body acts as a referencer
424 if Is_Generic_Unit (Decl_Id) then
425 return True;
426 end if;
428 -- An inlined subprogram body acts as a referencer
430 if Is_Inlined (Decl_Id)
431 or else Has_Pragma_Inline (Decl_Id)
432 then
433 -- Inspect the statements of the subprogram body
434 -- to determine whether the body references other
435 -- subprograms and/or non-static constants.
437 if Top_Level
438 and then not Contains_Subp_Or_Const_Refs (Decl)
439 then
440 Has_Non_Subp_Const_Referencer := True;
441 else
442 return True;
443 end if;
444 end if;
446 -- Otherwise this is a stand alone subprogram body
448 else
449 Decl_Id := Defining_Entity (Decl);
451 -- An inlined body acts as a referencer. Note that an
452 -- inlined subprogram remains Is_Public as gigi requires
453 -- the flag to be set.
455 -- Note that we test Has_Pragma_Inline here rather than
456 -- Is_Inlined. We are compiling this for a client, and
457 -- it is the client who will decide if actual inlining
458 -- should occur, so we need to assume that the procedure
459 -- could be inlined for the purpose of accessing global
460 -- entities.
462 if Has_Pragma_Inline (Decl_Id) then
463 if Top_Level
464 and then not Contains_Subp_Or_Const_Refs (Decl)
465 then
466 Has_Non_Subp_Const_Referencer := True;
467 else
468 return True;
469 end if;
470 else
471 Set_Is_Public (Decl_Id, False);
472 end if;
473 end if;
475 -- Exceptions, objects and renamings do not need to be public
476 -- if they are not followed by a construct which can reference
477 -- and export them. The Is_Public flag is reset on top level
478 -- entities only as anything nested is local to its context.
480 elsif Nkind_In (Decl, N_Exception_Declaration,
481 N_Object_Declaration,
482 N_Object_Renaming_Declaration,
483 N_Subprogram_Declaration,
484 N_Subprogram_Renaming_Declaration)
485 then
486 Decl_Id := Defining_Entity (Decl);
488 if Top_Level
489 and then not Is_Imported (Decl_Id)
490 and then not Is_Exported (Decl_Id)
491 and then No (Interface_Name (Decl_Id))
492 and then
493 (not Has_Non_Subp_Const_Referencer
494 or else Nkind (Decl) = N_Subprogram_Declaration)
495 then
496 Set_Is_Public (Decl_Id, False);
497 end if;
498 end if;
500 Prev (Decl);
501 end loop;
503 return Has_Non_Subp_Const_Referencer;
504 end Has_Referencer;
506 -- Local variables
508 Discard : Boolean := True;
509 pragma Unreferenced (Discard);
511 -- Start of processing for Hide_Public_Entities
513 begin
514 -- The algorithm examines the top level declarations of a package
515 -- body in reverse looking for a construct that may export entities
516 -- declared prior to it. If such a scenario is encountered, then all
517 -- entities in the range Last (Decls) .. construct are hidden from
518 -- external visibility. Consider:
520 -- package Pack is
521 -- generic
522 -- package Gen is
523 -- end Gen;
524 -- end Pack;
526 -- package body Pack is
527 -- External_Obj : ...; -- (1)
529 -- package body Gen is -- (2)
530 -- ... External_Obj ... -- (3)
531 -- end Gen;
533 -- Local_Obj : ...; -- (4)
534 -- end Pack;
536 -- In this example Local_Obj (4) must not be externally visible as
537 -- it cannot be exported by anything in Pack. The body of generic
538 -- package Gen (2) on the other hand acts as a "referencer" and may
539 -- export anything declared before it. Since the compiler does not
540 -- perform flow analysis, it is not possible to determine precisely
541 -- which entities will be exported when Gen is instantiated. In the
542 -- example above External_Obj (1) is exported at (3), but this may
543 -- not always be the case. The algorithm takes a conservative stance
544 -- and leaves entity External_Obj public.
546 Discard := Has_Referencer (Decls, Top_Level => True);
547 end Hide_Public_Entities;
549 ----------------------------------
550 -- Install_Composite_Operations --
551 ----------------------------------
553 procedure Install_Composite_Operations (P : Entity_Id) is
554 Id : Entity_Id;
556 begin
557 Id := First_Entity (P);
558 while Present (Id) loop
559 if Is_Type (Id)
560 and then (Is_Limited_Composite (Id)
561 or else Is_Private_Composite (Id))
562 and then No (Private_Component (Id))
563 then
564 Set_Is_Limited_Composite (Id, False);
565 Set_Is_Private_Composite (Id, False);
566 end if;
568 Next_Entity (Id);
569 end loop;
570 end Install_Composite_Operations;
572 -- Local variables
574 Body_Id : Entity_Id;
575 HSS : Node_Id;
576 Last_Spec_Entity : Entity_Id;
577 New_N : Node_Id;
578 Pack_Decl : Node_Id;
579 Spec_Id : Entity_Id;
581 -- Start of processing for Analyze_Package_Body_Helper
583 begin
584 -- Find corresponding package specification, and establish the current
585 -- scope. The visible defining entity for the package is the defining
586 -- occurrence in the spec. On exit from the package body, all body
587 -- declarations are attached to the defining entity for the body, but
588 -- the later is never used for name resolution. In this fashion there
589 -- is only one visible entity that denotes the package.
591 -- Set Body_Id. Note that this will be reset to point to the generic
592 -- copy later on in the generic case.
594 Body_Id := Defining_Entity (N);
596 -- Body is body of package instantiation. Corresponding spec has already
597 -- been set.
599 if Present (Corresponding_Spec (N)) then
600 Spec_Id := Corresponding_Spec (N);
601 Pack_Decl := Unit_Declaration_Node (Spec_Id);
603 else
604 Spec_Id := Current_Entity_In_Scope (Defining_Entity (N));
606 if Present (Spec_Id)
607 and then Is_Package_Or_Generic_Package (Spec_Id)
608 then
609 Pack_Decl := Unit_Declaration_Node (Spec_Id);
611 if Nkind (Pack_Decl) = N_Package_Renaming_Declaration then
612 Error_Msg_N ("cannot supply body for package renaming", N);
613 return;
615 elsif Present (Corresponding_Body (Pack_Decl)) then
616 Error_Msg_N ("redefinition of package body", N);
617 return;
618 end if;
620 else
621 Error_Msg_N ("missing specification for package body", N);
622 return;
623 end if;
625 if Is_Package_Or_Generic_Package (Spec_Id)
626 and then (Scope (Spec_Id) = Standard_Standard
627 or else Is_Child_Unit (Spec_Id))
628 and then not Unit_Requires_Body (Spec_Id)
629 then
630 if Ada_Version = Ada_83 then
631 Error_Msg_N
632 ("optional package body (not allowed in Ada 95)??", N);
633 else
634 Error_Msg_N ("spec of this package does not allow a body", N);
635 end if;
636 end if;
637 end if;
639 -- The corresponding spec of the package body may be subject to pragma
640 -- Ghost with policy Ignore. Set the mode now to ensure that any nodes
641 -- generated during analysis and expansion are properly flagged as
642 -- ignored Ghost.
644 Set_Ghost_Mode (N, Spec_Id);
646 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
647 Style.Check_Identifier (Body_Id, Spec_Id);
649 if Is_Child_Unit (Spec_Id) then
650 if Nkind (Parent (N)) /= N_Compilation_Unit then
651 Error_Msg_NE
652 ("body of child unit& cannot be an inner package", N, Spec_Id);
653 end if;
655 Set_Is_Child_Unit (Body_Id);
656 end if;
658 -- Generic package case
660 if Ekind (Spec_Id) = E_Generic_Package then
662 -- Disable expansion and perform semantic analysis on copy. The
663 -- unannotated body will be used in all instantiations.
665 Body_Id := Defining_Entity (N);
666 Set_Ekind (Body_Id, E_Package_Body);
667 Set_Scope (Body_Id, Scope (Spec_Id));
668 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
669 Set_Body_Entity (Spec_Id, Body_Id);
670 Set_Spec_Entity (Body_Id, Spec_Id);
672 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
673 Rewrite (N, New_N);
675 -- Once the contents of the generic copy and the template are
676 -- swapped, do the same for their respective aspect specifications.
678 Exchange_Aspects (N, New_N);
680 -- Update Body_Id to point to the copied node for the remainder of
681 -- the processing.
683 Body_Id := Defining_Entity (N);
684 Start_Generic;
685 end if;
687 -- The Body_Id is that of the copied node in the generic case, the
688 -- current node otherwise. Note that N was rewritten above, so we must
689 -- be sure to get the latest Body_Id value.
691 Set_Ekind (Body_Id, E_Package_Body);
692 Set_Body_Entity (Spec_Id, Body_Id);
693 Set_Spec_Entity (Body_Id, Spec_Id);
695 -- Defining name for the package body is not a visible entity: Only the
696 -- defining name for the declaration is visible.
698 Set_Etype (Body_Id, Standard_Void_Type);
699 Set_Scope (Body_Id, Scope (Spec_Id));
700 Set_Corresponding_Spec (N, Spec_Id);
701 Set_Corresponding_Body (Pack_Decl, Body_Id);
703 -- The body entity is not used for semantics or code generation, but
704 -- it is attached to the entity list of the enclosing scope to simplify
705 -- the listing of back-annotations for the types it main contain.
707 if Scope (Spec_Id) /= Standard_Standard then
708 Append_Entity (Body_Id, Scope (Spec_Id));
709 end if;
711 -- Indicate that we are currently compiling the body of the package
713 Set_In_Package_Body (Spec_Id);
714 Set_Has_Completion (Spec_Id);
715 Last_Spec_Entity := Last_Entity (Spec_Id);
717 if Has_Aspects (N) then
718 Analyze_Aspect_Specifications (N, Body_Id);
719 end if;
721 Push_Scope (Spec_Id);
723 -- Set SPARK_Mode only for non-generic package
725 if Ekind (Spec_Id) = E_Package then
727 -- Set SPARK_Mode from context
729 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
730 Set_SPARK_Pragma_Inherited (Body_Id, True);
732 -- Set elaboration code SPARK mode the same for now
734 Set_SPARK_Aux_Pragma (Body_Id, SPARK_Pragma (Body_Id));
735 Set_SPARK_Aux_Pragma_Inherited (Body_Id, True);
736 end if;
738 -- Inherit the "ghostness" of the subprogram spec. Note that this
739 -- property is not directly inherited as the body may be subject to a
740 -- different Ghost assertion policy.
742 if Is_Ghost_Entity (Spec_Id) or else Ghost_Mode > None then
743 Set_Is_Ghost_Entity (Body_Id);
745 -- The Ghost policy in effect at the point of declaration and at the
746 -- point of completion must match (SPARK RM 6.9(15)).
748 Check_Ghost_Completion (Spec_Id, Body_Id);
749 end if;
751 Set_Categorization_From_Pragmas (N);
753 Install_Visible_Declarations (Spec_Id);
754 Install_Private_Declarations (Spec_Id);
755 Install_Private_With_Clauses (Spec_Id);
756 Install_Composite_Operations (Spec_Id);
758 Check_Anonymous_Access_Types (Spec_Id, N);
760 if Ekind (Spec_Id) = E_Generic_Package then
761 Set_Use (Generic_Formal_Declarations (Pack_Decl));
762 end if;
764 Set_Use (Visible_Declarations (Specification (Pack_Decl)));
765 Set_Use (Private_Declarations (Specification (Pack_Decl)));
767 -- This is a nested package, so it may be necessary to declare certain
768 -- inherited subprograms that are not yet visible because the parent
769 -- type's subprograms are now visible.
771 if Ekind (Scope (Spec_Id)) = E_Package
772 and then Scope (Spec_Id) /= Standard_Standard
773 then
774 Declare_Inherited_Private_Subprograms (Spec_Id);
775 end if;
777 if Present (Declarations (N)) then
778 Analyze_Declarations (Declarations (N));
779 Inspect_Deferred_Constant_Completion (Declarations (N));
780 end if;
782 -- Verify that the SPARK_Mode of the body agrees with that of its spec
784 if Present (SPARK_Pragma (Body_Id)) then
785 if Present (SPARK_Aux_Pragma (Spec_Id)) then
786 if Get_SPARK_Mode_From_Pragma (SPARK_Aux_Pragma (Spec_Id)) = Off
787 and then
788 Get_SPARK_Mode_From_Pragma (SPARK_Pragma (Body_Id)) = On
789 then
790 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
791 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
792 Error_Msg_Sloc := Sloc (SPARK_Aux_Pragma (Spec_Id));
793 Error_Msg_NE
794 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
795 end if;
797 else
798 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
799 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
800 Error_Msg_Sloc := Sloc (Spec_Id);
801 Error_Msg_NE
802 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
803 end if;
804 end if;
806 -- Analyze_Declarations has caused freezing of all types. Now generate
807 -- bodies for RACW primitives and stream attributes, if any.
809 if Ekind (Spec_Id) = E_Package and then Has_RACW (Spec_Id) then
811 -- Attach subprogram bodies to support RACWs declared in spec
813 Append_RACW_Bodies (Declarations (N), Spec_Id);
814 Analyze_List (Declarations (N));
815 end if;
817 HSS := Handled_Statement_Sequence (N);
819 if Present (HSS) then
820 Process_End_Label (HSS, 't', Spec_Id);
821 Analyze (HSS);
823 -- Check that elaboration code in a preelaborable package body is
824 -- empty other than null statements and labels (RM 10.2.1(6)).
826 Validate_Null_Statement_Sequence (N);
827 end if;
829 Validate_Categorization_Dependency (N, Spec_Id);
830 Check_Completion (Body_Id);
832 -- Generate start of body reference. Note that we do this fairly late,
833 -- because the call will use In_Extended_Main_Source_Unit as a check,
834 -- and we want to make sure that Corresponding_Stub links are set
836 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
838 -- For a generic package, collect global references and mark them on
839 -- the original body so that they are not resolved again at the point
840 -- of instantiation.
842 if Ekind (Spec_Id) /= E_Package then
843 Save_Global_References (Original_Node (N));
844 End_Generic;
845 end if;
847 -- The entities of the package body have so far been chained onto the
848 -- declaration chain for the spec. That's been fine while we were in the
849 -- body, since we wanted them to be visible, but now that we are leaving
850 -- the package body, they are no longer visible, so we remove them from
851 -- the entity chain of the package spec entity, and copy them to the
852 -- entity chain of the package body entity, where they will never again
853 -- be visible.
855 if Present (Last_Spec_Entity) then
856 Set_First_Entity (Body_Id, Next_Entity (Last_Spec_Entity));
857 Set_Next_Entity (Last_Spec_Entity, Empty);
858 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
859 Set_Last_Entity (Spec_Id, Last_Spec_Entity);
861 else
862 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
863 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
864 Set_First_Entity (Spec_Id, Empty);
865 Set_Last_Entity (Spec_Id, Empty);
866 end if;
868 End_Package_Scope (Spec_Id);
870 -- All entities declared in body are not visible
872 declare
873 E : Entity_Id;
875 begin
876 E := First_Entity (Body_Id);
877 while Present (E) loop
878 Set_Is_Immediately_Visible (E, False);
879 Set_Is_Potentially_Use_Visible (E, False);
880 Set_Is_Hidden (E);
882 -- Child units may appear on the entity list (e.g. if they appear
883 -- in the context of a subunit) but they are not body entities.
885 if not Is_Child_Unit (E) then
886 Set_Is_Package_Body_Entity (E);
887 end if;
889 Next_Entity (E);
890 end loop;
891 end;
893 Check_References (Body_Id);
895 -- For a generic unit, check that the formal parameters are referenced,
896 -- and that local variables are used, as for regular packages.
898 if Ekind (Spec_Id) = E_Generic_Package then
899 Check_References (Spec_Id);
900 end if;
902 -- At this point all entities of the package body are externally visible
903 -- to the linker as their Is_Public flag is set to True. This proactive
904 -- approach is necessary because an inlined or a generic body for which
905 -- code is generated in other units may need to see these entities. Cut
906 -- down the number of global symbols that do not neet public visibility
907 -- as this has two beneficial effects:
908 -- (1) It makes the compilation process more efficient.
909 -- (2) It gives the code generatormore freedom to optimize within each
910 -- unit, especially subprograms.
912 -- This is done only for top level library packages or child units as
913 -- the algorithm does a top down traversal of the package body.
915 if (Scope (Spec_Id) = Standard_Standard or else Is_Child_Unit (Spec_Id))
916 and then not Is_Generic_Unit (Spec_Id)
917 then
918 Hide_Public_Entities (Declarations (N));
919 end if;
921 -- If expander is not active, then here is where we turn off the
922 -- In_Package_Body flag, otherwise it is turned off at the end of the
923 -- corresponding expansion routine. If this is an instance body, we need
924 -- to qualify names of local entities, because the body may have been
925 -- compiled as a preliminary to another instantiation.
927 if not Expander_Active then
928 Set_In_Package_Body (Spec_Id, False);
930 if Is_Generic_Instance (Spec_Id)
931 and then Operating_Mode = Generate_Code
932 then
933 Qualify_Entity_Names (N);
934 end if;
935 end if;
936 end Analyze_Package_Body_Helper;
938 ------------------------------
939 -- Analyze_Package_Contract --
940 ------------------------------
942 procedure Analyze_Package_Contract (Pack_Id : Entity_Id) is
943 Mode : SPARK_Mode_Type;
944 Prag : Node_Id;
946 begin
947 -- Due to the timing of contract analysis, delayed pragmas may be
948 -- subject to the wrong SPARK_Mode, usually that of the enclosing
949 -- context. To remedy this, restore the original SPARK_Mode of the
950 -- related package.
952 Save_SPARK_Mode_And_Set (Pack_Id, Mode);
954 -- Analyze the initialization related pragmas. Initializes must come
955 -- before Initial_Condition due to item dependencies.
957 Prag := Get_Pragma (Pack_Id, Pragma_Initializes);
959 if Present (Prag) then
960 Analyze_Initializes_In_Decl_Part (Prag);
961 end if;
963 Prag := Get_Pragma (Pack_Id, Pragma_Initial_Condition);
965 if Present (Prag) then
966 Analyze_Initial_Condition_In_Decl_Part (Prag);
967 end if;
969 -- Check whether the lack of indicator Part_Of agrees with the placement
970 -- of the package instantiation with respect to the state space.
972 if Is_Generic_Instance (Pack_Id) then
973 Prag := Get_Pragma (Pack_Id, Pragma_Part_Of);
975 if No (Prag) then
976 Check_Missing_Part_Of (Pack_Id);
977 end if;
978 end if;
980 -- Restore the SPARK_Mode of the enclosing context after all delayed
981 -- pragmas have been analyzed.
983 Restore_SPARK_Mode (Mode);
984 end Analyze_Package_Contract;
986 ---------------------------------
987 -- Analyze_Package_Declaration --
988 ---------------------------------
990 procedure Analyze_Package_Declaration (N : Node_Id) is
991 Id : constant Node_Id := Defining_Entity (N);
993 PF : Boolean;
994 -- True when in the context of a declared pure library unit
996 Body_Required : Boolean;
997 -- True when this package declaration requires a corresponding body
999 Comp_Unit : Boolean;
1000 -- True when this package declaration is not a nested declaration
1002 begin
1003 if Debug_Flag_C then
1004 Write_Str ("==> package spec ");
1005 Write_Name (Chars (Id));
1006 Write_Str (" from ");
1007 Write_Location (Sloc (N));
1008 Write_Eol;
1009 Indent;
1010 end if;
1012 -- The package declaration may be subject to pragma Ghost with policy
1013 -- Ignore. Set the mode now to ensure that any nodes generated during
1014 -- analysis and expansion are properly flagged as ignored Ghost.
1016 Set_Ghost_Mode (N);
1018 Generate_Definition (Id);
1019 Enter_Name (Id);
1020 Set_Ekind (Id, E_Package);
1021 Set_Etype (Id, Standard_Void_Type);
1023 -- Set SPARK_Mode from context only for non-generic package
1025 if Ekind (Id) = E_Package then
1026 Set_SPARK_Pragma (Id, SPARK_Mode_Pragma);
1027 Set_SPARK_Aux_Pragma (Id, SPARK_Mode_Pragma);
1028 Set_SPARK_Pragma_Inherited (Id, True);
1029 Set_SPARK_Aux_Pragma_Inherited (Id, True);
1030 end if;
1032 -- Analyze aspect specifications immediately, since we need to recognize
1033 -- things like Pure early enough to diagnose violations during analysis.
1035 if Has_Aspects (N) then
1036 Analyze_Aspect_Specifications (N, Id);
1037 end if;
1039 -- Ada 2005 (AI-217): Check if the package has been illegally named
1040 -- in a limited-with clause of its own context. In this case the error
1041 -- has been previously notified by Analyze_Context.
1043 -- limited with Pkg; -- ERROR
1044 -- package Pkg is ...
1046 if From_Limited_With (Id) then
1047 return;
1048 end if;
1050 Push_Scope (Id);
1052 PF := Is_Pure (Enclosing_Lib_Unit_Entity);
1053 Set_Is_Pure (Id, PF);
1055 Set_Categorization_From_Pragmas (N);
1057 Analyze (Specification (N));
1058 Validate_Categorization_Dependency (N, Id);
1060 Body_Required := Unit_Requires_Body (Id);
1062 -- When this spec does not require an explicit body, we know that there
1063 -- are no entities requiring completion in the language sense; we call
1064 -- Check_Completion here only to ensure that any nested package
1065 -- declaration that requires an implicit body gets one. (In the case
1066 -- where a body is required, Check_Completion is called at the end of
1067 -- the body's declarative part.)
1069 if not Body_Required then
1070 Check_Completion;
1071 end if;
1073 Comp_Unit := Nkind (Parent (N)) = N_Compilation_Unit;
1074 if Comp_Unit then
1076 -- Set Body_Required indication on the compilation unit node, and
1077 -- determine whether elaboration warnings may be meaningful on it.
1079 Set_Body_Required (Parent (N), Body_Required);
1081 if not Body_Required then
1082 Set_Suppress_Elaboration_Warnings (Id);
1083 end if;
1085 end if;
1087 End_Package_Scope (Id);
1089 -- For the declaration of a library unit that is a remote types package,
1090 -- check legality rules regarding availability of stream attributes for
1091 -- types that contain non-remote access values. This subprogram performs
1092 -- visibility tests that rely on the fact that we have exited the scope
1093 -- of Id.
1095 if Comp_Unit then
1096 Validate_RT_RAT_Component (N);
1097 end if;
1099 if Debug_Flag_C then
1100 Outdent;
1101 Write_Str ("<== package spec ");
1102 Write_Name (Chars (Id));
1103 Write_Str (" from ");
1104 Write_Location (Sloc (N));
1105 Write_Eol;
1106 end if;
1107 end Analyze_Package_Declaration;
1109 -----------------------------------
1110 -- Analyze_Package_Specification --
1111 -----------------------------------
1113 -- Note that this code is shared for the analysis of generic package specs
1114 -- (see Sem_Ch12.Analyze_Generic_Package_Declaration for details).
1116 procedure Analyze_Package_Specification (N : Node_Id) is
1117 Id : constant Entity_Id := Defining_Entity (N);
1118 Orig_Decl : constant Node_Id := Original_Node (Parent (N));
1119 Vis_Decls : constant List_Id := Visible_Declarations (N);
1120 Priv_Decls : constant List_Id := Private_Declarations (N);
1121 E : Entity_Id;
1122 L : Entity_Id;
1123 Public_Child : Boolean;
1125 Private_With_Clauses_Installed : Boolean := False;
1126 -- In Ada 2005, private with_clauses are visible in the private part
1127 -- of a nested package, even if it appears in the public part of the
1128 -- enclosing package. This requires a separate step to install these
1129 -- private_with_clauses, and remove them at the end of the nested
1130 -- package.
1132 procedure Check_One_Tagged_Type_Or_Extension_At_Most;
1133 -- Issue an error in SPARK mode if a package specification contains
1134 -- more than one tagged type or type extension.
1136 procedure Clear_Constants (Id : Entity_Id; FE : Entity_Id);
1137 -- Clears constant indications (Never_Set_In_Source, Constant_Value, and
1138 -- Is_True_Constant) on all variables that are entities of Id, and on
1139 -- the chain whose first element is FE. A recursive call is made for all
1140 -- packages and generic packages.
1142 procedure Generate_Parent_References;
1143 -- For a child unit, generate references to parent units, for
1144 -- GPS navigation purposes.
1146 function Is_Public_Child (Child, Unit : Entity_Id) return Boolean;
1147 -- Child and Unit are entities of compilation units. True if Child
1148 -- is a public child of Parent as defined in 10.1.1
1150 procedure Inspect_Unchecked_Union_Completion (Decls : List_Id);
1151 -- Reject completion of an incomplete or private type declarations
1152 -- having a known discriminant part by an unchecked union.
1154 procedure Install_Parent_Private_Declarations (Inst_Id : Entity_Id);
1155 -- Given the package entity of a generic package instantiation or
1156 -- formal package whose corresponding generic is a child unit, installs
1157 -- the private declarations of each of the child unit's parents.
1158 -- This has to be done at the point of entering the instance package's
1159 -- private part rather than being done in Sem_Ch12.Install_Parent
1160 -- (which is where the parents' visible declarations are installed).
1162 ------------------------------------------------
1163 -- Check_One_Tagged_Type_Or_Extension_At_Most --
1164 ------------------------------------------------
1166 procedure Check_One_Tagged_Type_Or_Extension_At_Most is
1167 Previous : Node_Id;
1169 procedure Check_Decls (Decls : List_Id);
1170 -- Check that either Previous is Empty and Decls does not contain
1171 -- more than one tagged type or type extension, or Previous is
1172 -- already set and Decls contains no tagged type or type extension.
1174 -----------------
1175 -- Check_Decls --
1176 -----------------
1178 procedure Check_Decls (Decls : List_Id) is
1179 Decl : Node_Id;
1181 begin
1182 Decl := First (Decls);
1183 while Present (Decl) loop
1184 if Nkind (Decl) = N_Full_Type_Declaration
1185 and then Is_Tagged_Type (Defining_Identifier (Decl))
1186 then
1187 if No (Previous) then
1188 Previous := Decl;
1190 else
1191 Error_Msg_Sloc := Sloc (Previous);
1192 Check_SPARK_05_Restriction
1193 ("at most one tagged type or type extension allowed",
1194 "\\ previous declaration#",
1195 Decl);
1196 end if;
1197 end if;
1199 Next (Decl);
1200 end loop;
1201 end Check_Decls;
1203 -- Start of processing for Check_One_Tagged_Type_Or_Extension_At_Most
1205 begin
1206 Previous := Empty;
1207 Check_Decls (Vis_Decls);
1209 if Present (Priv_Decls) then
1210 Check_Decls (Priv_Decls);
1211 end if;
1212 end Check_One_Tagged_Type_Or_Extension_At_Most;
1214 ---------------------
1215 -- Clear_Constants --
1216 ---------------------
1218 procedure Clear_Constants (Id : Entity_Id; FE : Entity_Id) is
1219 E : Entity_Id;
1221 begin
1222 -- Ignore package renamings, not interesting and they can cause self
1223 -- referential loops in the code below.
1225 if Nkind (Parent (Id)) = N_Package_Renaming_Declaration then
1226 return;
1227 end if;
1229 -- Note: in the loop below, the check for Next_Entity pointing back
1230 -- to the package entity may seem odd, but it is needed, because a
1231 -- package can contain a renaming declaration to itself, and such
1232 -- renamings are generated automatically within package instances.
1234 E := FE;
1235 while Present (E) and then E /= Id loop
1236 if Is_Assignable (E) then
1237 Set_Never_Set_In_Source (E, False);
1238 Set_Is_True_Constant (E, False);
1239 Set_Current_Value (E, Empty);
1240 Set_Is_Known_Null (E, False);
1241 Set_Last_Assignment (E, Empty);
1243 if not Can_Never_Be_Null (E) then
1244 Set_Is_Known_Non_Null (E, False);
1245 end if;
1247 elsif Is_Package_Or_Generic_Package (E) then
1248 Clear_Constants (E, First_Entity (E));
1249 Clear_Constants (E, First_Private_Entity (E));
1250 end if;
1252 Next_Entity (E);
1253 end loop;
1254 end Clear_Constants;
1256 --------------------------------
1257 -- Generate_Parent_References --
1258 --------------------------------
1260 procedure Generate_Parent_References is
1261 Decl : constant Node_Id := Parent (N);
1263 begin
1264 if Id = Cunit_Entity (Main_Unit)
1265 or else Parent (Decl) = Library_Unit (Cunit (Main_Unit))
1266 then
1267 Generate_Reference (Id, Scope (Id), 'k', False);
1269 elsif not Nkind_In (Unit (Cunit (Main_Unit)), N_Subprogram_Body,
1270 N_Subunit)
1271 then
1272 -- If current unit is an ancestor of main unit, generate a
1273 -- reference to its own parent.
1275 declare
1276 U : Node_Id;
1277 Main_Spec : Node_Id := Unit (Cunit (Main_Unit));
1279 begin
1280 if Nkind (Main_Spec) = N_Package_Body then
1281 Main_Spec := Unit (Library_Unit (Cunit (Main_Unit)));
1282 end if;
1284 U := Parent_Spec (Main_Spec);
1285 while Present (U) loop
1286 if U = Parent (Decl) then
1287 Generate_Reference (Id, Scope (Id), 'k', False);
1288 exit;
1290 elsif Nkind (Unit (U)) = N_Package_Body then
1291 exit;
1293 else
1294 U := Parent_Spec (Unit (U));
1295 end if;
1296 end loop;
1297 end;
1298 end if;
1299 end Generate_Parent_References;
1301 ---------------------
1302 -- Is_Public_Child --
1303 ---------------------
1305 function Is_Public_Child (Child, Unit : Entity_Id) return Boolean is
1306 begin
1307 if not Is_Private_Descendant (Child) then
1308 return True;
1309 else
1310 if Child = Unit then
1311 return not Private_Present (
1312 Parent (Unit_Declaration_Node (Child)));
1313 else
1314 return Is_Public_Child (Scope (Child), Unit);
1315 end if;
1316 end if;
1317 end Is_Public_Child;
1319 ----------------------------------------
1320 -- Inspect_Unchecked_Union_Completion --
1321 ----------------------------------------
1323 procedure Inspect_Unchecked_Union_Completion (Decls : List_Id) is
1324 Decl : Node_Id;
1326 begin
1327 Decl := First (Decls);
1328 while Present (Decl) loop
1330 -- We are looking at an incomplete or private type declaration
1331 -- with a known_discriminant_part whose full view is an
1332 -- Unchecked_Union.
1334 if Nkind_In (Decl, N_Incomplete_Type_Declaration,
1335 N_Private_Type_Declaration)
1336 and then Has_Discriminants (Defining_Identifier (Decl))
1337 and then Present (Full_View (Defining_Identifier (Decl)))
1338 and then
1339 Is_Unchecked_Union (Full_View (Defining_Identifier (Decl)))
1340 then
1341 Error_Msg_N
1342 ("completion of discriminated partial view "
1343 & "cannot be an unchecked union",
1344 Full_View (Defining_Identifier (Decl)));
1345 end if;
1347 Next (Decl);
1348 end loop;
1349 end Inspect_Unchecked_Union_Completion;
1351 -----------------------------------------
1352 -- Install_Parent_Private_Declarations --
1353 -----------------------------------------
1355 procedure Install_Parent_Private_Declarations (Inst_Id : Entity_Id) is
1356 Inst_Par : Entity_Id;
1357 Gen_Par : Entity_Id;
1358 Inst_Node : Node_Id;
1360 begin
1361 Inst_Par := Inst_Id;
1363 Gen_Par :=
1364 Generic_Parent (Specification (Unit_Declaration_Node (Inst_Par)));
1365 while Present (Gen_Par) and then Is_Child_Unit (Gen_Par) loop
1366 Inst_Node := Get_Package_Instantiation_Node (Inst_Par);
1368 if Nkind_In (Inst_Node, N_Package_Instantiation,
1369 N_Formal_Package_Declaration)
1370 and then Nkind (Name (Inst_Node)) = N_Expanded_Name
1371 then
1372 Inst_Par := Entity (Prefix (Name (Inst_Node)));
1374 if Present (Renamed_Entity (Inst_Par)) then
1375 Inst_Par := Renamed_Entity (Inst_Par);
1376 end if;
1378 Gen_Par :=
1379 Generic_Parent
1380 (Specification (Unit_Declaration_Node (Inst_Par)));
1382 -- Install the private declarations and private use clauses
1383 -- of a parent instance of the child instance, unless the
1384 -- parent instance private declarations have already been
1385 -- installed earlier in Analyze_Package_Specification, which
1386 -- happens when a generic child is instantiated, and the
1387 -- instance is a child of the parent instance.
1389 -- Installing the use clauses of the parent instance twice
1390 -- is both unnecessary and wrong, because it would cause the
1391 -- clauses to be chained to themselves in the use clauses
1392 -- list of the scope stack entry. That in turn would cause
1393 -- an endless loop from End_Use_Clauses upon scope exit.
1395 -- The parent is now fully visible. It may be a hidden open
1396 -- scope if we are currently compiling some child instance
1397 -- declared within it, but while the current instance is being
1398 -- compiled the parent is immediately visible. In particular
1399 -- its entities must remain visible if a stack save/restore
1400 -- takes place through a call to Rtsfind.
1402 if Present (Gen_Par) then
1403 if not In_Private_Part (Inst_Par) then
1404 Install_Private_Declarations (Inst_Par);
1405 Set_Use (Private_Declarations
1406 (Specification
1407 (Unit_Declaration_Node (Inst_Par))));
1408 Set_Is_Hidden_Open_Scope (Inst_Par, False);
1409 end if;
1411 -- If we've reached the end of the generic instance parents,
1412 -- then finish off by looping through the nongeneric parents
1413 -- and installing their private declarations.
1415 -- If one of the non-generic parents is itself on the scope
1416 -- stack, do not install its private declarations: they are
1417 -- installed in due time when the private part of that parent
1418 -- is analyzed. This is delicate ???
1420 else
1421 while Present (Inst_Par)
1422 and then Inst_Par /= Standard_Standard
1423 and then (not In_Open_Scopes (Inst_Par)
1424 or else not In_Private_Part (Inst_Par))
1425 loop
1426 Install_Private_Declarations (Inst_Par);
1427 Set_Use (Private_Declarations
1428 (Specification
1429 (Unit_Declaration_Node (Inst_Par))));
1430 Inst_Par := Scope (Inst_Par);
1431 end loop;
1433 exit;
1434 end if;
1436 else
1437 exit;
1438 end if;
1439 end loop;
1440 end Install_Parent_Private_Declarations;
1442 -- Start of processing for Analyze_Package_Specification
1444 begin
1445 if Present (Vis_Decls) then
1446 Analyze_Declarations (Vis_Decls);
1447 end if;
1449 -- Inspect the entities defined in the package and ensure that all
1450 -- incomplete types have received full declarations. Build default
1451 -- initial condition and invariant procedures for all qualifying types.
1453 E := First_Entity (Id);
1454 while Present (E) loop
1456 -- Check on incomplete types
1458 -- AI05-0213: A formal incomplete type has no completion
1460 if Ekind (E) = E_Incomplete_Type
1461 and then No (Full_View (E))
1462 and then not Is_Generic_Type (E)
1463 then
1464 Error_Msg_N ("no declaration in visible part for incomplete}", E);
1465 end if;
1467 if Is_Type (E) then
1469 -- Each private type subject to pragma Default_Initial_Condition
1470 -- declares a specialized procedure which verifies the assumption
1471 -- of the pragma. The declaration appears in the visible part of
1472 -- the package to allow for being called from the outside.
1474 if Has_Default_Init_Cond (E) then
1475 Build_Default_Init_Cond_Procedure_Declaration (E);
1477 -- A private extension inherits the default initial condition
1478 -- procedure from its parent type.
1480 elsif Has_Inherited_Default_Init_Cond (E) then
1481 Inherit_Default_Init_Cond_Procedure (E);
1482 end if;
1484 -- If invariants are present, build the invariant procedure for a
1485 -- private type, but not any of its subtypes or interface types.
1487 if Has_Invariants (E) then
1488 if Ekind (E) = E_Private_Subtype then
1489 null;
1490 else
1491 Build_Invariant_Procedure (E, N);
1492 end if;
1493 end if;
1494 end if;
1496 Next_Entity (E);
1497 end loop;
1499 if Is_Remote_Call_Interface (Id)
1500 and then Nkind (Parent (Parent (N))) = N_Compilation_Unit
1501 then
1502 Validate_RCI_Declarations (Id);
1503 end if;
1505 -- Save global references in the visible declarations, before installing
1506 -- private declarations of parent unit if there is one, because the
1507 -- privacy status of types defined in the parent will change. This is
1508 -- only relevant for generic child units, but is done in all cases for
1509 -- uniformity.
1511 if Ekind (Id) = E_Generic_Package
1512 and then Nkind (Orig_Decl) = N_Generic_Package_Declaration
1513 then
1514 declare
1515 Orig_Spec : constant Node_Id := Specification (Orig_Decl);
1516 Save_Priv : constant List_Id := Private_Declarations (Orig_Spec);
1517 begin
1518 Set_Private_Declarations (Orig_Spec, Empty_List);
1519 Save_Global_References (Orig_Decl);
1520 Set_Private_Declarations (Orig_Spec, Save_Priv);
1521 end;
1522 end if;
1524 -- If package is a public child unit, then make the private declarations
1525 -- of the parent visible.
1527 Public_Child := False;
1529 declare
1530 Par : Entity_Id;
1531 Pack_Decl : Node_Id;
1532 Par_Spec : Node_Id;
1534 begin
1535 Par := Id;
1536 Par_Spec := Parent_Spec (Parent (N));
1538 -- If the package is formal package of an enclosing generic, it is
1539 -- transformed into a local generic declaration, and compiled to make
1540 -- its spec available. We need to retrieve the original generic to
1541 -- determine whether it is a child unit, and install its parents.
1543 if No (Par_Spec)
1544 and then
1545 Nkind (Original_Node (Parent (N))) = N_Formal_Package_Declaration
1546 then
1547 Par := Entity (Name (Original_Node (Parent (N))));
1548 Par_Spec := Parent_Spec (Unit_Declaration_Node (Par));
1549 end if;
1551 if Present (Par_Spec) then
1552 Generate_Parent_References;
1554 while Scope (Par) /= Standard_Standard
1555 and then Is_Public_Child (Id, Par)
1556 and then In_Open_Scopes (Par)
1557 loop
1558 Public_Child := True;
1559 Par := Scope (Par);
1560 Install_Private_Declarations (Par);
1561 Install_Private_With_Clauses (Par);
1562 Pack_Decl := Unit_Declaration_Node (Par);
1563 Set_Use (Private_Declarations (Specification (Pack_Decl)));
1564 end loop;
1565 end if;
1566 end;
1568 if Is_Compilation_Unit (Id) then
1569 Install_Private_With_Clauses (Id);
1570 else
1572 -- The current compilation unit may include private with_clauses,
1573 -- which are visible in the private part of the current nested
1574 -- package, and have to be installed now. This is not done for
1575 -- nested instantiations, where the private with_clauses of the
1576 -- enclosing unit have no effect once the instantiation info is
1577 -- established and we start analyzing the package declaration.
1579 declare
1580 Comp_Unit : constant Entity_Id := Cunit_Entity (Current_Sem_Unit);
1581 begin
1582 if Is_Package_Or_Generic_Package (Comp_Unit)
1583 and then not In_Private_Part (Comp_Unit)
1584 and then not In_Instance
1585 then
1586 Install_Private_With_Clauses (Comp_Unit);
1587 Private_With_Clauses_Installed := True;
1588 end if;
1589 end;
1590 end if;
1592 -- If this is a package associated with a generic instance or formal
1593 -- package, then the private declarations of each of the generic's
1594 -- parents must be installed at this point.
1596 if Is_Generic_Instance (Id) then
1597 Install_Parent_Private_Declarations (Id);
1598 end if;
1600 -- Analyze private part if present. The flag In_Private_Part is reset
1601 -- in End_Package_Scope.
1603 L := Last_Entity (Id);
1605 if Present (Priv_Decls) then
1606 Set_In_Private_Part (Id);
1608 -- Upon entering a public child's private part, it may be necessary
1609 -- to declare subprograms that were derived in the package's visible
1610 -- part but not yet made visible.
1612 if Public_Child then
1613 Declare_Inherited_Private_Subprograms (Id);
1614 end if;
1616 Analyze_Declarations (Priv_Decls);
1618 -- Check the private declarations for incomplete deferred constants
1620 Inspect_Deferred_Constant_Completion (Priv_Decls);
1622 -- The first private entity is the immediate follower of the last
1623 -- visible entity, if there was one.
1625 if Present (L) then
1626 Set_First_Private_Entity (Id, Next_Entity (L));
1627 else
1628 Set_First_Private_Entity (Id, First_Entity (Id));
1629 end if;
1631 -- There may be inherited private subprograms that need to be declared,
1632 -- even in the absence of an explicit private part. If there are any
1633 -- public declarations in the package and the package is a public child
1634 -- unit, then an implicit private part is assumed.
1636 elsif Present (L) and then Public_Child then
1637 Set_In_Private_Part (Id);
1638 Declare_Inherited_Private_Subprograms (Id);
1639 Set_First_Private_Entity (Id, Next_Entity (L));
1640 end if;
1642 E := First_Entity (Id);
1643 while Present (E) loop
1645 -- Check rule of 3.6(11), which in general requires waiting till all
1646 -- full types have been seen.
1648 if Ekind (E) = E_Record_Type or else Ekind (E) = E_Array_Type then
1649 Check_Aliased_Component_Types (E);
1650 end if;
1652 -- Check preelaborable initialization for full type completing a
1653 -- private type for which pragma Preelaborable_Initialization given.
1655 if Is_Type (E)
1656 and then Must_Have_Preelab_Init (E)
1657 and then not Has_Preelaborable_Initialization (E)
1658 then
1659 Error_Msg_N
1660 ("full view of & does not have preelaborable initialization", E);
1661 end if;
1663 -- An invariant may appear on a full view of a type
1665 if Is_Type (E)
1666 and then Has_Private_Declaration (E)
1667 and then Nkind (Parent (E)) = N_Full_Type_Declaration
1668 then
1669 declare
1670 IP_Built : Boolean := False;
1672 begin
1673 if Has_Aspects (Parent (E)) then
1674 declare
1675 ASN : Node_Id;
1677 begin
1678 ASN := First (Aspect_Specifications (Parent (E)));
1679 while Present (ASN) loop
1680 if Nam_In (Chars (Identifier (ASN)),
1681 Name_Invariant,
1682 Name_Type_Invariant)
1683 then
1684 Build_Invariant_Procedure (E, N);
1685 IP_Built := True;
1686 exit;
1687 end if;
1689 Next (ASN);
1690 end loop;
1691 end;
1692 end if;
1694 -- Invariants may have been inherited from progenitors
1696 if not IP_Built
1697 and then Has_Interfaces (E)
1698 and then Has_Inheritable_Invariants (E)
1699 and then not Is_Interface (E)
1700 and then not Is_Class_Wide_Type (E)
1701 then
1702 Build_Invariant_Procedure (E, N);
1703 end if;
1704 end;
1705 end if;
1707 Next_Entity (E);
1708 end loop;
1710 -- Ada 2005 (AI-216): The completion of an incomplete or private type
1711 -- declaration having a known_discriminant_part shall not be an
1712 -- unchecked union type.
1714 if Present (Vis_Decls) then
1715 Inspect_Unchecked_Union_Completion (Vis_Decls);
1716 end if;
1718 if Present (Priv_Decls) then
1719 Inspect_Unchecked_Union_Completion (Priv_Decls);
1720 end if;
1722 if Ekind (Id) = E_Generic_Package
1723 and then Nkind (Orig_Decl) = N_Generic_Package_Declaration
1724 and then Present (Priv_Decls)
1725 then
1726 -- Save global references in private declarations, ignoring the
1727 -- visible declarations that were processed earlier.
1729 declare
1730 Orig_Spec : constant Node_Id := Specification (Orig_Decl);
1731 Save_Vis : constant List_Id := Visible_Declarations (Orig_Spec);
1732 Save_Form : constant List_Id :=
1733 Generic_Formal_Declarations (Orig_Decl);
1735 begin
1736 Set_Visible_Declarations (Orig_Spec, Empty_List);
1737 Set_Generic_Formal_Declarations (Orig_Decl, Empty_List);
1738 Save_Global_References (Orig_Decl);
1739 Set_Generic_Formal_Declarations (Orig_Decl, Save_Form);
1740 Set_Visible_Declarations (Orig_Spec, Save_Vis);
1741 end;
1742 end if;
1744 Process_End_Label (N, 'e', Id);
1746 -- Remove private_with_clauses of enclosing compilation unit, if they
1747 -- were installed.
1749 if Private_With_Clauses_Installed then
1750 Remove_Private_With_Clauses (Cunit (Current_Sem_Unit));
1751 end if;
1753 -- For the case of a library level package, we must go through all the
1754 -- entities clearing the indications that the value may be constant and
1755 -- not modified. Why? Because any client of this package may modify
1756 -- these values freely from anywhere. This also applies to any nested
1757 -- packages or generic packages.
1759 -- For now we unconditionally clear constants for packages that are
1760 -- instances of generic packages. The reason is that we do not have the
1761 -- body yet, and we otherwise think things are unreferenced when they
1762 -- are not. This should be fixed sometime (the effect is not terrible,
1763 -- we just lose some warnings, and also some cases of value propagation)
1764 -- ???
1766 if Is_Library_Level_Entity (Id)
1767 or else Is_Generic_Instance (Id)
1768 then
1769 Clear_Constants (Id, First_Entity (Id));
1770 Clear_Constants (Id, First_Private_Entity (Id));
1771 end if;
1773 -- Issue an error in SPARK mode if a package specification contains
1774 -- more than one tagged type or type extension.
1776 Check_One_Tagged_Type_Or_Extension_At_Most;
1778 -- If switch set, output information on why body required
1780 if List_Body_Required_Info
1781 and then In_Extended_Main_Source_Unit (Id)
1782 and then Unit_Requires_Body (Id)
1783 then
1784 Unit_Requires_Body_Info (Id);
1785 end if;
1786 end Analyze_Package_Specification;
1788 --------------------------------------
1789 -- Analyze_Private_Type_Declaration --
1790 --------------------------------------
1792 procedure Analyze_Private_Type_Declaration (N : Node_Id) is
1793 PF : constant Boolean := Is_Pure (Enclosing_Lib_Unit_Entity);
1794 Id : constant Entity_Id := Defining_Identifier (N);
1796 begin
1797 -- The private type declaration may be subject to pragma Ghost with
1798 -- policy Ignore. Set the mode now to ensure that any nodes generated
1799 -- during analysis and expansion are properly flagged as ignored Ghost.
1801 Set_Ghost_Mode (N);
1803 Generate_Definition (Id);
1804 Set_Is_Pure (Id, PF);
1805 Init_Size_Align (Id);
1807 if not Is_Package_Or_Generic_Package (Current_Scope)
1808 or else In_Private_Part (Current_Scope)
1809 then
1810 Error_Msg_N ("invalid context for private declaration", N);
1811 end if;
1813 New_Private_Type (N, Id, N);
1814 Set_Depends_On_Private (Id);
1816 -- A type declared within a Ghost region is automatically Ghost
1817 -- (SPARK RM 6.9(2)).
1819 if Ghost_Mode > None then
1820 Set_Is_Ghost_Entity (Id);
1821 end if;
1823 if Has_Aspects (N) then
1824 Analyze_Aspect_Specifications (N, Id);
1825 end if;
1826 end Analyze_Private_Type_Declaration;
1828 ----------------------------------
1829 -- Check_Anonymous_Access_Types --
1830 ----------------------------------
1832 procedure Check_Anonymous_Access_Types
1833 (Spec_Id : Entity_Id;
1834 P_Body : Node_Id)
1836 E : Entity_Id;
1837 IR : Node_Id;
1839 begin
1840 -- Itype references are only needed by gigi, to force elaboration of
1841 -- itypes. In the absence of code generation, they are not needed.
1843 if not Expander_Active then
1844 return;
1845 end if;
1847 E := First_Entity (Spec_Id);
1848 while Present (E) loop
1849 if Ekind (E) = E_Anonymous_Access_Type
1850 and then From_Limited_With (E)
1851 then
1852 IR := Make_Itype_Reference (Sloc (P_Body));
1853 Set_Itype (IR, E);
1855 if No (Declarations (P_Body)) then
1856 Set_Declarations (P_Body, New_List (IR));
1857 else
1858 Prepend (IR, Declarations (P_Body));
1859 end if;
1860 end if;
1862 Next_Entity (E);
1863 end loop;
1864 end Check_Anonymous_Access_Types;
1866 -------------------------------------------
1867 -- Declare_Inherited_Private_Subprograms --
1868 -------------------------------------------
1870 procedure Declare_Inherited_Private_Subprograms (Id : Entity_Id) is
1872 function Is_Primitive_Of (T : Entity_Id; S : Entity_Id) return Boolean;
1873 -- Check whether an inherited subprogram S is an operation of an
1874 -- untagged derived type T.
1876 ---------------------
1877 -- Is_Primitive_Of --
1878 ---------------------
1880 function Is_Primitive_Of (T : Entity_Id; S : Entity_Id) return Boolean is
1881 Formal : Entity_Id;
1883 begin
1884 -- If the full view is a scalar type, the type is the anonymous base
1885 -- type, but the operation mentions the first subtype, so check the
1886 -- signature against the base type.
1888 if Base_Type (Etype (S)) = Base_Type (T) then
1889 return True;
1891 else
1892 Formal := First_Formal (S);
1893 while Present (Formal) loop
1894 if Base_Type (Etype (Formal)) = Base_Type (T) then
1895 return True;
1896 end if;
1898 Next_Formal (Formal);
1899 end loop;
1901 return False;
1902 end if;
1903 end Is_Primitive_Of;
1905 -- Local variables
1907 E : Entity_Id;
1908 Op_List : Elist_Id;
1909 Op_Elmt : Elmt_Id;
1910 Op_Elmt_2 : Elmt_Id;
1911 Prim_Op : Entity_Id;
1912 New_Op : Entity_Id := Empty;
1913 Parent_Subp : Entity_Id;
1914 Tag : Entity_Id;
1916 -- Start of processing for Declare_Inherited_Private_Subprograms
1918 begin
1919 E := First_Entity (Id);
1920 while Present (E) loop
1922 -- If the entity is a nonprivate type extension whose parent type
1923 -- is declared in an open scope, then the type may have inherited
1924 -- operations that now need to be made visible. Ditto if the entity
1925 -- is a formal derived type in a child unit.
1927 if ((Is_Derived_Type (E) and then not Is_Private_Type (E))
1928 or else
1929 (Nkind (Parent (E)) = N_Private_Extension_Declaration
1930 and then Is_Generic_Type (E)))
1931 and then In_Open_Scopes (Scope (Etype (E)))
1932 and then Is_Base_Type (E)
1933 then
1934 if Is_Tagged_Type (E) then
1935 Op_List := Primitive_Operations (E);
1936 New_Op := Empty;
1937 Tag := First_Tag_Component (E);
1939 Op_Elmt := First_Elmt (Op_List);
1940 while Present (Op_Elmt) loop
1941 Prim_Op := Node (Op_Elmt);
1943 -- Search primitives that are implicit operations with an
1944 -- internal name whose parent operation has a normal name.
1946 if Present (Alias (Prim_Op))
1947 and then Find_Dispatching_Type (Alias (Prim_Op)) /= E
1948 and then not Comes_From_Source (Prim_Op)
1949 and then Is_Internal_Name (Chars (Prim_Op))
1950 and then not Is_Internal_Name (Chars (Alias (Prim_Op)))
1951 then
1952 Parent_Subp := Alias (Prim_Op);
1954 -- Case 1: Check if the type has also an explicit
1955 -- overriding for this primitive.
1957 Op_Elmt_2 := Next_Elmt (Op_Elmt);
1958 while Present (Op_Elmt_2) loop
1960 -- Skip entities with attribute Interface_Alias since
1961 -- they are not overriding primitives (these entities
1962 -- link an interface primitive with their covering
1963 -- primitive)
1965 if Chars (Node (Op_Elmt_2)) = Chars (Parent_Subp)
1966 and then Type_Conformant (Prim_Op, Node (Op_Elmt_2))
1967 and then No (Interface_Alias (Node (Op_Elmt_2)))
1968 then
1969 -- The private inherited operation has been
1970 -- overridden by an explicit subprogram:
1971 -- replace the former by the latter.
1973 New_Op := Node (Op_Elmt_2);
1974 Replace_Elmt (Op_Elmt, New_Op);
1975 Remove_Elmt (Op_List, Op_Elmt_2);
1976 Set_Overridden_Operation (New_Op, Parent_Subp);
1978 -- We don't need to inherit its dispatching slot.
1979 -- Set_All_DT_Position has previously ensured that
1980 -- the same slot was assigned to the two primitives
1982 if Present (Tag)
1983 and then Present (DTC_Entity (New_Op))
1984 and then Present (DTC_Entity (Prim_Op))
1985 then
1986 pragma Assert
1987 (DT_Position (New_Op) = DT_Position (Prim_Op));
1988 null;
1989 end if;
1991 goto Next_Primitive;
1992 end if;
1994 Next_Elmt (Op_Elmt_2);
1995 end loop;
1997 -- Case 2: We have not found any explicit overriding and
1998 -- hence we need to declare the operation (i.e., make it
1999 -- visible).
2001 Derive_Subprogram (New_Op, Alias (Prim_Op), E, Etype (E));
2003 -- Inherit the dispatching slot if E is already frozen
2005 if Is_Frozen (E)
2006 and then Present (DTC_Entity (Alias (Prim_Op)))
2007 then
2008 Set_DTC_Entity_Value (E, New_Op);
2009 Set_DT_Position_Value (New_Op,
2010 DT_Position (Alias (Prim_Op)));
2011 end if;
2013 pragma Assert
2014 (Is_Dispatching_Operation (New_Op)
2015 and then Node (Last_Elmt (Op_List)) = New_Op);
2017 -- Substitute the new operation for the old one in the
2018 -- type's primitive operations list. Since the new
2019 -- operation was also just added to the end of list,
2020 -- the last element must be removed.
2022 -- (Question: is there a simpler way of declaring the
2023 -- operation, say by just replacing the name of the
2024 -- earlier operation, reentering it in the in the symbol
2025 -- table (how?), and marking it as private???)
2027 Replace_Elmt (Op_Elmt, New_Op);
2028 Remove_Last_Elmt (Op_List);
2029 end if;
2031 <<Next_Primitive>>
2032 Next_Elmt (Op_Elmt);
2033 end loop;
2035 -- Generate listing showing the contents of the dispatch table
2037 if Debug_Flag_ZZ then
2038 Write_DT (E);
2039 end if;
2041 else
2042 -- For untagged type, scan forward to locate inherited hidden
2043 -- operations.
2045 Prim_Op := Next_Entity (E);
2046 while Present (Prim_Op) loop
2047 if Is_Subprogram (Prim_Op)
2048 and then Present (Alias (Prim_Op))
2049 and then not Comes_From_Source (Prim_Op)
2050 and then Is_Internal_Name (Chars (Prim_Op))
2051 and then not Is_Internal_Name (Chars (Alias (Prim_Op)))
2052 and then Is_Primitive_Of (E, Prim_Op)
2053 then
2054 Derive_Subprogram (New_Op, Alias (Prim_Op), E, Etype (E));
2055 end if;
2057 Next_Entity (Prim_Op);
2059 -- Derived operations appear immediately after the type
2060 -- declaration (or the following subtype indication for
2061 -- a derived scalar type). Further declarations cannot
2062 -- include inherited operations of the type.
2064 if Present (Prim_Op) then
2065 exit when Ekind (Prim_Op) not in Overloadable_Kind;
2066 end if;
2067 end loop;
2068 end if;
2069 end if;
2071 Next_Entity (E);
2072 end loop;
2073 end Declare_Inherited_Private_Subprograms;
2075 -----------------------
2076 -- End_Package_Scope --
2077 -----------------------
2079 procedure End_Package_Scope (P : Entity_Id) is
2080 begin
2081 Uninstall_Declarations (P);
2082 Pop_Scope;
2083 end End_Package_Scope;
2085 ---------------------------
2086 -- Exchange_Declarations --
2087 ---------------------------
2089 procedure Exchange_Declarations (Id : Entity_Id) is
2090 Full_Id : constant Entity_Id := Full_View (Id);
2091 H1 : constant Entity_Id := Homonym (Id);
2092 Next1 : constant Entity_Id := Next_Entity (Id);
2093 H2 : Entity_Id;
2094 Next2 : Entity_Id;
2096 begin
2097 -- If missing full declaration for type, nothing to exchange
2099 if No (Full_Id) then
2100 return;
2101 end if;
2103 -- Otherwise complete the exchange, and preserve semantic links
2105 Next2 := Next_Entity (Full_Id);
2106 H2 := Homonym (Full_Id);
2108 -- Reset full declaration pointer to reflect the switched entities and
2109 -- readjust the next entity chains.
2111 Exchange_Entities (Id, Full_Id);
2113 Set_Next_Entity (Id, Next1);
2114 Set_Homonym (Id, H1);
2116 Set_Full_View (Full_Id, Id);
2117 Set_Next_Entity (Full_Id, Next2);
2118 Set_Homonym (Full_Id, H2);
2119 end Exchange_Declarations;
2121 ----------------------------
2122 -- Install_Package_Entity --
2123 ----------------------------
2125 procedure Install_Package_Entity (Id : Entity_Id) is
2126 begin
2127 if not Is_Internal (Id) then
2128 if Debug_Flag_E then
2129 Write_Str ("Install: ");
2130 Write_Name (Chars (Id));
2131 Write_Eol;
2132 end if;
2134 if Is_Child_Unit (Id) then
2135 null;
2137 -- Do not enter implicitly inherited non-overridden subprograms of
2138 -- a tagged type back into visibility if they have non-conformant
2139 -- homographs (Ada RM 8.3 12.3/2).
2141 elsif Is_Hidden_Non_Overridden_Subpgm (Id) then
2142 null;
2144 else
2145 Set_Is_Immediately_Visible (Id);
2146 end if;
2147 end if;
2148 end Install_Package_Entity;
2150 ----------------------------------
2151 -- Install_Private_Declarations --
2152 ----------------------------------
2154 procedure Install_Private_Declarations (P : Entity_Id) is
2155 Id : Entity_Id;
2156 Full : Entity_Id;
2157 Priv_Deps : Elist_Id;
2159 procedure Swap_Private_Dependents (Priv_Deps : Elist_Id);
2160 -- When the full view of a private type is made available, we do the
2161 -- same for its private dependents under proper visibility conditions.
2162 -- When compiling a grand-chid unit this needs to be done recursively.
2164 -----------------------------
2165 -- Swap_Private_Dependents --
2166 -----------------------------
2168 procedure Swap_Private_Dependents (Priv_Deps : Elist_Id) is
2169 Deps : Elist_Id;
2170 Priv : Entity_Id;
2171 Priv_Elmt : Elmt_Id;
2172 Is_Priv : Boolean;
2174 begin
2175 Priv_Elmt := First_Elmt (Priv_Deps);
2176 while Present (Priv_Elmt) loop
2177 Priv := Node (Priv_Elmt);
2179 -- Before the exchange, verify that the presence of the Full_View
2180 -- field. This field will be empty if the entity has already been
2181 -- installed due to a previous call.
2183 if Present (Full_View (Priv)) and then Is_Visible_Dependent (Priv)
2184 then
2185 if Is_Private_Type (Priv) then
2186 Deps := Private_Dependents (Priv);
2187 Is_Priv := True;
2188 else
2189 Is_Priv := False;
2190 end if;
2192 -- For each subtype that is swapped, we also swap the reference
2193 -- to it in Private_Dependents, to allow access to it when we
2194 -- swap them out in End_Package_Scope.
2196 Replace_Elmt (Priv_Elmt, Full_View (Priv));
2197 Exchange_Declarations (Priv);
2198 Set_Is_Immediately_Visible
2199 (Priv, In_Open_Scopes (Scope (Priv)));
2200 Set_Is_Potentially_Use_Visible
2201 (Priv, Is_Potentially_Use_Visible (Node (Priv_Elmt)));
2203 -- Within a child unit, recurse, except in generic child unit,
2204 -- which (unfortunately) handle private_dependents separately.
2206 if Is_Priv
2207 and then Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
2208 and then not Is_Empty_Elmt_List (Deps)
2209 and then not Inside_A_Generic
2210 then
2211 Swap_Private_Dependents (Deps);
2212 end if;
2213 end if;
2215 Next_Elmt (Priv_Elmt);
2216 end loop;
2217 end Swap_Private_Dependents;
2219 -- Start of processing for Install_Private_Declarations
2221 begin
2222 -- First exchange declarations for private types, so that the full
2223 -- declaration is visible. For each private type, we check its
2224 -- Private_Dependents list and also exchange any subtypes of or derived
2225 -- types from it. Finally, if this is a Taft amendment type, the
2226 -- incomplete declaration is irrelevant, and we want to link the
2227 -- eventual full declaration with the original private one so we
2228 -- also skip the exchange.
2230 Id := First_Entity (P);
2231 while Present (Id) and then Id /= First_Private_Entity (P) loop
2232 if Is_Private_Base_Type (Id)
2233 and then Present (Full_View (Id))
2234 and then Comes_From_Source (Full_View (Id))
2235 and then Scope (Full_View (Id)) = Scope (Id)
2236 and then Ekind (Full_View (Id)) /= E_Incomplete_Type
2237 then
2238 -- If there is a use-type clause on the private type, set the full
2239 -- view accordingly.
2241 Set_In_Use (Full_View (Id), In_Use (Id));
2242 Full := Full_View (Id);
2244 if Is_Private_Base_Type (Full)
2245 and then Has_Private_Declaration (Full)
2246 and then Nkind (Parent (Full)) = N_Full_Type_Declaration
2247 and then In_Open_Scopes (Scope (Etype (Full)))
2248 and then In_Package_Body (Current_Scope)
2249 and then not Is_Private_Type (Etype (Full))
2250 then
2251 -- This is the completion of a private type by a derivation
2252 -- from another private type which is not private anymore. This
2253 -- can only happen in a package nested within a child package,
2254 -- when the parent type is defined in the parent unit. At this
2255 -- point the current type is not private either, and we have
2256 -- to install the underlying full view, which is now visible.
2257 -- Save the current full view as well, so that all views can be
2258 -- restored on exit. It may seem that after compiling the child
2259 -- body there are not environments to restore, but the back-end
2260 -- expects those links to be valid, and freeze nodes depend on
2261 -- them.
2263 if No (Full_View (Full))
2264 and then Present (Underlying_Full_View (Full))
2265 then
2266 Set_Full_View (Id, Underlying_Full_View (Full));
2267 Set_Underlying_Full_View (Id, Full);
2269 Set_Underlying_Full_View (Full, Empty);
2270 Set_Is_Frozen (Full_View (Id));
2271 end if;
2272 end if;
2274 Priv_Deps := Private_Dependents (Id);
2275 Exchange_Declarations (Id);
2276 Set_Is_Immediately_Visible (Id);
2277 Swap_Private_Dependents (Priv_Deps);
2278 end if;
2280 Next_Entity (Id);
2281 end loop;
2283 -- Next make other declarations in the private part visible as well
2285 Id := First_Private_Entity (P);
2286 while Present (Id) loop
2287 Install_Package_Entity (Id);
2288 Set_Is_Hidden (Id, False);
2289 Next_Entity (Id);
2290 end loop;
2292 -- Indicate that the private part is currently visible, so it can be
2293 -- properly reset on exit.
2295 Set_In_Private_Part (P);
2296 end Install_Private_Declarations;
2298 ----------------------------------
2299 -- Install_Visible_Declarations --
2300 ----------------------------------
2302 procedure Install_Visible_Declarations (P : Entity_Id) is
2303 Id : Entity_Id;
2304 Last_Entity : Entity_Id;
2306 begin
2307 pragma Assert
2308 (Is_Package_Or_Generic_Package (P) or else Is_Record_Type (P));
2310 if Is_Package_Or_Generic_Package (P) then
2311 Last_Entity := First_Private_Entity (P);
2312 else
2313 Last_Entity := Empty;
2314 end if;
2316 Id := First_Entity (P);
2317 while Present (Id) and then Id /= Last_Entity loop
2318 Install_Package_Entity (Id);
2319 Next_Entity (Id);
2320 end loop;
2321 end Install_Visible_Declarations;
2323 --------------------------
2324 -- Is_Private_Base_Type --
2325 --------------------------
2327 function Is_Private_Base_Type (E : Entity_Id) return Boolean is
2328 begin
2329 return Ekind (E) = E_Private_Type
2330 or else Ekind (E) = E_Limited_Private_Type
2331 or else Ekind (E) = E_Record_Type_With_Private;
2332 end Is_Private_Base_Type;
2334 --------------------------
2335 -- Is_Visible_Dependent --
2336 --------------------------
2338 function Is_Visible_Dependent (Dep : Entity_Id) return Boolean
2340 S : constant Entity_Id := Scope (Dep);
2342 begin
2343 -- Renamings created for actual types have the visibility of the actual
2345 if Ekind (S) = E_Package
2346 and then Is_Generic_Instance (S)
2347 and then (Is_Generic_Actual_Type (Dep)
2348 or else Is_Generic_Actual_Type (Full_View (Dep)))
2349 then
2350 return True;
2352 elsif not (Is_Derived_Type (Dep))
2353 and then Is_Derived_Type (Full_View (Dep))
2354 then
2355 -- When instantiating a package body, the scope stack is empty, so
2356 -- check instead whether the dependent type is defined in the same
2357 -- scope as the instance itself.
2359 return In_Open_Scopes (S)
2360 or else (Is_Generic_Instance (Current_Scope)
2361 and then Scope (Dep) = Scope (Current_Scope));
2362 else
2363 return True;
2364 end if;
2365 end Is_Visible_Dependent;
2367 ----------------------------
2368 -- May_Need_Implicit_Body --
2369 ----------------------------
2371 procedure May_Need_Implicit_Body (E : Entity_Id) is
2372 P : constant Node_Id := Unit_Declaration_Node (E);
2373 S : constant Node_Id := Parent (P);
2374 B : Node_Id;
2375 Decls : List_Id;
2377 begin
2378 if not Has_Completion (E)
2379 and then Nkind (P) = N_Package_Declaration
2380 and then (Present (Activation_Chain_Entity (P)) or else Has_RACW (E))
2381 then
2382 B :=
2383 Make_Package_Body (Sloc (E),
2384 Defining_Unit_Name => Make_Defining_Identifier (Sloc (E),
2385 Chars => Chars (E)),
2386 Declarations => New_List);
2388 if Nkind (S) = N_Package_Specification then
2389 if Present (Private_Declarations (S)) then
2390 Decls := Private_Declarations (S);
2391 else
2392 Decls := Visible_Declarations (S);
2393 end if;
2394 else
2395 Decls := Declarations (S);
2396 end if;
2398 Append (B, Decls);
2399 Analyze (B);
2400 end if;
2401 end May_Need_Implicit_Body;
2403 ----------------------
2404 -- New_Private_Type --
2405 ----------------------
2407 procedure New_Private_Type (N : Node_Id; Id : Entity_Id; Def : Node_Id) is
2408 begin
2409 -- For other than Ada 2012, enter the name in the current scope
2411 if Ada_Version < Ada_2012 then
2412 Enter_Name (Id);
2414 -- Ada 2012 (AI05-0162): Enter the name in the current scope. Note that
2415 -- there may be an incomplete previous view.
2417 else
2418 declare
2419 Prev : Entity_Id;
2420 begin
2421 Prev := Find_Type_Name (N);
2422 pragma Assert (Prev = Id
2423 or else (Ekind (Prev) = E_Incomplete_Type
2424 and then Present (Full_View (Prev))
2425 and then Full_View (Prev) = Id));
2426 end;
2427 end if;
2429 if Limited_Present (Def) then
2430 Set_Ekind (Id, E_Limited_Private_Type);
2431 else
2432 Set_Ekind (Id, E_Private_Type);
2433 end if;
2435 Set_Etype (Id, Id);
2436 Set_Has_Delayed_Freeze (Id);
2437 Set_Is_First_Subtype (Id);
2438 Init_Size_Align (Id);
2440 Set_Is_Constrained (Id,
2441 No (Discriminant_Specifications (N))
2442 and then not Unknown_Discriminants_Present (N));
2444 -- Set tagged flag before processing discriminants, to catch illegal
2445 -- usage.
2447 Set_Is_Tagged_Type (Id, Tagged_Present (Def));
2449 Set_Discriminant_Constraint (Id, No_Elist);
2450 Set_Stored_Constraint (Id, No_Elist);
2452 if Present (Discriminant_Specifications (N)) then
2453 Push_Scope (Id);
2454 Process_Discriminants (N);
2455 End_Scope;
2457 elsif Unknown_Discriminants_Present (N) then
2458 Set_Has_Unknown_Discriminants (Id);
2459 end if;
2461 Set_Private_Dependents (Id, New_Elmt_List);
2463 if Tagged_Present (Def) then
2464 Set_Ekind (Id, E_Record_Type_With_Private);
2465 Set_Direct_Primitive_Operations (Id, New_Elmt_List);
2466 Set_Is_Abstract_Type (Id, Abstract_Present (Def));
2467 Set_Is_Limited_Record (Id, Limited_Present (Def));
2468 Set_Has_Delayed_Freeze (Id, True);
2470 -- Create a class-wide type with the same attributes
2472 Make_Class_Wide_Type (Id);
2474 elsif Abstract_Present (Def) then
2475 Error_Msg_N ("only a tagged type can be abstract", N);
2476 end if;
2477 end New_Private_Type;
2479 ---------------------------------
2480 -- Requires_Completion_In_Body --
2481 ---------------------------------
2483 function Requires_Completion_In_Body
2484 (Id : Entity_Id;
2485 Pack_Id : Entity_Id) return Boolean
2487 begin
2488 -- Always ignore child units. Child units get added to the entity list
2489 -- of a parent unit, but are not original entities of the parent, and
2490 -- so do not affect whether the parent needs a body.
2492 if Is_Child_Unit (Id) then
2493 return False;
2495 -- Ignore formal packages and their renamings
2497 elsif Ekind (Id) = E_Package
2498 and then Nkind (Original_Node (Unit_Declaration_Node (Id))) =
2499 N_Formal_Package_Declaration
2500 then
2501 return False;
2503 -- A Ghost entity declared in a non-Ghost package does not force the
2504 -- need for a body (SPARK RM 6.9(11)).
2506 elsif not Is_Ghost_Entity (Pack_Id) and then Is_Ghost_Entity (Id) then
2507 return False;
2509 -- Otherwise test to see if entity requires a completion. Note that
2510 -- subprogram entities whose declaration does not come from source are
2511 -- ignored here on the basis that we assume the expander will provide an
2512 -- implicit completion at some point.
2514 elsif (Is_Overloadable (Id)
2515 and then Ekind (Id) /= E_Enumeration_Literal
2516 and then Ekind (Id) /= E_Operator
2517 and then not Is_Abstract_Subprogram (Id)
2518 and then not Has_Completion (Id)
2519 and then Comes_From_Source (Parent (Id)))
2521 or else
2522 (Ekind (Id) = E_Package
2523 and then Id /= Pack_Id
2524 and then not Has_Completion (Id)
2525 and then Unit_Requires_Body (Id))
2527 or else
2528 (Ekind (Id) = E_Incomplete_Type
2529 and then No (Full_View (Id))
2530 and then not Is_Generic_Type (Id))
2532 or else
2533 (Ekind_In (Id, E_Task_Type, E_Protected_Type)
2534 and then not Has_Completion (Id))
2536 or else
2537 (Ekind (Id) = E_Generic_Package
2538 and then Id /= Pack_Id
2539 and then not Has_Completion (Id)
2540 and then Unit_Requires_Body (Id))
2542 or else
2543 (Is_Generic_Subprogram (Id)
2544 and then not Has_Completion (Id))
2546 then
2547 return True;
2549 -- Otherwise the entity does not require completion in a package body
2551 else
2552 return False;
2553 end if;
2554 end Requires_Completion_In_Body;
2556 ----------------------------
2557 -- Uninstall_Declarations --
2558 ----------------------------
2560 procedure Uninstall_Declarations (P : Entity_Id) is
2561 Decl : constant Node_Id := Unit_Declaration_Node (P);
2562 Id : Entity_Id;
2563 Full : Entity_Id;
2564 Priv_Elmt : Elmt_Id;
2565 Priv_Sub : Entity_Id;
2567 procedure Preserve_Full_Attributes (Priv, Full : Entity_Id);
2568 -- Copy to the private declaration the attributes of the full view that
2569 -- need to be available for the partial view also.
2571 function Type_In_Use (T : Entity_Id) return Boolean;
2572 -- Check whether type or base type appear in an active use_type clause
2574 ------------------------------
2575 -- Preserve_Full_Attributes --
2576 ------------------------------
2578 procedure Preserve_Full_Attributes (Priv, Full : Entity_Id) is
2579 Priv_Is_Base_Type : constant Boolean := Is_Base_Type (Priv);
2581 begin
2582 Set_Size_Info (Priv, (Full));
2583 Set_RM_Size (Priv, RM_Size (Full));
2584 Set_Size_Known_At_Compile_Time
2585 (Priv, Size_Known_At_Compile_Time (Full));
2586 Set_Is_Volatile (Priv, Is_Volatile (Full));
2587 Set_Treat_As_Volatile (Priv, Treat_As_Volatile (Full));
2588 Set_Is_Ada_2005_Only (Priv, Is_Ada_2005_Only (Full));
2589 Set_Is_Ada_2012_Only (Priv, Is_Ada_2012_Only (Full));
2590 Set_Has_Pragma_Unmodified (Priv, Has_Pragma_Unmodified (Full));
2591 Set_Has_Pragma_Unreferenced (Priv, Has_Pragma_Unreferenced (Full));
2592 Set_Has_Pragma_Unreferenced_Objects
2593 (Priv, Has_Pragma_Unreferenced_Objects
2594 (Full));
2595 if Is_Unchecked_Union (Full) then
2596 Set_Is_Unchecked_Union (Base_Type (Priv));
2597 end if;
2598 -- Why is atomic not copied here ???
2600 if Referenced (Full) then
2601 Set_Referenced (Priv);
2602 end if;
2604 if Priv_Is_Base_Type then
2605 Set_Is_Controlled (Priv, Is_Controlled (Base_Type (Full)));
2606 Set_Finalize_Storage_Only
2607 (Priv, Finalize_Storage_Only
2608 (Base_Type (Full)));
2609 Set_Has_Task (Priv, Has_Task (Base_Type (Full)));
2610 Set_Has_Protected (Priv, Has_Protected (Base_Type (Full)));
2611 Set_Has_Controlled_Component
2612 (Priv, Has_Controlled_Component
2613 (Base_Type (Full)));
2614 end if;
2616 Set_Freeze_Node (Priv, Freeze_Node (Full));
2618 -- Propagate information of type invariants, which may be specified
2619 -- for the full view.
2621 if Has_Invariants (Full) and not Has_Invariants (Priv) then
2622 Set_Has_Invariants (Priv);
2623 Set_Subprograms_For_Type (Priv, Subprograms_For_Type (Full));
2624 end if;
2626 if Is_Tagged_Type (Priv)
2627 and then Is_Tagged_Type (Full)
2628 and then not Error_Posted (Full)
2629 then
2630 if Is_Tagged_Type (Priv) then
2632 -- If the type is tagged, the tag itself must be available on
2633 -- the partial view, for expansion purposes.
2635 Set_First_Entity (Priv, First_Entity (Full));
2637 -- If there are discriminants in the partial view, these remain
2638 -- visible. Otherwise only the tag itself is visible, and there
2639 -- are no nameable components in the partial view.
2641 if No (Last_Entity (Priv)) then
2642 Set_Last_Entity (Priv, First_Entity (Priv));
2643 end if;
2644 end if;
2646 Set_Has_Discriminants (Priv, Has_Discriminants (Full));
2648 if Has_Discriminants (Full) then
2649 Set_Discriminant_Constraint (Priv,
2650 Discriminant_Constraint (Full));
2651 end if;
2652 end if;
2653 end Preserve_Full_Attributes;
2655 -----------------
2656 -- Type_In_Use --
2657 -----------------
2659 function Type_In_Use (T : Entity_Id) return Boolean is
2660 begin
2661 return Scope (Base_Type (T)) = P
2662 and then (In_Use (T) or else In_Use (Base_Type (T)));
2663 end Type_In_Use;
2665 -- Start of processing for Uninstall_Declarations
2667 begin
2668 Id := First_Entity (P);
2669 while Present (Id) and then Id /= First_Private_Entity (P) loop
2670 if Debug_Flag_E then
2671 Write_Str ("unlinking visible entity ");
2672 Write_Int (Int (Id));
2673 Write_Eol;
2674 end if;
2676 -- On exit from the package scope, we must preserve the visibility
2677 -- established by use clauses in the current scope. Two cases:
2679 -- a) If the entity is an operator, it may be a primitive operator of
2680 -- a type for which there is a visible use-type clause.
2682 -- b) for other entities, their use-visibility is determined by a
2683 -- visible use clause for the package itself. For a generic instance,
2684 -- the instantiation of the formals appears in the visible part,
2685 -- but the formals are private and remain so.
2687 if Ekind (Id) = E_Function
2688 and then Is_Operator_Symbol_Name (Chars (Id))
2689 and then not Is_Hidden (Id)
2690 and then not Error_Posted (Id)
2691 then
2692 Set_Is_Potentially_Use_Visible (Id,
2693 In_Use (P)
2694 or else Type_In_Use (Etype (Id))
2695 or else Type_In_Use (Etype (First_Formal (Id)))
2696 or else (Present (Next_Formal (First_Formal (Id)))
2697 and then
2698 Type_In_Use
2699 (Etype (Next_Formal (First_Formal (Id))))));
2700 else
2701 if In_Use (P) and then not Is_Hidden (Id) then
2703 -- A child unit of a use-visible package remains use-visible
2704 -- only if it is itself a visible child unit. Otherwise it
2705 -- would remain visible in other contexts where P is use-
2706 -- visible, because once compiled it stays in the entity list
2707 -- of its parent unit.
2709 if Is_Child_Unit (Id) then
2710 Set_Is_Potentially_Use_Visible
2711 (Id, Is_Visible_Lib_Unit (Id));
2712 else
2713 Set_Is_Potentially_Use_Visible (Id);
2714 end if;
2716 else
2717 Set_Is_Potentially_Use_Visible (Id, False);
2718 end if;
2719 end if;
2721 -- Local entities are not immediately visible outside of the package
2723 Set_Is_Immediately_Visible (Id, False);
2725 -- If this is a private type with a full view (for example a local
2726 -- subtype of a private type declared elsewhere), ensure that the
2727 -- full view is also removed from visibility: it may be exposed when
2728 -- swapping views in an instantiation.
2730 if Is_Type (Id) and then Present (Full_View (Id)) then
2731 Set_Is_Immediately_Visible (Full_View (Id), False);
2732 end if;
2734 if Is_Tagged_Type (Id) and then Ekind (Id) = E_Record_Type then
2735 Check_Abstract_Overriding (Id);
2736 Check_Conventions (Id);
2737 end if;
2739 if Ekind_In (Id, E_Private_Type, E_Limited_Private_Type)
2740 and then No (Full_View (Id))
2741 and then not Is_Generic_Type (Id)
2742 and then not Is_Derived_Type (Id)
2743 then
2744 Error_Msg_N ("missing full declaration for private type&", Id);
2746 elsif Ekind (Id) = E_Record_Type_With_Private
2747 and then not Is_Generic_Type (Id)
2748 and then No (Full_View (Id))
2749 then
2750 if Nkind (Parent (Id)) = N_Private_Type_Declaration then
2751 Error_Msg_N ("missing full declaration for private type&", Id);
2752 else
2753 Error_Msg_N
2754 ("missing full declaration for private extension", Id);
2755 end if;
2757 -- Case of constant, check for deferred constant declaration with
2758 -- no full view. Likely just a matter of a missing expression, or
2759 -- accidental use of the keyword constant.
2761 elsif Ekind (Id) = E_Constant
2763 -- OK if constant value present
2765 and then No (Constant_Value (Id))
2767 -- OK if full view present
2769 and then No (Full_View (Id))
2771 -- OK if imported, since that provides the completion
2773 and then not Is_Imported (Id)
2775 -- OK if object declaration replaced by renaming declaration as
2776 -- a result of OK_To_Rename processing (e.g. for concatenation)
2778 and then Nkind (Parent (Id)) /= N_Object_Renaming_Declaration
2780 -- OK if object declaration with the No_Initialization flag set
2782 and then not (Nkind (Parent (Id)) = N_Object_Declaration
2783 and then No_Initialization (Parent (Id)))
2784 then
2785 -- If no private declaration is present, we assume the user did
2786 -- not intend a deferred constant declaration and the problem
2787 -- is simply that the initializing expression is missing.
2789 if not Has_Private_Declaration (Etype (Id)) then
2791 -- We assume that the user did not intend a deferred constant
2792 -- declaration, and the expression is just missing.
2794 Error_Msg_N
2795 ("constant declaration requires initialization expression",
2796 Parent (Id));
2798 if Is_Limited_Type (Etype (Id)) then
2799 Error_Msg_N
2800 ("\if variable intended, remove CONSTANT from declaration",
2801 Parent (Id));
2802 end if;
2804 -- Otherwise if a private declaration is present, then we are
2805 -- missing the full declaration for the deferred constant.
2807 else
2808 Error_Msg_N
2809 ("missing full declaration for deferred constant (RM 7.4)",
2810 Id);
2812 if Is_Limited_Type (Etype (Id)) then
2813 Error_Msg_N
2814 ("\if variable intended, remove CONSTANT from declaration",
2815 Parent (Id));
2816 end if;
2817 end if;
2818 end if;
2820 Next_Entity (Id);
2821 end loop;
2823 -- If the specification was installed as the parent of a public child
2824 -- unit, the private declarations were not installed, and there is
2825 -- nothing to do.
2827 if not In_Private_Part (P) then
2828 return;
2829 else
2830 Set_In_Private_Part (P, False);
2831 end if;
2833 -- Make private entities invisible and exchange full and private
2834 -- declarations for private types. Id is now the first private entity
2835 -- in the package.
2837 while Present (Id) loop
2838 if Debug_Flag_E then
2839 Write_Str ("unlinking private entity ");
2840 Write_Int (Int (Id));
2841 Write_Eol;
2842 end if;
2844 if Is_Tagged_Type (Id) and then Ekind (Id) = E_Record_Type then
2845 Check_Abstract_Overriding (Id);
2846 Check_Conventions (Id);
2847 end if;
2849 Set_Is_Immediately_Visible (Id, False);
2851 if Is_Private_Base_Type (Id) and then Present (Full_View (Id)) then
2852 Full := Full_View (Id);
2854 -- If the partial view is not declared in the visible part of the
2855 -- package (as is the case when it is a type derived from some
2856 -- other private type in the private part of the current package),
2857 -- no exchange takes place.
2859 if No (Parent (Id))
2860 or else List_Containing (Parent (Id)) /=
2861 Visible_Declarations (Specification (Decl))
2862 then
2863 goto Next_Id;
2864 end if;
2866 -- The entry in the private part points to the full declaration,
2867 -- which is currently visible. Exchange them so only the private
2868 -- type declaration remains accessible, and link private and full
2869 -- declaration in the opposite direction. Before the actual
2870 -- exchange, we copy back attributes of the full view that must
2871 -- be available to the partial view too.
2873 Preserve_Full_Attributes (Id, Full);
2875 Set_Is_Potentially_Use_Visible (Id, In_Use (P));
2877 -- The following test may be redundant, as this is already
2878 -- diagnosed in sem_ch3. ???
2880 if Is_Indefinite_Subtype (Full)
2881 and then not Is_Indefinite_Subtype (Id)
2882 then
2883 Error_Msg_Sloc := Sloc (Parent (Id));
2884 Error_Msg_NE
2885 ("full view of& not compatible with declaration#", Full, Id);
2886 end if;
2888 -- Swap out the subtypes and derived types of Id that
2889 -- were compiled in this scope, or installed previously
2890 -- by Install_Private_Declarations.
2892 -- Before we do the swap, we verify the presence of the Full_View
2893 -- field which may be empty due to a swap by a previous call to
2894 -- End_Package_Scope (e.g. from the freezing mechanism).
2896 Priv_Elmt := First_Elmt (Private_Dependents (Id));
2897 while Present (Priv_Elmt) loop
2898 Priv_Sub := Node (Priv_Elmt);
2900 if Present (Full_View (Priv_Sub)) then
2901 if Scope (Priv_Sub) = P
2902 or else not In_Open_Scopes (Scope (Priv_Sub))
2903 then
2904 Set_Is_Immediately_Visible (Priv_Sub, False);
2905 end if;
2907 if Is_Visible_Dependent (Priv_Sub) then
2908 Preserve_Full_Attributes
2909 (Priv_Sub, Full_View (Priv_Sub));
2910 Replace_Elmt (Priv_Elmt, Full_View (Priv_Sub));
2911 Exchange_Declarations (Priv_Sub);
2912 end if;
2913 end if;
2915 Next_Elmt (Priv_Elmt);
2916 end loop;
2918 -- Now restore the type itself to its private view
2920 Exchange_Declarations (Id);
2922 -- If we have installed an underlying full view for a type derived
2923 -- from a private type in a child unit, restore the proper views
2924 -- of private and full view. See corresponding code in
2925 -- Install_Private_Declarations.
2927 -- After the exchange, Full denotes the private type in the
2928 -- visible part of the package.
2930 if Is_Private_Base_Type (Full)
2931 and then Present (Full_View (Full))
2932 and then Present (Underlying_Full_View (Full))
2933 and then In_Package_Body (Current_Scope)
2934 then
2935 Set_Full_View (Full, Underlying_Full_View (Full));
2936 Set_Underlying_Full_View (Full, Empty);
2937 end if;
2939 elsif Ekind (Id) = E_Incomplete_Type
2940 and then Comes_From_Source (Id)
2941 and then No (Full_View (Id))
2942 then
2943 -- Mark Taft amendment types. Verify that there are no primitive
2944 -- operations declared for the type (3.10.1(9)).
2946 Set_Has_Completion_In_Body (Id);
2948 declare
2949 Elmt : Elmt_Id;
2950 Subp : Entity_Id;
2952 begin
2953 Elmt := First_Elmt (Private_Dependents (Id));
2954 while Present (Elmt) loop
2955 Subp := Node (Elmt);
2957 -- Is_Primitive is tested because there can be cases where
2958 -- nonprimitive subprograms (in nested packages) are added
2959 -- to the Private_Dependents list.
2961 if Is_Overloadable (Subp) and then Is_Primitive (Subp) then
2962 Error_Msg_NE
2963 ("type& must be completed in the private part",
2964 Parent (Subp), Id);
2966 -- The result type of an access-to-function type cannot be a
2967 -- Taft-amendment type, unless the version is Ada 2012 or
2968 -- later (see AI05-151).
2970 elsif Ada_Version < Ada_2012
2971 and then Ekind (Subp) = E_Subprogram_Type
2972 then
2973 if Etype (Subp) = Id
2974 or else
2975 (Is_Class_Wide_Type (Etype (Subp))
2976 and then Etype (Etype (Subp)) = Id)
2977 then
2978 Error_Msg_NE
2979 ("type& must be completed in the private part",
2980 Associated_Node_For_Itype (Subp), Id);
2981 end if;
2982 end if;
2984 Next_Elmt (Elmt);
2985 end loop;
2986 end;
2988 elsif not Is_Child_Unit (Id)
2989 and then (not Is_Private_Type (Id) or else No (Full_View (Id)))
2990 then
2991 Set_Is_Hidden (Id);
2992 Set_Is_Potentially_Use_Visible (Id, False);
2993 end if;
2995 <<Next_Id>>
2996 Next_Entity (Id);
2997 end loop;
2998 end Uninstall_Declarations;
3000 ------------------------
3001 -- Unit_Requires_Body --
3002 ------------------------
3004 function Unit_Requires_Body
3005 (Pack_Id : Entity_Id;
3006 Ignore_Abstract_State : Boolean := False) return Boolean
3008 E : Entity_Id;
3010 begin
3011 -- Imported entity never requires body. Right now, only subprograms can
3012 -- be imported, but perhaps in the future we will allow import of
3013 -- packages.
3015 if Is_Imported (Pack_Id) then
3016 return False;
3018 -- Body required if library package with pragma Elaborate_Body
3020 elsif Has_Pragma_Elaborate_Body (Pack_Id) then
3021 return True;
3023 -- Body required if subprogram
3025 elsif Is_Subprogram_Or_Generic_Subprogram (Pack_Id) then
3026 return True;
3028 -- Treat a block as requiring a body
3030 elsif Ekind (Pack_Id) = E_Block then
3031 return True;
3033 elsif Ekind (Pack_Id) = E_Package
3034 and then Nkind (Parent (Pack_Id)) = N_Package_Specification
3035 and then Present (Generic_Parent (Parent (Pack_Id)))
3036 then
3037 declare
3038 G_P : constant Entity_Id := Generic_Parent (Parent (Pack_Id));
3039 begin
3040 if Has_Pragma_Elaborate_Body (G_P) then
3041 return True;
3042 end if;
3043 end;
3045 -- A [generic] package that introduces at least one non-null abstract
3046 -- state requires completion. However, there is a separate rule that
3047 -- requires that such a package have a reason other than this for a
3048 -- body being required (if necessary a pragma Elaborate_Body must be
3049 -- provided). If Ignore_Abstract_State is True, we don't do this check
3050 -- (so we can use Unit_Requires_Body to check for some other reason).
3052 elsif Ekind_In (Pack_Id, E_Generic_Package, E_Package)
3053 and then not Ignore_Abstract_State
3054 and then Present (Abstract_States (Pack_Id))
3055 and then not Is_Null_State
3056 (Node (First_Elmt (Abstract_States (Pack_Id))))
3057 then
3058 return True;
3059 end if;
3061 -- Otherwise search entity chain for entity requiring completion
3063 E := First_Entity (Pack_Id);
3064 while Present (E) loop
3065 if Requires_Completion_In_Body (E, Pack_Id) then
3066 return True;
3067 end if;
3069 Next_Entity (E);
3070 end loop;
3072 return False;
3073 end Unit_Requires_Body;
3075 -----------------------------
3076 -- Unit_Requires_Body_Info --
3077 -----------------------------
3079 procedure Unit_Requires_Body_Info (Pack_Id : Entity_Id) is
3080 E : Entity_Id;
3082 begin
3083 -- An imported entity never requires body. Right now, only subprograms
3084 -- can be imported, but perhaps in the future we will allow import of
3085 -- packages.
3087 if Is_Imported (Pack_Id) then
3088 return;
3090 -- Body required if library package with pragma Elaborate_Body
3092 elsif Has_Pragma_Elaborate_Body (Pack_Id) then
3093 Error_Msg_N ("info: & requires body (Elaborate_Body)?Y?", Pack_Id);
3095 -- Body required if subprogram
3097 elsif Is_Subprogram_Or_Generic_Subprogram (Pack_Id) then
3098 Error_Msg_N ("info: & requires body (subprogram case)?Y?", Pack_Id);
3100 -- Body required if generic parent has Elaborate_Body
3102 elsif Ekind (Pack_Id) = E_Package
3103 and then Nkind (Parent (Pack_Id)) = N_Package_Specification
3104 and then Present (Generic_Parent (Parent (Pack_Id)))
3105 then
3106 declare
3107 G_P : constant Entity_Id := Generic_Parent (Parent (Pack_Id));
3108 begin
3109 if Has_Pragma_Elaborate_Body (G_P) then
3110 Error_Msg_N
3111 ("info: & requires body (generic parent Elaborate_Body)?Y?",
3112 Pack_Id);
3113 end if;
3114 end;
3116 -- A [generic] package that introduces at least one non-null abstract
3117 -- state requires completion. However, there is a separate rule that
3118 -- requires that such a package have a reason other than this for a
3119 -- body being required (if necessary a pragma Elaborate_Body must be
3120 -- provided). If Ignore_Abstract_State is True, we don't do this check
3121 -- (so we can use Unit_Requires_Body to check for some other reason).
3123 elsif Ekind_In (Pack_Id, E_Generic_Package, E_Package)
3124 and then Present (Abstract_States (Pack_Id))
3125 and then not Is_Null_State
3126 (Node (First_Elmt (Abstract_States (Pack_Id))))
3127 then
3128 Error_Msg_N
3129 ("info: & requires body (non-null abstract state aspect)?Y?",
3130 Pack_Id);
3131 end if;
3133 -- Otherwise search entity chain for entity requiring completion
3135 E := First_Entity (Pack_Id);
3136 while Present (E) loop
3137 if Requires_Completion_In_Body (E, Pack_Id) then
3138 Error_Msg_Node_2 := E;
3139 Error_Msg_NE
3140 ("info: & requires body (& requires completion)?Y?", E, Pack_Id);
3141 end if;
3143 Next_Entity (E);
3144 end loop;
3145 end Unit_Requires_Body_Info;
3146 end Sem_Ch7;